Changeset 0aa70f4 in mainline for uspace/srv/net/dnsrsrv/query.c

Timestamp:

2013-07-19T13:23:00Z (12 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

cd18cd1

Parents:

44c9ef4

Message:

support for IPv6 DNS name resolution (AAAA)
if the desired address family of the DNS query is not explicitly specified, then IPv6 addresses take precendece over IPv4 addresses

File:

• uspace/srv/net/dnsrsrv/query.c (modified) (4 diffs)

uspace/srv/net/dnsrsrv/query.c

@@ -39 +39 @@
 #include <stdlib.h>
 #include <str.h>
-
+#include <net/socket_codes.h>
 #include "dns_msg.h"
 #include "dns_std.h"
@@ -48 +48 @@
 static uint16_t msg_id;
 
-int dns_name2host(const char *name, dns_host_info_t **rinfo)
+static int dns_name_query(const char *name, dns_qtype_t qtype,
+    dns_host_info_t *info)
 {
-        dns_message_t *msg;
-        dns_message_t *amsg;
-        dns_question_t *question;
-        dns_host_info_t *info;
-        char *sname, *cname;
-        size_t eoff;
-        int rc;
-
-        question = calloc(1, sizeof(dns_question_t));
-        if (question == NULL)
-                return ENOMEM;
-
-        question->qname = (char *)name;
-        question->qtype = DTYPE_A;
+        /* Start with the caller-provided name */
+        char *sname = str_dup(name);
+        if (sname == NULL)
+                return ENOMEM;
+        
+        char *qname = str_dup(name);
+        if (qname == NULL) {
+                free(sname);
+                return ENOMEM;
+        }
+        
+        dns_question_t *question = calloc(1, sizeof(dns_question_t));
+        if (question == NULL) {
+                free(qname);
+                free(sname);
+                return ENOMEM;
+        }
+        
+        question->qname = qname;
+        question->qtype = qtype;
         question->qclass = DC_IN;
-
-        msg = dns_message_new();
-        if (msg == NULL)
-                return ENOMEM;
-
-        list_append(&question->msg, &msg->question);
-
+        
+        dns_message_t *msg = dns_message_new();
+        if (msg == NULL) {
+                free(question);
+                free(qname);
+                free(sname);
+                return ENOMEM;
+        }
+        
         msg->id = msg_id++;
         msg->qr = QR_QUERY;
@@ -79 +88 @@
         msg->rd = true;
         msg->ra = false;
-
-        rc = dns_request(msg, &amsg);
+        
+        list_append(&question->msg, &msg->question);
+        
+        dns_message_t *amsg;
+        int rc = dns_request(msg, &amsg);
         if (rc != EOK) {
+                dns_message_destroy(msg);
+                free(sname);
                 return rc;
         }
-
-        /* Start with the caller-provided name */
-        sname = str_dup(name);
-
+        
         list_foreach(amsg->answer, link) {
                 dns_rr_t *rr = list_get_instance(link, dns_rr_t, msg);
-
+                
                 log_msg(LOG_DEFAULT, LVL_DEBUG, " - '%s' %u/%u, dsize %zu",
-                        rr->name, rr->rtype, rr->rclass, rr->rdata_size);
-
-                if (rr->rtype == DTYPE_CNAME && rr->rclass == DC_IN &&
-                    str_cmp(rr->name, sname) == 0) {
+                    rr->name, rr->rtype, rr->rclass, rr->rdata_size);
+                
+                if ((rr->rtype == DTYPE_CNAME) && (rr->rclass == DC_IN) &&
+                    (str_cmp(rr->name, sname) == 0)) {
+                        
                         log_msg(LOG_DEFAULT, LVL_DEBUG, "decode cname (%p, %zu, %zu)",
                             amsg->pdu.data, amsg->pdu.size, rr->roff);
+                        
+                        char *cname;
+                        size_t eoff;
                         rc = dns_name_decode(&amsg->pdu, rr->roff, &cname, &eoff);
                         if (rc != EOK) {
-                                log_msg(LOG_DEFAULT, LVL_DEBUG,
-                                    "error decoding cname");
-                                assert(rc == EINVAL || rc == ENOMEM);
+                                assert((rc == EINVAL) || (rc == ENOMEM));
+                                
+                                log_msg(LOG_DEFAULT, LVL_DEBUG, "error decoding cname");
+                                
                                 dns_message_destroy(msg);
                                 dns_message_destroy(amsg);
+                                free(sname);
+                                
                                 return rc;
                         }
-
+                        
                         log_msg(LOG_DEFAULT, LVL_DEBUG, "name = '%s' "
                             "cname = '%s'", sname, cname);
-
+                        
+                        /* Continue looking for the more canonical name */
                         free(sname);
-                        /* Continue looking for the more canonical name */
                         sname = cname;
                 }
-
-                if (rr->rtype == DTYPE_A && rr->rclass == DC_IN &&
-                        rr->rdata_size == sizeof(uint32_t) &&
-                            str_cmp(rr->name, sname) == 0) {
-
-                        info = calloc(1, sizeof(dns_host_info_t));
-                        if (info == NULL) {
+                
+                if ((qtype == DTYPE_A) && (rr->rtype == DTYPE_A) &&
+                    (rr->rclass == DC_IN) && (rr->rdata_size == sizeof(addr32_t)) &&
+                    (str_cmp(rr->name, sname) == 0)) {
+                        
+                        info->cname = str_dup(rr->name);
+                        if (info->cname == NULL) {
                                 dns_message_destroy(msg);
                                 dns_message_destroy(amsg);
+                                free(sname);
+                                
                                 return ENOMEM;
                         }
-
-                        info->cname = str_dup(rr->name);
+                        
                         inet_addr_set(dns_uint32_t_decode(rr->rdata, rr->rdata_size),
                             &info->addr);
@@ -133 +152 @@
                         dns_message_destroy(msg);
                         dns_message_destroy(amsg);
-                        *rinfo = info;
+                        free(sname);
+                        
                         return EOK;
                 }
-        }
-
+                
+                if ((qtype == DTYPE_AAAA) && (rr->rtype == DTYPE_AAAA) &&
+                    (rr->rclass == DC_IN) && (rr->rdata_size == sizeof(addr128_t)) &&
+                    (str_cmp(rr->name, sname) == 0)) {
+                
+                        info->cname = str_dup(rr->name);
+                        if (info->cname == NULL) {
+                                dns_message_destroy(msg);
+                                dns_message_destroy(amsg);
+                                free(sname);
+                                
+                                return ENOMEM;
+                        }
+                        
+                        addr128_t addr;
+                        dns_addr128_t_decode(rr->rdata, rr->rdata_size, addr);
+                        
+                        inet_addr_set6(addr, &info->addr);
+                        
+                        dns_message_destroy(msg);
+                        dns_message_destroy(amsg);
+                        free(sname);
+                        
+                        return EOK;
+                }
+        }
+        
+        log_msg(LOG_DEFAULT, LVL_DEBUG, "'%s' not resolved, fail", sname);
+        
         dns_message_destroy(msg);
         dns_message_destroy(amsg);
-        log_msg(LOG_DEFAULT, LVL_DEBUG, "'%s' not resolved, fail", sname);
-
+        free(sname);
+        
         return EIO;
+}
+
+int dns_name2host(const char *name, dns_host_info_t **rinfo, uint16_t af)
+{
+        dns_host_info_t *info = calloc(1, sizeof(dns_host_info_t));
+        if (info == NULL)
+                return ENOMEM;
+        
+        int rc;
+        
+        switch (af) {
+        case AF_NONE:
+                rc = dns_name_query(name, DTYPE_AAAA, info);
+                
+                if (rc != EOK)
+                        rc = dns_name_query(name, DTYPE_A, info);
+                
+                break;
+        case AF_INET:
+                rc = dns_name_query(name, DTYPE_A, info);
+                break;
+        case AF_INET6:
+                rc = dns_name_query(name, DTYPE_AAAA, info);
+                break;
+        default:
+                rc = EINVAL;
+        }
+        
+        if (rc == EOK)
+                *rinfo = info;
+        else
+                free(info);
+        
+        return rc;
 }