From: Davide Caratti <dcaratti@xxxxxxxxxx>
[ Upstream commit 13832ae2755395b2585500c85b64f5109a44227e ]
Currently, Linux computes the HMAC contained in ADD_ADDR sub-option using
the Address Id and the IP Address, and hardcodes a destination port equal
to zero. This is not ok for ADD_ADDR with port: ensure to account for the
endpoint port when computing the HMAC, in compliance with RFC8684 §3.4.1.
Fixes: 22fb85ffaefb ("mptcp: add port support for ADD_ADDR suboption writing")
Reviewed-by: Mat Martineau <mathew.j.martineau@xxxxxxxxxxxxxxx>
Acked-by: Geliang Tang <geliangtang@xxxxxxxxx>
Signed-off-by: Davide Caratti <dcaratti@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/mptcp/options.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 2e26e39169b8..37ef0bf098f6 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -555,15 +555,15 @@ static bool mptcp_established_options_dss(struct sock *sk, struct sk_buff *skb,
}
static u64 add_addr_generate_hmac(u64 key1, u64 key2, u8 addr_id,
- struct in_addr *addr)
+ struct in_addr *addr, u16 port)
{
u8 hmac[SHA256_DIGEST_SIZE];
u8 msg[7];
msg[0] = addr_id;
memcpy(&msg[1], &addr->s_addr, 4);
- msg[5] = 0;
- msg[6] = 0;
+ msg[5] = port >> 8;
+ msg[6] = port & 0xFF;
mptcp_crypto_hmac_sha(key1, key2, msg, 7, hmac);
@@ -572,15 +572,15 @@ static u64 add_addr_generate_hmac(u64 key1, u64 key2, u8 addr_id,
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
static u64 add_addr6_generate_hmac(u64 key1, u64 key2, u8 addr_id,
- struct in6_addr *addr)
+ struct in6_addr *addr, u16 port)
{
u8 hmac[SHA256_DIGEST_SIZE];
u8 msg[19];
msg[0] = addr_id;
memcpy(&msg[1], &addr->s6_addr, 16);
- msg[17] = 0;
- msg[18] = 0;
+ msg[17] = port >> 8;
+ msg[18] = port & 0xFF;
mptcp_crypto_hmac_sha(key1, key2, msg, 19, hmac);
@@ -634,7 +634,8 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
opts->ahmac = add_addr_generate_hmac(msk->local_key,
msk->remote_key,
opts->addr_id,
- &opts->addr);
+ &opts->addr,
+ opts->port);
}
}
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
@@ -645,7 +646,8 @@ static bool mptcp_established_options_add_addr(struct sock *sk, struct sk_buff *
opts->ahmac = add_addr6_generate_hmac(msk->local_key,
msk->remote_key,
opts->addr_id,
- &opts->addr6);
+ &opts->addr6,
+ opts->port);
}
}
#endif
@@ -922,12 +924,14 @@ static bool add_addr_hmac_valid(struct mptcp_sock *msk,
if (mp_opt->family == MPTCP_ADDR_IPVERSION_4)
hmac = add_addr_generate_hmac(msk->remote_key,
msk->local_key,
- mp_opt->addr_id, &mp_opt->addr);
+ mp_opt->addr_id, &mp_opt->addr,
+ mp_opt->port);
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
else
hmac = add_addr6_generate_hmac(msk->remote_key,
msk->local_key,
- mp_opt->addr_id, &mp_opt->addr6);
+ mp_opt->addr_id, &mp_opt->addr6,
+ mp_opt->port);
#endif
pr_debug("msk=%p, ahmac=%llu, mp_opt->ahmac=%llu\n",
--
2.30.1
