| /* |
| * (C) 2012-2013 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 version 2 as |
| * published by the Free Software Foundation. |
| * |
| * This software has been sponsored by Sophos Astaro <http://www.sophos.com> |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/netlink.h> |
| #include <linux/netfilter.h> |
| #include <linux/netfilter/nfnetlink.h> |
| #include <linux/netfilter/nf_tables.h> |
| #include <linux/netfilter/nf_tables_compat.h> |
| #include <linux/netfilter/x_tables.h> |
| #include <linux/netfilter_ipv4/ip_tables.h> |
| #include <linux/netfilter_ipv6/ip6_tables.h> |
| #include <linux/netfilter_bridge/ebtables.h> |
| #include <net/netfilter/nf_tables.h> |
| |
| static int nft_compat_chain_validate_dependency(const char *tablename, |
| const struct nft_chain *chain) |
| { |
| const struct nft_base_chain *basechain; |
| |
| if (!tablename || !(chain->flags & NFT_BASE_CHAIN)) |
| return 0; |
| |
| basechain = nft_base_chain(chain); |
| if (strcmp(tablename, "nat") == 0 && |
| basechain->type->type != NFT_CHAIN_T_NAT) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| union nft_entry { |
| struct ipt_entry e4; |
| struct ip6t_entry e6; |
| struct ebt_entry ebt; |
| }; |
| |
| static inline void |
| nft_compat_set_par(struct xt_action_param *par, void *xt, const void *xt_info) |
| { |
| par->target = xt; |
| par->targinfo = xt_info; |
| par->hotdrop = false; |
| } |
| |
| static void nft_target_eval_xt(const struct nft_expr *expr, |
| struct nft_data data[NFT_REG_MAX + 1], |
| const struct nft_pktinfo *pkt) |
| { |
| void *info = nft_expr_priv(expr); |
| struct xt_target *target = expr->ops->data; |
| struct sk_buff *skb = pkt->skb; |
| int ret; |
| |
| nft_compat_set_par((struct xt_action_param *)&pkt->xt, target, info); |
| |
| ret = target->target(skb, &pkt->xt); |
| |
| if (pkt->xt.hotdrop) |
| ret = NF_DROP; |
| |
| switch (ret) { |
| case XT_CONTINUE: |
| data[NFT_REG_VERDICT].verdict = NFT_CONTINUE; |
| break; |
| default: |
| data[NFT_REG_VERDICT].verdict = ret; |
| break; |
| } |
| } |
| |
| static void nft_target_eval_bridge(const struct nft_expr *expr, |
| struct nft_data data[NFT_REG_MAX + 1], |
| const struct nft_pktinfo *pkt) |
| { |
| void *info = nft_expr_priv(expr); |
| struct xt_target *target = expr->ops->data; |
| struct sk_buff *skb = pkt->skb; |
| int ret; |
| |
| nft_compat_set_par((struct xt_action_param *)&pkt->xt, target, info); |
| |
| ret = target->target(skb, &pkt->xt); |
| |
| if (pkt->xt.hotdrop) |
| ret = NF_DROP; |
| |
| switch (ret) { |
| case EBT_ACCEPT: |
| data[NFT_REG_VERDICT].verdict = NF_ACCEPT; |
| break; |
| case EBT_DROP: |
| data[NFT_REG_VERDICT].verdict = NF_DROP; |
| break; |
| case EBT_CONTINUE: |
| data[NFT_REG_VERDICT].verdict = NFT_CONTINUE; |
| break; |
| case EBT_RETURN: |
| data[NFT_REG_VERDICT].verdict = NFT_RETURN; |
| break; |
| default: |
| data[NFT_REG_VERDICT].verdict = ret; |
| break; |
| } |
| } |
| |
| static const struct nla_policy nft_target_policy[NFTA_TARGET_MAX + 1] = { |
| [NFTA_TARGET_NAME] = { .type = NLA_NUL_STRING }, |
| [NFTA_TARGET_REV] = { .type = NLA_U32 }, |
| [NFTA_TARGET_INFO] = { .type = NLA_BINARY }, |
| }; |
| |
| static void |
| nft_target_set_tgchk_param(struct xt_tgchk_param *par, |
| const struct nft_ctx *ctx, |
| struct xt_target *target, void *info, |
| union nft_entry *entry, u16 proto, bool inv) |
| { |
| par->net = ctx->net; |
| par->table = ctx->table->name; |
| switch (ctx->afi->family) { |
| case AF_INET: |
| entry->e4.ip.proto = proto; |
| entry->e4.ip.invflags = inv ? IPT_INV_PROTO : 0; |
| break; |
| case AF_INET6: |
| if (proto) |
| entry->e6.ipv6.flags |= IP6T_F_PROTO; |
| |
| entry->e6.ipv6.proto = proto; |
| entry->e6.ipv6.invflags = inv ? IP6T_INV_PROTO : 0; |
| break; |
| case NFPROTO_BRIDGE: |
| entry->ebt.ethproto = (__force __be16)proto; |
| entry->ebt.invflags = inv ? EBT_IPROTO : 0; |
| break; |
| } |
| par->entryinfo = entry; |
| par->target = target; |
| par->targinfo = info; |
| if (ctx->chain->flags & NFT_BASE_CHAIN) { |
| const struct nft_base_chain *basechain = |
| nft_base_chain(ctx->chain); |
| const struct nf_hook_ops *ops = &basechain->ops[0]; |
| |
| par->hook_mask = 1 << ops->hooknum; |
| } else { |
| par->hook_mask = 0; |
| } |
| par->family = ctx->afi->family; |
| } |
| |
| static void target_compat_from_user(struct xt_target *t, void *in, void *out) |
| { |
| int pad; |
| |
| memcpy(out, in, t->targetsize); |
| pad = XT_ALIGN(t->targetsize) - t->targetsize; |
| if (pad > 0) |
| memset(out + t->targetsize, 0, pad); |
| } |
| |
| static const struct nla_policy nft_rule_compat_policy[NFTA_RULE_COMPAT_MAX + 1] = { |
| [NFTA_RULE_COMPAT_PROTO] = { .type = NLA_U32 }, |
| [NFTA_RULE_COMPAT_FLAGS] = { .type = NLA_U32 }, |
| }; |
| |
| static int nft_parse_compat(const struct nlattr *attr, u16 *proto, bool *inv) |
| { |
| struct nlattr *tb[NFTA_RULE_COMPAT_MAX+1]; |
| u32 flags; |
| int err; |
| |
| err = nla_parse_nested(tb, NFTA_RULE_COMPAT_MAX, attr, |
| nft_rule_compat_policy); |
| if (err < 0) |
| return err; |
| |
| if (!tb[NFTA_RULE_COMPAT_PROTO] || !tb[NFTA_RULE_COMPAT_FLAGS]) |
| return -EINVAL; |
| |
| flags = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_FLAGS])); |
| if (flags & ~NFT_RULE_COMPAT_F_MASK) |
| return -EINVAL; |
| if (flags & NFT_RULE_COMPAT_F_INV) |
| *inv = true; |
| |
| *proto = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_PROTO])); |
| return 0; |
| } |
| |
| static int |
| nft_target_init(const struct nft_ctx *ctx, const struct nft_expr *expr, |
| const struct nlattr * const tb[]) |
| { |
| void *info = nft_expr_priv(expr); |
| struct xt_target *target = expr->ops->data; |
| struct xt_tgchk_param par; |
| size_t size = XT_ALIGN(nla_len(tb[NFTA_TARGET_INFO])); |
| u16 proto = 0; |
| bool inv = false; |
| union nft_entry e = {}; |
| int ret; |
| |
| ret = nft_compat_chain_validate_dependency(target->table, ctx->chain); |
| if (ret < 0) |
| goto err; |
| |
| target_compat_from_user(target, nla_data(tb[NFTA_TARGET_INFO]), info); |
| |
| if (ctx->nla[NFTA_RULE_COMPAT]) { |
| ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv); |
| if (ret < 0) |
| goto err; |
| } |
| |
| nft_target_set_tgchk_param(&par, ctx, target, info, &e, proto, inv); |
| |
| ret = xt_check_target(&par, size, proto, inv); |
| if (ret < 0) |
| goto err; |
| |
| /* The standard target cannot be used */ |
| if (target->target == NULL) { |
| ret = -EINVAL; |
| goto err; |
| } |
| |
| return 0; |
| err: |
| module_put(target->me); |
| return ret; |
| } |
| |
| static void |
| nft_target_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) |
| { |
| struct xt_target *target = expr->ops->data; |
| void *info = nft_expr_priv(expr); |
| struct xt_tgdtor_param par; |
| |
| par.net = ctx->net; |
| par.target = target; |
| par.targinfo = info; |
| par.family = ctx->afi->family; |
| if (par.target->destroy != NULL) |
| par.target->destroy(&par); |
| |
| module_put(target->me); |
| } |
| |
| static int nft_target_dump(struct sk_buff *skb, const struct nft_expr *expr) |
| { |
| const struct xt_target *target = expr->ops->data; |
| void *info = nft_expr_priv(expr); |
| |
| if (nla_put_string(skb, NFTA_TARGET_NAME, target->name) || |
| nla_put_be32(skb, NFTA_TARGET_REV, htonl(target->revision)) || |
| nla_put(skb, NFTA_TARGET_INFO, XT_ALIGN(target->targetsize), info)) |
| goto nla_put_failure; |
| |
| return 0; |
| |
| nla_put_failure: |
| return -1; |
| } |
| |
| static int nft_target_validate(const struct nft_ctx *ctx, |
| const struct nft_expr *expr, |
| const struct nft_data **data) |
| { |
| struct xt_target *target = expr->ops->data; |
| unsigned int hook_mask = 0; |
| int ret; |
| |
| if (ctx->chain->flags & NFT_BASE_CHAIN) { |
| const struct nft_base_chain *basechain = |
| nft_base_chain(ctx->chain); |
| const struct nf_hook_ops *ops = &basechain->ops[0]; |
| |
| hook_mask = 1 << ops->hooknum; |
| if (!(hook_mask & target->hooks)) |
| return -EINVAL; |
| |
| ret = nft_compat_chain_validate_dependency(target->table, |
| ctx->chain); |
| if (ret < 0) |
| return ret; |
| } |
| return 0; |
| } |
| |
| static void nft_match_eval(const struct nft_expr *expr, |
| struct nft_data data[NFT_REG_MAX + 1], |
| const struct nft_pktinfo *pkt) |
| { |
| void *info = nft_expr_priv(expr); |
| struct xt_match *match = expr->ops->data; |
| struct sk_buff *skb = pkt->skb; |
| bool ret; |
| |
| nft_compat_set_par((struct xt_action_param *)&pkt->xt, match, info); |
| |
| ret = match->match(skb, (struct xt_action_param *)&pkt->xt); |
| |
| if (pkt->xt.hotdrop) { |
| data[NFT_REG_VERDICT].verdict = NF_DROP; |
| return; |
| } |
| |
| switch(ret) { |
| case true: |
| data[NFT_REG_VERDICT].verdict = NFT_CONTINUE; |
| break; |
| case false: |
| data[NFT_REG_VERDICT].verdict = NFT_BREAK; |
| break; |
| } |
| } |
| |
| static const struct nla_policy nft_match_policy[NFTA_MATCH_MAX + 1] = { |
| [NFTA_MATCH_NAME] = { .type = NLA_NUL_STRING }, |
| [NFTA_MATCH_REV] = { .type = NLA_U32 }, |
| [NFTA_MATCH_INFO] = { .type = NLA_BINARY }, |
| }; |
| |
| /* struct xt_mtchk_param and xt_tgchk_param look very similar */ |
| static void |
| nft_match_set_mtchk_param(struct xt_mtchk_param *par, const struct nft_ctx *ctx, |
| struct xt_match *match, void *info, |
| union nft_entry *entry, u16 proto, bool inv) |
| { |
| par->net = ctx->net; |
| par->table = ctx->table->name; |
| switch (ctx->afi->family) { |
| case AF_INET: |
| entry->e4.ip.proto = proto; |
| entry->e4.ip.invflags = inv ? IPT_INV_PROTO : 0; |
| break; |
| case AF_INET6: |
| if (proto) |
| entry->e6.ipv6.flags |= IP6T_F_PROTO; |
| |
| entry->e6.ipv6.proto = proto; |
| entry->e6.ipv6.invflags = inv ? IP6T_INV_PROTO : 0; |
| break; |
| case NFPROTO_BRIDGE: |
| entry->ebt.ethproto = (__force __be16)proto; |
| entry->ebt.invflags = inv ? EBT_IPROTO : 0; |
| break; |
| } |
| par->entryinfo = entry; |
| par->match = match; |
| par->matchinfo = info; |
| if (ctx->chain->flags & NFT_BASE_CHAIN) { |
| const struct nft_base_chain *basechain = |
| nft_base_chain(ctx->chain); |
| const struct nf_hook_ops *ops = &basechain->ops[0]; |
| |
| par->hook_mask = 1 << ops->hooknum; |
| } else { |
| par->hook_mask = 0; |
| } |
| par->family = ctx->afi->family; |
| } |
| |
| static void match_compat_from_user(struct xt_match *m, void *in, void *out) |
| { |
| int pad; |
| |
| memcpy(out, in, m->matchsize); |
| pad = XT_ALIGN(m->matchsize) - m->matchsize; |
| if (pad > 0) |
| memset(out + m->matchsize, 0, pad); |
| } |
| |
| static int |
| nft_match_init(const struct nft_ctx *ctx, const struct nft_expr *expr, |
| const struct nlattr * const tb[]) |
| { |
| void *info = nft_expr_priv(expr); |
| struct xt_match *match = expr->ops->data; |
| struct xt_mtchk_param par; |
| size_t size = XT_ALIGN(nla_len(tb[NFTA_MATCH_INFO])); |
| u16 proto = 0; |
| bool inv = false; |
| union nft_entry e = {}; |
| int ret; |
| |
| ret = nft_compat_chain_validate_dependency(match->table, ctx->chain); |
| if (ret < 0) |
| goto err; |
| |
| match_compat_from_user(match, nla_data(tb[NFTA_MATCH_INFO]), info); |
| |
| if (ctx->nla[NFTA_RULE_COMPAT]) { |
| ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv); |
| if (ret < 0) |
| goto err; |
| } |
| |
| nft_match_set_mtchk_param(&par, ctx, match, info, &e, proto, inv); |
| |
| ret = xt_check_match(&par, size, proto, inv); |
| if (ret < 0) |
| goto err; |
| |
| return 0; |
| err: |
| module_put(match->me); |
| return ret; |
| } |
| |
| static void |
| nft_match_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) |
| { |
| struct xt_match *match = expr->ops->data; |
| void *info = nft_expr_priv(expr); |
| struct xt_mtdtor_param par; |
| |
| par.net = ctx->net; |
| par.match = match; |
| par.matchinfo = info; |
| par.family = ctx->afi->family; |
| if (par.match->destroy != NULL) |
| par.match->destroy(&par); |
| |
| module_put(match->me); |
| } |
| |
| static int nft_match_dump(struct sk_buff *skb, const struct nft_expr *expr) |
| { |
| void *info = nft_expr_priv(expr); |
| struct xt_match *match = expr->ops->data; |
| |
| if (nla_put_string(skb, NFTA_MATCH_NAME, match->name) || |
| nla_put_be32(skb, NFTA_MATCH_REV, htonl(match->revision)) || |
| nla_put(skb, NFTA_MATCH_INFO, XT_ALIGN(match->matchsize), info)) |
| goto nla_put_failure; |
| |
| return 0; |
| |
| nla_put_failure: |
| return -1; |
| } |
| |
| static int nft_match_validate(const struct nft_ctx *ctx, |
| const struct nft_expr *expr, |
| const struct nft_data **data) |
| { |
| struct xt_match *match = expr->ops->data; |
| unsigned int hook_mask = 0; |
| int ret; |
| |
| if (ctx->chain->flags & NFT_BASE_CHAIN) { |
| const struct nft_base_chain *basechain = |
| nft_base_chain(ctx->chain); |
| const struct nf_hook_ops *ops = &basechain->ops[0]; |
| |
| hook_mask = 1 << ops->hooknum; |
| if (!(hook_mask & match->hooks)) |
| return -EINVAL; |
| |
| ret = nft_compat_chain_validate_dependency(match->table, |
| ctx->chain); |
| if (ret < 0) |
| return ret; |
| } |
| return 0; |
| } |
| |
| static int |
| nfnl_compat_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type, |
| int event, u16 family, const char *name, |
| int rev, int target) |
| { |
| struct nlmsghdr *nlh; |
| struct nfgenmsg *nfmsg; |
| unsigned int flags = portid ? NLM_F_MULTI : 0; |
| |
| event |= NFNL_SUBSYS_NFT_COMPAT << 8; |
| nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags); |
| if (nlh == NULL) |
| goto nlmsg_failure; |
| |
| nfmsg = nlmsg_data(nlh); |
| nfmsg->nfgen_family = family; |
| nfmsg->version = NFNETLINK_V0; |
| nfmsg->res_id = 0; |
| |
| if (nla_put_string(skb, NFTA_COMPAT_NAME, name) || |
| nla_put_be32(skb, NFTA_COMPAT_REV, htonl(rev)) || |
| nla_put_be32(skb, NFTA_COMPAT_TYPE, htonl(target))) |
| goto nla_put_failure; |
| |
| nlmsg_end(skb, nlh); |
| return skb->len; |
| |
| nlmsg_failure: |
| nla_put_failure: |
| nlmsg_cancel(skb, nlh); |
| return -1; |
| } |
| |
| static int |
| nfnl_compat_get(struct sock *nfnl, struct sk_buff *skb, |
| const struct nlmsghdr *nlh, const struct nlattr * const tb[]) |
| { |
| int ret = 0, target; |
| struct nfgenmsg *nfmsg; |
| const char *fmt; |
| const char *name; |
| u32 rev; |
| struct sk_buff *skb2; |
| |
| if (tb[NFTA_COMPAT_NAME] == NULL || |
| tb[NFTA_COMPAT_REV] == NULL || |
| tb[NFTA_COMPAT_TYPE] == NULL) |
| return -EINVAL; |
| |
| name = nla_data(tb[NFTA_COMPAT_NAME]); |
| rev = ntohl(nla_get_be32(tb[NFTA_COMPAT_REV])); |
| target = ntohl(nla_get_be32(tb[NFTA_COMPAT_TYPE])); |
| |
| nfmsg = nlmsg_data(nlh); |
| |
| switch(nfmsg->nfgen_family) { |
| case AF_INET: |
| fmt = "ipt_%s"; |
| break; |
| case AF_INET6: |
| fmt = "ip6t_%s"; |
| break; |
| case NFPROTO_BRIDGE: |
| fmt = "ebt_%s"; |
| break; |
| default: |
| pr_err("nft_compat: unsupported protocol %d\n", |
| nfmsg->nfgen_family); |
| return -EINVAL; |
| } |
| |
| try_then_request_module(xt_find_revision(nfmsg->nfgen_family, name, |
| rev, target, &ret), |
| fmt, name); |
| |
| if (ret < 0) |
| return ret; |
| |
| skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
| if (skb2 == NULL) |
| return -ENOMEM; |
| |
| /* include the best revision for this extension in the message */ |
| if (nfnl_compat_fill_info(skb2, NETLINK_CB(skb).portid, |
| nlh->nlmsg_seq, |
| NFNL_MSG_TYPE(nlh->nlmsg_type), |
| NFNL_MSG_COMPAT_GET, |
| nfmsg->nfgen_family, |
| name, ret, target) <= 0) { |
| kfree_skb(skb2); |
| return -ENOSPC; |
| } |
| |
| ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid, |
| MSG_DONTWAIT); |
| if (ret > 0) |
| ret = 0; |
| |
| return ret == -EAGAIN ? -ENOBUFS : ret; |
| } |
| |
| static const struct nla_policy nfnl_compat_policy_get[NFTA_COMPAT_MAX+1] = { |
| [NFTA_COMPAT_NAME] = { .type = NLA_NUL_STRING, |
| .len = NFT_COMPAT_NAME_MAX-1 }, |
| [NFTA_COMPAT_REV] = { .type = NLA_U32 }, |
| [NFTA_COMPAT_TYPE] = { .type = NLA_U32 }, |
| }; |
| |
| static const struct nfnl_callback nfnl_nft_compat_cb[NFNL_MSG_COMPAT_MAX] = { |
| [NFNL_MSG_COMPAT_GET] = { .call = nfnl_compat_get, |
| .attr_count = NFTA_COMPAT_MAX, |
| .policy = nfnl_compat_policy_get }, |
| }; |
| |
| static const struct nfnetlink_subsystem nfnl_compat_subsys = { |
| .name = "nft-compat", |
| .subsys_id = NFNL_SUBSYS_NFT_COMPAT, |
| .cb_count = NFNL_MSG_COMPAT_MAX, |
| .cb = nfnl_nft_compat_cb, |
| }; |
| |
| static LIST_HEAD(nft_match_list); |
| |
| struct nft_xt { |
| struct list_head head; |
| struct nft_expr_ops ops; |
| }; |
| |
| static struct nft_expr_type nft_match_type; |
| |
| static const struct nft_expr_ops * |
| nft_match_select_ops(const struct nft_ctx *ctx, |
| const struct nlattr * const tb[]) |
| { |
| struct nft_xt *nft_match; |
| struct xt_match *match; |
| char *mt_name; |
| __u32 rev, family; |
| |
| if (tb[NFTA_MATCH_NAME] == NULL || |
| tb[NFTA_MATCH_REV] == NULL || |
| tb[NFTA_MATCH_INFO] == NULL) |
| return ERR_PTR(-EINVAL); |
| |
| mt_name = nla_data(tb[NFTA_MATCH_NAME]); |
| rev = ntohl(nla_get_be32(tb[NFTA_MATCH_REV])); |
| family = ctx->afi->family; |
| |
| /* Re-use the existing match if it's already loaded. */ |
| list_for_each_entry(nft_match, &nft_match_list, head) { |
| struct xt_match *match = nft_match->ops.data; |
| |
| if (strcmp(match->name, mt_name) == 0 && |
| match->revision == rev && match->family == family) { |
| if (!try_module_get(match->me)) |
| return ERR_PTR(-ENOENT); |
| |
| return &nft_match->ops; |
| } |
| } |
| |
| match = xt_request_find_match(family, mt_name, rev); |
| if (IS_ERR(match)) |
| return ERR_PTR(-ENOENT); |
| |
| /* This is the first time we use this match, allocate operations */ |
| nft_match = kzalloc(sizeof(struct nft_xt), GFP_KERNEL); |
| if (nft_match == NULL) |
| return ERR_PTR(-ENOMEM); |
| |
| nft_match->ops.type = &nft_match_type; |
| nft_match->ops.size = NFT_EXPR_SIZE(XT_ALIGN(match->matchsize)); |
| nft_match->ops.eval = nft_match_eval; |
| nft_match->ops.init = nft_match_init; |
| nft_match->ops.destroy = nft_match_destroy; |
| nft_match->ops.dump = nft_match_dump; |
| nft_match->ops.validate = nft_match_validate; |
| nft_match->ops.data = match; |
| |
| list_add(&nft_match->head, &nft_match_list); |
| |
| return &nft_match->ops; |
| } |
| |
| static void nft_match_release(void) |
| { |
| struct nft_xt *nft_match, *tmp; |
| |
| list_for_each_entry_safe(nft_match, tmp, &nft_match_list, head) |
| kfree(nft_match); |
| } |
| |
| static struct nft_expr_type nft_match_type __read_mostly = { |
| .name = "match", |
| .select_ops = nft_match_select_ops, |
| .policy = nft_match_policy, |
| .maxattr = NFTA_MATCH_MAX, |
| .owner = THIS_MODULE, |
| }; |
| |
| static LIST_HEAD(nft_target_list); |
| |
| static struct nft_expr_type nft_target_type; |
| |
| static const struct nft_expr_ops * |
| nft_target_select_ops(const struct nft_ctx *ctx, |
| const struct nlattr * const tb[]) |
| { |
| struct nft_xt *nft_target; |
| struct xt_target *target; |
| char *tg_name; |
| __u32 rev, family; |
| |
| if (tb[NFTA_TARGET_NAME] == NULL || |
| tb[NFTA_TARGET_REV] == NULL || |
| tb[NFTA_TARGET_INFO] == NULL) |
| return ERR_PTR(-EINVAL); |
| |
| tg_name = nla_data(tb[NFTA_TARGET_NAME]); |
| rev = ntohl(nla_get_be32(tb[NFTA_TARGET_REV])); |
| family = ctx->afi->family; |
| |
| /* Re-use the existing target if it's already loaded. */ |
| list_for_each_entry(nft_target, &nft_target_list, head) { |
| struct xt_target *target = nft_target->ops.data; |
| |
| if (strcmp(target->name, tg_name) == 0 && |
| target->revision == rev && target->family == family) { |
| if (!try_module_get(target->me)) |
| return ERR_PTR(-ENOENT); |
| |
| return &nft_target->ops; |
| } |
| } |
| |
| target = xt_request_find_target(family, tg_name, rev); |
| if (IS_ERR(target)) |
| return ERR_PTR(-ENOENT); |
| |
| /* This is the first time we use this target, allocate operations */ |
| nft_target = kzalloc(sizeof(struct nft_xt), GFP_KERNEL); |
| if (nft_target == NULL) |
| return ERR_PTR(-ENOMEM); |
| |
| nft_target->ops.type = &nft_target_type; |
| nft_target->ops.size = NFT_EXPR_SIZE(XT_ALIGN(target->targetsize)); |
| nft_target->ops.init = nft_target_init; |
| nft_target->ops.destroy = nft_target_destroy; |
| nft_target->ops.dump = nft_target_dump; |
| nft_target->ops.validate = nft_target_validate; |
| nft_target->ops.data = target; |
| |
| if (family == NFPROTO_BRIDGE) |
| nft_target->ops.eval = nft_target_eval_bridge; |
| else |
| nft_target->ops.eval = nft_target_eval_xt; |
| |
| list_add(&nft_target->head, &nft_target_list); |
| |
| return &nft_target->ops; |
| } |
| |
| static void nft_target_release(void) |
| { |
| struct nft_xt *nft_target, *tmp; |
| |
| list_for_each_entry_safe(nft_target, tmp, &nft_target_list, head) |
| kfree(nft_target); |
| } |
| |
| static struct nft_expr_type nft_target_type __read_mostly = { |
| .name = "target", |
| .select_ops = nft_target_select_ops, |
| .policy = nft_target_policy, |
| .maxattr = NFTA_TARGET_MAX, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init nft_compat_module_init(void) |
| { |
| int ret; |
| |
| ret = nft_register_expr(&nft_match_type); |
| if (ret < 0) |
| return ret; |
| |
| ret = nft_register_expr(&nft_target_type); |
| if (ret < 0) |
| goto err_match; |
| |
| ret = nfnetlink_subsys_register(&nfnl_compat_subsys); |
| if (ret < 0) { |
| pr_err("nft_compat: cannot register with nfnetlink.\n"); |
| goto err_target; |
| } |
| |
| pr_info("nf_tables_compat: (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>\n"); |
| |
| return ret; |
| |
| err_target: |
| nft_unregister_expr(&nft_target_type); |
| err_match: |
| nft_unregister_expr(&nft_match_type); |
| return ret; |
| } |
| |
| static void __exit nft_compat_module_exit(void) |
| { |
| nfnetlink_subsys_unregister(&nfnl_compat_subsys); |
| nft_unregister_expr(&nft_target_type); |
| nft_unregister_expr(&nft_match_type); |
| nft_match_release(); |
| nft_target_release(); |
| } |
| |
| MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_NFT_COMPAT); |
| |
| module_init(nft_compat_module_init); |
| module_exit(nft_compat_module_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>"); |
| MODULE_ALIAS_NFT_EXPR("match"); |
| MODULE_ALIAS_NFT_EXPR("target"); |