X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/4c04137d73637107669e02b21f890387aaa2ef34..1ccd5f670a432f98e94b384dd169a1a760dced9a:/src/src/ip.c diff --git a/src/src/ip.c b/src/src/ip.c index 8bb6bed1f..eb01229e6 100644 --- a/src/src/ip.c +++ b/src/src/ip.c @@ -2,7 +2,7 @@ * Exim - an Internet mail transport agent * *************************************************/ -/* Copyright (c) University of Cambridge 1995 - 2016 */ +/* Copyright (c) University of Cambridge 1995 - 2017 */ /* See the file NOTICE for conditions of use and distribution. */ /* Functions for doing things with sockets. With the advent of IPv6 this has @@ -175,14 +175,15 @@ Arguments: address the remote address, in text form port the remote port timeout a timeout (zero for indefinite timeout) - fastopen TRUE iff TCP_FASTOPEN can be used + fastopen non-null iff TCP_FASTOPEN can be used; may indicate early-data to + be sent in SYN segment Returns: 0 on success; -1 on failure, with errno set */ int ip_connect(int sock, int af, const uschar *address, int port, int timeout, - BOOL fastopen) + const blob * fastopen) { struct sockaddr_in s_in4; struct sockaddr *s_ptr; @@ -228,25 +229,51 @@ if (timeout > 0) alarm(timeout); /* TCP Fast Open, if the system has a cookie from a previous call to this peer, can send data in the SYN packet. The peer can send data before it gets our ACK of its SYN,ACK - the latter is useful for -the SMTP banner. Is there any usage where the former might be? -We might extend the ip_connect() args for data if so. For now, -connect in FASTOPEN mode but with zero data. -*/ +the SMTP banner. Other (than SMTP) cases of TCP connections can +possibly use the data-on-syn, so support that too. */ if (fastopen) { - if ( (rc = sendto(sock, NULL, 0, MSG_FASTOPEN, s_ptr, s_len)) < 0 - && errno == EOPNOTSUPP - ) + if ((rc = sendto(sock, fastopen->data, fastopen->len, + MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0) + /* seen for with-data, experimental TFO option, with-cookie case */ + { + DEBUG(D_transport|D_v) debug_printf("TFO mode connection attempt, %s data\n", + fastopen->len > 0 ? "with" : "no"); + tcp_out_fastopen = fastopen->len > 0 ? 2 : 1; + } + else if (errno == EINPROGRESS) /* expected for nonready peer */ + /* seen for no-data, proper TFO option, both cookie-request and with-cookie cases */ + /* apparently no visibility of the diffference at this point */ + /* with netwk delay, post-conn tcp_info sees unacked 1 for R, 2 for C; code in smtp_out.c */ + /* ? older Experimental TFO option behaviour ? */ + { /* queue unsent data */ + if (!fastopen->data) + { + tcp_out_fastopen = 1; /* we tried; unknown if useful yet */ + rc = 0; + } + else if ( (rc = send(sock, fastopen->data, fastopen->len, 0)) < 0 + && errno == EINPROGRESS /* expected for nonready peer */ + ) + rc = 0; + } + else if(errno == EOPNOTSUPP) { DEBUG(D_transport) debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n"); - rc = connect(sock, s_ptr, s_len); + goto legacy_connect; } } else #endif - rc = connect(sock, s_ptr, s_len); + { +legacy_connect: + if ((rc = connect(sock, s_ptr, s_len)) >= 0) + if ( fastopen && fastopen->data && fastopen->len + && send(sock, fastopen->data, fastopen->len, 0) < 0) + rc = -1; + } save_errno = errno; alarm(0); @@ -289,15 +316,17 @@ Arguments: address the remote address, in text form portlo,porthi the remote port range timeout a timeout - connhost if not NULL, host_item filled in with connection details + connhost if not NULL, host_item to be filled in with connection details errstr pointer for allocated string on error + fastopen with SOCK_STREAM, if non-null, request TCP Fast Open. + Additionally, optional early-data to send Return: socket fd, or -1 on failure (having allocated an error string) */ int ip_connectedsocket(int type, const uschar * hostname, int portlo, int porthi, - int timeout, host_item * connhost, uschar ** errstr) + int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen) { int namelen, port; host_item shost; @@ -358,7 +387,7 @@ for (h = &shost; h; h = h->next) } for(port = portlo; port <= porthi; port++) - if (ip_connect(fd, af, h->address, port, timeout, type == SOCK_STREAM) == 0) + if (ip_connect(fd, af, h->address, port, timeout, fastopen) == 0) { if (fd != fd6) close(fd6); if (fd != fd4) close(fd4); @@ -380,6 +409,7 @@ bad: } +/*XXX TFO? */ int ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo) { @@ -400,7 +430,7 @@ if (scan != 3) } return ip_connectedsocket(SOCK_STREAM, hostname, portlow, porthigh, - tmo, NULL, errstr); + tmo, NULL, errstr, NULL); } int @@ -456,7 +486,7 @@ ip_keepalive(int sock, const uschar *address, BOOL torf) { int fodder = 1; if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, - (uschar *)(&fodder), sizeof(fodder)) != 0) + US (&fodder), sizeof(fodder)) != 0) log_write(0, LOG_MAIN, "setsockopt(SO_KEEPALIVE) on connection %s %s " "failed: %s", torf? "to":"from", address, strerror(errno)); } @@ -491,7 +521,7 @@ if (time_left <= 0) do { - struct timeval tv = { time_left, 0 }; + struct timeval tv = { .tv_sec = time_left, .tv_usec = 0 }; FD_ZERO (&select_inset); FD_SET (fd, &select_inset);