X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/0f06b4f296802e4e13188c740ea09419931a3020..0de9945258c2e7910c35f715caf07c5e9270aa1b:/src/src/host.c diff --git a/src/src/host.c b/src/src/host.c index 2eef0ba70..0e0e0130b 100644 --- a/src/src/host.c +++ b/src/src/host.c @@ -2,7 +2,8 @@ * Exim - an Internet mail transport agent * *************************************************/ -/* Copyright (c) University of Cambridge 1995 - 2012 */ +/* Copyright (c) University of Cambridge 1995 - 2018 */ +/* Copyright (c) The Exim Maintainers 2020 */ /* See the file NOTICE for conditions of use and distribution. */ /* Functions for finding hosts, either by gethostbyname(), gethostbyaddr(), or @@ -84,7 +85,7 @@ if (limit < 1) return 0; if (random_seed == 0) { - if (running_in_test_harness) random_seed = 42; else + if (f.running_in_test_harness) random_seed = 42; else { int p = (int)getpid(); random_seed = (int)time(NULL) ^ ((p << 16) | p); @@ -94,6 +95,53 @@ random_seed = 1103515245 * random_seed + 12345; return (unsigned int)(random_seed >> 16) % limit; } +/************************************************* +* Wrappers for logging lookup times * +*************************************************/ + +/* When the 'slow_lookup_log' variable is enabled, these wrappers will +write to the log file all (potential) dns lookups that take more than +slow_lookup_log milliseconds +*/ + +static void +log_long_lookup(const uschar * type, const uschar * data, unsigned long msec) +{ +log_write(0, LOG_MAIN, "Long %s lookup for '%s': %lu msec", + type, data, msec); +} + + +/* returns the current system epoch time in milliseconds. */ +static unsigned long +get_time_in_ms() +{ +struct timeval tmp_time; +unsigned long seconds, microseconds; + +gettimeofday(&tmp_time, NULL); +seconds = (unsigned long) tmp_time.tv_sec; +microseconds = (unsigned long) tmp_time.tv_usec; +return seconds*1000 + microseconds/1000; +} + + +static int +dns_lookup_timerwrap(dns_answer *dnsa, const uschar *name, int type, + const uschar **fully_qualified_name) +{ +int retval; +unsigned long time_msec; + +if (!slow_lookup_log) + return dns_lookup(dnsa, name, type, fully_qualified_name); + +time_msec = get_time_in_ms(); +retval = dns_lookup(dnsa, name, type, fully_qualified_name); +if ((time_msec = get_time_in_ms() - time_msec) > slow_lookup_log) + log_long_lookup(dns_text_type(type), name, time_msec); +return retval; +} /************************************************* @@ -101,8 +149,7 @@ return (unsigned int)(random_seed >> 16) % limit; *************************************************/ /* This function is called instead of gethostbyname(), gethostbyname2(), or -getipnodebyname() when running in the test harness. It recognizes the name -"manyhome.test.ex" and generates a humungous number of IP addresses. It also +getipnodebyname() when running in the test harness. . It also recognizes an unqualified "localhost" and forces it to the appropriate loopback address. IP addresses are treated as literals. For other names, it uses the DNS to find the host name. In the test harness, this means it will access only the @@ -118,7 +165,7 @@ Returns: a hostent structure or NULL for an error */ static struct hostent * -host_fake_gethostbyname(uschar *name, int af, int *error_num) +host_fake_gethostbyname(const uschar *name, int af, int *error_num) { #if HAVE_IPV6 int alen = (af == AF_INET)? sizeof(struct in_addr):sizeof(struct in6_addr); @@ -127,72 +174,39 @@ int alen = sizeof(struct in_addr); #endif int ipa; -uschar *lname = name; +const uschar *lname = name; uschar *adds; uschar **alist; struct hostent *yield; -dns_answer dnsa; +dns_answer * dnsa = store_get_dns_answer(); dns_scan dnss; -dns_record *rr; DEBUG(D_host_lookup) debug_printf("using host_fake_gethostbyname for %s (%s)\n", name, - (af == AF_INET)? "IPv4" : "IPv6"); - -/* Handle the name that needs a vast number of IP addresses */ - -if (Ustrcmp(name, "manyhome.test.ex") == 0 && af == AF_INET) - { - int i, j; - yield = store_get(sizeof(struct hostent)); - alist = store_get(2049 * sizeof(char *)); - adds = store_get(2048 * alen); - yield->h_name = CS name; - yield->h_aliases = NULL; - yield->h_addrtype = af; - yield->h_length = alen; - yield->h_addr_list = CSS alist; - for (i = 104; i <= 111; i++) - { - for (j = 0; j <= 255; j++) - { - *alist++ = adds; - *adds++ = 10; - *adds++ = 250; - *adds++ = i; - *adds++ = j; - } - } - *alist = NULL; - return yield; - } + af == AF_INET ? "IPv4" : "IPv6"); /* Handle unqualified "localhost" */ if (Ustrcmp(name, "localhost") == 0) - lname = (af == AF_INET)? US"127.0.0.1" : US"::1"; + lname = af == AF_INET ? US"127.0.0.1" : US"::1"; /* Handle a literal IP address */ -ipa = string_is_ip_address(lname, NULL); -if (ipa != 0) - { - if ((ipa == 4 && af == AF_INET) || - (ipa == 6 && af == AF_INET6)) +if ((ipa = string_is_ip_address(lname, NULL)) != 0) + if ( ipa == 4 && af == AF_INET + || ipa == 6 && af == AF_INET6) { - int i, n; int x[4]; - yield = store_get(sizeof(struct hostent)); - alist = store_get(2 * sizeof(char *)); - adds = store_get(alen); + yield = store_get(sizeof(struct hostent), FALSE); + alist = store_get(2 * sizeof(char *), FALSE); + adds = store_get(alen, FALSE); yield->h_name = CS name; yield->h_aliases = NULL; yield->h_addrtype = af; yield->h_length = alen; yield->h_addr_list = CSS alist; *alist++ = adds; - n = host_aton(lname, x); - for (i = 0; i < n; i++) + for (int n = host_aton(lname, x), i = 0; i < n; i++) { int y = x[i]; *adds++ = (y >> 24) & 255; @@ -210,14 +224,13 @@ if (ipa != 0) *error_num = HOST_NOT_FOUND; return NULL; } - } /* Handle a host name */ else { - int type = (af == AF_INET)? T_A:T_AAAA; - int rc = dns_lookup(&dnsa, lname, type, NULL); + int type = af == AF_INET ? T_A:T_AAAA; + int rc = dns_lookup_timerwrap(dnsa, lname, type, NULL); int count = 0; lookup_dnssec_authenticated = NULL; @@ -232,16 +245,14 @@ else case DNS_FAIL: *error_num = NO_RECOVERY; return NULL; } - for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); - rr != NULL; - rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) - { - if (rr->type == type) count++; - } + for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); + rr; + rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == type) + count++; - yield = store_get(sizeof(struct hostent)); - alist = store_get((count + 1) * sizeof(char **)); - adds = store_get(count *alen); + yield = store_get(sizeof(struct hostent), FALSE); + alist = store_get((count + 1) * sizeof(char *), FALSE); + adds = store_get(count *alen, FALSE); yield->h_name = CS name; yield->h_aliases = NULL; @@ -249,18 +260,15 @@ else yield->h_length = alen; yield->h_addr_list = CSS alist; - for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); - rr != NULL; - rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) + for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); + rr; + rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == type) { - int i, n; int x[4]; dns_address *da; - if (rr->type != type) continue; - da = dns_address_from_rr(&dnsa, rr); + if (!(da = dns_address_from_rr(dnsa, rr))) break; *alist++ = adds; - n = host_aton(da->address, x); - for (i = 0; i < n; i++) + for (int n = host_aton(da->address, x), i = 0; i < n; i++) { int y = x[i]; *adds++ = (y >> 24) & 255; @@ -295,19 +303,18 @@ Returns: nothing */ void -host_build_hostlist(host_item **anchor, uschar *list, BOOL randomize) +host_build_hostlist(host_item **anchor, const uschar *list, BOOL randomize) { int sep = 0; int fake_mx = MX_NONE; /* This value is actually -1 */ uschar *name; -uschar buffer[1024]; -if (list == NULL) return; +if (!list) return; if (randomize) fake_mx--; /* Start at -2 for randomizing */ *anchor = NULL; -while ((name = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) +while ((name = string_nextinlist(&list, &sep, NULL, 0))) { host_item *h; @@ -317,8 +324,8 @@ while ((name = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) continue; } - h = store_get(sizeof(host_item)); - h->name = string_copy(name); + h = store_get(sizeof(host_item), FALSE); + h->name = name; h->address = NULL; h->port = PORT_NONE; h->mx = fake_mx; @@ -327,7 +334,7 @@ while ((name = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) h->why = hwhy_unknown; h->last_try = 0; - if (*anchor == NULL) + if (!*anchor) { h->next = NULL; *anchor = h; @@ -342,7 +349,7 @@ while ((name = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) } else { - while (hh->next != NULL && h->sort_key >= (hh->next)->sort_key) + while (hh->next && h->sort_key >= hh->next->sort_key) hh = hh->next; h->next = hh->next; hh->next = h; @@ -444,7 +451,7 @@ Returns: a port number or PORT_NONE int host_item_get_port(host_item *h) { -uschar *p; +const uschar *p; int port, x; int len = Ustrlen(h->name); @@ -504,7 +511,9 @@ There wouldn't be two different variables if I had got all this right in the first place. Because this data may survive over more than one incoming SMTP message, it has -to be in permanent store. +to be in permanent store. However, STARTTLS has to be forgotten and redone +on a multi-message conn, so this will be called once per message then. Hence +we use malloc, so we can free. Arguments: none Returns: nothing @@ -514,13 +523,13 @@ void host_build_sender_fullhost(void) { BOOL show_helo = TRUE; -uschar *address; +uschar * address, * fullhost, * rcvhost; +rmark reset_point; int len; -int old_pool = store_pool; -if (sender_host_address == NULL) return; +if (!sender_host_address) return; -store_pool = POOL_PERM; +reset_point = store_mark(); /* Set up address, with or without the port. After discussion, it seems that the only format that doesn't cause trouble is [aaaa]:pppp. However, we can't @@ -528,17 +537,17 @@ use this directly as the first item for Received: because it ain't an RFC 2822 domain. Sigh. */ address = string_sprintf("[%s]:%d", sender_host_address, sender_host_port); -if ((log_extra_selector & LX_incoming_port) == 0 || sender_host_port <= 0) +if (!LOGGING(incoming_port) || sender_host_port <= 0) *(Ustrrchr(address, ':')) = 0; /* If there's no EHLO/HELO data, we can't show it. */ -if (sender_helo_name == NULL) show_helo = FALSE; +if (!sender_helo_name) show_helo = FALSE; /* If HELO/EHLO was followed by an IP literal, it's messy because of two features of IPv6. Firstly, there's the "IPv6:" prefix (Exim is liberal and doesn't require this, for historical reasons). Secondly, IPv6 addresses may not -be given in canonical form, so we have to canonicize them before comparing. As +be given in canonical form, so we have to canonicalize them before comparing. As it happens, the code works for both IPv4 and IPv6. */ else if (sender_helo_name[0] == '[' && @@ -570,46 +579,40 @@ else if (sender_helo_name[0] == '[' && /* Host name is not verified */ -if (sender_host_name == NULL) +if (!sender_host_name) { uschar *portptr = Ustrstr(address, "]:"); - int size = 0; - int ptr = 0; + gstring * g; int adlen; /* Sun compiler doesn't like ++ in initializers */ - adlen = (portptr == NULL)? Ustrlen(address) : (++portptr - address); - sender_fullhost = (sender_helo_name == NULL)? address : - string_sprintf("(%s) %s", sender_helo_name, address); + adlen = portptr ? (++portptr - address) : Ustrlen(address); + fullhost = sender_helo_name + ? string_sprintf("(%s) %s", sender_helo_name, address) + : address; - sender_rcvhost = string_cat(NULL, &size, &ptr, address, adlen); + g = string_catn(NULL, address, adlen); - if (sender_ident != NULL || show_helo || portptr != NULL) + if (sender_ident || show_helo || portptr) { int firstptr; - sender_rcvhost = string_cat(sender_rcvhost, &size, &ptr, US" (", 2); - firstptr = ptr; + g = string_catn(g, US" (", 2); + firstptr = g->ptr; - if (portptr != NULL) - sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2, US"port=", - portptr + 1); + if (portptr) + g = string_append(g, 2, US"port=", portptr + 1); if (show_helo) - sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2, - (firstptr == ptr)? US"helo=" : US" helo=", sender_helo_name); + g = string_append(g, 2, + firstptr == g->ptr ? US"helo=" : US" helo=", sender_helo_name); - if (sender_ident != NULL) - sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2, - (firstptr == ptr)? US"ident=" : US" ident=", sender_ident); + if (sender_ident) + g = string_append(g, 2, + firstptr == g->ptr ? US"ident=" : US" ident=", sender_ident); - sender_rcvhost = string_cat(sender_rcvhost, &size, &ptr, US")", 1); + g = string_catn(g, US")", 1); } - sender_rcvhost[ptr] = 0; /* string_cat() always leaves room */ - - /* Release store, because string_cat allocated a minimum of 100 bytes that - are rarely completely used. */ - - store_reset(sender_rcvhost + ptr + 1); + rcvhost = string_from_gstring(g); } /* Host name is known and verified. Unless we've already found that the HELO @@ -622,25 +625,28 @@ else if (show_helo) { - sender_fullhost = string_sprintf("%s (%s) %s", sender_host_name, + fullhost = string_sprintf("%s (%s) %s", sender_host_name, sender_helo_name, address); - sender_rcvhost = (sender_ident == NULL)? - string_sprintf("%s (%s helo=%s)", sender_host_name, - address, sender_helo_name) : - string_sprintf("%s\n\t(%s helo=%s ident=%s)", sender_host_name, - address, sender_helo_name, sender_ident); + rcvhost = sender_ident + ? string_sprintf("%s\n\t(%s helo=%s ident=%s)", sender_host_name, + address, sender_helo_name, sender_ident) + : string_sprintf("%s (%s helo=%s)", sender_host_name, + address, sender_helo_name); } else { - sender_fullhost = string_sprintf("%s %s", sender_host_name, address); - sender_rcvhost = (sender_ident == NULL)? - string_sprintf("%s (%s)", sender_host_name, address) : - string_sprintf("%s (%s ident=%s)", sender_host_name, address, - sender_ident); + fullhost = string_sprintf("%s %s", sender_host_name, address); + rcvhost = sender_ident + ? string_sprintf("%s (%s ident=%s)", sender_host_name, address, + sender_ident) + : string_sprintf("%s (%s)", sender_host_name, address); } } -store_pool = old_pool; +sender_fullhost = string_copy_perm(fullhost, TRUE); +sender_rcvhost = string_copy_perm(rcvhost, TRUE); + +store_reset(reset_point); DEBUG(D_host_lookup) debug_printf("sender_fullhost = %s\n", sender_fullhost); DEBUG(D_host_lookup) debug_printf("sender_rcvhost = %s\n", sender_rcvhost); @@ -660,6 +666,8 @@ return depends on whether sender_fullhost and sender_ident are set or not: ident set, no host => U=ident ident set, host set => H=sender_fullhost U=ident +Use taint-unchecked routines on the assumption we'll never expand the results. + Arguments: useflag TRUE if first item to be flagged (H= or U=); if there are two items, the second is always flagged @@ -670,24 +678,21 @@ Returns: pointer to a string in big_buffer uschar * host_and_ident(BOOL useflag) { -if (sender_fullhost == NULL) - { - (void)string_format(big_buffer, big_buffer_size, "%s%s", useflag? "U=" : "", - (sender_ident == NULL)? US"unknown" : sender_ident); - } +if (!sender_fullhost) + string_format_nt(big_buffer, big_buffer_size, "%s%s", useflag ? "U=" : "", + sender_ident ? sender_ident : US"unknown"); else { - uschar *flag = useflag? US"H=" : US""; - uschar *iface = US""; - if ((log_extra_selector & LX_incoming_interface) != 0 && - interface_address != NULL) + uschar * flag = useflag ? US"H=" : US""; + uschar * iface = US""; + if (LOGGING(incoming_interface) && interface_address) iface = string_sprintf(" I=[%s]:%d", interface_address, interface_port); - if (sender_ident == NULL) - (void)string_format(big_buffer, big_buffer_size, "%s%s%s", - flag, sender_fullhost, iface); - else - (void)string_format(big_buffer, big_buffer_size, "%s%s%s U=%s", + if (sender_ident) + string_format_nt(big_buffer, big_buffer_size, "%s%s%s U=%s", flag, sender_fullhost, iface, sender_ident); + else + string_format_nt(big_buffer, big_buffer_size, "%s%s%s", + flag, sender_fullhost, iface); } return big_buffer; } @@ -718,20 +723,19 @@ Returns: a chain of ip_address_items, each containing to a textual */ ip_address_item * -host_build_ifacelist(uschar *list, uschar *name) +host_build_ifacelist(const uschar *list, uschar *name) { int sep = 0; uschar *s; -uschar buffer[64]; -ip_address_item *yield = NULL; -ip_address_item *last = NULL; -ip_address_item *next; +ip_address_item * yield = NULL, * last = NULL, * next; +BOOL taint = is_tainted(list); -while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) +while ((s = string_nextinlist(&list, &sep, NULL, 0))) { int ipv; int port = host_address_extract_port(s); /* Leaves just the IP address */ - if ((ipv = string_is_ip_address(s, NULL)) == 0) + + if (!(ipv = string_is_ip_address(s, NULL))) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Malformed IP address \"%s\" in %s", s, name); @@ -743,13 +747,16 @@ while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) address above. The field in the ip_address_item is large enough to hold an IPv6 address. */ - next = store_get(sizeof(ip_address_item)); + next = store_get(sizeof(ip_address_item), taint); next->next = NULL; Ustrcpy(next->address, s); next->port = port; next->v6_include_v4 = FALSE; + next->log = NULL; - if (yield == NULL) yield = last = next; else + if (!yield) + yield = last = next; + else { last->next = next; last = next; @@ -792,9 +799,9 @@ static ip_address_item * add_unique_interface(ip_address_item *list, ip_address_item *ipa) { ip_address_item *ipa2; -for (ipa2 = list; ipa2 != NULL; ipa2 = ipa2->next) +for (ipa2 = list; ipa2; ipa2 = ipa2->next) if (Ustrcmp(ipa2->address, ipa->address) == 0) return list; -ipa2 = store_get_perm(sizeof(ip_address_item)); +ipa2 = store_get_perm(sizeof(ip_address_item), FALSE); *ipa2 = *ipa; ipa2->next = list; return ipa2; @@ -810,34 +817,32 @@ ip_address_item *running_interfaces = NULL; if (local_interface_data == NULL) { - void *reset_item = store_get(0); - ip_address_item *dlist = host_build_ifacelist(local_interfaces, + void *reset_item = store_mark(); + ip_address_item *dlist = host_build_ifacelist(CUS local_interfaces, US"local_interfaces"); - ip_address_item *xlist = host_build_ifacelist(extra_local_interfaces, + ip_address_item *xlist = host_build_ifacelist(CUS extra_local_interfaces, US"extra_local_interfaces"); ip_address_item *ipa; - if (dlist == NULL) dlist = xlist; else + if (!dlist) dlist = xlist; + else { - for (ipa = dlist; ipa->next != NULL; ipa = ipa->next); + for (ipa = dlist; ipa->next; ipa = ipa->next) ; ipa->next = xlist; } - for (ipa = dlist; ipa != NULL; ipa = ipa->next) + for (ipa = dlist; ipa; ipa = ipa->next) { if (Ustrcmp(ipa->address, "0.0.0.0") == 0 || Ustrcmp(ipa->address, "::0") == 0) { - ip_address_item *ipa2; BOOL ipv6 = ipa->address[0] == ':'; - if (running_interfaces == NULL) + if (!running_interfaces) running_interfaces = os_find_running_interfaces(); - for (ipa2 = running_interfaces; ipa2 != NULL; ipa2 = ipa2->next) - { + for (ip_address_item * ipa2 = running_interfaces; ipa2; ipa2 = ipa2->next) if ((Ustrchr(ipa2->address, ':') != NULL) == ipv6) local_interface_data = add_unique_interface(local_interface_data, - ipa2); - } + ipa2); } else { @@ -904,21 +909,21 @@ if (type < 0) if (family == AF_INET6) { struct sockaddr_in6 *sk = (struct sockaddr_in6 *)arg; - yield = (uschar *)inet_ntop(family, &(sk->sin6_addr), CS addr_buffer, + yield = US inet_ntop(family, &(sk->sin6_addr), CS addr_buffer, sizeof(addr_buffer)); if (portptr != NULL) *portptr = ntohs(sk->sin6_port); } else { struct sockaddr_in *sk = (struct sockaddr_in *)arg; - yield = (uschar *)inet_ntop(family, &(sk->sin_addr), CS addr_buffer, + yield = US inet_ntop(family, &(sk->sin_addr), CS addr_buffer, sizeof(addr_buffer)); if (portptr != NULL) *portptr = ntohs(sk->sin_port); } } else { - yield = (uschar *)inet_ntop(type, arg, CS addr_buffer, sizeof(addr_buffer)); + yield = US inet_ntop(type, arg, CS addr_buffer, sizeof(addr_buffer)); } /* If the result is a mapped IPv4 address, show it in V4 format. */ @@ -940,13 +945,15 @@ else /* If there is no buffer, put the string into some new store. */ -if (buffer == NULL) return string_copy(yield); +if (!buffer) buffer = store_get(46, FALSE); /* Callers of this function with a non-NULL buffer must ensure that it is large enough to hold an IPv6 address, namely, at least 46 bytes. That's what -makes this use of strcpy() OK. */ +makes this use of strcpy() OK. +If the library returned apparently an apparently tainted string, clean it; +we trust IP addresses. */ -Ustrcpy(buffer, yield); +string_format_nt(buffer, 46, "%s", yield); return buffer; } @@ -972,7 +979,7 @@ Returns: the number of ints used */ int -host_aton(uschar *address, int *bin) +host_aton(const uschar *address, int *bin) { int x[4]; int v4offset = 0; @@ -984,8 +991,8 @@ supported. */ if (Ustrchr(address, ':') != NULL) { - uschar *p = address; - uschar *component[8]; + const uschar *p = address; + const uschar *component[8]; BOOL ipv4_ends = FALSE; int ci = 0; int nulloffset = 0; @@ -1052,7 +1059,7 @@ if (Ustrchr(address, ':') != NULL) /* Handle IPv4 address */ (void)sscanf(CS address, "%d.%d.%d.%d", x, x+1, x+2, x+3); -bin[v4offset] = (x[0] << 24) + (x[1] << 16) + (x[2] << 8) + x[3]; +bin[v4offset] = ((uint)x[0] << 24) + (x[1] << 16) + (x[2] << 8) + x[3]; return v4offset+1; } @@ -1075,15 +1082,14 @@ Returns: nothing void host_mask(int count, int *binary, int mask) { -int i; if (mask < 0) mask = 99999; -for (i = 0; i < count; i++) +for (int i = 0; i < count; i++) { int wordmask; if (mask == 0) wordmask = 0; else if (mask < 32) { - wordmask = (-1) << (32 - mask); + wordmask = (uint)(-1) << (32 - mask); mask = 0; } else @@ -1124,42 +1130,90 @@ Returns: the number of characters placed in buffer, not counting int host_nmtoa(int count, int *binary, int mask, uschar *buffer, int sep) { -int i, j; +int j; uschar *tt = buffer; if (count == 1) { j = binary[0]; - for (i = 24; i >= 0; i -= 8) - { - sprintf(CS tt, "%d.", (j >> i) & 255); - while (*tt) tt++; - } + for (int i = 24; i >= 0; i -= 8) + tt += sprintf(CS tt, "%d.", (j >> i) & 255); } else - { - for (i = 0; i < 4; i++) + for (int i = 0; i < 4; i++) { j = binary[i]; - sprintf(CS tt, "%04x%c%04x%c", (j >> 16) & 0xffff, sep, j & 0xffff, sep); - while (*tt) tt++; + tt += sprintf(CS tt, "%04x%c%04x%c", (j >> 16) & 0xffff, sep, j & 0xffff, sep); } - } tt--; /* lose final separator */ if (mask < 0) *tt = 0; else - { - sprintf(CS tt, "/%d", mask); - while (*tt) tt++; - } + tt += sprintf(CS tt, "/%d", mask); return tt - buffer; } +/* Like host_nmtoa() but: ipv6-only, canonical output, no mask + +Arguments: + binary points to the ints + buffer big enough to hold the result + +Returns: the number of characters placed in buffer, not counting + the final nul. +*/ + +int +ipv6_nmtoa(int * binary, uschar * buffer) +{ +int i, j, k; +uschar * c = buffer; +uschar * d = NULL; /* shut insufficiently "clever" compiler up */ + +for (i = 0; i < 4; i++) + { /* expand to text */ + j = binary[i]; + c += sprintf(CS c, "%x:%x:", (j >> 16) & 0xffff, j & 0xffff); + } + +for (c = buffer, k = -1, i = 0; i < 8; i++) + { /* find longest 0-group sequence */ + if (*c == '0') /* must be "0:" */ + { + uschar * s = c; + j = i; + while (c[2] == '0') i++, c += 2; + if (i-j > k) + { + k = i-j; /* length of sequence */ + d = s; /* start of sequence */ + } + } + while (*++c != ':') ; + c++; + } + +c[-1] = '\0'; /* drop trailing colon */ + +/* debug_printf("%s: D k %d <%s> <%s>\n", __FUNCTION__, k, d, d + 2*(k+1)); */ +if (k >= 0) + { /* collapse */ + c = d + 2*(k+1); + if (d == buffer) c--; /* need extra colon */ + *d++ = ':'; /* 1st 0 */ + while ((*d++ = *c++)) ; + } +else + d = c; + +return d - buffer; +} + + /************************************************* * Check port for tls_on_connect * @@ -1179,7 +1233,7 @@ host_is_tls_on_connect_port(int port) { int sep = 0; uschar buffer[32]; -uschar *list = tls_in.on_connect_ports; +const uschar *list = tls_in.on_connect_ports; uschar *s; uschar *end; @@ -1214,9 +1268,8 @@ Returns: */ BOOL -host_is_in_net(uschar *host, uschar *net, int maskoffset) +host_is_in_net(const uschar *host, const uschar *net, int maskoffset) { -int i; int address[4]; int incoming[4]; int mlen; @@ -1249,13 +1302,13 @@ if (insize != size) return FALSE; /* Else do the masked comparison. */ -for (i = 0; i < size; i++) +for (int i = 0; i < size; i++) { int mask; if (mlen == 0) mask = 0; else if (mlen < 32) { - mask = (-1) << (32 - mlen); + mask = (uint)(-1) << (32 - mlen); mlen = 0; } else @@ -1329,9 +1382,9 @@ for (h = host; h != last->next; h = h->next) if (hosts_treat_as_local != NULL) { int rc; - uschar *save = deliver_domain; + const uschar *save = deliver_domain; deliver_domain = h->name; /* set $domain */ - rc = match_isinlist(string_copylc(h->name), &hosts_treat_as_local, 0, + rc = match_isinlist(string_copylc(h->name), CUSS &hosts_treat_as_local, 0, &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL); deliver_domain = save; if (rc == OK) goto FOUND_LOCAL; @@ -1344,9 +1397,8 @@ for (h = host; h != last->next; h = h->next) if (h->address != NULL) { - ip_address_item *ip; if (Ustrcmp(h->address, "0.0.0.0") == 0) goto FOUND_LOCAL; - for (ip = local_interface_data; ip != NULL; ip = ip->next) + for (ip_address_item * ip = local_interface_data; ip; ip = ip->next) if (Ustrcmp(h->address, ip->address) == 0) goto FOUND_LOCAL; yield = HOST_FOUND; /* At least one remote address has been found */ } @@ -1451,10 +1503,11 @@ Returns: OK, DEFER, FAIL static int host_name_lookup_byaddr(void) { -int len; -uschar *s, *t; -struct hostent *hosts; +struct hostent * hosts; struct in_addr addr; +unsigned long time_msec = 0; /* init to quieten dumb static analysis */ + +if (slow_lookup_log) time_msec = get_time_in_ms(); /* Lookup on IPv6 system */ @@ -1490,9 +1543,14 @@ addr.s_addr = (S_ADDR_TYPE)inet_addr(CS sender_host_address); hosts = gethostbyaddr(CS(&addr), sizeof(addr), AF_INET); #endif +if ( slow_lookup_log + && (time_msec = get_time_in_ms() - time_msec) > slow_lookup_log + ) + log_long_lookup(US"gethostbyaddr", sender_host_address, time_msec); + /* Failed to look up the host. */ -if (hosts == NULL) +if (!hosts) { HDEBUG(D_host_lookup) debug_printf("IP address lookup failed: h_errno=%d\n", h_errno); @@ -1503,7 +1561,7 @@ if (hosts == NULL) treat this as non-existent. In some operating systems, this is returned as an empty string; in others as a single dot. */ -if (hosts->h_name == NULL || hosts->h_name[0] == 0 || hosts->h_name[0] == '.') +if (!hosts->h_name || !hosts->h_name[0] || hosts->h_name[0] == '.') { HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an empty name: " "treated as non-existent host name\n"); @@ -1513,29 +1571,29 @@ if (hosts->h_name == NULL || hosts->h_name[0] == 0 || hosts->h_name[0] == '.') /* Copy and lowercase the name, which is in static storage in many systems. Put it in permanent memory. */ -s = (uschar *)hosts->h_name; -len = Ustrlen(s) + 1; -t = sender_host_name = store_get_perm(len); -while (*s != 0) *t++ = tolower(*s++); -*t = 0; + { + int old_pool = store_pool; + store_pool = POOL_TAINT_PERM; /* names are tainted */ -/* If the host has aliases, build a copy of the alias list */ + sender_host_name = string_copylc(US hosts->h_name); -if (hosts->h_aliases != NULL) - { - int count = 1; - uschar **aliases, **ptr; - for (aliases = USS hosts->h_aliases; *aliases != NULL; aliases++) count++; - ptr = sender_host_aliases = store_get_perm(count * sizeof(uschar *)); - for (aliases = USS hosts->h_aliases; *aliases != NULL; aliases++) - { - uschar *s = *aliases; - int len = Ustrlen(s) + 1; - uschar *t = *ptr++ = store_get_perm(len); - while (*s != 0) *t++ = tolower(*s++); - *t = 0; - } - *ptr = NULL; + /* If the host has aliases, build a copy of the alias list */ + + if (hosts->h_aliases) + { + int count = 1; + uschar **ptr; + + for (uschar ** aliases = USS hosts->h_aliases; *aliases; aliases++) count++; + store_pool = POOL_PERM; + ptr = sender_host_aliases = store_get(count * sizeof(uschar *), FALSE); + store_pool = POOL_TAINT_PERM; + + for (uschar ** aliases = USS hosts->h_aliases; *aliases; aliases++) + *ptr++ = string_copylc(*aliases); + *ptr = NULL; + } + store_pool = old_pool; } return OK; @@ -1572,7 +1630,7 @@ Returns: OK on success, the answer being placed in the global variable FAIL if no host name can be found DEFER if a temporary error was encountered -The variable host_lookup_msg is set to an empty string on sucess, or to a +The variable host_lookup_msg is set to an empty string on success, or to a reason for the failure otherwise, in a form suitable for tagging onto an error message, and also host_lookup_failed is set TRUE if the lookup failed. If there was a defer, host_lookup_deferred is set TRUE. @@ -1586,13 +1644,11 @@ host_name_lookup(void) { int old_pool, rc; int sep = 0; -uschar *hname, *save_hostname; +uschar *save_hostname; uschar **aliases; -uschar buffer[256]; uschar *ordername; -uschar *list = host_lookup_order; -dns_record *rr; -dns_answer dnsa; +const uschar *list = host_lookup_order; +dns_answer * dnsa = store_get_dns_answer(); dns_scan dnss; sender_host_dnssec = host_lookup_deferred = host_lookup_failed = FALSE; @@ -1603,7 +1659,7 @@ HDEBUG(D_host_lookup) /* For testing the case when a lookup does not complete, we have a special reserved IP address. */ -if (running_in_test_harness && +if (f.running_in_test_harness && Ustrcmp(sender_host_address, "99.99.99.99") == 0) { HDEBUG(D_host_lookup) @@ -1615,14 +1671,14 @@ if (running_in_test_harness && /* Do lookups directly in the DNS or via gethostbyaddr() (or equivalent), in the order specified by the host_lookup_order option. */ -while ((ordername = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) - != NULL) +while ((ordername = string_nextinlist(&list, &sep, NULL, 0))) { if (strcmpic(ordername, US"bydns") == 0) { + uschar * name = dns_build_reverse(sender_host_address); + dns_init(FALSE, FALSE, FALSE); /* dnssec ctrl by dns_dnssec_ok glbl */ - dns_build_reverse(sender_host_address, buffer); - rc = dns_lookup(&dnsa, buffer, T_PTR, NULL); + rc = dns_lookup_timerwrap(dnsa, name, T_PTR, NULL); /* The first record we come across is used for the name; others are considered to be aliases. We have to scan twice, in order to find out the @@ -1637,66 +1693,60 @@ while ((ordername = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) int count = 0; int old_pool = store_pool; - /* Ideally we'd check DNSSEC both forward and reverse, but we use the - gethost* routines for forward, so can't do that unless/until we rewrite. */ - sender_host_dnssec = dns_is_secure(&dnsa); + sender_host_dnssec = dns_is_secure(dnsa); DEBUG(D_dns) debug_printf("Reverse DNS security status: %s\n", sender_host_dnssec ? "DNSSEC verified (AD)" : "unverified"); store_pool = POOL_PERM; /* Save names in permanent storage */ - for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); - rr != NULL; - rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) - { - if (rr->type == T_PTR) count++; - } + for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); + rr; + rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == T_PTR) + count++; /* Get store for the list of aliases. For compatibility with gethostbyaddr, we make an empty list if there are none. */ - aptr = sender_host_aliases = store_get(count * sizeof(uschar *)); + aptr = sender_host_aliases = store_get(count * sizeof(uschar *), FALSE); /* Re-scan and extract the names */ - for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); - rr != NULL; - rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) + for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); + rr; + rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == T_PTR) { - uschar *s = NULL; - if (rr->type != T_PTR) continue; - s = store_get(ssize); + uschar * s = store_get(ssize, TRUE); /* names are tainted */ /* If an overlong response was received, the data will have been truncated and dn_expand may fail. */ - if (dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, - (uschar *)(rr->data), (DN_EXPAND_ARG4_TYPE)(s), ssize) < 0) + if (dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen, + US (rr->data), (DN_EXPAND_ARG4_TYPE)(s), ssize) < 0) { log_write(0, LOG_MAIN, "host name alias list truncated for %s", sender_host_address); break; } - store_reset(s + Ustrlen(s) + 1); - if (s[0] == 0) + store_release_above(s + Ustrlen(s) + 1); + if (!s[0]) { HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an " "empty name: treated as non-existent host name\n"); continue; } - if (sender_host_name == NULL) sender_host_name = s; - else *aptr++ = s; - while (*s != 0) { *s = tolower(*s); s++; } + if (!sender_host_name) sender_host_name = s; + else *aptr++ = s; + while (*s) { *s = tolower(*s); s++; } } *aptr = NULL; /* End of alias list */ store_pool = old_pool; /* Reset store pool */ - /* If we've found a names, break out of the "order" loop */ + /* If we've found a name, break out of the "order" loop */ - if (sender_host_name != NULL) break; + if (sender_host_name) break; } /* If the DNS lookup deferred, we must also defer. */ @@ -1729,9 +1779,9 @@ while ((ordername = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) /* If we have failed to find a name, return FAIL and log when required. NB host_lookup_msg must be in permanent store. */ -if (sender_host_name == NULL) +if (!sender_host_name) { - if (host_checking || !log_testing_mode) + if (host_checking || !f.log_testing_mode) log_write(L_host_lookup_failed, LOG_MAIN, "no host name found for IP " "address %s", sender_host_address); host_lookup_msg = US" (failed to find host name from IP address)"; @@ -1742,8 +1792,8 @@ if (sender_host_name == NULL) HDEBUG(D_host_lookup) { uschar **aliases = sender_host_aliases; - debug_printf("IP address lookup yielded %s\n", sender_host_name); - while (*aliases != NULL) debug_printf(" alias %s\n", *aliases++); + debug_printf("IP address lookup yielded \"%s\"\n", sender_host_name); + while (*aliases != NULL) debug_printf(" alias \"%s\"\n", *aliases++); } /* We need to verify that a forward lookup on the name we found does indeed @@ -1761,26 +1811,28 @@ the names, and accepts only those that have the correct IP address. */ save_hostname = sender_host_name; /* Save for error messages */ aliases = sender_host_aliases; -for (hname = sender_host_name; hname != NULL; hname = *aliases++) +for (uschar * hname = sender_host_name; hname; hname = *aliases++) { int rc; BOOL ok = FALSE; - host_item h; - h.next = NULL; - h.name = hname; - h.mx = MX_NONE; - h.address = NULL; - - /* When called with the last argument FALSE, host_find_byname() won't return - HOST_FOUND_LOCAL. If the incoming address is an IPv4 address expressed in - IPv6 format, we must compare the IPv4 part to any IPv4 addresses. */ + host_item h = { .next = NULL, .name = hname, .mx = MX_NONE, .address = NULL }; + dnssec_domains d = + { .request = sender_host_dnssec ? US"*" : NULL, .require = NULL }; - if ((rc = host_find_byname(&h, NULL, 0, NULL, FALSE)) == HOST_FOUND) + if ( (rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A | HOST_FIND_BY_AAAA, + NULL, NULL, NULL, &d, NULL, NULL)) == HOST_FOUND + || rc == HOST_FOUND_LOCAL + ) { - host_item *hh; HDEBUG(D_host_lookup) debug_printf("checking addresses for %s\n", hname); - for (hh = &h; hh != NULL; hh = hh->next) - { + + /* If the forward lookup was not secure we cancel the is-secure variable */ + + DEBUG(D_dns) debug_printf("Forward DNS security status: %s\n", + h.dnssec == DS_YES ? "DNSSEC verified (AD)" : "unverified"); + if (h.dnssec != DS_YES) sender_host_dnssec = FALSE; + + for (host_item * hh = &h; hh; hh = hh->next) if (host_is_in_net(hh->address, sender_host_address, 0)) { HDEBUG(D_host_lookup) debug_printf(" %s OK\n", hh->address); @@ -1788,10 +1840,8 @@ for (hname = sender_host_name; hname != NULL; hname = *aliases++) break; } else - { HDEBUG(D_host_lookup) debug_printf(" %s\n", hh->address); - } - } + if (!ok) HDEBUG(D_host_lookup) debug_printf("no IP address for %s matched %s\n", hname, sender_host_address); @@ -1804,9 +1854,7 @@ for (hname = sender_host_name; hname != NULL; hname = *aliases++) return DEFER; } else - { HDEBUG(D_host_lookup) debug_printf("no IP addresses found for %s\n", hname); - } /* If this name is no good, and it's the sender name, set it null pro tem; if it's an alias, just remove it from the list. */ @@ -1892,33 +1940,22 @@ Returns: HOST_FIND_FAILED Failed to find the host or domain */ int -host_find_byname(host_item *host, uschar *ignore_target_hosts, int flags, - uschar **fully_qualified_name, BOOL local_host_check) +host_find_byname(host_item *host, const uschar *ignore_target_hosts, int flags, + const uschar **fully_qualified_name, BOOL local_host_check) { -int i, yield, times; -uschar **addrlist; +int yield, times; host_item *last = NULL; BOOL temp_error = FALSE; #if HAVE_IPV6 int af; #endif -/* If we are in the test harness, a name ending in .test.again.dns always -forces a temporary error response, unless the name is in -dns_again_means_nonexist. */ - -if (running_in_test_harness) - { - uschar *endname = host->name + Ustrlen(host->name); - if (Ustrcmp(endname - 14, "test.again.dns") == 0) goto RETURN_AGAIN; - } - /* Make sure DNS options are set as required. This appears to be necessary in some circumstances when the get..byname() function actually calls the DNS. */ dns_init((flags & HOST_FIND_QUALIFY_SINGLE) != 0, (flags & HOST_FIND_SEARCH_PARENTS) != 0, - FALSE); /*XXX dnssec? */ + FALSE); /* Cannot retrieve dnssec status so do not request */ /* In an IPv6 world, unless IPv6 has been disabled, we need to scan for both kinds of address, so go round the loop twice. Note that we have ensured that @@ -1932,8 +1969,8 @@ lookups here (except when testing standalone). */ #else if (disable_ipv6 || (dns_ipv4_lookup != NULL && - match_isinlist(host->name, &dns_ipv4_lookup, 0, NULL, NULL, MCL_DOMAIN, - TRUE, NULL) == OK)) + match_isinlist(host->name, CUSS &dns_ipv4_lookup, 0, NULL, NULL, + MCL_DOMAIN, TRUE, NULL) == OK)) #endif { af = AF_INET; times = 1; } @@ -1949,11 +1986,11 @@ lookups here (except when testing standalone). */ /* Initialize the flag that gets set for DNS syntax check errors, so that the interface to this function can be similar to host_find_bydns. */ -host_find_failed_syntax = FALSE; +f.host_find_failed_syntax = FALSE; /* Loop to look up both kinds of address in an IPv6 world */ -for (i = 1; i <= times; +for (int i = 1; i <= times; #if HAVE_IPV6 af = AF_INET, /* If 2 passes, IPv4 on the second */ #endif @@ -1962,13 +1999,16 @@ for (i = 1; i <= times; BOOL ipv4_addr; int error_num = 0; struct hostent *hostdata; + unsigned long time_msec = 0; /* compiler quietening */ #ifdef STAND_ALONE printf("Looking up: %s\n", host->name); #endif + if (slow_lookup_log) time_msec = get_time_in_ms(); + #if HAVE_IPV6 - if (running_in_test_harness) + if (f.running_in_test_harness) hostdata = host_fake_gethostbyname(host->name, af, &error_num); else { @@ -1981,7 +2021,7 @@ for (i = 1; i <= times; } #else /* not HAVE_IPV6 */ - if (running_in_test_harness) + if (f.running_in_test_harness) hostdata = host_fake_gethostbyname(host->name, AF_INET, &error_num); else { @@ -1990,27 +2030,32 @@ for (i = 1; i <= times; } #endif /* HAVE_IPV6 */ - if (hostdata == NULL) + if ( slow_lookup_log + && (time_msec = get_time_in_ms() - time_msec) > slow_lookup_log) + log_long_lookup(US"gethostbyname", host->name, time_msec); + + if (!hostdata) { uschar *error; switch (error_num) { case HOST_NOT_FOUND: error = US"HOST_NOT_FOUND"; break; - case TRY_AGAIN: error = US"TRY_AGAIN"; break; - case NO_RECOVERY: error = US"NO_RECOVERY"; break; - case NO_DATA: error = US"NO_DATA"; break; - #if NO_DATA != NO_ADDRESS - case NO_ADDRESS: error = US"NO_ADDRESS"; break; - #endif + case TRY_AGAIN: error = US"TRY_AGAIN"; break; + case NO_RECOVERY: error = US"NO_RECOVERY"; break; + case NO_DATA: error = US"NO_DATA"; break; + #if NO_DATA != NO_ADDRESS + case NO_ADDRESS: error = US"NO_ADDRESS"; break; + #endif default: error = US"?"; break; } DEBUG(D_host_lookup) debug_printf("%s returned %d (%s)\n", + f.running_in_test_harness ? "host_fake_gethostbyname" : #if HAVE_IPV6 #if HAVE_GETIPNODEBYNAME - (af == AF_INET6)? "getipnodebyname(af=inet6)" : "getipnodebyname(af=inet)", + af == AF_INET6 ? "getipnodebyname(af=inet6)" : "getipnodebyname(af=inet)", #else - (af == AF_INET6)? "gethostbyname2(af=inet6)" : "gethostbyname2(af=inet)", + af == AF_INET6 ? "gethostbyname2(af=inet6)" : "gethostbyname2(af=inet)", #endif #else "gethostbyname", @@ -2027,7 +2072,7 @@ for (i = 1; i <= times; if (hostdata->h_name[0] != 0 && Ustrcmp(host->name, hostdata->h_name) != 0) - host->name = string_copy_dnsdomain((uschar *)hostdata->h_name); + host->name = string_copy_dnsdomain(US hostdata->h_name); if (fully_qualified_name != NULL) *fully_qualified_name = host->name; /* Get the list of addresses. IPv4 and IPv6 addresses can be distinguished @@ -2036,7 +2081,7 @@ for (i = 1; i <= times; ipv4_addr = hostdata->h_length == sizeof(struct in_addr); - for (addrlist = USS hostdata->h_addr_list; *addrlist != NULL; addrlist++) + for (uschar ** addrlist = USS hostdata->h_addr_list; *addrlist; addrlist++) { uschar *text_address = host_ntoa(ipv4_addr? AF_INET:AF_INET6, *addrlist, NULL, NULL); @@ -2070,7 +2115,7 @@ for (i = 1; i <= times; else { - host_item *next = store_get(sizeof(host_item)); + host_item *next = store_get(sizeof(host_item), FALSE); next->name = host->name; next->mx = host->mx; next->address = text_address; @@ -2102,7 +2147,7 @@ if (host->address == NULL) HDEBUG(D_host_lookup) debug_printf("%s\n", msg); if (temp_error) goto RETURN_AGAIN; - if (host_checking || !log_testing_mode) + if (host_checking || !f.log_testing_mode) log_write(L_host_lookup_failed, LOG_MAIN, "%s", msg); return HOST_FIND_FAILED; } @@ -2116,8 +2161,7 @@ yield = local_host_check? HDEBUG(D_host_lookup) { - host_item *h; - if (fully_qualified_name != NULL) + if (fully_qualified_name) debug_printf("fully qualified name = %s\n", *fully_qualified_name); debug_printf("%s looked up these IP addresses:\n", #if HAVE_IPV6 @@ -2130,9 +2174,9 @@ HDEBUG(D_host_lookup) "gethostbyname" #endif ); - for (h = host; h != last->next; h = h->next) + for (const host_item * h = host; h != last->next; h = h->next) debug_printf(" name=%s address=%s\n", h->name, - (h->address == NULL)? US"" : h->address); + h->address ? h->address : US""); } /* Return the found status. */ @@ -2146,9 +2190,9 @@ RETURN_AGAIN: { #ifndef STAND_ALONE int rc; - uschar *save = deliver_domain; + const uschar *save = deliver_domain; deliver_domain = host->name; /* set $domain */ - rc = match_isinlist(host->name, &dns_again_means_nonexist, 0, NULL, NULL, + rc = match_isinlist(host->name, CUSS &dns_again_means_nonexist, 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL); deliver_domain = save; if (rc == OK) @@ -2173,9 +2217,7 @@ field set to NULL, fill in its IP address from the DNS. If it is multi-homed, create additional host items for the additional addresses, copying all the other fields, and randomizing the order. -On IPv6 systems, A6 records are sought first (but only if support for A6 is -configured - they may never become mainstream), then AAAA records are sought, -and finally A records are sought as well. +On IPv6 systems, AAAA records are sought first, then A records. The host name may be changed if the DNS returns a different name - e.g. fully qualified or changed via CNAME. If fully_qualified_name is not NULL, dns_lookup @@ -2196,22 +2238,26 @@ Arguments: fully_qualified_name if not NULL, return fully qualified name here if the contents are different (i.e. it must be preset to something) - dnnssec_require if TRUE check the DNS result AD bit + dnssec_request if TRUE request the AD bit + dnssec_require if TRUE require the AD bit + whichrrs select ipv4, ipv6 results Returns: HOST_FIND_FAILED couldn't find A record HOST_FIND_AGAIN try again later + HOST_FIND_SECURITY dnssec required but not acheived HOST_FOUND found AAAA and/or A record(s) HOST_IGNORED found, but all IPs ignored */ static int set_address_from_dns(host_item *host, host_item **lastptr, - uschar *ignore_target_hosts, BOOL allow_ip, uschar **fully_qualified_name, - BOOL dnssec_request, BOOL dnssec_require) + const uschar *ignore_target_hosts, BOOL allow_ip, + const uschar **fully_qualified_name, + BOOL dnssec_request, BOOL dnssec_require, int whichrrs) { -dns_record *rr; host_item *thishostlast = NULL; /* Indicates not yet filled in anything */ BOOL v6_find_again = FALSE; +BOOL dnssec_fail = FALSE; int i; /* If allow_ip is set, a name which is an IP address returns that value @@ -2221,8 +2267,8 @@ those sites that feel they have to flaunt the RFC rules. */ if (allow_ip && string_is_ip_address(host->name, NULL) != 0) { #ifndef STAND_ALONE - if (ignore_target_hosts != NULL && - verify_check_this_host(&ignore_target_hosts, NULL, host->name, + if ( ignore_target_hosts + && verify_check_this_host(&ignore_target_hosts, NULL, host->name, host->name, NULL) == OK) return HOST_IGNORED; #endif @@ -2231,27 +2277,24 @@ if (allow_ip && string_is_ip_address(host->name, NULL) != 0) return HOST_FOUND; } -/* On an IPv6 system, unless IPv6 is disabled, go round the loop up to three -times, looking for A6 and AAAA records the first two times. However, unless -doing standalone testing, we force an IPv4 lookup if the domain matches -dns_ipv4_lookup is set. Since A6 records look like being abandoned, support -them only if explicitly configured to do so. On an IPv4 system, go round the -loop once only, looking only for A records. */ +/* On an IPv6 system, unless IPv6 is disabled, go round the loop up to twice, +looking for AAAA records the first time. However, unless doing standalone +testing, we force an IPv4 lookup if the domain matches dns_ipv4_lookup global. +On an IPv4 system, go round the loop once only, looking only for A records. */ #if HAVE_IPV6 #ifndef STAND_ALONE - if (disable_ipv6 || (dns_ipv4_lookup != NULL && - match_isinlist(host->name, &dns_ipv4_lookup, 0, NULL, NULL, MCL_DOMAIN, - TRUE, NULL) == OK)) + if ( disable_ipv6 + || !(whichrrs & HOST_FIND_BY_AAAA) + || (dns_ipv4_lookup + && match_isinlist(host->name, CUSS &dns_ipv4_lookup, 0, NULL, NULL, + MCL_DOMAIN, TRUE, NULL) == OK) + ) i = 0; /* look up A records only */ else #endif /* STAND_ALONE */ - #ifdef SUPPORT_A6 - i = 2; /* look up A6 and AAAA and A records */ - #else i = 1; /* look up AAAA and A records */ - #endif /* SUPPORT_A6 */ /* The IPv4 world */ @@ -2261,17 +2304,25 @@ loop once only, looking only for A records. */ for (; i >= 0; i--) { - static int types[] = { T_A, T_AAAA, T_A6 }; + static int types[] = { T_A, T_AAAA }; int type = types[i]; - int randoffset = (i == 0)? 500 : 0; /* Ensures v6 sorts before v4 */ - dns_answer dnsa; + int randoffset = i == (whichrrs & HOST_FIND_IPV4_FIRST ? 1 : 0) + ? 500 : 0; /* Ensures v6/4 sort order */ + dns_answer * dnsa = store_get_dns_answer(); dns_scan dnss; - int rc = dns_lookup(&dnsa, host->name, type, fully_qualified_name); + int rc = dns_lookup_timerwrap(dnsa, host->name, type, fully_qualified_name); lookup_dnssec_authenticated = !dnssec_request ? NULL - : dns_is_secure(&dnsa) ? US"yes" : US"no"; + : dns_is_secure(dnsa) ? US"yes" : US"no"; + + DEBUG(D_dns) + if ( (dnssec_request || dnssec_require) + && !dns_is_secure(dnsa) + && dns_is_aa(dnsa) + ) + debug_printf("DNS lookup of %.256s (A/AAAA) requested AD, but got AA\n", host->name); - /* We want to return HOST_FIND_AGAIN if one of the A, A6, or AAAA lookups + /* We want to return HOST_FIND_AGAIN if one of the A or AAAA lookups fails or times out, but not if another one succeeds. (In the early IPv6 days there are name servers that always fail on AAAA, but are happy to give out an A record. We want to proceed with that A record.) */ @@ -2280,13 +2331,13 @@ for (; i >= 0; i--) { if (i == 0) /* Just tried for an A record, i.e. end of loop */ { - if (host->address != NULL) return HOST_FOUND; /* A6 or AAAA was found */ + if (host->address != NULL) return HOST_FOUND; /* AAAA was found */ if (rc == DNS_AGAIN || rc == DNS_FAIL || v6_find_again) return HOST_FIND_AGAIN; return HOST_FIND_FAILED; /* DNS_NOMATCH or DNS_NODATA */ } - /* Tried for an A6 or AAAA record: remember if this was a temporary + /* Tried for an AAAA record: remember if this was a temporary error, and look for the next record type. */ if (rc != DNS_NOMATCH && rc != DNS_NODATA) v6_find_again = TRUE; @@ -2295,7 +2346,7 @@ for (; i >= 0; i--) if (dnssec_request) { - if (dns_is_secure(&dnsa)) + if (dns_is_secure(dnsa)) { DEBUG(D_host_lookup) debug_printf("%s A DNSSEC\n", host->name); if (host->dnssec == DS_UNK) /* set in host_find_bydns() */ @@ -2305,9 +2356,9 @@ for (; i >= 0; i--) { if (dnssec_require) { - log_write(L_host_lookup_failed, LOG_MAIN, - "dnssec fail on %s for %.256s", - i>1 ? "A6" : i>0 ? "AAAA" : "A", host->name); + dnssec_fail = TRUE; + DEBUG(D_host_lookup) debug_printf("dnssec fail on %s for %.256s", + i>0 ? "AAAA" : "A", host->name); continue; } if (host->dnssec == DS_YES) /* set in host_find_bydns() */ @@ -2321,120 +2372,118 @@ for (; i >= 0; i--) /* Lookup succeeded: fill in the given host item with the first non-ignored address found; create additional items for any others. A single A6 record - may generate more than one address. */ + may generate more than one address. The lookup had a chance to update the + fqdn; we do not want any later times round the loop to do so. */ - for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); - rr != NULL; - rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) - { - if (rr->type == type) - { - /* dns_address *da = dns_address_from_rr(&dnsa, rr); */ + fully_qualified_name = NULL; - dns_address *da; - da = dns_address_from_rr(&dnsa, rr); + for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); + rr; + rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == type) + { + dns_address * da = dns_address_from_rr(dnsa, rr); - DEBUG(D_host_lookup) - { - if (da == NULL) - debug_printf("no addresses extracted from A6 RR for %s\n", - host->name); - } + DEBUG(D_host_lookup) + if (!da) debug_printf("no addresses extracted from A6 RR for %s\n", + host->name); - /* This loop runs only once for A and AAAA records, but may run - several times for an A6 record that generated multiple addresses. */ + /* This loop runs only once for A and AAAA records, but may run + several times for an A6 record that generated multiple addresses. */ - for (; da != NULL; da = da->next) - { - #ifndef STAND_ALONE - if (ignore_target_hosts != NULL && - verify_check_this_host(&ignore_target_hosts, NULL, - host->name, da->address, NULL) == OK) - { - DEBUG(D_host_lookup) - debug_printf("ignored host %s [%s]\n", host->name, da->address); - continue; - } - #endif + for (; da; da = da->next) + { + #ifndef STAND_ALONE + if (ignore_target_hosts != NULL && + verify_check_this_host(&ignore_target_hosts, NULL, + host->name, da->address, NULL) == OK) + { + DEBUG(D_host_lookup) + debug_printf("ignored host %s [%s]\n", host->name, da->address); + continue; + } + #endif - /* If this is the first address, stick it in the given host block, - and change the name if the returned RR has a different name. */ + /* If this is the first address, stick it in the given host block, + and change the name if the returned RR has a different name. */ - if (thishostlast == NULL) - { - if (strcmpic(host->name, rr->name) != 0) - host->name = string_copy_dnsdomain(rr->name); - host->address = da->address; - host->sort_key = host->mx * 1000 + random_number(500) + randoffset; - host->status = hstatus_unknown; - host->why = hwhy_unknown; - thishostlast = host; - } + if (thishostlast == NULL) + { + if (strcmpic(host->name, rr->name) != 0) + host->name = string_copy_dnsdomain(rr->name); + host->address = da->address; + host->sort_key = host->mx * 1000 + random_number(500) + randoffset; + host->status = hstatus_unknown; + host->why = hwhy_unknown; + thishostlast = host; + } - /* Not the first address. Check for, and ignore, duplicates. Then - insert in the chain at a random point. */ + /* Not the first address. Check for, and ignore, duplicates. Then + insert in the chain at a random point. */ - else - { - int new_sort_key; - host_item *next; - - /* End of our local chain is specified by "thishostlast". */ - - for (next = host;; next = next->next) - { - if (Ustrcmp(CS da->address, next->address) == 0) break; - if (next == thishostlast) { next = NULL; break; } - } - if (next != NULL) continue; /* With loop for next address */ - - /* Not a duplicate */ - - new_sort_key = host->mx * 1000 + random_number(500) + randoffset; - next = store_get(sizeof(host_item)); - - /* New address goes first: insert the new block after the first one - (so as not to disturb the original pointer) but put the new address - in the original block. */ - - if (new_sort_key < host->sort_key) - { - *next = *host; /* Copies port */ - host->next = next; - host->address = da->address; - host->sort_key = new_sort_key; - if (thishostlast == host) thishostlast = next; /* Local last */ - if (*lastptr == host) *lastptr = next; /* Global last */ - } - - /* Otherwise scan down the addresses for this host to find the - one to insert after. */ - - else - { - host_item *h = host; - while (h != thishostlast) - { - if (new_sort_key < h->next->sort_key) break; - h = h->next; - } - *next = *h; /* Copies port */ - h->next = next; - next->address = da->address; - next->sort_key = new_sort_key; - if (h == thishostlast) thishostlast = next; /* Local last */ - if (h == *lastptr) *lastptr = next; /* Global last */ - } - } - } + else + { + int new_sort_key; + host_item *next; + + /* End of our local chain is specified by "thishostlast". */ + + for (next = host;; next = next->next) + { + if (Ustrcmp(CS da->address, next->address) == 0) break; + if (next == thishostlast) { next = NULL; break; } + } + if (next != NULL) continue; /* With loop for next address */ + + /* Not a duplicate */ + + new_sort_key = host->mx * 1000 + random_number(500) + randoffset; + next = store_get(sizeof(host_item), FALSE); + + /* New address goes first: insert the new block after the first one + (so as not to disturb the original pointer) but put the new address + in the original block. */ + + if (new_sort_key < host->sort_key) + { + *next = *host; /* Copies port */ + host->next = next; + host->address = da->address; + host->sort_key = new_sort_key; + if (thishostlast == host) thishostlast = next; /* Local last */ + if (*lastptr == host) *lastptr = next; /* Global last */ + } + + /* Otherwise scan down the addresses for this host to find the + one to insert after. */ + + else + { + host_item *h = host; + while (h != thishostlast) + { + if (new_sort_key < h->next->sort_key) break; + h = h->next; + } + *next = *h; /* Copies port */ + h->next = next; + next->address = da->address; + next->sort_key = new_sort_key; + if (h == thishostlast) thishostlast = next; /* Local last */ + if (h == *lastptr) *lastptr = next; /* Global last */ + } + } } } } -/* Control gets here only if the third lookup (the A record) succeeded. +/* Control gets here only if the second lookup (the A record) succeeded. However, the address may not be filled in if it was ignored. */ -return (host->address == NULL)? HOST_IGNORED : HOST_FOUND; +return host->address + ? HOST_FOUND + : dnssec_fail + ? HOST_FIND_SECURITY + : HOST_IGNORED; } @@ -2457,15 +2506,18 @@ Arguments: whichrrs flags indicating which RRs to look for: HOST_FIND_BY_SRV => look for SRV HOST_FIND_BY_MX => look for MX - HOST_FIND_BY_A => look for A or AAAA + HOST_FIND_BY_A => look for A + HOST_FIND_BY_AAAA => look for AAAA also flags indicating how the lookup is done HOST_FIND_QUALIFY_SINGLE ) passed to the HOST_FIND_SEARCH_PARENTS ) resolver + HOST_FIND_IPV4_FIRST => reverse usual result ordering + HOST_FIND_IPV4_ONLY => MX results elide ipv6 srv_service when SRV used, the service name srv_fail_domains DNS errors for these domains => assume nonexist mx_fail_domains DNS errors for these domains => assume nonexist - dnssec_request_domains => make dnssec request - dnssec_require_domains => ditto and nonexist failures + dnssec_d.request => make dnssec request: domainlist + dnssec_d.require => ditto and nonexist failures fully_qualified_name if not NULL, return fully-qualified name removed set TRUE if local host was removed from the list @@ -2473,6 +2525,7 @@ Returns: HOST_FIND_FAILED Failed to find the host or domain; if there was a syntax error, host_find_failed_syntax is set. HOST_FIND_AGAIN Could not resolve at this time + HOST_FIND_SECURITY dnsssec required but not acheived HOST_FOUND Host found HOST_FOUND_LOCAL The lowest MX record points to this machine, if MX records were found, or @@ -2481,23 +2534,24 @@ Returns: HOST_FIND_FAILED Failed to find the host or domain; */ int -host_find_bydns(host_item *host, uschar *ignore_target_hosts, int whichrrs, +host_find_bydns(host_item *host, const uschar *ignore_target_hosts, int whichrrs, uschar *srv_service, uschar *srv_fail_domains, uschar *mx_fail_domains, - uschar *dnssec_request_domains, uschar *dnssec_require_domains, - uschar **fully_qualified_name, BOOL *removed) + const dnssec_domains *dnssec_d, + const uschar **fully_qualified_name, BOOL *removed) { host_item *h, *last; -dns_record *rr; int rc = DNS_FAIL; int ind_type = 0; int yield; -dns_answer dnsa; +dns_answer * dnsa = store_get_dns_answer(); dns_scan dnss; -BOOL dnssec_require = match_isinlist(host->name, &dnssec_require_domains, +BOOL dnssec_require = dnssec_d + && match_isinlist(host->name, CUSS &dnssec_d->require, 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL) == OK; BOOL dnssec_request = dnssec_require - || match_isinlist(host->name, &dnssec_request_domains, - 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL) == OK; + || ( dnssec_d + && match_isinlist(host->name, CUSS &dnssec_d->request, + 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL) == OK); dnssec_status_t dnssec; /* Set the default fully qualified name to the incoming name, initialize the @@ -2507,22 +2561,22 @@ that gets set for DNS syntax check errors. */ if (fully_qualified_name != NULL) *fully_qualified_name = host->name; dns_init((whichrrs & HOST_FIND_QUALIFY_SINGLE) != 0, (whichrrs & HOST_FIND_SEARCH_PARENTS) != 0, - dnssec_request - ); -host_find_failed_syntax = FALSE; + dnssec_request); +f.host_find_failed_syntax = FALSE; /* First, if requested, look for SRV records. The service name is given; we -assume TCP progocol. DNS domain names are constrained to a maximum of 256 +assume TCP protocol. DNS domain names are constrained to a maximum of 256 characters, so the code below should be safe. */ -if ((whichrrs & HOST_FIND_BY_SRV) != 0) +if (whichrrs & HOST_FIND_BY_SRV) { - uschar buffer[300]; - uschar *temp_fully_qualified_name = buffer; + gstring * g; + uschar * temp_fully_qualified_name; int prefix_length; - (void)sprintf(CS buffer, "_%s._tcp.%n%.256s", srv_service, &prefix_length, - host->name); + g = string_fmt_append(NULL, "_%s._tcp.%n%.256s", + srv_service, &prefix_length, host->name); + temp_fully_qualified_name = string_from_gstring(g); ind_type = T_SRV; /* Search for SRV records. If the fully qualified name is different to @@ -2531,23 +2585,30 @@ if ((whichrrs & HOST_FIND_BY_SRV) != 0) dnssec = DS_UNK; lookup_dnssec_authenticated = NULL; - rc = dns_lookup(&dnsa, buffer, ind_type, &temp_fully_qualified_name); + rc = dns_lookup_timerwrap(dnsa, temp_fully_qualified_name, ind_type, + CUSS &temp_fully_qualified_name); + + DEBUG(D_dns) + if ((dnssec_request || dnssec_require) + && !dns_is_secure(dnsa) + && dns_is_aa(dnsa)) + debug_printf("DNS lookup of %.256s (SRV) requested AD, but got AA\n", host->name); if (dnssec_request) { - if (dns_is_secure(&dnsa)) + if (dns_is_secure(dnsa)) { dnssec = DS_YES; lookup_dnssec_authenticated = US"yes"; } else { dnssec = DS_NO; lookup_dnssec_authenticated = US"no"; } } - if (temp_fully_qualified_name != buffer && fully_qualified_name != NULL) + if (temp_fully_qualified_name != g->s && fully_qualified_name != NULL) *fully_qualified_name = temp_fully_qualified_name + prefix_length; /* On DNS failures, we give the "try again" error unless the domain is listed as one for which we continue. */ - if (rc == DNS_SUCCEED && dnssec_require && !dns_is_secure(&dnsa)) + if (rc == DNS_SUCCEED && dnssec_require && !dns_is_secure(dnsa)) { log_write(L_host_lookup_failed, LOG_MAIN, "dnssec fail on SRV for %.256s", host->name); @@ -2556,8 +2617,8 @@ if ((whichrrs & HOST_FIND_BY_SRV) != 0) if (rc == DNS_FAIL || rc == DNS_AGAIN) { #ifndef STAND_ALONE - if (match_isinlist(host->name, &srv_fail_domains, 0, NULL, NULL, MCL_DOMAIN, - TRUE, NULL) != OK) + if (match_isinlist(host->name, CUSS &srv_fail_domains, 0, NULL, NULL, + MCL_DOMAIN, TRUE, NULL) != OK) #endif { yield = HOST_FIND_AGAIN; goto out; } DEBUG(D_host_lookup) debug_printf("DNS_%s treated as DNS_NODATA " @@ -2572,25 +2633,29 @@ same domain. The result will be DNS_NODATA if the domain exists but has no MX records. On DNS failures, we give the "try again" error unless the domain is listed as one for which we continue. */ -if (rc != DNS_SUCCEED && (whichrrs & HOST_FIND_BY_MX) != 0) +if (rc != DNS_SUCCEED && whichrrs & HOST_FIND_BY_MX) { ind_type = T_MX; dnssec = DS_UNK; lookup_dnssec_authenticated = NULL; - rc = dns_lookup(&dnsa, host->name, ind_type, fully_qualified_name); + rc = dns_lookup_timerwrap(dnsa, host->name, ind_type, fully_qualified_name); + + DEBUG(D_dns) + if ( (dnssec_request || dnssec_require) + && !dns_is_secure(dnsa) + && dns_is_aa(dnsa)) + debug_printf("DNS lookup of %.256s (MX) requested AD, but got AA\n", host->name); if (dnssec_request) - { - if (dns_is_secure(&dnsa)) - { - DEBUG(D_host_lookup) debug_printf("%s MX DNSSEC\n", host->name); + if (dns_is_secure(dnsa)) + { + DEBUG(D_host_lookup) debug_printf("%s (MX resp) DNSSEC\n", host->name); dnssec = DS_YES; lookup_dnssec_authenticated = US"yes"; } else { dnssec = DS_NO; lookup_dnssec_authenticated = US"no"; } - } switch (rc) { @@ -2598,19 +2663,24 @@ if (rc != DNS_SUCCEED && (whichrrs & HOST_FIND_BY_MX) != 0) yield = HOST_FIND_FAILED; goto out; case DNS_SUCCEED: - if (!dnssec_require || dns_is_secure(&dnsa)) + if (!dnssec_require || dns_is_secure(dnsa)) break; - log_write(L_host_lookup_failed, LOG_MAIN, - "dnssec fail on MX for %.256s", host->name); + DEBUG(D_host_lookup) + debug_printf("dnssec fail on MX for %.256s", host->name); +#ifndef STAND_ALONE + if (match_isinlist(host->name, CUSS &mx_fail_domains, 0, NULL, NULL, + MCL_DOMAIN, TRUE, NULL) != OK) + { yield = HOST_FIND_SECURITY; goto out; } +#endif rc = DNS_FAIL; /*FALLTHROUGH*/ case DNS_FAIL: case DNS_AGAIN: - #ifndef STAND_ALONE - if (match_isinlist(host->name, &mx_fail_domains, 0, NULL, NULL, MCL_DOMAIN, - TRUE, NULL) != OK) - #endif +#ifndef STAND_ALONE + if (match_isinlist(host->name, CUSS &mx_fail_domains, 0, NULL, NULL, + MCL_DOMAIN, TRUE, NULL) != OK) +#endif { yield = HOST_FIND_AGAIN; goto out; } DEBUG(D_host_lookup) debug_printf("DNS_%s treated as DNS_NODATA " "(domain in mx_fail_domains)\n", (rc == DNS_FAIL)? "FAIL":"AGAIN"); @@ -2624,7 +2694,7 @@ host. */ if (rc != DNS_SUCCEED) { - if ((whichrrs & HOST_FIND_BY_A) == 0) + if (!(whichrrs & (HOST_FIND_BY_A | HOST_FIND_BY_AAAA))) { DEBUG(D_host_lookup) debug_printf("Address records are not being sought\n"); yield = HOST_FIND_FAILED; @@ -2637,7 +2707,7 @@ if (rc != DNS_SUCCEED) host->dnssec = DS_UNK; lookup_dnssec_authenticated = NULL; rc = set_address_from_dns(host, &last, ignore_target_hosts, FALSE, - fully_qualified_name, dnssec_request, dnssec_require); + fully_qualified_name, dnssec_request, dnssec_require, whichrrs); /* If one or more address records have been found, check that none of them are local. Since we know the host items all have their IP addresses @@ -2651,18 +2721,15 @@ if (rc != DNS_SUCCEED) if (rc == HOST_IGNORED) rc = HOST_FIND_FAILED; /* No special action */ DEBUG(D_host_lookup) - { - host_item *h; - if (host->address != NULL) + if (host->address) { - if (fully_qualified_name != NULL) + if (fully_qualified_name) debug_printf("fully qualified name = %s\n", *fully_qualified_name); - for (h = host; h != last->next; h = h->next) + for (host_item * h = host; h != last->next; h = h->next) debug_printf("%s %s mx=%d sort=%d %s\n", h->name, - (h->address == NULL)? US"" : h->address, h->mx, h->sort_key, - (h->status >= hstatus_unusable)? US"*" : US""); + h->address ? h->address : US"", h->mx, h->sort_key, + h->status >= hstatus_unusable ? US"*" : US""); } - } yield = rc; goto out; @@ -2690,18 +2757,15 @@ host which is not the primary hostname. */ last = NULL; /* Indicates that not even the first item is filled yet */ -for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); - rr != NULL; - rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) +for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); + rr; + rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == ind_type) { - int precedence; - int weight = 0; /* For SRV records */ + int precedence, weight; int port = PORT_NONE; - uschar *s; /* MUST be unsigned for GETSHORT */ + const uschar * s = rr->data; /* MUST be unsigned for GETSHORT */ uschar data[256]; - if (rr->type != ind_type) continue; - s = rr->data; GETSHORT(precedence, s); /* Pointer s is advanced */ /* For MX records, we use a random "weight" which causes multiple records of @@ -2709,20 +2773,18 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); if (ind_type == T_MX) weight = random_number(500); - - /* SRV records are specified with a port and a weight. The weight is used - in a special algorithm. However, to start with, we just use it to order the - records of equal priority (precedence). */ - else { + /* SRV records are specified with a port and a weight. The weight is used + in a special algorithm. However, to start with, we just use it to order the + records of equal priority (precedence). */ GETSHORT(weight, s); GETSHORT(port, s); } /* Get the name of the host pointed to. */ - (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, s, + (void)dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen, s, (DN_EXPAND_ARG4_TYPE)data, sizeof(data)); /* Check that we haven't already got this host on the chain; if we have, @@ -2730,17 +2792,16 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); never know what junk might get into the DNS (and this case has been seen on more than one occasion). */ - if (last != NULL) /* This is not the first record */ + if (last) /* This is not the first record */ { host_item *prev = NULL; for (h = host; h != last->next; prev = h, h = h->next) - { if (strcmpic(h->name, data) == 0) { DEBUG(D_host_lookup) debug_printf("discarded duplicate host %s (MX=%d)\n", data, - (precedence > h->mx)? precedence : h->mx); + precedence > h->mx ? precedence : h->mx); if (precedence >= h->mx) goto NEXT_MX_RR; /* Skip greater precedence */ if (h == host) /* Override first item */ { @@ -2756,14 +2817,13 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); if (h == last) last = prev; break; } - } } /* If this is the first MX or SRV record, put the data into the existing host block. Otherwise, add a new block in the correct place; if it has to be before the first block, copy the first block's data to a new second block. */ - if (last == NULL) + if (!last) { host->name = string_copy_dnsdomain(data); host->address = NULL; @@ -2775,13 +2835,12 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); host->dnssec = dnssec; last = host; } + else /* Make a new host item and seek the correct insertion place */ - - else { int sort_key = precedence * 1000 + weight; - host_item *next = store_get(sizeof(host_item)); + host_item *next = store_get(sizeof(host_item), FALSE); next->name = string_copy_dnsdomain(data); next->address = NULL; next->port = port; @@ -2803,21 +2862,18 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); host->next = next; if (last == host) last = next; } + else /* Else scan down the items we have inserted as part of this exercise; don't go further. */ - - else { for (h = host; h != last; h = h->next) - { if (sort_key < h->next->sort_key) { next->next = h->next; h->next = next; break; } - } /* Join on after the last host item that's part of this processing if we haven't stopped sooner. */ @@ -2834,6 +2890,12 @@ for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); NEXT_MX_RR: continue; } +if (!last) /* No rr of correct type; give up */ + { + yield = HOST_FIND_FAILED; + goto out; + } + /* If the list of hosts was obtained from SRV records, there are two things to do. First, if there is only one host, and it's name is ".", it means there is no SMTP service at this domain. Otherwise, we have to sort the hosts of equal @@ -2844,7 +2906,7 @@ remaining in the same priority group. */ if (ind_type == T_SRV) { - host_item **pptr; + host_item ** pptr; if (host == last && host->name[0] == 0) { @@ -2860,7 +2922,7 @@ if (ind_type == T_SRV) debug_printf(" %s P=%d W=%d\n", h->name, h->mx, h->sort_key % 1000); } - for (pptr = &host, h = host; h != last; pptr = &(h->next), h = h->next) + for (pptr = &host, h = host; h != last; pptr = &h->next, h = h->next) { int sum = 0; host_item *hh; @@ -2888,10 +2950,9 @@ if (ind_type == T_SRV) for (ppptr = pptr, hhh = h; hhh != hh; - ppptr = &(hhh->next), hhh = hhh->next) - { - if (hhh->sort_key >= randomizer) break; - } + ppptr = &hhh->next, hhh = hhh->next) + if (hhh->sort_key >= randomizer) + break; /* hhh now points to the host that should go first; ppptr points to the place that points to it. Unfortunately, if the start of the minilist is @@ -2916,7 +2977,6 @@ if (ind_type == T_SRV) hhh->next = temp.next; h->next = hhh; } - else { hhh->next = h; /* The rest of the chain follows it */ @@ -2965,19 +3025,22 @@ dns_init(FALSE, FALSE, /* Disable qualify_single and search_parents */ for (h = host; h != last->next; h = h->next) { - if (h->address != NULL) continue; /* Inserted by a multihomed host */ + if (h->address) continue; /* Inserted by a multihomed host */ + rc = set_address_from_dns(h, &last, ignore_target_hosts, allow_mx_to_ip, - NULL, dnssec_request, dnssec_require); + NULL, dnssec_request, dnssec_require, + whichrrs & HOST_FIND_IPV4_ONLY + ? HOST_FIND_BY_A : HOST_FIND_BY_A | HOST_FIND_BY_AAAA); if (rc != HOST_FOUND) { h->status = hstatus_unusable; - if (rc == HOST_FIND_AGAIN) + switch (rc) { - yield = rc; - h->why = hwhy_deferred; + case HOST_FIND_AGAIN: yield = rc; h->why = hwhy_deferred; break; + case HOST_FIND_SECURITY: yield = rc; h->why = hwhy_insecure; break; + case HOST_IGNORED: h->why = hwhy_ignored; break; + default: h->why = hwhy_failed; break; } - else - h->why = (rc == HOST_IGNORED)? hwhy_ignored : hwhy_failed; } } @@ -2986,7 +3049,7 @@ been explicitly ignored, and remove them from the list, as if they did not exist. If we end up with just a single, ignored host, flatten its fields as if nothing was found. */ -if (ignore_target_hosts != NULL) +if (ignore_target_hosts) { host_item *prev = NULL; for (h = host; h != last->next; h = h->next) @@ -3022,24 +3085,32 @@ single MX preference value, IPv6 addresses come first. This can separate the addresses of a multihomed host, but that should not matter. */ #if HAVE_IPV6 -if (h != last && !disable_ipv6) +if (h != last && !disable_ipv6) for (h = host; h != last; h = h->next) { - for (h = host; h != last; h = h->next) - { - host_item temp; - host_item *next = h->next; - if (h->mx != next->mx || /* If next is different MX */ - h->address == NULL || /* OR this one is unset */ - Ustrchr(h->address, ':') != NULL || /* OR this one is IPv6 */ - (next->address != NULL && - Ustrchr(next->address, ':') == NULL)) /* OR next is IPv4 */ - continue; /* move on to next */ - temp = *h; /* otherwise, swap */ - temp.next = next->next; - *h = *next; - h->next = next; - *next = temp; - } + host_item temp; + host_item *next = h->next; + + if ( h->mx != next->mx /* If next is different MX */ + || !h->address /* OR this one is unset */ + ) + continue; /* move on to next */ + + if ( whichrrs & HOST_FIND_IPV4_FIRST + ? !Ustrchr(h->address, ':') /* OR this one is IPv4 */ + || next->address + && Ustrchr(next->address, ':') /* OR next is IPv6 */ + + : Ustrchr(h->address, ':') /* OR this one is IPv6 */ + || next->address + && !Ustrchr(next->address, ':') /* OR next is IPv4 */ + ) + continue; /* move on to next */ + + temp = *h; /* otherwise, swap */ + temp.next = next->next; + *h = *next; + h->next = next; + *next = temp; } #endif @@ -3058,18 +3129,20 @@ if (rc != HOST_FIND_FAILED) yield = rc; DEBUG(D_host_lookup) { - if (fully_qualified_name != NULL) + if (fully_qualified_name) debug_printf("fully qualified name = %s\n", *fully_qualified_name); debug_printf("host_find_bydns yield = %s (%d); returned hosts:\n", - (yield == HOST_FOUND)? "HOST_FOUND" : - (yield == HOST_FOUND_LOCAL)? "HOST_FOUND_LOCAL" : - (yield == HOST_FIND_AGAIN)? "HOST_FIND_AGAIN" : - (yield == HOST_FIND_FAILED)? "HOST_FIND_FAILED" : "?", + yield == HOST_FOUND ? "HOST_FOUND" : + yield == HOST_FOUND_LOCAL ? "HOST_FOUND_LOCAL" : + yield == HOST_FIND_SECURITY ? "HOST_FIND_SECURITY" : + yield == HOST_FIND_AGAIN ? "HOST_FIND_AGAIN" : + yield == HOST_FIND_FAILED ? "HOST_FIND_FAILED" : "?", yield); for (h = host; h != last->next; h = h->next) { - debug_printf(" %s %s MX=%d ", h->name, - (h->address == NULL)? US"" : h->address, h->mx); + debug_printf(" %s %s MX=%d %s", h->name, + !h->address ? US"" : h->address, h->mx, + h->dnssec == DS_YES ? US"DNSSEC " : US""); if (h->port != PORT_NONE) debug_printf("port=%d ", h->port); if (h->status >= hstatus_unusable) debug_printf("*"); debug_printf("\n"); @@ -3085,6 +3158,76 @@ return yield; +#ifdef SUPPORT_DANE +/* Lookup TLSA record for host/port. +Return: OK success with dnssec; DANE mode + DEFER Do not use this host now, may retry later + FAIL_FORCED No TLSA record; DANE not usable + FAIL Do not use this connection +*/ + +int +tlsa_lookup(const host_item * host, dns_answer * dnsa, BOOL dane_required) +{ +uschar buffer[300]; +const uschar * fullname = buffer; +int rc; +BOOL sec; + +/* TLSA lookup string */ +(void)sprintf(CS buffer, "_%d._tcp.%.256s", host->port, host->name); + +rc = dns_lookup_timerwrap(dnsa, buffer, T_TLSA, &fullname); +sec = dns_is_secure(dnsa); +DEBUG(D_transport) + debug_printf("TLSA lookup ret %d %sDNSSEC\n", rc, sec ? "" : "not "); + +switch (rc) + { + case DNS_AGAIN: + return DEFER; /* just defer this TLS'd conn */ + + case DNS_SUCCEED: + if (sec) + { + DEBUG(D_transport) + { + dns_scan dnss; + for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr; + rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) + if (rr->type == T_TLSA && rr->size > 3) + { + uint16_t payload_length = rr->size - 3; + uschar s[MAX_TLSA_EXPANDED_SIZE], * sp = s, * p = US rr->data; + + sp += sprintf(CS sp, "%d ", *p++); /* usage */ + sp += sprintf(CS sp, "%d ", *p++); /* selector */ + sp += sprintf(CS sp, "%d ", *p++); /* matchtype */ + while (payload_length-- > 0 && sp-s < (MAX_TLSA_EXPANDED_SIZE - 4)) + sp += sprintf(CS sp, "%02x", *p++); + + debug_printf(" %s\n", s); + } + } + return OK; + } + log_write(0, LOG_MAIN, + "DANE error: TLSA lookup for %s not DNSSEC", host->name); + /*FALLTRHOUGH*/ + + case DNS_NODATA: /* no TLSA RR for this lookup */ + case DNS_NOMATCH: /* no records at all for this lookup */ + return dane_required ? FAIL : FAIL_FORCED; + + default: + case DNS_FAIL: + return dane_required ? FAIL : DEFER; + } +} +#endif /*SUPPORT_DANE*/ + + + /************************************************* ************************************************** * Stand-alone test program * @@ -3096,7 +3239,7 @@ return yield; int main(int argc, char **cargv) { host_item h; -int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A; +int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A | HOST_FIND_BY_AAAA; BOOL byname = FALSE; BOOL qualify_single = TRUE; BOOL search_parents = FALSE; @@ -3138,15 +3281,15 @@ while (Ufgets(buffer, 256, stdin) != NULL) if (Ustrcmp(buffer, "byname") == 0) byname = TRUE; else if (Ustrcmp(buffer, "no_byname") == 0) byname = FALSE; - else if (Ustrcmp(buffer, "a_only") == 0) whichrrs = HOST_FIND_BY_A; + else if (Ustrcmp(buffer, "a_only") == 0) whichrrs = HOST_FIND_BY_A | HOST_FIND_BY_AAAA; else if (Ustrcmp(buffer, "mx_only") == 0) whichrrs = HOST_FIND_BY_MX; else if (Ustrcmp(buffer, "srv_only") == 0) whichrrs = HOST_FIND_BY_SRV; else if (Ustrcmp(buffer, "srv+a") == 0) - whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_A; + whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_A | HOST_FIND_BY_AAAA; else if (Ustrcmp(buffer, "srv+mx") == 0) whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX; else if (Ustrcmp(buffer, "srv+mx+a") == 0) - whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX | HOST_FIND_BY_A; + whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX | HOST_FIND_BY_A | HOST_FIND_BY_AAAA; else if (Ustrcmp(buffer, "qualify_single") == 0) qualify_single = TRUE; else if (Ustrcmp(buffer, "no_qualify_single") == 0) qualify_single = FALSE; else if (Ustrcmp(buffer, "search_parents") == 0) search_parents = TRUE; @@ -3154,9 +3297,9 @@ while (Ufgets(buffer, 256, stdin) != NULL) else if (Ustrcmp(buffer, "request_dnssec") == 0) request_dnssec = TRUE; else if (Ustrcmp(buffer, "no_request_dnssec") == 0) request_dnssec = FALSE; else if (Ustrcmp(buffer, "require_dnssec") == 0) require_dnssec = TRUE; - else if (Ustrcmp(buffer, "no_reqiret_dnssec") == 0) require_dnssec = FALSE; + else if (Ustrcmp(buffer, "no_require_dnssec") == 0) require_dnssec = FALSE; else if (Ustrcmp(buffer, "test_harness") == 0) - running_in_test_harness = !running_in_test_harness; + f.running_in_test_harness = !f.running_in_test_harness; else if (Ustrcmp(buffer, "ipv6") == 0) disable_ipv6 = !disable_ipv6; else if (Ustrcmp(buffer, "res_debug") == 0) { @@ -3175,6 +3318,7 @@ while (Ufgets(buffer, 256, stdin) != NULL) else { int flags = whichrrs; + dnssec_domains d; h.name = buffer; h.next = NULL; @@ -3187,16 +3331,21 @@ while (Ufgets(buffer, 256, stdin) != NULL) if (qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE; if (search_parents) flags |= HOST_FIND_SEARCH_PARENTS; + d.request = request_dnssec ? &h.name : NULL; + d.require = require_dnssec ? &h.name : NULL; + rc = byname ? host_find_byname(&h, NULL, flags, &fully_qualified_name, TRUE) : host_find_bydns(&h, NULL, flags, US"smtp", NULL, NULL, - request_dnssec ? &h.name : NULL, - require_dnssec ? &h.name : NULL, - &fully_qualified_name, NULL); + &d, &fully_qualified_name, NULL); - if (rc == HOST_FIND_FAILED) printf("Failed\n"); - else if (rc == HOST_FIND_AGAIN) printf("Again\n"); - else if (rc == HOST_FOUND_LOCAL) printf("Local\n"); + switch (rc) + { + case HOST_FIND_FAILED: printf("Failed\n"); break; + case HOST_FIND_AGAIN: printf("Again\n"); break; + case HOST_FIND_SECURITY: printf("Security\n"); break; + case HOST_FOUND_LOCAL: printf("Local\n"); break; + } } printf("\n> "); @@ -3206,7 +3355,6 @@ printf("Testing host_aton\n"); printf("> "); while (Ufgets(buffer, 256, stdin) != NULL) { - int i; int x[4]; int len = Ustrlen(buffer); @@ -3217,7 +3365,7 @@ while (Ufgets(buffer, 256, stdin) != NULL) len = host_aton(buffer, x); printf("length = %d ", len); - for (i = 0; i < len; i++) + for (int i = 0; i < len; i++) { printf("%04x ", (x[i] >> 16) & 0xffff); printf("%04x ", x[i] & 0xffff);