diff options
| -rw-r--r-- | source4/libcli/resolve/dns_ex.c | 399 |
1 files changed, 238 insertions, 161 deletions
diff --git a/source4/libcli/resolve/dns_ex.c b/source4/libcli/resolve/dns_ex.c index 8f21b7fde5..60e9afda37 100644 --- a/source4/libcli/resolve/dns_ex.c +++ b/source4/libcli/resolve/dns_ex.c @@ -5,6 +5,7 @@ Copyright (C) Andrew Tridgell 2005 Copyright (C) Stefan Metzmacher 2008 + Copyright (C) Matthieu Patou 2011 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -76,68 +77,153 @@ static int dns_ex_destructor(struct dns_ex_state *state) return 0; } -/* - the blocking child -*/ -static void run_child_dns_lookup(struct dns_ex_state *state, int fd) +static uint32_t count_dns_rr(struct rk_resource_record *head, unsigned record_type) { - struct rk_dns_reply *reply; - struct rk_resource_record *rr; uint32_t count = 0; - uint32_t srv_valid = 0; - struct rk_resource_record **srv_rr; - uint32_t addrs_valid = 0; - struct rk_resource_record **addrs_rr; - struct rk_dns_reply **srv_replies = NULL; - char *addrs; - bool first; - uint32_t i; - bool do_srv = (state->flags & RESOLVE_NAME_FLAG_DNS_SRV); + struct rk_resource_record *rr; - if (strchr(state->name.name, '.') && state->name.name[strlen(state->name.name)-1] != '.') { - /* we are asking for a fully qualified name, but the - name doesn't end in a '.'. We need to prevent the - DNS library trying the search domains configured in - resolv.conf */ - state->name.name = talloc_strdup_append(discard_const_p(char, state->name.name), - "."); + for (rr=head; rr; rr=rr->next) { + + /* we are only interested in the IN class */ + if (rr->class != rk_ns_c_in) { + continue; + } + + /* we are only interested by requested record */ + if (rr->type != record_type) { + continue; + } + + switch(record_type) { + case rk_ns_t_srv: + + /* verify we actually have a SRV record here */ + if (!rr->u.srv) { + continue; + } + + /* Verify we got a port */ + if (rr->u.srv->port == 0) { + continue; + } + count++; + break; + case rk_ns_t_a: + case rk_ns_t_aaaa: + /* verify we actually have a record here */ + if (!rr->u.data) { + continue; + } + count++; + break; + default: + count++; + break; + } + } + + return count; +} + +struct dns_records_container { + char **list; + uint32_t count; +}; + +static char* rr_to_string(TALLOC_CTX *mem_ctx, + struct rk_resource_record *rr, + uint16_t port) +{ + char addrstr[INET6_ADDRSTRLEN]; + char *addr; + + switch (rr->type) { + case rk_ns_t_a: + if (inet_ntop(AF_INET, rr->u.a, + addrstr, sizeof(addrstr)) == NULL) { + return NULL; + } + break; +#ifdef HAVE_IPV6 + case rk_ns_t_aaaa: + if (inet_ntop(AF_INET6, (struct in6_addr *)rr->u.data, + addrstr, sizeof(addrstr)) == NULL) { + return NULL; + } + break; +#endif + default: + return NULL; } + addr = talloc_asprintf(mem_ctx, "%s@%u/%s", addrstr, + port, rr->domain); + + return addr; +} + +static struct dns_records_container get_a_aaaa_records(TALLOC_CTX *mem_ctx, + const char* name, + int port) +{ + struct rk_dns_reply *reply, *reply2, *rep, *tmp[3]; + struct rk_resource_record *rr; + struct dns_records_container ret; + char **addrs = NULL; + uint32_t count, count2, total; + uint32_t i; + + memset(&ret, 0, sizeof(struct dns_records_container)); /* this is the blocking call we are going to lots of trouble - to avoid in the parent */ - reply = rk_dns_lookup(state->name.name, do_srv?"SRV":"A"); + to avoid them in the parent */ + reply = rk_dns_lookup(name, "AAAA"); + if (!reply) { - goto done; + return ret; } - if (do_srv) { - rk_dns_srv_order(reply); - } + count = count_dns_rr(reply->head, rk_ns_t_aaaa); + count2 = count_dns_rr(reply->head, rk_ns_t_a); - /* Loop over all returned records and pick the "srv" records */ - for (rr=reply->head; rr; rr=rr->next) { - /* we are only interested in the IN class */ - if (rr->class != rk_ns_c_in) { - continue; + if (!count2) { + /* + * DNS server didn't returned A when asked for AAAA records. + * Most of the server do it, let's ask for A specificaly. + */ + reply2 = rk_dns_lookup(name, "A"); + + if (!reply2) { + return ret; } - if (do_srv) { - /* we are only interested in SRV records */ - if (rr->type != rk_ns_t_srv) { - continue; - } + count2 = count_dns_rr(reply2->head, rk_ns_t_a); + } else { + reply2 = NULL; + } - /* verify we actually have a SRV record here */ - if (!rr->u.srv) { - continue; - } + count += count2; - /* Verify we got a port */ - if (rr->u.srv->port == 0) { + if (count == 0) { + goto done; + } + + addrs = talloc_zero_array(mem_ctx, char*, count); + total = 0; + + tmp[0] = reply; + tmp[1] = reply2; + tmp[2] = NULL; + + /* Loop over all returned records and pick the records */ + for (i=0; tmp[i] != NULL; i++) { + rep = tmp[i]; + for (rr=rep->head; rr; rr=rr->next) { + /* we are only interested in the IN class */ + if (rr->class != rk_ns_c_in) { continue; } - } else { - /* we are only interested in A or AAAA records */ + + /* we are only interested in A and AAAA records */ if (rr->type != rk_ns_t_a && rr->type != rk_ns_t_aaaa) { continue; } @@ -146,105 +232,138 @@ static void run_child_dns_lookup(struct dns_ex_state *state, int fd) if (!rr->u.data) { continue; } + rr_to_string(mem_ctx, rr, port); + addrs[total] = rr_to_string(mem_ctx, rr, port); + if (addrs[total]) { + total++; + } } - count++; } - - if (count == 0) { - goto done; + if (total) { + ret.count = total; + ret.list = addrs; } - srv_rr = talloc_zero_array(state, - struct rk_resource_record *, - count); - if (!srv_rr) { - goto done; - } +done: + if (reply != NULL) + rk_dns_free_data(reply); - addrs_rr = talloc_zero_array(state, - struct rk_resource_record *, - count); - if (!addrs_rr) { - goto done; + if (reply2 != NULL) + rk_dns_free_data(reply2); + + return ret; +} + +static struct dns_records_container get_srv_records(TALLOC_CTX *mem_ctx, + const char* name) +{ + struct rk_dns_reply *reply; + struct rk_resource_record *rr; + struct dns_records_container ret; + char **addrs = NULL; + uint32_t count, total; + + memset(&ret, 0, sizeof(struct dns_records_container)); + /* this is the blocking call we are going to lots of trouble + to avoid them in the parent */ + reply = rk_dns_lookup(name, "SRV"); + + if (!reply) { + return ret; } - srv_replies = talloc_zero_array(state, - struct rk_dns_reply *, - count); - if (!srv_replies) { + rk_dns_srv_order(reply); + count = count_dns_rr(reply->head, rk_ns_t_srv); + + total = 0; + if (count == 0) { goto done; } /* Loop over all returned records and pick the records */ - for (rr=reply->head;rr;rr=rr->next) { + for (rr=reply->head; rr; rr=rr->next) { + struct dns_records_container c; + char* tmp_str; /* we are only interested in the IN class */ if (rr->class != rk_ns_c_in) { continue; } - if (do_srv) { - /* we are only interested in SRV records */ - if (rr->type != rk_ns_t_srv) { - continue; - } + /* we are only interested in SRV records */ + if (rr->type != rk_ns_t_srv) { + continue; + } - /* verify we actually have a srv record here */ - if (!rr->u.srv) { - continue; - } + /* verify we actually have a srv record here */ + if (!rr->u.srv) { + continue; + } - /* Verify we got a port */ - if (rr->u.srv->port == 0) { - continue; - } + /* Verify we got a port */ + if (rr->u.srv->port == 0) { + continue; + } + + tmp_str = rr->u.srv->target; + if (strchr(tmp_str, '.') && tmp_str[strlen(tmp_str)-1] != '.') { + /* we are asking for a fully qualified name, but the + name doesn't end in a '.'. We need to prevent the + DNS library trying the search domains configured in + resolv.conf */ + tmp_str = talloc_asprintf(mem_ctx, "%s.", tmp_str); + } - srv_rr[srv_valid] = rr; - srv_valid++; + c = get_a_aaaa_records(mem_ctx, tmp_str, rr->u.srv->port); + total += c.count; + if (addrs == NULL) { + addrs = c.list; } else { - /* we are only interested in A or AAAA records */ - if (rr->type != rk_ns_t_a && rr->type != rk_ns_t_aaaa) { - continue; - } + unsigned j; - /* verify we actually have a record record here */ - if (!rr->u.data) { - continue; + addrs = talloc_realloc(mem_ctx, addrs, char*, total); + for (j=0; j < c.count; j++) { + addrs[total - j] = talloc_steal(addrs, c.list[j]); } - - addrs_rr[addrs_valid] = rr; - addrs_valid++; } } - for (i=0; i < srv_valid; i++) { - srv_replies[i] = rk_dns_lookup(srv_rr[i]->u.srv->target, "A"); - if (srv_replies[i] == NULL) - continue; + if (total) { + ret.count = total; + ret.list = addrs; + } - /* Add first A record to addrs_rr */ - for (rr=srv_replies[i]->head;rr;rr=rr->next) { - if (rr->class != rk_ns_c_in) { - continue; - } - /* we are only interested in A or AAAA records */ - if (rr->type != rk_ns_t_a && rr->type != rk_ns_t_aaaa) { - continue; - } +done: + if (reply != NULL) + rk_dns_free_data(reply); - /* verify we actually have a record here */ - if (!rr->u.data) { - continue; - } + return ret; +} +/* + the blocking child +*/ +static void run_child_dns_lookup(struct dns_ex_state *state, int fd) +{ + bool first; + bool do_srv = (state->flags & RESOLVE_NAME_FLAG_DNS_SRV); + struct dns_records_container c; + char* addrs = NULL; + unsigned int i; - addrs_rr[i] = rr; - addrs_valid++; - break; - } + if (strchr(state->name.name, '.') && state->name.name[strlen(state->name.name)-1] != '.') { + /* we are asking for a fully qualified name, but the + name doesn't end in a '.'. We need to prevent the + DNS library trying the search domains configured in + resolv.conf */ + state->name.name = talloc_strdup_append(discard_const_p(char, state->name.name), + "."); } - if (addrs_valid == 0) { - goto done; + + if (do_srv) { + c = get_srv_records(state, state->name.name); + } else { + c = get_a_aaaa_records(state, state->name.name, state->port); } addrs = talloc_strdup(state, ""); @@ -252,62 +371,20 @@ static void run_child_dns_lookup(struct dns_ex_state *state, int fd) goto done; } first = true; - for (i=0; i < addrs_valid; i++) { - uint16_t port; - char addrstr[INET6_ADDRSTRLEN]; - - if (!addrs_rr[i]) { - continue; - } - - if (srv_rr[i] && - (state->flags & RESOLVE_NAME_FLAG_OVERWRITE_PORT)) { - port = srv_rr[i]->u.srv->port; - } else { - port = state->port; - } - switch (addrs_rr[i]->type) { - case rk_ns_t_a: - if (inet_ntop(AF_INET, addrs_rr[i]->u.a, - addrstr, sizeof(addrstr)) == NULL) { - continue; - } - break; -#ifdef HAVE_IPV6 - case rk_ns_t_aaaa: - if (inet_ntop(AF_INET6, (struct in6_addr *)addrs_rr[i]->u.data, - addrstr, sizeof(addrstr)) == NULL) { - continue; - } - break; -#endif - default: - continue; - } - - addrs = talloc_asprintf_append_buffer(addrs, "%s%s@%u/%s", - first?"":",", - addrstr, - port, - addrs_rr[i]->domain); - if (!addrs) { - goto done; - } + for (i=0; i < c.count; i++) { + addrs = talloc_asprintf_append_buffer(addrs, "%s%s", + first?"":",", + c.list[i]); first = false; } if (addrs) { + DEBUG(11, ("Addrs = %s\n", addrs)); write(fd, addrs, talloc_get_size(addrs)); } done: - if (reply != NULL) - rk_dns_free_data(reply); - for (i=0; i < srv_valid; i++) { - if (srv_replies[i] != NULL) - rk_dns_free_data(srv_replies[i]); - } close(fd); } |