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/*
* Copyright 1999-2016 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
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include <stdlib.h>
#include "internal/cryptlib.h"
# include <openssl/x509.h>
# include <openssl/evp.h>
# include <openssl/hmac.h>
# include "evp_locl.h"
/* set this to print out info about the keygen algorithm */
/* #define OPENSSL_DEBUG_PKCS5V2 */
# ifdef OPENSSL_DEBUG_PKCS5V2
static void h__dump(const unsigned char *p, int len);
# endif
/*
* 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.
*/
int PKCS5_PBKDF2_HMAC(const char *pass, int passlen,
const unsigned char *salt, int saltlen, int iter,
const EVP_MD *digest, int keylen, unsigned char *out)
{
const char *empty = "";
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 = out;
tkeylen = keylen;
if (pass == NULL) {
pass = empty;
passlen = 0;
} else if (passlen == -1) {
passlen = strlen(pass);
}
if (!HMAC_Init_ex(hctx_tpl, pass, passlen, digest, NULL)) {
HMAC_CTX_free(hctx_tpl);
return 0;
}
hctx = HMAC_CTX_new();
if (hctx == NULL) {
HMAC_CTX_free(hctx_tpl);
return 0;
}
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)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
if (!HMAC_Update(hctx, salt, saltlen)
|| !HMAC_Update(hctx, itmp, 4)
|| !HMAC_Final(hctx, digtmp, NULL)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
memcpy(p, digtmp, cplen);
for (j = 1; j < iter; j++) {
if (!HMAC_CTX_copy(hctx, hctx_tpl)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
if (!HMAC_Update(hctx, digtmp, mdlen)
|| !HMAC_Final(hctx, digtmp, NULL)) {
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
return 0;
}
for (k = 0; k < cplen; k++)
p[k] ^= digtmp[k];
}
tkeylen -= cplen;
i++;
p += cplen;
}
HMAC_CTX_free(hctx);
HMAC_CTX_free(hctx_tpl);
# ifdef OPENSSL_DEBUG_PKCS5V2
fprintf(stderr, "Password:\n");
h__dump(pass, passlen);
fprintf(stderr, "Salt:\n");
h__dump(salt, saltlen);
fprintf(stderr, "Iteration count %d\n", iter);
fprintf(stderr, "Key:\n");
h__dump(out, keylen);
# endif
return 1;
}
int PKCS5_PBKDF2_HMAC_SHA1(const char *pass, int passlen,
const unsigned char *salt, int saltlen, int iter,
int keylen, unsigned char *out)
{
return PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, EVP_sha1(),
keylen, out);
}
/*
* Now the key derivation function itself. This is a bit evil because it has
* to check the ASN1 parameters are valid: and there are quite a few of
* them...
*/
int PKCS5_v2_PBE_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass, int passlen,
ASN1_TYPE *param, const EVP_CIPHER *c,
const EVP_MD *md, int en_de)
{
PBE2PARAM *pbe2 = NULL;
const EVP_CIPHER *cipher;
EVP_PBE_KEYGEN *kdf;
int rv = 0;
pbe2 = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(PBE2PARAM), param);
if (pbe2 == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_DECODE_ERROR);
goto err;
}
/* See if we recognise the key derivation function */
if (!EVP_PBE_find(EVP_PBE_TYPE_KDF, OBJ_obj2nid(pbe2->keyfunc->algorithm),
NULL, NULL, &kdf)) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN,
EVP_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);
goto err;
}
/*
* lets see if we recognise the encryption algorithm.
*/
cipher = EVP_get_cipherbyobj(pbe2->encryption->algorithm);
if (!cipher) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_UNSUPPORTED_CIPHER);
goto err;
}
/* Fixup cipher based on AlgorithmIdentifier */
if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, en_de))
goto err;
if (EVP_CIPHER_asn1_to_param(ctx, pbe2->encryption->parameter) < 0) {
EVPerr(EVP_F_PKCS5_V2_PBE_KEYIVGEN, EVP_R_CIPHER_PARAMETER_ERROR);
goto err;
}
rv = kdf(ctx, pass, passlen, pbe2->keyfunc->parameter, NULL, NULL, en_de);
err:
PBE2PARAM_free(pbe2);
return rv;
}
int PKCS5_v2_PBKDF2_keyivgen(EVP_CIPHER_CTX *ctx, const char *pass,
int passlen, ASN1_TYPE *param,
const EVP_CIPHER *c, const EVP_MD *md, int en_de)
{
unsigned char *salt, key[EVP_MAX_KEY_LENGTH];
int saltlen, iter;
int rv = 0;
unsigned int keylen = 0;
int prf_nid, hmac_md_nid;
PBKDF2PARAM *kdf = NULL;
const EVP_MD *prfmd;
if (EVP_CIPHER_CTX_cipher(ctx) == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_NO_CIPHER_SET);
goto err;
}
keylen = EVP_CIPHER_CTX_key_length(ctx);
OPENSSL_assert(keylen <= sizeof(key));
/* Decode parameter */
kdf = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(PBKDF2PARAM), param);
if (kdf == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_DECODE_ERROR);
goto err;
}
keylen = EVP_CIPHER_CTX_key_length(ctx);
/* Now check the parameters of the kdf */
if (kdf->keylength && (ASN1_INTEGER_get(kdf->keylength) != (int)keylen)) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_KEYLENGTH);
goto err;
}
if (kdf->prf)
prf_nid = OBJ_obj2nid(kdf->prf->algorithm);
else
prf_nid = NID_hmacWithSHA1;
if (!EVP_PBE_find(EVP_PBE_TYPE_PRF, prf_nid, NULL, &hmac_md_nid, 0)) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
goto err;
}
prfmd = EVP_get_digestbynid(hmac_md_nid);
if (prfmd == NULL) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_PRF);
goto err;
}
if (kdf->salt->type != V_ASN1_OCTET_STRING) {
EVPerr(EVP_F_PKCS5_V2_PBKDF2_KEYIVGEN, EVP_R_UNSUPPORTED_SALT_TYPE);
goto err;
}
/* it seems that its all OK */
salt = kdf->salt->value.octet_string->data;
saltlen = kdf->salt->value.octet_string->length;
iter = ASN1_INTEGER_get(kdf->iter);
if (!PKCS5_PBKDF2_HMAC(pass, passlen, salt, saltlen, iter, prfmd,
keylen, key))
goto err;
rv = EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de);
err:
OPENSSL_cleanse(key, keylen);
PBKDF2PARAM_free(kdf);
return rv;
}
# ifdef OPENSSL_DEBUG_PKCS5V2
static void h__dump(const unsigned char *p, int len)
{
for (; len--; p++)
fprintf(stderr, "%02X ", *p);
fprintf(stderr, "\n");
}
# endif
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