/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
* project 1999.
*/
/* ====================================================================
* Copyright (c) 1999 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 <openssl_grpc/pkcs8.h>
#include <assert.h>
#include <limits.h>
#include <string.h>
#include <openssl_grpc/bytestring.h>
#include <openssl_grpc/cipher.h>
#include <openssl_grpc/digest.h>
#include <openssl_grpc/err.h>
#include <openssl_grpc/mem.h>
#include <openssl_grpc/nid.h>
#include <openssl_grpc/rand.h>
#include "internal.h"
#include "../bytestring/internal.h"
#include "../internal.h"
static int pkcs12_encode_password(const char *in, size_t in_len, uint8_t **out,
size_t *out_len) {
CBB cbb;
if (!CBB_init(&cbb, in_len * 2)) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
return 0;
}
// Convert the password to BMPString, or UCS-2. See
// https://tools.ietf.org/html/rfc7292#appendix-B.1.
CBS cbs;
CBS_init(&cbs, (const uint8_t *)in, in_len);
while (CBS_len(&cbs) != 0) {
uint32_t c;
if (!cbs_get_utf8(&cbs, &c) ||
!cbb_add_ucs2_be(&cbb, c)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_INVALID_CHARACTERS);
goto err;
}
}
// Terminate the result with a UCS-2 NUL.
if (!cbb_add_ucs2_be(&cbb, 0) ||
!CBB_finish(&cbb, out, out_len)) {
goto err;
}
return 1;
err:
CBB_cleanup(&cbb);
return 0;
}
int pkcs12_key_gen(const char *pass, size_t pass_len, const uint8_t *salt,
size_t salt_len, uint8_t id, unsigned iterations,
size_t out_len, uint8_t *out, const EVP_MD *md) {
// See https://tools.ietf.org/html/rfc7292#appendix-B. Quoted parts of the
// specification have errata applied and other typos fixed.
if (iterations < 1) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_ITERATION_COUNT);
return 0;
}
int ret = 0;
EVP_MD_CTX ctx;
EVP_MD_CTX_init(&ctx);
uint8_t *pass_raw = NULL, *I = NULL;
size_t pass_raw_len = 0, I_len = 0;
// If |pass| is NULL, we use the empty string rather than {0, 0} as the raw
// password.
if (pass != NULL &&
!pkcs12_encode_password(pass, pass_len, &pass_raw, &pass_raw_len)) {
goto err;
}
// In the spec, |block_size| is called "v", but measured in bits.
size_t block_size = EVP_MD_block_size(md);
// 1. Construct a string, D (the "diversifier"), by concatenating v/8 copies
// of ID.
uint8_t D[EVP_MAX_MD_BLOCK_SIZE];
OPENSSL_memset(D, id, block_size);
// 2. Concatenate copies of the salt together to create a string S of length
// v(ceiling(s/v)) bits (the final copy of the salt may be truncated to
// create S). Note that if the salt is the empty string, then so is S.
//
// 3. Concatenate copies of the password together to create a string P of
// length v(ceiling(p/v)) bits (the final copy of the password may be
// truncated to create P). Note that if the password is the empty string,
// then so is P.
//
// 4. Set I=S||P to be the concatenation of S and P.
if (salt_len + block_size - 1 < salt_len ||
pass_raw_len + block_size - 1 < pass_raw_len) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
goto err;
}
size_t S_len = block_size * ((salt_len + block_size - 1) / block_size);
size_t P_len = block_size * ((pass_raw_len + block_size - 1) / block_size);
I_len = S_len + P_len;
if (I_len < S_len) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
goto err;
}
I = OPENSSL_malloc(I_len);
if (I_len != 0 && I == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
goto err;
}
for (size_t i = 0; i < S_len; i++) {
I[i] = salt[i % salt_len];
}
for (size_t i = 0; i < P_len; i++) {
I[i + S_len] = pass_raw[i % pass_raw_len];
}
while (out_len != 0) {
// A. Set A_i=H^r(D||I). (i.e., the r-th hash of D||I,
// H(H(H(... H(D||I))))
uint8_t A[EVP_MAX_MD_SIZE];
unsigned A_len;
if (!EVP_DigestInit_ex(&ctx, md, NULL) ||
!EVP_DigestUpdate(&ctx, D, block_size) ||
!EVP_DigestUpdate(&ctx, I, I_len) ||
!EVP_DigestFinal_ex(&ctx, A, &A_len)) {
goto err;
}
for (unsigned iter = 1; iter < iterations; iter++) {
if (!EVP_DigestInit_ex(&ctx, md, NULL) ||
!EVP_DigestUpdate(&ctx, A, A_len) ||
!EVP_DigestFinal_ex(&ctx, A, &A_len)) {
goto err;
}
}
size_t todo = out_len < A_len ? out_len : A_len;
OPENSSL_memcpy(out, A, todo);
out += todo;
out_len -= todo;
if (out_len == 0) {
break;
}
// B. Concatenate copies of A_i to create a string B of length v bits (the
// final copy of A_i may be truncated to create B).
uint8_t B[EVP_MAX_MD_BLOCK_SIZE];
for (size_t i = 0; i < block_size; i++) {
B[i] = A[i % A_len];
}
// C. Treating I as a concatenation I_0, I_1, ..., I_(k-1) of v-bit blocks,
// where k=ceiling(s/v)+ceiling(p/v), modify I by setting I_j=(I_j+B+1) mod
// 2^v for each j.
assert(I_len % block_size == 0);
for (size_t i = 0; i < I_len; i += block_size) {
unsigned carry = 1;
for (size_t j = block_size - 1; j < block_size; j--) {
carry += I[i + j] + B[j];
I[i + j] = (uint8_t)carry;
carry >>= 8;
}
}
}
ret = 1;
err:
OPENSSL_free(I);
OPENSSL_free(pass_raw);
EVP_MD_CTX_cleanup(&ctx);
return ret;
}
static int pkcs12_pbe_cipher_init(const struct pbe_suite *suite,
EVP_CIPHER_CTX *ctx, unsigned iterations,
const char *pass, size_t pass_len,
const uint8_t *salt, size_t salt_len,
int is_encrypt) {
const EVP_CIPHER *cipher = suite->cipher_func();
const EVP_MD *md = suite->md_func();
uint8_t key[EVP_MAX_KEY_LENGTH];
uint8_t iv[EVP_MAX_IV_LENGTH];
if (!pkcs12_key_gen(pass, pass_len, salt, salt_len, PKCS12_KEY_ID, iterations,
EVP_CIPHER_key_length(cipher), key, md) ||
!pkcs12_key_gen(pass, pass_len, salt, salt_len, PKCS12_IV_ID, iterations,
EVP_CIPHER_iv_length(cipher), iv, md)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_KEY_GEN_ERROR);
return 0;
}
int ret = EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, is_encrypt);
OPENSSL_cleanse(key, EVP_MAX_KEY_LENGTH);
OPENSSL_cleanse(iv, EVP_MAX_IV_LENGTH);
return ret;
}
static int pkcs12_pbe_decrypt_init(const struct pbe_suite *suite,
EVP_CIPHER_CTX *ctx, const char *pass,
size_t pass_len, CBS *param) {
CBS pbe_param, salt;
uint64_t iterations;
if (!CBS_get_asn1(param, &pbe_param, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&pbe_param, &salt, CBS_ASN1_OCTETSTRING) ||
!CBS_get_asn1_uint64(&pbe_param, &iterations) ||
CBS_len(&pbe_param) != 0 ||
CBS_len(param) != 0) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
return 0;
}
if (!pkcs12_iterations_acceptable(iterations)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_ITERATION_COUNT);
return 0;
}
return pkcs12_pbe_cipher_init(suite, ctx, (unsigned)iterations, pass,
pass_len, CBS_data(&salt), CBS_len(&salt),
0 /* decrypt */);
}
static const struct pbe_suite kBuiltinPBE[] = {
{
NID_pbe_WithSHA1And40BitRC2_CBC,
// 1.2.840.113549.1.12.1.6
{0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x0c, 0x01, 0x06},
10,
EVP_rc2_40_cbc,
EVP_sha1,
pkcs12_pbe_decrypt_init,
},
{
NID_pbe_WithSHA1And128BitRC4,
// 1.2.840.113549.1.12.1.1
{0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x0c, 0x01, 0x01},
10,
EVP_rc4,
EVP_sha1,
pkcs12_pbe_decrypt_init,
},
{
NID_pbe_WithSHA1And3_Key_TripleDES_CBC,
// 1.2.840.113549.1.12.1.3
{0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x0c, 0x01, 0x03},
10,
EVP_des_ede3_cbc,
EVP_sha1,
pkcs12_pbe_decrypt_init,
},
{
NID_pbes2,
// 1.2.840.113549.1.5.13
{0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x05, 0x0d},
9,
NULL,
NULL,
PKCS5_pbe2_decrypt_init,
},
};
static const struct pbe_suite *get_pkcs12_pbe_suite(int pbe_nid) {
for (unsigned i = 0; i < OPENSSL_ARRAY_SIZE(kBuiltinPBE); i++) {
if (kBuiltinPBE[i].pbe_nid == pbe_nid &&
// If |cipher_func| or |md_func| are missing, this is a PBES2 scheme.
kBuiltinPBE[i].cipher_func != NULL &&
kBuiltinPBE[i].md_func != NULL) {
return &kBuiltinPBE[i];
}
}
return NULL;
}
int pkcs12_pbe_encrypt_init(CBB *out, EVP_CIPHER_CTX *ctx, int alg,
unsigned iterations, const char *pass,
size_t pass_len, const uint8_t *salt,
size_t salt_len) {
const struct pbe_suite *suite = get_pkcs12_pbe_suite(alg);
if (suite == NULL) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_ALGORITHM);
return 0;
}
// See RFC 2898, appendix A.3.
CBB algorithm, oid, param, salt_cbb;
if (!CBB_add_asn1(out, &algorithm, CBS_ASN1_SEQUENCE) ||
!CBB_add_asn1(&algorithm, &oid, CBS_ASN1_OBJECT) ||
!CBB_add_bytes(&oid, suite->oid, suite->oid_len) ||
!CBB_add_asn1(&algorithm, ¶m, CBS_ASN1_SEQUENCE) ||
!CBB_add_asn1(¶m, &salt_cbb, CBS_ASN1_OCTETSTRING) ||
!CBB_add_bytes(&salt_cbb, salt, salt_len) ||
!CBB_add_asn1_uint64(¶m, iterations) ||
!CBB_flush(out)) {
return 0;
}
return pkcs12_pbe_cipher_init(suite, ctx, iterations, pass, pass_len, salt,
salt_len, 1 /* encrypt */);
}
int pkcs8_pbe_decrypt(uint8_t **out, size_t *out_len, CBS *algorithm,
const char *pass, size_t pass_len, const uint8_t *in,
size_t in_len) {
int ret = 0;
uint8_t *buf = NULL;;
EVP_CIPHER_CTX ctx;
EVP_CIPHER_CTX_init(&ctx);
CBS obj;
if (!CBS_get_asn1(algorithm, &obj, CBS_ASN1_OBJECT)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
goto err;
}
const struct pbe_suite *suite = NULL;
for (unsigned i = 0; i < OPENSSL_ARRAY_SIZE(kBuiltinPBE); i++) {
if (CBS_mem_equal(&obj, kBuiltinPBE[i].oid, kBuiltinPBE[i].oid_len)) {
suite = &kBuiltinPBE[i];
break;
}
}
if (suite == NULL) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_ALGORITHM);
goto err;
}
if (!suite->decrypt_init(suite, &ctx, pass, pass_len, algorithm)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_KEYGEN_FAILURE);
goto err;
}
buf = OPENSSL_malloc(in_len);
if (buf == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
goto err;
}
if (in_len > INT_MAX) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
goto err;
}
int n1, n2;
if (!EVP_DecryptUpdate(&ctx, buf, &n1, in, (int)in_len) ||
!EVP_DecryptFinal_ex(&ctx, buf + n1, &n2)) {
goto err;
}
*out = buf;
*out_len = n1 + n2;
ret = 1;
buf = NULL;
err:
OPENSSL_free(buf);
EVP_CIPHER_CTX_cleanup(&ctx);
return ret;
}
EVP_PKEY *PKCS8_parse_encrypted_private_key(CBS *cbs, const char *pass,
size_t pass_len) {
// See RFC 5208, section 6.
CBS epki, algorithm, ciphertext;
if (!CBS_get_asn1(cbs, &epki, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&epki, &algorithm, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&epki, &ciphertext, CBS_ASN1_OCTETSTRING) ||
CBS_len(&epki) != 0) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
return 0;
}
uint8_t *out;
size_t out_len;
if (!pkcs8_pbe_decrypt(&out, &out_len, &algorithm, pass, pass_len,
CBS_data(&ciphertext), CBS_len(&ciphertext))) {
return 0;
}
CBS pki;
CBS_init(&pki, out, out_len);
EVP_PKEY *ret = EVP_parse_private_key(&pki);
OPENSSL_free(out);
return ret;
}
int PKCS8_marshal_encrypted_private_key(CBB *out, int pbe_nid,
const EVP_CIPHER *cipher,
const char *pass, size_t pass_len,
const uint8_t *salt, size_t salt_len,
int iterations, const EVP_PKEY *pkey) {
int ret = 0;
uint8_t *plaintext = NULL, *salt_buf = NULL;
size_t plaintext_len = 0;
EVP_CIPHER_CTX ctx;
EVP_CIPHER_CTX_init(&ctx);
// Generate a random salt if necessary.
if (salt == NULL) {
if (salt_len == 0) {
salt_len = PKCS5_SALT_LEN;
}
salt_buf = OPENSSL_malloc(salt_len);
if (salt_buf == NULL ||
!RAND_bytes(salt_buf, salt_len)) {
goto err;
}
salt = salt_buf;
}
if (iterations <= 0) {
iterations = PKCS12_DEFAULT_ITER;
}
// Serialize the input key.
CBB plaintext_cbb;
if (!CBB_init(&plaintext_cbb, 128) ||
!EVP_marshal_private_key(&plaintext_cbb, pkey) ||
!CBB_finish(&plaintext_cbb, &plaintext, &plaintext_len)) {
CBB_cleanup(&plaintext_cbb);
goto err;
}
CBB epki;
if (!CBB_add_asn1(out, &epki, CBS_ASN1_SEQUENCE)) {
goto err;
}
// TODO(davidben): OpenSSL has since extended |pbe_nid| to control either the
// PBES1 scheme or the PBES2 PRF. E.g. passing |NID_hmacWithSHA256| will
// select PBES2 with HMAC-SHA256 as the PRF. Implement this if anything uses
// it. See 5693a30813a031d3921a016a870420e7eb93ec90 in OpenSSL.
int alg_ok;
if (pbe_nid == -1) {
alg_ok = PKCS5_pbe2_encrypt_init(&epki, &ctx, cipher, (unsigned)iterations,
pass, pass_len, salt, salt_len);
} else {
alg_ok = pkcs12_pbe_encrypt_init(&epki, &ctx, pbe_nid, (unsigned)iterations,
pass, pass_len, salt, salt_len);
}
if (!alg_ok) {
goto err;
}
size_t max_out = plaintext_len + EVP_CIPHER_CTX_block_size(&ctx);
if (max_out < plaintext_len) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_TOO_LONG);
goto err;
}
CBB ciphertext;
uint8_t *ptr;
int n1, n2;
if (!CBB_add_asn1(&epki, &ciphertext, CBS_ASN1_OCTETSTRING) ||
!CBB_reserve(&ciphertext, &ptr, max_out) ||
!EVP_CipherUpdate(&ctx, ptr, &n1, plaintext, plaintext_len) ||
!EVP_CipherFinal_ex(&ctx, ptr + n1, &n2) ||
!CBB_did_write(&ciphertext, n1 + n2) ||
!CBB_flush(out)) {
goto err;
}
ret = 1;
err:
OPENSSL_free(plaintext);
OPENSSL_free(salt_buf);
EVP_CIPHER_CTX_cleanup(&ctx);
return ret;
}