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boringssl/crypto/pkcs8/pkcs8.c
David Benjamin 582d2847ed Reimplement PKCS#12 key derivation. 
This is avoids pulling in BIGNUM for doing a straight-forward addition on a
block-sized value, and avoids a ton of mallocs. It's also -Wconversion-clean,
unlike the old one.

In doing so, this replaces the HMAC_MAX_MD_CBLOCK with EVP_MAX_MD_BLOCK_SIZE.
By having the maximum block size available, most of the temporary values in the
key derivation don't need to be malloc'd.

BUG=22

Change-Id: I940a62bba4ea32bf82b1190098f3bf185d4cc7fe
Reviewed-on: https://boringssl-review.googlesource.com/7688
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
2016-04-19 18:16:38 +00:00

1222 lines
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/* 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/pkcs8.h>
#include <assert.h>
#include <limits.h>
#include <string.h>
#include <openssl/asn1.h>
#include <openssl/buf.h>
#include <openssl/bytestring.h>
#include <openssl/cipher.h>
#include <openssl/digest.h>
#include <openssl/err.h>
#include <openssl/hmac.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/x509.h>
#include "internal.h"
#include "../bytestring/internal.h"
#define PKCS12_KEY_ID 1
#define PKCS12_IV_ID 2
#define PKCS12_MAC_ID 3
static int ascii_to_ucs2(const char *ascii, size_t ascii_len,
uint8_t **out, size_t *out_len) {
uint8_t *unitmp;
size_t ulen, i;
ulen = ascii_len * 2 + 2;
if (ulen < ascii_len) {
return 0;
}
unitmp = OPENSSL_malloc(ulen);
if (unitmp == NULL) {
return 0;
}
for (i = 0; i < ulen - 2; i += 2) {
unitmp[i] = 0;
unitmp[i + 1] = ascii[i >> 1];
}
/* Make result double null terminated */
unitmp[ulen - 2] = 0;
unitmp[ulen - 1] = 0;
*out_len = ulen;
*out = unitmp;
return 1;
}
static int pkcs12_key_gen_raw(const uint8_t *pass_raw, size_t pass_raw_len,
const uint8_t *salt, size_t salt_len,
uint8_t id, int 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;
}
/* 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];
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);
return 0;
}
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);
size_t I_len = S_len + P_len;
if (I_len < S_len) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
return 0;
}
uint8_t *I = OPENSSL_malloc(I_len);
if (I_len != 0 && I == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
return 0;
}
size_t i;
for (i = 0; i < S_len; i++) {
I[i] = salt[i % salt_len];
}
for (i = 0; i < P_len; i++) {
I[i + S_len] = pass_raw[i % pass_raw_len];
}
int ret = 0;
EVP_MD_CTX ctx;
EVP_MD_CTX_init(&ctx);
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;
}
int iter;
for (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;
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 (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 (i = 0; i < I_len; i += block_size) {
unsigned carry = 1;
size_t j;
for (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_cleanse(I, I_len);
OPENSSL_free(I);
EVP_MD_CTX_cleanup(&ctx);
return ret;
}
static int pkcs12_pbe_keyivgen(EVP_CIPHER_CTX *ctx, const uint8_t *pass_raw,
size_t pass_raw_len, ASN1_TYPE *param,
const EVP_CIPHER *cipher, const EVP_MD *md,
int is_encrypt) {
PBEPARAM *pbe;
int salt_len, iterations, ret;
uint8_t *salt;
const uint8_t *pbuf;
uint8_t key[EVP_MAX_KEY_LENGTH], iv[EVP_MAX_IV_LENGTH];
/* Extract useful info from parameter */
if (param == NULL || param->type != V_ASN1_SEQUENCE ||
param->value.sequence == NULL) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
return 0;
}
pbuf = param->value.sequence->data;
pbe = d2i_PBEPARAM(NULL, &pbuf, param->value.sequence->length);
if (pbe == NULL) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
return 0;
}
if (!pbe->iter) {
iterations = 1;
} else {
iterations = ASN1_INTEGER_get(pbe->iter);
}
salt = pbe->salt->data;
salt_len = pbe->salt->length;
if (!pkcs12_key_gen_raw(pass_raw, pass_raw_len, salt, salt_len, PKCS12_KEY_ID,
iterations, EVP_CIPHER_key_length(cipher), key, md)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_KEY_GEN_ERROR);
PBEPARAM_free(pbe);
return 0;
}
if (!pkcs12_key_gen_raw(pass_raw, pass_raw_len, salt, salt_len, PKCS12_IV_ID,
iterations, EVP_CIPHER_iv_length(cipher), iv, md)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_KEY_GEN_ERROR);
PBEPARAM_free(pbe);
return 0;
}
PBEPARAM_free(pbe);
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;
}
typedef int (*keygen_func)(EVP_CIPHER_CTX *ctx, const uint8_t *pass_raw,
size_t pass_raw_len, ASN1_TYPE *param,
const EVP_CIPHER *cipher, const EVP_MD *md,
int is_encrypt);
struct pbe_suite {
int pbe_nid;
const EVP_CIPHER* (*cipher_func)(void);
const EVP_MD* (*md_func)(void);
keygen_func keygen;
int flags;
};
#define PBE_UCS2_CONVERT_PASSWORD 0x1
static const struct pbe_suite kBuiltinPBE[] = {
{
NID_pbe_WithSHA1And40BitRC2_CBC, EVP_rc2_40_cbc, EVP_sha1,
pkcs12_pbe_keyivgen, PBE_UCS2_CONVERT_PASSWORD
},
{
NID_pbe_WithSHA1And128BitRC4, EVP_rc4, EVP_sha1, pkcs12_pbe_keyivgen,
PBE_UCS2_CONVERT_PASSWORD
},
{
NID_pbe_WithSHA1And3_Key_TripleDES_CBC, EVP_des_ede3_cbc, EVP_sha1,
pkcs12_pbe_keyivgen, PBE_UCS2_CONVERT_PASSWORD
},
{
NID_pbes2, NULL, NULL, PKCS5_v2_PBE_keyivgen, 0
},
};
static const struct pbe_suite *get_pbe_suite(int pbe_nid) {
unsigned i;
for (i = 0; i < sizeof(kBuiltinPBE) / sizeof(kBuiltinPBE[0]); i++) {
if (kBuiltinPBE[i].pbe_nid == pbe_nid) {
return &kBuiltinPBE[i];
}
}
return NULL;
}
/* pass_to_pass_raw performs a password conversion (possibly a no-op)
* appropriate to the supplied |pbe_nid|. The input |pass| is treated as a
* NUL-terminated string if |pass_len| is -1, otherwise it is treated as a
* buffer of the specified length. If the supplied PBE NID sets the
* |PBE_UCS2_CONVERT_PASSWORD| flag, the supplied |pass| will be converted to
* UCS-2.
*
* It sets |*out_pass_raw| to a new buffer that must be freed by the caller. It
* returns one on success and zero on error. */
static int pass_to_pass_raw(int pbe_nid, const char *pass, int pass_len,
uint8_t **out_pass_raw, size_t *out_pass_raw_len) {
if (pass == NULL) {
*out_pass_raw = NULL;
*out_pass_raw_len = 0;
return 1;
}
if (pass_len == -1) {
pass_len = strlen(pass);
} else if (pass_len < 0 || pass_len > 2000000000) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
return 0;
}
const struct pbe_suite *suite = get_pbe_suite(pbe_nid);
if (suite != NULL && (suite->flags & PBE_UCS2_CONVERT_PASSWORD)) {
if (!ascii_to_ucs2(pass, pass_len, out_pass_raw, out_pass_raw_len)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
return 0;
}
} else {
*out_pass_raw = BUF_memdup(pass, pass_len);
if (*out_pass_raw == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
return 0;
}
*out_pass_raw_len = (size_t)pass_len;
}
return 1;
}
static int pbe_cipher_init(ASN1_OBJECT *pbe_obj,
const uint8_t *pass_raw, size_t pass_raw_len,
ASN1_TYPE *param,
EVP_CIPHER_CTX *ctx, int is_encrypt) {
const EVP_CIPHER *cipher;
const EVP_MD *md;
const struct pbe_suite *suite = get_pbe_suite(OBJ_obj2nid(pbe_obj));
if (suite == NULL) {
char obj_str[80];
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_ALGORITHM);
if (!pbe_obj) {
strncpy(obj_str, "NULL", sizeof(obj_str));
} else {
i2t_ASN1_OBJECT(obj_str, sizeof(obj_str), pbe_obj);
}
ERR_add_error_data(2, "TYPE=", obj_str);
return 0;
}
if (suite->cipher_func == NULL) {
cipher = NULL;
} else {
cipher = suite->cipher_func();
if (!cipher) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_CIPHER);
return 0;
}
}
if (suite->md_func == NULL) {
md = NULL;
} else {
md = suite->md_func();
if (!md) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_DIGEST);
return 0;
}
}
if (!suite->keygen(ctx, pass_raw, pass_raw_len, param, cipher, md,
is_encrypt)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_KEYGEN_FAILURE);
return 0;
}
return 1;
}
static int pbe_crypt(const X509_ALGOR *algor,
const uint8_t *pass_raw, size_t pass_raw_len,
const uint8_t *in, size_t in_len,
uint8_t **out, size_t *out_len,
int is_encrypt) {
uint8_t *buf;
int n, ret = 0;
EVP_CIPHER_CTX ctx;
unsigned block_size;
EVP_CIPHER_CTX_init(&ctx);
if (!pbe_cipher_init(algor->algorithm, pass_raw, pass_raw_len,
algor->parameter, &ctx, is_encrypt)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_CIPHER_ALGORITHM);
return 0;
}
block_size = EVP_CIPHER_CTX_block_size(&ctx);
if (in_len + block_size < in_len) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_TOO_LONG);
goto err;
}
buf = OPENSSL_malloc(in_len + block_size);
if (buf == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!EVP_CipherUpdate(&ctx, buf, &n, in, in_len)) {
OPENSSL_free(buf);
OPENSSL_PUT_ERROR(PKCS8, ERR_R_EVP_LIB);
goto err;
}
*out_len = n;
if (!EVP_CipherFinal_ex(&ctx, buf + n, &n)) {
OPENSSL_free(buf);
OPENSSL_PUT_ERROR(PKCS8, ERR_R_EVP_LIB);
goto err;
}
*out_len += n;
*out = buf;
ret = 1;
err:
EVP_CIPHER_CTX_cleanup(&ctx);
return ret;
}
static void *pkcs12_item_decrypt_d2i(X509_ALGOR *algor, const ASN1_ITEM *it,
const uint8_t *pass_raw,
size_t pass_raw_len,
ASN1_OCTET_STRING *oct) {
uint8_t *out;
const uint8_t *p;
void *ret;
size_t out_len;
if (!pbe_crypt(algor, pass_raw, pass_raw_len, oct->data, oct->length,
&out, &out_len, 0 /* decrypt */)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_CRYPT_ERROR);
return NULL;
}
p = out;
ret = ASN1_item_d2i(NULL, &p, out_len, it);
OPENSSL_cleanse(out, out_len);
if (!ret) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
}
OPENSSL_free(out);
return ret;
}
PKCS8_PRIV_KEY_INFO *PKCS8_decrypt(X509_SIG *pkcs8, const char *pass,
int pass_len) {
uint8_t *pass_raw = NULL;
size_t pass_raw_len = 0;
if (!pass_to_pass_raw(OBJ_obj2nid(pkcs8->algor->algorithm), pass, pass_len,
&pass_raw, &pass_raw_len)) {
return NULL;
}
PKCS8_PRIV_KEY_INFO *ret = PKCS8_decrypt_pbe(pkcs8, pass_raw, pass_raw_len);
if (pass_raw) {
OPENSSL_cleanse(pass_raw, pass_raw_len);
OPENSSL_free(pass_raw);
}
return ret;
}
PKCS8_PRIV_KEY_INFO *PKCS8_decrypt_pbe(X509_SIG *pkcs8, const uint8_t *pass_raw,
size_t pass_raw_len) {
return pkcs12_item_decrypt_d2i(pkcs8->algor,
ASN1_ITEM_rptr(PKCS8_PRIV_KEY_INFO), pass_raw,
pass_raw_len, pkcs8->digest);
}
static ASN1_OCTET_STRING *pkcs12_item_i2d_encrypt(X509_ALGOR *algor,
const ASN1_ITEM *it,
const uint8_t *pass_raw,
size_t pass_raw_len, void *obj) {
ASN1_OCTET_STRING *oct;
uint8_t *in = NULL;
int in_len;
size_t crypt_len;
oct = M_ASN1_OCTET_STRING_new();
if (oct == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
return NULL;
}
in_len = ASN1_item_i2d(obj, &in, it);
if (!in) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_ENCODE_ERROR);
return NULL;
}
if (!pbe_crypt(algor, pass_raw, pass_raw_len, in, in_len, &oct->data, &crypt_len,
1 /* encrypt */)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_ENCRYPT_ERROR);
OPENSSL_free(in);
return NULL;
}
oct->length = crypt_len;
OPENSSL_cleanse(in, in_len);
OPENSSL_free(in);
return oct;
}
X509_SIG *PKCS8_encrypt(int pbe_nid, const EVP_CIPHER *cipher, const char *pass,
int pass_len, uint8_t *salt, size_t salt_len,
int iterations, PKCS8_PRIV_KEY_INFO *p8inf) {
uint8_t *pass_raw = NULL;
size_t pass_raw_len = 0;
if (!pass_to_pass_raw(pbe_nid, pass, pass_len, &pass_raw, &pass_raw_len)) {
return NULL;
}
X509_SIG *ret = PKCS8_encrypt_pbe(pbe_nid, cipher, pass_raw, pass_raw_len,
salt, salt_len, iterations, p8inf);
if (pass_raw) {
OPENSSL_cleanse(pass_raw, pass_raw_len);
OPENSSL_free(pass_raw);
}
return ret;
}
X509_SIG *PKCS8_encrypt_pbe(int pbe_nid, const EVP_CIPHER *cipher,
const uint8_t *pass_raw, size_t pass_raw_len,
uint8_t *salt, size_t salt_len,
int iterations, PKCS8_PRIV_KEY_INFO *p8inf) {
X509_SIG *pkcs8 = NULL;
X509_ALGOR *pbe;
pkcs8 = X509_SIG_new();
if (pkcs8 == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
goto err;
}
if (pbe_nid == -1) {
pbe = PKCS5_pbe2_set(cipher, iterations, salt, salt_len);
} else {
pbe = PKCS5_pbe_set(pbe_nid, iterations, salt, salt_len);
}
if (!pbe) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_ASN1_LIB);
goto err;
}
X509_ALGOR_free(pkcs8->algor);
pkcs8->algor = pbe;
M_ASN1_OCTET_STRING_free(pkcs8->digest);
pkcs8->digest = pkcs12_item_i2d_encrypt(
pbe, ASN1_ITEM_rptr(PKCS8_PRIV_KEY_INFO), pass_raw, pass_raw_len, p8inf);
if (!pkcs8->digest) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_ENCRYPT_ERROR);
goto err;
}
return pkcs8;
err:
X509_SIG_free(pkcs8);
return NULL;
}
EVP_PKEY *EVP_PKCS82PKEY(PKCS8_PRIV_KEY_INFO *p8) {
uint8_t *der = NULL;
int der_len = i2d_PKCS8_PRIV_KEY_INFO(p8, &der);
if (der_len < 0) {
return NULL;
}
CBS cbs;
CBS_init(&cbs, der, (size_t)der_len);
EVP_PKEY *ret = EVP_parse_private_key(&cbs);
if (ret == NULL || CBS_len(&cbs) != 0) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
EVP_PKEY_free(ret);
OPENSSL_free(der);
return NULL;
}
OPENSSL_free(der);
return ret;
}
PKCS8_PRIV_KEY_INFO *EVP_PKEY2PKCS8(EVP_PKEY *pkey) {
CBB cbb;
uint8_t *der = NULL;
size_t der_len;
if (!CBB_init(&cbb, 0) ||
!EVP_marshal_private_key(&cbb, pkey) ||
!CBB_finish(&cbb, &der, &der_len) ||
der_len > LONG_MAX) {
CBB_cleanup(&cbb);
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_ENCODE_ERROR);
goto err;
}
const uint8_t *p = der;
PKCS8_PRIV_KEY_INFO *p8 = d2i_PKCS8_PRIV_KEY_INFO(NULL, &p, (long)der_len);
if (p8 == NULL || p != der + der_len) {
PKCS8_PRIV_KEY_INFO_free(p8);
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
goto err;
}
OPENSSL_free(der);
return p8;
err:
OPENSSL_free(der);
return NULL;
}
struct pkcs12_context {
EVP_PKEY **out_key;
STACK_OF(X509) *out_certs;
uint8_t *password;
size_t password_len;
};
static int PKCS12_handle_content_info(CBS *content_info, unsigned depth,
struct pkcs12_context *ctx);
/* PKCS12_handle_content_infos parses a series of PKCS#7 ContentInfos in a
* SEQUENCE. */
static int PKCS12_handle_content_infos(CBS *content_infos,
unsigned depth,
struct pkcs12_context *ctx) {
uint8_t *der_bytes = NULL;
size_t der_len;
CBS in;
int ret = 0;
/* Generally we only expect depths 0 (the top level, with a
* pkcs7-encryptedData and a pkcs7-data) and depth 1 (the various PKCS#12
* bags). */
if (depth > 3) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_PKCS12_TOO_DEEPLY_NESTED);
return 0;
}
/* Although a BER->DER conversion is done at the beginning of |PKCS12_parse|,
* the ASN.1 data gets wrapped in OCTETSTRINGs and/or encrypted and the
* conversion cannot see through those wrappings. So each time we step
* through one we need to convert to DER again. */
if (!CBS_asn1_ber_to_der(content_infos, &der_bytes, &der_len)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
return 0;
}
if (der_bytes != NULL) {
CBS_init(&in, der_bytes, der_len);
} else {
CBS_init(&in, CBS_data(content_infos), CBS_len(content_infos));
}
if (!CBS_get_asn1(&in, &in, CBS_ASN1_SEQUENCE)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
while (CBS_len(&in) > 0) {
CBS content_info;
if (!CBS_get_asn1(&in, &content_info, CBS_ASN1_SEQUENCE)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (!PKCS12_handle_content_info(&content_info, depth + 1, ctx)) {
goto err;
}
}
/* NSS includes additional data after the SEQUENCE, but it's an (unwrapped)
* copy of the same encrypted private key (with the same IV and
* ciphertext)! */
ret = 1;
err:
OPENSSL_free(der_bytes);
return ret;
}
/* PKCS12_handle_content_info parses a single PKCS#7 ContentInfo element in a
* PKCS#12 structure. */
static int PKCS12_handle_content_info(CBS *content_info, unsigned depth,
struct pkcs12_context *ctx) {
CBS content_type, wrapped_contents, contents, content_infos;
int nid, ret = 0;
uint8_t *storage = NULL;
if (!CBS_get_asn1(content_info, &content_type, CBS_ASN1_OBJECT) ||
!CBS_get_asn1(content_info, &wrapped_contents,
CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 0)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
nid = OBJ_cbs2nid(&content_type);
if (nid == NID_pkcs7_encrypted) {
/* See https://tools.ietf.org/html/rfc2315#section-13.
*
* PKCS#7 encrypted data inside a PKCS#12 structure is generally an
* encrypted certificate bag and it's generally encrypted with 40-bit
* RC2-CBC. */
CBS version_bytes, eci, contents_type, ai, encrypted_contents;
X509_ALGOR *algor = NULL;
const uint8_t *inp;
uint8_t *out;
size_t out_len;
if (!CBS_get_asn1(&wrapped_contents, &contents, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&contents, &version_bytes, CBS_ASN1_INTEGER) ||
/* EncryptedContentInfo, see
* https://tools.ietf.org/html/rfc2315#section-10.1 */
!CBS_get_asn1(&contents, &eci, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&eci, &contents_type, CBS_ASN1_OBJECT) ||
/* AlgorithmIdentifier, see
* https://tools.ietf.org/html/rfc5280#section-4.1.1.2 */
!CBS_get_asn1_element(&eci, &ai, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1_implicit_string(
&eci, &encrypted_contents, &storage,
CBS_ASN1_CONTEXT_SPECIFIC | 0, CBS_ASN1_OCTETSTRING)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (OBJ_cbs2nid(&contents_type) != NID_pkcs7_data ||
CBS_len(&ai) > LONG_MAX) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
inp = CBS_data(&ai);
algor = d2i_X509_ALGOR(NULL, &inp, (long)CBS_len(&ai));
if (algor == NULL) {
goto err;
}
if (inp != CBS_data(&ai) + CBS_len(&ai)) {
X509_ALGOR_free(algor);
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (!pbe_crypt(algor, ctx->password, ctx->password_len,
CBS_data(&encrypted_contents), CBS_len(&encrypted_contents),
&out, &out_len, 0 /* decrypt */)) {
X509_ALGOR_free(algor);
goto err;
}
X509_ALGOR_free(algor);
CBS_init(&content_infos, out, out_len);
ret = PKCS12_handle_content_infos(&content_infos, depth + 1, ctx);
OPENSSL_free(out);
} else if (nid == NID_pkcs7_data) {
CBS octet_string_contents;
if (!CBS_get_asn1(&wrapped_contents, &octet_string_contents,
CBS_ASN1_OCTETSTRING)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
ret = PKCS12_handle_content_infos(&octet_string_contents, depth + 1, ctx);
} else if (nid == NID_pkcs8ShroudedKeyBag) {
/* See ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1.pdf, section
* 4.2.2. */
const uint8_t *inp = CBS_data(&wrapped_contents);
PKCS8_PRIV_KEY_INFO *pki = NULL;
X509_SIG *encrypted = NULL;
if (*ctx->out_key) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_MULTIPLE_PRIVATE_KEYS_IN_PKCS12);
goto err;
}
if (CBS_len(&wrapped_contents) > LONG_MAX) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
/* encrypted isn't actually an X.509 signature, but it has the same
* structure as one and so |X509_SIG| is reused to store it. */
encrypted = d2i_X509_SIG(NULL, &inp, (long)CBS_len(&wrapped_contents));
if (encrypted == NULL) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (inp != CBS_data(&wrapped_contents) + CBS_len(&wrapped_contents)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
X509_SIG_free(encrypted);
goto err;
}
pki = PKCS8_decrypt_pbe(encrypted, ctx->password, ctx->password_len);
X509_SIG_free(encrypted);
if (pki == NULL) {
goto err;
}
*ctx->out_key = EVP_PKCS82PKEY(pki);
PKCS8_PRIV_KEY_INFO_free(pki);
if (ctx->out_key == NULL) {
goto err;
}
ret = 1;
} else if (nid == NID_certBag) {
CBS cert_bag, cert_type, wrapped_cert, cert;
if (!CBS_get_asn1(&wrapped_contents, &cert_bag, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&cert_bag, &cert_type, CBS_ASN1_OBJECT) ||
!CBS_get_asn1(&cert_bag, &wrapped_cert,
CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 0) ||
!CBS_get_asn1(&wrapped_cert, &cert, CBS_ASN1_OCTETSTRING)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (OBJ_cbs2nid(&cert_type) == NID_x509Certificate) {
if (CBS_len(&cert) > LONG_MAX) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
const uint8_t *inp = CBS_data(&cert);
X509 *x509 = d2i_X509(NULL, &inp, (long)CBS_len(&cert));
if (!x509) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (inp != CBS_data(&cert) + CBS_len(&cert)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
X509_free(x509);
goto err;
}
if (0 == sk_X509_push(ctx->out_certs, x509)) {
X509_free(x509);
goto err;
}
}
ret = 1;
} else {
/* Unknown element type - ignore it. */
ret = 1;
}
err:
OPENSSL_free(storage);
return ret;
}
int PKCS12_get_key_and_certs(EVP_PKEY **out_key, STACK_OF(X509) *out_certs,
CBS *ber_in, const char *password) {
uint8_t *der_bytes = NULL;
size_t der_len;
CBS in, pfx, mac_data, authsafe, content_type, wrapped_authsafes, authsafes;
uint64_t version;
int ret = 0;
struct pkcs12_context ctx;
const size_t original_out_certs_len = sk_X509_num(out_certs);
/* The input may be in BER format. */
if (!CBS_asn1_ber_to_der(ber_in, &der_bytes, &der_len)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
return 0;
}
if (der_bytes != NULL) {
CBS_init(&in, der_bytes, der_len);
} else {
CBS_init(&in, CBS_data(ber_in), CBS_len(ber_in));
}
*out_key = NULL;
memset(&ctx, 0, sizeof(ctx));
/* See ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1.pdf, section
* four. */
if (!CBS_get_asn1(&in, &pfx, CBS_ASN1_SEQUENCE) ||
CBS_len(&in) != 0 ||
!CBS_get_asn1_uint64(&pfx, &version)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (version < 3) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_VERSION);
goto err;
}
if (!CBS_get_asn1(&pfx, &authsafe, CBS_ASN1_SEQUENCE)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
if (CBS_len(&pfx) == 0) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_MISSING_MAC);
goto err;
}
if (!CBS_get_asn1(&pfx, &mac_data, CBS_ASN1_SEQUENCE)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
/* authsafe is a PKCS#7 ContentInfo. See
* https://tools.ietf.org/html/rfc2315#section-7. */
if (!CBS_get_asn1(&authsafe, &content_type, CBS_ASN1_OBJECT) ||
!CBS_get_asn1(&authsafe, &wrapped_authsafes,
CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 0)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
/* The content type can either be |NID_pkcs7_data| or |NID_pkcs7_signed|. The
* latter indicates that it's signed by a public key, which isn't
* supported. */
if (OBJ_cbs2nid(&content_type) != NID_pkcs7_data) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_PKCS12_PUBLIC_KEY_INTEGRITY_NOT_SUPPORTED);
goto err;
}
if (!CBS_get_asn1(&wrapped_authsafes, &authsafes, CBS_ASN1_OCTETSTRING)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
ctx.out_key = out_key;
ctx.out_certs = out_certs;
if (!ascii_to_ucs2(password, password ? strlen(password) : 0, &ctx.password,
&ctx.password_len)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
goto err;
}
/* Verify the MAC. */
{
CBS mac, hash_type_seq, hash_oid, salt, expected_mac;
uint64_t iterations;
int hash_nid;
const EVP_MD *md;
uint8_t hmac_key[EVP_MAX_MD_SIZE];
uint8_t hmac[EVP_MAX_MD_SIZE];
unsigned hmac_len;
if (!CBS_get_asn1(&mac_data, &mac, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&mac, &hash_type_seq, CBS_ASN1_SEQUENCE) ||
!CBS_get_asn1(&hash_type_seq, &hash_oid, CBS_ASN1_OBJECT) ||
!CBS_get_asn1(&mac, &expected_mac, CBS_ASN1_OCTETSTRING) ||
!CBS_get_asn1(&mac_data, &salt, CBS_ASN1_OCTETSTRING)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
/* The iteration count is optional and the default is one. */
iterations = 1;
if (CBS_len(&mac_data) > 0) {
if (!CBS_get_asn1_uint64(&mac_data, &iterations) ||
iterations > INT_MAX) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_PKCS12_DATA);
goto err;
}
}
hash_nid = OBJ_cbs2nid(&hash_oid);
if (hash_nid == NID_undef ||
(md = EVP_get_digestbynid(hash_nid)) == NULL) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_HASH);
goto err;
}
if (!pkcs12_key_gen_raw(ctx.password, ctx.password_len, CBS_data(&salt),
CBS_len(&salt), PKCS12_MAC_ID, iterations,
EVP_MD_size(md), hmac_key, md)) {
goto err;
}
if (NULL == HMAC(md, hmac_key, EVP_MD_size(md), CBS_data(&authsafes),
CBS_len(&authsafes), hmac, &hmac_len)) {
goto err;
}
if (!CBS_mem_equal(&expected_mac, hmac, hmac_len)) {
OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_INCORRECT_PASSWORD);
goto err;
}
}
/* authsafes contains a series of PKCS#7 ContentInfos. */
if (!PKCS12_handle_content_infos(&authsafes, 0, &ctx)) {
goto err;
}
ret = 1;
err:
OPENSSL_free(ctx.password);
OPENSSL_free(der_bytes);
if (!ret) {
EVP_PKEY_free(*out_key);
*out_key = NULL;
while (sk_X509_num(out_certs) > original_out_certs_len) {
X509 *x509 = sk_X509_pop(out_certs);
X509_free(x509);
}
}
return ret;
}
void PKCS12_PBE_add(void) {}
struct pkcs12_st {
uint8_t *ber_bytes;
size_t ber_len;
};
PKCS12* d2i_PKCS12(PKCS12 **out_p12, const uint8_t **ber_bytes, size_t ber_len) {
PKCS12 *p12;
p12 = OPENSSL_malloc(sizeof(PKCS12));
if (!p12) {
return NULL;
}
p12->ber_bytes = OPENSSL_malloc(ber_len);
if (!p12->ber_bytes) {
OPENSSL_free(p12);
return NULL;
}
memcpy(p12->ber_bytes, *ber_bytes, ber_len);
p12->ber_len = ber_len;
*ber_bytes += ber_len;
if (out_p12) {
PKCS12_free(*out_p12);
*out_p12 = p12;
}
return p12;
}
PKCS12* d2i_PKCS12_bio(BIO *bio, PKCS12 **out_p12) {
size_t used = 0;
BUF_MEM *buf;
const uint8_t *dummy;
static const size_t kMaxSize = 256 * 1024;
PKCS12 *ret = NULL;
buf = BUF_MEM_new();
if (buf == NULL) {
return NULL;
}
if (BUF_MEM_grow(buf, 8192) == 0) {
goto out;
}
for (;;) {
int n = BIO_read(bio, &buf->data[used], buf->length - used);
if (n < 0) {
if (used == 0) {
goto out;
}
/* Workaround a bug in node.js. It uses a memory BIO for this in the wrong
* mode. */
n = 0;
}
if (n == 0) {
break;
}
used += n;
if (used < buf->length) {
continue;
}
if (buf->length > kMaxSize ||
BUF_MEM_grow(buf, buf->length * 2) == 0) {
goto out;
}
}
dummy = (uint8_t*) buf->data;
ret = d2i_PKCS12(out_p12, &dummy, used);
out:
BUF_MEM_free(buf);
return ret;
}
PKCS12* d2i_PKCS12_fp(FILE *fp, PKCS12 **out_p12) {
BIO *bio;
PKCS12 *ret;
bio = BIO_new_fp(fp, 0 /* don't take ownership */);
if (!bio) {
return NULL;
}
ret = d2i_PKCS12_bio(bio, out_p12);
BIO_free(bio);
return ret;
}
int PKCS12_parse(const PKCS12 *p12, const char *password, EVP_PKEY **out_pkey,
X509 **out_cert, STACK_OF(X509) **out_ca_certs) {
CBS ber_bytes;
STACK_OF(X509) *ca_certs = NULL;
char ca_certs_alloced = 0;
if (out_ca_certs != NULL && *out_ca_certs != NULL) {
ca_certs = *out_ca_certs;
}
if (!ca_certs) {
ca_certs = sk_X509_new_null();
if (ca_certs == NULL) {
OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
return 0;
}
ca_certs_alloced = 1;
}
CBS_init(&ber_bytes, p12->ber_bytes, p12->ber_len);
if (!PKCS12_get_key_and_certs(out_pkey, ca_certs, &ber_bytes, password)) {
if (ca_certs_alloced) {
sk_X509_free(ca_certs);
}
return 0;
}
*out_cert = NULL;
if (sk_X509_num(ca_certs) > 0) {
*out_cert = sk_X509_shift(ca_certs);
}
if (out_ca_certs) {
*out_ca_certs = ca_certs;
} else {
sk_X509_pop_free(ca_certs, X509_free);
}
return 1;
}
int PKCS12_verify_mac(const PKCS12 *p12, const char *password,
int password_len) {
if (password == NULL) {
if (password_len != 0) {
return 0;
}
} else if (password_len != -1 &&
(password[password_len] != 0 ||
memchr(password, 0, password_len) != NULL)) {
return 0;
}
EVP_PKEY *pkey = NULL;
X509 *cert = NULL;
if (!PKCS12_parse(p12, password, &pkey, &cert, NULL)) {
ERR_clear_error();
return 0;
}
EVP_PKEY_free(pkey);
X509_free(cert);
return 1;
}
void PKCS12_free(PKCS12 *p12) {
if (p12 == NULL) {
return;
}
OPENSSL_free(p12->ber_bytes);
OPENSSL_free(p12);
}
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