From 5e8f3f703ae4e4af65e2695e486b3cd198328863 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Thu, 12 Mar 2009 09:49:17 +0000 Subject: [PATCH] sctp: simplify sctp listening code sctp_inet_listen() call is split between UDP and TCP style. Looking at the code, the two functions are almost the same and can be merged into a single helper. This also fixes a bug that was fixed in the UDP function, but missed in the TCP function. Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/sctp/socket.c | 152 +++++++++++++++------------------------------- 1 file changed, 50 insertions(+), 102 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index bbd3cd238d7f..5fb3a8c9792e 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -5843,37 +5843,28 @@ static int sctp_get_port(struct sock *sk, unsigned short snum) } /* - * 3.1.3 listen() - UDP Style Syntax - * - * By default, new associations are not accepted for UDP style sockets. - * An application uses listen() to mark a socket as being able to - * accept new associations. + * Move a socket to LISTENING state. */ -SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog) +SCTP_STATIC int sctp_listen_start(struct sock *sk, int backlog) { struct sctp_sock *sp = sctp_sk(sk); struct sctp_endpoint *ep = sp->ep; + struct crypto_hash *tfm = NULL; - /* Only UDP style sockets that are not peeled off are allowed to - * listen(). - */ - if (!sctp_style(sk, UDP)) - return -EINVAL; - - /* If backlog is zero, disable listening. */ - if (!backlog) { - if (sctp_sstate(sk, CLOSED)) - return 0; - - sctp_unhash_endpoint(ep); - sk->sk_state = SCTP_SS_CLOSED; - return 0; + /* Allocate HMAC for generating cookie. */ + if (!sctp_sk(sk)->hmac && sctp_hmac_alg) { + tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(tfm)) { + if (net_ratelimit()) { + printk(KERN_INFO + "SCTP: failed to load transform for %s: %ld\n", + sctp_hmac_alg, PTR_ERR(tfm)); + } + return -ENOSYS; + } + sctp_sk(sk)->hmac = tfm; } - /* Return if we are already listening. */ - if (sctp_sstate(sk, LISTENING)) - return 0; - /* * If a bind() or sctp_bindx() is not called prior to a listen() * call that allows new associations to be accepted, the system @@ -5884,7 +5875,6 @@ SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog) * extensions draft, but follows the practice as seen in TCP * sockets. * - * Additionally, turn off fastreuse flag since we are not listening */ sk->sk_state = SCTP_SS_LISTENING; if (!ep->base.bind_addr.port) { @@ -5895,113 +5885,71 @@ SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog) sk->sk_state = SCTP_SS_CLOSED; return -EADDRINUSE; } - sctp_sk(sk)->bind_hash->fastreuse = 0; } - sctp_hash_endpoint(ep); - return 0; -} - -/* - * 4.1.3 listen() - TCP Style Syntax - * - * Applications uses listen() to ready the SCTP endpoint for accepting - * inbound associations. - */ -SCTP_STATIC int sctp_stream_listen(struct sock *sk, int backlog) -{ - struct sctp_sock *sp = sctp_sk(sk); - struct sctp_endpoint *ep = sp->ep; - - /* If backlog is zero, disable listening. */ - if (!backlog) { - if (sctp_sstate(sk, CLOSED)) - return 0; - - sctp_unhash_endpoint(ep); - sk->sk_state = SCTP_SS_CLOSED; - return 0; - } - - if (sctp_sstate(sk, LISTENING)) - return 0; - - /* - * If a bind() or sctp_bindx() is not called prior to a listen() - * call that allows new associations to be accepted, the system - * picks an ephemeral port and will choose an address set equivalent - * to binding with a wildcard address. - * - * This is not currently spelled out in the SCTP sockets - * extensions draft, but follows the practice as seen in TCP - * sockets. - */ - sk->sk_state = SCTP_SS_LISTENING; - if (!ep->base.bind_addr.port) { - if (sctp_autobind(sk)) - return -EAGAIN; - } else - sctp_sk(sk)->bind_hash->fastreuse = 0; - sk->sk_max_ack_backlog = backlog; sctp_hash_endpoint(ep); return 0; } /* + * 4.1.3 / 5.1.3 listen() + * + * By default, new associations are not accepted for UDP style sockets. + * An application uses listen() to mark a socket as being able to + * accept new associations. + * + * On TCP style sockets, applications use listen() to ready the SCTP + * endpoint for accepting inbound associations. + * + * On both types of endpoints a backlog of '0' disables listening. + * * Move a socket to LISTENING state. */ int sctp_inet_listen(struct socket *sock, int backlog) { struct sock *sk = sock->sk; - struct crypto_hash *tfm = NULL; + struct sctp_endpoint *ep = sctp_sk(sk)->ep; int err = -EINVAL; if (unlikely(backlog < 0)) - goto out; + return err; sctp_lock_sock(sk); + /* Peeled-off sockets are not allowed to listen(). */ + if (sctp_style(sk, UDP_HIGH_BANDWIDTH)) + goto out; + if (sock->state != SS_UNCONNECTED) goto out; - /* Allocate HMAC for generating cookie. */ - if (!sctp_sk(sk)->hmac && sctp_hmac_alg) { - tfm = crypto_alloc_hash(sctp_hmac_alg, 0, CRYPTO_ALG_ASYNC); - if (IS_ERR(tfm)) { - if (net_ratelimit()) { - printk(KERN_INFO - "SCTP: failed to load transform for %s: %ld\n", - sctp_hmac_alg, PTR_ERR(tfm)); - } - err = -ENOSYS; + /* If backlog is zero, disable listening. */ + if (!backlog) { + if (sctp_sstate(sk, CLOSED)) goto out; - } - } - switch (sock->type) { - case SOCK_SEQPACKET: - err = sctp_seqpacket_listen(sk, backlog); - break; - case SOCK_STREAM: - err = sctp_stream_listen(sk, backlog); - break; - default: - break; + err = 0; + sctp_unhash_endpoint(ep); + sk->sk_state = SCTP_SS_CLOSED; + if (sk->sk_reuse) + sctp_sk(sk)->bind_hash->fastreuse = 1; + goto out; } - if (err) - goto cleanup; + /* If we are already listening, just update the backlog */ + if (sctp_sstate(sk, LISTENING)) + sk->sk_max_ack_backlog = backlog; + else { + err = sctp_listen_start(sk, backlog); + if (err) + goto out; + } - /* Store away the transform reference. */ - if (!sctp_sk(sk)->hmac) - sctp_sk(sk)->hmac = tfm; + err = 0; out: sctp_release_sock(sk); return err; -cleanup: - crypto_free_hash(tfm); - goto out; } /* -- 2.20.1