| /* Library which manipulates firewall rules. Version 0.1. */ |
| |
| /* Architecture of firewall rules is as follows: |
| * |
| * Chains go INPUT, FORWARD, OUTPUT then user chains. |
| * Each user chain starts with an ERROR node. |
| * Every chain ends with an unconditional jump: a RETURN for user chains, |
| * and a POLICY for built-ins. |
| */ |
| |
| /* (C)1999 Paul ``Rusty'' Russell - Placed under the GNU GPL (See |
| COPYING for details). */ |
| |
| #include <assert.h> |
| #include <string.h> |
| #include <errno.h> |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <arpa/inet.h> |
| |
| #ifdef DEBUG_CONNTRACK |
| #define inline |
| #endif |
| |
| #if !defined(__BIONIC__) && (!defined(__GLIBC__) || (__GLIBC__ < 2)) |
| typedef unsigned int socklen_t; |
| #endif |
| |
| #include "libiptc/libip6tc.h" |
| |
| #define HOOK_PRE_ROUTING NF_IP6_PRE_ROUTING |
| #define HOOK_LOCAL_IN NF_IP6_LOCAL_IN |
| #define HOOK_FORWARD NF_IP6_FORWARD |
| #define HOOK_LOCAL_OUT NF_IP6_LOCAL_OUT |
| #define HOOK_POST_ROUTING NF_IP6_POST_ROUTING |
| |
| #define STRUCT_ENTRY_TARGET struct xt_entry_target |
| #define STRUCT_ENTRY struct ip6t_entry |
| #define STRUCT_ENTRY_MATCH struct xt_entry_match |
| #define STRUCT_GETINFO struct ip6t_getinfo |
| #define STRUCT_GET_ENTRIES struct ip6t_get_entries |
| #define STRUCT_COUNTERS struct xt_counters |
| #define STRUCT_COUNTERS_INFO struct xt_counters_info |
| #define STRUCT_STANDARD_TARGET struct xt_standard_target |
| #define STRUCT_REPLACE struct ip6t_replace |
| |
| #define ENTRY_ITERATE IP6T_ENTRY_ITERATE |
| #define TABLE_MAXNAMELEN XT_TABLE_MAXNAMELEN |
| #define FUNCTION_MAXNAMELEN XT_FUNCTION_MAXNAMELEN |
| |
| #define GET_TARGET ip6t_get_target |
| |
| #define ERROR_TARGET XT_ERROR_TARGET |
| #define NUMHOOKS NF_IP6_NUMHOOKS |
| |
| #define IPT_CHAINLABEL xt_chainlabel |
| |
| #define TC_DUMP_ENTRIES dump_entries6 |
| #define TC_IS_CHAIN ip6tc_is_chain |
| #define TC_FIRST_CHAIN ip6tc_first_chain |
| #define TC_NEXT_CHAIN ip6tc_next_chain |
| #define TC_FIRST_RULE ip6tc_first_rule |
| #define TC_NEXT_RULE ip6tc_next_rule |
| #define TC_GET_TARGET ip6tc_get_target |
| #define TC_BUILTIN ip6tc_builtin |
| #define TC_GET_POLICY ip6tc_get_policy |
| #define TC_INSERT_ENTRY ip6tc_insert_entry |
| #define TC_REPLACE_ENTRY ip6tc_replace_entry |
| #define TC_APPEND_ENTRY ip6tc_append_entry |
| #define TC_CHECK_ENTRY ip6tc_check_entry |
| #define TC_DELETE_ENTRY ip6tc_delete_entry |
| #define TC_DELETE_NUM_ENTRY ip6tc_delete_num_entry |
| #define TC_FLUSH_ENTRIES ip6tc_flush_entries |
| #define TC_ZERO_ENTRIES ip6tc_zero_entries |
| #define TC_ZERO_COUNTER ip6tc_zero_counter |
| #define TC_READ_COUNTER ip6tc_read_counter |
| #define TC_SET_COUNTER ip6tc_set_counter |
| #define TC_CREATE_CHAIN ip6tc_create_chain |
| #define TC_GET_REFERENCES ip6tc_get_references |
| #define TC_DELETE_CHAIN ip6tc_delete_chain |
| #define TC_RENAME_CHAIN ip6tc_rename_chain |
| #define TC_SET_POLICY ip6tc_set_policy |
| #define TC_GET_RAW_SOCKET ip6tc_get_raw_socket |
| #define TC_INIT ip6tc_init |
| #define TC_FREE ip6tc_free |
| #define TC_COMMIT ip6tc_commit |
| #define TC_STRERROR ip6tc_strerror |
| #define TC_NUM_RULES ip6tc_num_rules |
| #define TC_GET_RULE ip6tc_get_rule |
| #define TC_OPS ip6tc_ops |
| |
| #define TC_AF AF_INET6 |
| #define TC_IPPROTO IPPROTO_IPV6 |
| |
| #define SO_SET_REPLACE IP6T_SO_SET_REPLACE |
| #define SO_SET_ADD_COUNTERS IP6T_SO_SET_ADD_COUNTERS |
| #define SO_GET_INFO IP6T_SO_GET_INFO |
| #define SO_GET_ENTRIES IP6T_SO_GET_ENTRIES |
| #define SO_GET_VERSION IP6T_SO_GET_VERSION |
| |
| #define STANDARD_TARGET XT_STANDARD_TARGET |
| #define LABEL_RETURN IP6TC_LABEL_RETURN |
| #define LABEL_ACCEPT IP6TC_LABEL_ACCEPT |
| #define LABEL_DROP IP6TC_LABEL_DROP |
| #define LABEL_QUEUE IP6TC_LABEL_QUEUE |
| |
| #define ALIGN XT_ALIGN |
| #define RETURN XT_RETURN |
| |
| #include "libiptc.c" |
| |
| #define BIT6(a, l) \ |
| ((ntohl(a->s6_addr32[(l) / 32]) >> (31 - ((l) & 31))) & 1) |
| |
| static int |
| ipv6_prefix_length(const struct in6_addr *a) |
| { |
| int l, i; |
| for (l = 0; l < 128; l++) { |
| if (BIT6(a, l) == 0) |
| break; |
| } |
| for (i = l + 1; i < 128; i++) { |
| if (BIT6(a, i) == 1) |
| return -1; |
| } |
| return l; |
| } |
| |
| static int |
| dump_entry(struct ip6t_entry *e, struct xtc_handle *const handle) |
| { |
| size_t i; |
| char buf[40]; |
| int len; |
| struct xt_entry_target *t; |
| |
| printf("Entry %u (%lu):\n", iptcb_entry2index(handle, e), |
| iptcb_entry2offset(handle, e)); |
| puts("SRC IP: "); |
| inet_ntop(AF_INET6, &e->ipv6.src, buf, sizeof buf); |
| puts(buf); |
| putchar('/'); |
| len = ipv6_prefix_length(&e->ipv6.smsk); |
| if (len != -1) |
| printf("%d", len); |
| else { |
| inet_ntop(AF_INET6, &e->ipv6.smsk, buf, sizeof buf); |
| puts(buf); |
| } |
| putchar('\n'); |
| |
| puts("DST IP: "); |
| inet_ntop(AF_INET6, &e->ipv6.dst, buf, sizeof buf); |
| puts(buf); |
| putchar('/'); |
| len = ipv6_prefix_length(&e->ipv6.dmsk); |
| if (len != -1) |
| printf("%d", len); |
| else { |
| inet_ntop(AF_INET6, &e->ipv6.dmsk, buf, sizeof buf); |
| puts(buf); |
| } |
| putchar('\n'); |
| |
| printf("Interface: `%s'/", e->ipv6.iniface); |
| for (i = 0; i < IFNAMSIZ; i++) |
| printf("%c", e->ipv6.iniface_mask[i] ? 'X' : '.'); |
| printf("to `%s'/", e->ipv6.outiface); |
| for (i = 0; i < IFNAMSIZ; i++) |
| printf("%c", e->ipv6.outiface_mask[i] ? 'X' : '.'); |
| printf("\nProtocol: %u\n", e->ipv6.proto); |
| if (e->ipv6.flags & IP6T_F_TOS) |
| printf("TOS: %u\n", e->ipv6.tos); |
| printf("Flags: %02X\n", e->ipv6.flags); |
| printf("Invflags: %02X\n", e->ipv6.invflags); |
| printf("Counters: %llu packets, %llu bytes\n", |
| (unsigned long long)e->counters.pcnt, (unsigned long long)e->counters.bcnt); |
| printf("Cache: %08X\n", e->nfcache); |
| |
| IP6T_MATCH_ITERATE(e, print_match); |
| |
| t = ip6t_get_target(e); |
| printf("Target name: `%s' [%u]\n", t->u.user.name, t->u.target_size); |
| if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0) { |
| const unsigned char *data = t->data; |
| int pos = *(const int *)data; |
| if (pos < 0) |
| printf("verdict=%s\n", |
| pos == -NF_ACCEPT-1 ? "NF_ACCEPT" |
| : pos == -NF_DROP-1 ? "NF_DROP" |
| : pos == XT_RETURN ? "RETURN" |
| : "UNKNOWN"); |
| else |
| printf("verdict=%u\n", pos); |
| } else if (strcmp(t->u.user.name, XT_ERROR_TARGET) == 0) |
| printf("error=`%s'\n", t->data); |
| |
| printf("\n"); |
| return 0; |
| } |
| |
| static unsigned char * |
| is_same(const STRUCT_ENTRY *a, const STRUCT_ENTRY *b, |
| unsigned char *matchmask) |
| { |
| unsigned int i; |
| unsigned char *mptr; |
| |
| /* Always compare head structures: ignore mask here. */ |
| if (memcmp(&a->ipv6.src, &b->ipv6.src, sizeof(struct in6_addr)) |
| || memcmp(&a->ipv6.dst, &b->ipv6.dst, sizeof(struct in6_addr)) |
| || memcmp(&a->ipv6.smsk, &b->ipv6.smsk, sizeof(struct in6_addr)) |
| || memcmp(&a->ipv6.dmsk, &b->ipv6.dmsk, sizeof(struct in6_addr)) |
| || a->ipv6.proto != b->ipv6.proto |
| || a->ipv6.tos != b->ipv6.tos |
| || a->ipv6.flags != b->ipv6.flags |
| || a->ipv6.invflags != b->ipv6.invflags) |
| return NULL; |
| |
| for (i = 0; i < IFNAMSIZ; i++) { |
| if (a->ipv6.iniface_mask[i] != b->ipv6.iniface_mask[i]) |
| return NULL; |
| if ((a->ipv6.iniface[i] & a->ipv6.iniface_mask[i]) |
| != (b->ipv6.iniface[i] & b->ipv6.iniface_mask[i])) |
| return NULL; |
| if (a->ipv6.outiface_mask[i] != b->ipv6.outiface_mask[i]) |
| return NULL; |
| if ((a->ipv6.outiface[i] & a->ipv6.outiface_mask[i]) |
| != (b->ipv6.outiface[i] & b->ipv6.outiface_mask[i])) |
| return NULL; |
| } |
| |
| if (a->target_offset != b->target_offset |
| || a->next_offset != b->next_offset) |
| return NULL; |
| |
| mptr = matchmask + sizeof(STRUCT_ENTRY); |
| if (IP6T_MATCH_ITERATE(a, match_different, a->elems, b->elems, &mptr)) |
| return NULL; |
| mptr += XT_ALIGN(sizeof(struct xt_entry_target)); |
| |
| return mptr; |
| } |
| |
| #if 0 |
| /* All zeroes == unconditional rule. */ |
| static inline int |
| unconditional(const struct ip6t_ip6 *ipv6) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < sizeof(*ipv6); i++) |
| if (((char *)ipv6)[i]) |
| break; |
| |
| return (i == sizeof(*ipv6)); |
| } |
| #endif |