Prior to calling bind() a program may call connect() on a socket to restrict to a remote peer address. Using connect() is the normal mechanism to specify a remote network peer, so we use that here. In MCTP connect() is only used for bound sockets - send() is not available for MCTP since a tag must be provided for each message. The smctp_type must match between connect() and bind() calls. Signed-off-by: Matt Johnston --- include/net/mctp.h | 5 ++- net/mctp/af_mctp.c | 104 +++++++++++++++++++++++++++++++++++++++++++++++++---- net/mctp/route.c | 6 +++- 3 files changed, 107 insertions(+), 8 deletions(-) diff --git a/include/net/mctp.h b/include/net/mctp.h index 07d458990113d2bc2ca597e40152f3d30e41e5dd..8d3c45bd9cda642af2fc3b3bc403bf36fc8d2990 100644 --- a/include/net/mctp.h +++ b/include/net/mctp.h @@ -69,7 +69,10 @@ struct mctp_sock { /* bind() params */ unsigned int bind_net; - mctp_eid_t bind_addr; + mctp_eid_t bind_local_addr; + mctp_eid_t bind_peer_addr; + unsigned int bind_peer_net; + bool bind_peer_set; __u8 bind_type; /* sendmsg()/recvmsg() uses struct sockaddr_mctp_ext */ diff --git a/net/mctp/af_mctp.c b/net/mctp/af_mctp.c index 7638e22bf03848868768700fdac07f74891dad0d..a390460b2d5fc38555b8a6df45040c167cded628 100644 --- a/net/mctp/af_mctp.c +++ b/net/mctp/af_mctp.c @@ -79,20 +79,40 @@ static int mctp_bind(struct socket *sock, struct sockaddr *addr, int addrlen) goto out_release; } - msk->bind_addr = smctp->smctp_addr.s_addr; + msk->bind_local_addr = smctp->smctp_addr.s_addr; /* MCTP_NET_ANY with a specific EID is resolved to the default net * at bind() time. * For bind_addr=MCTP_ADDR_ANY it is handled specially at route lookup time. */ if (smctp->smctp_network == MCTP_NET_ANY && - msk->bind_addr != MCTP_ADDR_ANY) { + msk->bind_local_addr != MCTP_ADDR_ANY) { msk->bind_net = mctp_default_net(net); } else { msk->bind_net = smctp->smctp_network; } - msk->bind_type = smctp->smctp_type & 0x7f; /* ignore the IC bit */ + /* ignore the IC bit */ + smctp->smctp_type &= 0x7f; + + if (msk->bind_peer_set) { + if (msk->bind_type != smctp->smctp_type) { + /* Prior connect() had a different type */ + return -EINVAL; + } + + if (msk->bind_net == MCTP_NET_ANY) { + /* Restrict to the network passed to connect() */ + msk->bind_net = msk->bind_peer_net; + } + + if (msk->bind_net != msk->bind_peer_net) { + /* connect() had a different net to bind() */ + return -EINVAL; + } + } else { + msk->bind_type = smctp->smctp_type; + } rc = sk->sk_prot->hash(sk); @@ -102,6 +122,67 @@ static int mctp_bind(struct socket *sock, struct sockaddr *addr, int addrlen) return rc; } +/* Used to set a specific peer prior to bind. Not used for outbound + * connections (Tag Owner set) since MCTP is a datagram protocol. + */ +static int mctp_connect(struct socket *sock, struct sockaddr *addr, + int addrlen, int flags) +{ + struct sock *sk = sock->sk; + struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk); + struct net *net = sock_net(&msk->sk); + struct sockaddr_mctp *smctp; + int rc; + + if (addrlen != sizeof(*smctp)) + return -EINVAL; + + if (addr->sa_family != AF_MCTP) + return -EAFNOSUPPORT; + + /* It's a valid sockaddr for MCTP, cast and do protocol checks */ + smctp = (struct sockaddr_mctp *)addr; + + if (!mctp_sockaddr_is_ok(smctp)) + return -EINVAL; + + /* Can't bind by tag */ + if (smctp->smctp_tag) + return -EINVAL; + + /* IC bit must be unset */ + if (smctp->smctp_type & 0x80) + return -EINVAL; + + lock_sock(sk); + + if (sk_hashed(sk)) { + /* bind() already */ + rc = -EADDRINUSE; + goto out_release; + } + + if (msk->bind_peer_set) { + /* connect() already */ + rc = -EADDRINUSE; + goto out_release; + } + + msk->bind_peer_set = true; + msk->bind_peer_addr = smctp->smctp_addr.s_addr; + msk->bind_type = smctp->smctp_type; + if (smctp->smctp_network == MCTP_NET_ANY) + msk->bind_peer_net = mctp_default_net(net); + else + msk->bind_peer_net = smctp->smctp_network; + + rc = 0; + +out_release: + release_sock(sk); + return rc; +} + static int mctp_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) { DECLARE_SOCKADDR(struct sockaddr_mctp *, addr, msg->msg_name); @@ -563,7 +644,7 @@ static const struct proto_ops mctp_dgram_ops = { .family = PF_MCTP, .release = mctp_release, .bind = mctp_bind, - .connect = sock_no_connect, + .connect = mctp_connect, .socketpair = sock_no_socketpair, .accept = sock_no_accept, .getname = sock_no_getname, @@ -630,6 +711,7 @@ static int mctp_sk_init(struct sock *sk) INIT_HLIST_HEAD(&msk->keys); timer_setup(&msk->key_expiry, mctp_sk_expire_keys, 0); + msk->bind_peer_set = false; return 0; } @@ -643,12 +725,17 @@ static int mctp_sk_hash(struct sock *sk) struct net *net = sock_net(sk); struct sock *existing; struct mctp_sock *msk; + mctp_eid_t remote; u32 hash; int rc; msk = container_of(sk, struct mctp_sock, sk); - hash = mctp_bind_hash(msk->bind_type, msk->bind_addr, MCTP_ADDR_ANY); + if (msk->bind_peer_set) + remote = msk->bind_peer_addr; + else + remote = MCTP_ADDR_ANY; + hash = mctp_bind_hash(msk->bind_type, msk->bind_local_addr, remote); mutex_lock(&net->mctp.bind_lock); @@ -656,8 +743,13 @@ static int mctp_sk_hash(struct sock *sk) sk_for_each(existing, &net->mctp.binds[hash]) { struct mctp_sock *mex = container_of(existing, struct mctp_sock, sk); + bool same_peer = (mex->bind_peer_set && msk->bind_peer_set && + mex->bind_peer_addr == msk->bind_peer_addr) || + (!mex->bind_peer_set && !msk->bind_peer_set); + if (mex->bind_type == msk->bind_type && - mex->bind_addr == msk->bind_addr && + mex->bind_local_addr == msk->bind_local_addr && + same_peer && mex->bind_net == msk->bind_net) { rc = -EADDRINUSE; goto out; diff --git a/net/mctp/route.c b/net/mctp/route.c index 8a8c7841d2382717b3c9a6698036d56f64da77f0..3e5b87be312857282947399750566d90c474546c 100644 --- a/net/mctp/route.c +++ b/net/mctp/route.c @@ -63,7 +63,11 @@ static struct mctp_sock *mctp_lookup_bind_details(struct net *net, if (msk->bind_type != type) continue; - if (!mctp_address_matches(msk->bind_addr, dest)) + if (msk->bind_peer_set && + !mctp_address_matches(msk->bind_peer_addr, src)) + continue; + + if (!mctp_address_matches(msk->bind_local_addr, dest)) continue; return msk; -- 2.43.0