# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1779717075 -3600
# Node ID af87d31dcae40ae38e5ae4adac8fd9e0d44ce5d4
# Parent  67b68147ed1dea9622f26b1f01e75833f9560d54
util.crypto: Ensure signing parameter is a string

lua_tostring() returns NULL if the specified value is missing or can't become
a string. luaL_checkstring() will raise an error.

We prefer the latter behaviour, otherwise we end up passing NULL to OpenSSL.

diff -r 67b68147ed1d -r af87d31dcae4 util-src/crypto.c
--- a/util-src/crypto.c	Mon May 25 14:44:20 2026 +0100
+++ b/util-src/crypto.c	Mon May 25 14:51:15 2026 +0100
@@ -132,7 +132,7 @@
 	luaL_Buffer sigbuf;
 
 	size_t msg_len;
-	const unsigned char* msg = (unsigned char*)lua_tolstring(L, 2, &msg_len);
+	const unsigned char* msg = (unsigned char*)luaL_checklstring(L, 2, &msg_len);
 
 	size_t sig_len;
 	unsigned char *sig = NULL;