diff options
Diffstat (limited to 'net/netfilter/nft_ct.c')
| -rw-r--r-- | net/netfilter/nft_ct.c | 1401 |
1 files changed, 1401 insertions, 0 deletions
diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c new file mode 100644 index 000000000..641dc21f9 --- /dev/null +++ b/net/netfilter/nft_ct.c @@ -0,0 +1,1401 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> + * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org> + * + * Development of this code funded by Astaro AG (http://www.astaro.com/) + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/netlink.h> +#include <linux/netfilter.h> +#include <linux/netfilter/nf_tables.h> +#include <net/netfilter/nf_tables.h> +#include <net/netfilter/nf_conntrack.h> +#include <net/netfilter/nf_conntrack_acct.h> +#include <net/netfilter/nf_conntrack_tuple.h> +#include <net/netfilter/nf_conntrack_helper.h> +#include <net/netfilter/nf_conntrack_ecache.h> +#include <net/netfilter/nf_conntrack_labels.h> +#include <net/netfilter/nf_conntrack_timeout.h> +#include <net/netfilter/nf_conntrack_l4proto.h> +#include <net/netfilter/nf_conntrack_expect.h> + +struct nft_ct { + enum nft_ct_keys key:8; + enum ip_conntrack_dir dir:8; + u8 len; + union { + u8 dreg; + u8 sreg; + }; +}; + +struct nft_ct_helper_obj { + struct nf_conntrack_helper *helper4; + struct nf_conntrack_helper *helper6; + u8 l4proto; +}; + +#ifdef CONFIG_NF_CONNTRACK_ZONES +static DEFINE_PER_CPU(struct nf_conn *, nft_ct_pcpu_template); +static unsigned int nft_ct_pcpu_template_refcnt __read_mostly; +static DEFINE_MUTEX(nft_ct_pcpu_mutex); +#endif + +static u64 nft_ct_get_eval_counter(const struct nf_conn_counter *c, + enum nft_ct_keys k, + enum ip_conntrack_dir d) +{ + if (d < IP_CT_DIR_MAX) + return k == NFT_CT_BYTES ? atomic64_read(&c[d].bytes) : + atomic64_read(&c[d].packets); + + return nft_ct_get_eval_counter(c, k, IP_CT_DIR_ORIGINAL) + + nft_ct_get_eval_counter(c, k, IP_CT_DIR_REPLY); +} + +static void nft_ct_get_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct *priv = nft_expr_priv(expr); + u32 *dest = ®s->data[priv->dreg]; + enum ip_conntrack_info ctinfo; + const struct nf_conn *ct; + const struct nf_conn_help *help; + const struct nf_conntrack_tuple *tuple; + const struct nf_conntrack_helper *helper; + unsigned int state; + + ct = nf_ct_get(pkt->skb, &ctinfo); + + switch (priv->key) { + case NFT_CT_STATE: + if (ct) + state = NF_CT_STATE_BIT(ctinfo); + else if (ctinfo == IP_CT_UNTRACKED) + state = NF_CT_STATE_UNTRACKED_BIT; + else + state = NF_CT_STATE_INVALID_BIT; + *dest = state; + return; + default: + break; + } + + if (ct == NULL) + goto err; + + switch (priv->key) { + case NFT_CT_DIRECTION: + nft_reg_store8(dest, CTINFO2DIR(ctinfo)); + return; + case NFT_CT_STATUS: + *dest = ct->status; + return; +#ifdef CONFIG_NF_CONNTRACK_MARK + case NFT_CT_MARK: + *dest = READ_ONCE(ct->mark); + return; +#endif +#ifdef CONFIG_NF_CONNTRACK_SECMARK + case NFT_CT_SECMARK: + *dest = ct->secmark; + return; +#endif + case NFT_CT_EXPIRATION: + *dest = jiffies_to_msecs(nf_ct_expires(ct)); + return; + case NFT_CT_HELPER: + if (ct->master == NULL) + goto err; + help = nfct_help(ct->master); + if (help == NULL) + goto err; + helper = rcu_dereference(help->helper); + if (helper == NULL) + goto err; + strncpy((char *)dest, helper->name, NF_CT_HELPER_NAME_LEN); + return; +#ifdef CONFIG_NF_CONNTRACK_LABELS + case NFT_CT_LABELS: { + struct nf_conn_labels *labels = nf_ct_labels_find(ct); + + if (labels) + memcpy(dest, labels->bits, NF_CT_LABELS_MAX_SIZE); + else + memset(dest, 0, NF_CT_LABELS_MAX_SIZE); + return; + } +#endif + case NFT_CT_BYTES: + case NFT_CT_PKTS: { + const struct nf_conn_acct *acct = nf_conn_acct_find(ct); + u64 count = 0; + + if (acct) + count = nft_ct_get_eval_counter(acct->counter, + priv->key, priv->dir); + memcpy(dest, &count, sizeof(count)); + return; + } + case NFT_CT_AVGPKT: { + const struct nf_conn_acct *acct = nf_conn_acct_find(ct); + u64 avgcnt = 0, bcnt = 0, pcnt = 0; + + if (acct) { + pcnt = nft_ct_get_eval_counter(acct->counter, + NFT_CT_PKTS, priv->dir); + bcnt = nft_ct_get_eval_counter(acct->counter, + NFT_CT_BYTES, priv->dir); + if (pcnt != 0) + avgcnt = div64_u64(bcnt, pcnt); + } + + memcpy(dest, &avgcnt, sizeof(avgcnt)); + return; + } + case NFT_CT_L3PROTOCOL: + nft_reg_store8(dest, nf_ct_l3num(ct)); + return; + case NFT_CT_PROTOCOL: + nft_reg_store8(dest, nf_ct_protonum(ct)); + return; +#ifdef CONFIG_NF_CONNTRACK_ZONES + case NFT_CT_ZONE: { + const struct nf_conntrack_zone *zone = nf_ct_zone(ct); + u16 zoneid; + + if (priv->dir < IP_CT_DIR_MAX) + zoneid = nf_ct_zone_id(zone, priv->dir); + else + zoneid = zone->id; + + nft_reg_store16(dest, zoneid); + return; + } +#endif + case NFT_CT_ID: + *dest = nf_ct_get_id(ct); + return; + default: + break; + } + + tuple = &ct->tuplehash[priv->dir].tuple; + switch (priv->key) { + case NFT_CT_SRC: + memcpy(dest, tuple->src.u3.all, + nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16); + return; + case NFT_CT_DST: + memcpy(dest, tuple->dst.u3.all, + nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16); + return; + case NFT_CT_PROTO_SRC: + nft_reg_store16(dest, (__force u16)tuple->src.u.all); + return; + case NFT_CT_PROTO_DST: + nft_reg_store16(dest, (__force u16)tuple->dst.u.all); + return; + case NFT_CT_SRC_IP: + if (nf_ct_l3num(ct) != NFPROTO_IPV4) + goto err; + *dest = (__force __u32)tuple->src.u3.ip; + return; + case NFT_CT_DST_IP: + if (nf_ct_l3num(ct) != NFPROTO_IPV4) + goto err; + *dest = (__force __u32)tuple->dst.u3.ip; + return; + case NFT_CT_SRC_IP6: + if (nf_ct_l3num(ct) != NFPROTO_IPV6) + goto err; + memcpy(dest, tuple->src.u3.ip6, sizeof(struct in6_addr)); + return; + case NFT_CT_DST_IP6: + if (nf_ct_l3num(ct) != NFPROTO_IPV6) + goto err; + memcpy(dest, tuple->dst.u3.ip6, sizeof(struct in6_addr)); + return; + default: + break; + } + return; +err: + regs->verdict.code = NFT_BREAK; +} + +#ifdef CONFIG_NF_CONNTRACK_ZONES +static void nft_ct_set_zone_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + struct nf_conntrack_zone zone = { .dir = NF_CT_DEFAULT_ZONE_DIR }; + const struct nft_ct *priv = nft_expr_priv(expr); + struct sk_buff *skb = pkt->skb; + enum ip_conntrack_info ctinfo; + u16 value = nft_reg_load16(®s->data[priv->sreg]); + struct nf_conn *ct; + + ct = nf_ct_get(skb, &ctinfo); + if (ct) /* already tracked */ + return; + + zone.id = value; + + switch (priv->dir) { + case IP_CT_DIR_ORIGINAL: + zone.dir = NF_CT_ZONE_DIR_ORIG; + break; + case IP_CT_DIR_REPLY: + zone.dir = NF_CT_ZONE_DIR_REPL; + break; + default: + break; + } + + ct = this_cpu_read(nft_ct_pcpu_template); + + if (likely(refcount_read(&ct->ct_general.use) == 1)) { + refcount_inc(&ct->ct_general.use); + nf_ct_zone_add(ct, &zone); + } else { + /* previous skb got queued to userspace, allocate temporary + * one until percpu template can be reused. + */ + ct = nf_ct_tmpl_alloc(nft_net(pkt), &zone, GFP_ATOMIC); + if (!ct) { + regs->verdict.code = NF_DROP; + return; + } + } + + nf_ct_set(skb, ct, IP_CT_NEW); +} +#endif + +static void nft_ct_set_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct *priv = nft_expr_priv(expr); + struct sk_buff *skb = pkt->skb; +#if defined(CONFIG_NF_CONNTRACK_MARK) || defined(CONFIG_NF_CONNTRACK_SECMARK) + u32 value = regs->data[priv->sreg]; +#endif + enum ip_conntrack_info ctinfo; + struct nf_conn *ct; + + ct = nf_ct_get(skb, &ctinfo); + if (ct == NULL || nf_ct_is_template(ct)) + return; + + switch (priv->key) { +#ifdef CONFIG_NF_CONNTRACK_MARK + case NFT_CT_MARK: + if (READ_ONCE(ct->mark) != value) { + WRITE_ONCE(ct->mark, value); + nf_conntrack_event_cache(IPCT_MARK, ct); + } + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_SECMARK + case NFT_CT_SECMARK: + if (ct->secmark != value) { + ct->secmark = value; + nf_conntrack_event_cache(IPCT_SECMARK, ct); + } + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_LABELS + case NFT_CT_LABELS: + nf_connlabels_replace(ct, + ®s->data[priv->sreg], + ®s->data[priv->sreg], + NF_CT_LABELS_MAX_SIZE / sizeof(u32)); + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_EVENTS + case NFT_CT_EVENTMASK: { + struct nf_conntrack_ecache *e = nf_ct_ecache_find(ct); + u32 ctmask = regs->data[priv->sreg]; + + if (e) { + if (e->ctmask != ctmask) + e->ctmask = ctmask; + break; + } + + if (ctmask && !nf_ct_is_confirmed(ct)) + nf_ct_ecache_ext_add(ct, ctmask, 0, GFP_ATOMIC); + break; + } +#endif + default: + break; + } +} + +static const struct nla_policy nft_ct_policy[NFTA_CT_MAX + 1] = { + [NFTA_CT_DREG] = { .type = NLA_U32 }, + [NFTA_CT_KEY] = { .type = NLA_U32 }, + [NFTA_CT_DIRECTION] = { .type = NLA_U8 }, + [NFTA_CT_SREG] = { .type = NLA_U32 }, +}; + +#ifdef CONFIG_NF_CONNTRACK_ZONES +static void nft_ct_tmpl_put_pcpu(void) +{ + struct nf_conn *ct; + int cpu; + + for_each_possible_cpu(cpu) { + ct = per_cpu(nft_ct_pcpu_template, cpu); + if (!ct) + break; + nf_ct_put(ct); + per_cpu(nft_ct_pcpu_template, cpu) = NULL; + } +} + +static bool nft_ct_tmpl_alloc_pcpu(void) +{ + struct nf_conntrack_zone zone = { .id = 0 }; + struct nf_conn *tmp; + int cpu; + + if (nft_ct_pcpu_template_refcnt) + return true; + + for_each_possible_cpu(cpu) { + tmp = nf_ct_tmpl_alloc(&init_net, &zone, GFP_KERNEL); + if (!tmp) { + nft_ct_tmpl_put_pcpu(); + return false; + } + + per_cpu(nft_ct_pcpu_template, cpu) = tmp; + } + + return true; +} +#endif + +static int nft_ct_get_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_ct *priv = nft_expr_priv(expr); + unsigned int len; + int err; + + priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY])); + priv->dir = IP_CT_DIR_MAX; + switch (priv->key) { + case NFT_CT_DIRECTION: + if (tb[NFTA_CT_DIRECTION] != NULL) + return -EINVAL; + len = sizeof(u8); + break; + case NFT_CT_STATE: + case NFT_CT_STATUS: +#ifdef CONFIG_NF_CONNTRACK_MARK + case NFT_CT_MARK: +#endif +#ifdef CONFIG_NF_CONNTRACK_SECMARK + case NFT_CT_SECMARK: +#endif + case NFT_CT_EXPIRATION: + if (tb[NFTA_CT_DIRECTION] != NULL) + return -EINVAL; + len = sizeof(u32); + break; +#ifdef CONFIG_NF_CONNTRACK_LABELS + case NFT_CT_LABELS: + if (tb[NFTA_CT_DIRECTION] != NULL) + return -EINVAL; + len = NF_CT_LABELS_MAX_SIZE; + break; +#endif + case NFT_CT_HELPER: + if (tb[NFTA_CT_DIRECTION] != NULL) + return -EINVAL; + len = NF_CT_HELPER_NAME_LEN; + break; + + case NFT_CT_L3PROTOCOL: + case NFT_CT_PROTOCOL: + /* For compatibility, do not report error if NFTA_CT_DIRECTION + * attribute is specified. + */ + len = sizeof(u8); + break; + case NFT_CT_SRC: + case NFT_CT_DST: + if (tb[NFTA_CT_DIRECTION] == NULL) + return -EINVAL; + + switch (ctx->family) { + case NFPROTO_IPV4: + len = sizeof_field(struct nf_conntrack_tuple, + src.u3.ip); + break; + case NFPROTO_IPV6: + case NFPROTO_INET: + len = sizeof_field(struct nf_conntrack_tuple, + src.u3.ip6); + break; + default: + return -EAFNOSUPPORT; + } + break; + case NFT_CT_SRC_IP: + case NFT_CT_DST_IP: + if (tb[NFTA_CT_DIRECTION] == NULL) + return -EINVAL; + + len = sizeof_field(struct nf_conntrack_tuple, src.u3.ip); + break; + case NFT_CT_SRC_IP6: + case NFT_CT_DST_IP6: + if (tb[NFTA_CT_DIRECTION] == NULL) + return -EINVAL; + + len = sizeof_field(struct nf_conntrack_tuple, src.u3.ip6); + break; + case NFT_CT_PROTO_SRC: + case NFT_CT_PROTO_DST: + if (tb[NFTA_CT_DIRECTION] == NULL) + return -EINVAL; + len = sizeof_field(struct nf_conntrack_tuple, src.u.all); + break; + case NFT_CT_BYTES: + case NFT_CT_PKTS: + case NFT_CT_AVGPKT: + len = sizeof(u64); + break; +#ifdef CONFIG_NF_CONNTRACK_ZONES + case NFT_CT_ZONE: + len = sizeof(u16); + break; +#endif + case NFT_CT_ID: + len = sizeof(u32); + break; + default: + return -EOPNOTSUPP; + } + + if (tb[NFTA_CT_DIRECTION] != NULL) { + priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]); + switch (priv->dir) { + case IP_CT_DIR_ORIGINAL: + case IP_CT_DIR_REPLY: + break; + default: + return -EINVAL; + } + } + + priv->len = len; + err = nft_parse_register_store(ctx, tb[NFTA_CT_DREG], &priv->dreg, NULL, + NFT_DATA_VALUE, len); + if (err < 0) + return err; + + err = nf_ct_netns_get(ctx->net, ctx->family); + if (err < 0) + return err; + + if (priv->key == NFT_CT_BYTES || + priv->key == NFT_CT_PKTS || + priv->key == NFT_CT_AVGPKT) + nf_ct_set_acct(ctx->net, true); + + return 0; +} + +static void __nft_ct_set_destroy(const struct nft_ctx *ctx, struct nft_ct *priv) +{ + switch (priv->key) { +#ifdef CONFIG_NF_CONNTRACK_LABELS + case NFT_CT_LABELS: + nf_connlabels_put(ctx->net); + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_ZONES + case NFT_CT_ZONE: + mutex_lock(&nft_ct_pcpu_mutex); + if (--nft_ct_pcpu_template_refcnt == 0) + nft_ct_tmpl_put_pcpu(); + mutex_unlock(&nft_ct_pcpu_mutex); + break; +#endif + default: + break; + } +} + +static int nft_ct_set_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_ct *priv = nft_expr_priv(expr); + unsigned int len; + int err; + + priv->dir = IP_CT_DIR_MAX; + priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY])); + switch (priv->key) { +#ifdef CONFIG_NF_CONNTRACK_MARK + case NFT_CT_MARK: + if (tb[NFTA_CT_DIRECTION]) + return -EINVAL; + len = sizeof_field(struct nf_conn, mark); + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_LABELS + case NFT_CT_LABELS: + if (tb[NFTA_CT_DIRECTION]) + return -EINVAL; + len = NF_CT_LABELS_MAX_SIZE; + err = nf_connlabels_get(ctx->net, (len * BITS_PER_BYTE) - 1); + if (err) + return err; + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_ZONES + case NFT_CT_ZONE: + mutex_lock(&nft_ct_pcpu_mutex); + if (!nft_ct_tmpl_alloc_pcpu()) { + mutex_unlock(&nft_ct_pcpu_mutex); + return -ENOMEM; + } + nft_ct_pcpu_template_refcnt++; + mutex_unlock(&nft_ct_pcpu_mutex); + len = sizeof(u16); + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_EVENTS + case NFT_CT_EVENTMASK: + if (tb[NFTA_CT_DIRECTION]) + return -EINVAL; + len = sizeof(u32); + break; +#endif +#ifdef CONFIG_NF_CONNTRACK_SECMARK + case NFT_CT_SECMARK: + if (tb[NFTA_CT_DIRECTION]) + return -EINVAL; + len = sizeof(u32); + break; +#endif + default: + return -EOPNOTSUPP; + } + + if (tb[NFTA_CT_DIRECTION]) { + priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]); + switch (priv->dir) { + case IP_CT_DIR_ORIGINAL: + case IP_CT_DIR_REPLY: + break; + default: + err = -EINVAL; + goto err1; + } + } + + priv->len = len; + err = nft_parse_register_load(tb[NFTA_CT_SREG], &priv->sreg, len); + if (err < 0) + goto err1; + + err = nf_ct_netns_get(ctx->net, ctx->family); + if (err < 0) + goto err1; + + return 0; + +err1: + __nft_ct_set_destroy(ctx, priv); + return err; +} + +static void nft_ct_get_destroy(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + nf_ct_netns_put(ctx->net, ctx->family); +} + +static void nft_ct_set_destroy(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + struct nft_ct *priv = nft_expr_priv(expr); + + __nft_ct_set_destroy(ctx, priv); + nf_ct_netns_put(ctx->net, ctx->family); +} + +static int nft_ct_get_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_ct *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_CT_DREG, priv->dreg)) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key))) + goto nla_put_failure; + + switch (priv->key) { + case NFT_CT_SRC: + case NFT_CT_DST: + case NFT_CT_SRC_IP: + case NFT_CT_DST_IP: + case NFT_CT_SRC_IP6: + case NFT_CT_DST_IP6: + case NFT_CT_PROTO_SRC: + case NFT_CT_PROTO_DST: + if (nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir)) + goto nla_put_failure; + break; + case NFT_CT_BYTES: + case NFT_CT_PKTS: + case NFT_CT_AVGPKT: + case NFT_CT_ZONE: + if (priv->dir < IP_CT_DIR_MAX && + nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir)) + goto nla_put_failure; + break; + default: + break; + } + + return 0; + +nla_put_failure: + return -1; +} + +static bool nft_ct_get_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_ct *priv = nft_expr_priv(expr); + const struct nft_ct *ct; + + if (!nft_reg_track_cmp(track, expr, priv->dreg)) { + nft_reg_track_update(track, expr, priv->dreg, priv->len); + return false; + } + + ct = nft_expr_priv(track->regs[priv->dreg].selector); + if (priv->key != ct->key) { + nft_reg_track_update(track, expr, priv->dreg, priv->len); + return false; + } + + if (!track->regs[priv->dreg].bitwise) + return true; + + return nft_expr_reduce_bitwise(track, expr); +} + +static int nft_ct_set_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_ct *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_CT_SREG, priv->sreg)) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key))) + goto nla_put_failure; + + switch (priv->key) { + case NFT_CT_ZONE: + if (priv->dir < IP_CT_DIR_MAX && + nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir)) + goto nla_put_failure; + break; + default: + break; + } + + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_ct_type; +static const struct nft_expr_ops nft_ct_get_ops = { + .type = &nft_ct_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)), + .eval = nft_ct_get_eval, + .init = nft_ct_get_init, + .destroy = nft_ct_get_destroy, + .dump = nft_ct_get_dump, + .reduce = nft_ct_get_reduce, +}; + +static bool nft_ct_set_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + int i; + + for (i = 0; i < NFT_REG32_NUM; i++) { + if (!track->regs[i].selector) + continue; + + if (track->regs[i].selector->ops != &nft_ct_get_ops) + continue; + + __nft_reg_track_cancel(track, i); + } + + return false; +} + +static const struct nft_expr_ops nft_ct_set_ops = { + .type = &nft_ct_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)), + .eval = nft_ct_set_eval, + .init = nft_ct_set_init, + .destroy = nft_ct_set_destroy, + .dump = nft_ct_set_dump, + .reduce = nft_ct_set_reduce, +}; + +#ifdef CONFIG_NF_CONNTRACK_ZONES +static const struct nft_expr_ops nft_ct_set_zone_ops = { + .type = &nft_ct_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_ct)), + .eval = nft_ct_set_zone_eval, + .init = nft_ct_set_init, + .destroy = nft_ct_set_destroy, + .dump = nft_ct_set_dump, + .reduce = nft_ct_set_reduce, +}; +#endif + +static const struct nft_expr_ops * +nft_ct_select_ops(const struct nft_ctx *ctx, + const struct nlattr * const tb[]) +{ + if (tb[NFTA_CT_KEY] == NULL) + return ERR_PTR(-EINVAL); + + if (tb[NFTA_CT_DREG] && tb[NFTA_CT_SREG]) + return ERR_PTR(-EINVAL); + + if (tb[NFTA_CT_DREG]) + return &nft_ct_get_ops; + + if (tb[NFTA_CT_SREG]) { +#ifdef CONFIG_NF_CONNTRACK_ZONES + if (nla_get_be32(tb[NFTA_CT_KEY]) == htonl(NFT_CT_ZONE)) + return &nft_ct_set_zone_ops; +#endif + return &nft_ct_set_ops; + } + + return ERR_PTR(-EINVAL); +} + +static struct nft_expr_type nft_ct_type __read_mostly = { + .name = "ct", + .select_ops = nft_ct_select_ops, + .policy = nft_ct_policy, + .maxattr = NFTA_CT_MAX, + .owner = THIS_MODULE, +}; + +static void nft_notrack_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + struct sk_buff *skb = pkt->skb; + enum ip_conntrack_info ctinfo; + struct nf_conn *ct; + + ct = nf_ct_get(pkt->skb, &ctinfo); + /* Previously seen (loopback or untracked)? Ignore. */ + if (ct || ctinfo == IP_CT_UNTRACKED) + return; + + nf_ct_set(skb, ct, IP_CT_UNTRACKED); +} + +static struct nft_expr_type nft_notrack_type; +static const struct nft_expr_ops nft_notrack_ops = { + .type = &nft_notrack_type, + .size = NFT_EXPR_SIZE(0), + .eval = nft_notrack_eval, + .reduce = NFT_REDUCE_READONLY, +}; + +static struct nft_expr_type nft_notrack_type __read_mostly = { + .name = "notrack", + .ops = &nft_notrack_ops, + .owner = THIS_MODULE, +}; + +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT +static int +nft_ct_timeout_parse_policy(void *timeouts, + const struct nf_conntrack_l4proto *l4proto, + struct net *net, const struct nlattr *attr) +{ + struct nlattr **tb; + int ret = 0; + + tb = kcalloc(l4proto->ctnl_timeout.nlattr_max + 1, sizeof(*tb), + GFP_KERNEL); + + if (!tb) + return -ENOMEM; + + ret = nla_parse_nested_deprecated(tb, + l4proto->ctnl_timeout.nlattr_max, + attr, + l4proto->ctnl_timeout.nla_policy, + NULL); + if (ret < 0) + goto err; + + ret = l4proto->ctnl_timeout.nlattr_to_obj(tb, net, timeouts); + +err: + kfree(tb); + return ret; +} + +struct nft_ct_timeout_obj { + struct nf_ct_timeout *timeout; + u8 l4proto; +}; + +static void nft_ct_timeout_obj_eval(struct nft_object *obj, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb); + struct nf_conn_timeout *timeout; + const unsigned int *values; + + if (priv->l4proto != pkt->tprot) + return; + + if (!ct || nf_ct_is_template(ct) || nf_ct_is_confirmed(ct)) + return; + + timeout = nf_ct_timeout_find(ct); + if (!timeout) { + timeout = nf_ct_timeout_ext_add(ct, priv->timeout, GFP_ATOMIC); + if (!timeout) { + regs->verdict.code = NF_DROP; + return; + } + } + + rcu_assign_pointer(timeout->timeout, priv->timeout); + + /* adjust the timeout as per 'new' state. ct is unconfirmed, + * so the current timestamp must not be added. + */ + values = nf_ct_timeout_data(timeout); + if (values) + nf_ct_refresh(ct, pkt->skb, values[0]); +} + +static int nft_ct_timeout_obj_init(const struct nft_ctx *ctx, + const struct nlattr * const tb[], + struct nft_object *obj) +{ + struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + const struct nf_conntrack_l4proto *l4proto; + struct nf_ct_timeout *timeout; + int l3num = ctx->family; + __u8 l4num; + int ret; + + if (!tb[NFTA_CT_TIMEOUT_L4PROTO] || + !tb[NFTA_CT_TIMEOUT_DATA]) + return -EINVAL; + + if (tb[NFTA_CT_TIMEOUT_L3PROTO]) + l3num = ntohs(nla_get_be16(tb[NFTA_CT_TIMEOUT_L3PROTO])); + + l4num = nla_get_u8(tb[NFTA_CT_TIMEOUT_L4PROTO]); + priv->l4proto = l4num; + + l4proto = nf_ct_l4proto_find(l4num); + + if (l4proto->l4proto != l4num) { + ret = -EOPNOTSUPP; + goto err_proto_put; + } + + timeout = kzalloc(sizeof(struct nf_ct_timeout) + + l4proto->ctnl_timeout.obj_size, GFP_KERNEL); + if (timeout == NULL) { + ret = -ENOMEM; + goto err_proto_put; + } + + ret = nft_ct_timeout_parse_policy(&timeout->data, l4proto, ctx->net, + tb[NFTA_CT_TIMEOUT_DATA]); + if (ret < 0) + goto err_free_timeout; + + timeout->l3num = l3num; + timeout->l4proto = l4proto; + + ret = nf_ct_netns_get(ctx->net, ctx->family); + if (ret < 0) + goto err_free_timeout; + + priv->timeout = timeout; + return 0; + +err_free_timeout: + kfree(timeout); +err_proto_put: + return ret; +} + +static void nft_ct_timeout_obj_destroy(const struct nft_ctx *ctx, + struct nft_object *obj) +{ + struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + struct nf_ct_timeout *timeout = priv->timeout; + + nf_ct_untimeout(ctx->net, timeout); + nf_ct_netns_put(ctx->net, ctx->family); + kfree(priv->timeout); +} + +static int nft_ct_timeout_obj_dump(struct sk_buff *skb, + struct nft_object *obj, bool reset) +{ + const struct nft_ct_timeout_obj *priv = nft_obj_data(obj); + const struct nf_ct_timeout *timeout = priv->timeout; + struct nlattr *nest_params; + int ret; + + if (nla_put_u8(skb, NFTA_CT_TIMEOUT_L4PROTO, timeout->l4proto->l4proto) || + nla_put_be16(skb, NFTA_CT_TIMEOUT_L3PROTO, htons(timeout->l3num))) + return -1; + + nest_params = nla_nest_start(skb, NFTA_CT_TIMEOUT_DATA); + if (!nest_params) + return -1; + + ret = timeout->l4proto->ctnl_timeout.obj_to_nlattr(skb, &timeout->data); + if (ret < 0) + return -1; + nla_nest_end(skb, nest_params); + return 0; +} + +static const struct nla_policy nft_ct_timeout_policy[NFTA_CT_TIMEOUT_MAX + 1] = { + [NFTA_CT_TIMEOUT_L3PROTO] = {.type = NLA_U16 }, + [NFTA_CT_TIMEOUT_L4PROTO] = {.type = NLA_U8 }, + [NFTA_CT_TIMEOUT_DATA] = {.type = NLA_NESTED }, +}; + +static struct nft_object_type nft_ct_timeout_obj_type; + +static const struct nft_object_ops nft_ct_timeout_obj_ops = { + .type = &nft_ct_timeout_obj_type, + .size = sizeof(struct nft_ct_timeout_obj), + .eval = nft_ct_timeout_obj_eval, + .init = nft_ct_timeout_obj_init, + .destroy = nft_ct_timeout_obj_destroy, + .dump = nft_ct_timeout_obj_dump, +}; + +static struct nft_object_type nft_ct_timeout_obj_type __read_mostly = { + .type = NFT_OBJECT_CT_TIMEOUT, + .ops = &nft_ct_timeout_obj_ops, + .maxattr = NFTA_CT_TIMEOUT_MAX, + .policy = nft_ct_timeout_policy, + .owner = THIS_MODULE, +}; +#endif /* CONFIG_NF_CONNTRACK_TIMEOUT */ + +static int nft_ct_helper_obj_init(const struct nft_ctx *ctx, + const struct nlattr * const tb[], + struct nft_object *obj) +{ + struct nft_ct_helper_obj *priv = nft_obj_data(obj); + struct nf_conntrack_helper *help4, *help6; + char name[NF_CT_HELPER_NAME_LEN]; + int family = ctx->family; + int err; + + if (!tb[NFTA_CT_HELPER_NAME] || !tb[NFTA_CT_HELPER_L4PROTO]) + return -EINVAL; + + priv->l4proto = nla_get_u8(tb[NFTA_CT_HELPER_L4PROTO]); + if (!priv->l4proto) + return -ENOENT; + + nla_strscpy(name, tb[NFTA_CT_HELPER_NAME], sizeof(name)); + + if (tb[NFTA_CT_HELPER_L3PROTO]) + family = ntohs(nla_get_be16(tb[NFTA_CT_HELPER_L3PROTO])); + + help4 = NULL; + help6 = NULL; + + switch (family) { + case NFPROTO_IPV4: + if (ctx->family == NFPROTO_IPV6) + return -EINVAL; + + help4 = nf_conntrack_helper_try_module_get(name, family, + priv->l4proto); + break; + case NFPROTO_IPV6: + if (ctx->family == NFPROTO_IPV4) + return -EINVAL; + + help6 = nf_conntrack_helper_try_module_get(name, family, + priv->l4proto); + break; + case NFPROTO_NETDEV: + case NFPROTO_BRIDGE: + case NFPROTO_INET: + help4 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV4, + priv->l4proto); + help6 = nf_conntrack_helper_try_module_get(name, NFPROTO_IPV6, + priv->l4proto); + break; + default: + return -EAFNOSUPPORT; + } + + /* && is intentional; only error if INET found neither ipv4 or ipv6 */ + if (!help4 && !help6) + return -ENOENT; + + priv->helper4 = help4; + priv->helper6 = help6; + + err = nf_ct_netns_get(ctx->net, ctx->family); + if (err < 0) + goto err_put_helper; + + return 0; + +err_put_helper: + if (priv->helper4) + nf_conntrack_helper_put(priv->helper4); + if (priv->helper6) + nf_conntrack_helper_put(priv->helper6); + return err; +} + +static void nft_ct_helper_obj_destroy(const struct nft_ctx *ctx, + struct nft_object *obj) +{ + struct nft_ct_helper_obj *priv = nft_obj_data(obj); + + if (priv->helper4) + nf_conntrack_helper_put(priv->helper4); + if (priv->helper6) + nf_conntrack_helper_put(priv->helper6); + + nf_ct_netns_put(ctx->net, ctx->family); +} + +static void nft_ct_helper_obj_eval(struct nft_object *obj, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct_helper_obj *priv = nft_obj_data(obj); + struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb); + struct nf_conntrack_helper *to_assign = NULL; + struct nf_conn_help *help; + + if (!ct || + nf_ct_is_confirmed(ct) || + nf_ct_is_template(ct) || + priv->l4proto != nf_ct_protonum(ct)) + return; + + switch (nf_ct_l3num(ct)) { + case NFPROTO_IPV4: + to_assign = priv->helper4; + break; + case NFPROTO_IPV6: + to_assign = priv->helper6; + break; + default: + WARN_ON_ONCE(1); + return; + } + + if (!to_assign) + return; + + if (test_bit(IPS_HELPER_BIT, &ct->status)) + return; + + help = nf_ct_helper_ext_add(ct, GFP_ATOMIC); + if (help) { + rcu_assign_pointer(help->helper, to_assign); + set_bit(IPS_HELPER_BIT, &ct->status); + } +} + +static int nft_ct_helper_obj_dump(struct sk_buff *skb, + struct nft_object *obj, bool reset) +{ + const struct nft_ct_helper_obj *priv = nft_obj_data(obj); + const struct nf_conntrack_helper *helper; + u16 family; + + if (priv->helper4 && priv->helper6) { + family = NFPROTO_INET; + helper = priv->helper4; + } else if (priv->helper6) { + family = NFPROTO_IPV6; + helper = priv->helper6; + } else { + family = NFPROTO_IPV4; + helper = priv->helper4; + } + + if (nla_put_string(skb, NFTA_CT_HELPER_NAME, helper->name)) + return -1; + + if (nla_put_u8(skb, NFTA_CT_HELPER_L4PROTO, priv->l4proto)) + return -1; + + if (nla_put_be16(skb, NFTA_CT_HELPER_L3PROTO, htons(family))) + return -1; + + return 0; +} + +static const struct nla_policy nft_ct_helper_policy[NFTA_CT_HELPER_MAX + 1] = { + [NFTA_CT_HELPER_NAME] = { .type = NLA_STRING, + .len = NF_CT_HELPER_NAME_LEN - 1 }, + [NFTA_CT_HELPER_L3PROTO] = { .type = NLA_U16 }, + [NFTA_CT_HELPER_L4PROTO] = { .type = NLA_U8 }, +}; + +static struct nft_object_type nft_ct_helper_obj_type; +static const struct nft_object_ops nft_ct_helper_obj_ops = { + .type = &nft_ct_helper_obj_type, + .size = sizeof(struct nft_ct_helper_obj), + .eval = nft_ct_helper_obj_eval, + .init = nft_ct_helper_obj_init, + .destroy = nft_ct_helper_obj_destroy, + .dump = nft_ct_helper_obj_dump, +}; + +static struct nft_object_type nft_ct_helper_obj_type __read_mostly = { + .type = NFT_OBJECT_CT_HELPER, + .ops = &nft_ct_helper_obj_ops, + .maxattr = NFTA_CT_HELPER_MAX, + .policy = nft_ct_helper_policy, + .owner = THIS_MODULE, +}; + +struct nft_ct_expect_obj { + u16 l3num; + __be16 dport; + u8 l4proto; + u8 size; + u32 timeout; +}; + +static int nft_ct_expect_obj_init(const struct nft_ctx *ctx, + const struct nlattr * const tb[], + struct nft_object *obj) +{ + struct nft_ct_expect_obj *priv = nft_obj_data(obj); + + if (!tb[NFTA_CT_EXPECT_L4PROTO] || + !tb[NFTA_CT_EXPECT_DPORT] || + !tb[NFTA_CT_EXPECT_TIMEOUT] || + !tb[NFTA_CT_EXPECT_SIZE]) + return -EINVAL; + + priv->l3num = ctx->family; + if (tb[NFTA_CT_EXPECT_L3PROTO]) + priv->l3num = ntohs(nla_get_be16(tb[NFTA_CT_EXPECT_L3PROTO])); + + priv->l4proto = nla_get_u8(tb[NFTA_CT_EXPECT_L4PROTO]); + priv->dport = nla_get_be16(tb[NFTA_CT_EXPECT_DPORT]); + priv->timeout = nla_get_u32(tb[NFTA_CT_EXPECT_TIMEOUT]); + priv->size = nla_get_u8(tb[NFTA_CT_EXPECT_SIZE]); + + return nf_ct_netns_get(ctx->net, ctx->family); +} + +static void nft_ct_expect_obj_destroy(const struct nft_ctx *ctx, + struct nft_object *obj) +{ + nf_ct_netns_put(ctx->net, ctx->family); +} + +static int nft_ct_expect_obj_dump(struct sk_buff *skb, + struct nft_object *obj, bool reset) +{ + const struct nft_ct_expect_obj *priv = nft_obj_data(obj); + + if (nla_put_be16(skb, NFTA_CT_EXPECT_L3PROTO, htons(priv->l3num)) || + nla_put_u8(skb, NFTA_CT_EXPECT_L4PROTO, priv->l4proto) || + nla_put_be16(skb, NFTA_CT_EXPECT_DPORT, priv->dport) || + nla_put_u32(skb, NFTA_CT_EXPECT_TIMEOUT, priv->timeout) || + nla_put_u8(skb, NFTA_CT_EXPECT_SIZE, priv->size)) + return -1; + + return 0; +} + +static void nft_ct_expect_obj_eval(struct nft_object *obj, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_ct_expect_obj *priv = nft_obj_data(obj); + struct nf_conntrack_expect *exp; + enum ip_conntrack_info ctinfo; + struct nf_conn_help *help; + enum ip_conntrack_dir dir; + u16 l3num = priv->l3num; + struct nf_conn *ct; + + ct = nf_ct_get(pkt->skb, &ctinfo); + if (!ct || nf_ct_is_confirmed(ct) || nf_ct_is_template(ct)) { + regs->verdict.code = NFT_BREAK; + return; + } + dir = CTINFO2DIR(ctinfo); + + help = nfct_help(ct); + if (!help) + help = nf_ct_helper_ext_add(ct, GFP_ATOMIC); + if (!help) { + regs->verdict.code = NF_DROP; + return; + } + + if (help->expecting[NF_CT_EXPECT_CLASS_DEFAULT] >= priv->size) { + regs->verdict.code = NFT_BREAK; + return; + } + if (l3num == NFPROTO_INET) + l3num = nf_ct_l3num(ct); + + exp = nf_ct_expect_alloc(ct); + if (exp == NULL) { + regs->verdict.code = NF_DROP; + return; + } + nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, l3num, + &ct->tuplehash[!dir].tuple.src.u3, + &ct->tuplehash[!dir].tuple.dst.u3, + priv->l4proto, NULL, &priv->dport); + exp->timeout.expires = jiffies + priv->timeout * HZ; + + if (nf_ct_expect_related(exp, 0) != 0) + regs->verdict.code = NF_DROP; +} + +static const struct nla_policy nft_ct_expect_policy[NFTA_CT_EXPECT_MAX + 1] = { + [NFTA_CT_EXPECT_L3PROTO] = { .type = NLA_U16 }, + [NFTA_CT_EXPECT_L4PROTO] = { .type = NLA_U8 }, + [NFTA_CT_EXPECT_DPORT] = { .type = NLA_U16 }, + [NFTA_CT_EXPECT_TIMEOUT] = { .type = NLA_U32 }, + [NFTA_CT_EXPECT_SIZE] = { .type = NLA_U8 }, +}; + +static struct nft_object_type nft_ct_expect_obj_type; + +static const struct nft_object_ops nft_ct_expect_obj_ops = { + .type = &nft_ct_expect_obj_type, + .size = sizeof(struct nft_ct_expect_obj), + .eval = nft_ct_expect_obj_eval, + .init = nft_ct_expect_obj_init, + .destroy = nft_ct_expect_obj_destroy, + .dump = nft_ct_expect_obj_dump, +}; + +static struct nft_object_type nft_ct_expect_obj_type __read_mostly = { + .type = NFT_OBJECT_CT_EXPECT, + .ops = &nft_ct_expect_obj_ops, + .maxattr = NFTA_CT_EXPECT_MAX, + .policy = nft_ct_expect_policy, + .owner = THIS_MODULE, +}; + +static int __init nft_ct_module_init(void) +{ + int err; + + BUILD_BUG_ON(NF_CT_LABELS_MAX_SIZE > NFT_REG_SIZE); + + err = nft_register_expr(&nft_ct_type); + if (err < 0) + return err; + + err = nft_register_expr(&nft_notrack_type); + if (err < 0) + goto err1; + + err = nft_register_obj(&nft_ct_helper_obj_type); + if (err < 0) + goto err2; + + err = nft_register_obj(&nft_ct_expect_obj_type); + if (err < 0) + goto err3; +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT + err = nft_register_obj(&nft_ct_timeout_obj_type); + if (err < 0) + goto err4; +#endif + return 0; + +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT +err4: + nft_unregister_obj(&nft_ct_expect_obj_type); +#endif +err3: + nft_unregister_obj(&nft_ct_helper_obj_type); +err2: + nft_unregister_expr(&nft_notrack_type); +err1: + nft_unregister_expr(&nft_ct_type); + return err; +} + +static void __exit nft_ct_module_exit(void) +{ +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT + nft_unregister_obj(&nft_ct_timeout_obj_type); +#endif + nft_unregister_obj(&nft_ct_expect_obj_type); + nft_unregister_obj(&nft_ct_helper_obj_type); + nft_unregister_expr(&nft_notrack_type); + nft_unregister_expr(&nft_ct_type); +} + +module_init(nft_ct_module_init); +module_exit(nft_ct_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); +MODULE_ALIAS_NFT_EXPR("ct"); +MODULE_ALIAS_NFT_EXPR("notrack"); +MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_HELPER); +MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_TIMEOUT); +MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_CT_EXPECT); +MODULE_DESCRIPTION("Netfilter nf_tables conntrack module"); |