extra: ipv6pool module

2 files changed, 214 insertions, 0 deletions

diff --git a/accel-pppd/extra/CMakeLists.txt b/accel-pppd/extra/CMakeLists.txt
index 21449061..cefc4167 100644
--- a/accel-pppd/extra/CMakeLists.txt
+++ b/accel-pppd/extra/CMakeLists.txt
@@ -1,5 +1,6 @@
 ADD_LIBRARY(pppd_compat SHARED pppd_compat.c)
 ADD_LIBRARY(ippool SHARED ippool.c)
+ADD_LIBRARY(ipv6pool SHARED ipv6pool.c)
 ADD_LIBRARY(sigchld SHARED sigchld.c)
 ADD_LIBRARY(chap-secrets SHARED chap-secrets.c)
 
diff --git a/accel-pppd/extra/ipv6pool.c b/accel-pppd/extra/ipv6pool.c
new file mode 100644
index 00000000..37d2ea89
--- /dev/null
+++ b/accel-pppd/extra/ipv6pool.c
@@ -0,0 +1,213 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <arpa/inet.h>
+#include <endian.h>
+
+#include "ipdb.h"
+#include "list.h"
+#include "log.h"
+#include "spinlock.h"
+
+#include "memdebug.h"
+
+
+#define INTF_ID_FIXED  0
+#define INTF_ID_RANDOM 1
+#define INTF_ID_CSID   2
+#define INTF_ID_IPV4   3
+
+static int conf_intf_id = INTF_ID_FIXED;
+static uint64_t conf_intf_id_val = 2;
+
+struct ippool_item_t
+{
+	struct list_head entry;
+	struct ipv6db_item_t it;
+};
+
+static LIST_HEAD(ippool);
+static spinlock_t pool_lock = SPINLOCK_INITIALIZER;
+static struct ipdb_t ipdb;
+static int urandom_fd;
+
+static void generate_pool(struct in6_addr *addr, int mask, int prefix_len)
+{
+	struct ippool_item_t *it;
+	uint64_t ip, endip, step;
+
+	ip = be64toh(*(uint64_t *)addr->s6_addr);
+	endip = ip | ((1llu << (64 - mask)) - 1);
+	step = 1 << (64 - prefix_len);
+	
+	for (; ip <= endip; ip += step) {
+		it = malloc(sizeof(*it));
+		*(uint64_t *)it->it.addr.s6_addr = htobe64(ip);
+		list_add_tail(&it->entry, &ippool);
+	}
+}
+
+static void add_prefix(const char *_val)
+{
+	char *val = _strdup(_val);
+	char *ptr1, *ptr2;
+	struct in6_addr addr;
+	int prefix_len;
+	int mask;
+	
+	ptr1 = strchr(val, '/');
+	if (!ptr1)
+		goto err;
+	
+	*ptr1 = 0;
+
+	ptr2 = strchr(ptr1 + 1, ',');
+	if (!ptr2)
+		goto err;
+	
+	*ptr2 = 0;
+
+	if (inet_pton(AF_INET6, val, &addr) == 0)
+		goto err;
+	
+	if (sscanf(ptr1 + 1, "%i", &mask) != 1)
+		goto err;
+	
+	if (mask < 7 || mask > 64)
+		goto err;
+	
+	if (sscanf(ptr2 + 1, "%i", &prefix_len) != 1)
+		goto err;
+	
+	if (prefix_len > 64  || prefix_len < mask)
+		goto err;
+	
+	generate_pool(&addr, mask, prefix_len);
+
+	_free(val);
+	return;
+	
+err:
+	log_error("ipv6_pool: failed to parse '%s'\n", _val);
+	_free(val);
+}
+
+static void generate_intf_id(struct ppp_t *ppp, struct in6_addr *addr)
+{
+	char str[4];
+	int i, n;
+	
+	switch (conf_intf_id) {
+		case INTF_ID_FIXED:
+			*(uint64_t *)(&addr->s6_addr32[2]) = conf_intf_id_val;
+			break;
+		case INTF_ID_RANDOM:
+			read(urandom_fd, &addr->s6_addr32[2], 8);
+			break;
+		case INTF_ID_CSID:
+			break;
+		case INTF_ID_IPV4:
+			for (i = 0; i < 4; i++) {
+				sprintf(str, "%i", (ppp->peer_ipaddr >> (i*8)) & 0xff);
+				sscanf(str, "%x", &n);
+				addr->s6_addr16[4 + i] = htons(n);
+			}
+	}
+}
+
+static struct ipv6db_item_t *get_ip(struct ppp_t *ppp)
+{
+	struct ippool_item_t *it;
+
+	spin_lock(&pool_lock);
+	if (!list_empty(&ippool)) {
+		it = list_entry(ippool.next, typeof(*it), entry);
+		list_del(&it->entry);
+	} else
+		it = NULL;
+	spin_unlock(&pool_lock);
+
+	if (it)
+		generate_intf_id(ppp, &it->it.addr);
+
+	return it ? &it->it : NULL;
+}
+
+static void put_ip(struct ppp_t *ppp, struct ipv6db_item_t *it)
+{
+	struct ippool_item_t *pit = container_of(it, typeof(*pit), it);
+
+	spin_lock(&pool_lock);
+	list_add_tail(&pit->entry, &ippool);
+	spin_unlock(&pool_lock);
+}
+
+static struct ipdb_t ipdb = {
+	.get_ipv6 = get_ip,
+	.put_ipv6 = put_ip,
+};
+
+static uint64_t parse_intfid(const char *opt)
+{
+	union {
+		uint64_t u64;
+		uint16_t u16[4];
+	} u;
+
+	int n[4];
+	int i;
+
+	if (sscanf(opt, "%x:%x:%x:%x", &n[0], &n[1], &n[2], &n[3]) != 4)
+		goto err;
+	
+	for (i = 0; i < 4; i++) {
+		if (n[i] < 0 || n[i] > 0xffff)
+			goto err;
+		u.u16[i] = htons(n[i]);
+	}
+
+	return u.u64;
+
+err:
+	log_error("ipv6pool: failed to parse intf-id\n");
+	conf_intf_id = INTF_ID_RANDOM;
+	return 0;
+}
+
+static void ippool_init(void)
+{
+	struct conf_sect_t *s = conf_get_section("ipv6-pool");
+	struct conf_option_t *opt;
+	
+	if (!s)
+		return;
+	
+	list_for_each_entry(opt, &s->items, entry) {
+		if (!strcmp(opt->name, "intf-id")) {
+			if (!strcmp(opt->val, "random"))
+				conf_intf_id = INTF_ID_RANDOM;
+			else if (!strcmp(opt->val, "calling-sid"))
+				conf_intf_id = INTF_ID_CSID;
+			else if (!strcmp(opt->val, "ipv4"))
+				conf_intf_id = INTF_ID_IPV4;
+			else {
+				conf_intf_id = INTF_ID_FIXED;
+				conf_intf_id_val = parse_intfid(opt->val);
+			}
+		}
+		if (opt->val)
+			continue;
+		add_prefix(opt->name);
+	}
+
+	urandom_fd = open("/dev/urandom", O_RDONLY);
+
+	ipdb_register(&ipdb);
+}
+
+DEFINE_INIT(101, ippool_init);
+