[mms-lib] Workaround for broken MMS proxy IP address. JB#38990

Some operators provide IP address of the MMS proxy
prepending zeros to each number shorter then 3 digits,
e.g. "192.168.094.023" instead of "192.168.94.23".
That may look nicer but it's actually wrong because
the numbers starting with zeros are interpreted as
octal numbers. In the example above 023 actually means
16 and 094 is not a valid number at all.

In addition to publishing these broken settings on their
web sites, some of the operators send them over the air,
in which case we can't even blame the user for entering
an invalid IP address. We better be prepared to deal with
those.

Since nobody in the world seems to be actually using the
octal notation to write an IP address, let's remove the
leading zeros if we find them in the host part of the MMS
proxy URL.

mms-lib/src/mms_task_http.c

@@ -20,6 +20,8 @@
 
 #include <gutil_misc.h>
 
+#include <ctype.h>
+
 #ifndef _WIN32
 #  include <sys/ioctl.h>
 #  include <arpa/inet.h>
@@ -178,6 +180,46 @@ mms_http_create_session(
         SoupURI* proxy_uri = mms_http_uri_parse(conn->mmsproxy);
         if (proxy_uri) {
             GDEBUG("MMS proxy %s", conn->mmsproxy);
+            if (proxy_uri->host[0] == '0' || strstr(proxy_uri->host, ".0")) {
+                /*
+                 * Some operators provide IP address of the MMS proxy
+                 * prepending zeros to each number shorter then 3 digits,
+                 * e.g. "192.168.094.023" instead of "192.168.94.23".
+                 * That may look nicer but it's actually wrong because
+                 * the numbers starting with zeros are interpreted as
+                 * octal numbers. In the example above 023 actually means
+                 * 16 and 094 is not a valid number at all.
+                 *
+                 * In addition to publishing these broken settings on their
+                 * web sites, some of the operators send them over the air,
+                 * in which case we can't even blame the user for entering
+                 * an invalid IP address. We better be prepared to deal with
+                 * those.
+                 *
+                 * Since nobody in the world seems to be actually using the
+                 * octal notation to write an IP address, let's remove the
+                 * leading zeros if we find them in the host part of the MMS
+                 * proxy URL.
+                 */
+                char* host;
+                char** parts = g_strsplit(proxy_uri->host, ".", -1);
+                guint count = g_strv_length(parts);
+                if (count == 4) {
+                    char** ptr = parts;
+                    while (*ptr) {
+                        char* part = *ptr;
+                        while (part[0] == '0' && isdigit(part[1])) {
+                            memmove(part, part+1, strlen(part));
+                        }
+                        *ptr++ = part;
+                    }
+                    host = g_strjoinv(".", parts);
+                    GDEBUG("MMS proxy host %s => %s", proxy_uri->host, host);
+                    soup_uri_set_host(proxy_uri, host);
+                    g_free(host);
+                }
+                g_strfreev(parts);
+            }
             g_object_set(session, SOUP_SESSION_PROXY_URI, proxy_uri, NULL);
             soup_uri_free(proxy_uri);
         }
@@ -266,7 +308,9 @@ mms_task_http_receive_progress(
     MMSTaskHttpPriv* priv = http->priv;
     MMSHttpTransfer* tx = priv->tx;
     if (tx) {
-        GASSERT(tx->bytes_received <= tx->bytes_to_receive);
+        /* Some operators don't provide Content-Length */
+        GASSERT(!tx->bytes_to_receive ||
+            tx->bytes_received <= tx->bytes_to_receive);
         mms_transfer_list_transfer_receive_progress(http->transfers,
             http->task.id, priv->transfer_type, tx->bytes_received,
             tx->bytes_to_receive);