[PATCH v15 net-next 21/23] net/tcp: Wire up l3index to TCP-AO

From: Dmitry Safonov
Date: Wed Oct 18 2023 - 17:00:10 EST

Similarly how TCP_MD5SIG_FLAG_IFINDEX works for TCP-MD5,
TCP_AO_KEYF_IFINDEX is an AO-key flag that binds that MKT to a specified
by L3 ifinndex. Similarly, without this flag the key will work in
the default VRF l3index = 0 for connections.
To prevent AO-keys from overlapping, it's restricted to add key B for a
socket that has key A, which have the same sndid/rcvid and one of
the following is true:
- !(A.keyflags & TCP_AO_KEYF_IFINDEX) or !(B.keyflags & TCP_AO_KEYF_IFINDEX)
so that any key is non-bound to a VRF
- A.l3index == B.l3index
both want to work for the same VRF

Additionally, it's restricted to match TCP-MD5 keys for the same peer
the following way:
|--------------|--------------------|----------------|---------------|
| | MD5 key without | MD5 key | MD5 key |
| | l3index | l3index=0 | l3index=N |
|--------------|--------------------|----------------|---------------|
| TCP-AO key | | | |
| without | reject | reject | reject |
| l3index | | | |
|--------------|--------------------|----------------|---------------|
| TCP-AO key | | | |
| l3index=0 | reject | reject | allow |
|--------------|--------------------|----------------|---------------|
| TCP-AO key | | | |
| l3index=N | reject | allow | reject |
|--------------|--------------------|----------------|---------------|

This is done with the help of tcp_md5_do_lookup_any_l3index() to reject
adding AO key without TCP_AO_KEYF_IFINDEX if there's TCP-MD5 in any VRF.
This is important for case where sysctl_tcp_l3mdev_accept = 1
Similarly, for TCP-AO lookups tcp_ao_do_lookup() may be used with
l3index < 0, so that __tcp_ao_key_cmp() will match TCP-AO key in any VRF.

Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx>
Acked-by: David Ahern <dsahern@xxxxxxxxxx>
---
include/net/tcp.h | 11 +--
include/net/tcp_ao.h | 18 ++---
net/ipv4/syncookies.c | 6 +-
net/ipv4/tcp_ao.c | 170 +++++++++++++++++++++++++++++++-----------
net/ipv4/tcp_ipv4.c | 10 ++-
net/ipv6/syncookies.c | 5 +-
net/ipv6/tcp_ao.c | 21 +++---
net/ipv6/tcp_ipv6.c | 15 +++-
8 files changed, 177 insertions(+), 79 deletions(-)

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 942628c3566a..73dd61723368 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2685,7 +2685,7 @@ static inline int tcp_parse_auth_options(const struct tcphdr *th,
}

static inline bool tcp_ao_required(struct sock *sk, const void *saddr,
- int family, bool stat_inc)
+ int family, int l3index, bool stat_inc)
{
#ifdef CONFIG_TCP_AO
struct tcp_ao_info *ao_info;
@@ -2699,7 +2699,7 @@ static inline bool tcp_ao_required(struct sock *sk, const void *saddr,
if (!ao_info)
return false;

- ao_key = tcp_ao_do_lookup(sk, saddr, family, -1, -1);
+ ao_key = tcp_ao_do_lookup(sk, l3index, saddr, family, -1, -1);
if (ao_info->ao_required || ao_key) {
if (stat_inc) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOREQUIRED);
@@ -2752,21 +2752,22 @@ tcp_inbound_hash(struct sock *sk, const struct request_sock *req,
* the last key is impossible to remove, so there's
* always at least one current_key.
*/
- if (tcp_ao_required(sk, saddr, family, true)) {
+ if (tcp_ao_required(sk, saddr, family, l3index, true)) {
tcp_hash_fail("AO hash is required, but not found",
family, skb, "L3 index %d", l3index);
return SKB_DROP_REASON_TCP_AONOTFOUND;
}
if (unlikely(tcp_md5_do_lookup(sk, l3index, saddr, family))) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
- tcp_hash_fail("MD5 Hash not found", family, skb, "");
+ tcp_hash_fail("MD5 Hash not found",
+ family, skb, "L3 index %d", l3index);
return SKB_DROP_REASON_TCP_MD5NOTFOUND;
}
return SKB_NOT_DROPPED_YET;
}

if (aoh)
- return tcp_inbound_ao_hash(sk, skb, family, req, aoh);
+ return tcp_inbound_ao_hash(sk, skb, family, req, l3index, aoh);

return tcp_inbound_md5_hash(sk, skb, saddr, daddr, family,
l3index, md5_location);
diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h
index a38408072ea8..edd6748b2cfa 100644
--- a/include/net/tcp_ao.h
+++ b/include/net/tcp_ao.h
@@ -33,6 +33,7 @@ struct tcp_ao_key {
u8 key[TCP_AO_MAXKEYLEN] __tcp_ao_key_align;
unsigned int tcp_sigpool_id;
unsigned int digest_size;
+ int l3index;
u8 prefixlen;
u8 family;
u8 keylen;
@@ -200,10 +201,10 @@ int tcp_ao_get_mkts(struct sock *sk, sockptr_t optval, sockptr_t optlen);
int tcp_ao_get_sock_info(struct sock *sk, sockptr_t optval, sockptr_t optlen);
enum skb_drop_reason tcp_inbound_ao_hash(struct sock *sk,
const struct sk_buff *skb, unsigned short int family,
- const struct request_sock *req,
+ const struct request_sock *req, int l3index,
const struct tcp_ao_hdr *aoh);
u32 tcp_ao_compute_sne(u32 next_sne, u32 next_seq, u32 seq);
-struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk,
+struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk, int l3index,
const union tcp_ao_addr *addr,
int family, int sndid, int rcvid);
int tcp_ao_hash_hdr(unsigned short family, char *ao_hash,
@@ -245,9 +246,6 @@ int tcp_v6_ao_calc_key_sk(struct tcp_ao_key *mkt, u8 *key,
__be32 disn, bool send);
int tcp_v6_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key,
struct request_sock *req);
-struct tcp_ao_key *tcp_v6_ao_do_lookup(const struct sock *sk,
- const struct in6_addr *addr,
- int sndid, int rcvid);
struct tcp_ao_key *tcp_v6_ao_lookup(const struct sock *sk,
struct sock *addr_sk, int sndid, int rcvid);
struct tcp_ao_key *tcp_v6_ao_lookup_rsk(const struct sock *sk,
@@ -265,7 +263,7 @@ void tcp_ao_finish_connect(struct sock *sk, struct sk_buff *skb);
void tcp_ao_connect_init(struct sock *sk);
void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb,
struct tcp_request_sock *treq,
- unsigned short int family);
+ unsigned short int family, int l3index);
#else /* CONFIG_TCP_AO */

static inline int tcp_ao_transmit_skb(struct sock *sk, struct sk_buff *skb,
@@ -277,7 +275,7 @@ static inline int tcp_ao_transmit_skb(struct sock *sk, struct sk_buff *skb,

static inline void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb,
struct tcp_request_sock *treq,
- unsigned short int family)
+ unsigned short int family, int l3index)
{
}

@@ -289,13 +287,15 @@ static inline bool tcp_ao_ignore_icmp(const struct sock *sk, int family,

static inline enum skb_drop_reason tcp_inbound_ao_hash(struct sock *sk,
const struct sk_buff *skb, unsigned short int family,
- const struct request_sock *req, const struct tcp_ao_hdr *aoh)
+ const struct request_sock *req, int l3index,
+ const struct tcp_ao_hdr *aoh)
{
return SKB_NOT_DROPPED_YET;
}

static inline struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk,
- const union tcp_ao_addr *addr, int family, int sndid, int rcvid)
+ int l3index, const union tcp_ao_addr *addr,
+ int family, int sndid, int rcvid)
{
return NULL;
}
diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index 23fca22bc992..40b7f4c659f8 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -338,6 +338,7 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
__u8 rcv_wscale;
struct flowi4 fl4;
u32 tsoff = 0;
+ int l3index;

if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies) ||
!th->ack || th->rst)
@@ -394,13 +395,14 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb)
treq->snt_synack = 0;
treq->tfo_listener = false;

- tcp_ao_syncookie(sk, skb, treq, AF_INET);
-
if (IS_ENABLED(CONFIG_SMC))
ireq->smc_ok = 0;

ireq->ir_iif = inet_request_bound_dev_if(sk, skb);

+ l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif);
+ tcp_ao_syncookie(sk, skb, treq, AF_INET, l3index);
+
/* We throwed the options of the initial SYN away, so we hope
* the ACK carries the same options again (see RFC1122 4.2.3.8)
*/
diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c
index ffce8ca60ff2..b5ac3e73e1da 100644
--- a/net/ipv4/tcp_ao.c
+++ b/net/ipv4/tcp_ao.c
@@ -136,7 +136,7 @@ static int ipv4_prefix_cmp(const struct in_addr *addr1,
return memcmp(&a1, &a2, sizeof(a1));
}

-static int __tcp_ao_key_cmp(const struct tcp_ao_key *key,
+static int __tcp_ao_key_cmp(const struct tcp_ao_key *key, int l3index,
const union tcp_ao_addr *addr, u8 prefixlen,
int family, int sndid, int rcvid)
{
@@ -144,6 +144,10 @@ static int __tcp_ao_key_cmp(const struct tcp_ao_key *key,
return (key->sndid > sndid) ? 1 : -1;
if (rcvid >= 0 && key->rcvid != rcvid)
return (key->rcvid > rcvid) ? 1 : -1;
+ if (l3index >= 0 && (key->keyflags & TCP_AO_KEYF_IFINDEX)) {
+ if (key->l3index != l3index)
+ return (key->l3index > l3index) ? 1 : -1;
+ }

if (family == AF_UNSPEC)
return 0;
@@ -168,7 +172,7 @@ static int __tcp_ao_key_cmp(const struct tcp_ao_key *key,
return -1;
}

-static int tcp_ao_key_cmp(const struct tcp_ao_key *key,
+static int tcp_ao_key_cmp(const struct tcp_ao_key *key, int l3index,
const union tcp_ao_addr *addr, u8 prefixlen,
int family, int sndid, int rcvid)
{
@@ -176,14 +180,16 @@ static int tcp_ao_key_cmp(const struct tcp_ao_key *key,
if (family == AF_INET6 && ipv6_addr_v4mapped(&addr->a6)) {
__be32 addr4 = addr->a6.s6_addr32[3];

- return __tcp_ao_key_cmp(key, (union tcp_ao_addr *)&addr4,
+ return __tcp_ao_key_cmp(key, l3index,
+ (union tcp_ao_addr *)&addr4,
prefixlen, AF_INET, sndid, rcvid);
}
#endif
- return __tcp_ao_key_cmp(key, addr, prefixlen, family, sndid, rcvid);
+ return __tcp_ao_key_cmp(key, l3index, addr,
+ prefixlen, family, sndid, rcvid);
}

-static struct tcp_ao_key *__tcp_ao_do_lookup(const struct sock *sk,
+static struct tcp_ao_key *__tcp_ao_do_lookup(const struct sock *sk, int l3index,
const union tcp_ao_addr *addr, int family, u8 prefix,
int sndid, int rcvid)
{
@@ -201,17 +207,18 @@ static struct tcp_ao_key *__tcp_ao_do_lookup(const struct sock *sk,
hlist_for_each_entry_rcu(key, &ao->head, node) {
u8 prefixlen = min(prefix, key->prefixlen);

- if (!tcp_ao_key_cmp(key, addr, prefixlen, family, sndid, rcvid))
+ if (!tcp_ao_key_cmp(key, l3index, addr, prefixlen,
+ family, sndid, rcvid))
return key;
}
return NULL;
}

-struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk,
+struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk, int l3index,
const union tcp_ao_addr *addr,
int family, int sndid, int rcvid)
{
- return __tcp_ao_do_lookup(sk, addr, family, U8_MAX, sndid, rcvid);
+ return __tcp_ao_do_lookup(sk, l3index, addr, family, U8_MAX, sndid, rcvid);
}

static struct tcp_ao_info *tcp_ao_alloc_info(gfp_t flags)
@@ -677,18 +684,22 @@ struct tcp_ao_key *tcp_v4_ao_lookup_rsk(const struct sock *sk,
struct request_sock *req,
int sndid, int rcvid)
{
- union tcp_ao_addr *addr =
- (union tcp_ao_addr *)&inet_rsk(req)->ir_rmt_addr;
+ struct inet_request_sock *ireq = inet_rsk(req);
+ union tcp_ao_addr *addr = (union tcp_ao_addr *)&ireq->ir_rmt_addr;
+ int l3index;

- return tcp_ao_do_lookup(sk, addr, AF_INET, sndid, rcvid);
+ l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif);
+ return tcp_ao_do_lookup(sk, l3index, addr, AF_INET, sndid, rcvid);
}

struct tcp_ao_key *tcp_v4_ao_lookup(const struct sock *sk, struct sock *addr_sk,
int sndid, int rcvid)
{
+ int l3index = l3mdev_master_ifindex_by_index(sock_net(sk),
+ addr_sk->sk_bound_dev_if);
union tcp_ao_addr *addr = (union tcp_ao_addr *)&addr_sk->sk_daddr;

- return tcp_ao_do_lookup(sk, addr, AF_INET, sndid, rcvid);
+ return tcp_ao_do_lookup(sk, l3index, addr, AF_INET, sndid, rcvid);
}

int tcp_ao_prepare_reset(const struct sock *sk, struct sk_buff *skb,
@@ -738,7 +749,8 @@ int tcp_ao_prepare_reset(const struct sock *sk, struct sk_buff *skb,
ao_info = rcu_dereference(tcp_sk(sk)->ao_info);
if (!ao_info)
return -ENOENT;
- *key = tcp_ao_do_lookup(sk, addr, family, -1, aoh->rnext_keyid);
+ *key = tcp_ao_do_lookup(sk, l3index, addr, family,
+ -1, aoh->rnext_keyid);
if (!*key)
return -ENOENT;
*traffic_key = kmalloc(tcp_ao_digest_size(*key), GFP_ATOMIC);
@@ -814,24 +826,26 @@ int tcp_ao_transmit_skb(struct sock *sk, struct sk_buff *skb,

static struct tcp_ao_key *tcp_ao_inbound_lookup(unsigned short int family,
const struct sock *sk, const struct sk_buff *skb,
- int sndid, int rcvid)
+ int sndid, int rcvid, int l3index)
{
if (family == AF_INET) {
const struct iphdr *iph = ip_hdr(skb);

- return tcp_ao_do_lookup(sk, (union tcp_ao_addr *)&iph->saddr,
- AF_INET, sndid, rcvid);
+ return tcp_ao_do_lookup(sk, l3index,
+ (union tcp_ao_addr *)&iph->saddr,
+ AF_INET, sndid, rcvid);
} else {
const struct ipv6hdr *iph = ipv6_hdr(skb);

- return tcp_ao_do_lookup(sk, (union tcp_ao_addr *)&iph->saddr,
- AF_INET6, sndid, rcvid);
+ return tcp_ao_do_lookup(sk, l3index,
+ (union tcp_ao_addr *)&iph->saddr,
+ AF_INET6, sndid, rcvid);
}
}

void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb,
struct tcp_request_sock *treq,
- unsigned short int family)
+ unsigned short int family, int l3index)
{
const struct tcphdr *th = tcp_hdr(skb);
const struct tcp_ao_hdr *aoh;
@@ -842,7 +856,7 @@ void tcp_ao_syncookie(struct sock *sk, const struct sk_buff *skb,
if (tcp_parse_auth_options(th, NULL, &aoh) || !aoh)
return;

- key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid);
+ key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid, l3index);
if (!key)
/* Key not found, continue without TCP-AO */
return;
@@ -856,7 +870,7 @@ static enum skb_drop_reason
tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb,
unsigned short int family, struct tcp_ao_info *info,
const struct tcp_ao_hdr *aoh, struct tcp_ao_key *key,
- u8 *traffic_key, u8 *phash, u32 sne)
+ u8 *traffic_key, u8 *phash, u32 sne, int l3index)
{
u8 maclen = aoh->length - sizeof(struct tcp_ao_hdr);
const struct tcphdr *th = tcp_hdr(skb);
@@ -867,7 +881,8 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb,
atomic64_inc(&info->counters.pkt_bad);
atomic64_inc(&key->pkt_bad);
tcp_hash_fail("AO hash wrong length", family, skb,
- "%u != %d", maclen, tcp_ao_maclen(key));
+ "%u != %d L3index: %d", maclen,
+ tcp_ao_maclen(key), l3index);
return SKB_DROP_REASON_TCP_AOFAILURE;
}

@@ -882,7 +897,8 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb,
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOBAD);
atomic64_inc(&info->counters.pkt_bad);
atomic64_inc(&key->pkt_bad);
- tcp_hash_fail("AO hash mismatch", family, skb, "");
+ tcp_hash_fail("AO hash mismatch", family, skb,
+ "L3index: %d", l3index);
kfree(hash_buf);
return SKB_DROP_REASON_TCP_AOFAILURE;
}
@@ -896,7 +912,7 @@ tcp_ao_verify_hash(const struct sock *sk, const struct sk_buff *skb,
enum skb_drop_reason
tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
unsigned short int family, const struct request_sock *req,
- const struct tcp_ao_hdr *aoh)
+ int l3index, const struct tcp_ao_hdr *aoh)
{
const struct tcphdr *th = tcp_hdr(skb);
u8 *phash = (u8 *)(aoh + 1); /* hash goes just after the header */
@@ -911,7 +927,7 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
if (!info) {
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND);
tcp_hash_fail("AO key not found", family, skb,
- "keyid: %u", aoh->keyid);
+ "keyid: %u L3index: %d", aoh->keyid, l3index);
return SKB_DROP_REASON_TCP_AOUNEXPECTED;
}

@@ -945,7 +961,7 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
/* Established socket, traffic key are cached */
traffic_key = rcv_other_key(key);
err = tcp_ao_verify_hash(sk, skb, family, info, aoh, key,
- traffic_key, phash, sne);
+ traffic_key, phash, sne, l3index);
if (err)
return err;
current_key = READ_ONCE(info->current_key);
@@ -966,7 +982,7 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
* - request sockets would race on those key pointers
* - tcp_ao_del_cmd() allows async key removal
*/
- key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid);
+ key = tcp_ao_inbound_lookup(family, sk, skb, -1, aoh->keyid, l3index);
if (!key)
goto key_not_found;

@@ -1006,7 +1022,7 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
return SKB_DROP_REASON_NOT_SPECIFIED;
tcp_ao_calc_key_skb(key, traffic_key, skb, sisn, disn, family);
ret = tcp_ao_verify_hash(sk, skb, family, info, aoh, key,
- traffic_key, phash, sne);
+ traffic_key, phash, sne, l3index);
kfree(traffic_key);
return ret;

@@ -1014,7 +1030,7 @@ tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb,
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAOKEYNOTFOUND);
atomic64_inc(&info->counters.key_not_found);
tcp_hash_fail("Requested by the peer AO key id not found",
- family, skb, "");
+ family, skb, "L3index: %d", l3index);
return SKB_DROP_REASON_TCP_AOKEYNOTFOUND;
}

@@ -1042,7 +1058,7 @@ void tcp_ao_connect_init(struct sock *sk)
struct tcp_ao_info *ao_info;
union tcp_ao_addr *addr;
struct tcp_ao_key *key;
- int family;
+ int family, l3index;

ao_info = rcu_dereference_protected(tp->ao_info,
lockdep_sock_is_held(sk));
@@ -1059,9 +1075,11 @@ void tcp_ao_connect_init(struct sock *sk)
#endif
else
return;
+ l3index = l3mdev_master_ifindex_by_index(sock_net(sk),
+ sk->sk_bound_dev_if);

hlist_for_each_entry_rcu(key, &ao_info->head, node) {
- if (!tcp_ao_key_cmp(key, addr, key->prefixlen, family, -1, -1))
+ if (!tcp_ao_key_cmp(key, l3index, addr, key->prefixlen, family, -1, -1))
continue;

if (key == ao_info->current_key)
@@ -1134,9 +1152,9 @@ int tcp_ao_copy_all_matching(const struct sock *sk, struct sock *newsk,
struct tcp_ao_key *key, *new_key, *first_key;
struct tcp_ao_info *new_ao, *ao;
struct hlist_node *key_head;
+ int l3index, ret = -ENOMEM;
union tcp_ao_addr *addr;
bool match = false;
- int ret = -ENOMEM;

ao = rcu_dereference(tcp_sk(sk)->ao_info);
if (!ao)
@@ -1164,9 +1182,11 @@ int tcp_ao_copy_all_matching(const struct sock *sk, struct sock *newsk,
ret = -EAFNOSUPPORT;
goto free_ao;
}
+ l3index = l3mdev_master_ifindex_by_index(sock_net(newsk),
+ newsk->sk_bound_dev_if);

hlist_for_each_entry_rcu(key, &ao->head, node) {
- if (tcp_ao_key_cmp(key, addr, key->prefixlen, family, -1, -1))
+ if (tcp_ao_key_cmp(key, l3index, addr, key->prefixlen, family, -1, -1))
continue;

new_key = tcp_ao_copy_key(newsk, key);
@@ -1470,7 +1490,8 @@ static struct tcp_ao_info *setsockopt_ao_info(struct sock *sk)
return ERR_PTR(-ESOCKTNOSUPPORT);
}

-#define TCP_AO_KEYF_ALL (TCP_AO_KEYF_EXCLUDE_OPT)
+#define TCP_AO_KEYF_ALL (TCP_AO_KEYF_IFINDEX | TCP_AO_KEYF_EXCLUDE_OPT)
+#define TCP_AO_GET_KEYF_VALID (TCP_AO_KEYF_IFINDEX)

static struct tcp_ao_key *tcp_ao_key_alloc(struct sock *sk,
struct tcp_ao_add *cmd)
@@ -1534,8 +1555,8 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
union tcp_ao_addr *addr;
struct tcp_ao_key *key;
struct tcp_ao_add cmd;
+ int ret, l3index = 0;
bool first = false;
- int ret;

if (optlen < sizeof(cmd))
return -EINVAL;
@@ -1565,9 +1586,46 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
return -EINVAL;
}

+ if (cmd.ifindex && !(cmd.keyflags & TCP_AO_KEYF_IFINDEX))
+ return -EINVAL;
+
+ /* For cmd.tcp_ifindex = 0 the key will apply to the default VRF */
+ if (cmd.keyflags & TCP_AO_KEYF_IFINDEX && cmd.ifindex) {
+ int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
+ struct net_device *dev;
+
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(sock_net(sk), cmd.ifindex);
+ if (dev && netif_is_l3_master(dev))
+ l3index = dev->ifindex;
+ rcu_read_unlock();
+
+ if (!dev || !l3index)
+ return -EINVAL;
+
+ /* It's still possible to bind after adding keys or even
+ * re-bind to a different dev (with CAP_NET_RAW).
+ * So, no reason to return error here, rather try to be
+ * nice and warn the user.
+ */
+ if (bound_dev_if && bound_dev_if != cmd.ifindex)
+ net_warn_ratelimited("AO key ifindex %d != sk bound ifindex %d\n",
+ cmd.ifindex, bound_dev_if);
+ }
+
/* Don't allow keys for peers that have a matching TCP-MD5 key */
- if (tcp_md5_do_lookup_any_l3index(sk, addr, family))
- return -EKEYREJECTED;
+ if (cmd.keyflags & TCP_AO_KEYF_IFINDEX) {
+ /* Non-_exact version of tcp_md5_do_lookup() will
+ * as well match keys that aren't bound to a specific VRF
+ * (that will make them match AO key with
+ * sysctl_tcp_l3dev_accept = 1
+ */
+ if (tcp_md5_do_lookup(sk, l3index, addr, family))
+ return -EKEYREJECTED;
+ } else {
+ if (tcp_md5_do_lookup_any_l3index(sk, addr, family))
+ return -EKEYREJECTED;
+ }

ao_info = setsockopt_ao_info(sk);
if (IS_ERR(ao_info))
@@ -1584,10 +1642,9 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
* > The IDs of MKTs MUST NOT overlap where their
* > TCP connection identifiers overlap.
*/
- if (__tcp_ao_do_lookup(sk, addr, family,
- cmd.prefix, -1, cmd.rcvid))
+ if (__tcp_ao_do_lookup(sk, l3index, addr, family, cmd.prefix, -1, cmd.rcvid))
return -EEXIST;
- if (__tcp_ao_do_lookup(sk, addr, family,
+ if (__tcp_ao_do_lookup(sk, l3index, addr, family,
cmd.prefix, cmd.sndid, -1))
return -EEXIST;
}
@@ -1606,6 +1663,7 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
key->keyflags = cmd.keyflags;
key->sndid = cmd.sndid;
key->rcvid = cmd.rcvid;
+ key->l3index = l3index;
atomic64_set(&key->pkt_good, 0);
atomic64_set(&key->pkt_bad, 0);

@@ -1694,17 +1752,17 @@ static int tcp_ao_delete_key(struct sock *sk, struct tcp_ao_info *ao_info,
return err;
}

+#define TCP_AO_DEL_KEYF_ALL (TCP_AO_KEYF_IFINDEX)
static int tcp_ao_del_cmd(struct sock *sk, unsigned short int family,
sockptr_t optval, int optlen)
{
struct tcp_ao_key *key, *new_current = NULL, *new_rnext = NULL;
+ int err, addr_len, l3index = 0;
struct tcp_ao_info *ao_info;
union tcp_ao_addr *addr;
struct tcp_ao_del cmd;
- int addr_len;
__u8 prefix;
u16 port;
- int err;

if (optlen < sizeof(cmd))
return -EINVAL;
@@ -1721,6 +1779,17 @@ static int tcp_ao_del_cmd(struct sock *sk, unsigned short int family,
return -EINVAL;
}

+ if (cmd.keyflags & ~TCP_AO_DEL_KEYF_ALL)
+ return -EINVAL;
+
+ /* No sanity check for TCP_AO_KEYF_IFINDEX as if a VRF
+ * was destroyed, there still should be a way to delete keys,
+ * that were bound to that l3intf. So, fail late at lookup stage
+ * if there is no key for that ifindex.
+ */
+ if (cmd.ifindex && !(cmd.keyflags & TCP_AO_KEYF_IFINDEX))
+ return -EINVAL;
+
ao_info = setsockopt_ao_info(sk);
if (IS_ERR(ao_info))
return PTR_ERR(ao_info);
@@ -1788,6 +1857,13 @@ static int tcp_ao_del_cmd(struct sock *sk, unsigned short int family,
memcmp(addr, &key->addr, addr_len))
continue;

+ if ((cmd.keyflags & TCP_AO_KEYF_IFINDEX) !=
+ (key->keyflags & TCP_AO_KEYF_IFINDEX))
+ continue;
+
+ if (key->l3index != l3index)
+ continue;
+
if (key == new_current || key == new_rnext)
continue;

@@ -1973,10 +2049,10 @@ static int tcp_ao_copy_mkts_to_user(struct tcp_ao_info *ao_info,
struct tcp_ao_key *key, *current_key;
bool do_address_matching = true;
union tcp_ao_addr *addr = NULL;
+ int err, l3index, user_len;
unsigned int max_keys; /* maximum number of keys to copy to user */
size_t out_offset = 0;
size_t bytes_to_write; /* number of bytes to write to user level */
- int err, user_len;
u32 matched_keys; /* keys from ao_info matched so far */
int optlen_out;
__be16 port = 0;
@@ -1995,11 +2071,16 @@ static int tcp_ao_copy_mkts_to_user(struct tcp_ao_info *ao_info,

if (opt_in.pkt_good || opt_in.pkt_bad)
return -EINVAL;
+ if (opt_in.keyflags & ~TCP_AO_GET_KEYF_VALID)
+ return -EINVAL;
+ if (opt_in.ifindex && !(opt_in.keyflags & TCP_AO_KEYF_IFINDEX))
+ return -EINVAL;

if (opt_in.reserved != 0)
return -EINVAL;

max_keys = opt_in.nkeys;
+ l3index = (opt_in.keyflags & TCP_AO_KEYF_IFINDEX) ? opt_in.ifindex : -1;

if (opt_in.get_all || opt_in.is_current || opt_in.is_rnext) {
if (opt_in.get_all && (opt_in.is_current || opt_in.is_rnext))
@@ -2101,7 +2182,7 @@ static int tcp_ao_copy_mkts_to_user(struct tcp_ao_info *ao_info,
continue;
}

- if (tcp_ao_key_cmp(key, addr, opt_in.prefix,
+ if (tcp_ao_key_cmp(key, l3index, addr, opt_in.prefix,
opt_in.addr.ss_family,
opt_in.sndid, opt_in.rcvid) != 0)
continue;
@@ -2134,6 +2215,7 @@ static int tcp_ao_copy_mkts_to_user(struct tcp_ao_info *ao_info,
opt_out.nkeys = 0;
opt_out.maclen = key->maclen;
opt_out.keylen = key->keylen;
+ opt_out.ifindex = key->l3index;
opt_out.pkt_good = atomic64_read(&key->pkt_good);
opt_out.pkt_bad = atomic64_read(&key->pkt_bad);
memcpy(&opt_out.key, key->key, key->keylen);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 4bef91cd3996..a9dd5dc0f6ac 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1086,6 +1086,7 @@ static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
tcp_rsk_used_ao(req)) {
const union tcp_md5_addr *addr;
const struct tcp_ao_hdr *aoh;
+ int l3index;

/* Invalid TCP option size or twice included auth */
if (tcp_parse_auth_options(tcp_hdr(skb), NULL, &aoh))
@@ -1094,11 +1095,12 @@ static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
return;

addr = (union tcp_md5_addr *)&ip_hdr(skb)->saddr;
- key.ao_key = tcp_ao_do_lookup(sk, addr, AF_INET,
+ l3index = tcp_v4_sdif(skb) ? inet_iif(skb) : 0;
+ key.ao_key = tcp_ao_do_lookup(sk, l3index, addr, AF_INET,
aoh->rnext_keyid, -1);
if (unlikely(!key.ao_key)) {
/* Send ACK with any matching MKT for the peer */
- key.ao_key = tcp_ao_do_lookup(sk, addr, AF_INET, -1, -1);
+ key.ao_key = tcp_ao_do_lookup(sk, l3index, addr, AF_INET, -1, -1);
/* Matching key disappeared (user removed the key?)
* let the handshake timeout.
*/
@@ -1492,6 +1494,7 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, int optname,
const union tcp_md5_addr *addr;
u8 prefixlen = 32;
int l3index = 0;
+ bool l3flag;
u8 flags;

if (optlen < sizeof(cmd))
@@ -1504,6 +1507,7 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, int optname,
return -EINVAL;

flags = cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX;
+ l3flag = cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX;

if (optname == TCP_MD5SIG_EXT &&
cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) {
@@ -1541,7 +1545,7 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, int optname,
/* Don't allow keys for peers that have a matching TCP-AO key.
* See the comment in tcp_ao_add_cmd()
*/
- if (tcp_ao_required(sk, addr, AF_INET, false))
+ if (tcp_ao_required(sk, addr, AF_INET, l3flag ? l3index : -1, false))
return -EKEYREJECTED;

return tcp_md5_do_add(sk, addr, AF_INET, prefixlen, l3index, flags,
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index ad7a8caa7b2a..500f6ed3b8cf 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -140,6 +140,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
struct dst_entry *dst;
__u8 rcv_wscale;
u32 tsoff = 0;
+ int l3index;

if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies) ||
!th->ack || th->rst)
@@ -214,7 +215,9 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
treq->snt_isn = cookie;
treq->ts_off = 0;
treq->txhash = net_tx_rndhash();
- tcp_ao_syncookie(sk, skb, treq, AF_INET6);
+
+ l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif);
+ tcp_ao_syncookie(sk, skb, treq, AF_INET6, l3index);

if (IS_ENABLED(CONFIG_SMC))
ireq->smc_ok = 0;
diff --git a/net/ipv6/tcp_ao.c b/net/ipv6/tcp_ao.c
index 8b04611c9078..3c09ac26206e 100644
--- a/net/ipv6/tcp_ao.c
+++ b/net/ipv6/tcp_ao.c
@@ -87,30 +87,29 @@ int tcp_v6_ao_calc_key_rsk(struct tcp_ao_key *mkt, u8 *key,
htonl(tcp_rsk(req)->rcv_isn));
}

-struct tcp_ao_key *tcp_v6_ao_do_lookup(const struct sock *sk,
- const struct in6_addr *addr,
- int sndid, int rcvid)
-{
- return tcp_ao_do_lookup(sk, (union tcp_ao_addr *)addr, AF_INET6,
- sndid, rcvid);
-}
-
struct tcp_ao_key *tcp_v6_ao_lookup(const struct sock *sk,
struct sock *addr_sk,
int sndid, int rcvid)
{
+ int l3index = l3mdev_master_ifindex_by_index(sock_net(sk),
+ addr_sk->sk_bound_dev_if);
struct in6_addr *addr = &addr_sk->sk_v6_daddr;

- return tcp_v6_ao_do_lookup(sk, addr, sndid, rcvid);
+ return tcp_ao_do_lookup(sk, l3index, (union tcp_ao_addr *)addr,
+ AF_INET6, sndid, rcvid);
}

struct tcp_ao_key *tcp_v6_ao_lookup_rsk(const struct sock *sk,
struct request_sock *req,
int sndid, int rcvid)
{
- struct in6_addr *addr = &inet_rsk(req)->ir_v6_rmt_addr;
+ struct inet_request_sock *ireq = inet_rsk(req);
+ struct in6_addr *addr = &ireq->ir_v6_rmt_addr;
+ int l3index;

- return tcp_v6_ao_do_lookup(sk, addr, sndid, rcvid);
+ l3index = l3mdev_master_ifindex_by_index(sock_net(sk), ireq->ir_iif);
+ return tcp_ao_do_lookup(sk, l3index, (union tcp_ao_addr *)addr,
+ AF_INET6, sndid, rcvid);
}

int tcp_v6_ao_hash_pseudoheader(struct tcp_sigpool *hp,
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 4c9723dc1e66..dfa6a1a2c6e2 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -609,6 +609,7 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
union tcp_ao_addr *addr;
int l3index = 0;
u8 prefixlen;
+ bool l3flag;
u8 flags;

if (optlen < sizeof(cmd))
@@ -621,6 +622,7 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
return -EINVAL;

flags = cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX;
+ l3flag = cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX;

if (optname == TCP_MD5SIG_EXT &&
cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) {
@@ -667,7 +669,8 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
/* Don't allow keys for peers that have a matching TCP-AO key.
* See the comment in tcp_ao_add_cmd()
*/
- if (tcp_ao_required(sk, addr, AF_INET, false))
+ if (tcp_ao_required(sk, addr, AF_INET,
+ l3flag ? l3index : -1, false))
return -EKEYREJECTED;
return tcp_md5_do_add(sk, addr,
AF_INET, prefixlen, l3index, flags,
@@ -679,7 +682,7 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname,
/* Don't allow keys for peers that have a matching TCP-AO key.
* See the comment in tcp_ao_add_cmd()
*/
- if (tcp_ao_required(sk, addr, AF_INET6, false))
+ if (tcp_ao_required(sk, addr, AF_INET6, l3flag ? l3index : -1, false))
return -EKEYREJECTED;

return tcp_md5_do_add(sk, addr, AF_INET6, prefixlen, l3index, flags,
@@ -1219,10 +1222,14 @@ static void tcp_v6_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
return;
if (!aoh)
return;
- key.ao_key = tcp_v6_ao_do_lookup(sk, addr, aoh->rnext_keyid, -1);
+ key.ao_key = tcp_ao_do_lookup(sk, l3index,
+ (union tcp_ao_addr *)addr,
+ AF_INET6, aoh->rnext_keyid, -1);
if (unlikely(!key.ao_key)) {
/* Send ACK with any matching MKT for the peer */
- key.ao_key = tcp_v6_ao_do_lookup(sk, addr, -1, -1);
+ key.ao_key = tcp_ao_do_lookup(sk, l3index,
+ (union tcp_ao_addr *)addr,
+ AF_INET6, -1, -1);
/* Matching key disappeared (user removed the key?)
* let the handshake timeout.
*/
--
2.42.0