X-Git-Url: https://git.exim.org/users/jgh/exim.git/blobdiff_plain/74f1a42304ce056cf979d22fb970faae161e3ab2..99bfcf2b678e7bd8125a7eb44409e46549bfc111:/src/src/ip.c diff --git a/src/src/ip.c b/src/src/ip.c index 555dc2d84..a5958e95e 100644 --- a/src/src/ip.c +++ b/src/src/ip.c @@ -3,6 +3,7 @@ *************************************************/ /* Copyright (c) University of Cambridge 1995 - 2018 */ +/* Copyright (c) The Exim Maintainers 2020 */ /* See the file NOTICE for conditions of use and distribution. */ /* Functions for doing things with sockets. With the advent of IPv6 this has @@ -14,6 +15,12 @@ different places in the code where sockets are used. */ #include "exim.h" +#if defined(TCP_FASTOPEN) +# if defined(MSG_FASTOPEN) || defined(EXIM_TFO_CONNECTX) || defined(EXIM_TFO_FREEBSD) +# define EXIM_SUPPORT_TFO +# endif +#endif + /************************************************* * Create a socket * *************************************************/ @@ -160,26 +167,6 @@ return bind(sock, (struct sockaddr *)&sin, s_len); -/************************************************* -*************************************************/ - -#ifdef EXIM_TFO_PROBE -void -tfo_probe(void) -{ -# ifdef TCP_FASTOPEN -int sock, backlog = 5; - -if ( (sock = socket(SOCK_STREAM, AF_INET, 0)) < 0 - && setsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &backlog, sizeof(backlog)) - ) - tcp_fastopen_ok = TRUE; -close(sock); -# endif -} -#endif - - /************************************************* * Connect socket to remote host * *************************************************/ @@ -196,7 +183,7 @@ Arguments: port the remote port timeout a timeout (zero for indefinite timeout) fastopen_blob non-null iff TCP_FASTOPEN can be used; may indicate early-data to - be sent in SYN segment + be sent in SYN segment. Any such data must be idempotent. Returns: 0 on success; -1 on failure, with errno set */ @@ -243,57 +230,123 @@ timer, thereby allowing the inbuilt OS timeout to operate. */ callout_address = string_sprintf("[%s]:%d", address, port); sigalrm_seen = FALSE; -if (timeout > 0) alarm(timeout); +if (timeout > 0) ALARM(timeout); -#if defined(TCP_FASTOPEN) && defined(MSG_FASTOPEN) +#ifdef EXIM_SUPPORT_TFO /* 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. Other (than SMTP) cases of TCP connections can -possibly use the data-on-syn, so support that too. */ +possibly use the data-on-syn, so support that too. */ -if (fastopen_blob && tcp_fastopen_ok) +if (fastopen_blob && f.tcp_fastopen_ok) { +# ifdef MSG_FASTOPEN + /* This is a Linux implementation. */ + if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len, MSG_FASTOPEN | MSG_DONTWAIT, s_ptr, s_len)) >= 0) /* seen for with-data, experimental TFO option, with-cookie case */ /* seen for with-data, proper TFO opt, with-cookie case */ { DEBUG(D_transport|D_v) - debug_printf("non-TFO mode connection attempt to %s, %lu data\n", + debug_printf(" TFO mode connection attempt to %s, %lu data\n", address, (unsigned long)fastopen_blob->len); - tcp_out_fastopen = fastopen_blob->len > 0 ? 2 : 1; + /*XXX also seen on successful TFO, sigh */ + tcp_out_fastopen = fastopen_blob->len > 0 ? TFO_ATTEMPTED_DATA : TFO_ATTEMPTED_NODATA; } - else if (errno == EINPROGRESS) /* expected if we had no cookie for peer */ + else switch (errno) + { + case EINPROGRESS: /* expected if we had no cookie for peer */ /* seen for no-data, proper TFO option, both cookie-request and with-cookie cases */ /* apparently no visibility of the diffference at this point */ /* seen for with-data, proper TFO opt, cookie-req */ /* 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 */ - DEBUG(D_transport|D_v) debug_printf("TFO mode sendto, %s data: EINPROGRESS\n", + DEBUG(D_transport|D_v) debug_printf(" TFO mode sendto, %s data: EINPROGRESS\n", + fastopen_blob->len > 0 ? "with" : "no"); + if (!fastopen_blob->data) + { + tcp_out_fastopen = TFO_ATTEMPTED_NODATA; /* we tried; unknown if useful yet */ + rc = 0; + } + else /* queue unsent data */ + rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0); + break; + + case EOPNOTSUPP: + DEBUG(D_transport) + debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n"); + goto legacy_connect; + + case EPIPE: + DEBUG(D_transport) + debug_printf("Tried TCP Fast Open but kernel too old to support it\n"); + goto legacy_connect; + } + +# elif defined(EXIM_TFO_FREEBSD) + /* Re: https://people.freebsd.org/~pkelsey/tfo-tools/tfo-client.c */ + + if (setsockopt(sock, IPPROTO_TCP, TCP_FASTOPEN, &on, sizeof(on)) < 0) + { + DEBUG(D_transport) + debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n"); + goto legacy_connect; + } + if ((rc = sendto(sock, fastopen_blob->data, fastopen_blob->len, 0, + s_ptr, s_len)) >= 0) + { + DEBUG(D_transport|D_v) + debug_printf(" TFO mode connection attempt to %s, %lu data\n", + address, (unsigned long)fastopen_blob->len); + tcp_out_fastopen = fastopen_blob->len > 0 ? TFO_ATTEMPTED_DATA : TFO_ATTEMPTED_NODATA; + } + +# elif defined(EXIM_TFO_CONNECTX) + /* MacOS */ + sa_endpoints_t ends = { + .sae_srcif = 0, .sae_srcaddr = NULL, .sae_srcaddrlen = 0, + .sae_dstaddr = s_ptr, .sae_dstaddrlen = s_len }; + struct iovec iov = { + .iov_base = fastopen_blob->data, .iov_len = fastopen_blob->len }; + size_t len; + + if ((rc = connectx(sock, &ends, SAE_ASSOCID_ANY, + CONNECT_DATA_IDEMPOTENT, &iov, 1, &len, NULL)) == 0) + { + DEBUG(D_transport|D_v) + debug_printf(" TFO mode connection attempt to %s, %lu data\n", + address, (unsigned long)fastopen_blob->len); + tcp_out_fastopen = fastopen_blob->len > 0 ? TFO_ATTEMPTED_DATA : TFO_ATTEMPTED_NODATA; + + if (len != fastopen_blob->len) + DEBUG(D_transport|D_v) + debug_printf(" only queued %lu data!\n", (unsigned long)len); + } + else if (errno == EINPROGRESS) + { + DEBUG(D_transport|D_v) debug_printf(" TFO mode connectx, %s data: EINPROGRESS\n", fastopen_blob->len > 0 ? "with" : "no"); if (!fastopen_blob->data) { - tcp_out_fastopen = 1; /* we tried; unknown if useful yet */ + tcp_out_fastopen = TFO_ATTEMPTED_NODATA; /* we tried; unknown if useful yet */ rc = 0; } - else + else /* assume that no data was queued; block in send */ rc = send(sock, fastopen_blob->data, fastopen_blob->len, 0); } - else if(errno == EOPNOTSUPP) - { - DEBUG(D_transport) - debug_printf("Tried TCP Fast Open but apparently not enabled by sysctl\n"); - goto legacy_connect; - } +# endif } else -#endif +#endif /*EXIM_SUPPORT_TFO*/ { +#if defined(EXIM_SUPPORT_TFO) && !defined(EXIM_TFO_CONNECTX) legacy_connect: +#endif + DEBUG(D_transport|D_v) if (fastopen_blob) - debug_printf("non-TFO mode connection attempt to %s, %lu data\n", + debug_printf(" non-TFO mode connection attempt to %s, %lu data\n", address, (unsigned long)fastopen_blob->len); if ((rc = connect(sock, s_ptr, s_len)) >= 0) if ( fastopen_blob && fastopen_blob->data && fastopen_blob->len @@ -302,13 +355,13 @@ legacy_connect: } save_errno = errno; -alarm(0); +ALARM_CLR(0); /* There is a testing facility for simulating a connection timeout, as I can't think of any other way of doing this. It converts a connection refused into a timeout if the timeout is set to 999999. */ -if (running_in_test_harness && save_errno == ECONNREFUSED && timeout == 999999) +if (f.running_in_test_harness && save_errno == ECONNREFUSED && timeout == 999999) { rc = -1; save_errno = EINTR; @@ -339,13 +392,13 @@ return -1; Arguments: type SOCK_DGRAM or SOCK_STREAM af AF_INET6 or AF_INET for the socket type - address the remote address, in text form + hostname host name, or ip address (as text) portlo,porthi the remote port range timeout a timeout connhost if not NULL, host_item to be filled in with connection details errstr pointer for allocated string on error fastopen_blob with SOCK_STREAM, if non-null, request TCP Fast Open. - Additionally, optional early-data to send + Additionally, optional idempotent early-data to send Return: socket fd, or -1 on failure (having allocated an error string) @@ -354,9 +407,8 @@ int ip_connectedsocket(int type, const uschar * hostname, int portlo, int porthi, int timeout, host_item * connhost, uschar ** errstr, const blob * fastopen_blob) { -int namelen, port; +int namelen; host_item shost; -host_item *h; int af = 0, fd, fd4 = -1, fd6 = -1; shost.next = NULL; @@ -400,7 +452,7 @@ else /* Try to connect to the server - test each IP till one works */ -for (h = &shost; h; h = h->next) +for (host_item * h = &shost; h; h = h->next) { fd = Ustrchr(h->address, ':') != 0 ? fd6 < 0 ? (fd6 = ip_socket(type, af = AF_INET6)) : fd6 @@ -412,7 +464,7 @@ for (h = &shost; h; h = h->next) goto bad; } - for(port = portlo; port <= porthi; port++) + for (int port = portlo; port <= porthi; port++) if (ip_connect(fd, af, h->address, port, timeout, fastopen_blob) == 0) { if (fd != fd6) close(fd6); @@ -437,7 +489,8 @@ bad: /*XXX TFO? */ int -ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo) +ip_tcpsocket(const uschar * hostport, uschar ** errstr, int tmo, + host_item * connhost) { int scan; uschar hostname[256]; @@ -456,7 +509,7 @@ if (scan != 3) } return ip_connectedsocket(SOCK_STREAM, hostname, portlow, porthigh, - tmo, NULL, errstr, NULL); + tmo, connhost, errstr, NULL); } int @@ -473,7 +526,7 @@ if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) callout_address = string_copy(path); server.sun_family = AF_UNIX; -Ustrncpy(server.sun_path, path, sizeof(server.sun_path)-1); +Ustrncpy(US server.sun_path, path, sizeof(server.sun_path)-1); server.sun_path[sizeof(server.sun_path)-1] = '\0'; if (connect(sock, (struct sockaddr *) &server, sizeof(server)) < 0) { @@ -486,11 +539,18 @@ if (connect(sock, (struct sockaddr *) &server, sizeof(server)) < 0) return sock; } +/* spec is either an absolute path (with a leading /), or +a host (name or IP) and port (whitespace-separated). +The port can be a range, dash-separated, or a single number. + +For a TCP socket, optionally fill in a host_item. +*/ int -ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo) +ip_streamsocket(const uschar * spec, uschar ** errstr, int tmo, + host_item * connhost) { return *spec == '/' - ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo); + ? ip_unixsocket(spec, errstr) : ip_tcpsocket(spec, errstr, tmo, connhost); } /************************************************* @@ -526,16 +586,15 @@ if (setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, /* Arguments: fd the file descriptor - timeout the timeout, seconds + timelimit the timeout endpoint, seconds-since-epoch Returns: TRUE => ready for i/o FALSE => timed out, or other error */ BOOL -fd_ready(int fd, int timeout) +fd_ready(int fd, time_t timelimit) { fd_set select_inset; -time_t start_recv = time(NULL); -int time_left = timeout; +int time_left = timelimit - time(NULL); int rc; if (time_left <= 0) @@ -569,8 +628,7 @@ do DEBUG(D_transport) debug_printf("EINTR while waiting for socket data\n"); /* Watch out, 'continue' jumps to the condition, not to the loops top */ - time_left = timeout - (time(NULL) - start_recv); - if (time_left > 0) continue; + if ((time_left = timelimit - time(NULL)) > 0) continue; } if (rc <= 0) @@ -594,24 +652,24 @@ Arguments: cctx the connection context (socket fd, possibly TLS context) buffer to read into bufsize the buffer size - timeout the timeout + timelimit the timeout endpoint, seconds-since-epoch Returns: > 0 => that much data read <= 0 on error or EOF; errno set - zero for EOF */ int -ip_recv(client_conn_ctx * cctx, uschar * buffer, int buffsize, int timeout) +ip_recv(client_conn_ctx * cctx, uschar * buffer, int buffsize, time_t timelimit) { int rc; -if (!fd_ready(cctx->sock, timeout)) +if (!fd_ready(cctx->sock, timelimit)) return -1; /* The socket is ready, read from it (via TLS if it's active). On EOF (i.e. close down of the connection), set errno to zero; otherwise leave it alone. */ -#ifdef SUPPORT_TLS +#ifndef DISABLE_TLS if (cctx->tls_ctx) /* client TLS */ rc = tls_read(cctx->tls_ctx, buffer, buffsize); else if (tls_in.active.sock == cctx->sock) /* server TLS */ @@ -795,8 +853,7 @@ return FALSE; void dscp_list_to_stream(FILE *stream) { -int i; -for (i=0; i < dscp_table_size; ++i) +for (int i = 0; i < dscp_table_size; ++i) fprintf(stream, "%s\n", dscp_table[i].name); }