mirrors/prosody
1
0
Fork 0
mirror of https://github.com/bjc/prosody.git synced 2025-04-03 05:07:42 +03:00
Code Issues Projects Releases Packages Wiki Activity Actions

util.crypto: Use stack space buffers

Browse source 
Removes assumption that LUAL_BUFFERSIZE is known at pre-processing time,
which it is not in Lua 5.3 and 5.4, where it is a computed macro based
on sizeof.

Allocation of stack space is safer and faster, no need to worry about
luaL_prepbuffer failing to allocate memory and skipping free()
This commit is contained in:
Kim Alvefur 2022-07-11 17:01:55 +02:00
parent e12c9a83df
commit e893bbf681
1 changed files with 11 additions and 14 deletions
Download patch file Download diff file Expand all files Collapse all files

25
util-src/crypto.c
View file

@ -434,7 +434,8 @@ static int Lparse_ecdsa_signature(lua_State *L) {
size_t sig_der_len;
const unsigned char *sig_der = (unsigned char*)luaL_checklstring(L, 1, &sig_der_len);
const BIGNUM *r, *s;
luaL_Buffer rb, sb;
unsigned char rb[32];
unsigned char sb[32];
int rlen, slen;
sig = d2i_ECDSA_SIG(NULL, &sig_der, sig_der_len);
@ -449,23 +450,19 @@ static int Lparse_ecdsa_signature(lua_State *L) {
rlen = BN_num_bytes(r);
slen = BN_num_bytes(s);
// COMPAT w/ Lua 5.1
#if LUAL_BUFFERSIZE < 32
#error Configured LUAL_BUFFERSIZE is too small for this operation
#endif
if (rlen > 32 || slen > 32) {
ECDSA_SIG_free(sig);
luaL_error(L, "unexpectedly large signature integers");
}
luaL_buffinit(L, &rb);
BN_bn2bin(r, (unsigned char*)luaL_prepbuffer(&rb));
luaL_addsize(&rb, rlen);
luaL_pushresult(&rb);
luaL_buffinit(L, &sb);
BN_bn2bin(s, (unsigned char*)luaL_prepbuffer(&sb));
luaL_addsize(&sb, slen);
luaL_pushresult(&sb);
BN_bn2bin(r, rb);
BN_bn2bin(s, sb);
ECDSA_SIG_free(sig);
lua_pushlstring(L, (const char*)rb, rlen);
lua_pushlstring(L, (const char*)sb, slen);
return 2;
}