/* * (C) 2012 by Pablo Neira Ayuso * * 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. * * This code has been sponsored by Sophos Astaro */ #include #include #include #include #include #include #include /* getprotobynumber */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* inet_ntoa */ #include #include "nft.h" #include "xshared.h" /* proto_to_name */ #include "nft-shared.h" #include "xtables-config-parser.h" static void *nft_fn; static int mnl_talk(struct nft_handle *h, struct nlmsghdr *nlh, int (*cb)(const struct nlmsghdr *nlh, void *data), void *data) { int ret; char buf[MNL_SOCKET_BUFFER_SIZE]; if (mnl_socket_sendto(h->nl, nlh, nlh->nlmsg_len) < 0) { perror("mnl_socket_send"); return -1; } ret = mnl_socket_recvfrom(h->nl, buf, sizeof(buf)); while (ret > 0) { ret = mnl_cb_run(buf, ret, h->seq, h->portid, cb, data); if (ret <= 0) break; ret = mnl_socket_recvfrom(h->nl, buf, sizeof(buf)); } if (ret == -1) { return -1; } return 0; } struct builtin_table xtables_ipv4[TABLES_MAX] = { [RAW] = { .name = "raw", .chains = { { .name = "PREROUTING", .type = "filter", .prio = -300, /* NF_IP_PRI_RAW */ .hook = NF_INET_PRE_ROUTING, }, { .name = "OUTPUT", .type = "filter", .prio = -300, /* NF_IP_PRI_RAW */ .hook = NF_INET_LOCAL_OUT, }, }, }, [MANGLE] = { .name = "mangle", .chains = { { .name = "PREROUTING", .type = "filter", .prio = -150, /* NF_IP_PRI_MANGLE */ .hook = NF_INET_PRE_ROUTING, }, { .name = "INPUT", .type = "filter", .prio = -150, /* NF_IP_PRI_MANGLE */ .hook = NF_INET_LOCAL_IN, }, { .name = "FORWARD", .type = "filter", .prio = -150, /* NF_IP_PRI_MANGLE */ .hook = NF_INET_FORWARD, }, { .name = "OUTPUT", .type = "route", .prio = -150, /* NF_IP_PRI_MANGLE */ .hook = NF_INET_LOCAL_OUT, }, { .name = "POSTROUTING", .type = "filter", .prio = -150, /* NF_IP_PRI_MANGLE */ .hook = NF_INET_POST_ROUTING, }, }, }, [FILTER] = { .name = "filter", .chains = { { .name = "INPUT", .type = "filter", .prio = 0, /* NF_IP_PRI_FILTER */ .hook = NF_INET_LOCAL_IN, }, { .name = "FORWARD", .type = "filter", .prio = 0, /* NF_IP_PRI_FILTER */ .hook = NF_INET_FORWARD, }, { .name = "OUTPUT", .type = "filter", .prio = 0, /* NF_IP_PRI_FILTER */ .hook = NF_INET_LOCAL_OUT, }, }, }, [SECURITY] = { .name = "security", .chains = { { .name = "INPUT", .type = "filter", .prio = 150, /* NF_IP_PRI_SECURITY */ .hook = NF_INET_LOCAL_IN, }, { .name = "FORWARD", .type = "filter", .prio = 150, /* NF_IP_PRI_SECURITY */ .hook = NF_INET_FORWARD, }, { .name = "OUTPUT", .type = "filter", .prio = 150, /* NF_IP_PRI_SECURITY */ .hook = NF_INET_LOCAL_OUT, }, }, }, [NAT] = { .name = "nat", .chains = { { .name = "PREROUTING", .type = "nat", .prio = -100, /* NF_IP_PRI_NAT_DST */ .hook = NF_INET_PRE_ROUTING, }, { .name = "INPUT", .type = "nat", .prio = 100, /* NF_IP_PRI_NAT_SRC */ .hook = NF_INET_LOCAL_IN, }, { .name = "POSTROUTING", .type = "nat", .prio = 100, /* NF_IP_PRI_NAT_SRC */ .hook = NF_INET_POST_ROUTING, }, { .name = "OUTPUT", .type = "nat", .prio = -100, /* NF_IP_PRI_NAT_DST */ .hook = NF_INET_LOCAL_OUT, }, }, }, }; static int nft_table_builtin_add(struct nft_handle *h, struct builtin_table *_t, bool dormant) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_table *t; int ret; t = nft_table_alloc(); if (t == NULL) return -1; nft_table_attr_set(t, NFT_TABLE_ATTR_NAME, (char *)_t->name); if (dormant) { nft_table_attr_set_u32(t, NFT_TABLE_ATTR_FLAGS, NFT_TABLE_F_DORMANT); } nlh = nft_table_nlmsg_build_hdr(buf, NFT_MSG_NEWTABLE, h->family, NLM_F_ACK|NLM_F_EXCL, h->seq); nft_table_nlmsg_build_payload(nlh, t); nft_table_free(t); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) { if (errno != EEXIST) perror("mnl-talk:nft_table_init_one"); } return ret; } static struct nft_chain * nft_chain_builtin_alloc(struct builtin_table *table, struct builtin_chain *chain, int policy) { struct nft_chain *c; c = nft_chain_alloc(); if (c == NULL) return NULL; nft_chain_attr_set(c, NFT_CHAIN_ATTR_TABLE, (char *)table->name); nft_chain_attr_set(c, NFT_CHAIN_ATTR_NAME, (char *)chain->name); nft_chain_attr_set_u32(c, NFT_CHAIN_ATTR_HOOKNUM, chain->hook); nft_chain_attr_set_u32(c, NFT_CHAIN_ATTR_PRIO, chain->prio); nft_chain_attr_set_u32(c, NFT_CHAIN_ATTR_POLICY, policy); nft_chain_attr_set(c, NFT_CHAIN_ATTR_TYPE, (char *)chain->type); return c; } static void nft_chain_builtin_add(struct nft_handle *h, struct builtin_table *table, struct builtin_chain *chain, int policy) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_chain *c; c = nft_chain_builtin_alloc(table, chain, policy); if (c == NULL) return; /* NLM_F_CREATE requests module autoloading */ nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_NEWCHAIN, h->family, NLM_F_ACK|NLM_F_EXCL|NLM_F_CREATE, h->seq); nft_chain_nlmsg_build_payload(nlh, c); nft_chain_free(c); if (mnl_talk(h, nlh, NULL, NULL) < 0) { if (errno != EEXIST) perror("mnl_talk:nft_chain_builtin_add"); } } /* find if built-in table already exists */ static struct builtin_table *nft_table_builtin_find(struct nft_handle *h, const char *table) { int i; bool found = false; for (i=0; itables[i].name == NULL) break; if (strcmp(h->tables[i].name, table) != 0) continue; found = true; break; } return found ? &h->tables[i] : NULL; } /* find if built-in chain already exists */ static struct builtin_chain * nft_chain_builtin_find(struct builtin_table *t, const char *chain) { int i; bool found = false; for (i=0; ichains[i].name != NULL; i++) { if (strcmp(t->chains[i].name, chain) != 0) continue; found = true; break; } return found ? &t->chains[i] : NULL; } static void __nft_chain_builtin_init(struct nft_handle *h, struct builtin_table *table, const char *chain, int policy) { int i, default_policy; /* Initialize all built-in chains. Exception, for e one received as * parameter, set the default policy as requested. */ for (i=0; ichains[i].name != NULL; i++) { if (chain && strcmp(table->chains[i].name, chain) == 0) default_policy = policy; else default_policy = NF_ACCEPT; nft_chain_builtin_add(h, table, &table->chains[i], default_policy); } } static int nft_chain_builtin_init(struct nft_handle *h, const char *table, const char *chain, int policy) { int ret = 0; struct builtin_table *t; t = nft_table_builtin_find(h, table); if (t == NULL) { ret = -1; goto out; } if (nft_table_builtin_add(h, t, false) < 0) { /* Built-in table already initialized, skip. */ if (errno == EEXIST) goto out; } __nft_chain_builtin_init(h, t, chain, policy); out: return ret; } static bool nft_chain_builtin(struct nft_chain *c) { /* Check if this chain has hook number, in that case is built-in. * Should we better export the flags to user-space via nf_tables? */ return nft_chain_attr_get(c, NFT_CHAIN_ATTR_HOOKNUM) != NULL; } int nft_init(struct nft_handle *h, struct builtin_table *t) { h->nl = mnl_socket_open(NETLINK_NETFILTER); if (h->nl == NULL) { perror("mnl_socket_open"); return -1; } if (mnl_socket_bind(h->nl, 0, MNL_SOCKET_AUTOPID) < 0) { perror("mnl_socket_bind"); return -1; } h->portid = mnl_socket_get_portid(h->nl); h->tables = t; return 0; } void nft_fini(struct nft_handle *h) { mnl_socket_close(h->nl); } int nft_table_add(struct nft_handle *h, const struct nft_table *t) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; nlh = nft_table_nlmsg_build_hdr(buf, NFT_MSG_NEWTABLE, h->family, NLM_F_ACK|NLM_F_EXCL, h->seq); nft_table_nlmsg_build_payload(nlh, t); return mnl_talk(h, nlh, NULL, NULL); } int nft_chain_add(struct nft_handle *h, const struct nft_chain *c) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_NEWCHAIN, h->family, NLM_F_ACK|NLM_F_EXCL, h->seq); nft_chain_nlmsg_build_payload(nlh, c); return mnl_talk(h, nlh, NULL, NULL); } int nft_table_set_dormant(struct nft_handle *h, const char *table) { int ret = 0, i; struct builtin_table *t; t = nft_table_builtin_find(h, table); if (t == NULL) { ret = -1; goto out; } /* Add this table as dormant */ if (nft_table_builtin_add(h, t, true) < 0) { /* Built-in table already initialized, skip. */ if (errno == EEXIST) goto out; } for (i=0; t->chains[i].name != NULL && ichains[i].name, NF_ACCEPT); out: return ret; } int nft_table_wake_dormant(struct nft_handle *h, const char *table) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_table *t; t = nft_table_alloc(); if (t == NULL) return -1; nft_table_attr_set(t, NFT_TABLE_ATTR_NAME, (char *)table); nft_table_attr_set_u32(t, NFT_TABLE_ATTR_FLAGS, 0); nlh = nft_table_nlmsg_build_hdr(buf, NFT_MSG_NEWTABLE, h->family, NLM_F_ACK, h->seq); nft_table_nlmsg_build_payload(nlh, t); nft_table_free(t); return mnl_talk(h, nlh, NULL, NULL); } static void nft_chain_print_debug(struct nft_chain *c, struct nlmsghdr *nlh) { #ifdef NLDEBUG char tmp[1024]; nft_chain_snprintf(tmp, sizeof(tmp), c, 0, 0); printf("DEBUG: chain: %s", tmp); mnl_nlmsg_fprintf(stdout, nlh, nlh->nlmsg_len, sizeof(struct nfgenmsg)); #endif } static int __nft_chain_set(struct nft_handle *h, const char *table, const char *chain, int policy, const struct xt_counters *counters) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_chain *c; struct builtin_table *_t; struct builtin_chain *_c; int ret; _t = nft_table_builtin_find(h, table); /* if this built-in table does not exists, create it */ if (_t != NULL) nft_table_builtin_add(h, _t, false); _c = nft_chain_builtin_find(_t, chain); if (_c != NULL) { /* This is a built-in chain */ c = nft_chain_builtin_alloc(_t, _c, policy); if (c == NULL) return -1; } else { errno = ENOENT; return -1; } if (counters) { nft_chain_attr_set_u64(c, NFT_CHAIN_ATTR_BYTES, counters->bcnt); nft_chain_attr_set_u64(c, NFT_CHAIN_ATTR_PACKETS, counters->pcnt); } nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_NEWCHAIN, h->family, NLM_F_ACK, h->seq); nft_chain_nlmsg_build_payload(nlh, c); nft_chain_print_debug(c, nlh); nft_chain_free(c); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) perror("mnl_talk:__nft_chain_policy"); return ret; } int nft_chain_set(struct nft_handle *h, const char *table, const char *chain, const char *policy, const struct xt_counters *counters) { int ret = -1; nft_fn = nft_chain_set; if (strcmp(policy, "DROP") == 0) ret = __nft_chain_set(h, table, chain, NF_DROP, counters); else if (strcmp(policy, "ACCEPT") == 0) ret = __nft_chain_set(h, table, chain, NF_ACCEPT, counters); /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } static int __add_match(struct nft_rule_expr *e, struct xt_entry_match *m) { void *info; nft_rule_expr_set(e, NFT_EXPR_MT_NAME, m->u.user.name, strlen(m->u.user.name)); nft_rule_expr_set_u32(e, NFT_EXPR_MT_REV, m->u.user.revision); info = calloc(1, m->u.match_size); if (info == NULL) return -ENOMEM; memcpy(info, m->data, m->u.match_size); nft_rule_expr_set(e, NFT_EXPR_MT_INFO, info, m->u.match_size - sizeof(*m)); return 0; } static int add_match(struct nft_rule *r, struct xt_entry_match *m) { struct nft_rule_expr *expr; int ret; expr = nft_rule_expr_alloc("match"); if (expr == NULL) return -ENOMEM; ret = __add_match(expr, m); nft_rule_add_expr(r, expr); return ret; } static int __add_target(struct nft_rule_expr *e, struct xt_entry_target *t) { void *info = NULL; nft_rule_expr_set(e, NFT_EXPR_TG_NAME, t->u.user.name, strlen(t->u.user.name)); nft_rule_expr_set_u32(e, NFT_EXPR_TG_REV, t->u.user.revision); if (info == NULL) { info = calloc(1, t->u.target_size); if (info == NULL) return -ENOMEM; memcpy(info, t->data, t->u.target_size); } nft_rule_expr_set(e, NFT_EXPR_TG_INFO, info, t->u.target_size - sizeof(*t)); return 0; } static int add_target(struct nft_rule *r, struct xt_entry_target *t) { struct nft_rule_expr *expr; int ret; expr = nft_rule_expr_alloc("target"); if (expr == NULL) return -ENOMEM; ret = __add_target(expr, t); nft_rule_add_expr(r, expr); return ret; } static int add_jumpto(struct nft_rule *r, const char *name, int verdict) { struct nft_rule_expr *expr; expr = nft_rule_expr_alloc("immediate"); if (expr == NULL) return -ENOMEM; nft_rule_expr_set_u32(expr, NFT_EXPR_IMM_DREG, NFT_REG_VERDICT); nft_rule_expr_set_u32(expr, NFT_EXPR_IMM_VERDICT, verdict); nft_rule_expr_set_str(expr, NFT_EXPR_IMM_CHAIN, (char *)name); nft_rule_add_expr(r, expr); return 0; } static int add_verdict(struct nft_rule *r, int verdict) { struct nft_rule_expr *expr; expr = nft_rule_expr_alloc("immediate"); if (expr == NULL) return -ENOMEM; nft_rule_expr_set_u32(expr, NFT_EXPR_IMM_DREG, NFT_REG_VERDICT); nft_rule_expr_set_u32(expr, NFT_EXPR_IMM_VERDICT, verdict); nft_rule_add_expr(r, expr); return 0; } static void nft_rule_print_debug(struct nft_rule *r, struct nlmsghdr *nlh) { #ifdef NLDEBUG char tmp[1024]; nft_rule_snprintf(tmp, sizeof(tmp), r, 0, 0); printf("DEBUG: rule: %s", tmp); mnl_nlmsg_fprintf(stdout, nlh, nlh->nlmsg_len, sizeof(struct nfgenmsg)); #endif } static int add_counters(struct nft_rule *r, uint64_t packets, uint64_t bytes) { struct nft_rule_expr *expr; expr = nft_rule_expr_alloc("counter"); if (expr == NULL) return -ENOMEM; nft_rule_expr_set_u64(expr, NFT_EXPR_CTR_BYTES, packets); nft_rule_expr_set_u64(expr, NFT_EXPR_CTR_PACKETS, bytes); nft_rule_add_expr(r, expr); return 0; } void add_compat(struct nft_rule *r, uint32_t proto, bool inv) { nft_rule_attr_set_u32(r, NFT_RULE_ATTR_COMPAT_PROTO, proto); nft_rule_attr_set_u32(r, NFT_RULE_ATTR_COMPAT_FLAGS, inv ? NFT_RULE_COMPAT_F_INV : 0); } static struct nft_rule * nft_rule_new(struct nft_handle *h, const char *chain, const char *table, struct iptables_command_state *cs) { struct nft_rule *r; int ret = 0, ip_flags = 0; struct xtables_rule_match *matchp; r = nft_rule_alloc(); if (r == NULL) return NULL; nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FAMILY, h->family); nft_rule_attr_set(r, NFT_RULE_ATTR_TABLE, (char *)table); nft_rule_attr_set(r, NFT_RULE_ATTR_CHAIN, (char *)chain); ip_flags = h->ops->add(r, cs); for (matchp = cs->matches; matchp; matchp = matchp->next) { if (add_match(r, matchp->match->m) < 0) goto err; } /* Counters need to me added before the target, otherwise they are * increased for each rule because of the way nf_tables works. */ if (add_counters(r, cs->counters.pcnt, cs->counters.bcnt) < 0) goto err; /* If no target at all, add nothing (default to continue) */ if (cs->target != NULL) { /* Standard target? */ if (strcmp(cs->jumpto, XTC_LABEL_ACCEPT) == 0) ret = add_verdict(r, NF_ACCEPT); else if (strcmp(cs->jumpto, XTC_LABEL_DROP) == 0) ret = add_verdict(r, NF_DROP); else if (strcmp(cs->jumpto, XTC_LABEL_RETURN) == 0) ret = add_verdict(r, NFT_RETURN); else ret = add_target(r, cs->target->t); } else if (strlen(cs->jumpto) > 0) { /* Not standard, then it's a go / jump to chain */ if (ip_flags & IPT_F_GOTO) ret = add_jumpto(r, cs->jumpto, NFT_GOTO); else ret = add_jumpto(r, cs->jumpto, NFT_JUMP); } if (ret < 0) goto err; return r; err: nft_rule_free(r); return NULL; } int nft_rule_append(struct nft_handle *h, const char *chain, const char *table, struct iptables_command_state *cs, uint64_t handle, bool verbose) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_rule *r; uint16_t flags = NLM_F_ACK|NLM_F_CREATE; int ret = 1; /* If built-in chains don't exist for this table, create them */ if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0) nft_chain_builtin_init(h, table, chain, NF_ACCEPT); nft_fn = nft_rule_append; r = nft_rule_new(h, chain, table, cs); if (r == NULL) { ret = 0; goto err; } if (handle > 0) { nft_rule_attr_set(r, NFT_RULE_ATTR_HANDLE, &handle); flags |= NLM_F_REPLACE; } else flags |= NLM_F_APPEND; if (h->commit) { nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FLAGS, NFT_RULE_F_COMMIT); } nlh = nft_rule_nlmsg_build_hdr(buf, NFT_MSG_NEWRULE, h->family, flags, h->seq); nft_rule_nlmsg_build_payload(nlh, r); nft_rule_print_debug(r, nlh); nft_rule_free(r); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) perror("mnl_talk:nft_rule_append"); err: /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } void nft_rule_print_save(const struct iptables_command_state *cs, struct nft_rule *r, enum nft_rule_print type, unsigned int format) { const char *chain = nft_rule_attr_get_str(r, NFT_RULE_ATTR_CHAIN); int family = nft_rule_attr_get_u8(r, NFT_RULE_ATTR_FAMILY); struct xtables_rule_match *matchp; struct nft_family_ops *ops; int ip_flags = 0; /* print chain name */ switch(type) { case NFT_RULE_APPEND: printf("-A %s ", chain); break; case NFT_RULE_DEL: printf("-D %s ", chain); break; } ops = nft_family_ops_lookup(family); ip_flags = ops->save_firewall(cs, format); for (matchp = cs->matches; matchp; matchp = matchp->next) { if (matchp->match->alias) { printf("-m %s", matchp->match->alias(matchp->match->m)); } else printf("-m %s", matchp->match->name); if (matchp->match->save != NULL) matchp->match->save(NULL, matchp->match->m); printf(" "); } if (cs->target != NULL) { if (cs->target->alias) { printf("-j %s", cs->target->alias(cs->target->t)); } else printf("-j %s", cs->jumpto); if (cs->target->save != NULL) cs->target->save(NULL, cs->target->t); } else if (strlen(cs->jumpto) > 0) printf("-%c %s", ip_flags & IPT_F_GOTO ? 'g' : 'j', cs->jumpto); printf("\n"); } static int nft_chain_list_cb(const struct nlmsghdr *nlh, void *data) { struct nft_chain *c; struct nft_chain_list *list = data; c = nft_chain_alloc(); if (c == NULL) { perror("OOM"); goto err; } if (nft_chain_nlmsg_parse(nlh, c) < 0) { perror("nft_rule_nlmsg_parse"); goto out; } nft_chain_list_add_tail(c, list); return MNL_CB_OK; out: nft_chain_free(c); err: return MNL_CB_OK; } static struct nft_chain_list *nft_chain_list_get(struct nft_handle *h) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; int ret; struct nft_chain_list *list; list = nft_chain_list_alloc(); if (list == NULL) { errno = ENOMEM; return NULL; } nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_GETCHAIN, h->family, NLM_F_DUMP, h->seq); ret = mnl_talk(h, nlh, nft_chain_list_cb, list); if (ret < 0) perror("mnl_talk:nft_chain_list_get"); return list; } struct nft_chain_list *nft_chain_dump(struct nft_handle *h) { return nft_chain_list_get(h); } static const char *policy_name[NF_ACCEPT+1] = { [NF_DROP] = "DROP", [NF_ACCEPT] = "ACCEPT", }; static void nft_chain_print_save(struct nft_chain *c, bool basechain) { const char *chain = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_NAME); uint64_t pkts = nft_chain_attr_get_u64(c, NFT_CHAIN_ATTR_PACKETS); uint64_t bytes = nft_chain_attr_get_u64(c, NFT_CHAIN_ATTR_BYTES); /* print chain name */ if (basechain) { uint32_t pol = NF_ACCEPT; /* no default chain policy? don't crash, display accept */ if (nft_chain_attr_get(c, NFT_CHAIN_ATTR_POLICY)) pol = nft_chain_attr_get_u32(c, NFT_CHAIN_ATTR_POLICY); printf(":%s %s [%"PRIu64":%"PRIu64"]\n", chain, policy_name[pol], pkts, bytes); } else printf(":%s - [%"PRIu64":%"PRIu64"]\n", chain, pkts, bytes); } int nft_chain_save(struct nft_handle *h, struct nft_chain_list *list, const char *table) { struct nft_chain_list_iter *iter; struct nft_chain *c; iter = nft_chain_list_iter_create(list); if (iter == NULL) return 0; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *chain_table = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_TABLE); bool basechain = false; if (strcmp(table, chain_table) != 0) goto next; basechain = nft_chain_builtin(c); nft_chain_print_save(c, basechain); next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); nft_chain_list_free(list); return 1; } static int nft_rule_list_cb(const struct nlmsghdr *nlh, void *data) { struct nft_rule *r; struct nft_rule_list *list = data; r = nft_rule_alloc(); if (r == NULL) { perror("OOM"); goto err; } if (nft_rule_nlmsg_parse(nlh, r) < 0) { perror("nft_rule_nlmsg_parse"); goto out; } nft_rule_list_add_tail(r, list); return MNL_CB_OK; out: nft_rule_free(r); nft_rule_list_free(list); err: return MNL_CB_OK; } static struct nft_rule_list *nft_rule_list_get(struct nft_handle *h) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_rule_list *list; int ret; list = nft_rule_list_alloc(); if (list == NULL) return 0; nlh = nft_rule_nlmsg_build_hdr(buf, NFT_MSG_GETRULE, h->family, NLM_F_DUMP, h->seq); ret = mnl_talk(h, nlh, nft_rule_list_cb, list); if (ret < 0) { perror("mnl_talk:nft_rule_save"); nft_rule_list_free(list); return NULL; } return list; } int nft_rule_save(struct nft_handle *h, const char *table, bool counters) { struct nft_rule_list *list; struct nft_rule_list_iter *iter; struct nft_rule *r; list = nft_rule_list_get(h); if (list == NULL) return 0; iter = nft_rule_list_iter_create(list); if (iter == NULL) return 0; r = nft_rule_list_iter_next(iter); while (r != NULL) { const char *rule_table = nft_rule_attr_get_str(r, NFT_RULE_ATTR_TABLE); struct iptables_command_state cs = {}; if (strcmp(table, rule_table) != 0) goto next; nft_rule_to_iptables_command_state(r, &cs); nft_rule_print_save(&cs, r, NFT_RULE_APPEND, counters ? 0 : FMT_NOCOUNTS); next: r = nft_rule_list_iter_next(iter); } nft_rule_list_iter_destroy(iter); nft_rule_list_free(list); /* the core expects 1 for success and 0 for error */ return 1; } static void __nft_rule_flush(struct nft_handle *h, const char *table, const char *chain) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_rule *r; r = nft_rule_alloc(); if (r == NULL) return; nft_rule_attr_set(r, NFT_RULE_ATTR_TABLE, (char *)table); nft_rule_attr_set(r, NFT_RULE_ATTR_CHAIN, (char *)chain); if (h->commit) { nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FLAGS, NFT_RULE_F_COMMIT); } /* Delete all rules in this table + chain */ nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_DELRULE, h->family, NLM_F_ACK, h->seq); nft_rule_nlmsg_build_payload(nlh, r); nft_rule_free(r); if (mnl_talk(h, nlh, NULL, NULL) < 0) { if (errno != EEXIST) perror("mnl_talk:__nft_rule_flush"); } } int nft_rule_flush(struct nft_handle *h, const char *chain, const char *table) { int ret; struct nft_chain_list *list; struct nft_chain_list_iter *iter; struct nft_chain *c; nft_fn = nft_rule_flush; list = nft_chain_list_get(h); if (list == NULL) { ret = 0; goto err; } iter = nft_chain_list_iter_create(list); if (iter == NULL) goto err; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *table_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_TABLE); const char *chain_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_NAME); if (strcmp(table, table_name) != 0) goto next; if (chain != NULL && strcmp(chain, chain_name) != 0) goto next; __nft_rule_flush(h, table_name, chain_name); if (chain != NULL) break; next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); err: nft_chain_list_free(list); /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } int nft_chain_user_add(struct nft_handle *h, const char *chain, const char *table) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_chain *c; int ret; /* If built-in chains don't exist for this table, create them */ if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0) nft_chain_builtin_init(h, table, NULL, NF_ACCEPT); c = nft_chain_alloc(); if (c == NULL) return 0; nft_chain_attr_set(c, NFT_CHAIN_ATTR_TABLE, (char *)table); nft_chain_attr_set(c, NFT_CHAIN_ATTR_NAME, (char *)chain); nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_NEWCHAIN, h->family, NLM_F_ACK|NLM_F_EXCL, h->seq); nft_chain_nlmsg_build_payload(nlh, c); nft_chain_free(c); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) { if (errno != EEXIST) perror("mnl_talk:nft_chain_add"); } /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } static int __nft_chain_del(struct nft_handle *h, struct nft_chain *c) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; int ret; nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_DELCHAIN, h->family, NLM_F_ACK, h->seq); nft_chain_nlmsg_build_payload(nlh, c); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) { if (errno != EEXIST && errno != ENOENT) perror("mnl_talk:__nft_chain_del"); } return ret; } int nft_chain_user_del(struct nft_handle *h, const char *chain, const char *table) { struct nft_chain_list *list; struct nft_chain_list_iter *iter; struct nft_chain *c; int ret = 0; int deleted_ctr = 0; list = nft_chain_list_get(h); if (list == NULL) goto err; iter = nft_chain_list_iter_create(list); if (iter == NULL) goto err; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *table_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_TABLE); const char *chain_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_NAME); /* don't delete built-in chain */ if (nft_chain_builtin(c)) goto next; if (strcmp(table, table_name) != 0) goto next; if (chain != NULL && strcmp(chain, chain_name) != 0) goto next; ret = __nft_chain_del(h, c); if (ret < 0) break; deleted_ctr++; if (chain != NULL) break; next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); err: nft_chain_list_free(list); /* chain not found */ if (ret < 0 && deleted_ctr == 0) errno = ENOENT; /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } struct nft_chain * nft_chain_list_find(struct nft_chain_list *list, const char *table, const char *chain) { struct nft_chain_list_iter *iter; struct nft_chain *c; iter = nft_chain_list_iter_create(list); if (iter == NULL) return NULL; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *table_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_TABLE); const char *chain_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_NAME); if (strcmp(table, table_name) != 0) goto next; if (strcmp(chain, chain_name) != 0) goto next; nft_chain_list_iter_destroy(iter); return c; next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); return NULL; } static struct nft_chain * nft_chain_find(struct nft_handle *h, const char *table, const char *chain) { struct nft_chain_list *list; list = nft_chain_list_get(h); if (list == NULL) return NULL; return nft_chain_list_find(list, table, chain); } int nft_chain_user_rename(struct nft_handle *h,const char *chain, const char *table, const char *newname) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_chain *c; uint64_t handle; int ret; /* If built-in chains don't exist for this table, create them */ if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0) nft_chain_builtin_init(h, table, NULL, NF_ACCEPT); /* Find the old chain to be renamed */ c = nft_chain_find(h, table, chain); if (c == NULL) { errno = ENOENT; return -1; } handle = nft_chain_attr_get_u64(c, NFT_CHAIN_ATTR_HANDLE); /* Now prepare the new name for the chain */ c = nft_chain_alloc(); if (c == NULL) return -1; nft_chain_attr_set(c, NFT_CHAIN_ATTR_TABLE, (char *)table); nft_chain_attr_set(c, NFT_CHAIN_ATTR_NAME, (char *)newname); nft_chain_attr_set_u64(c, NFT_CHAIN_ATTR_HANDLE, handle); nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_NEWCHAIN, h->family, NLM_F_ACK, h->seq); nft_chain_nlmsg_build_payload(nlh, c); nft_chain_free(c); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) { if (errno != EEXIST) perror("mnl_talk:nft_chain_rename"); } /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } static int nft_table_list_cb(const struct nlmsghdr *nlh, void *data) { struct nft_table *t; struct nft_table_list *list = data; t = nft_table_alloc(); if (t == NULL) { perror("OOM"); goto err; } if (nft_table_nlmsg_parse(nlh, t) < 0) { perror("nft_rule_nlmsg_parse"); goto out; } nft_table_list_add_tail(t, list); return MNL_CB_OK; out: nft_table_free(t); err: return MNL_CB_OK; } static struct nft_table_list *nft_table_list_get(struct nft_handle *h) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; int ret; struct nft_table_list *list; list = nft_table_list_alloc(); if (list == NULL) return 0; nlh = nft_rule_nlmsg_build_hdr(buf, NFT_MSG_GETTABLE, h->family, NLM_F_DUMP, h->seq); ret = mnl_talk(h, nlh, nft_table_list_cb, list); if (ret < 0) perror("mnl_talk:nft_table_list_get"); return list; } bool nft_table_find(struct nft_handle *h, const char *tablename) { struct nft_table_list *list; struct nft_table_list_iter *iter; struct nft_table *t; bool ret = false; list = nft_table_list_get(h); if (list == NULL) goto err; iter = nft_table_list_iter_create(list); if (iter == NULL) goto err; t = nft_table_list_iter_next(iter); while (t != NULL) { const char *this_tablename = nft_table_attr_get(t, NFT_TABLE_ATTR_NAME); if (strcmp(tablename, this_tablename) == 0) return true; t = nft_table_list_iter_next(iter); } nft_table_list_free(list); err: return ret; } int nft_for_each_table(struct nft_handle *h, int (*func)(struct nft_handle *h, const char *tablename, bool counters), bool counters) { int ret = 1; struct nft_table_list *list; struct nft_table_list_iter *iter; struct nft_table *t; list = nft_table_list_get(h); if (list == NULL) { ret = 0; goto err; } iter = nft_table_list_iter_create(list); if (iter == NULL) return 0; t = nft_table_list_iter_next(iter); while (t != NULL) { const char *tablename = nft_table_attr_get(t, NFT_TABLE_ATTR_NAME); func(h, tablename, counters); t = nft_table_list_iter_next(iter); } nft_table_list_free(list); err: /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } int nft_table_purge_chains(struct nft_handle *h, const char *this_table, struct nft_chain_list *chain_list) { struct nft_chain_list_iter *iter; struct nft_chain *chain_obj; iter = nft_chain_list_iter_create(chain_list); if (iter == NULL) return 0; chain_obj = nft_chain_list_iter_next(iter); while (chain_obj != NULL) { const char *table = nft_chain_attr_get_str(chain_obj, NFT_CHAIN_ATTR_TABLE); if (strcmp(this_table, table) != 0) goto next; if (nft_chain_builtin(chain_obj)) goto next; if ( __nft_chain_del(h, chain_obj) < 0) { if (errno != EBUSY) return -1; } next: chain_obj = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); return 0; } static bool compare_matches(struct xtables_rule_match *mt1, struct xtables_rule_match *mt2) { struct xtables_rule_match *mp1; struct xtables_rule_match *mp2; for (mp1 = mt1, mp2 = mt2; mp1 && mp2; mp1 = mp1->next, mp2 = mp2->next) { struct xt_entry_match *m1 = mp1->match->m; struct xt_entry_match *m2 = mp2->match->m; if (strcmp(m1->u.user.name, m2->u.user.name) != 0) { DEBUGP("mismatching match name\n"); return false; } if (m1->u.user.match_size != m2->u.user.match_size) { DEBUGP("mismatching match size\n"); return false; } if (memcmp(m1->data, m2->data, m1->u.user.match_size - sizeof(*m1)) != 0) { DEBUGP("mismatch match data\n"); return false; } } /* Both cursors should be NULL */ if (mp1 != mp2) { DEBUGP("mismatch matches amount\n"); return false; } return true; } static bool compare_targets(struct xtables_target *tg1, struct xtables_target *tg2) { if (tg1 == NULL && tg2 == NULL) return true; if ((tg1 == NULL && tg2 != NULL) || (tg1 != NULL && tg2 == NULL)) return false; if (strcmp(tg1->t->u.user.name, tg2->t->u.user.name) != 0) return false; if (memcmp(tg1->t->data, tg2->t->data, tg1->t->u.user.target_size - sizeof(*tg1->t)) != 0) { return false; } return true; } static void __nft_rule_del(struct nft_handle *h, struct nft_rule *r) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; int ret; nlh = nft_rule_nlmsg_build_hdr(buf, NFT_MSG_DELRULE, h->family, NLM_F_ACK, h->seq); nft_rule_nlmsg_build_payload(nlh, r); nft_rule_print_debug(r, nlh); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) perror("mnl_talk:nft_rule_del"); } static struct nft_rule_list *nft_rule_list_create(struct nft_handle *h) { return nft_rule_list_get(h); } static void nft_rule_list_destroy(struct nft_rule_list *list) { nft_rule_list_free(list); } static struct nft_rule * nft_rule_find(struct nft_rule_list *list, const char *chain, const char *table, struct iptables_command_state *cs, int rulenum) { struct nft_rule *r; struct nft_rule_list_iter *iter; int rule_ctr = 0; bool found = false; iter = nft_rule_list_iter_create(list); if (iter == NULL) return 0; r = nft_rule_list_iter_next(iter); while (r != NULL) { const char *rule_table = nft_rule_attr_get_str(r, NFT_RULE_ATTR_TABLE); const char *rule_chain = nft_rule_attr_get_str(r, NFT_RULE_ATTR_CHAIN); const struct nft_family_ops *ops = nft_family_ops_lookup( nft_rule_attr_get_u8(r, NFT_RULE_ATTR_FAMILY)); struct iptables_command_state this = {}; if (strcmp(table, rule_table) != 0 || strcmp(chain, rule_chain) != 0) { DEBUGP("different chain / table\n"); goto next; } if (rulenum >= 0) { /* Delete by rule number case */ if (rule_ctr != rulenum) goto next; found = true; break; } else { /* Delete by matching rule case */ nft_rule_to_iptables_command_state(r, &this); DEBUGP("comparing with... "); #ifdef DEBUG_DEL nft_rule_print_save(&this, r, NFT_RULE_APPEND, 0); #endif if (!ops->is_same(cs, &this)) goto next; if (!compare_matches(cs->matches, this.matches)) { DEBUGP("Different matches\n"); goto next; } if (!compare_targets(cs->target, this.target)) { DEBUGP("Different target\n"); goto next; } if (strcmp(cs->jumpto, this.jumpto) != 0) { DEBUGP("Different verdict\n"); goto next; } found = true; break; } next: rule_ctr++; r = nft_rule_list_iter_next(iter); } nft_rule_list_iter_destroy(iter); return found ? r : NULL; } int nft_rule_check(struct nft_handle *h, const char *chain, const char *table, struct iptables_command_state *e, bool verbose) { struct nft_rule_list *list; int ret; nft_fn = nft_rule_check; list = nft_rule_list_create(h); if (list == NULL) return 0; ret = nft_rule_find(list, chain, table, e, -1) ? 1 : 0; if (ret == 0) errno = ENOENT; nft_rule_list_destroy(list); return ret; } int nft_rule_delete(struct nft_handle *h, const char *chain, const char *table, struct iptables_command_state *cs, bool verbose) { int ret = 0; struct nft_rule *r; struct nft_rule_list *list; nft_fn = nft_rule_delete; list = nft_rule_list_create(h); if (list == NULL) return 0; r = nft_rule_find(list, chain, table, cs, -1); if (r != NULL) { ret = 1; if (h->commit) { nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FLAGS, NFT_RULE_F_COMMIT); } DEBUGP("deleting rule\n"); __nft_rule_del(h, r); } else errno = ENOENT; nft_rule_list_destroy(list); return ret; } static int nft_rule_add(struct nft_handle *h, const char *chain, const char *table, struct iptables_command_state *cs, uint64_t handle, bool verbose) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; struct nft_rule *r; int ret = 1; r = nft_rule_new(h, chain, table, cs); if (r == NULL) { ret = 0; goto err; } if (handle > 0) nft_rule_attr_set_u64(r, NFT_RULE_ATTR_POSITION, handle); if (h->commit) { nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FLAGS, NFT_RULE_F_COMMIT); } nlh = nft_rule_nlmsg_build_hdr(buf, NFT_MSG_NEWRULE, h->family, NLM_F_ACK|NLM_F_CREATE, h->seq); nft_rule_nlmsg_build_payload(nlh, r); nft_rule_print_debug(r, nlh); nft_rule_free(r); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) perror("mnl_talk:nft_rule_add_num"); err: /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; } int nft_rule_insert(struct nft_handle *h, const char *chain, const char *table, struct iptables_command_state *cs, int rulenum, bool verbose) { struct nft_rule_list *list; struct nft_rule *r; uint64_t handle = 0; /* If built-in chains don't exist for this table, create them */ if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0) nft_chain_builtin_init(h, table, chain, NF_ACCEPT); nft_fn = nft_rule_insert; if (rulenum > 0) { list = nft_rule_list_create(h); if (list == NULL) goto err; r = nft_rule_find(list, chain, table, cs, rulenum); if (r == NULL) { errno = ENOENT; goto err; } handle = nft_rule_attr_get_u64(r, NFT_RULE_ATTR_HANDLE); DEBUGP("adding after rule handle %"PRIu64"\n", handle); nft_rule_list_destroy(list); } return nft_rule_add(h, chain, table, cs, handle, verbose); err: nft_rule_list_destroy(list); return 0; } int nft_rule_delete_num(struct nft_handle *h, const char *chain, const char *table, int rulenum, bool verbose) { int ret = 0; struct nft_rule *r; struct nft_rule_list *list; nft_fn = nft_rule_delete_num; list = nft_rule_list_create(h); if (list == NULL) return 0; r = nft_rule_find(list, chain, table, NULL, rulenum); if (r != NULL) { ret = 1; if (h->commit) { nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FLAGS, NFT_RULE_F_COMMIT); } DEBUGP("deleting rule by number %d\n", rulenum); __nft_rule_del(h, r); } else errno = ENOENT; nft_rule_list_destroy(list); return ret; } int nft_rule_replace(struct nft_handle *h, const char *chain, const char *table, struct iptables_command_state *cs, int rulenum, bool verbose) { int ret = 0; struct nft_rule *r; struct nft_rule_list *list; nft_fn = nft_rule_replace; list = nft_rule_list_create(h); if (list == NULL) return 0; r = nft_rule_find(list, chain, table, cs, rulenum); if (r != NULL) { DEBUGP("replacing rule with handle=%llu\n", (unsigned long long) nft_rule_attr_get_u64(r, NFT_RULE_ATTR_HANDLE)); if (h->commit) { nft_rule_attr_set_u32(r, NFT_RULE_ATTR_FLAGS, NFT_RULE_F_COMMIT); } ret = nft_rule_append(h, chain, table, cs, nft_rule_attr_get_u64(r, NFT_RULE_ATTR_HANDLE), verbose); } else errno = ENOENT; nft_rule_list_destroy(list); return ret; } static void print_header(unsigned int format, const char *chain, const char *pol, const struct xt_counters *counters, bool basechain, uint32_t refs) { printf("Chain %s", chain); if (basechain) { printf(" (policy %s", pol); if (!(format & FMT_NOCOUNTS)) { fputc(' ', stdout); xtables_print_num(counters->pcnt, (format|FMT_NOTABLE)); fputs("packets, ", stdout); xtables_print_num(counters->bcnt, (format|FMT_NOTABLE)); fputs("bytes", stdout); } printf(")\n"); } else { printf(" (%u references)\n", refs); } if (format & FMT_LINENUMBERS) printf(FMT("%-4s ", "%s "), "num"); if (!(format & FMT_NOCOUNTS)) { if (format & FMT_KILOMEGAGIGA) { printf(FMT("%5s ","%s "), "pkts"); printf(FMT("%5s ","%s "), "bytes"); } else { printf(FMT("%8s ","%s "), "pkts"); printf(FMT("%10s ","%s "), "bytes"); } } if (!(format & FMT_NOTARGET)) printf(FMT("%-9s ","%s "), "target"); fputs(" prot ", stdout); if (format & FMT_OPTIONS) fputs("opt", stdout); if (format & FMT_VIA) { printf(FMT(" %-6s ","%s "), "in"); printf(FMT("%-6s ","%s "), "out"); } printf(FMT(" %-19s ","%s "), "source"); printf(FMT(" %-19s "," %s "), "destination"); printf("\n"); } static int __nft_rule_list(struct nft_handle *h, const char *chain, const char *table, int rulenum, unsigned int format, void (*cb)(struct nft_rule *r, unsigned int num, unsigned int format)) { struct nft_rule_list *list; struct nft_rule_list_iter *iter; struct nft_rule *r; int rule_ctr = 0, ret = 0; list = nft_rule_list_get(h); if (list == NULL) return 0; iter = nft_rule_list_iter_create(list); if (iter == NULL) goto err; r = nft_rule_list_iter_next(iter); while (r != NULL) { const char *rule_table = nft_rule_attr_get_str(r, NFT_RULE_ATTR_TABLE); const char *rule_chain = nft_rule_attr_get_str(r, NFT_RULE_ATTR_CHAIN); rule_ctr++; if (strcmp(table, rule_table) != 0 || strcmp(chain, rule_chain) != 0) goto next; if (rulenum > 0 && rule_ctr != rulenum) { /* List by rule number case */ goto next; } cb(r, rule_ctr, format); if (rulenum > 0 && rule_ctr == rulenum) { ret = 1; break; } next: r = nft_rule_list_iter_next(iter); } nft_rule_list_iter_destroy(iter); err: nft_rule_list_free(list); if (ret == 0) errno = ENOENT; return ret; } int nft_rule_list(struct nft_handle *h, const char *chain, const char *table, int rulenum, unsigned int format) { const struct nft_family_ops *ops; struct nft_chain_list *list; struct nft_chain_list_iter *iter; struct nft_chain *c; bool found = false; /* If built-in chains don't exist for this table, create them */ if (nft_xtables_config_load(h, XTABLES_CONFIG_DEFAULT, 0) < 0) nft_chain_builtin_init(h, table, NULL, NF_ACCEPT); ops = nft_family_ops_lookup(h->family); if (chain && rulenum) { __nft_rule_list(h, chain, table, rulenum, format, ops->print_firewall); return 1; } list = nft_chain_dump(h); iter = nft_chain_list_iter_create(list); if (iter == NULL) goto err; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *chain_table = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_TABLE); const char *chain_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_NAME); uint32_t policy = nft_chain_attr_get_u32(c, NFT_CHAIN_ATTR_POLICY); uint32_t refs = nft_chain_attr_get_u32(c, NFT_CHAIN_ATTR_USE); struct xt_counters ctrs = { .pcnt = nft_chain_attr_get_u64(c, NFT_CHAIN_ATTR_PACKETS), .bcnt = nft_chain_attr_get_u64(c, NFT_CHAIN_ATTR_BYTES), }; bool basechain = false; if (nft_chain_attr_get(c, NFT_CHAIN_ATTR_HOOKNUM)) basechain = true; if (strcmp(table, chain_table) != 0) goto next; if (chain && strcmp(chain, chain_name) != 0) goto next; if (found) printf("\n"); print_header(format, chain_name, policy_name[policy], &ctrs, basechain, refs); __nft_rule_list(h, chain_name, table, rulenum, format, ops->print_firewall); /* we printed the chain we wanted, stop processing. */ if (chain) break; found = true; next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); err: nft_chain_list_free(list); return 1; } static void list_save(struct nft_rule *r, unsigned int num, unsigned int format) { struct iptables_command_state cs = {}; nft_rule_to_iptables_command_state(r, &cs); nft_rule_print_save(&cs, r, NFT_RULE_APPEND, !(format & FMT_NOCOUNTS)); } static int nft_rule_list_chain_save(struct nft_handle *h, const char *chain, const char *table, struct nft_chain_list *list, int counters) { struct nft_chain_list_iter *iter; struct nft_chain *c; iter = nft_chain_list_iter_create(list); if (iter == NULL) return 0; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *chain_table = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_TABLE); const char *chain_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_NAME); uint32_t policy = nft_chain_attr_get_u32(c, NFT_CHAIN_ATTR_POLICY); if (strcmp(table, chain_table) != 0 || (chain && strcmp(chain, chain_name) != 0)) goto next; /* this is a base chain */ if (nft_chain_builtin(c)) { printf("-P %s %s", chain_name, policy_name[policy]); if (counters) { printf(" -c %"PRIu64" %"PRIu64"\n", nft_chain_attr_get_u64(c, NFT_CHAIN_ATTR_PACKETS), nft_chain_attr_get_u64(c, NFT_CHAIN_ATTR_BYTES)); } else printf("\n"); } else { printf("-N %s\n", chain_name); } next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); return 1; } int nft_rule_list_save(struct nft_handle *h, const char *chain, const char *table, int rulenum, int counters) { struct nft_chain_list *list; struct nft_chain_list_iter *iter; struct nft_chain *c; int ret = 1; list = nft_chain_dump(h); /* Dump policies and custom chains first */ if (!rulenum) nft_rule_list_chain_save(h, chain, table, list, counters); /* Now dump out rules in this table */ iter = nft_chain_list_iter_create(list); if (iter == NULL) goto err; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *chain_table = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_TABLE); const char *chain_name = nft_chain_attr_get_str(c, NFT_CHAIN_ATTR_NAME); if (strcmp(table, chain_table) != 0) goto next; if (chain && strcmp(chain, chain_name) != 0) goto next; ret = __nft_rule_list(h, chain_name, table, rulenum, counters ? 0 : FMT_NOCOUNTS, list_save); /* we printed the chain we wanted, stop processing. */ if (chain) break; next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); err: nft_chain_list_free(list); return ret; } int nft_rule_zero_counters(struct nft_handle *h, const char *chain, const char *table, int rulenum) { struct iptables_command_state cs = {}; struct nft_rule_list *list; struct nft_rule *r; int ret = 0; nft_fn = nft_rule_delete; list = nft_rule_list_create(h); if (list == NULL) return 0; r = nft_rule_find(list, chain, table, NULL, rulenum); if (r == NULL) { errno = ENOENT; ret = 1; goto error; } nft_rule_to_iptables_command_state(r, &cs); cs.counters.pcnt = cs.counters.bcnt = 0; ret = nft_rule_append(h, chain, table, &cs, nft_rule_attr_get_u64(r, NFT_RULE_ATTR_HANDLE), false); error: nft_rule_list_destroy(list); return ret; } static int nft_action(struct nft_handle *h, int type) { char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; uint32_t seq; int ret; nlh = mnl_nlmsg_put_header(buf); nlh->nlmsg_type = (NFNL_SUBSYS_NFTABLES<< 8) | type; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; nlh->nlmsg_seq = seq = time(NULL); struct nfgenmsg *nfg = mnl_nlmsg_put_extra_header(nlh, sizeof(*nfg)); nfg->nfgen_family = h->family; nfg->version = NFNETLINK_V0; nfg->res_id = 0; ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) { if (errno != EEXIST) perror("mnl-talk:nft_commit"); } return ret == 0 ? 1 : 0; } int nft_commit(struct nft_handle *h) { return nft_action(h, NFT_MSG_COMMIT); } int nft_abort(struct nft_handle *h) { return nft_action(h, NFT_MSG_ABORT); } int nft_compatible_revision(const char *name, uint8_t rev, int opt) { struct mnl_socket *nl; char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; uint32_t portid, seq, type; int ret = 0; if (opt == IPT_SO_GET_REVISION_MATCH || opt == IP6T_SO_GET_REVISION_MATCH) type = 0; else type = 1; nlh = mnl_nlmsg_put_header(buf); nlh->nlmsg_type = (NFNL_SUBSYS_NFT_COMPAT << 8) | NFNL_MSG_COMPAT_GET; nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; nlh->nlmsg_seq = seq = time(NULL); struct nfgenmsg *nfg = mnl_nlmsg_put_extra_header(nlh, sizeof(*nfg)); nfg->nfgen_family = AF_INET; nfg->version = NFNETLINK_V0; nfg->res_id = 0; mnl_attr_put_strz(nlh, NFTA_COMPAT_NAME, name); mnl_attr_put_u32(nlh, NFTA_COMPAT_REV, htonl(rev)); mnl_attr_put_u32(nlh, NFTA_COMPAT_TYPE, htonl(type)); DEBUGP("requesting `%s' rev=%d type=%d via nft_compat\n", name, rev, type); nl = mnl_socket_open(NETLINK_NETFILTER); if (nl == NULL) { perror("mnl_socket_open"); return 0; } if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) { perror("mnl_socket_bind"); goto err; } portid = mnl_socket_get_portid(nl); if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) { perror("mnl_socket_send"); goto err; } ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); if (ret == -1) { perror("mnl_socket_recvfrom"); goto err; } ret = mnl_cb_run(buf, ret, seq, portid, NULL, NULL); if (ret == -1) { perror("mnl_cb_run"); goto err; } err: mnl_socket_close(nl); return ret < 0 ? 0 : 1; } /* Translates errno numbers into more human-readable form than strerror. */ const char *nft_strerror(int err) { unsigned int i; static struct table_struct { void *fn; int err; const char *message; } table[] = { { nft_chain_user_del, ENOTEMPTY, "Chain is not empty" }, { nft_chain_user_del, EINVAL, "Can't delete built-in chain" }, { nft_chain_user_del, EMLINK, "Can't delete chain with references left" }, { nft_chain_user_add, EEXIST, "Chain already exists" }, { nft_rule_add, E2BIG, "Index of insertion too big" }, { nft_rule_replace, E2BIG, "Index of replacement too big" }, { nft_rule_delete_num, E2BIG, "Index of deletion too big" }, /* { TC_READ_COUNTER, E2BIG, "Index of counter too big" }, { TC_ZERO_COUNTER, E2BIG, "Index of counter too big" }, */ { nft_rule_add, ELOOP, "Loop found in table" }, { nft_rule_add, EINVAL, "Target problem" }, /* ENOENT for DELETE probably means no matching rule */ { nft_rule_delete, ENOENT, "Bad rule (does a matching rule exist in that chain?)" }, { nft_chain_set, ENOENT, "Bad built-in chain name" }, { nft_chain_set, EINVAL, "Bad policy name" }, { NULL, EPERM, "Permission denied (you must be root)" }, { NULL, 0, "Incompatible with this kernel" }, { NULL, ENOPROTOOPT, "iptables who? (do you need to insmod?)" }, { NULL, ENOSYS, "Will be implemented real soon. I promise ;)" }, { NULL, ENOMEM, "Memory allocation problem" }, { NULL, ENOENT, "No chain/target/match by that name" }, }; for (i = 0; i < sizeof(table)/sizeof(struct table_struct); i++) { if ((!table[i].fn || table[i].fn == nft_fn) && table[i].err == err) return table[i].message; } return strerror(err); } static void xtables_config_perror(uint32_t flags, const char *fmt, ...) { va_list args; va_start(args, fmt); if (flags & NFT_LOAD_VERBOSE) vfprintf(stderr, fmt, args); va_end(args); } int nft_xtables_config_load(struct nft_handle *h, const char *filename, uint32_t flags) { struct nft_table_list *table_list = nft_table_list_alloc(); struct nft_chain_list *chain_list = nft_chain_list_alloc(); struct nft_table_list_iter *titer; struct nft_chain_list_iter *citer; struct nft_table *table; struct nft_chain *chain; uint32_t table_family, chain_family; bool found = false; if (xtables_config_parse(filename, table_list, chain_list) < 0) { if (errno == ENOENT) { xtables_config_perror(flags, "configuration file `%s' does not exists\n", filename); } else { xtables_config_perror(flags, "Fatal error parsing config file: %s\n", strerror(errno)); } return -1; } /* Stage 1) create tables */ titer = nft_table_list_iter_create(table_list); while ((table = nft_table_list_iter_next(titer)) != NULL) { table_family = nft_table_attr_get_u32(table, NFT_TABLE_ATTR_FAMILY); if (h->family != table_family) continue; found = true; if (nft_table_add(h, table) < 0) { if (errno == EEXIST) { xtables_config_perror(flags, "table `%s' already exists, skipping\n", (char *)nft_table_attr_get(table, NFT_TABLE_ATTR_NAME)); } else { xtables_config_perror(flags, "table `%s' cannot be create, reason `%s'. Exitting\n", (char *)nft_table_attr_get(table, NFT_TABLE_ATTR_NAME), strerror(errno)); nft_table_list_iter_destroy(titer); nft_table_list_free(table_list); return -1; } continue; } xtables_config_perror(flags, "table `%s' has been created\n", (char *)nft_table_attr_get(table, NFT_TABLE_ATTR_NAME)); } nft_table_list_iter_destroy(titer); nft_table_list_free(table_list); if (!found) return -1; /* Stage 2) create chains */ citer = nft_chain_list_iter_create(chain_list); while ((chain = nft_chain_list_iter_next(citer)) != NULL) { chain_family = nft_chain_attr_get_u32(chain, NFT_CHAIN_ATTR_TABLE); if (h->family != chain_family) continue; if (nft_chain_add(h, chain) < 0) { if (errno == EEXIST) { xtables_config_perror(flags, "chain `%s' already exists in table `%s', skipping\n", (char *)nft_chain_attr_get(chain, NFT_CHAIN_ATTR_NAME), (char *)nft_chain_attr_get(chain, NFT_CHAIN_ATTR_TABLE)); } else { xtables_config_perror(flags, "chain `%s' cannot be create, reason `%s'. Exitting\n", (char *)nft_chain_attr_get(chain, NFT_CHAIN_ATTR_NAME), strerror(errno)); nft_chain_list_iter_destroy(citer); nft_chain_list_free(chain_list); return -1; } continue; } xtables_config_perror(flags, "chain `%s' in table `%s' has been created\n", (char *)nft_chain_attr_get(chain, NFT_CHAIN_ATTR_NAME), (char *)nft_chain_attr_get(chain, NFT_CHAIN_ATTR_TABLE)); } nft_chain_list_iter_destroy(citer); nft_chain_list_free(chain_list); return 0; } int nft_chain_zero_counters(struct nft_handle *h, const char *chain, const char *table) { struct nft_chain_list *list; struct nft_chain_list_iter *iter; struct nft_chain *c; struct nlmsghdr *nlh; char buf[MNL_SOCKET_BUFFER_SIZE]; int ret = 0; list = nft_chain_list_get(h); if (list == NULL) goto err; iter = nft_chain_list_iter_create(list); if (iter == NULL) goto err; c = nft_chain_list_iter_next(iter); while (c != NULL) { const char *chain_name = nft_chain_attr_get(c, NFT_CHAIN_ATTR_NAME); const char *chain_table = nft_chain_attr_get(c, NFT_CHAIN_ATTR_TABLE); if (strcmp(table, chain_table) != 0) goto next; if (chain != NULL && strcmp(chain, chain_name) != 0) goto next; nft_chain_attr_set_u64(c, NFT_CHAIN_ATTR_PACKETS, 0); nft_chain_attr_set_u64(c, NFT_CHAIN_ATTR_BYTES, 0); nft_chain_attr_unset(c, NFT_CHAIN_ATTR_HANDLE); nlh = nft_chain_nlmsg_build_hdr(buf, NFT_MSG_NEWCHAIN, h->family, NLM_F_ACK, h->seq); nft_chain_nlmsg_build_payload(nlh, c); ret = mnl_talk(h, nlh, NULL, NULL); if (ret < 0) perror("mnl_talk:nft_chain_zero_counters"); if (chain != NULL) break; next: c = nft_chain_list_iter_next(iter); } nft_chain_list_iter_destroy(iter); err: nft_chain_list_free(list); /* the core expects 1 for success and 0 for error */ return ret == 0 ? 1 : 0; }