Fixed the --interface option to work with IPv6 connections on glibc

systems supporting getifaddrs(). Also fixed a problem where an IPv6
address could be chosen instead of an IPv4 one for --interface when it
involved a name lookup.

1 files changed, 59 insertions, 3 deletions

diff --git a/lib/if2ip.c b/lib/if2ip.c
index 94a09c11e..a54050040 100644
--- a/lib/if2ip.c
+++ b/lib/if2ip.c
@@ -42,6 +42,60 @@
     !defined(__AMIGA__) && !defined(__minix) && !defined(__SYMBIAN32__) && \
     !defined(__WATCOMC__)
 
+#if defined(HAVE_GETIFADDRS)
+
+/*
+ * glibc provides getifaddrs() to provide a list of all interfaces and their
+ * addresses.
+ */
+
+#include <ifaddrs.h>
+
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#ifdef HAVE_NETINET_IN_H
+#include <netinet/in.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+
+#include "inet_ntop.h"
+#include "strequal.h"
+
+char *Curl_if2ip(int af, const char *interface, char *buf, int buf_size)
+{
+  struct ifaddrs *iface, *head;
+  char *ip=NULL;
+
+  if (getifaddrs(&head) >= 0) {
+    for (iface=head; iface != NULL; iface=iface->ifa_next) {
+      if ((iface->ifa_addr->sa_family == af) &&
+          curl_strequal(iface->ifa_name, interface)) {
+        void *addr;
+	char scope[12]="";
+        if (af == AF_INET6) {
+          unsigned int scopeid;
+          addr = &((struct sockaddr_in6 *)iface->ifa_addr)->sin6_addr;
+	  /* Include the scope of this interface as part of the address */
+          scopeid = ((struct sockaddr_in6 *)iface->ifa_addr)->sin6_scope_id;
+          if (scopeid)
+	    snprintf(scope, sizeof(scope), "%%%u", scopeid);
+	} else
+          addr = &((struct sockaddr_in *)iface->ifa_addr)->sin_addr;
+        ip = (char *) Curl_inet_ntop(af, addr, buf, buf_size);
+	Curl_strlcat(buf, scope, buf_size);
+	break;
+      }
+    }
+    freeifaddrs(head);
+  }
+  return ip;
+}
+
+#else
+
 #ifdef HAVE_SYS_SOCKET_H
 #include <sys/socket.h>
 #endif
@@ -83,12 +137,12 @@
 
 #define SYS_ERROR -1
 
-char *Curl_if2ip(const char *interface, char *buf, int buf_size)
+char *Curl_if2ip(int af, const char *interface, char *buf, int buf_size)
 {
   int dummy;
   char *ip=NULL;
 
-  if(!interface)
+  if(!interface || (af != AF_INET))
     return NULL;
 
   dummy = socket(AF_INET, SOCK_STREAM, 0);
@@ -124,11 +178,13 @@ char *Curl_if2ip(const char *interface, char *buf, int buf_size)
   }
   return ip;
 }
+#endif
 
 /* -- end of if2ip() -- */
 #else
-char *Curl_if2ip(const char *interf, char *buf, int buf_size)
+char *Curl_if2ip(int af, const char *interf, char *buf, int buf_size)
 {
+    (void) af;
     (void) interf;
     (void) buf;
     (void) buf_size;