diff options
author | Dr. Stephen Henson <steve@openssl.org> | 2015-05-20 13:23:06 +0100 |
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committer | Dr. Stephen Henson <steve@openssl.org> | 2015-05-21 12:48:02 +0100 |
commit | e98aa30d555cb5a656d320a0f86ab5b3b1dce2db (patch) | |
tree | 5ea26c5e2258ee325abd0757ea253d82dedaa91c /crypto/asn1/p5_scrypt.c | |
parent | 96b96d6c456befe49d5845a029e2bb0a4addc58d (diff) |
Add scrypt PBE algorithm code.
This adds support for the ASN.1 structures in draft-josefsson-scrypt-kdf-03
Private keys encrypted by scrypt can now be decrypted transparently as long
as they don't exceed the memory limits.
Reviewed-by: Rich Salz <rsalz@openssl.org>
Diffstat (limited to 'crypto/asn1/p5_scrypt.c')
-rw-r--r-- | crypto/asn1/p5_scrypt.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/crypto/asn1/p5_scrypt.c b/crypto/asn1/p5_scrypt.c new file mode 100644 index 0000000000..5c4de797f9 --- /dev/null +++ b/crypto/asn1/p5_scrypt.c @@ -0,0 +1,332 @@ +/* p5_scrypt.c */ +/* + * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project + * 2015. + */ +/* ==================================================================== + * Copyright (c) 2015 The OpenSSL Project. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * 3. All advertising materials mentioning features or use of this + * software must display the following acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" + * + * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to + * endorse or promote products derived from this software without + * prior written permission. For written permission, please contact + * licensing@OpenSSL.org. + * + * 5. Products derived from this software may not be called "OpenSSL" + * nor may "OpenSSL" appear in their names without prior written + * permission of the OpenSSL Project. + * + * 6. Redistributions of any form whatsoever must retain the following + * acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" + * + * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY + * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR + * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + * ==================================================================== + * + * This product includes cryptographic software written by Eric Young + * (eay@cryptsoft.com). This product includes software written by Tim + * Hudson (tjh@cryptsoft.com). + * + */ + +#include <stdio.h> +#include "internal/cryptlib.h" +#include <openssl/asn1t.h> +#include <openssl/err.h> +#include <openssl/evp.h> +#include <openssl/x509.h> +#include <openssl/rand.h> + +/* PKCS#5 scrypt password based encryption structures */ + +typedef struct { + ASN1_OCTET_STRING *salt; + ASN1_INTEGER *costParameter; + ASN1_INTEGER *blockSize; + ASN1_INTEGER *parallelizationParameter; + ASN1_INTEGER *keyLength; +} SCRYPT_PARAMS; + +ASN1_SEQUENCE(SCRYPT_PARAMS) = { + ASN1_SIMPLE(SCRYPT_PARAMS, salt, ASN1_OCTET_STRING), + ASN1_SIMPLE(SCRYPT_PARAMS, costParameter, ASN1_INTEGER), + ASN1_SIMPLE(SCRYPT_PARAMS, blockSize, ASN1_INTEGER), + ASN1_SIMPLE(SCRYPT_PARAMS, parallelizationParameter, ASN1_INTEGER), + ASN1_OPT(SCRYPT_PARAMS, keyLength, ASN1_INTEGER), +} ASN1_SEQUENCE_END(SCRYPT_PARAMS) + +DECLARE_ASN1_ALLOC_FUNCTIONS(SCRYPT_PARAMS) +IMPLEMENT_ASN1_ALLOC_FUNCTIONS(SCRYPT_PARAMS) + +static X509_ALGOR *pkcs5_scrypt_set(const unsigned char *salt, size_t saltlen, + size_t keylen, uint64_t N, uint64_t r, + uint64_t p); + +/* + * Return an algorithm identifier for a PKCS#5 v2.0 PBE algorithm using scrypt + */ + +X509_ALGOR *PKCS5_pbe2_set_scrypt(const EVP_CIPHER *cipher, + const unsigned char *salt, int saltlen, + unsigned char *aiv, uint64_t N, uint64_t r, + uint64_t p) +{ + X509_ALGOR *scheme = NULL, *kalg = NULL, *ret = NULL; + int alg_nid; + size_t keylen = 0; + EVP_CIPHER_CTX ctx; + unsigned char iv[EVP_MAX_IV_LENGTH]; + PBE2PARAM *pbe2 = NULL; + ASN1_OBJECT *obj; + + if (!cipher) { + ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT, ERR_R_PASSED_NULL_PARAMETER); + goto err; + } + + if (EVP_PBE_scrypt(NULL, 0, NULL, 0, N, r, p, 0, NULL, 0) == 0) { + ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT, + ASN1_R_INVALID_SCRYPT_PARAMETERS); + goto err; + } + + alg_nid = EVP_CIPHER_type(cipher); + if (alg_nid == NID_undef) { + ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT, + ASN1_R_CIPHER_HAS_NO_OBJECT_IDENTIFIER); + goto err; + } + obj = OBJ_nid2obj(alg_nid); + pbe2 = PBE2PARAM_new(); + if (pbe2 == NULL) + goto merr; + + /* Setup the AlgorithmIdentifier for the encryption scheme */ + scheme = pbe2->encryption; + + scheme->algorithm = obj; + scheme->parameter = ASN1_TYPE_new(); + if (scheme->parameter == NULL) + goto merr; + + /* Create random IV */ + if (EVP_CIPHER_iv_length(cipher)) { + if (aiv) + memcpy(iv, aiv, EVP_CIPHER_iv_length(cipher)); + else if (RAND_bytes(iv, EVP_CIPHER_iv_length(cipher)) < 0) + goto err; + } + + EVP_CIPHER_CTX_init(&ctx); + + /* Dummy cipherinit to just setup the IV */ + if (EVP_CipherInit_ex(&ctx, cipher, NULL, NULL, iv, 0) == 0) + goto err; + if (EVP_CIPHER_param_to_asn1(&ctx, scheme->parameter) < 0) { + ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT, + ASN1_R_ERROR_SETTING_CIPHER_PARAMS); + EVP_CIPHER_CTX_cleanup(&ctx); + goto err; + } + EVP_CIPHER_CTX_cleanup(&ctx); + + /* If its RC2 then we'd better setup the key length */ + + if (alg_nid == NID_rc2_cbc) + keylen = EVP_CIPHER_key_length(cipher); + + /* Setup keyfunc */ + + X509_ALGOR_free(pbe2->keyfunc); + + pbe2->keyfunc = pkcs5_scrypt_set(salt, saltlen, keylen, N, r, p); + + if (pbe2->keyfunc == NULL) + goto merr; + + /* Now set up top level AlgorithmIdentifier */ + + ret = X509_ALGOR_new(); + if (ret == NULL) + goto merr; + + ret->algorithm = OBJ_nid2obj(NID_pbes2); + + /* Encode PBE2PARAM into parameter */ + + if (ASN1_TYPE_pack_sequence(ASN1_ITEM_rptr(PBE2PARAM), pbe2, + &ret->parameter) == NULL) + goto merr; + + PBE2PARAM_free(pbe2); + pbe2 = NULL; + + return ret; + + merr: + ASN1err(ASN1_F_PKCS5_PBE2_SET_SCRYPT, ERR_R_MALLOC_FAILURE); + + err: + PBE2PARAM_free(pbe2); + X509_ALGOR_free(kalg); + X509_ALGOR_free(ret); + + return NULL; + +} + +static X509_ALGOR *pkcs5_scrypt_set(const unsigned char *salt, size_t saltlen, + size_t keylen, uint64_t N, uint64_t r, + uint64_t p) +{ + X509_ALGOR *keyfunc = NULL; + SCRYPT_PARAMS *sparam = NULL; + + sparam = SCRYPT_PARAMS_new(); + if (sparam == NULL) + goto merr; + + if (!saltlen) + saltlen = PKCS5_SALT_LEN; + + /* This will either copy salt or grow the buffer */ + if (ASN1_STRING_set(sparam->salt, salt, saltlen) == 0) + goto merr; + + if (salt == NULL && RAND_bytes(sparam->salt->data, saltlen) <= 0) + goto err; + + if (ASN1_INTEGER_set_uint64(sparam->costParameter, N) == 0) + goto merr; + + if (ASN1_INTEGER_set_uint64(sparam->blockSize, r) == 0) + goto merr; + + if (ASN1_INTEGER_set_uint64(sparam->parallelizationParameter, p) == 0) + goto merr; + + /* If have a key len set it up */ + + if (keylen > 0) { + sparam->keyLength = ASN1_INTEGER_new(); + if (sparam->keyLength == NULL) + goto merr; + if (ASN1_INTEGER_set_int64(sparam->keyLength, keylen) == 0) + goto merr; + } + + /* Finally setup the keyfunc structure */ + + keyfunc = X509_ALGOR_new(); + if (!keyfunc) + goto merr; + + keyfunc->algorithm = OBJ_nid2obj(NID_id_scrypt); + + /* Encode SCRYPT_PARAMS into parameter of pbe2 */ + + if (ASN1_TYPE_pack_sequence(ASN1_ITEM_rptr(SCRYPT_PARAMS), sparam, + &keyfunc->parameter) == NULL) + goto merr; + + SCRYPT_PARAMS_free(sparam); + return keyfunc; + + merr: + ASN1err(ASN1_F_PKCS5_SCRYPT_SET, ERR_R_MALLOC_FAILURE); + err: + SCRYPT_PARAMS_free(sparam); + X509_ALGOR_free(keyfunc); + return NULL; +} + +int PKCS5_v2_scrypt_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]; + uint64_t p, r, N; + size_t saltlen; + size_t keylen = 0; + int rv = 0; + SCRYPT_PARAMS *sparam = NULL; + + if (EVP_CIPHER_CTX_cipher(ctx) == NULL) { + EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN, EVP_R_NO_CIPHER_SET); + goto err; + } + + /* Decode parameter */ + + sparam = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(SCRYPT_PARAMS), param); + + if (sparam == NULL) { + EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN, EVP_R_DECODE_ERROR); + goto err; + } + + keylen = EVP_CIPHER_CTX_key_length(ctx); + + /* Now check the parameters of sparam */ + + if (sparam->keyLength) { + uint64_t spkeylen; + if ((ASN1_INTEGER_get_uint64(&spkeylen, sparam->keyLength) == 0) + || (spkeylen != keylen)) { + EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN, + EVP_R_UNSUPPORTED_KEYLENGTH); + goto err; + } + } + /* Check all parameters fit in uint64_t and are acceptable to scrypt */ + if (ASN1_INTEGER_get_uint64(&N, sparam->costParameter) == 0 + || ASN1_INTEGER_get_uint64(&r, sparam->blockSize) == 0 + || ASN1_INTEGER_get_uint64(&p, sparam->parallelizationParameter) == 0 + || EVP_PBE_scrypt(NULL, 0, NULL, 0, N, r, p, 0, NULL, 0) == 0) { + EVPerr(EVP_F_PKCS5_V2_SCRYPT_KEYIVGEN, + EVP_R_ILLEGAL_SCRYPT_PARAMETERS); + goto err; + } + + /* it seems that its all OK */ + + salt = sparam->salt->data; + saltlen = sparam->salt->length; + if (EVP_PBE_scrypt(pass, passlen, salt, saltlen, N, r, p, 0, key, keylen) + == 0) + goto err; + rv = EVP_CipherInit_ex(ctx, NULL, NULL, key, NULL, en_de); + err: + if (keylen) + OPENSSL_cleanse(key, keylen); + SCRYPT_PARAMS_free(sparam); + return rv; +} |