rxrpc: Permit multiple service binding
Permit bind() to be called on an AF_RXRPC socket more than once (currently
maximum twice) to bind multiple listening services to it. There are some
restrictions:
(1) All bind() calls involved must have a non-zero service ID.
(2) The service IDs must all be different.
(3) The rest of the address (notably the transport part) must be the same
in all (a single UDP socket is shared).
(4) This must be done before listen() or sendmsg() is called.
This allows someone to connect to the service socket with different service
IDs and lays the foundation for service upgrading.
The service ID used by an incoming call can be extracted from the msg_name
returned by recvmsg().
Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index 1e4ac88..3b982bc 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -144,33 +144,50 @@
lock_sock(&rx->sk);
- if (rx->sk.sk_state != RXRPC_UNBOUND) {
+ switch (rx->sk.sk_state) {
+ case RXRPC_UNBOUND:
+ rx->srx = *srx;
+ local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
+ if (IS_ERR(local)) {
+ ret = PTR_ERR(local);
+ goto error_unlock;
+ }
+
+ if (service_id) {
+ write_lock(&local->services_lock);
+ if (rcu_access_pointer(local->service))
+ goto service_in_use;
+ rx->local = local;
+ rcu_assign_pointer(local->service, rx);
+ write_unlock(&local->services_lock);
+
+ rx->sk.sk_state = RXRPC_SERVER_BOUND;
+ } else {
+ rx->local = local;
+ rx->sk.sk_state = RXRPC_CLIENT_BOUND;
+ }
+ break;
+
+ case RXRPC_SERVER_BOUND:
+ ret = -EINVAL;
+ if (service_id == 0)
+ goto error_unlock;
+ ret = -EADDRINUSE;
+ if (service_id == rx->srx.srx_service)
+ goto error_unlock;
+ ret = -EINVAL;
+ srx->srx_service = rx->srx.srx_service;
+ if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0)
+ goto error_unlock;
+ rx->second_service = service_id;
+ rx->sk.sk_state = RXRPC_SERVER_BOUND2;
+ break;
+
+ default:
ret = -EINVAL;
goto error_unlock;
}
- memcpy(&rx->srx, srx, sizeof(rx->srx));
-
- local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
- if (IS_ERR(local)) {
- ret = PTR_ERR(local);
- goto error_unlock;
- }
-
- if (service_id) {
- write_lock(&local->services_lock);
- if (rcu_access_pointer(local->service))
- goto service_in_use;
- rx->local = local;
- rcu_assign_pointer(local->service, rx);
- write_unlock(&local->services_lock);
-
- rx->sk.sk_state = RXRPC_SERVER_BOUND;
- } else {
- rx->local = local;
- rx->sk.sk_state = RXRPC_CLIENT_BOUND;
- }
-
release_sock(&rx->sk);
_leave(" = 0");
return 0;
@@ -205,6 +222,7 @@
ret = -EADDRNOTAVAIL;
break;
case RXRPC_SERVER_BOUND:
+ case RXRPC_SERVER_BOUND2:
ASSERT(rx->local != NULL);
max = READ_ONCE(rxrpc_max_backlog);
ret = -EINVAL;
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index de98a49..781fbc2 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -61,6 +61,7 @@
RXRPC_CLIENT_UNBOUND, /* Unbound socket used as client */
RXRPC_CLIENT_BOUND, /* client local address bound */
RXRPC_SERVER_BOUND, /* server local address bound */
+ RXRPC_SERVER_BOUND2, /* second server local address bound */
RXRPC_SERVER_LISTENING, /* server listening for connections */
RXRPC_SERVER_LISTEN_DISABLED, /* server listening disabled */
RXRPC_CLOSE, /* socket is being closed */
@@ -142,6 +143,7 @@
u32 min_sec_level; /* minimum security level */
#define RXRPC_SECURITY_MAX RXRPC_SECURITY_ENCRYPT
bool exclusive; /* Exclusive connection for a client socket */
+ u16 second_service; /* Additional service bound to the endpoint */
sa_family_t family; /* Protocol family created with */
struct sockaddr_rxrpc srx; /* local address */
struct sockaddr_rxrpc connect_srx; /* Default client address from connect() */
diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c
index a8515b0..544df53 100644
--- a/net/rxrpc/call_accept.c
+++ b/net/rxrpc/call_accept.c
@@ -341,7 +341,8 @@
/* Get the socket providing the service */
rx = rcu_dereference(local->service);
- if (rx && service_id == rx->srx.srx_service)
+ if (rx && (service_id == rx->srx.srx_service ||
+ service_id == rx->second_service))
goto found_service;
trace_rxrpc_abort("INV", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index 17d79fd..38b99db 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -94,6 +94,7 @@
rwlock_init(&local->services_lock);
local->debug_id = atomic_inc_return(&rxrpc_debug_id);
memcpy(&local->srx, srx, sizeof(*srx));
+ local->srx.srx_service = 0;
}
_leave(" = %p", local);
diff --git a/net/rxrpc/security.c b/net/rxrpc/security.c
index b9f5dbb..e9f4283 100644
--- a/net/rxrpc/security.c
+++ b/net/rxrpc/security.c
@@ -133,7 +133,8 @@
read_lock(&local->services_lock);
rx = rcu_dereference_protected(local->service,
lockdep_is_held(&local->services_lock));
- if (rx && rx->srx.srx_service == conn->service_id)
+ if (rx && (rx->srx.srx_service == conn->service_id ||
+ rx->second_service == conn->service_id))
goto found_service;
/* the service appears to have died */