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Diffstat (limited to 'src/xdp/include/linux/bpf.h')
| -rw-r--r-- | src/xdp/include/linux/bpf.h | 3278 |
1 files changed, 0 insertions, 3278 deletions
diff --git a/src/xdp/include/linux/bpf.h b/src/xdp/include/linux/bpf.h deleted file mode 100644 index 161a93809..000000000 --- a/src/xdp/include/linux/bpf.h +++ /dev/null @@ -1,3278 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ -/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General Public - * License as published by the Free Software Foundation. - */ -#ifndef _UAPI__LINUX_BPF_H__ -#define _UAPI__LINUX_BPF_H__ - -#include <linux/types.h> -#include <linux/bpf_common.h> - -/* Extended instruction set based on top of classic BPF */ - -/* instruction classes */ -#define BPF_JMP32 0x06 /* jmp mode in word width */ -#define BPF_ALU64 0x07 /* alu mode in double word width */ - -/* ld/ldx fields */ -#define BPF_DW 0x18 /* double word (64-bit) */ -#define BPF_XADD 0xc0 /* exclusive add */ - -/* alu/jmp fields */ -#define BPF_MOV 0xb0 /* mov reg to reg */ -#define BPF_ARSH 0xc0 /* sign extending arithmetic shift right */ - -/* change endianness of a register */ -#define BPF_END 0xd0 /* flags for endianness conversion: */ -#define BPF_TO_LE 0x00 /* convert to little-endian */ -#define BPF_TO_BE 0x08 /* convert to big-endian */ -#define BPF_FROM_LE BPF_TO_LE -#define BPF_FROM_BE BPF_TO_BE - -/* jmp encodings */ -#define BPF_JNE 0x50 /* jump != */ -#define BPF_JLT 0xa0 /* LT is unsigned, '<' */ -#define BPF_JLE 0xb0 /* LE is unsigned, '<=' */ -#define BPF_JSGT 0x60 /* SGT is signed '>', GT in x86 */ -#define BPF_JSGE 0x70 /* SGE is signed '>=', GE in x86 */ -#define BPF_JSLT 0xc0 /* SLT is signed, '<' */ -#define BPF_JSLE 0xd0 /* SLE is signed, '<=' */ -#define BPF_CALL 0x80 /* function call */ -#define BPF_EXIT 0x90 /* function return */ - -/* Register numbers */ -enum { - BPF_REG_0 = 0, - BPF_REG_1, - BPF_REG_2, - BPF_REG_3, - BPF_REG_4, - BPF_REG_5, - BPF_REG_6, - BPF_REG_7, - BPF_REG_8, - BPF_REG_9, - BPF_REG_10, - __MAX_BPF_REG, -}; - -/* BPF has 10 general purpose 64-bit registers and stack frame. */ -#define MAX_BPF_REG __MAX_BPF_REG - -struct bpf_insn { - __u8 code; /* opcode */ - __u8 dst_reg:4; /* dest register */ - __u8 src_reg:4; /* source register */ - __s16 off; /* signed offset */ - __s32 imm; /* signed immediate constant */ -}; - -/* Key of an a BPF_MAP_TYPE_LPM_TRIE entry */ -struct bpf_lpm_trie_key { - __u32 prefixlen; /* up to 32 for AF_INET, 128 for AF_INET6 */ - __u8 data[0]; /* Arbitrary size */ -}; - -struct bpf_cgroup_storage_key { - __u64 cgroup_inode_id; /* cgroup inode id */ - __u32 attach_type; /* program attach type */ -}; - -/* BPF syscall commands, see bpf(2) man-page for details. */ -enum bpf_cmd { - BPF_MAP_CREATE, - BPF_MAP_LOOKUP_ELEM, - BPF_MAP_UPDATE_ELEM, - BPF_MAP_DELETE_ELEM, - BPF_MAP_GET_NEXT_KEY, - BPF_PROG_LOAD, - BPF_OBJ_PIN, - BPF_OBJ_GET, - BPF_PROG_ATTACH, - BPF_PROG_DETACH, - BPF_PROG_TEST_RUN, - BPF_PROG_GET_NEXT_ID, - BPF_MAP_GET_NEXT_ID, - BPF_PROG_GET_FD_BY_ID, - BPF_MAP_GET_FD_BY_ID, - BPF_OBJ_GET_INFO_BY_FD, - BPF_PROG_QUERY, - BPF_RAW_TRACEPOINT_OPEN, - BPF_BTF_LOAD, - BPF_BTF_GET_FD_BY_ID, - BPF_TASK_FD_QUERY, - BPF_MAP_LOOKUP_AND_DELETE_ELEM, -}; - -enum bpf_map_type { - BPF_MAP_TYPE_UNSPEC, - BPF_MAP_TYPE_HASH, - BPF_MAP_TYPE_ARRAY, - BPF_MAP_TYPE_PROG_ARRAY, - BPF_MAP_TYPE_PERF_EVENT_ARRAY, - BPF_MAP_TYPE_PERCPU_HASH, - BPF_MAP_TYPE_PERCPU_ARRAY, - BPF_MAP_TYPE_STACK_TRACE, - BPF_MAP_TYPE_CGROUP_ARRAY, - BPF_MAP_TYPE_LRU_HASH, - BPF_MAP_TYPE_LRU_PERCPU_HASH, - BPF_MAP_TYPE_LPM_TRIE, - BPF_MAP_TYPE_ARRAY_OF_MAPS, - BPF_MAP_TYPE_HASH_OF_MAPS, - BPF_MAP_TYPE_DEVMAP, - BPF_MAP_TYPE_SOCKMAP, - BPF_MAP_TYPE_CPUMAP, - BPF_MAP_TYPE_XSKMAP, - BPF_MAP_TYPE_SOCKHASH, - BPF_MAP_TYPE_CGROUP_STORAGE, - BPF_MAP_TYPE_REUSEPORT_SOCKARRAY, - BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE, - BPF_MAP_TYPE_QUEUE, - BPF_MAP_TYPE_STACK, -}; - -/* Note that tracing related programs such as - * BPF_PROG_TYPE_{KPROBE,TRACEPOINT,PERF_EVENT,RAW_TRACEPOINT} - * are not subject to a stable API since kernel internal data - * structures can change from release to release and may - * therefore break existing tracing BPF programs. Tracing BPF - * programs correspond to /a/ specific kernel which is to be - * analyzed, and not /a/ specific kernel /and/ all future ones. - */ -enum bpf_prog_type { - BPF_PROG_TYPE_UNSPEC, - BPF_PROG_TYPE_SOCKET_FILTER, - BPF_PROG_TYPE_KPROBE, - BPF_PROG_TYPE_SCHED_CLS, - BPF_PROG_TYPE_SCHED_ACT, - BPF_PROG_TYPE_TRACEPOINT, - BPF_PROG_TYPE_XDP, - BPF_PROG_TYPE_PERF_EVENT, - BPF_PROG_TYPE_CGROUP_SKB, - BPF_PROG_TYPE_CGROUP_SOCK, - BPF_PROG_TYPE_LWT_IN, - BPF_PROG_TYPE_LWT_OUT, - BPF_PROG_TYPE_LWT_XMIT, - BPF_PROG_TYPE_SOCK_OPS, - BPF_PROG_TYPE_SK_SKB, - BPF_PROG_TYPE_CGROUP_DEVICE, - BPF_PROG_TYPE_SK_MSG, - BPF_PROG_TYPE_RAW_TRACEPOINT, - BPF_PROG_TYPE_CGROUP_SOCK_ADDR, - BPF_PROG_TYPE_LWT_SEG6LOCAL, - BPF_PROG_TYPE_LIRC_MODE2, - BPF_PROG_TYPE_SK_REUSEPORT, - BPF_PROG_TYPE_FLOW_DISSECTOR, -}; - -enum bpf_attach_type { - BPF_CGROUP_INET_INGRESS, - BPF_CGROUP_INET_EGRESS, - BPF_CGROUP_INET_SOCK_CREATE, - BPF_CGROUP_SOCK_OPS, - BPF_SK_SKB_STREAM_PARSER, - BPF_SK_SKB_STREAM_VERDICT, - BPF_CGROUP_DEVICE, - BPF_SK_MSG_VERDICT, - BPF_CGROUP_INET4_BIND, - BPF_CGROUP_INET6_BIND, - BPF_CGROUP_INET4_CONNECT, - BPF_CGROUP_INET6_CONNECT, - BPF_CGROUP_INET4_POST_BIND, - BPF_CGROUP_INET6_POST_BIND, - BPF_CGROUP_UDP4_SENDMSG, - BPF_CGROUP_UDP6_SENDMSG, - BPF_LIRC_MODE2, - BPF_FLOW_DISSECTOR, - __MAX_BPF_ATTACH_TYPE -}; - -#define MAX_BPF_ATTACH_TYPE __MAX_BPF_ATTACH_TYPE - -/* cgroup-bpf attach flags used in BPF_PROG_ATTACH command - * - * NONE(default): No further bpf programs allowed in the subtree. - * - * BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program, - * the program in this cgroup yields to sub-cgroup program. - * - * BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program, - * that cgroup program gets run in addition to the program in this cgroup. - * - * Only one program is allowed to be attached to a cgroup with - * NONE or BPF_F_ALLOW_OVERRIDE flag. - * Attaching another program on top of NONE or BPF_F_ALLOW_OVERRIDE will - * release old program and attach the new one. Attach flags has to match. - * - * Multiple programs are allowed to be attached to a cgroup with - * BPF_F_ALLOW_MULTI flag. They are executed in FIFO order - * (those that were attached first, run first) - * The programs of sub-cgroup are executed first, then programs of - * this cgroup and then programs of parent cgroup. - * When children program makes decision (like picking TCP CA or sock bind) - * parent program has a chance to override it. - * - * A cgroup with MULTI or OVERRIDE flag allows any attach flags in sub-cgroups. - * A cgroup with NONE doesn't allow any programs in sub-cgroups. - * Ex1: - * cgrp1 (MULTI progs A, B) -> - * cgrp2 (OVERRIDE prog C) -> - * cgrp3 (MULTI prog D) -> - * cgrp4 (OVERRIDE prog E) -> - * cgrp5 (NONE prog F) - * the event in cgrp5 triggers execution of F,D,A,B in that order. - * if prog F is detached, the execution is E,D,A,B - * if prog F and D are detached, the execution is E,A,B - * if prog F, E and D are detached, the execution is C,A,B - * - * All eligible programs are executed regardless of return code from - * earlier programs. - */ -#define BPF_F_ALLOW_OVERRIDE (1U << 0) -#define BPF_F_ALLOW_MULTI (1U << 1) - -/* If BPF_F_STRICT_ALIGNMENT is used in BPF_PROG_LOAD command, the - * verifier will perform strict alignment checking as if the kernel - * has been built with CONFIG_EFFICIENT_UNALIGNED_ACCESS not set, - * and NET_IP_ALIGN defined to 2. - */ -#define BPF_F_STRICT_ALIGNMENT (1U << 0) - -/* If BPF_F_ANY_ALIGNMENT is used in BPF_PROF_LOAD command, the - * verifier will allow any alignment whatsoever. On platforms - * with strict alignment requirements for loads ands stores (such - * as sparc and mips) the verifier validates that all loads and - * stores provably follow this requirement. This flag turns that - * checking and enforcement off. - * - * It is mostly used for testing when we want to validate the - * context and memory access aspects of the verifier, but because - * of an unaligned access the alignment check would trigger before - * the one we are interested in. - */ -#define BPF_F_ANY_ALIGNMENT (1U << 1) - -/* when bpf_ldimm64->src_reg == BPF_PSEUDO_MAP_FD, bpf_ldimm64->imm == fd */ -#define BPF_PSEUDO_MAP_FD 1 - -/* when bpf_call->src_reg == BPF_PSEUDO_CALL, bpf_call->imm == pc-relative - * offset to another bpf function - */ -#define BPF_PSEUDO_CALL 1 - -/* flags for BPF_MAP_UPDATE_ELEM command */ -#define BPF_ANY 0 /* create new element or update existing */ -#define BPF_NOEXIST 1 /* create new element if it didn't exist */ -#define BPF_EXIST 2 /* update existing element */ -#define BPF_F_LOCK 4 /* spin_lock-ed map_lookup/map_update */ - -/* flags for BPF_MAP_CREATE command */ -#define BPF_F_NO_PREALLOC (1U << 0) -/* Instead of having one common LRU list in the - * BPF_MAP_TYPE_LRU_[PERCPU_]HASH map, use a percpu LRU list - * which can scale and perform better. - * Note, the LRU nodes (including free nodes) cannot be moved - * across different LRU lists. - */ -#define BPF_F_NO_COMMON_LRU (1U << 1) -/* Specify numa node during map creation */ -#define BPF_F_NUMA_NODE (1U << 2) - -#define BPF_OBJ_NAME_LEN 16U - -/* Flags for accessing BPF object */ -#define BPF_F_RDONLY (1U << 3) -#define BPF_F_WRONLY (1U << 4) - -/* Flag for stack_map, store build_id+offset instead of pointer */ -#define BPF_F_STACK_BUILD_ID (1U << 5) - -/* Zero-initialize hash function seed. This should only be used for testing. */ -#define BPF_F_ZERO_SEED (1U << 6) - -/* flags for BPF_PROG_QUERY */ -#define BPF_F_QUERY_EFFECTIVE (1U << 0) - -enum bpf_stack_build_id_status { - /* user space need an empty entry to identify end of a trace */ - BPF_STACK_BUILD_ID_EMPTY = 0, - /* with valid build_id and offset */ - BPF_STACK_BUILD_ID_VALID = 1, - /* couldn't get build_id, fallback to ip */ - BPF_STACK_BUILD_ID_IP = 2, -}; - -#define BPF_BUILD_ID_SIZE 20 -struct bpf_stack_build_id { - __s32 status; - unsigned char build_id[BPF_BUILD_ID_SIZE]; - union { - __u64 offset; - __u64 ip; - }; -}; - -union bpf_attr { - struct { /* anonymous struct used by BPF_MAP_CREATE command */ - __u32 map_type; /* one of enum bpf_map_type */ - __u32 key_size; /* size of key in bytes */ - __u32 value_size; /* size of value in bytes */ - __u32 max_entries; /* max number of entries in a map */ - __u32 map_flags; /* BPF_MAP_CREATE related - * flags defined above. - */ - __u32 inner_map_fd; /* fd pointing to the inner map */ - __u32 numa_node; /* numa node (effective only if - * BPF_F_NUMA_NODE is set). - */ - char map_name[BPF_OBJ_NAME_LEN]; - __u32 map_ifindex; /* ifindex of netdev to create on */ - __u32 btf_fd; /* fd pointing to a BTF type data */ - __u32 btf_key_type_id; /* BTF type_id of the key */ - __u32 btf_value_type_id; /* BTF type_id of the value */ - }; - - struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */ - __u32 map_fd; - __aligned_u64 key; - union { - __aligned_u64 value; - __aligned_u64 next_key; - }; - __u64 flags; - }; - - struct { /* anonymous struct used by BPF_PROG_LOAD command */ - __u32 prog_type; /* one of enum bpf_prog_type */ - __u32 insn_cnt; - __aligned_u64 insns; - __aligned_u64 license; - __u32 log_level; /* verbosity level of verifier */ - __u32 log_size; /* size of user buffer */ - __aligned_u64 log_buf; /* user supplied buffer */ - __u32 kern_version; /* not used */ - __u32 prog_flags; - char prog_name[BPF_OBJ_NAME_LEN]; - __u32 prog_ifindex; /* ifindex of netdev to prep for */ - /* For some prog types expected attach type must be known at - * load time to verify attach type specific parts of prog - * (context accesses, allowed helpers, etc). - */ - __u32 expected_attach_type; - __u32 prog_btf_fd; /* fd pointing to BTF type data */ - __u32 func_info_rec_size; /* userspace bpf_func_info size */ - __aligned_u64 func_info; /* func info */ - __u32 func_info_cnt; /* number of bpf_func_info records */ - __u32 line_info_rec_size; /* userspace bpf_line_info size */ - __aligned_u64 line_info; /* line info */ - __u32 line_info_cnt; /* number of bpf_line_info records */ - }; - - struct { /* anonymous struct used by BPF_OBJ_* commands */ - __aligned_u64 pathname; - __u32 bpf_fd; - __u32 file_flags; - }; - - struct { /* anonymous struct used by BPF_PROG_ATTACH/DETACH commands */ - __u32 target_fd; /* container object to attach to */ - __u32 attach_bpf_fd; /* eBPF program to attach */ - __u32 attach_type; - __u32 attach_flags; - }; - - struct { /* anonymous struct used by BPF_PROG_TEST_RUN command */ - __u32 prog_fd; - __u32 retval; - __u32 data_size_in; /* input: len of data_in */ - __u32 data_size_out; /* input/output: len of data_out - * returns ENOSPC if data_out - * is too small. - */ - __aligned_u64 data_in; - __aligned_u64 data_out; - __u32 repeat; - __u32 duration; - } test; - - struct { /* anonymous struct used by BPF_*_GET_*_ID */ - union { - __u32 start_id; - __u32 prog_id; - __u32 map_id; - __u32 btf_id; - }; - __u32 next_id; - __u32 open_flags; - }; - - struct { /* anonymous struct used by BPF_OBJ_GET_INFO_BY_FD */ - __u32 bpf_fd; - __u32 info_len; - __aligned_u64 info; - } info; - - struct { /* anonymous struct used by BPF_PROG_QUERY command */ - __u32 target_fd; /* container object to query */ - __u32 attach_type; - __u32 query_flags; - __u32 attach_flags; - __aligned_u64 prog_ids; - __u32 prog_cnt; - } query; - - struct { - __u64 name; - __u32 prog_fd; - } raw_tracepoint; - - struct { /* anonymous struct for BPF_BTF_LOAD */ - __aligned_u64 btf; - __aligned_u64 btf_log_buf; - __u32 btf_size; - __u32 btf_log_size; - __u32 btf_log_level; - }; - - struct { - __u32 pid; /* input: pid */ - __u32 fd; /* input: fd */ - __u32 flags; /* input: flags */ - __u32 buf_len; /* input/output: buf len */ - __aligned_u64 buf; /* input/output: - * tp_name for tracepoint - * symbol for kprobe - * filename for uprobe - */ - __u32 prog_id; /* output: prod_id */ - __u32 fd_type; /* output: BPF_FD_TYPE_* */ - __u64 probe_offset; /* output: probe_offset */ - __u64 probe_addr; /* output: probe_addr */ - } task_fd_query; -} __attribute__((aligned(8))); - -/* The description below is an attempt at providing documentation to eBPF - * developers about the multiple available eBPF helper functions. It can be - * parsed and used to produce a manual page. The workflow is the following, - * and requires the rst2man utility: - * - * $ ./scripts/bpf_helpers_doc.py \ - * --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst - * $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7 - * $ man /tmp/bpf-helpers.7 - * - * Note that in order to produce this external documentation, some RST - * formatting is used in the descriptions to get "bold" and "italics" in - * manual pages. Also note that the few trailing white spaces are - * intentional, removing them would break paragraphs for rst2man. - * - * Start of BPF helper function descriptions: - * - * void *bpf_map_lookup_elem(struct bpf_map *map, const void *key) - * Description - * Perform a lookup in *map* for an entry associated to *key*. - * Return - * Map value associated to *key*, or **NULL** if no entry was - * found. - * - * int bpf_map_update_elem(struct bpf_map *map, const void *key, const void *value, u64 flags) - * Description - * Add or update the value of the entry associated to *key* in - * *map* with *value*. *flags* is one of: - * - * **BPF_NOEXIST** - * The entry for *key* must not exist in the map. - * **BPF_EXIST** - * The entry for *key* must already exist in the map. - * **BPF_ANY** - * No condition on the existence of the entry for *key*. - * - * Flag value **BPF_NOEXIST** cannot be used for maps of types - * **BPF_MAP_TYPE_ARRAY** or **BPF_MAP_TYPE_PERCPU_ARRAY** (all - * elements always exist), the helper would return an error. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_map_delete_elem(struct bpf_map *map, const void *key) - * Description - * Delete entry with *key* from *map*. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_probe_read(void *dst, u32 size, const void *src) - * Description - * For tracing programs, safely attempt to read *size* bytes from - * address *src* and store the data in *dst*. - * Return - * 0 on success, or a negative error in case of failure. - * - * u64 bpf_ktime_get_ns(void) - * Description - * Return the time elapsed since system boot, in nanoseconds. - * Return - * Current *ktime*. - * - * int bpf_trace_printk(const char *fmt, u32 fmt_size, ...) - * Description - * This helper is a "printk()-like" facility for debugging. It - * prints a message defined by format *fmt* (of size *fmt_size*) - * to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if - * available. It can take up to three additional **u64** - * arguments (as an eBPF helpers, the total number of arguments is - * limited to five). - * - * Each time the helper is called, it appends a line to the trace. - * The format of the trace is customizable, and the exact output - * one will get depends on the options set in - * *\/sys/kernel/debug/tracing/trace_options* (see also the - * *README* file under the same directory). However, it usually - * defaults to something like: - * - * :: - * - * telnet-470 [001] .N.. 419421.045894: 0x00000001: <formatted msg> - * - * In the above: - * - * * ``telnet`` is the name of the current task. - * * ``470`` is the PID of the current task. - * * ``001`` is the CPU number on which the task is - * running. - * * In ``.N..``, each character refers to a set of - * options (whether irqs are enabled, scheduling - * options, whether hard/softirqs are running, level of - * preempt_disabled respectively). **N** means that - * **TIF_NEED_RESCHED** and **PREEMPT_NEED_RESCHED** - * are set. - * * ``419421.045894`` is a timestamp. - * * ``0x00000001`` is a fake value used by BPF for the - * instruction pointer register. - * * ``<formatted msg>`` is the message formatted with - * *fmt*. - * - * The conversion specifiers supported by *fmt* are similar, but - * more limited than for printk(). They are **%d**, **%i**, - * **%u**, **%x**, **%ld**, **%li**, **%lu**, **%lx**, **%lld**, - * **%lli**, **%llu**, **%llx**, **%p**, **%s**. No modifier (size - * of field, padding with zeroes, etc.) is available, and the - * helper will return **-EINVAL** (but print nothing) if it - * encounters an unknown specifier. - * - * Also, note that **bpf_trace_printk**\ () is slow, and should - * only be used for debugging purposes. For this reason, a notice - * bloc (spanning several lines) is printed to kernel logs and - * states that the helper should not be used "for production use" - * the first time this helper is used (or more precisely, when - * **trace_printk**\ () buffers are allocated). For passing values - * to user space, perf events should be preferred. - * Return - * The number of bytes written to the buffer, or a negative error - * in case of failure. - * - * u32 bpf_get_prandom_u32(void) - * Description - * Get a pseudo-random number. - * - * From a security point of view, this helper uses its own - * pseudo-random internal state, and cannot be used to infer the - * seed of other random functions in the kernel. However, it is - * essential to note that the generator used by the helper is not - * cryptographically secure. - * Return - * A random 32-bit unsigned value. - * - * u32 bpf_get_smp_processor_id(void) - * Description - * Get the SMP (symmetric multiprocessing) processor id. Note that - * all programs run with preemption disabled, which means that the - * SMP processor id is stable during all the execution of the - * program. - * Return - * The SMP id of the processor running the program. - * - * int bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len, u64 flags) - * Description - * Store *len* bytes from address *from* into the packet - * associated to *skb*, at *offset*. *flags* are a combination of - * **BPF_F_RECOMPUTE_CSUM** (automatically recompute the - * checksum for the packet after storing the bytes) and - * **BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\ - * **->swhash** and *skb*\ **->l4hash** to 0). - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_l3_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 size) - * Description - * Recompute the layer 3 (e.g. IP) checksum for the packet - * associated to *skb*. Computation is incremental, so the helper - * must know the former value of the header field that was - * modified (*from*), the new value of this field (*to*), and the - * number of bytes (2 or 4) for this field, stored in *size*. - * Alternatively, it is possible to store the difference between - * the previous and the new values of the header field in *to*, by - * setting *from* and *size* to 0. For both methods, *offset* - * indicates the location of the IP checksum within the packet. - * - * This helper works in combination with **bpf_csum_diff**\ (), - * which does not update the checksum in-place, but offers more - * flexibility and can handle sizes larger than 2 or 4 for the - * checksum to update. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_l4_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 flags) - * Description - * Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the - * packet associated to *skb*. Computation is incremental, so the - * helper must know the former value of the header field that was - * modified (*from*), the new value of this field (*to*), and the - * number of bytes (2 or 4) for this field, stored on the lowest - * four bits of *flags*. Alternatively, it is possible to store - * the difference between the previous and the new values of the - * header field in *to*, by setting *from* and the four lowest - * bits of *flags* to 0. For both methods, *offset* indicates the - * location of the IP checksum within the packet. In addition to - * the size of the field, *flags* can be added (bitwise OR) actual - * flags. With **BPF_F_MARK_MANGLED_0**, a null checksum is left - * untouched (unless **BPF_F_MARK_ENFORCE** is added as well), and - * for updates resulting in a null checksum the value is set to - * **CSUM_MANGLED_0** instead. Flag **BPF_F_PSEUDO_HDR** indicates - * the checksum is to be computed against a pseudo-header. - * - * This helper works in combination with **bpf_csum_diff**\ (), - * which does not update the checksum in-place, but offers more - * flexibility and can handle sizes larger than 2 or 4 for the - * checksum to update. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_tail_call(void *ctx, struct bpf_map *prog_array_map, u32 index) - * Description - * This special helper is used to trigger a "tail call", or in - * other words, to jump into another eBPF program. The same stack - * frame is used (but values on stack and in registers for the - * caller are not accessible to the callee). This mechanism allows - * for program chaining, either for raising the maximum number of - * available eBPF instructions, or to execute given programs in - * conditional blocks. For security reasons, there is an upper - * limit to the number of successive tail calls that can be - * performed. - * - * Upon call of this helper, the program attempts to jump into a - * program referenced at index *index* in *prog_array_map*, a - * special map of type **BPF_MAP_TYPE_PROG_ARRAY**, and passes - * *ctx*, a pointer to the context. - * - * If the call succeeds, the kernel immediately runs the first - * instruction of the new program. This is not a function call, - * and it never returns to the previous program. If the call - * fails, then the helper has no effect, and the caller continues - * to run its subsequent instructions. A call can fail if the - * destination program for the jump does not exist (i.e. *index* - * is superior to the number of entries in *prog_array_map*), or - * if the maximum number of tail calls has been reached for this - * chain of programs. This limit is defined in the kernel by the - * macro **MAX_TAIL_CALL_CNT** (not accessible to user space), - * which is currently set to 32. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_clone_redirect(struct sk_buff *skb, u32 ifindex, u64 flags) - * Description - * Clone and redirect the packet associated to *skb* to another - * net device of index *ifindex*. Both ingress and egress - * interfaces can be used for redirection. The **BPF_F_INGRESS** - * value in *flags* is used to make the distinction (ingress path - * is selected if the flag is present, egress path otherwise). - * This is the only flag supported for now. - * - * In comparison with **bpf_redirect**\ () helper, - * **bpf_clone_redirect**\ () has the associated cost of - * duplicating the packet buffer, but this can be executed out of - * the eBPF program. Conversely, **bpf_redirect**\ () is more - * efficient, but it is handled through an action code where the - * redirection happens only after the eBPF program has returned. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * u64 bpf_get_current_pid_tgid(void) - * Return - * A 64-bit integer containing the current tgid and pid, and - * created as such: - * *current_task*\ **->tgid << 32 \|** - * *current_task*\ **->pid**. - * - * u64 bpf_get_current_uid_gid(void) - * Return - * A 64-bit integer containing the current GID and UID, and - * created as such: *current_gid* **<< 32 \|** *current_uid*. - * - * int bpf_get_current_comm(char *buf, u32 size_of_buf) - * Description - * Copy the **comm** attribute of the current task into *buf* of - * *size_of_buf*. The **comm** attribute contains the name of - * the executable (excluding the path) for the current task. The - * *size_of_buf* must be strictly positive. On success, the - * helper makes sure that the *buf* is NUL-terminated. On failure, - * it is filled with zeroes. - * Return - * 0 on success, or a negative error in case of failure. - * - * u32 bpf_get_cgroup_classid(struct sk_buff *skb) - * Description - * Retrieve the classid for the current task, i.e. for the net_cls - * cgroup to which *skb* belongs. - * - * This helper can be used on TC egress path, but not on ingress. - * - * The net_cls cgroup provides an interface to tag network packets - * based on a user-provided identifier for all traffic coming from - * the tasks belonging to the related cgroup. See also the related - * kernel documentation, available from the Linux sources in file - * *Documentation/cgroup-v1/net_cls.txt*. - * - * The Linux kernel has two versions for cgroups: there are - * cgroups v1 and cgroups v2. Both are available to users, who can - * use a mixture of them, but note that the net_cls cgroup is for - * cgroup v1 only. This makes it incompatible with BPF programs - * run on cgroups, which is a cgroup-v2-only feature (a socket can - * only hold data for one version of cgroups at a time). - * - * This helper is only available is the kernel was compiled with - * the **CONFIG_CGROUP_NET_CLASSID** configuration option set to - * "**y**" or to "**m**". - * Return - * The classid, or 0 for the default unconfigured classid. - * - * int bpf_skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci) - * Description - * Push a *vlan_tci* (VLAN tag control information) of protocol - * *vlan_proto* to the packet associated to *skb*, then update - * the checksum. Note that if *vlan_proto* is different from - * **ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to - * be **ETH_P_8021Q**. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_vlan_pop(struct sk_buff *skb) - * Description - * Pop a VLAN header from the packet associated to *skb*. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_get_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags) - * Description - * Get tunnel metadata. This helper takes a pointer *key* to an - * empty **struct bpf_tunnel_key** of **size**, that will be - * filled with tunnel metadata for the packet associated to *skb*. - * The *flags* can be set to **BPF_F_TUNINFO_IPV6**, which - * indicates that the tunnel is based on IPv6 protocol instead of - * IPv4. - * - * The **struct bpf_tunnel_key** is an object that generalizes the - * principal parameters used by various tunneling protocols into a - * single struct. This way, it can be used to easily make a - * decision based on the contents of the encapsulation header, - * "summarized" in this struct. In particular, it holds the IP - * address of the remote end (IPv4 or IPv6, depending on the case) - * in *key*\ **->remote_ipv4** or *key*\ **->remote_ipv6**. Also, - * this struct exposes the *key*\ **->tunnel_id**, which is - * generally mapped to a VNI (Virtual Network Identifier), making - * it programmable together with the **bpf_skb_set_tunnel_key**\ - * () helper. - * - * Let's imagine that the following code is part of a program - * attached to the TC ingress interface, on one end of a GRE - * tunnel, and is supposed to filter out all messages coming from - * remote ends with IPv4 address other than 10.0.0.1: - * - * :: - * - * int ret; - * struct bpf_tunnel_key key = {}; - * - * ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0); - * if (ret < 0) - * return TC_ACT_SHOT; // drop packet - * - * if (key.remote_ipv4 != 0x0a000001) - * return TC_ACT_SHOT; // drop packet - * - * return TC_ACT_OK; // accept packet - * - * This interface can also be used with all encapsulation devices - * that can operate in "collect metadata" mode: instead of having - * one network device per specific configuration, the "collect - * metadata" mode only requires a single device where the - * configuration can be extracted from this helper. - * - * This can be used together with various tunnels such as VXLan, - * Geneve, GRE or IP in IP (IPIP). - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_set_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags) - * Description - * Populate tunnel metadata for packet associated to *skb.* The - * tunnel metadata is set to the contents of *key*, of *size*. The - * *flags* can be set to a combination of the following values: - * - * **BPF_F_TUNINFO_IPV6** - * Indicate that the tunnel is based on IPv6 protocol - * instead of IPv4. - * **BPF_F_ZERO_CSUM_TX** - * For IPv4 packets, add a flag to tunnel metadata - * indicating that checksum computation should be skipped - * and checksum set to zeroes. - * **BPF_F_DONT_FRAGMENT** - * Add a flag to tunnel metadata indicating that the - * packet should not be fragmented. - * **BPF_F_SEQ_NUMBER** - * Add a flag to tunnel metadata indicating that a - * sequence number should be added to tunnel header before - * sending the packet. This flag was added for GRE - * encapsulation, but might be used with other protocols - * as well in the future. - * - * Here is a typical usage on the transmit path: - * - * :: - * - * struct bpf_tunnel_key key; - * populate key ... - * bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0); - * bpf_clone_redirect(skb, vxlan_dev_ifindex, 0); - * - * See also the description of the **bpf_skb_get_tunnel_key**\ () - * helper for additional information. - * Return - * 0 on success, or a negative error in case of failure. - * - * u64 bpf_perf_event_read(struct bpf_map *map, u64 flags) - * Description - * Read the value of a perf event counter. This helper relies on a - * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of - * the perf event counter is selected when *map* is updated with - * perf event file descriptors. The *map* is an array whose size - * is the number of available CPUs, and each cell contains a value - * relative to one CPU. The value to retrieve is indicated by - * *flags*, that contains the index of the CPU to look up, masked - * with **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to - * **BPF_F_CURRENT_CPU** to indicate that the value for the - * current CPU should be retrieved. - * - * Note that before Linux 4.13, only hardware perf event can be - * retrieved. - * - * Also, be aware that the newer helper - * **bpf_perf_event_read_value**\ () is recommended over - * **bpf_perf_event_read**\ () in general. The latter has some ABI - * quirks where error and counter value are used as a return code - * (which is wrong to do since ranges may overlap). This issue is - * fixed with **bpf_perf_event_read_value**\ (), which at the same - * time provides more features over the **bpf_perf_event_read**\ - * () interface. Please refer to the description of - * **bpf_perf_event_read_value**\ () for details. - * Return - * The value of the perf event counter read from the map, or a - * negative error code in case of failure. - * - * int bpf_redirect(u32 ifindex, u64 flags) - * Description - * Redirect the packet to another net device of index *ifindex*. - * This helper is somewhat similar to **bpf_clone_redirect**\ - * (), except that the packet is not cloned, which provides - * increased performance. - * - * Except for XDP, both ingress and egress interfaces can be used - * for redirection. The **BPF_F_INGRESS** value in *flags* is used - * to make the distinction (ingress path is selected if the flag - * is present, egress path otherwise). Currently, XDP only - * supports redirection to the egress interface, and accepts no - * flag at all. - * - * The same effect can be attained with the more generic - * **bpf_redirect_map**\ (), which requires specific maps to be - * used but offers better performance. - * Return - * For XDP, the helper returns **XDP_REDIRECT** on success or - * **XDP_ABORTED** on error. For other program types, the values - * are **TC_ACT_REDIRECT** on success or **TC_ACT_SHOT** on - * error. - * - * u32 bpf_get_route_realm(struct sk_buff *skb) - * Description - * Retrieve the realm or the route, that is to say the - * **tclassid** field of the destination for the *skb*. The - * indentifier retrieved is a user-provided tag, similar to the - * one used with the net_cls cgroup (see description for - * **bpf_get_cgroup_classid**\ () helper), but here this tag is - * held by a route (a destination entry), not by a task. - * - * Retrieving this identifier works with the clsact TC egress hook - * (see also **tc-bpf(8)**), or alternatively on conventional - * classful egress qdiscs, but not on TC ingress path. In case of - * clsact TC egress hook, this has the advantage that, internally, - * the destination entry has not been dropped yet in the transmit - * path. Therefore, the destination entry does not need to be - * artificially held via **netif_keep_dst**\ () for a classful - * qdisc until the *skb* is freed. - * - * This helper is available only if the kernel was compiled with - * **CONFIG_IP_ROUTE_CLASSID** configuration option. - * Return - * The realm of the route for the packet associated to *skb*, or 0 - * if none was found. - * - * int bpf_perf_event_output(struct pt_reg *ctx, struct bpf_map *map, u64 flags, void *data, u64 size) - * Description - * Write raw *data* blob into a special BPF perf event held by - * *map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf - * event must have the following attributes: **PERF_SAMPLE_RAW** - * as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and - * **PERF_COUNT_SW_BPF_OUTPUT** as **config**. - * - * The *flags* are used to indicate the index in *map* for which - * the value must be put, masked with **BPF_F_INDEX_MASK**. - * Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU** - * to indicate that the index of the current CPU core should be - * used. - * - * The value to write, of *size*, is passed through eBPF stack and - * pointed by *data*. - * - * The context of the program *ctx* needs also be passed to the - * helper. - * - * On user space, a program willing to read the values needs to - * call **perf_event_open**\ () on the perf event (either for - * one or for all CPUs) and to store the file descriptor into the - * *map*. This must be done before the eBPF program can send data - * into it. An example is available in file - * *samples/bpf/trace_output_user.c* in the Linux kernel source - * tree (the eBPF program counterpart is in - * *samples/bpf/trace_output_kern.c*). - * - * **bpf_perf_event_output**\ () achieves better performance - * than **bpf_trace_printk**\ () for sharing data with user - * space, and is much better suitable for streaming data from eBPF - * programs. - * - * Note that this helper is not restricted to tracing use cases - * and can be used with programs attached to TC or XDP as well, - * where it allows for passing data to user space listeners. Data - * can be: - * - * * Only custom structs, - * * Only the packet payload, or - * * A combination of both. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len) - * Description - * This helper was provided as an easy way to load data from a - * packet. It can be used to load *len* bytes from *offset* from - * the packet associated to *skb*, into the buffer pointed by - * *to*. - * - * Since Linux 4.7, usage of this helper has mostly been replaced - * by "direct packet access", enabling packet data to be - * manipulated with *skb*\ **->data** and *skb*\ **->data_end** - * pointing respectively to the first byte of packet data and to - * the byte after the last byte of packet data. However, it - * remains useful if one wishes to read large quantities of data - * at once from a packet into the eBPF stack. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_get_stackid(struct pt_reg *ctx, struct bpf_map *map, u64 flags) - * Description - * Walk a user or a kernel stack and return its id. To achieve - * this, the helper needs *ctx*, which is a pointer to the context - * on which the tracing program is executed, and a pointer to a - * *map* of type **BPF_MAP_TYPE_STACK_TRACE**. - * - * The last argument, *flags*, holds the number of stack frames to - * skip (from 0 to 255), masked with - * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set - * a combination of the following flags: - * - * **BPF_F_USER_STACK** - * Collect a user space stack instead of a kernel stack. - * **BPF_F_FAST_STACK_CMP** - * Compare stacks by hash only. - * **BPF_F_REUSE_STACKID** - * If two different stacks hash into the same *stackid*, - * discard the old one. - * - * The stack id retrieved is a 32 bit long integer handle which - * can be further combined with other data (including other stack - * ids) and used as a key into maps. This can be useful for - * generating a variety of graphs (such as flame graphs or off-cpu - * graphs). - * - * For walking a stack, this helper is an improvement over - * **bpf_probe_read**\ (), which can be used with unrolled loops - * but is not efficient and consumes a lot of eBPF instructions. - * Instead, **bpf_get_stackid**\ () can collect up to - * **PERF_MAX_STACK_DEPTH** both kernel and user frames. Note that - * this limit can be controlled with the **sysctl** program, and - * that it should be manually increased in order to profile long - * user stacks (such as stacks for Java programs). To do so, use: - * - * :: - * - * # sysctl kernel.perf_event_max_stack=<new value> - * Return - * The positive or null stack id on success, or a negative error - * in case of failure. - * - * s64 bpf_csum_diff(__be32 *from, u32 from_size, __be32 *to, u32 to_size, __wsum seed) - * Description - * Compute a checksum difference, from the raw buffer pointed by - * *from*, of length *from_size* (that must be a multiple of 4), - * towards the raw buffer pointed by *to*, of size *to_size* - * (same remark). An optional *seed* can be added to the value - * (this can be cascaded, the seed may come from a previous call - * to the helper). - * - * This is flexible enough to be used in several ways: - * - * * With *from_size* == 0, *to_size* > 0 and *seed* set to - * checksum, it can be used when pushing new data. - * * With *from_size* > 0, *to_size* == 0 and *seed* set to - * checksum, it can be used when removing data from a packet. - * * With *from_size* > 0, *to_size* > 0 and *seed* set to 0, it - * can be used to compute a diff. Note that *from_size* and - * *to_size* do not need to be equal. - * - * This helper can be used in combination with - * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ (), to - * which one can feed in the difference computed with - * **bpf_csum_diff**\ (). - * Return - * The checksum result, or a negative error code in case of - * failure. - * - * int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size) - * Description - * Retrieve tunnel options metadata for the packet associated to - * *skb*, and store the raw tunnel option data to the buffer *opt* - * of *size*. - * - * This helper can be used with encapsulation devices that can - * operate in "collect metadata" mode (please refer to the related - * note in the description of **bpf_skb_get_tunnel_key**\ () for - * more details). A particular example where this can be used is - * in combination with the Geneve encapsulation protocol, where it - * allows for pushing (with **bpf_skb_get_tunnel_opt**\ () helper) - * and retrieving arbitrary TLVs (Type-Length-Value headers) from - * the eBPF program. This allows for full customization of these - * headers. - * Return - * The size of the option data retrieved. - * - * int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size) - * Description - * Set tunnel options metadata for the packet associated to *skb* - * to the option data contained in the raw buffer *opt* of *size*. - * - * See also the description of the **bpf_skb_get_tunnel_opt**\ () - * helper for additional information. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_change_proto(struct sk_buff *skb, __be16 proto, u64 flags) - * Description - * Change the protocol of the *skb* to *proto*. Currently - * supported are transition from IPv4 to IPv6, and from IPv6 to - * IPv4. The helper takes care of the groundwork for the - * transition, including resizing the socket buffer. The eBPF - * program is expected to fill the new headers, if any, via - * **skb_store_bytes**\ () and to recompute the checksums with - * **bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ - * (). The main case for this helper is to perform NAT64 - * operations out of an eBPF program. - * - * Internally, the GSO type is marked as dodgy so that headers are - * checked and segments are recalculated by the GSO/GRO engine. - * The size for GSO target is adapted as well. - * - * All values for *flags* are reserved for future usage, and must - * be left at zero. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_change_type(struct sk_buff *skb, u32 type) - * Description - * Change the packet type for the packet associated to *skb*. This - * comes down to setting *skb*\ **->pkt_type** to *type*, except - * the eBPF program does not have a write access to *skb*\ - * **->pkt_type** beside this helper. Using a helper here allows - * for graceful handling of errors. - * - * The major use case is to change incoming *skb*s to - * **PACKET_HOST** in a programmatic way instead of having to - * recirculate via **redirect**\ (..., **BPF_F_INGRESS**), for - * example. - * - * Note that *type* only allows certain values. At this time, they - * are: - * - * **PACKET_HOST** - * Packet is for us. - * **PACKET_BROADCAST** - * Send packet to all. - * **PACKET_MULTICAST** - * Send packet to group. - * **PACKET_OTHERHOST** - * Send packet to someone else. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_under_cgroup(struct sk_buff *skb, struct bpf_map *map, u32 index) - * Description - * Check whether *skb* is a descendant of the cgroup2 held by - * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. - * Return - * The return value depends on the result of the test, and can be: - * - * * 0, if the *skb* failed the cgroup2 descendant test. - * * 1, if the *skb* succeeded the cgroup2 descendant test. - * * A negative error code, if an error occurred. - * - * u32 bpf_get_hash_recalc(struct sk_buff *skb) - * Description - * Retrieve the hash of the packet, *skb*\ **->hash**. If it is - * not set, in particular if the hash was cleared due to mangling, - * recompute this hash. Later accesses to the hash can be done - * directly with *skb*\ **->hash**. - * - * Calling **bpf_set_hash_invalid**\ (), changing a packet - * prototype with **bpf_skb_change_proto**\ (), or calling - * **bpf_skb_store_bytes**\ () with the - * **BPF_F_INVALIDATE_HASH** are actions susceptible to clear - * the hash and to trigger a new computation for the next call to - * **bpf_get_hash_recalc**\ (). - * Return - * The 32-bit hash. - * - * u64 bpf_get_current_task(void) - * Return - * A pointer to the current task struct. - * - * int bpf_probe_write_user(void *dst, const void *src, u32 len) - * Description - * Attempt in a safe way to write *len* bytes from the buffer - * *src* to *dst* in memory. It only works for threads that are in - * user context, and *dst* must be a valid user space address. - * - * This helper should not be used to implement any kind of - * security mechanism because of TOC-TOU attacks, but rather to - * debug, divert, and manipulate execution of semi-cooperative - * processes. - * - * Keep in mind that this feature is meant for experiments, and it - * has a risk of crashing the system and running programs. - * Therefore, when an eBPF program using this helper is attached, - * a warning including PID and process name is printed to kernel - * logs. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_current_task_under_cgroup(struct bpf_map *map, u32 index) - * Description - * Check whether the probe is being run is the context of a given - * subset of the cgroup2 hierarchy. The cgroup2 to test is held by - * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. - * Return - * The return value depends on the result of the test, and can be: - * - * * 0, if the *skb* task belongs to the cgroup2. - * * 1, if the *skb* task does not belong to the cgroup2. - * * A negative error code, if an error occurred. - * - * int bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags) - * Description - * Resize (trim or grow) the packet associated to *skb* to the - * new *len*. The *flags* are reserved for future usage, and must - * be left at zero. - * - * The basic idea is that the helper performs the needed work to - * change the size of the packet, then the eBPF program rewrites - * the rest via helpers like **bpf_skb_store_bytes**\ (), - * **bpf_l3_csum_replace**\ (), **bpf_l3_csum_replace**\ () - * and others. This helper is a slow path utility intended for - * replies with control messages. And because it is targeted for - * slow path, the helper itself can afford to be slow: it - * implicitly linearizes, unclones and drops offloads from the - * *skb*. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_pull_data(struct sk_buff *skb, u32 len) - * Description - * Pull in non-linear data in case the *skb* is non-linear and not - * all of *len* are part of the linear section. Make *len* bytes - * from *skb* readable and writable. If a zero value is passed for - * *len*, then the whole length of the *skb* is pulled. - * - * This helper is only needed for reading and writing with direct - * packet access. - * - * For direct packet access, testing that offsets to access - * are within packet boundaries (test on *skb*\ **->data_end**) is - * susceptible to fail if offsets are invalid, or if the requested - * data is in non-linear parts of the *skb*. On failure the - * program can just bail out, or in the case of a non-linear - * buffer, use a helper to make the data available. The - * **bpf_skb_load_bytes**\ () helper is a first solution to access - * the data. Another one consists in using **bpf_skb_pull_data** - * to pull in once the non-linear parts, then retesting and - * eventually access the data. - * - * At the same time, this also makes sure the *skb* is uncloned, - * which is a necessary condition for direct write. As this needs - * to be an invariant for the write part only, the verifier - * detects writes and adds a prologue that is calling - * **bpf_skb_pull_data()** to effectively unclone the *skb* from - * the very beginning in case it is indeed cloned. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * s64 bpf_csum_update(struct sk_buff *skb, __wsum csum) - * Description - * Add the checksum *csum* into *skb*\ **->csum** in case the - * driver has supplied a checksum for the entire packet into that - * field. Return an error otherwise. This helper is intended to be - * used in combination with **bpf_csum_diff**\ (), in particular - * when the checksum needs to be updated after data has been - * written into the packet through direct packet access. - * Return - * The checksum on success, or a negative error code in case of - * failure. - * - * void bpf_set_hash_invalid(struct sk_buff *skb) - * Description - * Invalidate the current *skb*\ **->hash**. It can be used after - * mangling on headers through direct packet access, in order to - * indicate that the hash is outdated and to trigger a - * recalculation the next time the kernel tries to access this - * hash or when the **bpf_get_hash_recalc**\ () helper is called. - * - * int bpf_get_numa_node_id(void) - * Description - * Return the id of the current NUMA node. The primary use case - * for this helper is the selection of sockets for the local NUMA - * node, when the program is attached to sockets using the - * **SO_ATTACH_REUSEPORT_EBPF** option (see also **socket(7)**), - * but the helper is also available to other eBPF program types, - * similarly to **bpf_get_smp_processor_id**\ (). - * Return - * The id of current NUMA node. - * - * int bpf_skb_change_head(struct sk_buff *skb, u32 len, u64 flags) - * Description - * Grows headroom of packet associated to *skb* and adjusts the - * offset of the MAC header accordingly, adding *len* bytes of - * space. It automatically extends and reallocates memory as - * required. - * - * This helper can be used on a layer 3 *skb* to push a MAC header - * for redirection into a layer 2 device. - * - * All values for *flags* are reserved for future usage, and must - * be left at zero. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_xdp_adjust_head(struct xdp_buff *xdp_md, int delta) - * Description - * Adjust (move) *xdp_md*\ **->data** by *delta* bytes. Note that - * it is possible to use a negative value for *delta*. This helper - * can be used to prepare the packet for pushing or popping - * headers. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr) - * Description - * Copy a NUL terminated string from an unsafe address - * *unsafe_ptr* to *dst*. The *size* should include the - * terminating NUL byte. In case the string length is smaller than - * *size*, the target is not padded with further NUL bytes. If the - * string length is larger than *size*, just *size*-1 bytes are - * copied and the last byte is set to NUL. - * - * On success, the length of the copied string is returned. This - * makes this helper useful in tracing programs for reading - * strings, and more importantly to get its length at runtime. See - * the following snippet: - * - * :: - * - * SEC("kprobe/sys_open") - * void bpf_sys_open(struct pt_regs *ctx) - * { - * char buf[PATHLEN]; // PATHLEN is defined to 256 - * int res = bpf_probe_read_str(buf, sizeof(buf), - * ctx->di); - * - * // Consume buf, for example push it to - * // userspace via bpf_perf_event_output(); we - * // can use res (the string length) as event - * // size, after checking its boundaries. - * } - * - * In comparison, using **bpf_probe_read()** helper here instead - * to read the string would require to estimate the length at - * compile time, and would often result in copying more memory - * than necessary. - * - * Another useful use case is when parsing individual process - * arguments or individual environment variables navigating - * *current*\ **->mm->arg_start** and *current*\ - * **->mm->env_start**: using this helper and the return value, - * one can quickly iterate at the right offset of the memory area. - * Return - * On success, the strictly positive length of the string, - * including the trailing NUL character. On error, a negative - * value. - * - * u64 bpf_get_socket_cookie(struct sk_buff *skb) - * Description - * If the **struct sk_buff** pointed by *skb* has a known socket, - * retrieve the cookie (generated by the kernel) of this socket. - * If no cookie has been set yet, generate a new cookie. Once - * generated, the socket cookie remains stable for the life of the - * socket. This helper can be useful for monitoring per socket - * networking traffic statistics as it provides a unique socket - * identifier per namespace. - * Return - * A 8-byte long non-decreasing number on success, or 0 if the - * socket field is missing inside *skb*. - * - * u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx) - * Description - * Equivalent to bpf_get_socket_cookie() helper that accepts - * *skb*, but gets socket from **struct bpf_sock_addr** context. - * Return - * A 8-byte long non-decreasing number. - * - * u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx) - * Description - * Equivalent to bpf_get_socket_cookie() helper that accepts - * *skb*, but gets socket from **struct bpf_sock_ops** context. - * Return - * A 8-byte long non-decreasing number. - * - * u32 bpf_get_socket_uid(struct sk_buff *skb) - * Return - * The owner UID of the socket associated to *skb*. If the socket - * is **NULL**, or if it is not a full socket (i.e. if it is a - * time-wait or a request socket instead), **overflowuid** value - * is returned (note that **overflowuid** might also be the actual - * UID value for the socket). - * - * u32 bpf_set_hash(struct sk_buff *skb, u32 hash) - * Description - * Set the full hash for *skb* (set the field *skb*\ **->hash**) - * to value *hash*. - * Return - * 0 - * - * int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen) - * Description - * Emulate a call to **setsockopt()** on the socket associated to - * *bpf_socket*, which must be a full socket. The *level* at - * which the option resides and the name *optname* of the option - * must be specified, see **setsockopt(2)** for more information. - * The option value of length *optlen* is pointed by *optval*. - * - * This helper actually implements a subset of **setsockopt()**. - * It supports the following *level*\ s: - * - * * **SOL_SOCKET**, which supports the following *optname*\ s: - * **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**, - * **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**. - * * **IPPROTO_TCP**, which supports the following *optname*\ s: - * **TCP_CONGESTION**, **TCP_BPF_IW**, - * **TCP_BPF_SNDCWND_CLAMP**. - * * **IPPROTO_IP**, which supports *optname* **IP_TOS**. - * * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_adjust_room(struct sk_buff *skb, s32 len_diff, u32 mode, u64 flags) - * Description - * Grow or shrink the room for data in the packet associated to - * *skb* by *len_diff*, and according to the selected *mode*. - * - * There are two supported modes at this time: - * - * * **BPF_ADJ_ROOM_MAC**: Adjust room at the mac layer - * (room space is added or removed below the layer 2 header). - * - * * **BPF_ADJ_ROOM_NET**: Adjust room at the network layer - * (room space is added or removed below the layer 3 header). - * - * The following flags are supported at this time: - * - * * **BPF_F_ADJ_ROOM_FIXED_GSO**: Do not adjust gso_size. - * Adjusting mss in this way is not allowed for datagrams. - * - * * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 **: - * * **BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 **: - * Any new space is reserved to hold a tunnel header. - * Configure skb offsets and other fields accordingly. - * - * * **BPF_F_ADJ_ROOM_ENCAP_L4_GRE **: - * * **BPF_F_ADJ_ROOM_ENCAP_L4_UDP **: - * Use with ENCAP_L3 flags to further specify the tunnel type. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_redirect_map(struct bpf_map *map, u32 key, u64 flags) - * Description - * Redirect the packet to the endpoint referenced by *map* at - * index *key*. Depending on its type, this *map* can contain - * references to net devices (for forwarding packets through other - * ports), or to CPUs (for redirecting XDP frames to another CPU; - * but this is only implemented for native XDP (with driver - * support) as of this writing). - * - * All values for *flags* are reserved for future usage, and must - * be left at zero. - * - * When used to redirect packets to net devices, this helper - * provides a high performance increase over **bpf_redirect**\ (). - * This is due to various implementation details of the underlying - * mechanisms, one of which is the fact that **bpf_redirect_map**\ - * () tries to send packet as a "bulk" to the device. - * Return - * **XDP_REDIRECT** on success, or **XDP_ABORTED** on error. - * - * int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags) - * Description - * Redirect the packet to the socket referenced by *map* (of type - * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and - * egress interfaces can be used for redirection. The - * **BPF_F_INGRESS** value in *flags* is used to make the - * distinction (ingress path is selected if the flag is present, - * egress path otherwise). This is the only flag supported for now. - * Return - * **SK_PASS** on success, or **SK_DROP** on error. - * - * int bpf_sock_map_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags) - * Description - * Add an entry to, or update a *map* referencing sockets. The - * *skops* is used as a new value for the entry associated to - * *key*. *flags* is one of: - * - * **BPF_NOEXIST** - * The entry for *key* must not exist in the map. - * **BPF_EXIST** - * The entry for *key* must already exist in the map. - * **BPF_ANY** - * No condition on the existence of the entry for *key*. - * - * If the *map* has eBPF programs (parser and verdict), those will - * be inherited by the socket being added. If the socket is - * already attached to eBPF programs, this results in an error. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_xdp_adjust_meta(struct xdp_buff *xdp_md, int delta) - * Description - * Adjust the address pointed by *xdp_md*\ **->data_meta** by - * *delta* (which can be positive or negative). Note that this - * operation modifies the address stored in *xdp_md*\ **->data**, - * so the latter must be loaded only after the helper has been - * called. - * - * The use of *xdp_md*\ **->data_meta** is optional and programs - * are not required to use it. The rationale is that when the - * packet is processed with XDP (e.g. as DoS filter), it is - * possible to push further meta data along with it before passing - * to the stack, and to give the guarantee that an ingress eBPF - * program attached as a TC classifier on the same device can pick - * this up for further post-processing. Since TC works with socket - * buffers, it remains possible to set from XDP the **mark** or - * **priority** pointers, or other pointers for the socket buffer. - * Having this scratch space generic and programmable allows for - * more flexibility as the user is free to store whatever meta - * data they need. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_perf_event_read_value(struct bpf_map *map, u64 flags, struct bpf_perf_event_value *buf, u32 buf_size) - * Description - * Read the value of a perf event counter, and store it into *buf* - * of size *buf_size*. This helper relies on a *map* of type - * **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of the perf event - * counter is selected when *map* is updated with perf event file - * descriptors. The *map* is an array whose size is the number of - * available CPUs, and each cell contains a value relative to one - * CPU. The value to retrieve is indicated by *flags*, that - * contains the index of the CPU to look up, masked with - * **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to - * **BPF_F_CURRENT_CPU** to indicate that the value for the - * current CPU should be retrieved. - * - * This helper behaves in a way close to - * **bpf_perf_event_read**\ () helper, save that instead of - * just returning the value observed, it fills the *buf* - * structure. This allows for additional data to be retrieved: in - * particular, the enabled and running times (in *buf*\ - * **->enabled** and *buf*\ **->running**, respectively) are - * copied. In general, **bpf_perf_event_read_value**\ () is - * recommended over **bpf_perf_event_read**\ (), which has some - * ABI issues and provides fewer functionalities. - * - * These values are interesting, because hardware PMU (Performance - * Monitoring Unit) counters are limited resources. When there are - * more PMU based perf events opened than available counters, - * kernel will multiplex these events so each event gets certain - * percentage (but not all) of the PMU time. In case that - * multiplexing happens, the number of samples or counter value - * will not reflect the case compared to when no multiplexing - * occurs. This makes comparison between different runs difficult. - * Typically, the counter value should be normalized before - * comparing to other experiments. The usual normalization is done - * as follows. - * - * :: - * - * normalized_counter = counter * t_enabled / t_running - * - * Where t_enabled is the time enabled for event and t_running is - * the time running for event since last normalization. The - * enabled and running times are accumulated since the perf event - * open. To achieve scaling factor between two invocations of an - * eBPF program, users can can use CPU id as the key (which is - * typical for perf array usage model) to remember the previous - * value and do the calculation inside the eBPF program. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_perf_prog_read_value(struct bpf_perf_event_data *ctx, struct bpf_perf_event_value *buf, u32 buf_size) - * Description - * For en eBPF program attached to a perf event, retrieve the - * value of the event counter associated to *ctx* and store it in - * the structure pointed by *buf* and of size *buf_size*. Enabled - * and running times are also stored in the structure (see - * description of helper **bpf_perf_event_read_value**\ () for - * more details). - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen) - * Description - * Emulate a call to **getsockopt()** on the socket associated to - * *bpf_socket*, which must be a full socket. The *level* at - * which the option resides and the name *optname* of the option - * must be specified, see **getsockopt(2)** for more information. - * The retrieved value is stored in the structure pointed by - * *opval* and of length *optlen*. - * - * This helper actually implements a subset of **getsockopt()**. - * It supports the following *level*\ s: - * - * * **IPPROTO_TCP**, which supports *optname* - * **TCP_CONGESTION**. - * * **IPPROTO_IP**, which supports *optname* **IP_TOS**. - * * **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_override_return(struct pt_reg *regs, u64 rc) - * Description - * Used for error injection, this helper uses kprobes to override - * the return value of the probed function, and to set it to *rc*. - * The first argument is the context *regs* on which the kprobe - * works. - * - * This helper works by setting setting the PC (program counter) - * to an override function which is run in place of the original - * probed function. This means the probed function is not run at - * all. The replacement function just returns with the required - * value. - * - * This helper has security implications, and thus is subject to - * restrictions. It is only available if the kernel was compiled - * with the **CONFIG_BPF_KPROBE_OVERRIDE** configuration - * option, and in this case it only works on functions tagged with - * **ALLOW_ERROR_INJECTION** in the kernel code. - * - * Also, the helper is only available for the architectures having - * the CONFIG_FUNCTION_ERROR_INJECTION option. As of this writing, - * x86 architecture is the only one to support this feature. - * Return - * 0 - * - * int bpf_sock_ops_cb_flags_set(struct bpf_sock_ops *bpf_sock, int argval) - * Description - * Attempt to set the value of the **bpf_sock_ops_cb_flags** field - * for the full TCP socket associated to *bpf_sock_ops* to - * *argval*. - * - * The primary use of this field is to determine if there should - * be calls to eBPF programs of type - * **BPF_PROG_TYPE_SOCK_OPS** at various points in the TCP - * code. A program of the same type can change its value, per - * connection and as necessary, when the connection is - * established. This field is directly accessible for reading, but - * this helper must be used for updates in order to return an - * error if an eBPF program tries to set a callback that is not - * supported in the current kernel. - * - * The supported callback values that *argval* can combine are: - * - * * **BPF_SOCK_OPS_RTO_CB_FLAG** (retransmission time out) - * * **BPF_SOCK_OPS_RETRANS_CB_FLAG** (retransmission) - * * **BPF_SOCK_OPS_STATE_CB_FLAG** (TCP state change) - * - * Here are some examples of where one could call such eBPF - * program: - * - * * When RTO fires. - * * When a packet is retransmitted. - * * When the connection terminates. - * * When a packet is sent. - * * When a packet is received. - * Return - * Code **-EINVAL** if the socket is not a full TCP socket; - * otherwise, a positive number containing the bits that could not - * be set is returned (which comes down to 0 if all bits were set - * as required). - * - * int bpf_msg_redirect_map(struct sk_msg_buff *msg, struct bpf_map *map, u32 key, u64 flags) - * Description - * This helper is used in programs implementing policies at the - * socket level. If the message *msg* is allowed to pass (i.e. if - * the verdict eBPF program returns **SK_PASS**), redirect it to - * the socket referenced by *map* (of type - * **BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and - * egress interfaces can be used for redirection. The - * **BPF_F_INGRESS** value in *flags* is used to make the - * distinction (ingress path is selected if the flag is present, - * egress path otherwise). This is the only flag supported for now. - * Return - * **SK_PASS** on success, or **SK_DROP** on error. - * - * int bpf_msg_apply_bytes(struct sk_msg_buff *msg, u32 bytes) - * Description - * For socket policies, apply the verdict of the eBPF program to - * the next *bytes* (number of bytes) of message *msg*. - * - * For example, this helper can be used in the following cases: - * - * * A single **sendmsg**\ () or **sendfile**\ () system call - * contains multiple logical messages that the eBPF program is - * supposed to read and for which it should apply a verdict. - * * An eBPF program only cares to read the first *bytes* of a - * *msg*. If the message has a large payload, then setting up - * and calling the eBPF program repeatedly for all bytes, even - * though the verdict is already known, would create unnecessary - * overhead. - * - * When called from within an eBPF program, the helper sets a - * counter internal to the BPF infrastructure, that is used to - * apply the last verdict to the next *bytes*. If *bytes* is - * smaller than the current data being processed from a - * **sendmsg**\ () or **sendfile**\ () system call, the first - * *bytes* will be sent and the eBPF program will be re-run with - * the pointer for start of data pointing to byte number *bytes* - * **+ 1**. If *bytes* is larger than the current data being - * processed, then the eBPF verdict will be applied to multiple - * **sendmsg**\ () or **sendfile**\ () calls until *bytes* are - * consumed. - * - * Note that if a socket closes with the internal counter holding - * a non-zero value, this is not a problem because data is not - * being buffered for *bytes* and is sent as it is received. - * Return - * 0 - * - * int bpf_msg_cork_bytes(struct sk_msg_buff *msg, u32 bytes) - * Description - * For socket policies, prevent the execution of the verdict eBPF - * program for message *msg* until *bytes* (byte number) have been - * accumulated. - * - * This can be used when one needs a specific number of bytes - * before a verdict can be assigned, even if the data spans - * multiple **sendmsg**\ () or **sendfile**\ () calls. The extreme - * case would be a user calling **sendmsg**\ () repeatedly with - * 1-byte long message segments. Obviously, this is bad for - * performance, but it is still valid. If the eBPF program needs - * *bytes* bytes to validate a header, this helper can be used to - * prevent the eBPF program to be called again until *bytes* have - * been accumulated. - * Return - * 0 - * - * int bpf_msg_pull_data(struct sk_msg_buff *msg, u32 start, u32 end, u64 flags) - * Description - * For socket policies, pull in non-linear data from user space - * for *msg* and set pointers *msg*\ **->data** and *msg*\ - * **->data_end** to *start* and *end* bytes offsets into *msg*, - * respectively. - * - * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a - * *msg* it can only parse data that the (**data**, **data_end**) - * pointers have already consumed. For **sendmsg**\ () hooks this - * is likely the first scatterlist element. But for calls relying - * on the **sendpage** handler (e.g. **sendfile**\ ()) this will - * be the range (**0**, **0**) because the data is shared with - * user space and by default the objective is to avoid allowing - * user space to modify data while (or after) eBPF verdict is - * being decided. This helper can be used to pull in data and to - * set the start and end pointer to given values. Data will be - * copied if necessary (i.e. if data was not linear and if start - * and end pointers do not point to the same chunk). - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * - * All values for *flags* are reserved for future usage, and must - * be left at zero. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_bind(struct bpf_sock_addr *ctx, struct sockaddr *addr, int addr_len) - * Description - * Bind the socket associated to *ctx* to the address pointed by - * *addr*, of length *addr_len*. This allows for making outgoing - * connection from the desired IP address, which can be useful for - * example when all processes inside a cgroup should use one - * single IP address on a host that has multiple IP configured. - * - * This helper works for IPv4 and IPv6, TCP and UDP sockets. The - * domain (*addr*\ **->sa_family**) must be **AF_INET** (or - * **AF_INET6**). Looking for a free port to bind to can be - * expensive, therefore binding to port is not permitted by the - * helper: *addr*\ **->sin_port** (or **sin6_port**, respectively) - * must be set to zero. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_xdp_adjust_tail(struct xdp_buff *xdp_md, int delta) - * Description - * Adjust (move) *xdp_md*\ **->data_end** by *delta* bytes. It is - * only possible to shrink the packet as of this writing, - * therefore *delta* must be a negative integer. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_skb_get_xfrm_state(struct sk_buff *skb, u32 index, struct bpf_xfrm_state *xfrm_state, u32 size, u64 flags) - * Description - * Retrieve the XFRM state (IP transform framework, see also - * **ip-xfrm(8)**) at *index* in XFRM "security path" for *skb*. - * - * The retrieved value is stored in the **struct bpf_xfrm_state** - * pointed by *xfrm_state* and of length *size*. - * - * All values for *flags* are reserved for future usage, and must - * be left at zero. - * - * This helper is available only if the kernel was compiled with - * **CONFIG_XFRM** configuration option. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_get_stack(struct pt_regs *regs, void *buf, u32 size, u64 flags) - * Description - * Return a user or a kernel stack in bpf program provided buffer. - * To achieve this, the helper needs *ctx*, which is a pointer - * to the context on which the tracing program is executed. - * To store the stacktrace, the bpf program provides *buf* with - * a nonnegative *size*. - * - * The last argument, *flags*, holds the number of stack frames to - * skip (from 0 to 255), masked with - * **BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set - * the following flags: - * - * **BPF_F_USER_STACK** - * Collect a user space stack instead of a kernel stack. - * **BPF_F_USER_BUILD_ID** - * Collect buildid+offset instead of ips for user stack, - * only valid if **BPF_F_USER_STACK** is also specified. - * - * **bpf_get_stack**\ () can collect up to - * **PERF_MAX_STACK_DEPTH** both kernel and user frames, subject - * to sufficient large buffer size. Note that - * this limit can be controlled with the **sysctl** program, and - * that it should be manually increased in order to profile long - * user stacks (such as stacks for Java programs). To do so, use: - * - * :: - * - * # sysctl kernel.perf_event_max_stack=<new value> - * Return - * A non-negative value equal to or less than *size* on success, - * or a negative error in case of failure. - * - * int bpf_skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header) - * Description - * This helper is similar to **bpf_skb_load_bytes**\ () in that - * it provides an easy way to load *len* bytes from *offset* - * from the packet associated to *skb*, into the buffer pointed - * by *to*. The difference to **bpf_skb_load_bytes**\ () is that - * a fifth argument *start_header* exists in order to select a - * base offset to start from. *start_header* can be one of: - * - * **BPF_HDR_START_MAC** - * Base offset to load data from is *skb*'s mac header. - * **BPF_HDR_START_NET** - * Base offset to load data from is *skb*'s network header. - * - * In general, "direct packet access" is the preferred method to - * access packet data, however, this helper is in particular useful - * in socket filters where *skb*\ **->data** does not always point - * to the start of the mac header and where "direct packet access" - * is not available. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_fib_lookup(void *ctx, struct bpf_fib_lookup *params, int plen, u32 flags) - * Description - * Do FIB lookup in kernel tables using parameters in *params*. - * If lookup is successful and result shows packet is to be - * forwarded, the neighbor tables are searched for the nexthop. - * If successful (ie., FIB lookup shows forwarding and nexthop - * is resolved), the nexthop address is returned in ipv4_dst - * or ipv6_dst based on family, smac is set to mac address of - * egress device, dmac is set to nexthop mac address, rt_metric - * is set to metric from route (IPv4/IPv6 only), and ifindex - * is set to the device index of the nexthop from the FIB lookup. - * - * *plen* argument is the size of the passed in struct. - * *flags* argument can be a combination of one or more of the - * following values: - * - * **BPF_FIB_LOOKUP_DIRECT** - * Do a direct table lookup vs full lookup using FIB - * rules. - * **BPF_FIB_LOOKUP_OUTPUT** - * Perform lookup from an egress perspective (default is - * ingress). - * - * *ctx* is either **struct xdp_md** for XDP programs or - * **struct sk_buff** tc cls_act programs. - * Return - * * < 0 if any input argument is invalid - * * 0 on success (packet is forwarded, nexthop neighbor exists) - * * > 0 one of **BPF_FIB_LKUP_RET_** codes explaining why the - * packet is not forwarded or needs assist from full stack - * - * int bpf_sock_hash_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags) - * Description - * Add an entry to, or update a sockhash *map* referencing sockets. - * The *skops* is used as a new value for the entry associated to - * *key*. *flags* is one of: - * - * **BPF_NOEXIST** - * The entry for *key* must not exist in the map. - * **BPF_EXIST** - * The entry for *key* must already exist in the map. - * **BPF_ANY** - * No condition on the existence of the entry for *key*. - * - * If the *map* has eBPF programs (parser and verdict), those will - * be inherited by the socket being added. If the socket is - * already attached to eBPF programs, this results in an error. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_msg_redirect_hash(struct sk_msg_buff *msg, struct bpf_map *map, void *key, u64 flags) - * Description - * This helper is used in programs implementing policies at the - * socket level. If the message *msg* is allowed to pass (i.e. if - * the verdict eBPF program returns **SK_PASS**), redirect it to - * the socket referenced by *map* (of type - * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and - * egress interfaces can be used for redirection. The - * **BPF_F_INGRESS** value in *flags* is used to make the - * distinction (ingress path is selected if the flag is present, - * egress path otherwise). This is the only flag supported for now. - * Return - * **SK_PASS** on success, or **SK_DROP** on error. - * - * int bpf_sk_redirect_hash(struct sk_buff *skb, struct bpf_map *map, void *key, u64 flags) - * Description - * This helper is used in programs implementing policies at the - * skb socket level. If the sk_buff *skb* is allowed to pass (i.e. - * if the verdeict eBPF program returns **SK_PASS**), redirect it - * to the socket referenced by *map* (of type - * **BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and - * egress interfaces can be used for redirection. The - * **BPF_F_INGRESS** value in *flags* is used to make the - * distinction (ingress path is selected if the flag is present, - * egress otherwise). This is the only flag supported for now. - * Return - * **SK_PASS** on success, or **SK_DROP** on error. - * - * int bpf_lwt_push_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len) - * Description - * Encapsulate the packet associated to *skb* within a Layer 3 - * protocol header. This header is provided in the buffer at - * address *hdr*, with *len* its size in bytes. *type* indicates - * the protocol of the header and can be one of: - * - * **BPF_LWT_ENCAP_SEG6** - * IPv6 encapsulation with Segment Routing Header - * (**struct ipv6_sr_hdr**). *hdr* only contains the SRH, - * the IPv6 header is computed by the kernel. - * **BPF_LWT_ENCAP_SEG6_INLINE** - * Only works if *skb* contains an IPv6 packet. Insert a - * Segment Routing Header (**struct ipv6_sr_hdr**) inside - * the IPv6 header. - * **BPF_LWT_ENCAP_IP** - * IP encapsulation (GRE/GUE/IPIP/etc). The outer header - * must be IPv4 or IPv6, followed by zero or more - * additional headers, up to LWT_BPF_MAX_HEADROOM total - * bytes in all prepended headers. Please note that - * if skb_is_gso(skb) is true, no more than two headers - * can be prepended, and the inner header, if present, - * should be either GRE or UDP/GUE. - * - * BPF_LWT_ENCAP_SEG6*** types can be called by bpf programs of - * type BPF_PROG_TYPE_LWT_IN; BPF_LWT_ENCAP_IP type can be called - * by bpf programs of types BPF_PROG_TYPE_LWT_IN and - * BPF_PROG_TYPE_LWT_XMIT. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_lwt_seg6_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len) - * Description - * Store *len* bytes from address *from* into the packet - * associated to *skb*, at *offset*. Only the flags, tag and TLVs - * inside the outermost IPv6 Segment Routing Header can be - * modified through this helper. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_lwt_seg6_adjust_srh(struct sk_buff *skb, u32 offset, s32 delta) - * Description - * Adjust the size allocated to TLVs in the outermost IPv6 - * Segment Routing Header contained in the packet associated to - * *skb*, at position *offset* by *delta* bytes. Only offsets - * after the segments are accepted. *delta* can be as well - * positive (growing) as negative (shrinking). - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_lwt_seg6_action(struct sk_buff *skb, u32 action, void *param, u32 param_len) - * Description - * Apply an IPv6 Segment Routing action of type *action* to the - * packet associated to *skb*. Each action takes a parameter - * contained at address *param*, and of length *param_len* bytes. - * *action* can be one of: - * - * **SEG6_LOCAL_ACTION_END_X** - * End.X action: Endpoint with Layer-3 cross-connect. - * Type of *param*: **struct in6_addr**. - * **SEG6_LOCAL_ACTION_END_T** - * End.T action: Endpoint with specific IPv6 table lookup. - * Type of *param*: **int**. - * **SEG6_LOCAL_ACTION_END_B6** - * End.B6 action: Endpoint bound to an SRv6 policy. - * Type of param: **struct ipv6_sr_hdr**. - * **SEG6_LOCAL_ACTION_END_B6_ENCAP** - * End.B6.Encap action: Endpoint bound to an SRv6 - * encapsulation policy. - * Type of param: **struct ipv6_sr_hdr**. - * - * A call to this helper is susceptible to change the underlaying - * packet buffer. Therefore, at load time, all checks on pointers - * previously done by the verifier are invalidated and must be - * performed again, if the helper is used in combination with - * direct packet access. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_rc_repeat(void *ctx) - * Description - * This helper is used in programs implementing IR decoding, to - * report a successfully decoded repeat key message. This delays - * the generation of a key up event for previously generated - * key down event. - * - * Some IR protocols like NEC have a special IR message for - * repeating last button, for when a button is held down. - * - * The *ctx* should point to the lirc sample as passed into - * the program. - * - * This helper is only available is the kernel was compiled with - * the **CONFIG_BPF_LIRC_MODE2** configuration option set to - * "**y**". - * Return - * 0 - * - * int bpf_rc_keydown(void *ctx, u32 protocol, u64 scancode, u32 toggle) - * Description - * This helper is used in programs implementing IR decoding, to - * report a successfully decoded key press with *scancode*, - * *toggle* value in the given *protocol*. The scancode will be - * translated to a keycode using the rc keymap, and reported as - * an input key down event. After a period a key up event is - * generated. This period can be extended by calling either - * **bpf_rc_keydown**\ () again with the same values, or calling - * **bpf_rc_repeat**\ (). - * - * Some protocols include a toggle bit, in case the button was - * released and pressed again between consecutive scancodes. - * - * The *ctx* should point to the lirc sample as passed into - * the program. - * - * The *protocol* is the decoded protocol number (see - * **enum rc_proto** for some predefined values). - * - * This helper is only available is the kernel was compiled with - * the **CONFIG_BPF_LIRC_MODE2** configuration option set to - * "**y**". - * Return - * 0 - * - * u64 bpf_skb_cgroup_id(struct sk_buff *skb) - * Description - * Return the cgroup v2 id of the socket associated with the *skb*. - * This is roughly similar to the **bpf_get_cgroup_classid**\ () - * helper for cgroup v1 by providing a tag resp. identifier that - * can be matched on or used for map lookups e.g. to implement - * policy. The cgroup v2 id of a given path in the hierarchy is - * exposed in user space through the f_handle API in order to get - * to the same 64-bit id. - * - * This helper can be used on TC egress path, but not on ingress, - * and is available only if the kernel was compiled with the - * **CONFIG_SOCK_CGROUP_DATA** configuration option. - * Return - * The id is returned or 0 in case the id could not be retrieved. - * - * u64 bpf_get_current_cgroup_id(void) - * Return - * A 64-bit integer containing the current cgroup id based - * on the cgroup within which the current task is running. - * - * void *bpf_get_local_storage(void *map, u64 flags) - * Description - * Get the pointer to the local storage area. - * The type and the size of the local storage is defined - * by the *map* argument. - * The *flags* meaning is specific for each map type, - * and has to be 0 for cgroup local storage. - * - * Depending on the BPF program type, a local storage area - * can be shared between multiple instances of the BPF program, - * running simultaneously. - * - * A user should care about the synchronization by himself. - * For example, by using the **BPF_STX_XADD** instruction to alter - * the shared data. - * Return - * A pointer to the local storage area. - * - * int bpf_sk_select_reuseport(struct sk_reuseport_md *reuse, struct bpf_map *map, void *key, u64 flags) - * Description - * Select a **SO_REUSEPORT** socket from a - * **BPF_MAP_TYPE_REUSEPORT_ARRAY** *map*. - * It checks the selected socket is matching the incoming - * request in the socket buffer. - * Return - * 0 on success, or a negative error in case of failure. - * - * u64 bpf_skb_ancestor_cgroup_id(struct sk_buff *skb, int ancestor_level) - * Description - * Return id of cgroup v2 that is ancestor of cgroup associated - * with the *skb* at the *ancestor_level*. The root cgroup is at - * *ancestor_level* zero and each step down the hierarchy - * increments the level. If *ancestor_level* == level of cgroup - * associated with *skb*, then return value will be same as that - * of **bpf_skb_cgroup_id**\ (). - * - * The helper is useful to implement policies based on cgroups - * that are upper in hierarchy than immediate cgroup associated - * with *skb*. - * - * The format of returned id and helper limitations are same as in - * **bpf_skb_cgroup_id**\ (). - * Return - * The id is returned or 0 in case the id could not be retrieved. - * - * struct bpf_sock *bpf_sk_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags) - * Description - * Look for TCP socket matching *tuple*, optionally in a child - * network namespace *netns*. The return value must be checked, - * and if non-**NULL**, released via **bpf_sk_release**\ (). - * - * The *ctx* should point to the context of the program, such as - * the skb or socket (depending on the hook in use). This is used - * to determine the base network namespace for the lookup. - * - * *tuple_size* must be one of: - * - * **sizeof**\ (*tuple*\ **->ipv4**) - * Look for an IPv4 socket. - * **sizeof**\ (*tuple*\ **->ipv6**) - * Look for an IPv6 socket. - * - * If the *netns* is a negative signed 32-bit integer, then the - * socket lookup table in the netns associated with the *ctx* will - * will be used. For the TC hooks, this is the netns of the device - * in the skb. For socket hooks, this is the netns of the socket. - * If *netns* is any other signed 32-bit value greater than or - * equal to zero then it specifies the ID of the netns relative to - * the netns associated with the *ctx*. *netns* values beyond the - * range of 32-bit integers are reserved for future use. - * - * All values for *flags* are reserved for future usage, and must - * be left at zero. - * - * This helper is available only if the kernel was compiled with - * **CONFIG_NET** configuration option. - * Return - * Pointer to **struct bpf_sock**, or **NULL** in case of failure. - * For sockets with reuseport option, the **struct bpf_sock** - * result is from **reuse->socks**\ [] using the hash of the tuple. - * - * struct bpf_sock *bpf_sk_lookup_udp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags) - * Description - * Look for UDP socket matching *tuple*, optionally in a child - * network namespace *netns*. The return value must be checked, - * and if non-**NULL**, released via **bpf_sk_release**\ (). - * - * The *ctx* should point to the context of the program, such as - * the skb or socket (depending on the hook in use). This is used - * to determine the base network namespace for the lookup. - * - * *tuple_size* must be one of: - * - * **sizeof**\ (*tuple*\ **->ipv4**) - * Look for an IPv4 socket. - * **sizeof**\ (*tuple*\ **->ipv6**) - * Look for an IPv6 socket. - * - * If the *netns* is a negative signed 32-bit integer, then the - * socket lookup table in the netns associated with the *ctx* will - * will be used. For the TC hooks, this is the netns of the device - * in the skb. For socket hooks, this is the netns of the socket. - * If *netns* is any other signed 32-bit value greater than or - * equal to zero then it specifies the ID of the netns relative to - * the netns associated with the *ctx*. *netns* values beyond the - * range of 32-bit integers are reserved for future use. - * - * All values for *flags* are reserved for future usage, and must - * be left at zero. - * - * This helper is available only if the kernel was compiled with - * **CONFIG_NET** configuration option. - * Return - * Pointer to **struct bpf_sock**, or **NULL** in case of failure. - * For sockets with reuseport option, the **struct bpf_sock** - * result is from **reuse->socks**\ [] using the hash of the tuple. - * - * int bpf_sk_release(struct bpf_sock *sock) - * Description - * Release the reference held by *sock*. *sock* must be a - * non-**NULL** pointer that was returned from - * **bpf_sk_lookup_xxx**\ (). - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_map_push_elem(struct bpf_map *map, const void *value, u64 flags) - * Description - * Push an element *value* in *map*. *flags* is one of: - * - * **BPF_EXIST** - * If the queue/stack is full, the oldest element is - * removed to make room for this. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_map_pop_elem(struct bpf_map *map, void *value) - * Description - * Pop an element from *map*. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_map_peek_elem(struct bpf_map *map, void *value) - * Description - * Get an element from *map* without removing it. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_msg_push_data(struct sk_buff *skb, u32 start, u32 len, u64 flags) - * Description - * For socket policies, insert *len* bytes into *msg* at offset - * *start*. - * - * If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a - * *msg* it may want to insert metadata or options into the *msg*. - * This can later be read and used by any of the lower layer BPF - * hooks. - * - * This helper may fail if under memory pressure (a malloc - * fails) in these cases BPF programs will get an appropriate - * error and BPF programs will need to handle them. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_msg_pop_data(struct sk_msg_buff *msg, u32 start, u32 pop, u64 flags) - * Description - * Will remove *pop* bytes from a *msg* starting at byte *start*. - * This may result in **ENOMEM** errors under certain situations if - * an allocation and copy are required due to a full ring buffer. - * However, the helper will try to avoid doing the allocation - * if possible. Other errors can occur if input parameters are - * invalid either due to *start* byte not being valid part of *msg* - * payload and/or *pop* value being to large. - * Return - * 0 on success, or a negative error in case of failure. - * - * int bpf_rc_pointer_rel(void *ctx, s32 rel_x, s32 rel_y) - * Description - * This helper is used in programs implementing IR decoding, to - * report a successfully decoded pointer movement. - * - * The *ctx* should point to the lirc sample as passed into - * the program. - * - * This helper is only available is the kernel was compiled with - * the **CONFIG_BPF_LIRC_MODE2** configuration option set to - * "**y**". - * Return - * 0 - * - * int bpf_spin_lock(struct bpf_spin_lock *lock) - * Description - * Acquire a spinlock represented by the pointer *lock*, which is - * stored as part of a value of a map. Taking the lock allows to - * safely update the rest of the fields in that value. The - * spinlock can (and must) later be released with a call to - * **bpf_spin_unlock**\ (\ *lock*\ ). - * - * Spinlocks in BPF programs come with a number of restrictions - * and constraints: - * - * * **bpf_spin_lock** objects are only allowed inside maps of - * types **BPF_MAP_TYPE_HASH** and **BPF_MAP_TYPE_ARRAY** (this - * list could be extended in the future). - * * BTF description of the map is mandatory. - * * The BPF program can take ONE lock at a time, since taking two - * or more could cause dead locks. - * * Only one **struct bpf_spin_lock** is allowed per map element. - * * When the lock is taken, calls (either BPF to BPF or helpers) - * are not allowed. - * * The **BPF_LD_ABS** and **BPF_LD_IND** instructions are not - * allowed inside a spinlock-ed region. - * * The BPF program MUST call **bpf_spin_unlock**\ () to release - * the lock, on all execution paths, before it returns. - * * The BPF program can access **struct bpf_spin_lock** only via - * the **bpf_spin_lock**\ () and **bpf_spin_unlock**\ () - * helpers. Loading or storing data into the **struct - * bpf_spin_lock** *lock*\ **;** field of a map is not allowed. - * * To use the **bpf_spin_lock**\ () helper, the BTF description - * of the map value must be a struct and have **struct - * bpf_spin_lock** *anyname*\ **;** field at the top level. - * Nested lock inside another struct is not allowed. - * * The **struct bpf_spin_lock** *lock* field in a map value must - * be aligned on a multiple of 4 bytes in that value. - * * Syscall with command **BPF_MAP_LOOKUP_ELEM** does not copy - * the **bpf_spin_lock** field to user space. - * * Syscall with command **BPF_MAP_UPDATE_ELEM**, or update from - * a BPF program, do not update the **bpf_spin_lock** field. - * * **bpf_spin_lock** cannot be on the stack or inside a - * networking packet (it can only be inside of a map values). - * * **bpf_spin_lock** is available to root only. - * * Tracing programs and socket filter programs cannot use - * **bpf_spin_lock**\ () due to insufficient preemption checks - * (but this may change in the future). - * * **bpf_spin_lock** is not allowed in inner maps of map-in-map. - * Return - * 0 - * - * int bpf_spin_unlock(struct bpf_spin_lock *lock) - * Description - * Release the *lock* previously locked by a call to - * **bpf_spin_lock**\ (\ *lock*\ ). - * Return - * 0 - * - * struct bpf_sock *bpf_sk_fullsock(struct bpf_sock *sk) - * Description - * This helper gets a **struct bpf_sock** pointer such - * that all the fields in this **bpf_sock** can be accessed. - * Return - * A **struct bpf_sock** pointer on success, or **NULL** in - * case of failure. - * - * struct bpf_tcp_sock *bpf_tcp_sock(struct bpf_sock *sk) - * Description - * This helper gets a **struct bpf_tcp_sock** pointer from a - * **struct bpf_sock** pointer. - * Return - * A **struct bpf_tcp_sock** pointer on success, or **NULL** in - * case of failure. - * - * int bpf_skb_ecn_set_ce(struct sk_buf *skb) - * Description - * Set ECN (Explicit Congestion Notification) field of IP header - * to **CE** (Congestion Encountered) if current value is **ECT** - * (ECN Capable Transport). Otherwise, do nothing. Works with IPv6 - * and IPv4. - * Return - * 1 if the **CE** flag is set (either by the current helper call - * or because it was already present), 0 if it is not set. - * - * struct bpf_sock *bpf_get_listener_sock(struct bpf_sock *sk) - * Description - * Return a **struct bpf_sock** pointer in **TCP_LISTEN** state. - * **bpf_sk_release**\ () is unnecessary and not allowed. - * Return - * A **struct bpf_sock** pointer on success, or **NULL** in - * case of failure. - * - * struct bpf_sock *bpf_skc_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags) - * Description - * Look for TCP socket matching *tuple*, optionally in a child - * network namespace *netns*. The return value must be checked, - * and if non-**NULL**, released via **bpf_sk_release**\ (). - * - * This function is identical to bpf_sk_lookup_tcp, except that it - * also returns timewait or request sockets. Use bpf_sk_fullsock - * or bpf_tcp_socket to access the full structure. - * - * This helper is available only if the kernel was compiled with - * **CONFIG_NET** configuration option. - * Return - * Pointer to **struct bpf_sock**, or **NULL** in case of failure. - * For sockets with reuseport option, the **struct bpf_sock** - * result is from **reuse->socks**\ [] using the hash of the tuple. - * - * int bpf_tcp_check_syncookie(struct bpf_sock *sk, void *iph, u32 iph_len, struct tcphdr *th, u32 th_len) - * Description - * Check whether iph and th contain a valid SYN cookie ACK for - * the listening socket in sk. - * - * iph points to the start of the IPv4 or IPv6 header, while - * iph_len contains sizeof(struct iphdr) or sizeof(struct ip6hdr). - * - * th points to the start of the TCP header, while th_len contains - * sizeof(struct tcphdr). - * - * Return - * 0 if iph and th are a valid SYN cookie ACK, or a negative error - * otherwise. - */ -#define __BPF_FUNC_MAPPER(FN) \ - FN(unspec), \ - FN(map_lookup_elem), \ - FN(map_update_elem), \ - FN(map_delete_elem), \ - FN(probe_read), \ - FN(ktime_get_ns), \ - FN(trace_printk), \ - FN(get_prandom_u32), \ - FN(get_smp_processor_id), \ - FN(skb_store_bytes), \ - FN(l3_csum_replace), \ - FN(l4_csum_replace), \ - FN(tail_call), \ - FN(clone_redirect), \ - FN(get_current_pid_tgid), \ - FN(get_current_uid_gid), \ - FN(get_current_comm), \ - FN(get_cgroup_classid), \ - FN(skb_vlan_push), \ - FN(skb_vlan_pop), \ - FN(skb_get_tunnel_key), \ - FN(skb_set_tunnel_key), \ - FN(perf_event_read), \ - FN(redirect), \ - FN(get_route_realm), \ - FN(perf_event_output), \ - FN(skb_load_bytes), \ - FN(get_stackid), \ - FN(csum_diff), \ - FN(skb_get_tunnel_opt), \ - FN(skb_set_tunnel_opt), \ - FN(skb_change_proto), \ - FN(skb_change_type), \ - FN(skb_under_cgroup), \ - FN(get_hash_recalc), \ - FN(get_current_task), \ - FN(probe_write_user), \ - FN(current_task_under_cgroup), \ - FN(skb_change_tail), \ - FN(skb_pull_data), \ - FN(csum_update), \ - FN(set_hash_invalid), \ - FN(get_numa_node_id), \ - FN(skb_change_head), \ - FN(xdp_adjust_head), \ - FN(probe_read_str), \ - FN(get_socket_cookie), \ - FN(get_socket_uid), \ - FN(set_hash), \ - FN(setsockopt), \ - FN(skb_adjust_room), \ - FN(redirect_map), \ - FN(sk_redirect_map), \ - FN(sock_map_update), \ - FN(xdp_adjust_meta), \ - FN(perf_event_read_value), \ - FN(perf_prog_read_value), \ - FN(getsockopt), \ - FN(override_return), \ - FN(sock_ops_cb_flags_set), \ - FN(msg_redirect_map), \ - FN(msg_apply_bytes), \ - FN(msg_cork_bytes), \ - FN(msg_pull_data), \ - FN(bind), \ - FN(xdp_adjust_tail), \ - FN(skb_get_xfrm_state), \ - FN(get_stack), \ - FN(skb_load_bytes_relative), \ - FN(fib_lookup), \ - FN(sock_hash_update), \ - FN(msg_redirect_hash), \ - FN(sk_redirect_hash), \ - FN(lwt_push_encap), \ - FN(lwt_seg6_store_bytes), \ - FN(lwt_seg6_adjust_srh), \ - FN(lwt_seg6_action), \ - FN(rc_repeat), \ - FN(rc_keydown), \ - FN(skb_cgroup_id), \ - FN(get_current_cgroup_id), \ - FN(get_local_storage), \ - FN(sk_select_reuseport), \ - FN(skb_ancestor_cgroup_id), \ - FN(sk_lookup_tcp), \ - FN(sk_lookup_udp), \ - FN(sk_release), \ - FN(map_push_elem), \ - FN(map_pop_elem), \ - FN(map_peek_elem), \ - FN(msg_push_data), \ - FN(msg_pop_data), \ - FN(rc_pointer_rel), \ - FN(spin_lock), \ - FN(spin_unlock), \ - FN(sk_fullsock), \ - FN(tcp_sock), \ - FN(skb_ecn_set_ce), \ - FN(get_listener_sock), \ - FN(skc_lookup_tcp), \ - FN(tcp_check_syncookie), - -/* integer value in 'imm' field of BPF_CALL instruction selects which helper - * function eBPF program intends to call - */ -#define __BPF_ENUM_FN(x) BPF_FUNC_ ## x -enum bpf_func_id { - __BPF_FUNC_MAPPER(__BPF_ENUM_FN) - __BPF_FUNC_MAX_ID, -}; -#undef __BPF_ENUM_FN - -/* All flags used by eBPF helper functions, placed here. */ - -/* BPF_FUNC_skb_store_bytes flags. */ -#define BPF_F_RECOMPUTE_CSUM (1ULL << 0) -#define BPF_F_INVALIDATE_HASH (1ULL << 1) - -/* BPF_FUNC_l3_csum_replace and BPF_FUNC_l4_csum_replace flags. - * First 4 bits are for passing the header field size. - */ -#define BPF_F_HDR_FIELD_MASK 0xfULL - -/* BPF_FUNC_l4_csum_replace flags. */ -#define BPF_F_PSEUDO_HDR (1ULL << 4) -#define BPF_F_MARK_MANGLED_0 (1ULL << 5) -#define BPF_F_MARK_ENFORCE (1ULL << 6) - -/* BPF_FUNC_clone_redirect and BPF_FUNC_redirect flags. */ -#define BPF_F_INGRESS (1ULL << 0) - -/* BPF_FUNC_skb_set_tunnel_key and BPF_FUNC_skb_get_tunnel_key flags. */ -#define BPF_F_TUNINFO_IPV6 (1ULL << 0) - -/* flags for both BPF_FUNC_get_stackid and BPF_FUNC_get_stack. */ -#define BPF_F_SKIP_FIELD_MASK 0xffULL -#define BPF_F_USER_STACK (1ULL << 8) -/* flags used by BPF_FUNC_get_stackid only. */ -#define BPF_F_FAST_STACK_CMP (1ULL << 9) -#define BPF_F_REUSE_STACKID (1ULL << 10) -/* flags used by BPF_FUNC_get_stack only. */ -#define BPF_F_USER_BUILD_ID (1ULL << 11) - -/* BPF_FUNC_skb_set_tunnel_key flags. */ -#define BPF_F_ZERO_CSUM_TX (1ULL << 1) -#define BPF_F_DONT_FRAGMENT (1ULL << 2) -#define BPF_F_SEQ_NUMBER (1ULL << 3) - -/* BPF_FUNC_perf_event_output, BPF_FUNC_perf_event_read and - * BPF_FUNC_perf_event_read_value flags. - */ -#define BPF_F_INDEX_MASK 0xffffffffULL -#define BPF_F_CURRENT_CPU BPF_F_INDEX_MASK -/* BPF_FUNC_perf_event_output for sk_buff input context. */ -#define BPF_F_CTXLEN_MASK (0xfffffULL << 32) - -/* Current network namespace */ -#define BPF_F_CURRENT_NETNS (-1L) - -/* BPF_FUNC_skb_adjust_room flags. */ -#define BPF_F_ADJ_ROOM_FIXED_GSO (1ULL << 0) - -#define BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 (1ULL << 1) -#define BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 (1ULL << 2) -#define BPF_F_ADJ_ROOM_ENCAP_L4_GRE (1ULL << 3) -#define BPF_F_ADJ_ROOM_ENCAP_L4_UDP (1ULL << 4) - -/* Mode for BPF_FUNC_skb_adjust_room helper. */ -enum bpf_adj_room_mode { - BPF_ADJ_ROOM_NET, - BPF_ADJ_ROOM_MAC, -}; - -/* Mode for BPF_FUNC_skb_load_bytes_relative helper. */ -enum bpf_hdr_start_off { - BPF_HDR_START_MAC, - BPF_HDR_START_NET, -}; - -/* Encapsulation type for BPF_FUNC_lwt_push_encap helper. */ -enum bpf_lwt_encap_mode { - BPF_LWT_ENCAP_SEG6, - BPF_LWT_ENCAP_SEG6_INLINE, - BPF_LWT_ENCAP_IP, -}; - -#define __bpf_md_ptr(type, name) \ -union { \ - type name; \ - __u64 :64; \ -} __attribute__((aligned(8))) - -/* user accessible mirror of in-kernel sk_buff. - * new fields can only be added to the end of this structure - */ -struct __sk_buff { - __u32 len; - __u32 pkt_type; - __u32 mark; - __u32 queue_mapping; - __u32 protocol; - __u32 vlan_present; - __u32 vlan_tci; - __u32 vlan_proto; - __u32 priority; - __u32 ingress_ifindex; - __u32 ifindex; - __u32 tc_index; - __u32 cb[5]; - __u32 hash; - __u32 tc_classid; - __u32 data; - __u32 data_end; - __u32 napi_id; - - /* Accessed by BPF_PROG_TYPE_sk_skb types from here to ... */ - __u32 family; - __u32 remote_ip4; /* Stored in network byte order */ - __u32 local_ip4; /* Stored in network byte order */ - __u32 remote_ip6[4]; /* Stored in network byte order */ - __u32 local_ip6[4]; /* Stored in network byte order */ - __u32 remote_port; /* Stored in network byte order */ - __u32 local_port; /* stored in host byte order */ - /* ... here. */ - - __u32 data_meta; - __bpf_md_ptr(struct bpf_flow_keys *, flow_keys); - __u64 tstamp; - __u32 wire_len; - __u32 gso_segs; - __bpf_md_ptr(struct bpf_sock *, sk); -}; - -struct bpf_tunnel_key { - __u32 tunnel_id; - union { - __u32 remote_ipv4; - __u32 remote_ipv6[4]; - }; - __u8 tunnel_tos; - __u8 tunnel_ttl; - __u16 tunnel_ext; /* Padding, future use. */ - __u32 tunnel_label; -}; - -/* user accessible mirror of in-kernel xfrm_state. - * new fields can only be added to the end of this structure - */ -struct bpf_xfrm_state { - __u32 reqid; - __u32 spi; /* Stored in network byte order */ - __u16 family; - __u16 ext; /* Padding, future use. */ - union { - __u32 remote_ipv4; /* Stored in network byte order */ - __u32 remote_ipv6[4]; /* Stored in network byte order */ - }; -}; - -/* Generic BPF return codes which all BPF program types may support. - * The values are binary compatible with their TC_ACT_* counter-part to - * provide backwards compatibility with existing SCHED_CLS and SCHED_ACT - * programs. - * - * XDP is handled seprately, see XDP_*. - */ -enum bpf_ret_code { - BPF_OK = 0, - /* 1 reserved */ - BPF_DROP = 2, - /* 3-6 reserved */ - BPF_REDIRECT = 7, - /* >127 are reserved for prog type specific return codes. - * - * BPF_LWT_REROUTE: used by BPF_PROG_TYPE_LWT_IN and - * BPF_PROG_TYPE_LWT_XMIT to indicate that skb had been - * changed and should be routed based on its new L3 header. - * (This is an L3 redirect, as opposed to L2 redirect - * represented by BPF_REDIRECT above). - */ - BPF_LWT_REROUTE = 128, -}; - -struct bpf_sock { - __u32 bound_dev_if; - __u32 family; - __u32 type; - __u32 protocol; - __u32 mark; - __u32 priority; - /* IP address also allows 1 and 2 bytes access */ - __u32 src_ip4; - __u32 src_ip6[4]; - __u32 src_port; /* host byte order */ - __u32 dst_port; /* network byte order */ - __u32 dst_ip4; - __u32 dst_ip6[4]; - __u32 state; -}; - -struct bpf_tcp_sock { - __u32 snd_cwnd; /* Sending congestion window */ - __u32 srtt_us; /* smoothed round trip time << 3 in usecs */ - __u32 rtt_min; - __u32 snd_ssthresh; /* Slow start size threshold */ - __u32 rcv_nxt; /* What we want to receive next */ - __u32 snd_nxt; /* Next sequence we send */ - __u32 snd_una; /* First byte we want an ack for */ - __u32 mss_cache; /* Cached effective mss, not including SACKS */ - __u32 ecn_flags; /* ECN status bits. */ - __u32 rate_delivered; /* saved rate sample: packets delivered */ - __u32 rate_interval_us; /* saved rate sample: time elapsed */ - __u32 packets_out; /* Packets which are "in flight" */ - __u32 retrans_out; /* Retransmitted packets out */ - __u32 total_retrans; /* Total retransmits for entire connection */ - __u32 segs_in; /* RFC4898 tcpEStatsPerfSegsIn - * total number of segments in. - */ - __u32 data_segs_in; /* RFC4898 tcpEStatsPerfDataSegsIn - * total number of data segments in. - */ - __u32 segs_out; /* RFC4898 tcpEStatsPerfSegsOut - * The total number of segments sent. - */ - __u32 data_segs_out; /* RFC4898 tcpEStatsPerfDataSegsOut - * total number of data segments sent. - */ - __u32 lost_out; /* Lost packets */ - __u32 sacked_out; /* SACK'd packets */ - __u64 bytes_received; /* RFC4898 tcpEStatsAppHCThruOctetsReceived - * sum(delta(rcv_nxt)), or how many bytes - * were acked. - */ - __u64 bytes_acked; /* RFC4898 tcpEStatsAppHCThruOctetsAcked - * sum(delta(snd_una)), or how many bytes - * were acked. - */ -}; - -struct bpf_sock_tuple { - union { - struct { - __be32 saddr; - __be32 daddr; - __be16 sport; - __be16 dport; - } ipv4; - struct { - __be32 saddr[4]; - __be32 daddr[4]; - __be16 sport; - __be16 dport; - } ipv6; - }; -}; - -#define XDP_PACKET_HEADROOM 256 - -/* User return codes for XDP prog type. - * A valid XDP program must return one of these defined values. All other - * return codes are reserved for future use. Unknown return codes will - * result in packet drops and a warning via bpf_warn_invalid_xdp_action(). - */ -enum xdp_action { - XDP_ABORTED = 0, - XDP_DROP, - XDP_PASS, - XDP_TX, - XDP_REDIRECT, -}; - -/* user accessible metadata for XDP packet hook - * new fields must be added to the end of this structure - */ -struct xdp_md { - __u32 data; - __u32 data_end; - __u32 data_meta; - /* Below access go through struct xdp_rxq_info */ - __u32 ingress_ifindex; /* rxq->dev->ifindex */ - __u32 rx_queue_index; /* rxq->queue_index */ -}; - -enum sk_action { - SK_DROP = 0, - SK_PASS, -}; - -/* user accessible metadata for SK_MSG packet hook, new fields must - * be added to the end of this structure - */ -struct sk_msg_md { - __bpf_md_ptr(void *, data); - __bpf_md_ptr(void *, data_end); - - __u32 family; - __u32 remote_ip4; /* Stored in network byte order */ - __u32 local_ip4; /* Stored in network byte order */ - __u32 remote_ip6[4]; /* Stored in network byte order */ - __u32 local_ip6[4]; /* Stored in network byte order */ - __u32 remote_port; /* Stored in network byte order */ - __u32 local_port; /* stored in host byte order */ - __u32 size; /* Total size of sk_msg */ -}; - -struct sk_reuseport_md { - /* - * Start of directly accessible data. It begins from - * the tcp/udp header. - */ - __bpf_md_ptr(void *, data); - /* End of directly accessible data */ - __bpf_md_ptr(void *, data_end); - /* - * Total length of packet (starting from the tcp/udp header). - * Note that the directly accessible bytes (data_end - data) - * could be less than this "len". Those bytes could be - * indirectly read by a helper "bpf_skb_load_bytes()". - */ - __u32 len; - /* - * Eth protocol in the mac header (network byte order). e.g. - * ETH_P_IP(0x0800) and ETH_P_IPV6(0x86DD) - */ - __u32 eth_protocol; - __u32 ip_protocol; /* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */ - __u32 bind_inany; /* Is sock bound to an INANY address? */ - __u32 hash; /* A hash of the packet 4 tuples */ -}; - -#define BPF_TAG_SIZE 8 - -struct bpf_prog_info { - __u32 type; - __u32 id; - __u8 tag[BPF_TAG_SIZE]; - __u32 jited_prog_len; - __u32 xlated_prog_len; - __aligned_u64 jited_prog_insns; - __aligned_u64 xlated_prog_insns; - __u64 load_time; /* ns since boottime */ - __u32 created_by_uid; - __u32 nr_map_ids; - __aligned_u64 map_ids; - char name[BPF_OBJ_NAME_LEN]; - __u32 ifindex; - __u32 gpl_compatible:1; - __u64 netns_dev; - __u64 netns_ino; - __u32 nr_jited_ksyms; - __u32 nr_jited_func_lens; - __aligned_u64 jited_ksyms; - __aligned_u64 jited_func_lens; - __u32 btf_id; - __u32 func_info_rec_size; - __aligned_u64 func_info; - __u32 nr_func_info; - __u32 nr_line_info; - __aligned_u64 line_info; - __aligned_u64 jited_line_info; - __u32 nr_jited_line_info; - __u32 line_info_rec_size; - __u32 jited_line_info_rec_size; - __u32 nr_prog_tags; - __aligned_u64 prog_tags; - __u64 run_time_ns; - __u64 run_cnt; -} __attribute__((aligned(8))); - -struct bpf_map_info { - __u32 type; - __u32 id; - __u32 key_size; - __u32 value_size; - __u32 max_entries; - __u32 map_flags; - char name[BPF_OBJ_NAME_LEN]; - __u32 ifindex; - __u32 :32; - __u64 netns_dev; - __u64 netns_ino; - __u32 btf_id; - __u32 btf_key_type_id; - __u32 btf_value_type_id; -} __attribute__((aligned(8))); - -struct bpf_btf_info { - __aligned_u64 btf; - __u32 btf_size; - __u32 id; -} __attribute__((aligned(8))); - -/* User bpf_sock_addr struct to access socket fields and sockaddr struct passed - * by user and intended to be used by socket (e.g. to bind to, depends on - * attach attach type). - */ -struct bpf_sock_addr { - __u32 user_family; /* Allows 4-byte read, but no write. */ - __u32 user_ip4; /* Allows 1,2,4-byte read and 4-byte write. - * Stored in network byte order. - */ - __u32 user_ip6[4]; /* Allows 1,2,4-byte read an 4-byte write. - * Stored in network byte order. - */ - __u32 user_port; /* Allows 4-byte read and write. - * Stored in network byte order - */ - __u32 family; /* Allows 4-byte read, but no write */ - __u32 type; /* Allows 4-byte read, but no write */ - __u32 protocol; /* Allows 4-byte read, but no write */ - __u32 msg_src_ip4; /* Allows 1,2,4-byte read an 4-byte write. - * Stored in network byte order. - */ - __u32 msg_src_ip6[4]; /* Allows 1,2,4-byte read an 4-byte write. - * Stored in network byte order. - */ -}; - -/* User bpf_sock_ops struct to access socket values and specify request ops - * and their replies. - * Some of this fields are in network (bigendian) byte order and may need - * to be converted before use (bpf_ntohl() defined in samples/bpf/bpf_endian.h). - * New fields can only be added at the end of this structure - */ -struct bpf_sock_ops { - __u32 op; - union { - __u32 args[4]; /* Optionally passed to bpf program */ - __u32 reply; /* Returned by bpf program */ - __u32 replylong[4]; /* Optionally returned by bpf prog */ - }; - __u32 family; - __u32 remote_ip4; /* Stored in network byte order */ - __u32 local_ip4; /* Stored in network byte order */ - __u32 remote_ip6[4]; /* Stored in network byte order */ - __u32 local_ip6[4]; /* Stored in network byte order */ - __u32 remote_port; /* Stored in network byte order */ - __u32 local_port; /* stored in host byte order */ - __u32 is_fullsock; /* Some TCP fields are only valid if - * there is a full socket. If not, the - * fields read as zero. - */ - __u32 snd_cwnd; - __u32 srtt_us; /* Averaged RTT << 3 in usecs */ - __u32 bpf_sock_ops_cb_flags; /* flags defined in uapi/linux/tcp.h */ - __u32 state; - __u32 rtt_min; - __u32 snd_ssthresh; - __u32 rcv_nxt; - __u32 snd_nxt; - __u32 snd_una; - __u32 mss_cache; - __u32 ecn_flags; - __u32 rate_delivered; - __u32 rate_interval_us; - __u32 packets_out; - __u32 retrans_out; - __u32 total_retrans; - __u32 segs_in; - __u32 data_segs_in; - __u32 segs_out; - __u32 data_segs_out; - __u32 lost_out; - __u32 sacked_out; - __u32 sk_txhash; - __u64 bytes_received; - __u64 bytes_acked; -}; - -/* Definitions for bpf_sock_ops_cb_flags */ -#define BPF_SOCK_OPS_RTO_CB_FLAG (1<<0) -#define BPF_SOCK_OPS_RETRANS_CB_FLAG (1<<1) -#define BPF_SOCK_OPS_STATE_CB_FLAG (1<<2) -#define BPF_SOCK_OPS_ALL_CB_FLAGS 0x7 /* Mask of all currently - * supported cb flags - */ - -/* List of known BPF sock_ops operators. - * New entries can only be added at the end - */ -enum { - BPF_SOCK_OPS_VOID, - BPF_SOCK_OPS_TIMEOUT_INIT, /* Should return SYN-RTO value to use or - * -1 if default value should be used - */ - BPF_SOCK_OPS_RWND_INIT, /* Should return initial advertized - * window (in packets) or -1 if default - * value should be used - */ - BPF_SOCK_OPS_TCP_CONNECT_CB, /* Calls BPF program right before an - * active connection is initialized - */ - BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB, /* Calls BPF program when an - * active connection is - * established - */ - BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB, /* Calls BPF program when a - * passive connection is - * established - */ - BPF_SOCK_OPS_NEEDS_ECN, /* If connection's congestion control - * needs ECN - */ - BPF_SOCK_OPS_BASE_RTT, /* Get base RTT. The correct value is - * based on the path and may be - * dependent on the congestion control - * algorithm. In general it indicates - * a congestion threshold. RTTs above - * this indicate congestion - */ - BPF_SOCK_OPS_RTO_CB, /* Called when an RTO has triggered. - * Arg1: value of icsk_retransmits - * Arg2: value of icsk_rto - * Arg3: whether RTO has expired - */ - BPF_SOCK_OPS_RETRANS_CB, /* Called when skb is retransmitted. - * Arg1: sequence number of 1st byte - * Arg2: # segments - * Arg3: return value of - * tcp_transmit_skb (0 => success) - */ - BPF_SOCK_OPS_STATE_CB, /* Called when TCP changes state. - * Arg1: old_state - * Arg2: new_state - */ - BPF_SOCK_OPS_TCP_LISTEN_CB, /* Called on listen(2), right after - * socket transition to LISTEN state. - */ -}; - -/* List of TCP states. There is a build check in net/ipv4/tcp.c to detect - * changes between the TCP and BPF versions. Ideally this should never happen. - * If it does, we need to add code to convert them before calling - * the BPF sock_ops function. - */ -enum { - BPF_TCP_ESTABLISHED = 1, - BPF_TCP_SYN_SENT, - BPF_TCP_SYN_RECV, - BPF_TCP_FIN_WAIT1, - BPF_TCP_FIN_WAIT2, - BPF_TCP_TIME_WAIT, - BPF_TCP_CLOSE, - BPF_TCP_CLOSE_WAIT, - BPF_TCP_LAST_ACK, - BPF_TCP_LISTEN, - BPF_TCP_CLOSING, /* Now a valid state */ - BPF_TCP_NEW_SYN_RECV, - - BPF_TCP_MAX_STATES /* Leave at the end! */ -}; - -#define TCP_BPF_IW 1001 /* Set TCP initial congestion window */ -#define TCP_BPF_SNDCWND_CLAMP 1002 /* Set sndcwnd_clamp */ - -struct bpf_perf_event_value { - __u64 counter; - __u64 enabled; - __u64 running; -}; - -#define BPF_DEVCG_ACC_MKNOD (1ULL << 0) -#define BPF_DEVCG_ACC_READ (1ULL << 1) -#define BPF_DEVCG_ACC_WRITE (1ULL << 2) - -#define BPF_DEVCG_DEV_BLOCK (1ULL << 0) -#define BPF_DEVCG_DEV_CHAR (1ULL << 1) - -struct bpf_cgroup_dev_ctx { - /* access_type encoded as (BPF_DEVCG_ACC_* << 16) | BPF_DEVCG_DEV_* */ - __u32 access_type; - __u32 major; - __u32 minor; -}; - -struct bpf_raw_tracepoint_args { - __u64 args[0]; -}; - -/* DIRECT: Skip the FIB rules and go to FIB table associated with device - * OUTPUT: Do lookup from egress perspective; default is ingress - */ -#define BPF_FIB_LOOKUP_DIRECT BIT(0) -#define BPF_FIB_LOOKUP_OUTPUT BIT(1) - -enum { - BPF_FIB_LKUP_RET_SUCCESS, /* lookup successful */ - BPF_FIB_LKUP_RET_BLACKHOLE, /* dest is blackholed; can be dropped */ - BPF_FIB_LKUP_RET_UNREACHABLE, /* dest is unreachable; can be dropped */ - BPF_FIB_LKUP_RET_PROHIBIT, /* dest not allowed; can be dropped */ - BPF_FIB_LKUP_RET_NOT_FWDED, /* packet is not forwarded */ - BPF_FIB_LKUP_RET_FWD_DISABLED, /* fwding is not enabled on ingress */ - BPF_FIB_LKUP_RET_UNSUPP_LWT, /* fwd requires encapsulation */ - BPF_FIB_LKUP_RET_NO_NEIGH, /* no neighbor entry for nh */ - BPF_FIB_LKUP_RET_FRAG_NEEDED, /* fragmentation required to fwd */ -}; - -struct bpf_fib_lookup { - /* input: network family for lookup (AF_INET, AF_INET6) - * output: network family of egress nexthop - */ - __u8 family; - - /* set if lookup is to consider L4 data - e.g., FIB rules */ - __u8 l4_protocol; - __be16 sport; - __be16 dport; - - /* total length of packet from network header - used for MTU check */ - __u16 tot_len; - - /* input: L3 device index for lookup - * output: device index from FIB lookup - */ - __u32 ifindex; - - union { - /* inputs to lookup */ - __u8 tos; /* AF_INET */ - __be32 flowinfo; /* AF_INET6, flow_label + priority */ - - /* output: metric of fib result (IPv4/IPv6 only) */ - __u32 rt_metric; - }; - - union { - __be32 ipv4_src; - __u32 ipv6_src[4]; /* in6_addr; network order */ - }; - - /* input to bpf_fib_lookup, ipv{4,6}_dst is destination address in - * network header. output: bpf_fib_lookup sets to gateway address - * if FIB lookup returns gateway route - */ - union { - __be32 ipv4_dst; - __u32 ipv6_dst[4]; /* in6_addr; network order */ - }; - - /* output */ - __be16 h_vlan_proto; - __be16 h_vlan_TCI; - __u8 smac[6]; /* ETH_ALEN */ - __u8 dmac[6]; /* ETH_ALEN */ -}; - -enum bpf_task_fd_type { - BPF_FD_TYPE_RAW_TRACEPOINT, /* tp name */ - BPF_FD_TYPE_TRACEPOINT, /* tp name */ - BPF_FD_TYPE_KPROBE, /* (symbol + offset) or addr */ - BPF_FD_TYPE_KRETPROBE, /* (symbol + offset) or addr */ - BPF_FD_TYPE_UPROBE, /* filename + offset */ - BPF_FD_TYPE_URETPROBE, /* filename + offset */ -}; - -struct bpf_flow_keys { - __u16 nhoff; - __u16 thoff; - __u16 addr_proto; /* ETH_P_* of valid addrs */ - __u8 is_frag; - __u8 is_first_frag; - __u8 is_encap; - __u8 ip_proto; - __be16 n_proto; - __be16 sport; - __be16 dport; - union { - struct { - __be32 ipv4_src; - __be32 ipv4_dst; - }; - struct { - __u32 ipv6_src[4]; /* in6_addr; network order */ - __u32 ipv6_dst[4]; /* in6_addr; network order */ - }; - }; -}; - -struct bpf_func_info { - __u32 insn_off; - __u32 type_id; -}; - -#define BPF_LINE_INFO_LINE_NUM(line_col) ((line_col) >> 10) -#define BPF_LINE_INFO_LINE_COL(line_col) ((line_col) & 0x3ff) - -struct bpf_line_info { - __u32 insn_off; - __u32 file_name_off; - __u32 line_off; - __u32 line_col; -}; - -struct bpf_spin_lock { - __u32 val; -}; -#endif /* _UAPI__LINUX_BPF_H__ */ |