X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/7cd171b76e5bd3cb825c2a8720bc1fe4ad9b37e0..6259ba7148cd408d4704850c206dfc2248d2d1cc:/src/src/routers/dnslookup.c diff --git a/src/src/routers/dnslookup.c b/src/src/routers/dnslookup.c index b4ad5eafd..807191b91 100644 --- a/src/src/routers/dnslookup.c +++ b/src/src/routers/dnslookup.c @@ -2,7 +2,8 @@ * Exim - an Internet mail transport agent * *************************************************/ -/* Copyright (c) University of Cambridge 1995 - 2009 */ +/* Copyright (c) University of Cambridge 1995 - 2018 */ +/* Copyright (c) The Exim Maintainers 2020 - 2021 */ /* See the file NOTICE for conditions of use and distribution. */ #include "../exim.h" @@ -12,30 +13,22 @@ /* Options specific to the dnslookup router. */ +#define LOFF(field) OPT_OFF(dnslookup_router_options_block, field) optionlist dnslookup_router_options[] = { - { "check_secondary_mx", opt_bool, - (void *)(offsetof(dnslookup_router_options_block, check_secondary_mx)) }, - { "check_srv", opt_stringptr, - (void *)(offsetof(dnslookup_router_options_block, check_srv)) }, - { "fail_defer_domains", opt_stringptr, - (void *)(offsetof(dnslookup_router_options_block, fail_defer_domains)) }, - { "mx_domains", opt_stringptr, - (void *)(offsetof(dnslookup_router_options_block, mx_domains)) }, - { "mx_fail_domains", opt_stringptr, - (void *)(offsetof(dnslookup_router_options_block, mx_fail_domains)) }, - { "qualify_single", opt_bool, - (void *)(offsetof(dnslookup_router_options_block, qualify_single)) }, - { "rewrite_headers", opt_bool, - (void *)(offsetof(dnslookup_router_options_block, rewrite_headers)) }, - { "same_domain_copy_routing", opt_bool|opt_public, - (void *)(offsetof(router_instance, same_domain_copy_routing)) }, - { "search_parents", opt_bool, - (void *)(offsetof(dnslookup_router_options_block, search_parents)) }, - { "srv_fail_domains", opt_stringptr, - (void *)(offsetof(dnslookup_router_options_block, srv_fail_domains)) }, - { "widen_domains", opt_stringptr, - (void *)(offsetof(dnslookup_router_options_block, widen_domains)) } + { "check_secondary_mx", opt_bool, LOFF(check_secondary_mx) }, + { "check_srv", opt_stringptr, LOFF(check_srv) }, + { "fail_defer_domains", opt_stringptr, LOFF(fail_defer_domains) }, + { "ipv4_only", opt_stringptr, LOFF(ipv4_only) }, + { "ipv4_prefer", opt_stringptr, LOFF(ipv4_prefer) }, + { "mx_domains", opt_stringptr, LOFF(mx_domains) }, + { "mx_fail_domains", opt_stringptr, LOFF(mx_fail_domains) }, + { "qualify_single", opt_bool, LOFF(qualify_single) }, + { "rewrite_headers", opt_bool, LOFF(rewrite_headers) }, + { "same_domain_copy_routing", opt_bool|opt_public, OPT_OFF(router_instance, same_domain_copy_routing) }, + { "search_parents", opt_bool, LOFF(search_parents) }, + { "srv_fail_domains", opt_stringptr, LOFF(srv_fail_domains) }, + { "widen_domains", opt_stringptr, LOFF(widen_domains) } }; /* Size of the options list. An extern variable has to be used so that its @@ -44,19 +37,37 @@ address can appear in the tables drtables.c. */ int dnslookup_router_options_count = sizeof(dnslookup_router_options)/sizeof(optionlist); + +#ifdef MACRO_PREDEF + +/* Dummy entries */ +dnslookup_router_options_block dnslookup_router_option_defaults = {0}; +void dnslookup_router_init(router_instance *rblock) {} +int dnslookup_router_entry(router_instance *rblock, address_item *addr, + struct passwd *pw, int verify, address_item **addr_local, + address_item **addr_remote, address_item **addr_new, + address_item **addr_succeed) {return 0;} + +#else /*!MACRO_PREDEF*/ + + + + /* Default private options block for the dnslookup router. */ dnslookup_router_options_block dnslookup_router_option_defaults = { - FALSE, /* check_secondary_mx */ - TRUE, /* qualify_single */ - FALSE, /* search_parents */ - TRUE, /* rewrite_headers */ - NULL, /* widen_domains */ - NULL, /* mx_domains */ - NULL, /* mx_fail_domains */ - NULL, /* srv_fail_domains */ - NULL, /* check_srv */ - NULL /* fail_defer_domains */ + .check_secondary_mx = FALSE, + .qualify_single = TRUE, + .search_parents = FALSE, + .rewrite_headers = TRUE, + .widen_domains = NULL, + .mx_domains = NULL, + .mx_fail_domains = NULL, + .srv_fail_domains = NULL, + .check_srv = NULL, + .fail_defer_domains = NULL, + .ipv4_only = NULL, + .ipv4_prefer = NULL, }; @@ -138,7 +149,7 @@ dnslookup_router_entry( host_item h; int rc; int widen_sep = 0; -int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A; +int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A | HOST_FIND_BY_AAAA; dnslookup_router_options_block *ob = (dnslookup_router_options_block *)(rblock->options_block); uschar *srv_service = NULL; @@ -149,9 +160,6 @@ const uschar *fully_qualified_name; const uschar *listptr; uschar widen_buffer[256]; -addr_new = addr_new; /* Keep picky compilers happy */ -addr_succeed = addr_succeed; - DEBUG(D_route) debug_printf("%s router called for %s\n domain = %s\n", rblock->name, addr->address, addr->domain); @@ -161,7 +169,7 @@ DEBUG(D_route) if (ob->check_srv) { if ( !(srv_service = expand_string(ob->check_srv)) - && !expand_string_forcedfail) + && !f.expand_string_forcedfail) { addr->message = string_sprintf("%s router: failed to expand \"%s\": %s", rblock->name, ob->check_srv, expand_string_message); @@ -196,6 +204,7 @@ if ( ob->widen_domains && (verify != v_sender || !ob->rewrite_headers || addr->parent)) { listptr = ob->widen_domains; + /* not expanded so should never be tainted */ widen = string_nextinlist(&listptr, &widen_sep, widen_buffer, sizeof(widen_buffer)); @@ -225,6 +234,7 @@ for (;;) else if (widen) { h.name = string_sprintf("%s.%s", addr->domain, widen); + /* not expanded so should never be tainted */ widen = string_nextinlist(&listptr, &widen_sep, widen_buffer, sizeof(widen_buffer)); DEBUG(D_route) debug_printf("%s router widened %s to %s\n", rblock->name, @@ -239,6 +249,19 @@ for (;;) } else return DECLINE; + /* Check if we must request only. or prefer, ipv4 */ + + if ( ob->ipv4_only + && expand_check_condition(ob->ipv4_only, rblock->name, US"router")) + flags = flags & ~HOST_FIND_BY_AAAA | HOST_FIND_IPV4_ONLY; + else if (f.search_find_defer) + return DEFER; + if ( ob->ipv4_prefer + && expand_check_condition(ob->ipv4_prefer, rblock->name, US"router")) + flags |= HOST_FIND_IPV4_FIRST; + else if (f.search_find_defer) + return DEFER; + /* Set up the rest of the initial host item. Others may get chained on if there is more than one IP address. We set it up here instead of outside the loop so as to re-initialize if a previous try succeeded but was rejected @@ -263,9 +286,11 @@ for (;;) if (ob->search_parents) flags |= HOST_FIND_SEARCH_PARENTS; } - rc = host_find_bydns(&h, CUS rblock->ignore_target_hosts, flags, srv_service, - ob->srv_fail_domains, ob->mx_fail_domains, - &rblock->dnssec, &fully_qualified_name, &removed); + rc = host_find_bydns(&h, CUS rblock->ignore_target_hosts, flags, + srv_service, ob->srv_fail_domains, ob->mx_fail_domains, + &rblock->dnssec, + &fully_qualified_name, &removed); + if (removed) setflag(addr, af_local_host_removed); /* If host found with only address records, test for the domain's being in @@ -291,6 +316,11 @@ for (;;) /* Deferral returns forthwith, and anything other than failure breaks the loop. */ + if (rc == HOST_FIND_SECURITY) + { + addr->message = US"host lookup done insecurely"; + return DEFER; + } if (rc == HOST_FIND_AGAIN) { if (rblock->pass_on_timeout) @@ -305,6 +335,22 @@ for (;;) if (rc != HOST_FIND_FAILED) break; + if (ob->fail_defer_domains) + switch(match_isinlist(fully_qualified_name, + CUSS &ob->fail_defer_domains, 0, + &domainlist_anchor, addr->domain_cache, MCL_DOMAIN, TRUE, NULL)) + { + case DEFER: + addr->message = US"lookup defer for fail_defer_domains option"; + return DEFER; + + case OK: + DEBUG(D_route) debug_printf("%s router: matched fail_defer_domains\n", + rblock->name); + addr->message = US"missing MX, or all MXs point to missing A records," + " and defer requested"; + return DEFER; + } /* Check to see if the failure is the result of MX records pointing to non-existent domains, and if so, set an appropriate error message; the case of an MX or SRV record pointing to "." is another special case that we can @@ -335,29 +381,13 @@ for (;;) addr->message); } } - if (ob->fail_defer_domains) - { - switch(match_isinlist(fully_qualified_name, - CUSS &ob->fail_defer_domains, 0, - &domainlist_anchor, addr->domain_cache, MCL_DOMAIN, TRUE, NULL)) - { - case DEFER: - addr->message = US"lookup defer for fail_defer_domains"; - return DEFER; - - case OK: - DEBUG(D_route) debug_printf("%s router: matched fail_defer_domains\n", - rblock->name); - return DEFER; - } - } return DECLINE; } /* If there's a syntax error, do not continue with any widening, and note the error. */ - if (host_find_failed_syntax) + if (f.host_find_failed_syntax) { addr->message = string_sprintf("mail domain \"%s\" is syntactically " "invalid", h.name); @@ -417,7 +447,7 @@ else if (ob->check_secondary_mx && !testflag(addr, af_local_host_removed)) rc = rf_get_errors_address(addr, rblock, verify, &addr->prop.errors_address); if (rc != OK) return rc; -/* Set up the additional and removeable headers for this address. */ +/* Set up the additional and removable headers for this address. */ rc = rf_get_munge_headers(addr, rblock, &addr->prop.extra_headers, &addr->prop.remove_headers); @@ -426,7 +456,7 @@ if (rc != OK) return rc; /* Get store in which to preserve the original host item, chained on to the address. */ -addr->host_list = store_get(sizeof(host_item)); +addr->host_list = store_get(sizeof(host_item), GET_UNTAINTED); addr->host_list[0] = h; /* Fill in the transport and queue the address for delivery. */ @@ -441,6 +471,7 @@ return rf_queue_add(addr, addr_local, addr_remote, rblock, pw)? OK : DEFER; } +#endif /*!MACRO_PREDEF*/ /* End of routers/dnslookup.c */ /* vi: aw ai sw=2 */