wget: remove IPv6 scope id in Host: field (apache compat)

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 51 insertions, 3 deletions

diff --git a/networking/wget.c b/networking/wget.c
index d518286a4..26b62cc58 100644
--- a/networking/wget.c
+++ b/networking/wget.c
@@ -193,6 +193,42 @@ static ALWAYS_INLINE void progress_meter(int flag UNUSED_PARAM) { }
 #endif
 
 
+/* IPv6 knows scoped address types i.e. link and site local addresses. Link
+ * local addresses can have a scope identifier to specify the
+ * interface/link an address is valid on (e.g. fe80::1%eth0). This scope
+ * identifier is only valid on a single node.
+ *
+ * RFC 4007 says that the scope identifier MUST NOT be sent across the wire,
+ * unless all nodes agree on the semantic. Apache e.g. regards zone identifiers
+ * in the Host header as invalid requests, see
+ * https://issues.apache.org/bugzilla/show_bug.cgi?id=35122
+ */
+static void strip_ipv6_scope_id(char *host)
+{
+        char *scope, *cp;
+
+        /* bbox wget actually handles IPv6 addresses without [], like
+         * wget "http://::1/xxx", but this is not standard.
+         * To save code, _here_ we do not support it. */
+
+        if (host[0] != '[')
+                return; /* not IPv6 */
+
+        scope = strchr(host, '%');
+        if (!scope)
+                return;
+
+        /* Remove the IPv6 zone identifier from the host address */
+        cp = strchr(host, ']');
+        if (!cp || (cp[1] != ':' && cp[1] != '\0')) {
+                /* malformed address (not "[xx]:nn" or "[xx]") */
+                return;
+        }
+
+        /* cp points to "]...", scope points to "%eth0]..." */
+        overlapping_strcpy(scope, cp);
+}
+
 /* Read NMEMB bytes into PTR from STREAM.  Returns the number of bytes read,
  * and a short count if an eof or non-interrupt error is encountered.  */
 static size_t safe_fread(void *ptr, size_t nmemb, FILE *stream)
@@ -655,20 +691,30 @@ int wget_main(int argc UNUSED_PARAM, char **argv)
 #endif
 
         /* TODO: compat issue: should handle "wget URL1 URL2..." */
+
         parse_url(argv[optind], &target);
-        server.host = target.host;
-        server.port = target.port;
 
         /* Use the proxy if necessary */
         use_proxy = (strcmp(proxy_flag, "off") != 0);
         if (use_proxy) {
                 proxy = getenv(target.is_ftp ? "ftp_proxy" : "http_proxy");
-                if (proxy && *proxy) {
+                if (proxy && proxy[0]) {
                         parse_url(proxy, &server);
                 } else {
                         use_proxy = 0;
                 }
         }
+        if (!use_proxy) {
+                server.port = target.port;
+                if (ENABLE_FEATURE_IPV6) {
+                        server.host = xstrdup(target.host);
+                } else {
+                        server.host = target.host;
+                }
+        }
+
+        if (ENABLE_FEATURE_IPV6)
+                strip_ipv6_scope_id(target.host);
 
         /* Guess an output filename, if there was no -O FILE */
         if (!(opt & WGET_OPT_OUTNAME)) {
@@ -862,6 +908,8 @@ However, in real world it was observed that some web servers
                                         parse_url(str, &target);
                                         if (!use_proxy) {
                                                 server.host = target.host;
+                                                /* strip_ipv6_scope_id(target.host); - no! */
+                                                /* we assume remote never gives us IPv6 addr with scope id */
                                                 server.port = target.port;
                                                 free(lsa);
                                                 goto resolve_lsa;