X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/e498ab40197936833f696439e78c5cb08e5180cb..f9d4bb1a2ae19edfcde680bebfeb8712e6f2a42a:/src/src/spool_in.c diff --git a/src/src/spool_in.c b/src/src/spool_in.c index 7eb42907c..0b3490b22 100644 --- a/src/src/spool_in.c +++ b/src/src/spool_in.c @@ -2,7 +2,7 @@ * Exim - an Internet mail transport agent * *************************************************/ -/* Copyright (c) University of Cambridge 1995 - 2016 */ +/* Copyright (c) University of Cambridge 1995 - 2018 */ /* See the file NOTICE for conditions of use and distribution. */ /* Functions for reading spool files. When compiling for a utility (eximon), @@ -25,6 +25,8 @@ fact it won't be written to. Just in case there's a major disaster (e.g. overwriting some other file descriptor with the value of this one), open it with append. +As called by deliver_message() (at least) we are operating as root. + Argument: the id of the message Returns: fd if file successfully opened and locked, else -1 @@ -51,11 +53,23 @@ for (i = 0; i < 2; i++) uschar * fname; int save_errno; - message_subdir[0] = split_spool_directory == i == 0 ? id[5] : 0; + message_subdir[0] = split_spool_directory == i ? '\0' : id[5]; fname = spool_fname(US"input", message_subdir, id, US"-D"); DEBUG(D_deliver) debug_printf("Trying spool file %s\n", fname); - if ((fd = Uopen(fname, O_RDWR | O_APPEND, 0)) >= 0) + /* We protect against symlink attacks both in not propagating the + * file-descriptor to other processes as we exec, and also ensuring that we + * don't even open symlinks. + * No -D file inside the spool area should be a symlink. + */ + if ((fd = Uopen(fname, +#ifdef O_CLOEXEC + O_CLOEXEC | +#endif +#ifdef O_NOFOLLOW + O_NOFOLLOW | +#endif + O_RDWR | O_APPEND, 0)) >= 0) break; save_errno = errno; if (errno == ENOENT) @@ -63,8 +77,8 @@ for (i = 0; i < 2; i++) if (i == 0) continue; if (!queue_running) log_write(0, LOG_MAIN, "Spool%s%s file %s-D not found", - *queue_name ? " Q=" : "", - *queue_name ? queue_name : "", + *queue_name ? US" Q=" : US"", + *queue_name ? queue_name : US"", id); } else @@ -81,8 +95,9 @@ an open file descriptor (at least, I think that's the Cygwin story). On real Unix systems it doesn't make any difference as long as Exim is consistent in what it locks. */ -(void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | - FD_CLOEXEC); +#ifndef O_CLOEXEC +(void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC); +#endif lock_data.l_type = F_WRLCK; lock_data.l_whence = SEEK_SET; @@ -199,47 +214,13 @@ return TRUE; -/************************************************* -* Read spool header file * -*************************************************/ - -/* This function reads a spool header file and places the data into the -appropriate global variables. The header portion is always read, but header -structures are built only if read_headers is set true. It isn't, for example, -while generating -bp output. - -It may be possible for blocks of nulls (binary zeroes) to get written on the -end of a file if there is a system crash during writing. It was observed on an -earlier version of Exim that omitted to fsync() the files - this is thought to -have been the cause of that incident, but in any case, this code must be robust -against such an event, and if such a file is encountered, it must be treated as -malformed. - -Arguments: - name name of the header file, including the -H - read_headers TRUE if in-store header structures are to be built - subdir_set TRUE is message_subdir is already set - -Returns: spool_read_OK success - spool_read_notopen open failed - spool_read_enverror error in the envelope portion - spool_read_hdrdrror error in the header portion -*/ - -int -spool_read_header(uschar *name, BOOL read_headers, BOOL subdir_set) -{ -FILE *f = NULL; -int n; -int rcount = 0; -long int uid, gid; -BOOL inheader = FALSE; -uschar *p; - /* Reset all the global variables to their default values. However, there is one exception. DO NOT change the default value of dont_deliver, because it may be forced by an external setting. */ +void +spool_clear_header_globals(void) +{ acl_var_c = acl_var_m = NULL; authenticated_id = NULL; authenticated_sender = NULL; @@ -258,7 +239,9 @@ host_lookup_failed = FALSE; interface_address = NULL; interface_port = 0; local_error_message = FALSE; +#ifdef HAVE_LOCAL_SCAN local_scan_data = NULL; +#endif max_received_linelength = 0; message_linecount = 0; received_protocol = NULL; @@ -275,6 +258,9 @@ sender_ident = NULL; sender_local = FALSE; sender_set_untrusted = FALSE; smtp_active_hostname = primary_hostname; +#ifndef COMPILE_UTILITY +spool_file_wireformat = FALSE; +#endif tree_nonrecipients = NULL; #ifdef EXPERIMENTAL_BRIGHTMAIL @@ -285,12 +271,12 @@ bmi_verdicts = NULL; #ifndef DISABLE_DKIM dkim_signers = NULL; dkim_disable_verify = FALSE; -dkim_collect_input = FALSE; +dkim_collect_input = 0; #endif #ifdef SUPPORT_TLS tls_in.certificate_verified = FALSE; -# ifdef EXPERIMENTAL_DANE +# ifdef SUPPORT_DANE tls_in.dane_verified = FALSE; # endif tls_in.cipher = NULL; @@ -301,6 +287,9 @@ tls_free_cert(&tls_in.peercert); tls_in.peerdn = NULL; tls_in.sni = NULL; tls_in.ocsp = OCSP_NOT_REQ; +# if defined(EXPERIMENTAL_REQUIRETLS) && !defined(COMPILE_UTILITY) +tls_requiretls = 0; +# endif #endif #ifdef WITH_CONTENT_SCAN @@ -316,6 +305,53 @@ message_utf8_downconvert = 0; dsn_ret = 0; dsn_envid = NULL; +} + + +/************************************************* +* Read spool header file * +*************************************************/ + +/* This function reads a spool header file and places the data into the +appropriate global variables. The header portion is always read, but header +structures are built only if read_headers is set true. It isn't, for example, +while generating -bp output. + +It may be possible for blocks of nulls (binary zeroes) to get written on the +end of a file if there is a system crash during writing. It was observed on an +earlier version of Exim that omitted to fsync() the files - this is thought to +have been the cause of that incident, but in any case, this code must be robust +against such an event, and if such a file is encountered, it must be treated as +malformed. + +As called from deliver_message() (at least) we are running as root. + +Arguments: + name name of the header file, including the -H + read_headers TRUE if in-store header structures are to be built + subdir_set TRUE is message_subdir is already set + +Returns: spool_read_OK success + spool_read_notopen open failed + spool_read_enverror error in the envelope portion + spool_read_hdrerror error in the header portion +*/ + +int +spool_read_header(uschar *name, BOOL read_headers, BOOL subdir_set) +{ +FILE *f = NULL; +int n; +int rcount = 0; +long int uid, gid; +BOOL inheader = FALSE; +uschar *p; + +/* Reset all the global variables to their default values. However, there is +one exception. DO NOT change the default value of dont_deliver, because it may +be forced by an external setting. */ + +spool_clear_header_globals(); /* Generate the full name and open the file. If message_subdir is already set, just look in the given directory. Otherwise, look in both the split @@ -385,10 +421,11 @@ sender_address[n-3] = 0; /* time */ if (Ufgets(big_buffer, big_buffer_size, f) == NULL) goto SPOOL_READ_ERROR; -if (sscanf(CS big_buffer, "%d %d", &received_time, &warning_count) != 2) +if (sscanf(CS big_buffer, TIME_T_FMT " %d", &received_time.tv_sec, &warning_count) != 2) goto SPOOL_FORMAT_ERROR; +received_time.tv_usec = 0; -message_age = time(NULL) - received_time; +message_age = time(NULL) - received_time.tv_sec; #ifndef COMPILE_UTILITY DEBUG(D_deliver) debug_printf("user=%s uid=%ld gid=%ld sender=%s\n", @@ -446,8 +483,8 @@ for (;;) tree_node *node; endptr = Ustrchr(big_buffer + 6, ' '); if (endptr == NULL) goto SPOOL_FORMAT_ERROR; - name = string_sprintf("%c%.*s", big_buffer[4], endptr - big_buffer - 6, - big_buffer + 6); + name = string_sprintf("%c%.*s", big_buffer[4], + (int)(endptr - big_buffer - 6), big_buffer + 6); if (sscanf(CS endptr, " %d", &count) != 1) goto SPOOL_FORMAT_ERROR; node = acl_var_create(name); node->data.ptr = store_get(count + 1); @@ -476,21 +513,24 @@ for (;;) else if (Ustrncmp(p, "cl ", 3) == 0) { - int index, count; - uschar name[20]; /* Need plenty of space for %d format */ - tree_node *node; - if ( sscanf(CS big_buffer + 5, "%d %d", &index, &count) != 2 + unsigned index, count; + uschar name[20]; /* Need plenty of space for %u format */ + tree_node * node; + if ( sscanf(CS big_buffer + 5, "%u %u", &index, &count) != 2 || index >= 20 + || count > 16384 /* arbitrary limit on variable size */ ) goto SPOOL_FORMAT_ERROR; if (index < 10) - (void) string_format(name, sizeof(name), "%c%d", 'c', index); + (void) string_format(name, sizeof(name), "%c%u", 'c', index); else - (void) string_format(name, sizeof(name), "%c%d", 'm', index - 10); + (void) string_format(name, sizeof(name), "%c%u", 'm', index - 10); node = acl_var_create(name); node->data.ptr = store_get(count + 1); + /* We sanity-checked the count, so disable the Coverity error */ + /* coverity[tainted_data] */ if (fread(node->data.ptr, 1, count+1, f) < count) goto SPOOL_READ_ERROR; - ((uschar*)node->data.ptr)[count] = 0; + (US node->data.ptr)[count] = '\0'; } break; @@ -558,11 +598,14 @@ for (;;) break; case 'l': - if (Ustrcmp(p, "ocal") == 0) sender_local = TRUE; + if (Ustrcmp(p, "ocal") == 0) + sender_local = TRUE; else if (Ustrcmp(big_buffer, "-localerror") == 0) local_error_message = TRUE; +#ifdef HAVE_LOCAL_SCAN else if (Ustrncmp(p, "ocal_scan ", 10) == 0) local_scan_data = string_copy(big_buffer + 12); +#endif break; case 'm': @@ -578,6 +621,12 @@ for (;;) case 'r': if (Ustrncmp(p, "eceived_protocol", 16) == 0) received_protocol = string_copy(big_buffer + 19); + else if (Ustrncmp(p, "eceived_time_usec", 17) == 0) + { + unsigned usec; + if (sscanf(CS big_buffer + 21, "%u", &usec) == 1) + received_time.tv_usec = usec; + } break; case 's': @@ -591,6 +640,10 @@ for (;;) else if (Ustrncmp(p, "pam_score_int ", 14) == 0) spam_score_int = string_copy(big_buffer + 16); #endif +#ifndef COMPILE_UTILITY + else if (Ustrncmp(p, "pool_file_wireformat", 20) == 0) + spool_file_wireformat = TRUE; +#endif #if defined(SUPPORT_I18N) && !defined(COMPILE_UTILITY) else if (Ustrncmp(p, "mtputf8", 7) == 0) message_smtputf8 = TRUE; @@ -599,22 +652,30 @@ for (;;) #ifdef SUPPORT_TLS case 't': - if (Ustrncmp(p, "ls_certificate_verified", 23) == 0) - tls_in.certificate_verified = TRUE; - else if (Ustrncmp(p, "ls_cipher", 9) == 0) - tls_in.cipher = string_copy(big_buffer + 12); + if (Ustrncmp(p, "ls_", 3) == 0) + { + uschar * q = p + 3; + if (Ustrncmp(q, "certificate_verified", 20) == 0) + tls_in.certificate_verified = TRUE; + else if (Ustrncmp(q, "cipher", 6) == 0) + tls_in.cipher = string_copy(big_buffer + 12); # ifndef COMPILE_UTILITY /* tls support fns not built in */ - else if (Ustrncmp(p, "ls_ourcert", 10) == 0) - (void) tls_import_cert(big_buffer + 13, &tls_in.ourcert); - else if (Ustrncmp(p, "ls_peercert", 11) == 0) - (void) tls_import_cert(big_buffer + 14, &tls_in.peercert); + else if (Ustrncmp(q, "ourcert", 7) == 0) + (void) tls_import_cert(big_buffer + 13, &tls_in.ourcert); + else if (Ustrncmp(q, "peercert", 8) == 0) + (void) tls_import_cert(big_buffer + 14, &tls_in.peercert); +# endif + else if (Ustrncmp(q, "peerdn", 6) == 0) + tls_in.peerdn = string_unprinting(string_copy(big_buffer + 12)); + else if (Ustrncmp(q, "sni", 3) == 0) + tls_in.sni = string_unprinting(string_copy(big_buffer + 9)); + else if (Ustrncmp(q, "ocsp", 4) == 0) + tls_in.ocsp = big_buffer[10] - '0'; +# if defined(EXPERIMENTAL_REQUIRETLS) && !defined(COMPILE_UTILITY) + else if (Ustrncmp(q, "requiretls", 10) == 0) + tls_requiretls = strtol(CS big_buffer+16, NULL, 0); # endif - else if (Ustrncmp(p, "ls_peerdn", 9) == 0) - tls_in.peerdn = string_unprinting(string_copy(big_buffer + 12)); - else if (Ustrncmp(p, "ls_sni", 6) == 0) - tls_in.sni = string_unprinting(string_copy(big_buffer + 9)); - else if (Ustrncmp(p, "ls_ocsp", 7) == 0) - tls_in.ocsp = big_buffer[10] - '0'; + } break; #endif @@ -660,10 +721,12 @@ DEBUG(D_deliver) #endif /* COMPILE_UTILITY */ /* After reading the tree, the next line has not yet been read into the -buffer. It contains the count of recipients which follow on separate lines. */ +buffer. It contains the count of recipients which follow on separate lines. +Apply an arbitrary sanity check.*/ if (Ufgets(big_buffer, big_buffer_size, f) == NULL) goto SPOOL_READ_ERROR; -if (sscanf(CS big_buffer, "%d", &rcount) != 1) goto SPOOL_FORMAT_ERROR; +if (sscanf(CS big_buffer, "%d", &rcount) != 1 || rcount > 16384) + goto SPOOL_FORMAT_ERROR; #ifndef COMPILE_UTILITY DEBUG(D_deliver) debug_printf("recipients_count=%d\n", rcount); @@ -672,6 +735,10 @@ DEBUG(D_deliver) debug_printf("recipients_count=%d\n", rcount); recipients_list_max = rcount; recipients_list = store_get(rcount * sizeof(recipient_item)); +/* We sanitised the count and know we have enough memory, so disable +the Coverity error on recipients_count */ +/* coverity[tainted_data] */ + for (recipients_count = 0; recipients_count < rcount; recipients_count++) { int nn;