From cc8feb8edd92d854be552fe4f5e0eeabca40b9ee Mon Sep 17 00:00:00 2001 From: David Howells Date: Mon, 4 Apr 2016 14:00:37 +0100 Subject: [PATCH] rxrpc: Fix exclusive connection handling "Exclusive connections" are meant to be used for a single client call and then scrapped. The idea is to limit the use of the negotiated security context. The current code, however, isn't doing this: it is instead restricting the socket to a single virtual connection and doing all the calls over that. This is changed such that the socket no longer maintains a special virtual connection over which it will do all the calls, but rather gets a new one each time a new exclusive call is made. Further, using a socket option for this is a poor choice. It should be done on sendmsg with a control message marker instead so that calls can be marked exclusive individually. To that end, add RXRPC_EXCLUSIVE_CALL which, if passed to sendmsg() as a control message element, will cause the call to be done on an single-use connection. The socket option (RXRPC_EXCLUSIVE_CONNECTION) still exists and, if set, will override any lack of RXRPC_EXCLUSIVE_CALL being specified so that programs using the setsockopt() will appear to work the same. Signed-off-by: David Howells --- include/linux/rxrpc.h | 3 +- net/rxrpc/af_rxrpc.c | 7 +-- net/rxrpc/ar-internal.h | 7 +-- net/rxrpc/conn_object.c | 105 ++++++++++++++++------------------------ net/rxrpc/output.c | 19 ++++++-- 5 files changed, 64 insertions(+), 77 deletions(-) diff --git a/include/linux/rxrpc.h b/include/linux/rxrpc.h index 1e8f216e2cf1..c68307bc306f 100644 --- a/include/linux/rxrpc.h +++ b/include/linux/rxrpc.h @@ -35,7 +35,7 @@ struct sockaddr_rxrpc { */ #define RXRPC_SECURITY_KEY 1 /* [clnt] set client security key */ #define RXRPC_SECURITY_KEYRING 2 /* [srvr] set ring of server security keys */ -#define RXRPC_EXCLUSIVE_CONNECTION 3 /* [clnt] use exclusive RxRPC connection */ +#define RXRPC_EXCLUSIVE_CONNECTION 3 /* Deprecated; use RXRPC_EXCLUSIVE_CALL instead */ #define RXRPC_MIN_SECURITY_LEVEL 4 /* minimum security level */ /* @@ -52,6 +52,7 @@ struct sockaddr_rxrpc { #define RXRPC_LOCAL_ERROR 7 /* -r: local error generated [terminal] */ #define RXRPC_NEW_CALL 8 /* -r: [Service] new incoming call notification */ #define RXRPC_ACCEPT 9 /* s-: [Service] accept request */ +#define RXRPC_EXCLUSIVE_CALL 10 /* s-: Call should be on exclusive connection */ /* * RxRPC security levels diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c index 48b45a0280c0..73f5c553eef4 100644 --- a/net/rxrpc/af_rxrpc.c +++ b/net/rxrpc/af_rxrpc.c @@ -494,7 +494,7 @@ static int rxrpc_setsockopt(struct socket *sock, int level, int optname, ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNBOUND) goto error; - set_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags); + rx->exclusive = true; goto success; case RXRPC_SECURITY_KEY: @@ -669,11 +669,6 @@ static int rxrpc_release_sock(struct sock *sk) flush_workqueue(rxrpc_workqueue); rxrpc_purge_queue(&sk->sk_receive_queue); - if (rx->conn) { - rxrpc_put_connection(rx->conn); - rx->conn = NULL; - } - if (rx->local) { rxrpc_put_local(rx->local); rx->local = NULL; diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index efe6673deb28..4ca99445e0b7 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -37,6 +37,8 @@ struct rxrpc_crypt { #define rxrpc_queue_call(CALL) rxrpc_queue_work(&(CALL)->processor) #define rxrpc_queue_conn(CONN) rxrpc_queue_work(&(CONN)->processor) +struct rxrpc_connection; + /* * sk_state for RxRPC sockets */ @@ -57,7 +59,6 @@ struct rxrpc_sock { struct sock sk; rxrpc_interceptor_t interceptor; /* kernel service Rx interceptor function */ struct rxrpc_local *local; /* local endpoint */ - struct rxrpc_connection *conn; /* exclusive virtual connection */ struct list_head listen_link; /* link in the local endpoint's listen list */ struct list_head secureq; /* calls awaiting connection security clearance */ struct list_head acceptq; /* calls awaiting acceptance */ @@ -66,13 +67,13 @@ struct rxrpc_sock { struct rb_root calls; /* outstanding calls on this socket */ unsigned long flags; #define RXRPC_SOCK_CONNECTED 0 /* connect_srx is set */ -#define RXRPC_SOCK_EXCLUSIVE_CONN 1 /* exclusive connection for a client socket */ rwlock_t call_lock; /* lock for calls */ u32 min_sec_level; /* minimum security level */ #define RXRPC_SECURITY_MAX RXRPC_SECURITY_ENCRYPT + bool exclusive; /* Exclusive connection for a client socket */ + sa_family_t family; /* Protocol family created with */ struct sockaddr_rxrpc srx; /* local address */ struct sockaddr_rxrpc connect_srx; /* Default client address from connect() */ - sa_family_t family; /* protocol family created with */ }; #define rxrpc_sk(__sk) container_of((__sk), struct rxrpc_sock, sk) diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c index c6787b6f459f..6164373d6ce3 100644 --- a/net/rxrpc/conn_object.c +++ b/net/rxrpc/conn_object.c @@ -328,71 +328,57 @@ static int rxrpc_connect_exclusive(struct rxrpc_sock *rx, _enter(""); - conn = rx->conn; + conn = rxrpc_alloc_connection(gfp); if (!conn) { - /* not yet present - create a candidate for a new connection - * and then redo the check */ - conn = rxrpc_alloc_connection(gfp); - if (!conn) { - _leave(" = -ENOMEM"); - return -ENOMEM; - } - - conn->trans = trans; - conn->bundle = NULL; - conn->params = *cp; - conn->proto.local = cp->local; - conn->proto.epoch = rxrpc_epoch; - conn->proto.cid = 0; - conn->proto.in_clientflag = 0; - conn->proto.family = cp->peer->srx.transport.family; - conn->out_clientflag = RXRPC_CLIENT_INITIATED; - conn->state = RXRPC_CONN_CLIENT; - conn->avail_calls = RXRPC_MAXCALLS - 1; - - key_get(conn->params.key); - - ret = rxrpc_init_client_conn_security(conn); - if (ret < 0) { - key_put(conn->params.key); - kfree(conn); - _leave(" = %d [key]", ret); - return ret; - } - - write_lock_bh(&rxrpc_connection_lock); - list_add_tail(&conn->link, &rxrpc_connections); - write_unlock_bh(&rxrpc_connection_lock); - - spin_lock(&trans->client_lock); - atomic_inc(&trans->usage); - - _net("CONNECT EXCL new %d on TRANS %d", - conn->debug_id, conn->trans->debug_id); - - rxrpc_assign_connection_id(conn); - rx->conn = conn; - } else { - spin_lock(&trans->client_lock); + _leave(" = -ENOMEM"); + return -ENOMEM; } - /* we've got a connection with a free channel and we can now attach the - * call to it - * - we're holding the transport's client lock - * - we're holding a reference on the connection - */ - for (chan = 0; chan < RXRPC_MAXCALLS; chan++) - if (!conn->channels[chan]) - goto found_channel; - goto no_free_channels; + conn->trans = trans; + conn->bundle = NULL; + conn->params = *cp; + conn->proto.local = cp->local; + conn->proto.epoch = rxrpc_epoch; + conn->proto.cid = 0; + conn->proto.in_clientflag = 0; + conn->proto.family = cp->peer->srx.transport.family; + conn->out_clientflag = RXRPC_CLIENT_INITIATED; + conn->state = RXRPC_CONN_CLIENT; + conn->avail_calls = RXRPC_MAXCALLS - 1; -found_channel: + key_get(conn->params.key); + + ret = rxrpc_init_client_conn_security(conn); + if (ret < 0) { + key_put(conn->params.key); + kfree(conn); + _leave(" = %d [key]", ret); + return ret; + } + + write_lock_bh(&rxrpc_connection_lock); + list_add_tail(&conn->link, &rxrpc_connections); + write_unlock_bh(&rxrpc_connection_lock); + + spin_lock(&trans->client_lock); + atomic_inc(&trans->usage); + + _net("CONNECT EXCL new %d on TRANS %d", + conn->debug_id, conn->trans->debug_id); + + rxrpc_assign_connection_id(conn); + + /* Since no one else can use the connection, we just use the first + * channel. + */ + chan = 0; atomic_inc(&conn->usage); conn->channels[chan] = call; + conn->call_counter = 1; call->conn = conn; call->channel = chan; call->cid = conn->proto.cid | chan; - call->call_id = ++conn->call_counter; + call->call_id = 1; _net("CONNECT client on conn %d chan %d as call %x", conn->debug_id, chan, call->call_id); @@ -402,11 +388,6 @@ found_channel: rxrpc_add_call_ID_to_conn(conn, call); _leave(" = 0"); return 0; - -no_free_channels: - spin_unlock(&trans->client_lock); - _leave(" = -ENOSR"); - return -ENOSR; } /* @@ -427,7 +408,7 @@ int rxrpc_connect_call(struct rxrpc_sock *rx, _enter("%p,%lx,", rx, call->user_call_ID); - if (test_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags)) + if (cp->exclusive) return rxrpc_connect_exclusive(rx, cp, trans, call, gfp); spin_lock(&trans->client_lock); diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c index becbaa7c0a7c..6f8ab0ef839f 100644 --- a/net/rxrpc/output.c +++ b/net/rxrpc/output.c @@ -35,7 +35,8 @@ static int rxrpc_send_data(struct rxrpc_sock *rx, static int rxrpc_sendmsg_cmsg(struct msghdr *msg, unsigned long *user_call_ID, enum rxrpc_command *command, - u32 *abort_code) + u32 *abort_code, + bool *_exclusive) { struct cmsghdr *cmsg; bool got_user_ID = false; @@ -93,6 +94,11 @@ static int rxrpc_sendmsg_cmsg(struct msghdr *msg, return -EINVAL; break; + case RXRPC_EXCLUSIVE_CALL: + *_exclusive = true; + if (len != 0) + return -EINVAL; + break; default: return -EINVAL; } @@ -131,7 +137,7 @@ static void rxrpc_send_abort(struct rxrpc_call *call, u32 abort_code) */ static struct rxrpc_call * rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, - unsigned long user_call_ID) + unsigned long user_call_ID, bool exclusive) { struct rxrpc_conn_parameters cp; struct rxrpc_conn_bundle *bundle; @@ -155,7 +161,7 @@ rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, cp.local = rx->local; cp.key = rx->key; cp.security_level = rx->min_sec_level; - cp.exclusive = test_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags); + cp.exclusive = rx->exclusive | exclusive; cp.service_id = srx->srx_service; trans = rxrpc_name_to_transport(&cp, msg->msg_name, msg->msg_namelen, GFP_KERNEL); @@ -201,12 +207,14 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len) enum rxrpc_command cmd; struct rxrpc_call *call; unsigned long user_call_ID = 0; + bool exclusive = false; u32 abort_code = 0; int ret; _enter(""); - ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code); + ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code, + &exclusive); if (ret < 0) return ret; @@ -224,7 +232,8 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len) if (!call) { if (cmd != RXRPC_CMD_SEND_DATA) return -EBADSLT; - call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID); + call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID, + exclusive); if (IS_ERR(call)) return PTR_ERR(call); }