Fixed: [PATCH 2/3] uhttpd URL-codec enhancements.

My apologies, the 2nd of those patches had a syntax error -- that's what
I get for making a last-minute edit, even to the comments, without
testing! :-p

Here is the corrected patch.

-- David

From d259cff104d2084455476b82e92a3a27524f4263 Mon Sep 17 00:00:00 2001
From: David Favro <openwrt@meta-dynamic.com>
Date: Fri, 27 Apr 2012 14:17:52 -0400
Subject: [PATCH] uhttpd URL-codec enhancements.

* uh_urlencode() and uh_urldecode() now return an error condition for
  buffer-overflow and malformed-encoding rather than normal return with corrupt
  or truncated data.  As HTTP request processing is currently implemented, this
  causes a 404 HTTP status returned to the client, while 400 is more
  appropriate.

* Exposed urlencode() to Lua.

* Lua's uhttpd.urlencode() and .urldecode() now raise an error condition for
  buffer-overflow and malformed-encoding rather than normal return with
  incorrect data.

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@31570 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 21 insertions, 3 deletions

diff --git a/package/uhttpd/src/uhttpd-lua.c b/package/uhttpd/src/uhttpd-lua.c
index c2efe3384..a140dc2f2 100644
--- a/package/uhttpd/src/uhttpd-lua.c
+++ b/package/uhttpd/src/uhttpd-lua.c
@@ -108,19 +108,34 @@ static int uh_lua_sendc(lua_State *L)
 	return uh_lua_send_common(L, 1);
 }
 
-static int uh_lua_urldecode(lua_State *L)
+static int uh_lua_str2str(lua_State *L, int (*xlate_func) (char *, int, const char *, int))
 {
-	size_t inlen, outlen;
+	size_t inlen;
+	int outlen;
 	const char *inbuf;
 	char outbuf[UH_LIMIT_MSGHEAD];
 
 	inbuf = luaL_checklstring(L, 1, &inlen);
-	outlen = uh_urldecode(outbuf, sizeof(outbuf), inbuf, inlen);
+	outlen = (* xlate_func)(outbuf, sizeof(outbuf), inbuf, inlen);
+	if( outlen < 0 )
+		luaL_error( L, "%s on URL-encode codec",
+			(outlen==-1) ? "buffer overflow" : "malformed string" );
 
 	lua_pushlstring(L, outbuf, outlen);
 	return 1;
 }
 
+static int uh_lua_urldecode(lua_State *L)
+{
+	return uh_lua_str2str( L, uh_urldecode );
+}
+
+
+static int uh_lua_urlencode(lua_State *L)
+{
+	return uh_lua_str2str( L, uh_urlencode );
+}
+
 
 lua_State * uh_lua_init(const char *handler)
 {
@@ -146,6 +161,9 @@ lua_State * uh_lua_init(const char *handler)
 	lua_pushcfunction(L, uh_lua_urldecode);
 	lua_setfield(L, -2, "urldecode");
 
+	lua_pushcfunction(L, uh_lua_urlencode);
+	lua_setfield(L, -2, "urlencode");
+
 	/* _G.uhttpd = { ... } */
 	lua_setfield(L, LUA_GLOBALSINDEX, "uhttpd");