Refactor dns lookups to reuse the code

overlay_link.c

@@ -29,6 +29,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include "keyring.h"
 #include "strbuf_helpers.h"
 #include "route_link.h"
+#include "socket.h"
 
 int set_reachable(struct subscriber *subscriber, 
   struct network_destination *destination, struct subscriber *next_hop,
@@ -80,29 +81,6 @@ int set_reachable(struct subscriber *subscriber,
   return 1;
 }
 
-static int resolve_name(const char *name, struct in_addr *addr){
-  // TODO this can block, move to worker thread.
-  IN();
-  int ret=0;
-  struct addrinfo hint={
-    .ai_family=AF_INET,
-  };
-  struct addrinfo *addresses=NULL;
-  if (getaddrinfo(name, NULL, &hint, &addresses))
-    RETURN(WHYF("Failed to resolve %s",name));
-  
-  if (addresses->ai_addr->sa_family==AF_INET){
-    *addr = ((struct sockaddr_in *)addresses->ai_addr)->sin_addr;
-    DEBUGF(overlayrouting, "Resolved %s into %s", name, inet_ntoa(*addr));
-    
-  }else
-    ret=WHY("Ignoring non IPv4 address");
-  
-  freeaddrinfo(addresses);
-  RETURN(ret);
-  OUT();
-}
-
 // load a unicast address from configuration
 struct network_destination *load_subscriber_address(struct subscriber *subscriber)
 {
@@ -123,19 +101,17 @@ struct network_destination *load_subscriber_address(struct subscriber *subscribe
   }
   struct socket_address addr;
   bzero(&addr, sizeof(addr));
-  addr.addrlen = sizeof(addr.inet);
-  addr.inet.sin_family = AF_INET;
-  addr.inet.sin_addr = hostc->address;
-  addr.inet.sin_port = htons(hostc->port);
-  if (addr.inet.sin_addr.s_addr==INADDR_NONE){
-    if (interface || overlay_interface_get_default()){
-      if (resolve_name(hostc->host, &addr.inet.sin_addr))
-	return NULL;
-    }else{
-      // interface isnt up yet
+  if (hostc->address.s_addr == INADDR_NONE){
+    if (socket_resolve_name(AF_INET, hostc->host, NULL, &addr)==-1){
+      // Perhaps the right interface isnt up yet
       return NULL;
     }
+  }else{
+    addr.addrlen = sizeof(addr.inet);
+    addr.inet.sin_family = AF_INET;
+    addr.inet.sin_addr = hostc->address;
   }
+  addr.inet.sin_port = htons(hostc->port);
   DEBUGF(overlayrouting, "Loaded address %s for %s", alloca_socket_address(&addr), alloca_tohex_sid_t(subscriber->sid));
   return create_unicast_destination(&addr, interface);
 }

rhizome_direct_http.c

@@ -472,26 +472,21 @@ void rhizome_direct_http_dispatch(rhizome_direct_sync_request *r)
   DEBUGF(rhizome_tx, "Dispatch size_high=%"PRId64,r->cursor->size_high);
   rhizome_direct_transport_state_http *state = r->transport_specific_state;
 
-  int sock=socket(AF_INET, SOCK_STREAM, 0);
+  struct socket_address addr;
+  bzero(&addr,sizeof(addr));
+
+  if (socket_resolve_name(AF_INET, state->host, NULL, &addr)==-1){
+    DEBUGF(rhizome_tx, "could not resolve hostname");
+    goto end;
+  }
+  addr.inet.sin_port=htons(state->port);
+
+  int sock=socket(addr.addr.sa_family, SOCK_STREAM, 0);
   if (sock==-1) {
     WHY_perror("socket");
     goto end;
   }
 
-  struct hostent *hostent;
-  hostent = gethostbyname(state->host);
-  if (!hostent) {
-    DEBUGF(rhizome_tx, "could not resolve hostname");
-    goto end;
-  }
-
-  struct socket_address addr;
-  bzero(&addr,sizeof(addr));
-  addr.addrlen = sizeof(addr.inet);
-  addr.inet.sin_family = AF_INET;
-  addr.inet.sin_port = htons(state->port);
-  addr.inet.sin_addr = *((struct in_addr *)hostent->h_addr);
-
   if (connect(sock, &addr.addr, addr.addrlen) == -1) {
     WHYF_perror("connect(%s)", alloca_socket_address(&addr));
     close(sock);

socket.c

@@ -21,6 +21,8 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include <stdlib.h>
 #include <assert.h>
 #include <libgen.h>
+#include <sys/socket.h>
+#include <netdb.h>
 
 #include "instance.h"
 #include "str.h"
@@ -354,3 +356,28 @@ ssize_t _recv_message(struct __sourceloc __whence, int fd, struct socket_address
   data.iov[0].iov_len = buflen;
   return _recv_message_frag(__whence, fd, address, ttl, &data);
 }
+
+int socket_resolve_name(int family, const char *name, const char *service, struct socket_address *address){
+  int ret=-1;
+  struct addrinfo hint={
+    .ai_flags = AI_ADDRCONFIG,
+    .ai_family = family,
+  };
+  struct addrinfo *addresses=NULL;
+  if (getaddrinfo(name, service, &hint, &addresses))
+    return WHYF_perror("Failed to resolve %s",name);
+
+  struct addrinfo *p = addresses;
+  while(p){
+    if (p->ai_addrlen < sizeof(address->raw) && (p->ai_addr->sa_family == AF_INET || p->ai_addr->sa_family == AF_INET6)){
+      address->addrlen = p->ai_addrlen;
+      memcpy(&address->addr, p->ai_addr, p->ai_addrlen);
+      ret = 0;
+      break;
+    }
+    p = p->ai_next;
+  }
+
+  freeaddrinfo(addresses);
+  return ret;
+}

socket.h

@@ -61,6 +61,7 @@ int _socket_listen(struct __sourceloc, int sock, int backlog);
 int _socket_set_reuseaddr(struct __sourceloc, int sock, int reuseP);
 int _socket_set_rcvbufsize(struct __sourceloc, int sock, unsigned buffer_size);
 int socket_unlink_close(int sock);
+int socket_resolve_name(int family, const char *name, const char *service, struct socket_address *address);
 
 #define make_local_sockaddr(sockname, fmt,...) _make_local_sockaddr(__WHENCE__, (sockname), (fmt), ##__VA_ARGS__)
 #define esocket(domain, type, protocol)             _esocket(__WHENCE__, (domain), (type), (protocol))