X-Git-Url: https://vcs.fsf.org/?a=blobdiff_plain;f=src%2Fsrc%2Frda.c;h=aed8abc246b54b5e1a764f0e13171c827f958542;hb=a63442492d25b3ab12d0bce2a8b879e32855aa72;hp=201e82d8b8a0bee54fd1344f9d622f1c0eba9d18;hpb=0d2e392e281e96d9f9f2f3dd438affe3f2563c57;p=exim.git diff --git a/src/src/rda.c b/src/src/rda.c index 201e82d8b..aed8abc24 100644 --- a/src/src/rda.c +++ b/src/src/rda.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. */ /* This module contains code for extracting addresses from a forwarding list @@ -41,7 +42,7 @@ Returns: FILTER_EXIM if it starts with "# Exim filter" static BOOL match_tag(const uschar *s, const uschar *tag) { -for (; *tag != 0; s++, tag++) +for (; *tag; s++, tag++) if (*tag == ' ') { while (*s == ' ' || *s == '\t') s++; @@ -59,10 +60,10 @@ tags for other types of filter. */ int rda_is_filter(const uschar *s) { -while (isspace(*s)) s++; /* Skips initial blank lines */ -if (match_tag(s, CUS"# exim filter")) return FILTER_EXIM; - else if (match_tag(s, CUS"# sieve filter")) return FILTER_SIEVE; - else return FILTER_FORWARD; +Uskip_whitespace(&s); /* Skips initial blank lines */ +if (match_tag(s, CUS"# exim filter")) return FILTER_EXIM; +else if (match_tag(s, CUS"# sieve filter")) return FILTER_SIEVE; +else return FILTER_FORWARD; } @@ -175,6 +176,17 @@ BOOL uid_ok = !rdata->check_owner; BOOL gid_ok = !rdata->check_group; struct stat statbuf; +/* Reading a file is a form of expansion; we wish to deny attackers the +capability to specify the file name. */ + +if (is_tainted(filename)) + { + *error = string_sprintf("Tainted name '%s' for file read not permitted\n", + filename); + *yield = FF_ERROR; + return NULL; + } + /* Attempt to open the file. If it appears not to exist, check up on the containing directory by statting it. If the directory does not exist, we treat this situation as an error (which will cause delivery to defer); otherwise we @@ -195,20 +207,20 @@ if (!(fwd = Ufopen(filename, "rb"))) switch(errno) return NULL; case ENOTDIR: /* Something on the path isn't a directory */ - if ((options & RDO_ENOTDIR) == 0) goto DEFAULT_ERROR; + if (!(options & RDO_ENOTDIR)) goto DEFAULT_ERROR; DEBUG(D_route) debug_printf("non-directory on path %s: file assumed not to " "exist\n", filename); *yield = FF_NONEXIST; return NULL; case EACCES: /* Permission denied */ - if ((options & RDO_EACCES) == 0) goto DEFAULT_ERROR; + if (!(options & RDO_EACCES)) goto DEFAULT_ERROR; DEBUG(D_route) debug_printf("permission denied for %s: file assumed not to " "exist\n", filename); *yield = FF_NONEXIST; return NULL; - DEFAULT_ERROR: +DEFAULT_ERROR: default: *error = string_open_failed(errno, "%s", filename); *yield = FF_ERROR; @@ -361,7 +373,7 @@ if (*filtertype != FILTER_FORWARD) /* RDO_FILTER is an "allow" bit */ - if ((options & RDO_FILTER) == 0) + if (!(options & RDO_FILTER)) { *error = US"filtering not enabled"; return FF_ERROR; @@ -383,7 +395,7 @@ if (*filtertype != FILTER_FORWARD) } else { - if ((options & RDO_SIEVE_FILTER) != 0) + if (options & RDO_SIEVE_FILTER) { *error = US"Sieve filtering not enabled"; return FF_ERROR; @@ -575,11 +587,9 @@ if (!ugid->uid_set || /* Either there's no uid, or */ (!rdata->isfile && /* We've got the data, and */ rda_is_filter(data) == FILTER_FORWARD && /* It's not a filter script, */ Ustrstr(data, ":include:") == NULL)) /* and there's no :include: */ - { return rda_extract(rdata, options, include_directory, sieve_vacation_directory, sieve_enotify_mailto_owner, sieve_useraddress, sieve_subaddress, generated, error, eblockp, filtertype); - } /* We need to run the processing code in a sub-process. However, if we can determine the non-existence of a file first, we can decline without having to @@ -605,7 +615,7 @@ with the parent process. */ oldsignal = signal(SIGCHLD, SIG_DFL); search_tidyup(); -if ((pid = fork()) == 0) +if ((pid = exim_fork(US"router-interpret")) == 0) { header_line *waslast = header_last; /* Save last header */ @@ -758,7 +768,7 @@ if ((pid = fork()) == 0) out: (void)close(fd); search_tidyup(); - exim_underbar_exit(0); + exim_underbar_exit(EXIT_SUCCESS); bad: DEBUG(D_rewrite) debug_printf("rda_interpret: failed write to pipe\n"); @@ -911,17 +921,17 @@ if (yield == FF_DELIVERED || yield == FF_NOTDELIVERED || sizeof(int) || read(fd,&(addr->reply->once_repeat),sizeof(time_t)) != sizeof(time_t) || - !rda_read_string(fd, &(addr->reply->to)) || - !rda_read_string(fd, &(addr->reply->cc)) || - !rda_read_string(fd, &(addr->reply->bcc)) || - !rda_read_string(fd, &(addr->reply->from)) || - !rda_read_string(fd, &(addr->reply->reply_to)) || - !rda_read_string(fd, &(addr->reply->subject)) || - !rda_read_string(fd, &(addr->reply->headers)) || - !rda_read_string(fd, &(addr->reply->text)) || - !rda_read_string(fd, &(addr->reply->file)) || - !rda_read_string(fd, &(addr->reply->logfile)) || - !rda_read_string(fd, &(addr->reply->oncelog))) + !rda_read_string(fd, &addr->reply->to) || + !rda_read_string(fd, &addr->reply->cc) || + !rda_read_string(fd, &addr->reply->bcc) || + !rda_read_string(fd, &addr->reply->from) || + !rda_read_string(fd, &addr->reply->reply_to) || + !rda_read_string(fd, &addr->reply->subject) || + !rda_read_string(fd, &addr->reply->headers) || + !rda_read_string(fd, &addr->reply->text) || + !rda_read_string(fd, &addr->reply->file) || + !rda_read_string(fd, &addr->reply->logfile) || + !rda_read_string(fd, &addr->reply->oncelog)) goto DISASTER; } } @@ -932,13 +942,11 @@ reading end of the pipe, and we are done. */ WAIT_EXIT: while ((rc = wait(&status)) != pid) - { if (rc < 0 && errno == ECHILD) /* Process has vanished */ { log_write(0, LOG_MAIN, "redirection process %d vanished unexpectedly", pid); goto FINAL_EXIT; } - } DEBUG(D_route) debug_printf("rda_interpret: subprocess yield=%d error=%s\n", yield, *error);