2 * firewall3 - 3rd OpenWrt UCI firewall implementation
4 * Copyright (C) 2013 Jo-Philipp Wich <jo@mein.io>
6 * Permission to use, copy, modify, and/or distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22 #include <sys/ioctl.h>
31 static int fw3_lock_fd = -1;
32 static pid_t pipe_pid = -1;
33 static FILE *pipe_fd = NULL;
35 bool fw3_pr_debug = false;
39 warn_elem_section_name(struct uci_section *s, bool find_name)
43 struct uci_element *tmp;
47 uci_foreach_element(&s->package->sections, tmp)
49 if (strcmp(uci_to_section(tmp)->type, s->type))
58 fprintf(stderr, "@%s[%d]", s->type, i);
62 uci_foreach_element(&s->options, tmp)
64 o = uci_to_option(tmp);
66 if (!strcmp(tmp->name, "name") && (o->type == UCI_TYPE_STRING))
68 fprintf(stderr, " (%s)", o->v.string);
76 fprintf(stderr, "'%s'", s->e.name);
84 warn_elem(struct uci_element *e, const char *format, ...)
86 if (e->type == UCI_TYPE_SECTION)
88 fprintf(stderr, "Warning: Section ");
89 warn_elem_section_name(uci_to_section(e), true);
91 else if (e->type == UCI_TYPE_OPTION)
93 fprintf(stderr, "Warning: Option ");
94 warn_elem_section_name(uci_to_option(e)->section, false);
95 fprintf(stderr, ".%s ", e->name);
99 va_start(argptr, format);
100 vfprintf(stderr, format, argptr);
103 fprintf(stderr, "\n");
107 warn(const char* format, ...)
109 fprintf(stderr, "Warning: ");
111 va_start(argptr, format);
112 vfprintf(stderr, format, argptr);
114 fprintf(stderr, "\n");
118 error(const char* format, ...)
120 fprintf(stderr, "Error: ");
122 va_start(argptr, format);
123 vfprintf(stderr, format, argptr);
125 fprintf(stderr, "\n");
131 info(const char* format, ...)
134 va_start(argptr, format);
135 vfprintf(stderr, format, argptr);
137 fprintf(stderr, "\n");
141 fw3_alloc(size_t size)
145 mem = calloc(1, size);
148 error("Out of memory while allocating %zd bytes", size);
154 fw3_strdup(const char *s)
161 error("Out of memory while duplicating string '%s'", s);
167 fw3_find_command(const char *cmd)
170 int plen = 0, clen = strlen(cmd) + 1;
172 static char path[PATH_MAX];
174 if (!stat(cmd, &s) && S_ISREG(s.st_mode))
177 search = getenv("PATH");
180 search = "/bin:/usr/bin:/sbin:/usr/sbin";
186 if (*p != ':' && *p != '\0')
191 if ((plen + clen) >= sizeof(path))
194 snprintf(path, sizeof(path), "%.*s/%s", plen, search, cmd);
196 if (!stat(path, &s) && S_ISREG(s.st_mode))
207 fw3_stdout_pipe(void)
214 __fw3_command_pipe(bool silent, const char *command, ...)
220 char *arg, **args, **tmp;
222 command = fw3_find_command(command);
231 args = calloc(argn, sizeof(arg));
236 args[0] = (char *)command;
239 va_start(argp, command);
241 while ((arg = va_arg(argp, char *)) != NULL)
243 tmp = realloc(args, ++argn * sizeof(arg));
255 switch ((pid = fork()))
272 execv(command, args);
275 signal(SIGPIPE, SIG_IGN);
278 fcntl(pfds[1], F_SETFD, fcntl(pfds[1], F_GETFD) | FD_CLOEXEC);
281 pipe_fd = fdopen(pfds[1], "w");
287 fw3_pr(const char *fmt, ...)
291 if (fw3_pr_debug && pipe_fd != stdout)
294 vfprintf(stderr, fmt, args);
299 vfprintf(pipe_fd, fmt, args);
304 fw3_command_close(void)
306 if (pipe_fd && pipe_fd != stdout)
310 waitpid(pipe_pid, NULL, 0);
312 signal(SIGPIPE, SIG_DFL);
319 fw3_has_table(bool ipv6, const char *table)
326 const char *path = ipv6
327 ? "/proc/net/ip6_tables_names" : "/proc/net/ip_tables_names";
329 if (!(f = fopen(path, "r")))
332 while (fgets(line, sizeof(line), f))
334 if (!strncmp(line, table, strlen(table)))
347 fw3_has_target(const bool ipv6, const char *target)
354 const char *path = ipv6
355 ? "/proc/net/ip6_tables_targets" : "/proc/net/ip_tables_targets";
357 if (!(f = fopen(path, "r")))
360 while (fgets(line, sizeof(line), f))
362 if (!strcmp(line, target))
375 fw3_lock_path(int *fd, const char *path)
377 int lock_fd = open(path, O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR);
381 warn("Cannot create lock file %s: %s", path, strerror(errno));
385 if (flock(lock_fd, LOCK_EX))
387 warn("Cannot acquire exclusive lock: %s", strerror(errno));
400 return fw3_lock_path(&fw3_lock_fd, FW3_LOCKFILE);
405 fw3_unlock_path(int *fd, const char *lockpath)
410 if (flock(*fd, LOCK_UN))
411 warn("Cannot release exclusive lock: %s", strerror(errno));
414 unlink(FW3_LOCKFILE);
423 fw3_unlock_path(&fw3_lock_fd, FW3_LOCKFILE);
428 write_defaults_uci(struct uci_context *ctx, struct fw3_defaults *d,
429 struct uci_package *dest)
431 char buf[sizeof("0xffffffff")];
432 struct uci_ptr ptr = { .p = dest };
434 uci_add_section(ctx, dest, "defaults", &ptr.s);
437 ptr.option = "input";
438 ptr.value = fw3_flag_names[d->policy_input];
442 ptr.option = "output";
443 ptr.value = fw3_flag_names[d->policy_output];
447 ptr.option = "forward";
448 ptr.value = fw3_flag_names[d->policy_forward];
451 snprintf(buf, sizeof(buf), "0x%x", d->flags[0]);
453 ptr.option = "__flags_v4";
457 snprintf(buf, sizeof(buf), "0x%x", d->flags[1]);
459 ptr.option = "__flags_v6";
465 write_zone_uci(struct uci_context *ctx, struct fw3_zone *z,
466 struct uci_package *dest, struct ifaddrs *ifaddr)
468 struct fw3_device *dev;
469 struct fw3_address *sub;
471 enum fw3_family fam = FW3_FAMILY_ANY;
473 char *p, buf[INET6_ADDRSTRLEN];
475 struct uci_ptr ptr = { .p = dest };
480 if (fw3_no_table(z->flags[0]) && !fw3_no_table(z->flags[1]))
482 else if (!fw3_no_table(z->flags[0]) && fw3_no_table(z->flags[1]))
484 else if (fw3_no_table(z->flags[0]) && fw3_no_table(z->flags[1]))
487 uci_add_section(ctx, dest, "zone", &ptr.s);
495 ptr.option = "input";
496 ptr.value = fw3_flag_names[z->policy_input];
500 ptr.option = "output";
501 ptr.value = fw3_flag_names[z->policy_output];
505 ptr.option = "forward";
506 ptr.value = fw3_flag_names[z->policy_forward];
511 ptr.value = z->masq ? "1" : "0";
515 ptr.option = "mtu_fix";
516 ptr.value = z->mtu_fix ? "1" : "0";
520 ptr.option = "custom_chains";
521 ptr.value = z->custom_chains ? "1" : "0";
524 if (fam != FW3_FAMILY_ANY)
527 ptr.option = "family";
528 ptr.value = fw3_flag_names[fam];
533 ptr.option = "device";
535 fw3_foreach(dev, &z->devices)
543 ep = buf + sizeof(buf);
546 p += snprintf(p, ep - p, "!");
549 p += snprintf(p, ep - p, "%s@%s", dev->name, dev->network);
551 p += snprintf(p, ep - p, "%s", dev->name);
554 uci_add_list(ctx, &ptr);
558 ptr.option = "subnet";
560 fw3_foreach(sub, &z->subnets)
565 ptr.value = fw3_address_to_string(sub, true, false);
566 uci_add_list(ctx, &ptr);
570 ptr.option = "__addrs";
572 fw3_foreach(dev, &z->devices)
577 for (ifa = ifaddr; ifa; ifa = ifa->ifa_next)
579 if (!ifa->ifa_addr || strcmp(dev->name, ifa->ifa_name))
582 if (ifa->ifa_addr->sa_family == AF_INET)
584 &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr,
586 else if (ifa->ifa_addr->sa_family == AF_INET6)
588 &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr,
594 uci_add_list(ctx, &ptr);
601 ptr.option = "extra_src";
602 ptr.value = z->extra_src;
609 ptr.option = "extra_dest";
610 ptr.value = z->extra_dest;
614 snprintf(buf, sizeof(buf), "0x%x", z->flags[0]);
616 ptr.option = "__flags_v4";
620 snprintf(buf, sizeof(buf), "0x%x", z->flags[1]);
622 ptr.option = "__flags_v6";
628 write_ipset_uci(struct uci_context *ctx, struct fw3_ipset *s,
629 struct uci_package *dest)
631 struct fw3_ipset_datatype *type;
633 char buf[sizeof("65535-65535")];
635 struct uci_ptr ptr = { .p = dest };
637 if (!s->enabled || s->external)
640 uci_add_section(ctx, dest, "ipset", &ptr.s);
648 ptr.option = "family";
649 if (s->family == FW3_FAMILY_V4)
656 ptr.option = "storage";
657 ptr.value = fw3_ipset_method_names[s->method];
660 list_for_each_entry(type, &s->datatypes, list)
662 snprintf(buf, sizeof(buf), "%s_%s", type->dir, fw3_ipset_type_names[type->type]);
664 ptr.option = "match";
666 uci_add_list(ctx, &ptr);
672 ptr.option = "iprange";
673 ptr.value = fw3_address_to_string(&s->iprange, false, false);
677 if (s->portrange.set)
679 snprintf(buf, sizeof(buf), "%u-%u", s->portrange.port_min, s->portrange.port_max);
681 ptr.option = "portrange";
688 fw3_write_statefile(void *state)
691 struct fw3_state *s = state;
694 struct ifaddrs *ifaddr;
696 struct uci_package *p;
698 if (fw3_no_family(s->defaults.flags[0]) &&
699 fw3_no_family(s->defaults.flags[1]))
701 unlink(FW3_STATEFILE);
705 sf = fopen(FW3_STATEFILE, "w+");
709 warn("Cannot create state %s: %s", FW3_STATEFILE, strerror(errno));
713 if (getifaddrs(&ifaddr))
715 warn("Cannot get interface addresses: %s", strerror(errno));
719 if ((p = uci_lookup_package(s->uci, "fw3_state")) != NULL)
720 uci_unload(s->uci, p);
722 uci_import(s->uci, sf, "fw3_state", NULL, true);
724 if ((p = uci_lookup_package(s->uci, "fw3_state")) != NULL)
726 write_defaults_uci(s->uci, &s->defaults, p);
728 list_for_each_entry(z, &s->zones, list)
729 write_zone_uci(s->uci, z, p, ifaddr);
731 list_for_each_entry(i, &s->ipsets, list)
732 write_ipset_uci(s->uci, i, p);
734 uci_export(s->uci, sf, p, true);
735 uci_unload(s->uci, p);
748 fw3_free_object(void *obj, const void *opts)
750 const struct fw3_option *ol;
751 struct list_head *list, *cur, *tmp;
753 for (ol = opts; ol->name; ol++)
758 list = (struct list_head *)((char *)obj + ol->offset);
759 list_for_each_safe(cur, tmp, list)
770 fw3_free_list(struct list_head *head)
772 struct list_head *entry, *tmp;
777 list_for_each_safe(entry, tmp, head)
787 fw3_hotplug(bool add, void *zone, void *device)
789 struct fw3_zone *z = zone;
790 struct fw3_device *d = device;
798 warn("Unable to fork(): %s\n", strerror(errno));
814 setenv("ACTION", add ? "add" : "remove", 1);
815 setenv("ZONE", z->name, 1);
816 setenv("INTERFACE", d->network, 1);
817 setenv("DEVICE", d->name, 1);
819 execl(FW3_HOTPLUG, FW3_HOTPLUG, "firewall", NULL);
826 fw3_netmask2bitlen(int family, void *mask)
832 if (family == FW3_FAMILY_V6)
833 for (bits = 0, v6 = mask;
834 bits < 128 && (v6->s6_addr[bits / 8] << (bits % 8)) & 128;
837 for (bits = 0, v4 = mask;
838 bits < 32 && (ntohl(v4->s_addr) << bits) & 0x80000000;
845 fw3_bitlen2netmask(int family, int bits, void *mask)
852 if (family == FW3_FAMILY_V6)
854 if (bits < -128 || bits > 128)
860 for (i = 0; i < sizeof(v6->s6_addr); i++)
862 b = (rem > 8) ? 8 : rem;
863 v6->s6_addr[i] = (uint8_t)(0xFF << (8 - b));
868 for (i = 0; i < sizeof(v6->s6_addr); i++)
869 v6->s6_addr[i] = ~v6->s6_addr[i];
873 if (bits < -32 || bits > 32)
877 v4->s_addr = bits ? htonl(~((1 << (32 - abs(bits))) - 1)) : 0;
880 v4->s_addr = ~v4->s_addr;
887 fw3_flush_conntrack(void *state)
890 struct fw3_state *s = state;
891 struct fw3_address *addr;
892 struct fw3_device *dev;
893 struct fw3_zone *zone;
894 struct ifaddrs *ifaddr, *ifa;
895 struct sockaddr_in *sin;
896 struct sockaddr_in6 *sin6;
897 char buf[INET6_ADDRSTRLEN];
902 if ((ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
904 info(" * Flushing conntrack table ...");
906 fwrite("f\n", 1, 2, ct);
913 if (getifaddrs(&ifaddr))
915 warn("Cannot get interface addresses: %s", strerror(errno));
919 if ((ct = fopen("/proc/net/nf_conntrack", "w")) != NULL)
921 list_for_each_entry(zone, &s->zones, list)
922 list_for_each_entry(addr, &zone->old_addrs, list)
926 list_for_each_entry(dev, &zone->devices, list)
928 for (ifa = ifaddr; ifa && !found; ifa = ifa->ifa_next)
930 if (!ifa->ifa_addr || strcmp(dev->name, ifa->ifa_name))
933 sin = (struct sockaddr_in *)ifa->ifa_addr;
934 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
936 if (addr->family == FW3_FAMILY_V4 &&
937 sin->sin_family == AF_INET)
939 found = !memcmp(&addr->address.v4, &sin->sin_addr,
940 sizeof(sin->sin_addr));
942 else if (addr->family == FW3_FAMILY_V6 &&
943 sin6->sin6_family == AF_INET6)
945 found = !memcmp(&addr->address.v6, &sin6->sin6_addr,
946 sizeof(sin6->sin6_addr));
956 inet_ntop(addr->family == FW3_FAMILY_V4 ? AF_INET : AF_INET6,
957 &addr->address.v4, buf, sizeof(buf));
959 info(" * Flushing conntrack: %s", buf);
960 fprintf(ct, "%s\n", buf);
970 bool fw3_attr_parse_name_type(struct blob_attr *entry, const char **name, const char **type)
972 struct blob_attr *opt;
980 blobmsg_for_each_attr(opt, entry, orem)
981 if (!strcmp(blobmsg_name(opt), "type"))
982 *type = blobmsg_get_string(opt);
983 else if (!strcmp(blobmsg_name(opt), "name"))
984 *name = blobmsg_get_string(opt);
986 return *type != NULL ? true : false;
990 fw3_protoname(void *proto)
992 static char buf[sizeof("4294967295")];
993 struct fw3_protocol *p = proto;
999 pe = getprotobynumber(p->protocol);
1003 snprintf(buf, sizeof(buf), "%u", p->protocol);
1011 fw3_check_loopback_dev(const char *name)
1017 s = socket(AF_LOCAL, SOCK_DGRAM, 0);
1022 memset(&ifr, 0, sizeof(ifr));
1023 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", name);
1025 if (ioctl(s, SIOCGIFFLAGS, &ifr) >= 0) {
1026 if (ifr.ifr_flags & IFF_LOOPBACK)
1036 fw3_check_loopback_addr(struct fw3_address *addr)
1038 if (addr->family == FW3_FAMILY_V4 &&
1039 (ntohl(addr->address.v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
1042 if (addr->family == FW3_FAMILY_V6 && !addr->range &&
1043 fw3_netmask2bitlen(FW3_FAMILY_V6, &addr->mask.v6) == 128 &&
1044 IN6_IS_ADDR_LOOPBACK(&addr->address.v6))