ag/cpython-source-deps
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Import OpenSSL1.1.1k

Browse Source
This commit is contained in:
Steve Dower
2021-03-29 21:47:40 +01:00
parent ae8aba4cbc
commit b439f09b29
104 changed files with 1075 additions and 379 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
crypto/dh/dh_key.c
View File

@@ -1,5 +1,5 @@
/*
* Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
* Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -25,18 +25,45 @@ int DH_generate_key(DH *dh)
return dh->meth->generate_key(dh);
}
/*-
* NB: This function is inherently not constant time due to the
* RFC 5246 (8.1.2) padding style that strips leading zero bytes.
*/
int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
return dh->meth->compute_key(key, pub_key, dh);
int ret = 0, i;
volatile size_t npad = 0, mask = 1;
/* compute the key; ret is constant unless compute_key is external */
if ((ret = dh->meth->compute_key(key, pub_key, dh)) <= 0)
return ret;
/* count leading zero bytes, yet still touch all bytes */
for (i = 0; i < ret; i++) {
mask &= !key[i];
npad += mask;
}
/* unpad key */
ret -= npad;
/* key-dependent memory access, potentially leaking npad / ret */
memmove(key, key + npad, ret);
/* key-dependent memory access, potentially leaking npad / ret */
memset(key + ret, 0, npad);
return ret;
}
int DH_compute_key_padded(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
int rv, pad;
/* rv is constant unless compute_key is external */
rv = dh->meth->compute_key(key, pub_key, dh);
if (rv <= 0)
return rv;
pad = BN_num_bytes(dh->p) - rv;
/* pad is constant (zero) unless compute_key is external */
if (pad > 0) {
memmove(key + pad, key, rv);
memset(key, 0, pad);
@@ -212,7 +239,7 @@ static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
goto err;
}
ret = BN_bn2bin(tmp, key);
ret = BN_bn2binpad(tmp, key, BN_num_bytes(dh->p));
err:
BN_CTX_end(ctx);
BN_CTX_free(ctx);