diff options
Diffstat (limited to 'net/ipv4/tcp.c')
-rw-r--r-- | net/ipv4/tcp.c | 292 |
1 files changed, 282 insertions, 10 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 1272a88c2a63..565406287f6f 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -363,6 +363,71 @@ static int retrans_to_secs(u8 retrans, int timeout, int rto_max) return period; } +/* Address-family independent initialization for a tcp_sock. + * + * NOTE: A lot of things set to zero explicitly by call to + * sk_alloc() so need not be done here. + */ +void tcp_init_sock(struct sock *sk) +{ + struct inet_connection_sock *icsk = inet_csk(sk); + struct tcp_sock *tp = tcp_sk(sk); + + skb_queue_head_init(&tp->out_of_order_queue); + tcp_init_xmit_timers(sk); + tcp_prequeue_init(tp); + + icsk->icsk_rto = TCP_TIMEOUT_INIT; + tp->mdev = TCP_TIMEOUT_INIT; + + /* So many TCP implementations out there (incorrectly) count the + * initial SYN frame in their delayed-ACK and congestion control + * algorithms that we must have the following bandaid to talk + * efficiently to them. -DaveM + */ + tp->snd_cwnd = TCP_INIT_CWND; + + /* See draft-stevens-tcpca-spec-01 for discussion of the + * initialization of these values. + */ + tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; + tp->snd_cwnd_clamp = ~0; + tp->mss_cache = TCP_MSS_DEFAULT; + + tp->reordering = sysctl_tcp_reordering; + tcp_enable_early_retrans(tp); + icsk->icsk_ca_ops = &tcp_init_congestion_ops; + + sk->sk_state = TCP_CLOSE; + + sk->sk_write_space = sk_stream_write_space; + sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); + + icsk->icsk_sync_mss = tcp_sync_mss; + + /* TCP Cookie Transactions */ + if (sysctl_tcp_cookie_size > 0) { + /* Default, cookies without s_data_payload. */ + tp->cookie_values = + kzalloc(sizeof(*tp->cookie_values), + sk->sk_allocation); + if (tp->cookie_values != NULL) + kref_init(&tp->cookie_values->kref); + } + /* Presumed zeroed, in order of appearance: + * cookie_in_always, cookie_out_never, + * s_data_constant, s_data_in, s_data_out + */ + sk->sk_sndbuf = sysctl_tcp_wmem[1]; + sk->sk_rcvbuf = sysctl_tcp_rmem[1]; + + local_bh_disable(); + sock_update_memcg(sk); + sk_sockets_allocated_inc(sk); + local_bh_enable(); +} +EXPORT_SYMBOL(tcp_init_sock); + /* * Wait for a TCP event. * @@ -784,9 +849,10 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffse while (psize > 0) { struct sk_buff *skb = tcp_write_queue_tail(sk); struct page *page = pages[poffset / PAGE_SIZE]; - int copy, i, can_coalesce; + int copy, i; int offset = poffset % PAGE_SIZE; int size = min_t(size_t, psize, PAGE_SIZE - offset); + bool can_coalesce; if (!tcp_send_head(sk) || (copy = size_goal - skb->len) <= 0) { new_segment: @@ -912,6 +978,39 @@ static inline int select_size(const struct sock *sk, bool sg) return tmp; } +static int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size) +{ + struct sk_buff *skb; + struct tcphdr *th; + bool fragstolen; + + skb = alloc_skb(size + sizeof(*th), sk->sk_allocation); + if (!skb) + goto err; + + th = (struct tcphdr *)skb_put(skb, sizeof(*th)); + skb_reset_transport_header(skb); + memset(th, 0, sizeof(*th)); + + if (memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size)) + goto err_free; + + TCP_SKB_CB(skb)->seq = tcp_sk(sk)->rcv_nxt; + TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq + size; + TCP_SKB_CB(skb)->ack_seq = tcp_sk(sk)->snd_una - 1; + + if (tcp_queue_rcv(sk, skb, sizeof(*th), &fragstolen)) { + WARN_ON_ONCE(fragstolen); /* should not happen */ + __kfree_skb(skb); + } + return size; + +err_free: + kfree_skb(skb); +err: + return -ENOMEM; +} + int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t size) { @@ -919,7 +1018,7 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; int iovlen, flags, err, copied; - int mss_now, size_goal; + int mss_now = 0, size_goal; bool sg; long timeo; @@ -933,6 +1032,19 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, if ((err = sk_stream_wait_connect(sk, &timeo)) != 0) goto out_err; + if (unlikely(tp->repair)) { + if (tp->repair_queue == TCP_RECV_QUEUE) { + copied = tcp_send_rcvq(sk, msg, size); + goto out; + } + + err = -EINVAL; + if (tp->repair_queue == TCP_NO_QUEUE) + goto out_err; + + /* 'common' sending to sendq */ + } + /* This should be in poll */ clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); @@ -1089,7 +1201,7 @@ new_segment: if ((seglen -= copy) == 0 && iovlen == 0) goto out; - if (skb->len < max || (flags & MSG_OOB)) + if (skb->len < max || (flags & MSG_OOB) || unlikely(tp->repair)) continue; if (forced_push(tp)) { @@ -1102,7 +1214,7 @@ new_segment: wait_for_sndbuf: set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); wait_for_memory: - if (copied) + if (copied && likely(!tp->repair)) tcp_push(sk, flags & ~MSG_MORE, mss_now, TCP_NAGLE_PUSH); if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) @@ -1113,7 +1225,7 @@ wait_for_memory: } out: - if (copied) + if (copied && likely(!tp->repair)) tcp_push(sk, flags, mss_now, tp->nonagle); release_sock(sk); return copied; @@ -1187,6 +1299,24 @@ static int tcp_recv_urg(struct sock *sk, struct msghdr *msg, int len, int flags) return -EAGAIN; } +static int tcp_peek_sndq(struct sock *sk, struct msghdr *msg, int len) +{ + struct sk_buff *skb; + int copied = 0, err = 0; + + /* XXX -- need to support SO_PEEK_OFF */ + + skb_queue_walk(&sk->sk_write_queue, skb) { + err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, skb->len); + if (err) + break; + + copied += skb->len; + } + + return err ?: copied; +} + /* Clean up the receive buffer for full frames taken by the user, * then send an ACK if necessary. COPIED is the number of bytes * tcp_recvmsg has given to the user so far, it speeds up the @@ -1432,6 +1562,21 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, if (flags & MSG_OOB) goto recv_urg; + if (unlikely(tp->repair)) { + err = -EPERM; + if (!(flags & MSG_PEEK)) + goto out; + + if (tp->repair_queue == TCP_SEND_QUEUE) + goto recv_sndq; + + err = -EINVAL; + if (tp->repair_queue == TCP_NO_QUEUE) + goto out; + + /* 'common' recv queue MSG_PEEK-ing */ + } + seq = &tp->copied_seq; if (flags & MSG_PEEK) { peek_seq = tp->copied_seq; @@ -1783,6 +1928,10 @@ out: recv_urg: err = tcp_recv_urg(sk, msg, len, flags); goto out; + +recv_sndq: + err = tcp_peek_sndq(sk, msg, len); + goto out; } EXPORT_SYMBOL(tcp_recvmsg); @@ -1935,7 +2084,9 @@ void tcp_close(struct sock *sk, long timeout) * advertise a zero window, then kill -9 the FTP client, wheee... * Note: timeout is always zero in such a case. */ - if (data_was_unread) { + if (unlikely(tcp_sk(sk)->repair)) { + sk->sk_prot->disconnect(sk, 0); + } else if (data_was_unread) { /* Unread data was tossed, zap the connection. */ NET_INC_STATS_USER(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE); tcp_set_state(sk, TCP_CLOSE); @@ -2074,6 +2225,8 @@ int tcp_disconnect(struct sock *sk, int flags) /* ABORT function of RFC793 */ if (old_state == TCP_LISTEN) { inet_csk_listen_stop(sk); + } else if (unlikely(tp->repair)) { + sk->sk_err = ECONNABORTED; } else if (tcp_need_reset(old_state) || (tp->snd_nxt != tp->write_seq && (1 << old_state) & (TCPF_CLOSING | TCPF_LAST_ACK))) { @@ -2125,6 +2278,54 @@ int tcp_disconnect(struct sock *sk, int flags) } EXPORT_SYMBOL(tcp_disconnect); +static inline int tcp_can_repair_sock(struct sock *sk) +{ + return capable(CAP_NET_ADMIN) && + ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_ESTABLISHED)); +} + +static int tcp_repair_options_est(struct tcp_sock *tp, + struct tcp_repair_opt __user *optbuf, unsigned int len) +{ + struct tcp_repair_opt opt; + + while (len >= sizeof(opt)) { + if (copy_from_user(&opt, optbuf, sizeof(opt))) + return -EFAULT; + + optbuf++; + len -= sizeof(opt); + + switch (opt.opt_code) { + case TCPOPT_MSS: + tp->rx_opt.mss_clamp = opt.opt_val; + break; + case TCPOPT_WINDOW: + if (opt.opt_val > 14) + return -EFBIG; + + tp->rx_opt.snd_wscale = opt.opt_val; + break; + case TCPOPT_SACK_PERM: + if (opt.opt_val != 0) + return -EINVAL; + + tp->rx_opt.sack_ok |= TCP_SACK_SEEN; + if (sysctl_tcp_fack) + tcp_enable_fack(tp); + break; + case TCPOPT_TIMESTAMP: + if (opt.opt_val != 0) + return -EINVAL; + + tp->rx_opt.tstamp_ok = 1; + break; + } + } + + return 0; +} + /* * Socket option code for TCP. */ @@ -2295,6 +2496,55 @@ static int do_tcp_setsockopt(struct sock *sk, int level, err = -EINVAL; else tp->thin_dupack = val; + if (tp->thin_dupack) + tcp_disable_early_retrans(tp); + break; + + case TCP_REPAIR: + if (!tcp_can_repair_sock(sk)) + err = -EPERM; + else if (val == 1) { + tp->repair = 1; + sk->sk_reuse = SK_FORCE_REUSE; + tp->repair_queue = TCP_NO_QUEUE; + } else if (val == 0) { + tp->repair = 0; + sk->sk_reuse = SK_NO_REUSE; + tcp_send_window_probe(sk); + } else + err = -EINVAL; + + break; + + case TCP_REPAIR_QUEUE: + if (!tp->repair) + err = -EPERM; + else if (val < TCP_QUEUES_NR) + tp->repair_queue = val; + else + err = -EINVAL; + break; + + case TCP_QUEUE_SEQ: + if (sk->sk_state != TCP_CLOSE) + err = -EPERM; + else if (tp->repair_queue == TCP_SEND_QUEUE) + tp->write_seq = val; + else if (tp->repair_queue == TCP_RECV_QUEUE) + tp->rcv_nxt = val; + else + err = -EINVAL; + break; + + case TCP_REPAIR_OPTIONS: + if (!tp->repair) + err = -EINVAL; + else if (sk->sk_state == TCP_ESTABLISHED) + err = tcp_repair_options_est(tp, + (struct tcp_repair_opt __user *)optval, + optlen); + else + err = -EPERM; break; case TCP_CORK: @@ -2530,6 +2780,8 @@ static int do_tcp_getsockopt(struct sock *sk, int level, val = tp->mss_cache; if (!val && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) val = tp->rx_opt.user_mss; + if (tp->repair) + val = tp->rx_opt.mss_clamp; break; case TCP_NODELAY: val = !!(tp->nonagle&TCP_NAGLE_OFF); @@ -2632,6 +2884,26 @@ static int do_tcp_getsockopt(struct sock *sk, int level, val = tp->thin_dupack; break; + case TCP_REPAIR: + val = tp->repair; + break; + + case TCP_REPAIR_QUEUE: + if (tp->repair) + val = tp->repair_queue; + else + return -EINVAL; + break; + + case TCP_QUEUE_SEQ: + if (tp->repair_queue == TCP_SEND_QUEUE) + val = tp->write_seq; + else if (tp->repair_queue == TCP_RECV_QUEUE) + val = tp->rcv_nxt; + else + return -EINVAL; + break; + case TCP_USER_TIMEOUT: val = jiffies_to_msecs(icsk->icsk_user_timeout); break; @@ -2675,7 +2947,7 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, { struct sk_buff *segs = ERR_PTR(-EINVAL); struct tcphdr *th; - unsigned thlen; + unsigned int thlen; unsigned int seq; __be32 delta; unsigned int oldlen; @@ -3033,9 +3305,9 @@ int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp, struct scatterlist sg; const struct tcphdr *tp = tcp_hdr(skb); struct hash_desc *desc = &hp->md5_desc; - unsigned i; - const unsigned head_data_len = skb_headlen(skb) > header_len ? - skb_headlen(skb) - header_len : 0; + unsigned int i; + const unsigned int head_data_len = skb_headlen(skb) > header_len ? + skb_headlen(skb) - header_len : 0; const struct skb_shared_info *shi = skb_shinfo(skb); struct sk_buff *frag_iter; |