source4/libcli/resolve: Convert away from dns_unmarshall

Use pidl-based DNS routines, avoid hand-marshalling DNS routines
outside of lib/addns.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>

diff --git a/source4/libcli/resolve/dns_ex.c b/source4/libcli/resolve/dns_ex.c
index 822fc456847386ef73ec0d53e18c8e3d5e041ca1..eec37084babd7dbe50a97619e7f9d16611769178 100644 (file)
--- a/source4/libcli/resolve/dns_ex.c
+++ b/source4/libcli/resolve/dns_ex.c
@@ -35,7 +35,9 @@
 #include "system/filesys.h"
 #include "lib/socket/socket.h"
 #include "libcli/composite/composite.h"
+#include "librpc/ndr/libndr.h"
 #include "librpc/gen_ndr/ndr_nbt.h"
+#include "librpc/gen_ndr/ndr_dns.h"
 #include "libcli/resolve/resolve.h"
 #include "lib/util/util_net.h"
 #include "lib/addns/dnsquery.h"
@@ -81,33 +83,37 @@ struct dns_records_container {
        uint32_t count;
 };
 
-static int reply_to_addrs(TALLOC_CTX *mem_ctx, uint32_t *a_num,
-                         char ***cur_addrs, uint32_t total,
-                         struct dns_request *reply, int port)
+static int reply_to_addrs(TALLOC_CTX *mem_ctx,
+                         uint32_t *a_num,
+                         char ***cur_addrs,
+                         uint32_t total,
+                         const struct dns_name_packet *reply,
+                         int port)
 {
-       char addrstr[INET6_ADDRSTRLEN];
-       struct dns_rrec *rr;
-       char **addrs;
-       uint32_t i;
-       const char *addr;
+       struct dns_res_rec *rr = NULL;
+       const char *addr = NULL;
+       char **addrs = NULL;
+       uint16_t i;
 
        /* at most we over-allocate here, but not by much */
-       addrs = talloc_realloc(mem_ctx, *cur_addrs, char *,
-                               total + reply->num_answers);
+       addrs = talloc_realloc(mem_ctx,
+                              *cur_addrs,
+                              char *,
+                              total + reply->ancount);
        if (!addrs) {
                return 0;
        }
        *cur_addrs = addrs;
 
-       for (i = 0; i < reply->num_answers; i++) {
-               rr = reply->answers[i];
+       for (i = 0; i < reply->ancount; i++) {
+               rr = &reply->answers[i];
 
                /* we are only interested in the IN class */
-               if (rr->r_class != DNS_CLASS_IN) {
+               if (rr->rr_class != DNS_CLASS_IN) {
                        continue;
                }
 
-               if (rr->type == QTYPE_NS) {
+               if (rr->rr_type == QTYPE_NS) {
                        /*
                         * After the record for NS will come the A or AAAA
                         * record of the NS.
@@ -116,54 +122,29 @@ static int reply_to_addrs(TALLOC_CTX *mem_ctx, uint32_t *a_num,
                }
 
                /* verify we actually have a record here */
-               if (!rr->data) {
+               if (rr->length == 0) {
                        continue;
                }
 
                /* we are only interested in A and AAAA records */
-               switch (rr->type) {
+               switch (rr->rr_type) {
                case QTYPE_A:
-                       /*
-                        * rr->data will be correctly aligned as it's allocated
-                        * in dns_unmarshall_rr
-                        */
-                       addr = inet_ntop(AF_INET,
-                                        discard_align_p(struct in_addr,
-                                                        rr->data),
-                                        addrstr,
-                                        sizeof(addrstr));
-                       if (addr == NULL) {
-                               continue;
-                       }
+                       addr = rr->rdata.ipv4_record;
                        break;
-               case QTYPE_AAAA:
 #ifdef HAVE_IPV6
-                       /*
-                        * rr->data will be correctly aligned as it's allocated
-                        * in dns_unmarshal_rr
-                        */
-                       addr = inet_ntop(AF_INET6,
-                                        discard_align_p(struct in6_addr,
-                                                        rr->data),
-                                        addrstr,
-                                        sizeof(addrstr));
-#else
-                       addr = NULL;
-#endif
-                       if (addr == NULL) {
-                               continue;
-                       }
+               case QTYPE_AAAA:
+                       addr = rr->rdata.ipv6_record;
                        break;
+#endif
                default:
                        continue;
                }
 
-               addrs[total] = talloc_asprintf(addrs, "%s@%u/%s",
-                                               addrstr, port,
-                                               rr->name->pLabelList->label);
+               addrs[total] = talloc_asprintf(
+                       addrs, "%s@%u/%s", addr, port, rr->name);
                if (addrs[total]) {
                        total++;
-                       if (rr->type == QTYPE_A) {
+                       if (rr->rr_type == QTYPE_A) {
                                (*a_num)++;
                        }
                }
@@ -172,26 +153,28 @@ static int reply_to_addrs(TALLOC_CTX *mem_ctx, uint32_t *a_num,
        return total;
 }
 
-static DNS_ERROR dns_lookup(TALLOC_CTX *mem_ctx, const char* name,
-                           uint16_t q_type, struct dns_request **reply)
+static DNS_ERROR dns_lookup(TALLOC_CTX *mem_ctx,
+                           const char *name,
+                           uint16_t q_type,
+                           struct dns_name_packet **reply)
 {
        int len, rlen;
-       uint8_t *answer;
        bool loop;
-       struct dns_buffer buf;
-       DNS_ERROR err;
+       struct dns_name_packet *packet = NULL;
+       DATA_BLOB blob = {};
+       enum ndr_err_code ndr_err;
 
        /* give space for a good sized answer by default */
-       answer = NULL;
        len = 1500;
        do {
-               answer = talloc_realloc(mem_ctx, answer, uint8_t, len);
-               if (!answer) {
+               bool ok = data_blob_realloc(mem_ctx, &blob, len);
+               if (!ok) {
                        return ERROR_DNS_NO_MEMORY;
                }
-               rlen = res_search(name, DNS_CLASS_IN, q_type, answer, len);
+               rlen = res_search(name, DNS_CLASS_IN, q_type, blob.data, len);
                if (rlen == -1) {
                        if (len >= 65535) {
+                               data_blob_free(&blob);
                                return ERROR_DNS_SOCKET_ERROR;
                        }
                        /* retry once with max packet size */
@@ -205,22 +188,33 @@ static DNS_ERROR dns_lookup(TALLOC_CTX *mem_ctx, const char* name,
                }
        } while(loop);
 
-       buf.data = answer;
-       buf.size = rlen;
-       buf.offset = 0;
-       buf.error = ERROR_DNS_SUCCESS;
+       packet = talloc(mem_ctx, struct dns_name_packet);
+       if (!packet) {
+               data_blob_free(&blob);
+               return ERROR_DNS_NO_MEMORY;
+       }
+
+       ndr_err = ndr_pull_struct_blob(&blob,
+                                      packet,
+                                      packet,
+                                      (ndr_pull_flags_fn_t)
+                                              ndr_pull_dns_name_packet);
+       if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+               data_blob_free(&blob);
+               return ERROR_DNS_INVALID_MESSAGE;
+       }
 
-       err = dns_unmarshall_request(mem_ctx, &buf, reply);
+       *reply = packet;
 
-       TALLOC_FREE(answer);
-       return err;
+       data_blob_free(&blob);
+       return ERROR_DNS_SUCCESS;
 }
 
 static struct dns_records_container get_a_aaaa_records(TALLOC_CTX *mem_ctx,
                                                        const char* name,
                                                        int port)
 {
-       struct dns_request *reply;
+       struct dns_name_packet *reply;
        struct dns_records_container ret;
        char **addrs = NULL;
        uint32_t a_num, total;