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Diffstat (limited to 'net/netfilter/nf_conntrack_bpf.c')
-rw-r--r--net/netfilter/nf_conntrack_bpf.c365
1 files changed, 276 insertions, 89 deletions
diff --git a/net/netfilter/nf_conntrack_bpf.c b/net/netfilter/nf_conntrack_bpf.c
index bc4d5cd63a94..1cd87b28c9b0 100644
--- a/net/netfilter/nf_conntrack_bpf.c
+++ b/net/netfilter/nf_conntrack_bpf.c
@@ -55,57 +55,131 @@ enum {
NF_BPF_CT_OPTS_SZ = 12,
};
-static struct nf_conn *__bpf_nf_ct_lookup(struct net *net,
- struct bpf_sock_tuple *bpf_tuple,
- u32 tuple_len, u8 protonum,
- s32 netns_id, u8 *dir)
+static int bpf_nf_ct_tuple_parse(struct bpf_sock_tuple *bpf_tuple,
+ u32 tuple_len, u8 protonum, u8 dir,
+ struct nf_conntrack_tuple *tuple)
{
- struct nf_conntrack_tuple_hash *hash;
- struct nf_conntrack_tuple tuple;
- struct nf_conn *ct;
+ union nf_inet_addr *src = dir ? &tuple->dst.u3 : &tuple->src.u3;
+ union nf_inet_addr *dst = dir ? &tuple->src.u3 : &tuple->dst.u3;
+ union nf_conntrack_man_proto *sport = dir ? (void *)&tuple->dst.u
+ : &tuple->src.u;
+ union nf_conntrack_man_proto *dport = dir ? &tuple->src.u
+ : (void *)&tuple->dst.u;
if (unlikely(protonum != IPPROTO_TCP && protonum != IPPROTO_UDP))
- return ERR_PTR(-EPROTO);
- if (unlikely(netns_id < BPF_F_CURRENT_NETNS))
- return ERR_PTR(-EINVAL);
+ return -EPROTO;
+
+ memset(tuple, 0, sizeof(*tuple));
- memset(&tuple, 0, sizeof(tuple));
switch (tuple_len) {
case sizeof(bpf_tuple->ipv4):
- tuple.src.l3num = AF_INET;
- tuple.src.u3.ip = bpf_tuple->ipv4.saddr;
- tuple.src.u.tcp.port = bpf_tuple->ipv4.sport;
- tuple.dst.u3.ip = bpf_tuple->ipv4.daddr;
- tuple.dst.u.tcp.port = bpf_tuple->ipv4.dport;
+ tuple->src.l3num = AF_INET;
+ src->ip = bpf_tuple->ipv4.saddr;
+ sport->tcp.port = bpf_tuple->ipv4.sport;
+ dst->ip = bpf_tuple->ipv4.daddr;
+ dport->tcp.port = bpf_tuple->ipv4.dport;
break;
case sizeof(bpf_tuple->ipv6):
- tuple.src.l3num = AF_INET6;
- memcpy(tuple.src.u3.ip6, bpf_tuple->ipv6.saddr, sizeof(bpf_tuple->ipv6.saddr));
- tuple.src.u.tcp.port = bpf_tuple->ipv6.sport;
- memcpy(tuple.dst.u3.ip6, bpf_tuple->ipv6.daddr, sizeof(bpf_tuple->ipv6.daddr));
- tuple.dst.u.tcp.port = bpf_tuple->ipv6.dport;
+ tuple->src.l3num = AF_INET6;
+ memcpy(src->ip6, bpf_tuple->ipv6.saddr, sizeof(bpf_tuple->ipv6.saddr));
+ sport->tcp.port = bpf_tuple->ipv6.sport;
+ memcpy(dst->ip6, bpf_tuple->ipv6.daddr, sizeof(bpf_tuple->ipv6.daddr));
+ dport->tcp.port = bpf_tuple->ipv6.dport;
break;
default:
- return ERR_PTR(-EAFNOSUPPORT);
+ return -EAFNOSUPPORT;
+ }
+ tuple->dst.protonum = protonum;
+ tuple->dst.dir = dir;
+
+ return 0;
+}
+
+static struct nf_conn *
+__bpf_nf_ct_alloc_entry(struct net *net, struct bpf_sock_tuple *bpf_tuple,
+ u32 tuple_len, struct bpf_ct_opts *opts, u32 opts_len,
+ u32 timeout)
+{
+ struct nf_conntrack_tuple otuple, rtuple;
+ struct nf_conn *ct;
+ int err;
+
+ if (!opts || !bpf_tuple || opts->reserved[0] || opts->reserved[1] ||
+ opts_len != NF_BPF_CT_OPTS_SZ)
+ return ERR_PTR(-EINVAL);
+
+ if (unlikely(opts->netns_id < BPF_F_CURRENT_NETNS))
+ return ERR_PTR(-EINVAL);
+
+ err = bpf_nf_ct_tuple_parse(bpf_tuple, tuple_len, opts->l4proto,
+ IP_CT_DIR_ORIGINAL, &otuple);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ err = bpf_nf_ct_tuple_parse(bpf_tuple, tuple_len, opts->l4proto,
+ IP_CT_DIR_REPLY, &rtuple);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ if (opts->netns_id >= 0) {
+ net = get_net_ns_by_id(net, opts->netns_id);
+ if (unlikely(!net))
+ return ERR_PTR(-ENONET);
}
- tuple.dst.protonum = protonum;
+ ct = nf_conntrack_alloc(net, &nf_ct_zone_dflt, &otuple, &rtuple,
+ GFP_ATOMIC);
+ if (IS_ERR(ct))
+ goto out;
+
+ memset(&ct->proto, 0, sizeof(ct->proto));
+ __nf_ct_set_timeout(ct, timeout * HZ);
+ ct->status |= IPS_CONFIRMED;
+
+out:
+ if (opts->netns_id >= 0)
+ put_net(net);
+
+ return ct;
+}
+
+static struct nf_conn *__bpf_nf_ct_lookup(struct net *net,
+ struct bpf_sock_tuple *bpf_tuple,
+ u32 tuple_len, struct bpf_ct_opts *opts,
+ u32 opts_len)
+{
+ struct nf_conntrack_tuple_hash *hash;
+ struct nf_conntrack_tuple tuple;
+ struct nf_conn *ct;
+ int err;
+
+ if (!opts || !bpf_tuple || opts->reserved[0] || opts->reserved[1] ||
+ opts_len != NF_BPF_CT_OPTS_SZ)
+ return ERR_PTR(-EINVAL);
+ if (unlikely(opts->l4proto != IPPROTO_TCP && opts->l4proto != IPPROTO_UDP))
+ return ERR_PTR(-EPROTO);
+ if (unlikely(opts->netns_id < BPF_F_CURRENT_NETNS))
+ return ERR_PTR(-EINVAL);
+
+ err = bpf_nf_ct_tuple_parse(bpf_tuple, tuple_len, opts->l4proto,
+ IP_CT_DIR_ORIGINAL, &tuple);
+ if (err < 0)
+ return ERR_PTR(err);
- if (netns_id >= 0) {
- net = get_net_ns_by_id(net, netns_id);
+ if (opts->netns_id >= 0) {
+ net = get_net_ns_by_id(net, opts->netns_id);
if (unlikely(!net))
return ERR_PTR(-ENONET);
}
hash = nf_conntrack_find_get(net, &nf_ct_zone_dflt, &tuple);
- if (netns_id >= 0)
+ if (opts->netns_id >= 0)
put_net(net);
if (!hash)
return ERR_PTR(-ENOENT);
ct = nf_ct_tuplehash_to_ctrack(hash);
- if (dir)
- *dir = NF_CT_DIRECTION(hash);
+ opts->dir = NF_CT_DIRECTION(hash);
return ct;
}
@@ -114,6 +188,43 @@ __diag_push();
__diag_ignore_all("-Wmissing-prototypes",
"Global functions as their definitions will be in nf_conntrack BTF");
+struct nf_conn___init {
+ struct nf_conn ct;
+};
+
+/* bpf_xdp_ct_alloc - Allocate a new CT entry
+ *
+ * Parameters:
+ * @xdp_ctx - Pointer to ctx (xdp_md) in XDP program
+ * Cannot be NULL
+ * @bpf_tuple - Pointer to memory representing the tuple to look up
+ * Cannot be NULL
+ * @tuple__sz - Length of the tuple structure
+ * Must be one of sizeof(bpf_tuple->ipv4) or
+ * sizeof(bpf_tuple->ipv6)
+ * @opts - Additional options for allocation (documented above)
+ * Cannot be NULL
+ * @opts__sz - Length of the bpf_ct_opts structure
+ * Must be NF_BPF_CT_OPTS_SZ (12)
+ */
+struct nf_conn___init *
+bpf_xdp_ct_alloc(struct xdp_md *xdp_ctx, struct bpf_sock_tuple *bpf_tuple,
+ u32 tuple__sz, struct bpf_ct_opts *opts, u32 opts__sz)
+{
+ struct xdp_buff *ctx = (struct xdp_buff *)xdp_ctx;
+ struct nf_conn *nfct;
+
+ nfct = __bpf_nf_ct_alloc_entry(dev_net(ctx->rxq->dev), bpf_tuple, tuple__sz,
+ opts, opts__sz, 10);
+ if (IS_ERR(nfct)) {
+ if (opts)
+ opts->error = PTR_ERR(nfct);
+ return NULL;
+ }
+
+ return (struct nf_conn___init *)nfct;
+}
+
/* bpf_xdp_ct_lookup - Lookup CT entry for the given tuple, and acquire a
* reference to it
*
@@ -138,25 +249,50 @@ bpf_xdp_ct_lookup(struct xdp_md *xdp_ctx, struct bpf_sock_tuple *bpf_tuple,
struct net *caller_net;
struct nf_conn *nfct;
- BUILD_BUG_ON(sizeof(struct bpf_ct_opts) != NF_BPF_CT_OPTS_SZ);
-
- if (!opts)
- return NULL;
- if (!bpf_tuple || opts->reserved[0] || opts->reserved[1] ||
- opts__sz != NF_BPF_CT_OPTS_SZ) {
- opts->error = -EINVAL;
- return NULL;
- }
caller_net = dev_net(ctx->rxq->dev);
- nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts->l4proto,
- opts->netns_id, &opts->dir);
+ nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);
if (IS_ERR(nfct)) {
- opts->error = PTR_ERR(nfct);
+ if (opts)
+ opts->error = PTR_ERR(nfct);
return NULL;
}
return nfct;
}
+/* bpf_skb_ct_alloc - Allocate a new CT entry
+ *
+ * Parameters:
+ * @skb_ctx - Pointer to ctx (__sk_buff) in TC program
+ * Cannot be NULL
+ * @bpf_tuple - Pointer to memory representing the tuple to look up
+ * Cannot be NULL
+ * @tuple__sz - Length of the tuple structure
+ * Must be one of sizeof(bpf_tuple->ipv4) or
+ * sizeof(bpf_tuple->ipv6)
+ * @opts - Additional options for allocation (documented above)
+ * Cannot be NULL
+ * @opts__sz - Length of the bpf_ct_opts structure
+ * Must be NF_BPF_CT_OPTS_SZ (12)
+ */
+struct nf_conn___init *
+bpf_skb_ct_alloc(struct __sk_buff *skb_ctx, struct bpf_sock_tuple *bpf_tuple,
+ u32 tuple__sz, struct bpf_ct_opts *opts, u32 opts__sz)
+{
+ struct sk_buff *skb = (struct sk_buff *)skb_ctx;
+ struct nf_conn *nfct;
+ struct net *net;
+
+ net = skb->dev ? dev_net(skb->dev) : sock_net(skb->sk);
+ nfct = __bpf_nf_ct_alloc_entry(net, bpf_tuple, tuple__sz, opts, opts__sz, 10);
+ if (IS_ERR(nfct)) {
+ if (opts)
+ opts->error = PTR_ERR(nfct);
+ return NULL;
+ }
+
+ return (struct nf_conn___init *)nfct;
+}
+
/* bpf_skb_ct_lookup - Lookup CT entry for the given tuple, and acquire a
* reference to it
*
@@ -181,20 +317,31 @@ bpf_skb_ct_lookup(struct __sk_buff *skb_ctx, struct bpf_sock_tuple *bpf_tuple,
struct net *caller_net;
struct nf_conn *nfct;
- BUILD_BUG_ON(sizeof(struct bpf_ct_opts) != NF_BPF_CT_OPTS_SZ);
-
- if (!opts)
- return NULL;
- if (!bpf_tuple || opts->reserved[0] || opts->reserved[1] ||
- opts__sz != NF_BPF_CT_OPTS_SZ) {
- opts->error = -EINVAL;
- return NULL;
- }
caller_net = skb->dev ? dev_net(skb->dev) : sock_net(skb->sk);
- nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts->l4proto,
- opts->netns_id, &opts->dir);
+ nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);
if (IS_ERR(nfct)) {
- opts->error = PTR_ERR(nfct);
+ if (opts)
+ opts->error = PTR_ERR(nfct);
+ return NULL;
+ }
+ return nfct;
+}
+
+/* bpf_ct_insert_entry - Add the provided entry into a CT map
+ *
+ * This must be invoked for referenced PTR_TO_BTF_ID.
+ *
+ * @nfct - Pointer to referenced nf_conn___init object, obtained
+ * using bpf_xdp_ct_alloc or bpf_skb_ct_alloc.
+ */
+struct nf_conn *bpf_ct_insert_entry(struct nf_conn___init *nfct_i)
+{
+ struct nf_conn *nfct = (struct nf_conn *)nfct_i;
+ int err;
+
+ err = nf_conntrack_hash_check_insert(nfct);
+ if (err < 0) {
+ nf_conntrack_free(nfct);
return NULL;
}
return nfct;
@@ -217,50 +364,90 @@ void bpf_ct_release(struct nf_conn *nfct)
nf_ct_put(nfct);
}
+/* bpf_ct_set_timeout - Set timeout of allocated nf_conn
+ *
+ * Sets the default timeout of newly allocated nf_conn before insertion.
+ * This helper must be invoked for refcounted pointer to nf_conn___init.
+ *
+ * Parameters:
+ * @nfct - Pointer to referenced nf_conn object, obtained using
+ * bpf_xdp_ct_alloc or bpf_skb_ct_alloc.
+ * @timeout - Timeout in msecs.
+ */
+void bpf_ct_set_timeout(struct nf_conn___init *nfct, u32 timeout)
+{
+ __nf_ct_set_timeout((struct nf_conn *)nfct, msecs_to_jiffies(timeout));
+}
+
+/* bpf_ct_change_timeout - Change timeout of inserted nf_conn
+ *
+ * Change timeout associated of the inserted or looked up nf_conn.
+ * This helper must be invoked for refcounted pointer to nf_conn.
+ *
+ * Parameters:
+ * @nfct - Pointer to referenced nf_conn object, obtained using
+ * bpf_ct_insert_entry, bpf_xdp_ct_lookup, or bpf_skb_ct_lookup.
+ * @timeout - New timeout in msecs.
+ */
+int bpf_ct_change_timeout(struct nf_conn *nfct, u32 timeout)
+{
+ return __nf_ct_change_timeout(nfct, msecs_to_jiffies(timeout));
+}
+
+/* bpf_ct_set_status - Set status field of allocated nf_conn
+ *
+ * Set the status field of the newly allocated nf_conn before insertion.
+ * This must be invoked for referenced PTR_TO_BTF_ID to nf_conn___init.
+ *
+ * Parameters:
+ * @nfct - Pointer to referenced nf_conn object, obtained using
+ * bpf_xdp_ct_alloc or bpf_skb_ct_alloc.
+ * @status - New status value.
+ */
+int bpf_ct_set_status(const struct nf_conn___init *nfct, u32 status)
+{
+ return nf_ct_change_status_common((struct nf_conn *)nfct, status);
+}
+
+/* bpf_ct_change_status - Change status of inserted nf_conn
+ *
+ * Change the status field of the provided connection tracking entry.
+ * This must be invoked for referenced PTR_TO_BTF_ID to nf_conn.
+ *
+ * Parameters:
+ * @nfct - Pointer to referenced nf_conn object, obtained using
+ * bpf_ct_insert_entry, bpf_xdp_ct_lookup or bpf_skb_ct_lookup.
+ * @status - New status value.
+ */
+int bpf_ct_change_status(struct nf_conn *nfct, u32 status)
+{
+ return nf_ct_change_status_common(nfct, status);
+}
+
__diag_pop()
-BTF_SET_START(nf_ct_xdp_check_kfunc_ids)
-BTF_ID(func, bpf_xdp_ct_lookup)
-BTF_ID(func, bpf_ct_release)
-BTF_SET_END(nf_ct_xdp_check_kfunc_ids)
-
-BTF_SET_START(nf_ct_tc_check_kfunc_ids)
-BTF_ID(func, bpf_skb_ct_lookup)
-BTF_ID(func, bpf_ct_release)
-BTF_SET_END(nf_ct_tc_check_kfunc_ids)
-
-BTF_SET_START(nf_ct_acquire_kfunc_ids)
-BTF_ID(func, bpf_xdp_ct_lookup)
-BTF_ID(func, bpf_skb_ct_lookup)
-BTF_SET_END(nf_ct_acquire_kfunc_ids)
-
-BTF_SET_START(nf_ct_release_kfunc_ids)
-BTF_ID(func, bpf_ct_release)
-BTF_SET_END(nf_ct_release_kfunc_ids)
-
-/* Both sets are identical */
-#define nf_ct_ret_null_kfunc_ids nf_ct_acquire_kfunc_ids
-
-static const struct btf_kfunc_id_set nf_conntrack_xdp_kfunc_set = {
- .owner = THIS_MODULE,
- .check_set = &nf_ct_xdp_check_kfunc_ids,
- .acquire_set = &nf_ct_acquire_kfunc_ids,
- .release_set = &nf_ct_release_kfunc_ids,
- .ret_null_set = &nf_ct_ret_null_kfunc_ids,
-};
+BTF_SET8_START(nf_ct_kfunc_set)
+BTF_ID_FLAGS(func, bpf_xdp_ct_alloc, KF_ACQUIRE | KF_RET_NULL)
+BTF_ID_FLAGS(func, bpf_xdp_ct_lookup, KF_ACQUIRE | KF_RET_NULL)
+BTF_ID_FLAGS(func, bpf_skb_ct_alloc, KF_ACQUIRE | KF_RET_NULL)
+BTF_ID_FLAGS(func, bpf_skb_ct_lookup, KF_ACQUIRE | KF_RET_NULL)
+BTF_ID_FLAGS(func, bpf_ct_insert_entry, KF_ACQUIRE | KF_RET_NULL | KF_RELEASE)
+BTF_ID_FLAGS(func, bpf_ct_release, KF_RELEASE)
+BTF_ID_FLAGS(func, bpf_ct_set_timeout, KF_TRUSTED_ARGS)
+BTF_ID_FLAGS(func, bpf_ct_change_timeout, KF_TRUSTED_ARGS)
+BTF_ID_FLAGS(func, bpf_ct_set_status, KF_TRUSTED_ARGS)
+BTF_ID_FLAGS(func, bpf_ct_change_status, KF_TRUSTED_ARGS)
+BTF_SET8_END(nf_ct_kfunc_set)
-static const struct btf_kfunc_id_set nf_conntrack_tc_kfunc_set = {
- .owner = THIS_MODULE,
- .check_set = &nf_ct_tc_check_kfunc_ids,
- .acquire_set = &nf_ct_acquire_kfunc_ids,
- .release_set = &nf_ct_release_kfunc_ids,
- .ret_null_set = &nf_ct_ret_null_kfunc_ids,
+static const struct btf_kfunc_id_set nf_conntrack_kfunc_set = {
+ .owner = THIS_MODULE,
+ .set = &nf_ct_kfunc_set,
};
int register_nf_conntrack_bpf(void)
{
int ret;
- ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &nf_conntrack_xdp_kfunc_set);
- return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &nf_conntrack_tc_kfunc_set);
+ ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &nf_conntrack_kfunc_set);
+ return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &nf_conntrack_kfunc_set);
}