X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/18481de384caecff421f23f715be916403f5d0ee..60d10ce7e68a5f2cf771a5c079521c8e4f18d157:/src/src/smtp_in.c diff --git a/src/src/smtp_in.c b/src/src/smtp_in.c index b00537eb5..9484105d6 100644 --- a/src/src/smtp_in.c +++ b/src/src/smtp_in.c @@ -73,7 +73,6 @@ enum { ETRN_CMD, /* This by analogy with TURN from the RFC */ STARTTLS_CMD, /* Required by the STARTTLS RFC */ TLS_AUTH_CMD, /* auto-command at start of SSL */ - BDAT_CMD, /* Implied by RFC3030 "After all MAIL and..." */ /* This is a dummy to identify the non-sync commands when pipelining */ @@ -83,6 +82,15 @@ enum { MAIL_CMD, RCPT_CMD, RSET_CMD, + /* RFC3030 section 2: "After all MAIL and RCPT responses are collected and + processed the message is sent using a series of BDAT commands" + implies that BDAT should be synchronized. However, we see Google, at least, + sending MAIL,RCPT,BDAT-LAST in a single packet, clearly not waiting for + processing of the RPCT response(s). We shall do the same, and not require + synch for BDAT. */ + + BDAT_CMD, + /* This is a dummy to identify the non-sync commands when not pipelining */ NON_SYNC_CMD_NON_PIPELINING, @@ -291,6 +299,13 @@ static int smtp_had_eof; static int smtp_had_error; +/* forward declarations */ +int bdat_ungetc(int ch); +static int smtp_read_command(BOOL check_sync); +static int synprot_error(int type, int code, uschar *data, uschar *errmess); +static void smtp_quit_handler(uschar **, uschar **); +static void smtp_rset_handler(void); + /************************************************* * SMTP version of getc() * *************************************************/ @@ -310,6 +325,7 @@ smtp_getc(void) if (smtp_inptr >= smtp_inend) { int rc, save_errno; + if (!smtp_out) return EOF; fflush(smtp_out); if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout); rc = read(fileno(smtp_in), smtp_inbuffer, in_buffer_size); @@ -337,6 +353,145 @@ if (smtp_inptr >= smtp_inend) return *smtp_inptr++; } +void +smtp_get_cache(void) +{ +#ifndef DISABLE_DKIM +int n = smtp_inend - smtp_inptr; +if (n > 0) + dkim_exim_verify_feed(smtp_inptr, n); +#endif +} + + +/* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the +previous BDAT chunk and getting new ones when we run out. Uses the +underlying smtp_getc or tls_getc both for that and for getting the +(buffered) data byte. EOD signals (an expected) no further data. +ERR signals a protocol error, and EOF a closed input stream. + +Called from read_bdat_smtp() in receive.c for the message body, but also +by the headers read loop in receive_msg(); manipulates chunking_state +to handle the BDAT command/response. +Placed here due to the correlation with the above smtp_getc(), which it wraps, +and also by the need to do smtp command/response handling. + +Arguments: none +Returns: the next character or ERR, EOD or EOF +*/ + +int +bdat_getc(void) +{ +uschar * user_msg = NULL; +uschar * log_msg; + +for(;;) + { + if (chunking_data_left-- > 0) + return lwr_receive_getc(); + + receive_getc = lwr_receive_getc; + receive_ungetc = lwr_receive_ungetc; + + /* If not the last, ack the received chunk. The last response is delayed + until after the data ACL decides on it */ + + if (chunking_state == CHUNKING_LAST) + { +#ifndef DISABLE_DKIM + dkim_exim_verify_feed(NULL, 0); /* notify EOD */ +#endif + return EOD; + } + + chunking_state = CHUNKING_OFFERED; + smtp_printf("250 %u byte chunk received\r\n", chunking_datasize); + + /* Expect another BDAT cmd from input. RFC 3030 says nothing about + QUIT, RSET or NOOP but handling them seems obvious */ + +next_cmd: + switch(smtp_read_command(TRUE)) + { + default: + (void) synprot_error(L_smtp_protocol_error, 503, NULL, + US"only BDAT permissible after non-LAST BDAT"); + + repeat_until_rset: + switch(smtp_read_command(TRUE)) + { + case QUIT_CMD: smtp_quit_handler(&user_msg, &log_msg); /*FALLTHROUGH */ + case EOF_CMD: return EOF; + case RSET_CMD: smtp_rset_handler(); return ERR; + default: if (synprot_error(L_smtp_protocol_error, 503, NULL, + US"only RSET accepted now") > 0) + return EOF; + goto repeat_until_rset; + } + + case QUIT_CMD: + smtp_quit_handler(&user_msg, &log_msg); + /*FALLTHROUGH*/ + case EOF_CMD: + return EOF; + + case RSET_CMD: + smtp_rset_handler(); + return ERR; + + case NOOP_CMD: + HAD(SCH_NOOP); + smtp_printf("250 OK\r\n"); + goto next_cmd; + + case BDAT_CMD: + { + int n; + + if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) + { + (void) synprot_error(L_smtp_protocol_error, 501, NULL, + US"missing size for BDAT command"); + return ERR; + } + chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 + ? CHUNKING_LAST : CHUNKING_ACTIVE; + chunking_data_left = chunking_datasize; + + if (chunking_datasize == 0) + if (chunking_state == CHUNKING_LAST) + return EOD; + else + { + (void) synprot_error(L_smtp_protocol_error, 504, NULL, + US"zero size for BDAT command"); + goto repeat_until_rset; + } + + receive_getc = bdat_getc; + receive_ungetc = bdat_ungetc; + break; /* to top of main loop */ + } + } + } +} + +static void +bdat_flush_data(void) +{ +while (chunking_data_left-- > 0) + if (lwr_receive_getc() < 0) + break; + +receive_getc = lwr_receive_getc; +receive_ungetc = lwr_receive_ungetc; + +if (chunking_state != CHUNKING_LAST) + chunking_state = CHUNKING_OFFERED; +} + + /************************************************* @@ -355,11 +510,18 @@ Returns: the character int smtp_ungetc(int ch) { -*(--smtp_inptr) = ch; +*--smtp_inptr = ch; return ch; } +int +bdat_ungetc(int ch) +{ +chunking_data_left++; +return lwr_receive_ungetc(ch); +} + /************************************************* @@ -1182,26 +1344,23 @@ if (smtp_in == NULL || smtp_batched_input) return; receive_swallow_smtp(); smtp_printf("421 %s\r\n", message); -for (;;) +for (;;) switch(smtp_read_command(FALSE)) { - switch(smtp_read_command(FALSE)) - { - case EOF_CMD: - return; + case EOF_CMD: + return; - case QUIT_CMD: - smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); - mac_smtp_fflush(); - return; + case QUIT_CMD: + smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); + mac_smtp_fflush(); + return; - case RSET_CMD: - smtp_printf("250 Reset OK\r\n"); - break; + case RSET_CMD: + smtp_printf("250 Reset OK\r\n"); + break; - default: - smtp_printf("421 %s\r\n", message); - break; - } + default: + smtp_printf("421 %s\r\n", message); + break; } } @@ -1527,7 +1686,6 @@ authenticated_sender = NULL; bmi_run = 0; bmi_verdicts = NULL; #endif -chunking_state = CHUNKING_NOT_OFFERED; #ifndef DISABLE_DKIM dkim_signers = NULL; dkim_disable_verify = FALSE; @@ -1889,10 +2047,10 @@ acl_var_c = NULL; /* Allow for trailing 0 in the command and data buffers. */ -smtp_cmd_buffer = (uschar *)malloc(2*smtp_cmd_buffer_size + 2); -if (smtp_cmd_buffer == NULL) +if (!(smtp_cmd_buffer = US malloc(2*smtp_cmd_buffer_size + 2))) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP command buffer"); + smtp_cmd_buffer[0] = 0; smtp_data_buffer = smtp_cmd_buffer + smtp_cmd_buffer_size + 1; @@ -1901,7 +2059,7 @@ command line by a trusted caller. */ if (smtp_batched_input) { - if (received_protocol == NULL) received_protocol = US"local-bsmtp"; + if (!received_protocol) received_protocol = US"local-bsmtp"; } /* For non-batched SMTP input, the protocol setting is forced here. It will be @@ -1914,10 +2072,11 @@ else /* Set up the buffer for inputting using direct read() calls, and arrange to call the local functions instead of the standard C ones. */ -smtp_inbuffer = (uschar *)malloc(in_buffer_size); -if (smtp_inbuffer == NULL) +if (!(smtp_inbuffer = (uschar *)malloc(in_buffer_size))) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer"); + receive_getc = smtp_getc; +receive_get_cache = smtp_get_cache; receive_ungetc = smtp_ungetc; receive_feof = smtp_feof; receive_ferror = smtp_ferror; @@ -2800,8 +2959,9 @@ if (lognl != NULL) *lognl = 0; always a 5xx one - see comments at the start of this function. If the original rc was FAIL_DROP we drop the connection and yield 2. */ -if (rc == FAIL) smtp_respond(smtp_code, codelen, TRUE, (user_msg == NULL)? - US"Administrative prohibition" : user_msg); +if (rc == FAIL) + smtp_respond(smtp_code, codelen, TRUE, + user_msg ? user_msg : US"Administrative prohibition"); /* Send temporary failure response to the command. Don't give any details, unless acl_temp_details is set. This is TRUE for a callout defer, a "defer" @@ -2812,21 +2972,19 @@ interactions between temp_details and return_error_details. One day it should be re-implemented in a tidier fashion. */ else - { - if (acl_temp_details && user_msg != NULL) + if (acl_temp_details && user_msg) { - if (smtp_return_error_details && - sender_verified_failed != NULL && - sender_verified_failed->message != NULL) - { + if ( smtp_return_error_details + && sender_verified_failed + && sender_verified_failed->message + ) smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message); - } + smtp_respond(smtp_code, codelen, TRUE, user_msg); } else smtp_respond(smtp_code, codelen, TRUE, US"Temporary local problem - please try later"); - } /* Log the incident to the logs that are specified by log_reject_target (default main, reject). This can be empty to suppress logging of rejections. If @@ -2910,12 +3068,11 @@ smtp_exit_function_called = TRUE; /* Call the not-QUIT ACL, if there is one, unless no reason is given. */ -if (acl_smtp_notquit != NULL && reason != NULL) +if (acl_smtp_notquit && reason) { smtp_notquit_reason = reason; - rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg, - &log_msg); - if (rc == ERROR) + if ((rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg, + &log_msg)) == ERROR) log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s", log_msg); } @@ -2925,9 +3082,11 @@ responses are all internal, they should always fit in the buffer, but code a warning, just in case. Note that string_vformat() still leaves a complete string, even if it is incomplete. */ -if (code != NULL && defaultrespond != NULL) +if (code && defaultrespond) { - if (user_msg == NULL) + if (user_msg) + smtp_respond(code, 3, TRUE, user_msg); + else { uschar buffer[128]; va_list ap; @@ -2937,8 +3096,6 @@ if (code != NULL && defaultrespond != NULL) smtp_printf("%s %s\r\n", code, buffer); va_end(ap); } - else - smtp_respond(code, 3, TRUE, user_msg); mac_smtp_fflush(); } } @@ -3239,6 +3396,43 @@ return 0; +static void +smtp_quit_handler(uschar ** user_msgp, uschar ** log_msgp) +{ +HAD(SCH_QUIT); +incomplete_transaction_log(US"QUIT"); +if (acl_smtp_quit) + { + int rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, user_msgp, log_msgp); + if (rc == ERROR) + log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", + *log_msgp); + } +if (*user_msgp) + smtp_respond(US"221", 3, TRUE, *user_msgp); +else + smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); + +#ifdef SUPPORT_TLS +tls_close(TRUE, TRUE); +#endif + +log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", + smtp_get_connection_info()); +} + + +static void +smtp_rset_handler(void) +{ +HAD(SCH_RSET); +incomplete_transaction_log(US"RSET"); +smtp_printf("250 Reset OK\r\n"); +cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE; +} + + + /************************************************* * Initialize for SMTP incoming message * *************************************************/ @@ -3285,6 +3479,8 @@ for the host). Note: we do NOT reset AUTH at this point. */ smtp_reset(reset_point); message_ended = END_NOTSTARTED; +chunking_state = chunking_offered ? CHUNKING_OFFERED : CHUNKING_NOT_OFFERED; + cmd_list[CMD_LIST_RSET].is_mail_cmd = TRUE; cmd_list[CMD_LIST_HELO].is_mail_cmd = TRUE; cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE; @@ -3775,6 +3971,7 @@ while (done <= 0) { s = string_catn(s, &size, &ptr, smtp_code, 3); s = string_catn(s, &size, &ptr, US"-CHUNKING\r\n", 11); + chunking_offered = TRUE; chunking_state = CHUNKING_OFFERED; } @@ -4546,12 +4743,18 @@ while (done <= 0) if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) { - done = synprot_error(L_smtp_protocol_error, 503, NULL, + done = synprot_error(L_smtp_protocol_error, 501, NULL, US"missing size for BDAT command"); break; } chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 ? CHUNKING_LAST : CHUNKING_ACTIVE; + chunking_data_left = chunking_datasize; + + lwr_receive_getc = receive_getc; + lwr_receive_ungetc = receive_ungetc; + receive_getc = bdat_getc; + receive_ungetc = bdat_ungetc; DEBUG(D_any) debug_printf("chunking state %d\n", (int)chunking_state); @@ -4583,6 +4786,9 @@ while (done <= 0) smtp_connection_had[smtp_ch_index-1] == SCH_DATA ? US"valid RCPT command must precede DATA" : US"valid RCPT command must precede BDAT"); + + if (chunking_state > CHUNKING_OFFERED) + bdat_flush_data(); break; } @@ -4594,45 +4800,45 @@ while (done <= 0) break; } - /* No go-ahead output for BDAT */ - - if (smtp_connection_had[smtp_ch_index-1] == SCH_BDAT) - { + if (chunking_state > CHUNKING_OFFERED) + { /* No predata ACL or go-ahead output for BDAT */ rc = OK; - break; } - - /* If there is an ACL, re-check the synchronization afterwards, since the - ACL may have delayed. To handle cutthrough delivery enforce a dummy call - to get the DATA command sent. */ - - if (acl_smtp_predata == NULL && cutthrough.fd < 0) - rc = OK; else { - uschar * acl= acl_smtp_predata ? acl_smtp_predata : US"accept"; - enable_dollar_recipients = TRUE; - rc = acl_check(ACL_WHERE_PREDATA, NULL, acl, &user_msg, - &log_msg); - enable_dollar_recipients = FALSE; - if (rc == OK && !check_sync()) goto SYNC_FAILURE; - } + /* If there is an ACL, re-check the synchronization afterwards, since the + ACL may have delayed. To handle cutthrough delivery enforce a dummy call + to get the DATA command sent. */ - if (rc == OK) - { - uschar * code; - code = US"354"; - if (user_msg == NULL) - smtp_printf("%s Enter message, ending with \".\" on a line by itself\r\n", code); - else smtp_user_msg(code, user_msg); - done = 3; - message_ended = END_NOTENDED; /* Indicate in middle of data */ + if (acl_smtp_predata == NULL && cutthrough.fd < 0) + rc = OK; + else + { + uschar * acl = acl_smtp_predata ? acl_smtp_predata : US"accept"; + enable_dollar_recipients = TRUE; + rc = acl_check(ACL_WHERE_PREDATA, NULL, acl, &user_msg, + &log_msg); + enable_dollar_recipients = FALSE; + if (rc == OK && !check_sync()) + goto SYNC_FAILURE; + + if (rc != OK) + { /* Either the ACL failed the address, or it was deferred. */ + done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg); + break; + } + } + + if (user_msg) + smtp_user_msg(US"354", user_msg); + else + smtp_printf( + "354 Enter message, ending with \".\" on a line by itself\r\n"); } - /* Either the ACL failed the address, or it was deferred. */ + done = 3; + message_ended = END_NOTENDED; /* Indicate in middle of data */ - else - done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg); break; @@ -4818,45 +5024,39 @@ while (done <= 0) set, but we must still reject all incoming commands. */ DEBUG(D_tls) debug_printf("TLS failed to start\n"); - while (done <= 0) + while (done <= 0) switch(smtp_read_command(FALSE)) { - switch(smtp_read_command(FALSE)) - { - case EOF_CMD: - log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF", - smtp_get_connection_info()); - smtp_notquit_exit(US"tls-failed", NULL, NULL); - done = 2; - break; - - /* It is perhaps arguable as to which exit ACL should be called here, - but as it is probably a situation that almost never arises, it - probably doesn't matter. We choose to call the real QUIT ACL, which in - some sense is perhaps "right". */ + case EOF_CMD: + log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF", + smtp_get_connection_info()); + smtp_notquit_exit(US"tls-failed", NULL, NULL); + done = 2; + break; - case QUIT_CMD: - user_msg = NULL; - if (acl_smtp_quit != NULL) - { - rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, &user_msg, - &log_msg); - if (rc == ERROR) - log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", - log_msg); - } - if (user_msg == NULL) - smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); - else - smtp_respond(US"221", 3, TRUE, user_msg); - log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", - smtp_get_connection_info()); - done = 2; - break; + /* It is perhaps arguable as to which exit ACL should be called here, + but as it is probably a situation that almost never arises, it + probably doesn't matter. We choose to call the real QUIT ACL, which in + some sense is perhaps "right". */ + + case QUIT_CMD: + user_msg = NULL; + if ( acl_smtp_quit + && ((rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, &user_msg, + &log_msg)) == ERROR)) + log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", + log_msg); + if (user_msg) + smtp_respond(US"221", 3, TRUE, user_msg); + else + smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); + log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", + smtp_get_connection_info()); + done = 2; + break; - default: - smtp_printf("554 Security failure\r\n"); - break; - } + default: + smtp_printf("554 Security failure\r\n"); + break; } tls_close(TRUE, TRUE); break; @@ -4868,37 +5068,15 @@ while (done <= 0) message. */ case QUIT_CMD: - HAD(SCH_QUIT); - incomplete_transaction_log(US"QUIT"); - if (acl_smtp_quit != NULL) - { - rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, &user_msg, &log_msg); - if (rc == ERROR) - log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", - log_msg); - } - if (user_msg == NULL) - smtp_printf("221 %s closing connection\r\n", smtp_active_hostname); - else - smtp_respond(US"221", 3, TRUE, user_msg); - - #ifdef SUPPORT_TLS - tls_close(TRUE, TRUE); - #endif - + smtp_quit_handler(&user_msg, &log_msg); done = 2; - log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", - smtp_get_connection_info()); break; case RSET_CMD: - HAD(SCH_RSET); - incomplete_transaction_log(US"RSET"); + smtp_rset_handler(); smtp_reset(reset_point); toomany = FALSE; - smtp_printf("250 Reset OK\r\n"); - cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE; break; @@ -4925,7 +5103,7 @@ while (done <= 0) verify_check_host(&tls_advertise_hosts) != FAIL) Ustrcat(buffer, " STARTTLS"); #endif - Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA"); + Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA BDAT"); Ustrcat(buffer, " NOOP QUIT RSET HELP"); if (acl_smtp_etrn != NULL) Ustrcat(buffer, " ETRN"); if (acl_smtp_expn != NULL) Ustrcat(buffer, " EXPN");