diff options
Diffstat (limited to 'extensions/libct_proto_sctp.c')
| -rw-r--r-- | extensions/libct_proto_sctp.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/extensions/libct_proto_sctp.c b/extensions/libct_proto_sctp.c new file mode 100644 index 0000000..f4c94df --- /dev/null +++ b/extensions/libct_proto_sctp.c @@ -0,0 +1,246 @@ +/* + * (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ +#include <stdio.h> +#include <getopt.h> +#include <stdlib.h> +#include <string.h> +#include <netinet/in.h> /* For htons */ +#include <libnetfilter_conntrack/libnetfilter_conntrack.h> +#include <libnetfilter_conntrack/libnetfilter_conntrack_sctp.h> + +#include "conntrack.h" + +#ifndef IPPROTO_SCTP +#define IPPROTO_SCTP 132 +#endif + +enum { + CT_SCTP_ORIG_SPORT = (1 << 0), + CT_SCTP_ORIG_DPORT = (1 << 1), + CT_SCTP_REPL_SPORT = (1 << 2), + CT_SCTP_REPL_DPORT = (1 << 3), + CT_SCTP_MASK_SPORT = (1 << 4), + CT_SCTP_MASK_DPORT = (1 << 5), + CT_SCTP_STATE = (1 << 6), + CT_SCTP_EXPTUPLE_SPORT = (1 << 7), + CT_SCTP_EXPTUPLE_DPORT = (1 << 8), + CT_SCTP_ORIG_VTAG = (1 << 9), + CT_SCTP_REPL_VTAG = (1 << 10), +}; + +#define SCTP_OPT_MAX 14 +static struct option opts[SCTP_OPT_MAX] = { + { .name = "orig-port-src", .has_arg = 1, .val = 1 }, + { .name = "orig-port-dst", .has_arg = 1, .val = 2 }, + { .name = "reply-port-src", .has_arg = 1, .val = 3 }, + { .name = "reply-port-dst", .has_arg = 1, .val = 4 }, + { .name = "mask-port-src", .has_arg = 1, .val = 5 }, + { .name = "mask-port-dst", .has_arg = 1, .val = 6 }, + { .name = "state", .has_arg = 1, .val = 7 }, + { .name = "tuple-port-src", .has_arg = 1, .val = 8 }, + { .name = "tuple-port-dst", .has_arg = 1, .val = 9 }, + { .name = "orig-vtag", .has_arg = 1, .val = 10 }, + { .name = "reply-vtag", .has_arg = 1, .val = 11 }, + { .name = "sport", .has_arg = 1, .val = 1 }, /* alias */ + { .name = "dport", .has_arg = 1, .val = 2 }, /* alias */ + {0, 0, 0, 0} +}; + +static const char *sctp_optflags[SCTP_OPT_MAX] = { + [0] = "sport", + [1] = "dport", + [2] = "reply-port-src", + [3] = "reply-port-dst", + [4] = "mask-port-src", + [5] = "mask-port-dst", + [6] = "state", + [7] = "tuple-port-src", + [8] = "tuple-port-dst", + [9] = "orig-vtag", + [10] = "reply-vtag", +}; + +static char sctp_commands_v_options[NUMBER_OF_CMD][SCTP_OPT_MAX] = +/* Well, it's better than "Re: Sevilla vs Betis" */ +{ + /* 1 2 3 4 5 6 7 8 9 10 11*/ +/*CT_LIST*/ {2,2,2,2,0,0,2,0,0,0,0}, +/*CT_CREATE*/ {3,3,3,3,0,0,1,0,0,1,1}, +/*CT_UPDATE*/ {2,2,2,2,0,0,2,0,0,2,2}, +/*CT_DELETE*/ {2,2,2,2,0,0,2,0,0,0,0}, +/*CT_GET*/ {3,3,3,3,0,0,2,0,0,2,2}, +/*CT_FLUSH*/ {0,0,0,0,0,0,0,0,0,0,0}, +/*CT_EVENT*/ {2,2,2,2,0,0,2,0,0,0,0}, +/*CT_VERSION*/ {0,0,0,0,0,0,0,0,0,0,0}, +/*CT_HELP*/ {0,0,0,0,0,0,0,0,0,0,0}, +/*EXP_LIST*/ {0,0,0,0,0,0,0,0,0,0,0}, +/*EXP_CREATE*/ {1,1,1,1,1,1,0,1,1,1,1}, +/*EXP_DELETE*/ {1,1,1,1,0,0,0,0,0,0,0}, +/*EXP_GET*/ {1,1,1,1,0,0,0,0,0,0,0}, +/*EXP_FLUSH*/ {0,0,0,0,0,0,0,0,0,0,0}, +/*EXP_EVENT*/ {0,0,0,0,0,0,0,0,0,0,0}, +}; + +static const char *sctp_states[SCTP_CONNTRACK_MAX] = { + [SCTP_CONNTRACK_NONE] = "NONE", + [SCTP_CONNTRACK_CLOSED] = "CLOSED", + [SCTP_CONNTRACK_COOKIE_WAIT] = "COOKIE_WAIT", + [SCTP_CONNTRACK_COOKIE_ECHOED] = "COOKIE_ECHOED", + [SCTP_CONNTRACK_ESTABLISHED] = "ESTABLISHED", + [SCTP_CONNTRACK_SHUTDOWN_SENT] = "SHUTDOWN_SENT", + [SCTP_CONNTRACK_SHUTDOWN_RECD] = "SHUTDOWN_RECD", + [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = "SHUTDOWN_ACK_SENT", +}; + +static void help(void) +{ + fprintf(stdout, " --orig-port-src\t\toriginal source port\n"); + fprintf(stdout, " --orig-port-dst\t\toriginal destination port\n"); + fprintf(stdout, " --reply-port-src\t\treply source port\n"); + fprintf(stdout, " --reply-port-dst\t\treply destination port\n"); + fprintf(stdout, " --mask-port-src\t\tmask source port\n"); + fprintf(stdout, " --mask-port-dst\t\tmask destination port\n"); + fprintf(stdout, " --tuple-port-src\t\texpectation tuple src port\n"); + fprintf(stdout, " --tuple-port-src\t\texpectation tuple dst port\n"); + fprintf(stdout, " --state\t\t\tSCTP state, fe. ESTABLISHED\n"); + fprintf(stdout, " --orig-vtag\t\toriginal verification tag\n"); + fprintf(stdout, " --reply-vtag\t\treply verification tag\n"); +} + +static int +parse_options(char c, struct nf_conntrack *ct, + struct nf_conntrack *exptuple, struct nf_conntrack *mask, + unsigned int *flags) +{ + int i; + u_int16_t port; + u_int32_t vtag; + + switch(c) { + case 1: + port = htons(atoi(optarg)); + nfct_set_attr_u16(ct, ATTR_ORIG_PORT_SRC, port); + nfct_set_attr_u8(ct, ATTR_ORIG_L4PROTO, IPPROTO_SCTP); + *flags |= CT_SCTP_ORIG_SPORT; + break; + case 2: + port = htons(atoi(optarg)); + nfct_set_attr_u16(ct, ATTR_ORIG_PORT_DST, port); + nfct_set_attr_u8(ct, ATTR_ORIG_L4PROTO, IPPROTO_SCTP); + *flags |= CT_SCTP_ORIG_DPORT; + break; + case 3: + port = htons(atoi(optarg)); + nfct_set_attr_u16(ct, ATTR_REPL_PORT_SRC, port); + nfct_set_attr_u8(ct, ATTR_REPL_L4PROTO, IPPROTO_SCTP); + *flags |= CT_SCTP_REPL_SPORT; + break; + case 4: + port = htons(atoi(optarg)); + nfct_set_attr_u16(ct, ATTR_REPL_PORT_DST, port); + nfct_set_attr_u8(ct, ATTR_REPL_L4PROTO, IPPROTO_SCTP); + *flags |= CT_SCTP_REPL_DPORT; + break; + case 5: + port = htons(atoi(optarg)); + nfct_set_attr_u16(mask, ATTR_ORIG_PORT_SRC, port); + nfct_set_attr_u8(mask, ATTR_ORIG_L4PROTO, IPPROTO_SCTP); + *flags |= CT_SCTP_MASK_SPORT; + break; + case 6: + port = htons(atoi(optarg)); + nfct_set_attr_u16(mask, ATTR_ORIG_PORT_DST, port); + nfct_set_attr_u8(mask, ATTR_ORIG_L4PROTO, IPPROTO_SCTP); + *flags |= CT_SCTP_MASK_DPORT; + break; + case 7: + for (i=0; i<SCTP_CONNTRACK_MAX; i++) { + if (strcmp(optarg, sctp_states[i]) == 0) { + nfct_set_attr_u8(ct, ATTR_SCTP_STATE, i); + break; + } + } + if (i == SCTP_CONNTRACK_MAX) + exit_error(PARAMETER_PROBLEM, + "unknown SCTP state `%s'", optarg); + *flags |= CT_SCTP_STATE; + break; + case 8: + port = htons(atoi(optarg)); + nfct_set_attr_u16(exptuple, ATTR_ORIG_PORT_SRC, port); + nfct_set_attr_u8(exptuple, ATTR_ORIG_L4PROTO, port); + *flags |= CT_SCTP_EXPTUPLE_SPORT; + break; + case 9: + port = htons(atoi(optarg)); + nfct_set_attr_u16(exptuple, ATTR_ORIG_PORT_DST, port); + nfct_set_attr_u8(exptuple, ATTR_ORIG_L4PROTO, port); + *flags |= CT_SCTP_EXPTUPLE_DPORT; + break; + case 10: + vtag = htonl(atoi(optarg)); + nfct_set_attr_u32(ct, ATTR_SCTP_VTAG_ORIG, vtag); + *flags |= CT_SCTP_ORIG_VTAG; + break; + case 11: + vtag = htonl(atoi(optarg)); + nfct_set_attr_u32(ct, ATTR_SCTP_VTAG_REPL, vtag); + *flags |= CT_SCTP_REPL_VTAG; + break; + } + return 1; +} + +#define SCTP_VALID_FLAGS_MAX 2 +static unsigned int dccp_valid_flags[SCTP_VALID_FLAGS_MAX] = { + CT_SCTP_ORIG_SPORT | CT_SCTP_ORIG_DPORT, + CT_SCTP_REPL_SPORT | CT_SCTP_REPL_DPORT, +}; + +static void +final_check(unsigned int flags, unsigned int cmd, struct nf_conntrack *ct) +{ + int ret, partial; + + ret = generic_opt_check(flags, SCTP_OPT_MAX, + sctp_commands_v_options[cmd], sctp_optflags, + dccp_valid_flags, SCTP_VALID_FLAGS_MAX, + &partial); + if (!ret) { + switch(partial) { + case -1: + case 0: + exit_error(PARAMETER_PROBLEM, "you have to specify " + "`--sport' and " + "`--dport'"); + break; + case 1: + exit_error(PARAMETER_PROBLEM, "you have to specify " + "`--reply-src-port' and " + "`--reply-dst-port'"); + break; + } + } +} + +static struct ctproto_handler sctp = { + .name = "sctp", + .protonum = IPPROTO_SCTP, + .parse_opts = parse_options, + .final_check = final_check, + .help = help, + .opts = opts, + .version = VERSION, +}; + +void register_sctp(void) +{ + register_proto(&sctp); +} |