Remove an unreasonable parameter limit in parse_cgi_parameters()

The new parameter limit depends on the memory available and
is currently unlikely to be reachable, due to other limits in
both Privoxy and common clients.

So the limit is actually still there, but at least it's no
longer unreasonable, is properly handled, and should be high
enough for anybody.

Reported by Andrew on ijbswa-users@.

diff --git a/cgi.c b/cgi.c
index c55f58f..556aa43 100644 (file)
--- a/cgi.c
+++ b/cgi.c
@@ -1,4 +1,4 @@
-const char cgi_rcs[] = "$Id: cgi.c,v 1.150 2012/03/09 17:55:49 fabiankeil Exp $";
+const char cgi_rcs[] = "$Id: cgi.c,v 1.151 2012/06/08 15:07:53 fabiankeil Exp $";
 /*********************************************************************
  *
  * File        :  $Source: /cvsroot/ijbswa/current/cgi.c,v $
@@ -594,12 +594,36 @@ static struct http_response *dispatch_known_cgi(struct client_state * csp,
 static struct map *parse_cgi_parameters(char *argstring)
 {
    char *p;
-   char *vector[BUFFER_SIZE];
+   char **vector;
    int pairs, i;
    struct map *cgi_params;
 
+   /*
+    * XXX: This estimate is guaranteed to be high enough as we
+    *      let ssplit() ignore empty fields, but also a bit wasteful.
+    *      The same hack is used in get_last_url() so it looks like
+    *      a real solution is needed.
+    */
+   size_t max_segments = strlen(argstring) / 2;
+   if (max_segments == 0)
+   {
+      /*
+       * XXX: If the argstring is empty, there's really
+       *      no point in creating a param list, but currently
+       *      other parts of Privoxy depend on the list's existence.
+       */
+      max_segments = 1;
+   }
+   vector = malloc(max_segments * sizeof(char *));
+
+   if (NULL == vector)
+   {
+      return NULL;
+   }
+
    if (NULL == (cgi_params = new_map()))
    {
+      freez(vector);
       return NULL;
    }
 
@@ -613,9 +637,11 @@ static struct map *parse_cgi_parameters(char *argstring)
       *p = '\0';
    }
 
-   pairs = ssplit(argstring, "&", vector, SZ(vector), 1, 1);
+   pairs = ssplit(argstring, "&", vector, max_segments, 1, 1);
+   assert(pairs != -1);
    if (pairs == -1)
    {
+      freez(vector);
       free_map(cgi_params);
       return NULL;
    }
@@ -627,12 +653,15 @@ static struct map *parse_cgi_parameters(char *argstring)
          *p = '\0';
          if (map(cgi_params, url_decode(vector[i]), 0, url_decode(++p), 0))
          {
+            freez(vector);
             free_map(cgi_params);
             return NULL;
          }
       }
    }
 
+   freez(vector);
+
    return cgi_params;
 
 }