diff options
Diffstat (limited to 'src/src/verify.c')
| -rw-r--r-- | src/src/verify.c | 2508 |
1 files changed, 2508 insertions, 0 deletions
diff --git a/src/src/verify.c b/src/src/verify.c new file mode 100644 index 000000000..bae410e67 --- /dev/null +++ b/src/src/verify.c @@ -0,0 +1,2508 @@ +/* $Cambridge: exim/src/src/verify.c,v 1.1 2004/10/07 10:39:01 ph10 Exp $ */ + +/************************************************* +* Exim - an Internet mail transport agent * +*************************************************/ + +/* Copyright (c) University of Cambridge 1995 - 2004 */ +/* See the file NOTICE for conditions of use and distribution. */ + +/* Functions concerned with verifying things. The original code for callout +caching was contributed by Kevin Fleming (but I hacked it around a bit). */ + + +#include "exim.h" + + +/* Structure for caching DNSBL lookups */ + +typedef struct dnsbl_cache_block { + dns_address *rhs; + uschar *text; + int rc; + BOOL text_set; +} dnsbl_cache_block; + + +/* Anchor for DNSBL cache */ + +static tree_node *dnsbl_cache = NULL; + + + +/************************************************* +* Retrieve a callout cache record * +*************************************************/ + +/* If a record exists, check whether it has expired. + +Arguments: + dbm_file an open hints file + key the record key + type "address" or "domain" + positive_expire expire time for positive records + negative_expire expire time for negative records + +Returns: the cache record if a non-expired one exists, else NULL +*/ + +static dbdata_callout_cache * +get_callout_cache_record(open_db *dbm_file, uschar *key, uschar *type, + int positive_expire, int negative_expire) +{ +BOOL negative; +int length, expire; +time_t now; +dbdata_callout_cache *cache_record; + +cache_record = dbfn_read_with_length(dbm_file, key, &length); + +if (cache_record == NULL) + { + HDEBUG(D_verify) debug_printf("callout cache: no %s record found\n", type); + return NULL; + } + +/* We treat a record as "negative" if its result field is not positive, or if +it is a domain record and the postmaster field is negative. */ + +negative = cache_record->result != ccache_accept || + (type[0] == 'd' && cache_record->postmaster_result == ccache_reject); +expire = negative? negative_expire : positive_expire; +now = time(NULL); + +if (now - cache_record->time_stamp > expire) + { + HDEBUG(D_verify) debug_printf("callout cache: %s record expired\n", type); + return NULL; + } + +/* If this is a non-reject domain record, check for the obsolete format version +that doesn't have the postmaster and random timestamps, by looking at the +length. If so, copy it to a new-style block, replicating the record's +timestamp. Then check the additional timestamps. (There's no point wasting +effort if connections are rejected.) */ + +if (type[0] == 'd' && cache_record->result != ccache_reject) + { + if (length == sizeof(dbdata_callout_cache_obs)) + { + dbdata_callout_cache *new = store_get(sizeof(dbdata_callout_cache)); + memcpy(new, cache_record, length); + new->postmaster_stamp = new->random_stamp = new->time_stamp; + cache_record = new; + } + + if (now - cache_record->postmaster_stamp > expire) + cache_record->postmaster_result = ccache_unknown; + + if (now - cache_record->random_stamp > expire) + cache_record->random_result = ccache_unknown; + } + +HDEBUG(D_verify) debug_printf("callout cache: found %s record\n", type); +return cache_record; +} + + + +/************************************************* +* Do callout verification for an address * +*************************************************/ + +/* This function is called from verify_address() when the address has routed to +a host list, and a callout has been requested. Callouts are expensive; that is +why a cache is used to improve the efficiency. + +Arguments: + addr the address that's been routed + host_list the list of hosts to try + tf the transport feedback block + + ifstring "interface" option from transport, or NULL + portstring "port" option from transport, or NULL + protocolstring "protocol" option from transport, or NULL + callout the per-command callout timeout + callout_overall the overall callout timeout (if < 0; use 4*callout) + options the verification options - these bits are used: + vopt_is_recipient => this is a recipient address + vopt_callout_no_cache => don't use callout cache + vopt_callout_random => do the "random" thing + vopt_callout_recipsender => use real sender for recipient + vopt_callout_recippmaster => use postmaster for recipient + se_mailfrom MAIL FROM address for sender verify; NULL => "" + pm_mailfrom if non-NULL, do the postmaster check with this sender + +Returns: OK/FAIL/DEFER +*/ + +static int +do_callout(address_item *addr, host_item *host_list, transport_feedback *tf, + int callout, int callout_overall, int options, uschar *se_mailfrom, + uschar *pm_mailfrom) +{ +BOOL is_recipient = (options & vopt_is_recipient) != 0; +BOOL callout_no_cache = (options & vopt_callout_no_cache) != 0; +BOOL callout_random = (options & vopt_callout_random) != 0; + +int yield = OK; +BOOL done = FALSE; +uschar *address_key; +uschar *from_address; +uschar *random_local_part = NULL; +open_db dbblock; +open_db *dbm_file = NULL; +dbdata_callout_cache new_domain_record; +dbdata_callout_cache_address new_address_record; +host_item *host; +time_t callout_start_time; + +new_domain_record.result = ccache_unknown; +new_domain_record.postmaster_result = ccache_unknown; +new_domain_record.random_result = ccache_unknown; + +memset(&new_address_record, 0, sizeof(new_address_record)); + +/* For a recipient callout, the key used for the address cache record must +include the sender address if we are using the real sender in the callout, +because that may influence the result of the callout. */ + +address_key = addr->address; +from_address = US""; + +if (is_recipient) + { + if ((options & vopt_callout_recipsender) != 0) + { + address_key = string_sprintf("%s/<%s>", addr->address, sender_address); + from_address = sender_address; + } + else if ((options & vopt_callout_recippmaster) != 0) + { + address_key = string_sprintf("%s/<postmaster@%s>", addr->address, + qualify_domain_sender); + from_address = string_sprintf("postmaster@%s", qualify_domain_sender); + } + } + +/* For a sender callout, we must adjust the key if the mailfrom address is not +empty. */ + +else + { + from_address = (se_mailfrom == NULL)? US"" : se_mailfrom; + if (from_address[0] != 0) + address_key = string_sprintf("%s/<%s>", addr->address, from_address); + } + +/* Open the callout cache database, it it exists, for reading only at this +stage, unless caching has been disabled. */ + +if (callout_no_cache) + { + HDEBUG(D_verify) debug_printf("callout cache: disabled by no_cache\n"); + } +else if ((dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE)) == NULL) + { + HDEBUG(D_verify) debug_printf("callout cache: not available\n"); + } + +/* If a cache database is available see if we can avoid the need to do an +actual callout by making use of previously-obtained data. */ + +if (dbm_file != NULL) + { + dbdata_callout_cache_address *cache_address_record; + dbdata_callout_cache *cache_record = get_callout_cache_record(dbm_file, + addr->domain, US"domain", + callout_cache_domain_positive_expire, + callout_cache_domain_negative_expire); + + /* If an unexpired cache record was found for this domain, see if the callout + process can be short-circuited. */ + + if (cache_record != NULL) + { + /* If an early command (up to and including MAIL FROM:<>) was rejected, + there is no point carrying on. The callout fails. */ + + if (cache_record->result == ccache_reject) + { + setflag(addr, af_verify_nsfail); + HDEBUG(D_verify) + debug_printf("callout cache: domain gave initial rejection, or " + "does not accept HELO or MAIL FROM:<>\n"); + setflag(addr, af_verify_nsfail); + addr->user_message = US"(result of an earlier callout reused)."; + yield = FAIL; + goto END_CALLOUT; + } + + /* If a previous check on a "random" local part was accepted, we assume + that the server does not do any checking on local parts. There is therefore + no point in doing the callout, because it will always be successful. If a + random check previously failed, arrange not to do it again, but preserve + the data in the new record. If a random check is required but hasn't been + done, skip the remaining cache processing. */ + + if (callout_random) switch(cache_record->random_result) + { + case ccache_accept: + HDEBUG(D_verify) + debug_printf("callout cache: domain accepts random addresses\n"); + goto END_CALLOUT; /* Default yield is OK */ + + case ccache_reject: + HDEBUG(D_verify) + debug_printf("callout cache: domain rejects random addresses\n"); + callout_random = FALSE; + new_domain_record.random_result = ccache_reject; + new_domain_record.random_stamp = cache_record->random_stamp; + break; + + default: + HDEBUG(D_verify) + debug_printf("callout cache: need to check random address handling " + "(not cached or cache expired)\n"); + goto END_CACHE; + } + + /* If a postmaster check is requested, but there was a previous failure, + there is again no point in carrying on. If a postmaster check is required, + but has not been done before, we are going to have to do a callout, so skip + remaining cache processing. */ + + if (pm_mailfrom != NULL) + { + if (cache_record->postmaster_result == ccache_reject) + { + setflag(addr, af_verify_pmfail); + HDEBUG(D_verify) + debug_printf("callout cache: domain does not accept " + "RCPT TO:<postmaster@domain>\n"); + yield = FAIL; + setflag(addr, af_verify_pmfail); + addr->user_message = US"(result of earlier verification reused)."; + goto END_CALLOUT; + } + if (cache_record->postmaster_result == ccache_unknown) + { + HDEBUG(D_verify) + debug_printf("callout cache: need to check RCPT " + "TO:<postmaster@domain> (not cached or cache expired)\n"); + goto END_CACHE; + } + + /* If cache says OK, set pm_mailfrom NULL to prevent a redundant + postmaster check if the address itself has to be checked. Also ensure + that the value in the cache record is preserved (with its old timestamp). + */ + + HDEBUG(D_verify) debug_printf("callout cache: domain accepts RCPT " + "TO:<postmaster@domain>\n"); + pm_mailfrom = NULL; + new_domain_record.postmaster_result = ccache_accept; + new_domain_record.postmaster_stamp = cache_record->postmaster_stamp; + } + } + + /* We can't give a result based on information about the domain. See if there + is an unexpired cache record for this specific address (combined with the + sender address if we are doing a recipient callout with a non-empty sender). + */ + + cache_address_record = (dbdata_callout_cache_address *) + get_callout_cache_record(dbm_file, + address_key, US"address", + callout_cache_positive_expire, + callout_cache_negative_expire); + + if (cache_address_record != NULL) + { + if (cache_address_record->result == ccache_accept) + { + HDEBUG(D_verify) + debug_printf("callout cache: address record is positive\n"); + } + else + { + HDEBUG(D_verify) + debug_printf("callout cache: address record is negative\n"); + addr->user_message = US"Previous (cached) callout verification failure"; + yield = FAIL; + } + goto END_CALLOUT; + } + + /* Close the cache database while we actually do the callout for real. */ + + END_CACHE: + dbfn_close(dbm_file); + dbm_file = NULL; + } + +/* The information wasn't available in the cache, so we have to do a real +callout and save the result in the cache for next time, unless no_cache is set, +or unless we have a previously cached negative random result. If we are to test +with a random local part, ensure that such a local part is available. If not, +log the fact, but carry on without randomming. */ + +if (callout_random && callout_random_local_part != NULL) + { + random_local_part = expand_string(callout_random_local_part); + if (random_local_part == NULL) + log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand " + "callout_random_local_part: %s", expand_string_message); + } + +/* Default the overall callout timeout if not set, and record the time we are +starting so that we can enforce it. */ + +if (callout_overall < 0) callout_overall = 4 * callout; +callout_start_time = time(NULL); + +/* Now make connections to the hosts and do real callouts. The list of hosts +is passed in as an argument. */ + +for (host = host_list; host != NULL && !done; host = host->next) + { + smtp_inblock inblock; + smtp_outblock outblock; + int host_af; + int port = 25; + uschar *helo = US"HELO"; + uschar *interface = NULL; /* Outgoing interface to use; NULL => any */ + uschar inbuffer[4096]; + uschar outbuffer[1024]; + uschar responsebuffer[4096]; + + clearflag(addr, af_verify_pmfail); /* postmaster callout flag */ + clearflag(addr, af_verify_nsfail); /* null sender callout flag */ + + /* Skip this host if we don't have an IP address for it. */ + + if (host->address == NULL) + { + DEBUG(D_verify) debug_printf("no IP address for host name %s: skipping\n", + host->name); + continue; + } + + /* Check the overall callout timeout */ + + if (time(NULL) - callout_start_time >= callout_overall) + { + HDEBUG(D_verify) debug_printf("overall timeout for callout exceeded\n"); + break; + } + + /* Set IPv4 or IPv6 */ + + host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6; + + /* Expand and interpret the interface and port strings. This has to + be delayed till now, because they may expand differently for different + hosts. If there's a failure, log it, but carry on with the defaults. */ + + deliver_host = host->name; + deliver_host_address = host->address; + if (!smtp_get_interface(tf->interface, host_af, addr, NULL, &interface, + US"callout") || + !smtp_get_port(tf->port, addr, &port, US"callout")) + log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address, + addr->message); + deliver_host = deliver_host_address = NULL; + + /* Set HELO string according to the protocol */ + + if (Ustrcmp(tf->protocol, "lmtp") == 0) helo = US"LHLO"; + + HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", interface, port); + + /* Set up the buffer for reading SMTP response packets. */ + + inblock.buffer = inbuffer; + inblock.buffersize = sizeof(inbuffer); + inblock.ptr = inbuffer; + inblock.ptrend = inbuffer; + + /* Set up the buffer for holding SMTP commands while pipelining */ + + outblock.buffer = outbuffer; + outblock.buffersize = sizeof(outbuffer); + outblock.ptr = outbuffer; + outblock.cmd_count = 0; + outblock.authenticating = FALSE; + + /* Connect to the host; on failure, just loop for the next one, but we + set the error for the last one. */ + + inblock.sock = outblock.sock = + smtp_connect(host, host_af, port, interface, callout, TRUE); + if (inblock.sock < 0) + { + addr->message = string_sprintf("could not connect to %s [%s]: %s", + host->name, host->address, strerror(errno)); + continue; + } + + /* Wait for initial response, and then run the initial SMTP commands. The + smtp_write_command() function leaves its command in big_buffer. This is + used in error responses. Initialize it in case the connection is + rejected. */ + + Ustrcpy(big_buffer, "initial connection"); + + done = + smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), + '2', callout) && + + smtp_write_command(&outblock, FALSE, "%s %s\r\n", helo, + smtp_active_hostname) >= 0 && + smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), + '2', callout) && + + smtp_write_command(&outblock, FALSE, "MAIL FROM:<%s>\r\n", + from_address) >= 0 && + smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), + '2', callout); + + /* If the host gave an initial error, or does not accept HELO or MAIL + FROM:<>, arrange to cache this information, but don't record anything for an + I/O error or a defer. Do not cache rejections when a non-empty sender has + been used, because that blocks the whole domain for all senders. */ + + if (!done) + { + if (errno == 0 && responsebuffer[0] == '5') + { + setflag(addr, af_verify_nsfail); + if (from_address[0] == 0) new_domain_record.result = ccache_reject; + } + } + + /* Otherwise, proceed to check a "random" address (if required), then the + given address, and the postmaster address (if required). Between each check, + issue RSET, because some servers accept only one recipient after MAIL + FROM:<>. */ + + else + { + new_domain_record.result = ccache_accept; + + /* Do the random local part check first */ + + if (random_local_part != NULL) + { + uschar randombuffer[1024]; + BOOL random_ok = + smtp_write_command(&outblock, FALSE, + "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part, + addr->domain) >= 0 && + smtp_read_response(&inblock, randombuffer, + sizeof(randombuffer), '2', callout); + + /* Remember when we last did a random test */ + + new_domain_record.random_stamp = time(NULL); + + /* If accepted, we aren't going to do any further tests below. */ + + if (random_ok) + { + new_domain_record.random_result = ccache_accept; + } + + /* Otherwise, cache a real negative response, and get back to the right + state to send RCPT. Unless there's some problem such as a dropped + connection, we expect to succeed, because the commands succeeded above. */ + + else if (errno == 0) + { + if (randombuffer[0] == '5') + new_domain_record.random_result = ccache_reject; + + done = + smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 && + smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), + '2', callout) && + + smtp_write_command(&outblock, FALSE, "MAIL FROM:<>\r\n") >= 0 && + smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), + '2', callout); + } + else done = FALSE; /* Some timeout/connection problem */ + } /* Random check */ + + /* If the host is accepting all local parts, as determined by the "random" + check, we don't need to waste time doing any further checking. */ + + if (new_domain_record.random_result != ccache_accept && done) + { + done = + smtp_write_command(&outblock, FALSE, "RCPT TO:<%.1000s>\r\n", + addr->address) >= 0 && + smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), + '2', callout); + + if (done) + new_address_record.result = ccache_accept; + else if (errno == 0 && responsebuffer[0] == '5') + new_address_record.result = ccache_reject; + + /* Do postmaster check if requested */ + + if (done && pm_mailfrom != NULL) + { + done = + smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 && + smtp_read_response(&inblock, responsebuffer, + sizeof(responsebuffer), '2', callout) && + + smtp_write_command(&outblock, FALSE, + "MAIL FROM:<%s>\r\n", pm_mailfrom) >= 0 && + smtp_read_response(&inblock, responsebuffer, + sizeof(responsebuffer), '2', callout) && + + smtp_write_command(&outblock, FALSE, + "RCPT TO:<postmaster@%.1000s>\r\n", addr->domain) >= 0 && + smtp_read_response(&inblock, responsebuffer, + sizeof(responsebuffer), '2', callout); + + new_domain_record.postmaster_stamp = time(NULL); + + if (done) + new_domain_record.postmaster_result = ccache_accept; + else if (errno == 0 && responsebuffer[0] == '5') + { + setflag(addr, af_verify_pmfail); + new_domain_record.postmaster_result = ccache_reject; + } + } + } /* Random not accepted */ + } /* MAIL FROM:<> accepted */ + + /* For any failure of the main check, other than a negative response, we just + close the connection and carry on. We can identify a negative response by the + fact that errno is zero. For I/O errors it will be non-zero + + Set up different error texts for logging and for sending back to the caller + as an SMTP response. Log in all cases, using a one-line format. For sender + callouts, give a full response to the caller, but for recipient callouts, + don't give the IP address because this may be an internal host whose identity + is not to be widely broadcast. */ + + if (!done) + { + if (errno == ETIMEDOUT) + { + HDEBUG(D_verify) debug_printf("SMTP timeout\n"); + } + else if (errno == 0) + { + if (*responsebuffer == 0) Ustrcpy(responsebuffer, US"connection dropped"); + + addr->message = + string_sprintf("response to \"%s\" from %s [%s] was: %s", + big_buffer, host->name, host->address, + string_printing(responsebuffer)); + + addr->user_message = is_recipient? + string_sprintf("Callout verification failed:\n%s", responsebuffer) + : + string_sprintf("Called: %s\nSent: %s\nResponse: %s", + host->address, big_buffer, responsebuffer); + + /* Hard rejection ends the process */ + + if (responsebuffer[0] == '5') /* Address rejected */ + { + yield = FAIL; + done = TRUE; + } + } + } + + /* End the SMTP conversation and close the connection. */ + + (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n"); + close(inblock.sock); + } /* Loop through all hosts, while !done */ + +/* If we get here with done == TRUE, a successful callout happened, and yield +will be set OK or FAIL according to the response to the RCPT command. +Otherwise, we looped through the hosts but couldn't complete the business. +However, there may be domain-specific information to cache in both cases. + +The value of the result field in the new_domain record is ccache_unknown if +there was an error before or with MAIL FROM:<>, and errno was not zero, +implying some kind of I/O error. We don't want to write the cache in that case. +Otherwise the value is ccache_accept or ccache_reject. */ + +if (!callout_no_cache && new_domain_record.result != ccache_unknown) + { + if ((dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE)) + == NULL) + { + HDEBUG(D_verify) debug_printf("callout cache: not available\n"); + } + else + { + (void)dbfn_write(dbm_file, addr->domain, &new_domain_record, + (int)sizeof(dbdata_callout_cache)); + HDEBUG(D_verify) debug_printf("wrote callout cache domain record:\n" + " result=%d postmaster=%d random=%d\n", + new_domain_record.result, + new_domain_record.postmaster_result, + new_domain_record.random_result); + } + } + +/* If a definite result was obtained for the callout, cache it unless caching +is disabled. */ + +if (done) + { + if (!callout_no_cache && new_address_record.result != ccache_unknown) + { + if (dbm_file == NULL) + dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE); + if (dbm_file == NULL) + { + HDEBUG(D_verify) debug_printf("no callout cache available\n"); + } + else + { + (void)dbfn_write(dbm_file, address_key, &new_address_record, + (int)sizeof(dbdata_callout_cache_address)); + HDEBUG(D_verify) debug_printf("wrote %s callout cache address record\n", + (new_address_record.result == ccache_accept)? "positive" : "negative"); + } + } + } /* done */ + +/* Failure to connect to any host, or any response other than 2xx or 5xx is a +temporary error. If there was only one host, and a response was received, leave +it alone if supplying details. Otherwise, give a generic response. */ + +else /* !done */ + { + uschar *dullmsg = string_sprintf("Could not complete %s verify callout", + is_recipient? "recipient" : "sender"); + yield = DEFER; + + if (host_list->next != NULL || addr->message == NULL) addr->message = dullmsg; + + addr->user_message = (!smtp_return_error_details)? dullmsg : + string_sprintf("%s for <%s>.\n" + "The mail server(s) for the domain may be temporarily unreachable, or\n" + "they may be permanently unreachable from this server. In the latter case,\n%s", + dullmsg, addr->address, + is_recipient? + "the address will never be accepted." + : + "you need to change the address or create an MX record for its domain\n" + "if it is supposed to be generally accessible from the Internet.\n" + "Talk to your mail administrator for details."); + + /* Force a specific error code */ + + addr->basic_errno = ERRNO_CALLOUTDEFER; + } + +/* Come here from within the cache-reading code on fast-track exit. */ + +END_CALLOUT: +if (dbm_file != NULL) dbfn_close(dbm_file); +return yield; +} + + + +/************************************************* +* Copy error to toplevel address * +*************************************************/ + +/* This function is used when a verify fails or defers, to ensure that the +failure or defer information is in the original toplevel address. This applies +when an address is redirected to a single new address, and the failure or +deferral happens to the child address. + +Arguments: + vaddr the verify address item + addr the final address item + yield FAIL or DEFER + +Returns: the value of YIELD +*/ + +static int +copy_error(address_item *vaddr, address_item *addr, int yield) +{ +if (addr != vaddr) + { + vaddr->message = addr->message; + vaddr->user_message = addr->user_message; + vaddr->basic_errno = addr->basic_errno; + vaddr->more_errno = addr->more_errno; + } +return yield; +} + + + + +/************************************************* +* Verify an email address * +*************************************************/ + +/* This function is used both for verification (-bv and at other times) and +address testing (-bt), which is indicated by address_test_mode being set. + +Arguments: + vaddr contains the address to verify; the next field in this block + must be NULL + f if not NULL, write the result to this file + options various option bits: + vopt_fake_sender => this sender verify is not for the real + sender (it was verify=sender=xxxx or an address from a + header line) - rewriting must not change sender_address + vopt_is_recipient => this is a recipient address, otherwise + it's a sender address - this affects qualification and + rewriting and messages from callouts + vopt_qualify => qualify an unqualified address; else error + vopt_expn => called from SMTP EXPN command + + These ones are used by do_callout() -- the options variable + is passed to it. + + vopt_callout_no_cache => don't use callout cache + vopt_callout_random => do the "random" thing + vopt_callout_recipsender => use real sender for recipient + vopt_callout_recippmaster => use postmaster for recipient + + callout if > 0, specifies that callout is required, and gives timeout + for individual connections and commands + callout_overall if > 0, gives overall timeout for the callout function; + if < 0, a default is used (see do_callout()) + se_mailfrom when callout is requested to verify a sender, use this + in MAIL FROM; NULL => "" + pm_mailfrom when callout is requested, if non-NULL, do the postmaster + thing and use this as the sender address (may be "") + + routed if not NULL, set TRUE if routing succeeded, so we can + distinguish between routing failed and callout failed + +Returns: OK address verified + FAIL address failed to verify + DEFER can't tell at present +*/ + +int +verify_address(address_item *vaddr, FILE *f, int options, int callout, + int callout_overall, uschar *se_mailfrom, uschar *pm_mailfrom, BOOL *routed) +{ +BOOL allok = TRUE; +BOOL full_info = (f == NULL)? FALSE : (debug_selector != 0); +BOOL is_recipient = (options & vopt_is_recipient) != 0; +BOOL expn = (options & vopt_expn) != 0; + +int i; +int yield = OK; +int verify_type = expn? v_expn : + address_test_mode? v_none : + is_recipient? v_recipient : v_sender; +address_item *addr_list; +address_item *addr_new = NULL; +address_item *addr_remote = NULL; +address_item *addr_local = NULL; +address_item *addr_succeed = NULL; +uschar *ko_prefix, *cr; +uschar *address = vaddr->address; +uschar *save_sender; +uschar null_sender[] = { 0 }; /* Ensure writeable memory */ + +/* Set up a prefix and suffix for error message which allow us to use the same +output statements both in EXPN mode (where an SMTP response is needed) and when +debugging with an output file. */ + +if (expn) + { + ko_prefix = US"553 "; + cr = US"\r"; + } +else ko_prefix = cr = US""; + +/* Add qualify domain if permitted; otherwise an unqualified address fails. */ + +if (parse_find_at(address) == NULL) + { + if ((options & vopt_qualify) == 0) + { + if (f != NULL) + fprintf(f, "%sA domain is required for \"%s\"%s\n", ko_prefix, address, + cr); + return FAIL; + } + address = rewrite_address_qualify(address, is_recipient); + } + +DEBUG(D_verify) + { + debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); + debug_printf("%s %s\n", address_test_mode? "Testing" : "Verifying", address); + } + +/* Rewrite and report on it. Clear the domain and local part caches - these +may have been set by domains and local part tests during an ACL. */ + +if (global_rewrite_rules != NULL) + { + uschar *old = address; + address = rewrite_address(address, is_recipient, FALSE, + global_rewrite_rules, rewrite_existflags); + if (address != old) + { + for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->localpart_cache[i] = 0; + for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->domain_cache[i] = 0; + if (f != NULL && !expn) fprintf(f, "Address rewritten as: %s\n", address); + } + } + +/* If this is the real sender address, we must update sender_address at +this point, because it may be referred to in the routers. */ + +if ((options & (vopt_fake_sender|vopt_is_recipient)) == 0) + sender_address = address; + +/* If the address was rewritten to <> no verification can be done, and we have +to return OK. This rewriting is permitted only for sender addresses; for other +addresses, such rewriting fails. */ + +if (address[0] == 0) return OK; + +/* Save a copy of the sender address for re-instating if we change it to <> +while verifying a sender address (a nice bit of self-reference there). */ + +save_sender = sender_address; + +/* Update the address structure with the possibly qualified and rewritten +address. Set it up as the starting address on the chain of new addresses. */ + +vaddr->address = address; +addr_new = vaddr; + +/* We need a loop, because an address can generate new addresses. We must also +cope with generated pipes and files at the top level. (See also the code and +comment in deliver.c.) However, it is usually the case that the router for +user's .forward files has its verify flag turned off. + +If an address generates more than one child, the loop is used only when +full_info is set, and this can only be set locally. Remote enquiries just get +information about the top level address, not anything that it generated. */ + +while (addr_new != NULL) + { + int rc; + address_item *addr = addr_new; + + addr_new = addr->next; + addr->next = NULL; + + DEBUG(D_verify) + { + debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); + debug_printf("Considering %s\n", addr->address); + } + + /* Handle generated pipe, file or reply addresses. We don't get these + when handling EXPN, as it does only one level of expansion. */ + + if (testflag(addr, af_pfr)) + { + allok = FALSE; + if (f != NULL) + { + BOOL allow; + + if (addr->address[0] == '>') + { + allow = testflag(addr, af_allow_reply); + fprintf(f, "%s -> mail %s", addr->parent->address, addr->address + 1); + } + else + { + allow = (addr->address[0] == '|')? + testflag(addr, af_allow_pipe) : testflag(addr, af_allow_file); + fprintf(f, "%s -> %s", addr->parent->address, addr->address); + } + + if (addr->basic_errno == ERRNO_BADTRANSPORT) + fprintf(f, "\n*** Error in setting up pipe, file, or autoreply:\n" + "%s\n", addr->message); + else if (allow) + fprintf(f, "\n transport = %s\n", addr->transport->name); + else + fprintf(f, " *** forbidden ***\n"); + } + continue; + } + + /* Just in case some router parameter refers to it. */ + + return_path = (addr->p.errors_address != NULL)? + addr->p.errors_address : sender_address; + + /* Split the address into domain and local part, handling the %-hack if + necessary, and then route it. While routing a sender address, set + $sender_address to <> because that is what it will be if we were trying to + send a bounce to the sender. */ + + if (routed != NULL) *routed = FALSE; + if ((rc = deliver_split_address(addr)) == OK) + { + if (!is_recipient) sender_address = null_sender; + rc = route_address(addr, &addr_local, &addr_remote, &addr_new, + &addr_succeed, verify_type); + sender_address = save_sender; /* Put back the real sender */ + } + + /* If routing an address succeeded, set the flag that remembers, for use when + an ACL cached a sender verify (in case a callout fails). Then if routing set + up a list of hosts or the transport has a host list, and the callout option + is set, and we aren't in a host checking run, do the callout verification, + and set another flag that notes that a callout happened. */ + + if (rc == OK) + { + if (routed != NULL) *routed = TRUE; + if (callout > 0) + { + host_item *host_list = addr->host_list; + + /* Default, if no remote transport, to NULL for the interface (=> any), + "smtp" for the port, and "smtp" for the protocol. */ + + transport_feedback tf = { NULL, US"smtp", US"smtp", NULL, FALSE, FALSE }; + + /* If verification yielded a remote transport, we want to use that + transport's options, so as to mimic what would happen if we were really + sending a message to this address. */ + + if (addr->transport != NULL && !addr->transport->info->local) + { + (void)(addr->transport->setup)(addr->transport, addr, &tf, NULL); + + /* If the transport has hosts and the router does not, or if the + transport is configured to override the router's hosts, we must build a + host list of the transport's hosts, and find the IP addresses */ + + if (tf.hosts != NULL && (host_list == NULL || tf.hosts_override)) + { + uschar *s; + + host_list = NULL; /* Ignore the router's hosts */ + + deliver_domain = addr->domain; + deliver_localpart = addr->local_part; + s = expand_string(tf.hosts); + deliver_domain = deliver_localpart = NULL; + + if (s == NULL) + { + log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand list of hosts " + "\"%s\" in %s transport for callout: %s", tf.hosts, + addr->transport->name, expand_string_message); + } + else + { + uschar *canonical_name; + host_item *host; + host_build_hostlist(&host_list, s, tf.hosts_randomize); + + /* Just ignore failures to find a host address. If we don't manage + to find any addresses, the callout will defer. */ + + for (host = host_list; host != NULL; host = host->next) + { + if (tf.gethostbyname || string_is_ip_address(host->name, NULL)) + (void)host_find_byname(host, NULL, &canonical_name, TRUE); + else + { + int flags = HOST_FIND_BY_A; + if (tf.qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE; + if (tf.search_parents) flags |= HOST_FIND_SEARCH_PARENTS; + (void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL, + &canonical_name, NULL); + } + } + } + } + } + + /* Can only do a callout if we have at least one host! */ + + if (host_list != NULL) + { + HDEBUG(D_verify) debug_printf("Attempting full verification using callout\n"); + if (host_checking && !host_checking_callout) + { + HDEBUG(D_verify) + debug_printf("... callout omitted by default when host testing\n" + "(Use -bhc if you want the callouts to happen.)\n"); + } + else + { + rc = do_callout(addr, host_list, &tf, callout, callout_overall, + options, se_mailfrom, pm_mailfrom); + } + } + else + { + HDEBUG(D_verify) debug_printf("Cannot do callout: neither router nor " + "transport provided a host list\n"); + } + } + } + + /* A router may return REROUTED if it has set up a child address as a result + of a change of domain name (typically from widening). In this case we always + want to continue to verify the new child. */ + + if (rc == REROUTED) continue; + + /* Handle hard failures */ + + if (rc == FAIL) + { + allok = FALSE; + if (f != NULL) + { + fprintf(f, "%s%s %s", ko_prefix, address, + address_test_mode? "is undeliverable" : "failed to verify"); + if (!expn && admin_user) + { + if (addr->basic_errno > 0) + fprintf(f, ": %s", strerror(addr->basic_errno)); + if (addr->message != NULL) + fprintf(f, ":\n %s", addr->message); + } + fprintf(f, "%s\n", cr); + } + + if (!full_info) return copy_error(vaddr, addr, FAIL); + else yield = FAIL; + } + + /* Soft failure */ + + else if (rc == DEFER) + { + allok = FALSE; + if (f != NULL) + { + fprintf(f, "%s%s cannot be resolved at this time", ko_prefix, address); + if (!expn && admin_user) + { + if (addr->basic_errno > 0) + fprintf(f, ":\n %s", strerror(addr->basic_errno)); + if (addr->message != NULL) + fprintf(f, ":\n %s", addr->message); + else if (addr->basic_errno <= 0) + fprintf(f, ":\n unknown error"); + } + + fprintf(f, "%s\n", cr); + } + if (!full_info) return copy_error(vaddr, addr, DEFER); + else if (yield == OK) yield = DEFER; + } + + /* If we are handling EXPN, we do not want to continue to route beyond + the top level. */ + + else if (expn) + { + uschar *ok_prefix = US"250-"; + if (addr_new == NULL) + { + if (addr_local == NULL && addr_remote == NULL) + fprintf(f, "250 mail to <%s> is discarded\r\n", address); + else + fprintf(f, "250 <%s>\r\n", address); + } + else while (addr_new != NULL) + { + address_item *addr2 = addr_new; + addr_new = addr2->next; + if (addr_new == NULL) ok_prefix = US"250 "; + fprintf(f, "%s<%s>\r\n", ok_prefix, addr2->address); + } + return OK; + } + + /* Successful routing other than EXPN. */ + + else + { + /* Handle successful routing when short info wanted. Otherwise continue for + other (generated) addresses. Short info is the operational case. Full info + can be requested only when debug_selector != 0 and a file is supplied. + + There is a conflict between the use of aliasing as an alternate email + address, and as a sort of mailing list. If an alias turns the incoming + address into just one address (e.g. J.Caesar->jc44) you may well want to + carry on verifying the generated address to ensure it is valid when + checking incoming mail. If aliasing generates multiple addresses, you + probably don't want to do this. Exim therefore treats the generation of + just a single new address as a special case, and continues on to verify the + generated address. */ + + if (!full_info && /* Stop if short info wanted AND */ + (addr_new == NULL || /* No new address OR */ + addr_new->next != NULL || /* More than one new address OR */ + testflag(addr_new, af_pfr))) /* New address is pfr */ + { + if (f != NULL) fprintf(f, "%s %s\n", address, + address_test_mode? "is deliverable" : "verified"); + + /* If we have carried on to verify a child address, we want the value + of $address_data to be that of the child */ + + vaddr->p.address_data = addr->p.address_data; + return OK; + } + } + } /* Loop for generated addresses */ + +/* Display the full results of the successful routing, including any generated +addresses. Control gets here only when full_info is set, which requires f not +to be NULL, and this occurs only when a top-level verify is called with the +debugging switch on. + +If there are no local and no remote addresses, and there were no pipes, files, +or autoreplies, and there were no errors or deferments, the message is to be +discarded, usually because of the use of :blackhole: in an alias file. */ + +if (allok && addr_local == NULL && addr_remote == NULL) + fprintf(f, "mail to %s is discarded\n", address); + +else for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++) + { + while (addr_list != NULL) + { + address_item *addr = addr_list; + address_item *p = addr->parent; + addr_list = addr->next; + + fprintf(f, "%s", CS addr->address); + while (p != NULL) + { + fprintf(f, "\n <-- %s", p->address); + p = p->parent; + } + fprintf(f, "\n "); + + /* Show router, and transport */ + + fprintf(f, "router = %s, ", addr->router->name); + fprintf(f, "transport = %s\n", (addr->transport == NULL)? US"unset" : + addr->transport->name); + + /* Show any hosts that are set up by a router unless the transport + is going to override them; fiddle a bit to get a nice format. */ + + if (addr->host_list != NULL && addr->transport != NULL && + !addr->transport->overrides_hosts) + { + host_item *h; + int maxlen = 0; + int maxaddlen = 0; + for (h = addr->host_list; h != NULL; h = h->next) + { + int len = Ustrlen(h->name); + if (len > maxlen) maxlen = len; + len = (h->address != NULL)? Ustrlen(h->address) : 7; + if (len > maxaddlen) maxaddlen = len; + } + for (h = addr->host_list; h != NULL; h = h->next) + { + int len = Ustrlen(h->name); + fprintf(f, " host %s ", h->name); + while (len++ < maxlen) fprintf(f, " "); + if (h->address != NULL) + { + fprintf(f, "[%s] ", h->address); + len = Ustrlen(h->address); + } + else if (!addr->transport->info->local) /* Omit [unknown] for local */ + { + fprintf(f, "[unknown] "); + len = 7; + } + else len = -3; + while (len++ < maxaddlen) fprintf(f," "); + if (h->mx >= 0) fprintf(f, "MX=%d", h->mx); + if (h->port != PORT_NONE) fprintf(f, " port=%d", h->port); + if (h->status == hstatus_unusable) fprintf(f, " ** unusable **"); + fprintf(f, "\n"); + } + } + } + } + +return yield; /* Will be DEFER or FAIL if any one address has */ +} + + + + +/************************************************* +* Check headers for syntax errors * +*************************************************/ + +/* This function checks those header lines that contain addresses, and verifies +that all the addresses therein are syntactially correct. + +Arguments: + msgptr where to put an error message + +Returns: OK + FAIL +*/ + +int +verify_check_headers(uschar **msgptr) +{ +header_line *h; +uschar *colon, *s; + +for (h = header_list; h != NULL; h = h->next) + { + if (h->type != htype_from && + h->type != htype_reply_to && + h->type != htype_sender && + h->type != htype_to && + h->type != htype_cc && + h->type != htype_bcc) + continue; + + colon = Ustrchr(h->text, ':'); + s = colon + 1; + while (isspace(*s)) s++; + + parse_allow_group = TRUE; /* Allow group syntax */ + + /* Loop for multiple addresses in the header */ + + while (*s != 0) + { + uschar *ss = parse_find_address_end(s, FALSE); + uschar *recipient, *errmess; + int terminator = *ss; + int start, end, domain; + + /* Temporarily terminate the string at this point, and extract the + operative address within. */ + + *ss = 0; + recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE); + *ss = terminator; + + /* Permit an unqualified address only if the message is local, or if the + sending host is configured to be permitted to send them. */ + + if (recipient != NULL && domain == 0) + { + if (h->type == htype_from || h->type == htype_sender) + { + if (!allow_unqualified_sender) recipient = NULL; + } + else + { + if (!allow_unqualified_recipient) recipient = NULL; + } + if (recipient == NULL) errmess = US"unqualified address not permitted"; + } + + /* It's an error if no address could be extracted, except for the special + case of an empty address. */ + + if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0) + { + uschar *verb = US"is"; + uschar *t = ss; + int len; + + /* Arrange not to include any white space at the end in the + error message. */ + + while (t > s && isspace(t[-1])) t--; + + /* Add the address which failed to the error message, since in a + header with very many addresses it is sometimes hard to spot + which one is at fault. However, limit the amount of address to + quote - cases have been seen where, for example, a missing double + quote in a humungous To: header creates an "address" that is longer + than string_sprintf can handle. */ + + len = t - s; + if (len > 1024) + { + len = 1024; + verb = US"begins"; + } + + *msgptr = string_printing( + string_sprintf("%s: failing address in \"%.*s\" header %s: %.*s", + errmess, colon - h->text, h->text, verb, len, s)); + + return FAIL; + } + + /* Advance to the next address */ + + s = ss + (terminator? 1:0); + while (isspace(*s)) s++; + } /* Next address */ + } /* Next header */ + +return OK; +} + + + + +/************************************************* +* Find if verified sender * +*************************************************/ + +/* Usually, just a single address is verified as the sender of the message. +However, Exim can be made to verify other addresses as well (often related in +some way), and this is useful in some environments. There may therefore be a +chain of such addresses that have previously been tested. This function finds +whether a given address is on the chain. + +Arguments: the address to be verified +Returns: pointer to an address item, or NULL +*/ + +address_item * +verify_checked_sender(uschar *sender) +{ +address_item *addr; +for (addr = sender_verified_list; addr != NULL; addr = addr->next) + if (Ustrcmp(sender, addr->address) == 0) break; +return addr; +} + + + + + +/************************************************* +* Get valid header address * +*************************************************/ + +/* Scan the originator headers of the message, looking for an address that +verifies successfully. RFC 822 says: + + o The "Sender" field mailbox should be sent notices of + any problems in transport or delivery of the original + messages. If there is no "Sender" field, then the + "From" field mailbox should be used. + + o If the "Reply-To" field exists, then the reply should + go to the addresses indicated in that field and not to + the address(es) indicated in the "From" field. + +So we check a Sender field if there is one, else a Reply_to field, else a From +field. As some strange messages may have more than one of these fields, +especially if they are resent- fields, check all of them if there is more than +one. + +Arguments: + user_msgptr points to where to put a user error message + log_msgptr points to where to put a log error message + callout timeout for callout check (passed to verify_address()) + callout_overall overall callout timeout (ditto) + se_mailfrom mailfrom for verify; NULL => "" + pm_mailfrom sender for pm callout check (passed to verify_address()) + options callout options (passed to verify_address()) + +If log_msgptr is set to something without setting user_msgptr, the caller +normally uses log_msgptr for both things. + +Returns: result of the verification attempt: OK, FAIL, or DEFER; + FAIL is given if no appropriate headers are found +*/ + +int +verify_check_header_address(uschar **user_msgptr, uschar **log_msgptr, + int callout, int callout_overall, uschar *se_mailfrom, uschar *pm_mailfrom, + int options) +{ +static int header_types[] = { htype_sender, htype_reply_to, htype_from }; +int yield = FAIL; +int i; + +for (i = 0; i < 3; i++) + { + header_line *h; + for (h = header_list; h != NULL; h = h->next) + { + int terminator, new_ok; + uschar *s, *ss, *endname; + + if (h->type != header_types[i]) continue; + s = endname = Ustrchr(h->text, ':') + 1; + + while (*s != 0) + { + address_item *vaddr; + + while (isspace(*s) || *s == ',') s++; + if (*s == 0) break; /* End of header */ + + ss = parse_find_address_end(s, FALSE); + + /* The terminator is a comma or end of header, but there may be white + space preceding it (including newline for the last address). Move back + past any white space so we can check against any cached envelope sender + address verifications. */ + + while (isspace(ss[-1])) ss--; + terminator = *ss; + *ss = 0; + + HDEBUG(D_verify) debug_printf("verifying %.*s header address %s\n", + (int)(endname - h->text), h->text, s); + + /* See if we have already verified this address as an envelope sender, + and if so, use the previous answer. */ + + vaddr = verify_checked_sender(s); + + if (vaddr != NULL && /* Previously checked */ + (callout <= 0 || /* No callout needed; OR */ + vaddr->special_action > 256)) /* Callout was done */ + { + new_ok = vaddr->special_action & 255; + HDEBUG(D_verify) debug_printf("previously checked as envelope sender\n"); + *ss = terminator; /* Restore shortened string */ + } + + /* Otherwise we run the verification now. We must restore the shortened + string before running the verification, so the headers are correct, in + case there is any rewriting. */ + + else + { + int start, end, domain; + uschar *address = parse_extract_address(s, log_msgptr, &start, + &end, &domain, FALSE); + + *ss = terminator; + + /* If verification failed because of a syntax error, fail this + function, and ensure that the failing address gets added to the error + message. */ + + if (address == NULL) + { + new_ok = FAIL; + if (*log_msgptr != NULL) + { + while (ss > s && isspace(ss[-1])) ss--; + *log_msgptr = string_sprintf("syntax error in '%.*s' header when " + "scanning for sender: %s in \"%.*s\"", + endname - h->text, h->text, *log_msgptr, ss - s, s); + return FAIL; + } + } + + /* Else go ahead with the sender verification. But is isn't *the* + sender of the message, so set vopt_fake_sender to stop sender_address + being replaced after rewriting or qualification. */ + + else + { + vaddr = deliver_make_addr(address, FALSE); + new_ok = verify_address(vaddr, NULL, options | vopt_fake_sender, + callout, callout_overall, se_mailfrom, pm_mailfrom, NULL); + } + } + + /* We now have the result, either newly found, or cached. If we are + giving out error details, set a specific user error. This means that the + last of these will be returned to the user if all three fail. We do not + set a log message - the generic one below will be used. */ + + if (new_ok != OK && smtp_return_error_details) + { + *user_msgptr = string_sprintf("Rejected after DATA: " + "could not verify \"%.*s\" header address\n%s: %s", + endname - h->text, h->text, vaddr->address, vaddr->message); + } + + /* Success or defer */ + + if (new_ok == OK) return OK; + if (new_ok == DEFER) yield = DEFER; + + /* Move on to any more addresses in the header */ + + s = ss; + } + } + } + +if (yield == FAIL && *log_msgptr == NULL) + *log_msgptr = US"there is no valid sender in any header line"; + +if (yield == DEFER && *log_msgptr == NULL) + *log_msgptr = US"all attempts to verify a sender in a header line deferred"; + +return yield; +} + + + + +/************************************************* +* Get RFC 1413 identification * +*************************************************/ + +/* Attempt to get an id from the sending machine via the RFC 1413 protocol. If +the timeout is set to zero, then the query is not done. There may also be lists +of hosts and nets which are exempt. To guard against malefactors sending +non-printing characters which could, for example, disrupt a message's headers, +make sure the string consists of printing characters only. + +Argument: + port the port to connect to; usually this is IDENT_PORT (113), but when + running in the test harness with -bh a different value is used. + +Returns: nothing + +Side effect: any received ident value is put in sender_ident (NULL otherwise) +*/ + +void +verify_get_ident(int port) +{ +int sock, host_af, qlen; +int received_sender_port, received_interface_port, n; +uschar *p; +uschar buffer[2048]; + +/* Default is no ident. Check whether we want to do an ident check for this +host. */ + +sender_ident = NULL; +if (rfc1413_query_timeout <= 0 || verify_check_host(&rfc1413_hosts) != OK) + return; + +DEBUG(D_ident) debug_printf("doing ident callback\n"); + +/* Set up a connection to the ident port of the remote host. Bind the local end +to the incoming interface address. If the sender host address is an IPv6 +address, the incoming interface address will also be IPv6. */ + +host_af = (Ustrchr(sender_host_address, ':') == NULL)? AF_INET : AF_INET6; +sock = ip_socket(SOCK_STREAM, host_af); +if (sock < 0) return; + +if (ip_bind(sock, host_af, interface_address, 0) < 0) + { + DEBUG(D_ident) debug_printf("bind socket for ident failed: %s\n", + strerror(errno)); + goto END_OFF; + } + +if (ip_connect(sock, host_af, sender_host_address, port, rfc1413_query_timeout) + < 0) + { + if (errno == ETIMEDOUT && (log_extra_selector & LX_ident_timeout) != 0) + { + log_write(0, LOG_MAIN, "ident connection to %s timed out", + sender_host_address); + } + else + { + DEBUG(D_ident) debug_printf("ident connection to %s failed: %s\n", + sender_host_address, strerror(errno)); + } + goto END_OFF; + } + +/* Construct and send the query. */ + +sprintf(CS buffer, "%d , %d\r\n", sender_host_port, interface_port); +qlen = Ustrlen(buffer); +if (send(sock, buffer, qlen, 0) < 0) + { + DEBUG(D_ident) debug_printf("ident send failed: %s\n", strerror(errno)); + goto END_OFF; + } + +/* Read a response line. We put it into the rest of the buffer, using several +recv() calls if necessary. */ + +p = buffer + qlen; + +for (;;) + { + uschar *pp; + int count; + int size = sizeof(buffer) - (p - buffer); + + if (size <= 0) goto END_OFF; /* Buffer filled without seeing \n. */ + count = ip_recv(sock, p, size, rfc1413_query_timeout); + if (count <= 0) goto END_OFF; /* Read error or EOF */ + + /* Scan what we just read, to see if we have reached the terminating \r\n. Be + generous, and accept a plain \n terminator as well. The only illegal + character is 0. */ + + for (pp = p; pp < p + count; pp++) + { + if (*pp == 0) goto END_OFF; /* Zero octet not allowed */ + if (*pp == '\n') + { + if (pp[-1] == '\r') pp--; + *pp = 0; + goto GOT_DATA; /* Break out of both loops */ + } + } + + /* Reached the end of the data without finding \n. Let the loop continue to + read some more, if there is room. */ + + p = pp; + } + +GOT_DATA: + +/* We have received a line of data. Check it carefully. It must start with the +same two port numbers that we sent, followed by data as defined by the RFC. For +example, + + 12345 , 25 : USERID : UNIX :root + +However, the amount of white space may be different to what we sent. In the +"osname" field there may be several sub-fields, comma separated. The data we +actually want to save follows the third colon. Some systems put leading spaces +in it - we discard those. */ + +if (sscanf(CS buffer + qlen, "%d , %d%n", &received_sender_port, + &received_interface_port, &n) != 2 || + received_sender_port != sender_host_port || + received_interface_port != interface_port) + goto END_OFF; + +p = buffer + qlen + n; +while(isspace(*p)) p++; +if (*p++ != ':') goto END_OFF; +while(isspace(*p)) p++; +if (Ustrncmp(p, "USERID", 6) != 0) goto END_OFF; +p += 6; +while(isspace(*p)) p++; +if (*p++ != ':') goto END_OFF; +while (*p != 0 && *p != ':') p++; +if (*p++ == 0) goto END_OFF; +while(isspace(*p)) p++; +if (*p == 0) goto END_OFF; + +/* The rest of the line is the data we want. We turn it into printing +characters when we save it, so that it cannot mess up the format of any logging +or Received: lines into which it gets inserted. We keep a maximum of 127 +characters. */ + +sender_ident = string_printing(string_copyn(p, 127)); +DEBUG(D_ident) debug_printf("sender_ident = %s\n", sender_ident); + +END_OFF: +close(sock); +return; +} + + + + +/************************************************* +* Match host to a single host-list item * +*************************************************/ + +/* This function compares a host (name or address) against a single item +from a host list. The host name gets looked up if it is needed and is not +already known. The function is called from verify_check_this_host() via +match_check_list(), which is why most of its arguments are in a single block. + +Arguments: + arg the argument block (see below) + ss the host-list item + valueptr where to pass back looked up data, or NULL + error for error message when returning ERROR + +The block contains: + host_name the host name or NULL, implying use sender_host_name and + sender_host_aliases, looking them up if required + host_address the host address + host_ipv4 the IPv4 address taken from an IPv6 one + +Returns: OK matched + FAIL did not match + DEFER lookup deferred + ERROR failed to find the host name or IP address + unknown lookup type specified +*/ + +static int +check_host(void *arg, uschar *ss, uschar **valueptr, uschar **error) +{ +check_host_block *cb = (check_host_block *)arg; +int maskoffset; +BOOL isquery = FALSE; +uschar *semicolon, *t; +uschar **aliases; + +/* Optimize for the special case when the pattern is "*". */ + +if (*ss == '*' && ss[1] == 0) return OK; + +/* If the pattern is empty, it matches only in the case when there is no host - +this can occur in ACL checking for SMTP input using the -bs option. In this +situation, the host address is the empty string. */ + +if (cb->host_address[0] == 0) return (*ss == 0)? OK : FAIL; +if (*ss == 0) return FAIL; + +/* If the pattern is precisely "@" then match against the primary host name; +if it's "@[]" match against the local host's IP addresses. */ + +if (*ss == '@') + { + if (ss[1] == 0) ss = primary_hostname; + else if (Ustrcmp(ss, "@[]") == 0) + { + ip_address_item *ip; + for (ip = host_find_interfaces(); ip != NULL; ip = ip->next) + if (Ustrcmp(ip->address, cb->host_address) == 0) return OK; + return FAIL; + } + } + +/* If the pattern is an IP address, optionally followed by a bitmask count, do +a (possibly masked) comparision with the current IP address. */ + +if (string_is_ip_address(ss, &maskoffset)) + return (host_is_in_net(cb->host_address, ss, maskoffset)? OK : FAIL); + +/* If the item is of the form net[n]-lookup;<file|query> then it is a lookup on +a masked IP network, in textual form. The net- stuff really only applies to +single-key lookups where the key is implicit. For query-style lookups the key +is specified in the query. From release 4.30, the use of net- for query style +is no longer needed, but we retain it for backward compatibility. */ + +if (Ustrncmp(ss, "net", 3) == 0 && (semicolon = Ustrchr(ss, ';')) != NULL) + { + int mlen = 0; + for (t = ss + 3; isdigit(*t); t++) mlen = mlen * 10 + *t - '0'; + if (*t++ == '-') + { + int insize; + int search_type; + int incoming[4]; + void *handle; + uschar *filename, *key, *result; + uschar buffer[64]; + + /* If no mask was supplied, set a negative value */ + + if (mlen == 0 && t == ss+4) mlen = -1; + + /* Find the search type */ + + search_type = search_findtype(t, semicolon - t); + + if (search_type < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", + search_error_message); + + /* Adjust parameters for the type of lookup. For a query-style + lookup, there is no file name, and the "key" is just the query. For + a single-key lookup, the key is the current IP address, masked + appropriately, and reconverted to text form, with the mask appended. */ + + if (mac_islookup(search_type, lookup_querystyle)) + { + filename = NULL; + key = semicolon + 1; + } + else + { + insize = host_aton(cb->host_address, incoming); + host_mask(insize, incoming, mlen); + (void)host_nmtoa(insize, incoming, mlen, buffer); + key = buffer; + filename = semicolon + 1; + } + + /* Now do the actual lookup; note that there is no search_close() because + of the caching arrangements. */ + + handle = search_open(filename, search_type, 0, NULL, NULL); + if (handle == NULL) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", + search_error_message); + result = search_find(handle, filename, key, -1, NULL, 0, 0, NULL); + if (valueptr != NULL) *valueptr = result; + return (result != NULL)? OK : search_find_defer? DEFER: FAIL; + } + } + +/* The pattern is not an IP address or network reference of any kind. That is, +it is a host name pattern. Check the characters of the pattern to see if they +comprise only letters, digits, full stops, and hyphens (the constituents of +domain names). Allow underscores, as they are all too commonly found. Sigh. +Also, if allow_utf8_domains is set, allow top-bit characters. */ + +for (t = ss; *t != 0; t++) + if (!isalnum(*t) && *t != '.' && *t != '-' && *t != '_' && + (!allow_utf8_domains || *t < 128)) break; + +/* If the pattern is a complete domain name, with no fancy characters, look up +its IP address and match against that. Note that a multi-homed host will add +items to the chain. */ + +if (*t == 0) + { + int rc; + host_item h; + h.next = NULL; + h.name = ss; + h.address = NULL; + h.mx = MX_NONE; + rc = host_find_byname(&h, NULL, NULL, FALSE); + if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL) + { + host_item *hh; + for (hh = &h; hh != NULL; hh = hh->next) + { + if (Ustrcmp(hh->address, (Ustrchr(hh->address, ':') == NULL)? + cb->host_ipv4 : cb->host_address) == 0) + return OK; + } + return FAIL; + } + if (rc == HOST_FIND_AGAIN) return DEFER; + *error = string_sprintf("failed to find IP address for %s", ss); + return ERROR; + } + +/* Almost all subsequent comparisons require the host name, and can be done +using the general string matching function. When this function is called for +outgoing hosts, the name is always given explicitly. If it is NULL, it means we +must use sender_host_name and its aliases, looking them up if necessary. */ + +if (cb->host_name != NULL) /* Explicit host name given */ + return match_check_string(cb->host_name, ss, -1, TRUE, TRUE, TRUE, + valueptr); + +/* Host name not given; in principle we need the sender host name and its +aliases. However, for query-style lookups, we do not need the name if the +query does not contain $sender_host_name. From release 4.23, a reference to +$sender_host_name causes it to be looked up, so we don't need to do the lookup +on spec. */ + +if ((semicolon = Ustrchr(ss, ';')) != NULL) + { + uschar *affix; + int partial, affixlen, starflags, id; + + *semicolon = 0; + id = search_findtype_partial(ss, &partial, &affix, &affixlen, &starflags); + *semicolon=';'; + + if (id < 0) /* Unknown lookup type */ + { + log_write(0, LOG_MAIN|LOG_PANIC, "%s in host list item \"%s\"", + search_error_message, ss); + return DEFER; + } + isquery = mac_islookup(id, lookup_querystyle); + } + +if (isquery) + { + switch(match_check_string(US"", ss, -1, TRUE, TRUE, TRUE, valueptr)) + { + case OK: return OK; + case DEFER: return DEFER; + default: return FAIL; + } + } + +/* Not a query-style lookup; must ensure the host name is present, and then we +do a check on the name and all its aliases. */ + +if (sender_host_name == NULL) + { + HDEBUG(D_host_lookup) + debug_printf("sender host name required, to match against %s\n", ss); + if (host_lookup_failed || host_name_lookup() != OK) + { + *error = string_sprintf("failed to find host name for %s", + sender_host_address);; + return ERROR; + } + host_build_sender_fullhost(); + } + +/* Match on the sender host name, using the general matching function */ + +switch(match_check_string(sender_host_name, ss, -1, TRUE, TRUE, TRUE, + valueptr)) + { + case OK: return OK; + case DEFER: return DEFER; + } + +/* If there are aliases, try matching on them. */ + +aliases = sender_host_aliases; +while (*aliases != NULL) + { + switch(match_check_string(*aliases++, ss, -1, TRUE, TRUE, TRUE, valueptr)) + { + case OK: return OK; + case DEFER: return DEFER; + } + } +return FAIL; +} + + + + +/************************************************* +* Check a specific host matches a host list * +*************************************************/ + +/* This function is passed a host list containing items in a number of +different formats and the identity of a host. Its job is to determine whether +the given host is in the set of hosts defined by the list. The host name is +passed as a pointer so that it can be looked up if needed and not already +known. This is commonly the case when called from verify_check_host() to check +an incoming connection. When called from elsewhere the host name should usually +be set. + +This function is now just a front end to match_check_list(), which runs common +code for scanning a list. We pass it the check_host() function to perform a +single test. + +Arguments: + listptr pointer to the host list + cache_bits pointer to cache for named lists, or NULL + host_name the host name or NULL, implying use sender_host_name and + sender_host_aliases, looking them up if required + host_address the IP address + valueptr if not NULL, data from a lookup is passed back here + +Returns: OK if the host is in the defined set + FAIL if the host is not in the defined set, + DEFER if a data lookup deferred (not a host lookup) + +If the host name was needed in order to make a comparison, and could not be +determined from the IP address, the result is FAIL unless the item +"+allow_unknown" was met earlier in the list, in which case OK is returned. */ + +int +verify_check_this_host(uschar **listptr, unsigned int *cache_bits, + uschar *host_name, uschar *host_address, uschar **valueptr) +{ +unsigned int *local_cache_bits = cache_bits; +check_host_block cb; +cb.host_name = host_name; +cb.host_address = host_address; + +if (valueptr != NULL) *valueptr = NULL; + +/* If the host address starts off ::ffff: it is an IPv6 address in +IPv4-compatible mode. Find the IPv4 part for checking against IPv4 +addresses. */ + +cb.host_ipv4 = (Ustrncmp(host_address, "::ffff:", 7) == 0)? + host_address + 7 : host_address; + +return match_check_list(listptr, 0, &hostlist_anchor, &local_cache_bits, + check_host, &cb, MCL_HOST, + (host_address == sender_host_address)? US"host" : host_address, valueptr); +} + + + + +/************************************************* +* Check the remote host matches a list * +*************************************************/ + +/* This is a front end to verify_check_this_host(), created because checking +the remote host is a common occurrence. With luck, a good compiler will spot +the tail recursion and optimize it. If there's no host address, this is +command-line SMTP input - check against an empty string for the address. + +Arguments: + listptr pointer to the host list + +Returns: the yield of verify_check_this_host(), + i.e. OK, FAIL, or DEFER +*/ + +int +verify_check_host(uschar **listptr) +{ +return verify_check_this_host(listptr, sender_host_cache, NULL, + (sender_host_address == NULL)? US"" : sender_host_address, NULL); +} + + + + + +/************************************************* +* Invert an IP address for a DNS black list * +*************************************************/ + +/* +Arguments: + buffer where to put the answer + address the address to invert +*/ + +static void +invert_address(uschar *buffer, uschar *address) +{ +int bin[4]; +uschar *bptr = buffer; + +/* If this is an IPv4 address mapped into IPv6 format, adjust the pointer +to the IPv4 part only. */ + +if (Ustrncmp(address, "::ffff:", 7) == 0) address += 7; + +/* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is +always 1. */ + +if (host_aton(address, bin) == 1) + { + int i; + int x = bin[0]; + for (i = 0; i < 4; i++) + { + sprintf(CS bptr, "%d.", x & 255); + while (*bptr) bptr++; + x >>= 8; + } + } + +/* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses +in any DNS black lists, and the format in which they will be looked up is +unknown. This is just a guess. */ + +#if HAVE_IPV6 +else + { + int i, j; + for (j = 3; j >= 0; j--) + { + int x = bin[j]; + for (i = 0; i < 8; i++) + { + sprintf(CS bptr, "%x.", x & 15); + while (*bptr) bptr++; + x >>= 4; + } + } + } +#endif +} + + + +/************************************************* +* Check host against DNS black lists * +*************************************************/ + +/* This function runs checks against a list of DNS black lists, until one +matches. Each item on the list can be of the form + + domain=ip-address/key + +The domain is the right-most domain that is used for the query, for example, +blackholes.mail-abuse.org. If the IP address is present, there is a match only +if the DNS lookup returns a matching IP address. Several addresses may be +given, comma-separated, for example: x.y.z=127.0.0.1,127.0.0.2. + +If no key is given, what is looked up in the domain is the inverted IP address +of the current client host. If a key is given, it is used to construct the +domain for the lookup. For example, + + dsn.rfc-ignorant.org/$sender_address_domain + +After finding a match in the DNS, the domain is placed in $dnslist_domain, and +then we check for a TXT record for an error message, and if found, save its +value in $dnslist_text. We also cache everything in a tree, to optimize +multiple lookups. + +Note: an address for testing RBL is 192.203.178.39 +Note: an address for testing DUL is 192.203.178.4 +Note: a domain for testing RFCI is example.tld.dsn.rfc-ignorant.org + +Arguments: + listptr the domain/address/data list + +Returns: OK successful lookup (i.e. the address is on the list), or + lookup deferred after +include_unknown + FAIL name not found, or no data found for the given type, or + lookup deferred after +exclude_unknown (default) + DEFER lookup failure, if +defer_unknown was set +*/ + +int +verify_check_dnsbl(uschar **listptr) +{ +int sep = 0; +int defer_return = FAIL; +int old_pool = store_pool; +BOOL invert_result = FALSE; +uschar *list = *listptr; +uschar *domain; +uschar *s; +uschar buffer[1024]; +uschar query[256]; /* DNS domain max length */ +uschar revadd[128]; /* Long enough for IPv6 address */ + +/* Indicate that the inverted IP address is not yet set up */ + +revadd[0] = 0; + +/* Loop through all the domains supplied, until something matches */ + +while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) + { + BOOL frc; + BOOL bitmask = FALSE; + dns_answer dnsa; + dns_scan dnss; + uschar *iplist; + uschar *key; + tree_node *t; + dnsbl_cache_block *cb; + + HDEBUG(D_dnsbl) debug_printf("DNS list check: %s\n", domain); + + /* Deal with special values that change the behaviour on defer */ + + if (domain[0] == '+') + { + if (strcmpic(domain, US"+include_unknown") == 0) defer_return = OK; + else if (strcmpic(domain, US"+exclude_unknown") == 0) defer_return = FAIL; + else if (strcmpic(domain, US"+defer_unknown") == 0) defer_return = DEFER; + else + log_write(0, LOG_MAIN|LOG_PANIC, "unknown item in dnslist (ignored): %s", + domain); + continue; + } + + /* See if there's explicit data to be looked up */ + + key = Ustrchr(domain, '/'); + if (key != NULL) *key++ = 0; + + /* See if there's a list of addresses supplied after the domain name. This is + introduced by an = or a & character; if preceded by ! we invert the result. + */ + + iplist = Ustrchr(domain, '='); + if (iplist == NULL) + { + bitmask = TRUE; + iplist = Ustrchr(domain, '&'); + } + + if (iplist != NULL) + { + if (iplist > domain && iplist[-1] == '!') + { + invert_result = TRUE; + iplist[-1] = 0; + } + *iplist++ = 0; + } + + /* Check that what we have left is a sensible domain name. There is no reason + why these domains should in fact use the same syntax as hosts and email + domains, but in practice they seem to. However, there is little point in + actually causing an error here, because that would no doubt hold up incoming + mail. Instead, I'll just log it. */ + + for (s = domain; *s != 0; s++) + { + if (!isalnum(*s) && *s != '-' && *s != '.') + { + log_write(0, LOG_MAIN, "dnslists domain \"%s\" contains " + "strange characters - is this right?", domain); + break; + } + } + + /* Construct the query by adding the domain onto either the sending host + address, or the given key string. */ + + if (key == NULL) + { + if (sender_host_address == NULL) return FAIL; /* can never match */ + if (revadd[0] == 0) invert_address(revadd, sender_host_address); + frc = string_format(query, sizeof(query), "%s%s", revadd, domain); + } + else + { + frc = string_format(query, sizeof(query), "%s.%s", key, domain); + } + + if (!frc) + { + log_write(0, LOG_MAIN|LOG_PANIC, "dnslist query is too long " + "(ignored): %s...", query); + continue; + } + + /* Look for this query in the cache. */ + + t = tree_search(dnsbl_cache, query); + + /* If not cached from a previous lookup, we must do a DNS lookup, and + cache the result in permanent memory. */ + + if (t == NULL) + { + store_pool = POOL_PERM; + + /* In case this is the first time the DNS resolver is being used. */ + + dns_init(FALSE, FALSE); + + /* Set up a tree entry to cache the lookup */ + + t = store_get(sizeof(tree_node) + Ustrlen(query)); + Ustrcpy(t->name, query); + t->data.ptr = cb = store_get(sizeof(dnsbl_cache_block)); + (void)tree_insertnode(&dnsbl_cache, t); + + /* Do the DNS loopup . */ + + HDEBUG(D_dnsbl) debug_printf("new DNS lookup for %s\n", query); + cb->rc = dns_basic_lookup(&dnsa, query, T_A); + cb->text_set = FALSE; + cb->text = NULL; + cb->rhs = NULL; + + /* If the lookup succeeded, cache the RHS address. The code allows for + more than one address - this was for complete generality and the possible + use of A6 records. However, A6 records have been reduced to experimental + status (August 2001) and may die out. So they may never get used at all, + let alone in dnsbl records. However, leave the code here, just in case. + + Quite apart from one A6 RR generating multiple addresses, there are DNS + lists that return more than one A record, so we must handle multiple + addresses generated in that way as well. */ + + if (cb->rc == DNS_SUCCEED) + { + dns_record *rr; + dns_address **addrp = &(cb->rhs); + for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); + rr != NULL; + rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) + { + if (rr->type == T_A) + { + dns_address *da = dns_address_from_rr(&dnsa, rr); + if (da != NULL) + { + *addrp = da; + while (da->next != NULL) da = da->next; + addrp = &(da->next); + } + } + } + + /* If we didn't find any A records, change the return code. This can + happen when there is a CNAME record but there are no A records for what + it points to. */ + + if (cb->rhs == NULL) cb->rc = DNS_NODATA; + } + + store_pool = old_pool; + } + + /* Previous lookup was cached */ + + else + { + HDEBUG(D_dnsbl) debug_printf("using result of previous DNS lookup\n"); + cb = t->data.ptr; + } + + /* We now have the result of the DNS lookup, either newly done, or cached + from a previous call. If the lookup succeeded, check against the address + list if there is one. This may be a positive equality list (introduced by + "="), a negative equality list (introduced by "!="), a positive bitmask + list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/ + + if (cb->rc == DNS_SUCCEED) + { + dns_address *da = NULL; + uschar *addlist = cb->rhs->address; + + /* For A and AAAA records, there may be multiple addresses from multiple + records. For A6 records (currently not expected to be used) there may be + multiple addresses from a single record. */ + + for (da = cb->rhs->next; da != NULL; da = da->next) + addlist = string_sprintf("%s, %s", addlist, da->address); + + HDEBUG(D_dnsbl) debug_printf("DNS lookup for %s succeeded (yielding %s)\n", + query, addlist); + + /* Address list check; this can be either for equality, or via a bitmask. + In the latter case, all the bits must match. */ + + if (iplist != NULL) + { + int ipsep = ','; + uschar ip[46]; + uschar *ptr = iplist; + + while (string_nextinlist(&ptr, &ipsep, ip, sizeof(ip)) != NULL) + { + /* Handle exact matching */ + if (!bitmask) + { + for (da = cb->rhs; da != NULL; da = da->next) + { + if (Ustrcmp(CS da->address, ip) == 0) break; + } + } + /* Handle bitmask matching */ + else + { + int address[4]; + int mask = 0; + + /* At present, all known DNS blocking lists use A records, with + IPv4 addresses on the RHS encoding the information they return. I + wonder if this will linger on as the last vestige of IPv4 when IPv6 + is ubiquitous? Anyway, for now we use paranoia code to completely + ignore IPv6 addresses. The default mask is 0, which always matches. + We change this only for IPv4 addresses in the list. */ + + if (host_aton(ip, address) == 1) mask = address[0]; + + /* Scan the returned addresses, skipping any that are IPv6 */ + + for (da = cb->rhs; da != NULL; da = da->next) + { + if (host_aton(da->address, address) != 1) continue; + if ((address[0] & mask) == mask) break; + } + } + + /* Break out if a match has been found */ + + if (da != NULL) break; + } + + /* If either + + (a) No IP address in a positive list matched, or + (b) An IP address in a negative list did match + + then behave as if the DNSBL lookup had not succeeded, i.e. the host is + not on the list. */ + + if (invert_result != (da == NULL)) + { + HDEBUG(D_dnsbl) + { + debug_printf("=> but we are not accepting this block class because\n"); + debug_printf("=> there was %s match for %c%s\n", + invert_result? "an exclude":"no", bitmask? '&' : '=', iplist); + } + continue; /* With next DNSBL domain */ + } + } + + /* Either there was no IP list, or the record matched. Look up a TXT record + if it hasn't previously been done. */ + + if (!cb->text_set) + { + cb->text_set = TRUE; + if (dns_basic_lookup(&dnsa, query, T_TXT) == DNS_SUCCEED) + { + dns_record *rr; + for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); + rr != NULL; + rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) + if (rr->type == T_TXT) break; + if (rr != NULL) + { + int len = (rr->data)[0]; + if (len > 511) len = 127; + store_pool = POOL_PERM; + cb->text = string_sprintf("%.*s", len, (const uschar *)(rr->data+1)); + store_pool = old_pool; + } + } + } + + HDEBUG(D_dnsbl) + { + debug_printf("=> that means %s is listed at %s\n", + (key == NULL)? sender_host_address : key, domain); + } + + dnslist_domain = string_copy(domain); + dnslist_value = addlist; + dnslist_text = cb->text; + return OK; + } + + /* There was a problem with the DNS lookup */ + + if (cb->rc != DNS_NOMATCH && cb->rc != DNS_NODATA) + { + log_write(L_dnslist_defer, LOG_MAIN, + "DNS list lookup defer (probably timeout) for %s: %s", query, + (defer_return == OK)? US"assumed in list" : + (defer_return == FAIL)? US"assumed not in list" : + US"returned DEFER"); + return defer_return; + } + + /* No entry was found in the DNS; continue for next domain */ + + HDEBUG(D_dnsbl) + { + debug_printf("DNS lookup for %s failed\n", query); + debug_printf("=> that means %s is not listed at %s\n", + (key == NULL)? sender_host_address : key, domain); + } + } /* Continue with next domain */ + +return FAIL; +} + +/* End of verify.c */ |