openssl/crypto/kdf/pbkdf2.c
David Makepeace 5a285addbf Added new EVP/KDF API.
Changed PKEY/KDF API to call the new API.
Added wrappers for PKCS5_PBKDF2_HMAC() and EVP_PBE_scrypt() to call the new EVP KDF APIs.
Documentation updated.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6674)
2019-02-13 12:11:49 +01:00

265 lines
7.1 KiB
C

/*
* Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <openssl/hmac.h>
#include <openssl/evp.h>
#include <openssl/kdf.h>
#include "internal/cryptlib.h"
#include "internal/evp_int.h"
#include "kdf_local.h"
static void kdf_pbkdf2_reset(EVP_KDF_IMPL *impl);
static void kdf_pbkdf2_init(EVP_KDF_IMPL *impl);
static int pkcs5_pbkdf2_alg(const char *pass, size_t passlen,
const unsigned char *salt, int saltlen, int iter,
const EVP_MD *digest, unsigned char *key,
size_t keylen);
struct evp_kdf_impl_st {
unsigned char *pass;
size_t pass_len;
unsigned char *salt;
size_t salt_len;
int iter;
const EVP_MD *md;
};
static EVP_KDF_IMPL *kdf_pbkdf2_new(void)
{
EVP_KDF_IMPL *impl;
impl = OPENSSL_zalloc(sizeof(*impl));
if (impl == NULL) {
KDFerr(KDF_F_KDF_PBKDF2_NEW, ERR_R_MALLOC_FAILURE);
return NULL;
}
kdf_pbkdf2_init(impl);
return impl;
}
static void kdf_pbkdf2_free(EVP_KDF_IMPL *impl)
{
kdf_pbkdf2_reset(impl);
OPENSSL_free(impl);
}
static void kdf_pbkdf2_reset(EVP_KDF_IMPL *impl)
{
OPENSSL_free(impl->salt);
OPENSSL_clear_free(impl->pass, impl->pass_len);
memset(impl, 0, sizeof(*impl));
kdf_pbkdf2_init(impl);
}
static void kdf_pbkdf2_init(EVP_KDF_IMPL *impl)
{
impl->iter = PKCS5_DEFAULT_ITER;
impl->md = EVP_sha1();
}
static int pbkdf2_set_membuf(unsigned char **buffer, size_t *buflen,
const unsigned char *new_buffer,
size_t new_buflen)
{
if (new_buffer == NULL)
return 1;
OPENSSL_clear_free(*buffer, *buflen);
if (new_buflen > 0) {
*buffer = OPENSSL_memdup(new_buffer, new_buflen);
} else {
*buffer = OPENSSL_malloc(1);
}
if (*buffer == NULL) {
KDFerr(KDF_F_PBKDF2_SET_MEMBUF, ERR_R_MALLOC_FAILURE);
return 0;
}
*buflen = new_buflen;
return 1;
}
static int kdf_pbkdf2_ctrl(EVP_KDF_IMPL *impl, int cmd, va_list args)
{
int iter;
const unsigned char *p;
size_t len;
const EVP_MD *md;
switch (cmd) {
case EVP_KDF_CTRL_SET_PASS:
p = va_arg(args, const unsigned char *);
len = va_arg(args, size_t);
return pbkdf2_set_membuf(&impl->pass, &impl->pass_len, p, len);
case EVP_KDF_CTRL_SET_SALT:
p = va_arg(args, const unsigned char *);
len = va_arg(args, size_t);
return pbkdf2_set_membuf(&impl->salt, &impl->salt_len, p, len);
case EVP_KDF_CTRL_SET_ITER:
iter = va_arg(args, int);
if (iter < 1)
return 0;
impl->iter = iter;
return 1;
case EVP_KDF_CTRL_SET_MD:
md = va_arg(args, const EVP_MD *);
if (md == NULL)
return 0;
impl->md = md;
return 1;
default:
return -2;
}
}
static int kdf_pbkdf2_ctrl_str(EVP_KDF_IMPL *impl, const char *type,
const char *value)
{
if (value == NULL) {
KDFerr(KDF_F_KDF_PBKDF2_CTRL_STR, KDF_R_VALUE_MISSING);
return 0;
}
if (strcmp(type, "pass") == 0)
return kdf_str2ctrl(impl, kdf_pbkdf2_ctrl, EVP_KDF_CTRL_SET_PASS,
value);
if (strcmp(type, "hexpass") == 0)
return kdf_hex2ctrl(impl, kdf_pbkdf2_ctrl, EVP_KDF_CTRL_SET_PASS,
value);
if (strcmp(type, "salt") == 0)
return kdf_str2ctrl(impl, kdf_pbkdf2_ctrl, EVP_KDF_CTRL_SET_SALT,
value);
if (strcmp(type, "hexsalt") == 0)
return kdf_hex2ctrl(impl, kdf_pbkdf2_ctrl, EVP_KDF_CTRL_SET_SALT,
value);
if (strcmp(type, "iter") == 0)
return call_ctrl(kdf_pbkdf2_ctrl, impl, EVP_KDF_CTRL_SET_ITER,
atoi(value));
if (strcmp(type, "digest") == 0)
return kdf_md2ctrl(impl, kdf_pbkdf2_ctrl, EVP_KDF_CTRL_SET_MD, value);
return -2;
}
static int kdf_pbkdf2_derive(EVP_KDF_IMPL *impl, unsigned char *key,
size_t keylen)
{
if (impl->pass == NULL) {
KDFerr(KDF_F_KDF_PBKDF2_DERIVE, KDF_R_MISSING_PASS);
return 0;
}
if (impl->salt == NULL) {
KDFerr(KDF_F_KDF_PBKDF2_DERIVE, KDF_R_MISSING_SALT);
return 0;
}
return pkcs5_pbkdf2_alg((char *)impl->pass, impl->pass_len,
impl->salt, impl->salt_len, impl->iter,
impl->md, key, keylen);
}
const EVP_KDF_METHOD pbkdf2_kdf_meth = {
EVP_KDF_PBKDF2,
kdf_pbkdf2_new,
kdf_pbkdf2_free,
kdf_pbkdf2_reset,
kdf_pbkdf2_ctrl,
kdf_pbkdf2_ctrl_str,
NULL,
kdf_pbkdf2_derive
};
/*
* This is an implementation of PKCS#5 v2.0 password based encryption key
* derivation function PBKDF2. SHA1 version verified against test vectors
* posted by Peter Gutmann to the PKCS-TNG mailing list.
*/
static int pkcs5_pbkdf2_alg(const char *pass, size_t passlen,
const unsigned char *salt, int saltlen, int iter,
const EVP_MD *digest, unsigned char *key,
size_t keylen)
{
int ret = 0;
unsigned char digtmp[EVP_MAX_MD_SIZE], *p, itmp[4];
int cplen, j, k, tkeylen, mdlen;
unsigned long i = 1;
HMAC_CTX *hctx_tpl = NULL, *hctx = NULL;
mdlen = EVP_MD_size(digest);
if (mdlen < 0)
return 0;
hctx_tpl = HMAC_CTX_new();
if (hctx_tpl == NULL)
return 0;
p = key;
tkeylen = keylen;
if (!HMAC_Init_ex(hctx_tpl, pass, passlen, digest, NULL))
goto err;
hctx = HMAC_CTX_new();
if (hctx == NULL)
goto err;
while (tkeylen) {
if (tkeylen > mdlen)
cplen = mdlen;
else
cplen = tkeylen;
/*
* We are unlikely to ever use more than 256 blocks (5120 bits!) but
* just in case...
*/
itmp[0] = (unsigned char)((i >> 24) & 0xff);
itmp[1] = (unsigned char)((i >> 16) & 0xff);
itmp[2] = (unsigned char)((i >> 8) & 0xff);
itmp[3] = (unsigned char)(i & 0xff);
if (!HMAC_CTX_copy(hctx, hctx_tpl))
goto err;
if (!HMAC_Update(hctx, salt, saltlen)
|| !HMAC_Update(hctx, itmp, 4)
|| !HMAC_Final(hctx, digtmp, NULL))
goto err;
memcpy(p, digtmp, cplen);
for (j = 1; j < iter; j++) {
if (!HMAC_CTX_copy(hctx, hctx_tpl))
goto err;
if (!HMAC_Update(hctx, digtmp, mdlen)
|| !HMAC_Final(hctx, digtmp, NULL))
goto err;
for (k = 0; k < cplen; k++)
p[k] ^= digtmp[k];
}
tkeylen -= cplen;
i++;
p += cplen;
}
ret = 1;
err:
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return ret;
}