openssl/crypto/pem/pvkfmt.c
Cesar Pereida Garcia 724339ff44 Fix SCA vulnerability when using PVK and MSBLOB key formats
This commit addresses a side-channel vulnerability present when
PVK and MSBLOB key formats are loaded into OpenSSL.
The public key was not computed using a constant-time exponentiation
function.

This issue was discovered and reported by the NISEC group at TAU Finland.

Reviewed-by: Nicola Tuveri <nic.tuv@gmail.com>
Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9587)
2019-08-27 09:07:30 +01:00

886 lines
24 KiB
C

/*
* Copyright 2005-2018 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
*/
/*
* Support for PVK format keys and related structures (such a PUBLICKEYBLOB
* and PRIVATEKEYBLOB).
*/
#include "internal/cryptlib.h"
#include <openssl/pem.h>
#include <openssl/rand.h>
#include <openssl/bn.h>
#if !defined(OPENSSL_NO_RSA) && !defined(OPENSSL_NO_DSA)
# include <openssl/dsa.h>
# include <openssl/rsa.h>
/*
* Utility function: read a DWORD (4 byte unsigned integer) in little endian
* format
*/
static unsigned int read_ledword(const unsigned char **in)
{
const unsigned char *p = *in;
unsigned int ret;
ret = *p++;
ret |= (*p++ << 8);
ret |= (*p++ << 16);
ret |= (*p++ << 24);
*in = p;
return ret;
}
/*
* Read a BIGNUM in little endian format. The docs say that this should take
* up bitlen/8 bytes.
*/
static int read_lebn(const unsigned char **in, unsigned int nbyte, BIGNUM **r)
{
*r = BN_lebin2bn(*in, nbyte, NULL);
if (*r == NULL)
return 0;
*in += nbyte;
return 1;
}
/* Convert private key blob to EVP_PKEY: RSA and DSA keys supported */
# define MS_PUBLICKEYBLOB 0x6
# define MS_PRIVATEKEYBLOB 0x7
# define MS_RSA1MAGIC 0x31415352L
# define MS_RSA2MAGIC 0x32415352L
# define MS_DSS1MAGIC 0x31535344L
# define MS_DSS2MAGIC 0x32535344L
# define MS_KEYALG_RSA_KEYX 0xa400
# define MS_KEYALG_DSS_SIGN 0x2200
# define MS_KEYTYPE_KEYX 0x1
# define MS_KEYTYPE_SIGN 0x2
/* Maximum length of a blob after header */
# define BLOB_MAX_LENGTH 102400
/* The PVK file magic number: seems to spell out "bobsfile", who is Bob? */
# define MS_PVKMAGIC 0xb0b5f11eL
/* Salt length for PVK files */
# define PVK_SALTLEN 0x10
/* Maximum length in PVK header */
# define PVK_MAX_KEYLEN 102400
/* Maximum salt length */
# define PVK_MAX_SALTLEN 10240
static EVP_PKEY *b2i_rsa(const unsigned char **in,
unsigned int bitlen, int ispub);
static EVP_PKEY *b2i_dss(const unsigned char **in,
unsigned int bitlen, int ispub);
static int do_blob_header(const unsigned char **in, unsigned int length,
unsigned int *pmagic, unsigned int *pbitlen,
int *pisdss, int *pispub)
{
const unsigned char *p = *in;
if (length < 16)
return 0;
/* bType */
if (*p == MS_PUBLICKEYBLOB) {
if (*pispub == 0) {
PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PRIVATE_KEY_BLOB);
return 0;
}
*pispub = 1;
} else if (*p == MS_PRIVATEKEYBLOB) {
if (*pispub == 1) {
PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PUBLIC_KEY_BLOB);
return 0;
}
*pispub = 0;
} else
return 0;
p++;
/* Version */
if (*p++ != 0x2) {
PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_BAD_VERSION_NUMBER);
return 0;
}
/* Ignore reserved, aiKeyAlg */
p += 6;
*pmagic = read_ledword(&p);
*pbitlen = read_ledword(&p);
*pisdss = 0;
switch (*pmagic) {
case MS_DSS1MAGIC:
*pisdss = 1;
/* fall thru */
case MS_RSA1MAGIC:
if (*pispub == 0) {
PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PRIVATE_KEY_BLOB);
return 0;
}
break;
case MS_DSS2MAGIC:
*pisdss = 1;
/* fall thru */
case MS_RSA2MAGIC:
if (*pispub == 1) {
PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_EXPECTING_PUBLIC_KEY_BLOB);
return 0;
}
break;
default:
PEMerr(PEM_F_DO_BLOB_HEADER, PEM_R_BAD_MAGIC_NUMBER);
return -1;
}
*in = p;
return 1;
}
static unsigned int blob_length(unsigned bitlen, int isdss, int ispub)
{
unsigned int nbyte, hnbyte;
nbyte = (bitlen + 7) >> 3;
hnbyte = (bitlen + 15) >> 4;
if (isdss) {
/*
* Expected length: 20 for q + 3 components bitlen each + 24 for seed
* structure.
*/
if (ispub)
return 44 + 3 * nbyte;
/*
* Expected length: 20 for q, priv, 2 bitlen components + 24 for seed
* structure.
*/
else
return 64 + 2 * nbyte;
} else {
/* Expected length: 4 for 'e' + 'n' */
if (ispub)
return 4 + nbyte;
else
/*
* Expected length: 4 for 'e' and 7 other components. 2
* components are bitlen size, 5 are bitlen/2
*/
return 4 + 2 * nbyte + 5 * hnbyte;
}
}
static EVP_PKEY *do_b2i(const unsigned char **in, unsigned int length,
int ispub)
{
const unsigned char *p = *in;
unsigned int bitlen, magic;
int isdss;
if (do_blob_header(&p, length, &magic, &bitlen, &isdss, &ispub) <= 0) {
PEMerr(PEM_F_DO_B2I, PEM_R_KEYBLOB_HEADER_PARSE_ERROR);
return NULL;
}
length -= 16;
if (length < blob_length(bitlen, isdss, ispub)) {
PEMerr(PEM_F_DO_B2I, PEM_R_KEYBLOB_TOO_SHORT);
return NULL;
}
if (isdss)
return b2i_dss(&p, bitlen, ispub);
else
return b2i_rsa(&p, bitlen, ispub);
}
static EVP_PKEY *do_b2i_bio(BIO *in, int ispub)
{
const unsigned char *p;
unsigned char hdr_buf[16], *buf = NULL;
unsigned int bitlen, magic, length;
int isdss;
EVP_PKEY *ret = NULL;
if (BIO_read(in, hdr_buf, 16) != 16) {
PEMerr(PEM_F_DO_B2I_BIO, PEM_R_KEYBLOB_TOO_SHORT);
return NULL;
}
p = hdr_buf;
if (do_blob_header(&p, 16, &magic, &bitlen, &isdss, &ispub) <= 0)
return NULL;
length = blob_length(bitlen, isdss, ispub);
if (length > BLOB_MAX_LENGTH) {
PEMerr(PEM_F_DO_B2I_BIO, PEM_R_HEADER_TOO_LONG);
return NULL;
}
buf = OPENSSL_malloc(length);
if (buf == NULL) {
PEMerr(PEM_F_DO_B2I_BIO, ERR_R_MALLOC_FAILURE);
goto err;
}
p = buf;
if (BIO_read(in, buf, length) != (int)length) {
PEMerr(PEM_F_DO_B2I_BIO, PEM_R_KEYBLOB_TOO_SHORT);
goto err;
}
if (isdss)
ret = b2i_dss(&p, bitlen, ispub);
else
ret = b2i_rsa(&p, bitlen, ispub);
err:
OPENSSL_free(buf);
return ret;
}
static EVP_PKEY *b2i_dss(const unsigned char **in,
unsigned int bitlen, int ispub)
{
const unsigned char *p = *in;
EVP_PKEY *ret = NULL;
DSA *dsa = NULL;
BN_CTX *ctx = NULL;
unsigned int nbyte;
BIGNUM *pbn = NULL, *qbn = NULL, *gbn = NULL, *priv_key = NULL;
BIGNUM *pub_key = NULL;
nbyte = (bitlen + 7) >> 3;
dsa = DSA_new();
ret = EVP_PKEY_new();
if (dsa == NULL || ret == NULL)
goto memerr;
if (!read_lebn(&p, nbyte, &pbn))
goto memerr;
if (!read_lebn(&p, 20, &qbn))
goto memerr;
if (!read_lebn(&p, nbyte, &gbn))
goto memerr;
if (ispub) {
if (!read_lebn(&p, nbyte, &pub_key))
goto memerr;
} else {
if (!read_lebn(&p, 20, &priv_key))
goto memerr;
/* Set constant time flag before public key calculation */
BN_set_flags(priv_key, BN_FLG_CONSTTIME);
/* Calculate public key */
pub_key = BN_new();
if (pub_key == NULL)
goto memerr;
if ((ctx = BN_CTX_new()) == NULL)
goto memerr;
if (!BN_mod_exp(pub_key, gbn, priv_key, pbn, ctx))
goto memerr;
BN_CTX_free(ctx);
ctx = NULL;
}
if (!DSA_set0_pqg(dsa, pbn, qbn, gbn))
goto memerr;
pbn = qbn = gbn = NULL;
if (!DSA_set0_key(dsa, pub_key, priv_key))
goto memerr;
pub_key = priv_key = NULL;
if (!EVP_PKEY_set1_DSA(ret, dsa))
goto memerr;
DSA_free(dsa);
*in = p;
return ret;
memerr:
PEMerr(PEM_F_B2I_DSS, ERR_R_MALLOC_FAILURE);
DSA_free(dsa);
BN_free(pbn);
BN_free(qbn);
BN_free(gbn);
BN_free(pub_key);
BN_free(priv_key);
EVP_PKEY_free(ret);
BN_CTX_free(ctx);
return NULL;
}
static EVP_PKEY *b2i_rsa(const unsigned char **in,
unsigned int bitlen, int ispub)
{
const unsigned char *pin = *in;
EVP_PKEY *ret = NULL;
BIGNUM *e = NULL, *n = NULL, *d = NULL;
BIGNUM *p = NULL, *q = NULL, *dmp1 = NULL, *dmq1 = NULL, *iqmp = NULL;
RSA *rsa = NULL;
unsigned int nbyte, hnbyte;
nbyte = (bitlen + 7) >> 3;
hnbyte = (bitlen + 15) >> 4;
rsa = RSA_new();
ret = EVP_PKEY_new();
if (rsa == NULL || ret == NULL)
goto memerr;
e = BN_new();
if (e == NULL)
goto memerr;
if (!BN_set_word(e, read_ledword(&pin)))
goto memerr;
if (!read_lebn(&pin, nbyte, &n))
goto memerr;
if (!ispub) {
if (!read_lebn(&pin, hnbyte, &p))
goto memerr;
if (!read_lebn(&pin, hnbyte, &q))
goto memerr;
if (!read_lebn(&pin, hnbyte, &dmp1))
goto memerr;
if (!read_lebn(&pin, hnbyte, &dmq1))
goto memerr;
if (!read_lebn(&pin, hnbyte, &iqmp))
goto memerr;
if (!read_lebn(&pin, nbyte, &d))
goto memerr;
if (!RSA_set0_factors(rsa, p, q))
goto memerr;
p = q = NULL;
if (!RSA_set0_crt_params(rsa, dmp1, dmq1, iqmp))
goto memerr;
dmp1 = dmq1 = iqmp = NULL;
}
if (!RSA_set0_key(rsa, n, e, d))
goto memerr;
n = e = d = NULL;
if (!EVP_PKEY_set1_RSA(ret, rsa))
goto memerr;
RSA_free(rsa);
*in = pin;
return ret;
memerr:
PEMerr(PEM_F_B2I_RSA, ERR_R_MALLOC_FAILURE);
BN_free(e);
BN_free(n);
BN_free(p);
BN_free(q);
BN_free(dmp1);
BN_free(dmq1);
BN_free(iqmp);
BN_free(d);
RSA_free(rsa);
EVP_PKEY_free(ret);
return NULL;
}
EVP_PKEY *b2i_PrivateKey(const unsigned char **in, long length)
{
return do_b2i(in, length, 0);
}
EVP_PKEY *b2i_PublicKey(const unsigned char **in, long length)
{
return do_b2i(in, length, 1);
}
EVP_PKEY *b2i_PrivateKey_bio(BIO *in)
{
return do_b2i_bio(in, 0);
}
EVP_PKEY *b2i_PublicKey_bio(BIO *in)
{
return do_b2i_bio(in, 1);
}
static void write_ledword(unsigned char **out, unsigned int dw)
{
unsigned char *p = *out;
*p++ = dw & 0xff;
*p++ = (dw >> 8) & 0xff;
*p++ = (dw >> 16) & 0xff;
*p++ = (dw >> 24) & 0xff;
*out = p;
}
static void write_lebn(unsigned char **out, const BIGNUM *bn, int len)
{
BN_bn2lebinpad(bn, *out, len);
*out += len;
}
static int check_bitlen_rsa(RSA *rsa, int ispub, unsigned int *magic);
static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *magic);
static void write_rsa(unsigned char **out, RSA *rsa, int ispub);
static void write_dsa(unsigned char **out, DSA *dsa, int ispub);
static int do_i2b(unsigned char **out, EVP_PKEY *pk, int ispub)
{
unsigned char *p;
unsigned int bitlen, magic = 0, keyalg;
int outlen, noinc = 0;
int pktype = EVP_PKEY_id(pk);
if (pktype == EVP_PKEY_DSA) {
bitlen = check_bitlen_dsa(EVP_PKEY_get0_DSA(pk), ispub, &magic);
keyalg = MS_KEYALG_DSS_SIGN;
} else if (pktype == EVP_PKEY_RSA) {
bitlen = check_bitlen_rsa(EVP_PKEY_get0_RSA(pk), ispub, &magic);
keyalg = MS_KEYALG_RSA_KEYX;
} else
return -1;
if (bitlen == 0)
return -1;
outlen = 16 + blob_length(bitlen,
keyalg == MS_KEYALG_DSS_SIGN ? 1 : 0, ispub);
if (out == NULL)
return outlen;
if (*out)
p = *out;
else {
if ((p = OPENSSL_malloc(outlen)) == NULL) {
PEMerr(PEM_F_DO_I2B, ERR_R_MALLOC_FAILURE);
return -1;
}
*out = p;
noinc = 1;
}
if (ispub)
*p++ = MS_PUBLICKEYBLOB;
else
*p++ = MS_PRIVATEKEYBLOB;
*p++ = 0x2;
*p++ = 0;
*p++ = 0;
write_ledword(&p, keyalg);
write_ledword(&p, magic);
write_ledword(&p, bitlen);
if (keyalg == MS_KEYALG_DSS_SIGN)
write_dsa(&p, EVP_PKEY_get0_DSA(pk), ispub);
else
write_rsa(&p, EVP_PKEY_get0_RSA(pk), ispub);
if (!noinc)
*out += outlen;
return outlen;
}
static int do_i2b_bio(BIO *out, EVP_PKEY *pk, int ispub)
{
unsigned char *tmp = NULL;
int outlen, wrlen;
outlen = do_i2b(&tmp, pk, ispub);
if (outlen < 0)
return -1;
wrlen = BIO_write(out, tmp, outlen);
OPENSSL_free(tmp);
if (wrlen == outlen)
return outlen;
return -1;
}
static int check_bitlen_dsa(DSA *dsa, int ispub, unsigned int *pmagic)
{
int bitlen;
const BIGNUM *p = NULL, *q = NULL, *g = NULL;
const BIGNUM *pub_key = NULL, *priv_key = NULL;
DSA_get0_pqg(dsa, &p, &q, &g);
DSA_get0_key(dsa, &pub_key, &priv_key);
bitlen = BN_num_bits(p);
if ((bitlen & 7) || (BN_num_bits(q) != 160)
|| (BN_num_bits(g) > bitlen))
goto badkey;
if (ispub) {
if (BN_num_bits(pub_key) > bitlen)
goto badkey;
*pmagic = MS_DSS1MAGIC;
} else {
if (BN_num_bits(priv_key) > 160)
goto badkey;
*pmagic = MS_DSS2MAGIC;
}
return bitlen;
badkey:
PEMerr(PEM_F_CHECK_BITLEN_DSA, PEM_R_UNSUPPORTED_KEY_COMPONENTS);
return 0;
}
static int check_bitlen_rsa(RSA *rsa, int ispub, unsigned int *pmagic)
{
int nbyte, hnbyte, bitlen;
const BIGNUM *e;
RSA_get0_key(rsa, NULL, &e, NULL);
if (BN_num_bits(e) > 32)
goto badkey;
bitlen = RSA_bits(rsa);
nbyte = RSA_size(rsa);
hnbyte = (bitlen + 15) >> 4;
if (ispub) {
*pmagic = MS_RSA1MAGIC;
return bitlen;
} else {
const BIGNUM *d, *p, *q, *iqmp, *dmp1, *dmq1;
*pmagic = MS_RSA2MAGIC;
/*
* For private key each component must fit within nbyte or hnbyte.
*/
RSA_get0_key(rsa, NULL, NULL, &d);
if (BN_num_bytes(d) > nbyte)
goto badkey;
RSA_get0_factors(rsa, &p, &q);
RSA_get0_crt_params(rsa, &dmp1, &dmq1, &iqmp);
if ((BN_num_bytes(iqmp) > hnbyte)
|| (BN_num_bytes(p) > hnbyte)
|| (BN_num_bytes(q) > hnbyte)
|| (BN_num_bytes(dmp1) > hnbyte)
|| (BN_num_bytes(dmq1) > hnbyte))
goto badkey;
}
return bitlen;
badkey:
PEMerr(PEM_F_CHECK_BITLEN_RSA, PEM_R_UNSUPPORTED_KEY_COMPONENTS);
return 0;
}
static void write_rsa(unsigned char **out, RSA *rsa, int ispub)
{
int nbyte, hnbyte;
const BIGNUM *n, *d, *e, *p, *q, *iqmp, *dmp1, *dmq1;
nbyte = RSA_size(rsa);
hnbyte = (RSA_bits(rsa) + 15) >> 4;
RSA_get0_key(rsa, &n, &e, &d);
write_lebn(out, e, 4);
write_lebn(out, n, nbyte);
if (ispub)
return;
RSA_get0_factors(rsa, &p, &q);
RSA_get0_crt_params(rsa, &dmp1, &dmq1, &iqmp);
write_lebn(out, p, hnbyte);
write_lebn(out, q, hnbyte);
write_lebn(out, dmp1, hnbyte);
write_lebn(out, dmq1, hnbyte);
write_lebn(out, iqmp, hnbyte);
write_lebn(out, d, nbyte);
}
static void write_dsa(unsigned char **out, DSA *dsa, int ispub)
{
int nbyte;
const BIGNUM *p = NULL, *q = NULL, *g = NULL;
const BIGNUM *pub_key = NULL, *priv_key = NULL;
DSA_get0_pqg(dsa, &p, &q, &g);
DSA_get0_key(dsa, &pub_key, &priv_key);
nbyte = BN_num_bytes(p);
write_lebn(out, p, nbyte);
write_lebn(out, q, 20);
write_lebn(out, g, nbyte);
if (ispub)
write_lebn(out, pub_key, nbyte);
else
write_lebn(out, priv_key, 20);
/* Set "invalid" for seed structure values */
memset(*out, 0xff, 24);
*out += 24;
return;
}
int i2b_PrivateKey_bio(BIO *out, EVP_PKEY *pk)
{
return do_i2b_bio(out, pk, 0);
}
int i2b_PublicKey_bio(BIO *out, EVP_PKEY *pk)
{
return do_i2b_bio(out, pk, 1);
}
# ifndef OPENSSL_NO_RC4
static int do_PVK_header(const unsigned char **in, unsigned int length,
int skip_magic,
unsigned int *psaltlen, unsigned int *pkeylen)
{
const unsigned char *p = *in;
unsigned int pvk_magic, is_encrypted;
if (skip_magic) {
if (length < 20) {
PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
return 0;
}
} else {
if (length < 24) {
PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_PVK_TOO_SHORT);
return 0;
}
pvk_magic = read_ledword(&p);
if (pvk_magic != MS_PVKMAGIC) {
PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_BAD_MAGIC_NUMBER);
return 0;
}
}
/* Skip reserved */
p += 4;
/*
* keytype =
*/ read_ledword(&p);
is_encrypted = read_ledword(&p);
*psaltlen = read_ledword(&p);
*pkeylen = read_ledword(&p);
if (*pkeylen > PVK_MAX_KEYLEN || *psaltlen > PVK_MAX_SALTLEN)
return 0;
if (is_encrypted && !*psaltlen) {
PEMerr(PEM_F_DO_PVK_HEADER, PEM_R_INCONSISTENT_HEADER);
return 0;
}
*in = p;
return 1;
}
static int derive_pvk_key(unsigned char *key,
const unsigned char *salt, unsigned int saltlen,
const unsigned char *pass, int passlen)
{
EVP_MD_CTX *mctx = EVP_MD_CTX_new();
int rv = 1;
if (mctx == NULL
|| !EVP_DigestInit_ex(mctx, EVP_sha1(), NULL)
|| !EVP_DigestUpdate(mctx, salt, saltlen)
|| !EVP_DigestUpdate(mctx, pass, passlen)
|| !EVP_DigestFinal_ex(mctx, key, NULL))
rv = 0;
EVP_MD_CTX_free(mctx);
return rv;
}
static EVP_PKEY *do_PVK_body(const unsigned char **in,
unsigned int saltlen, unsigned int keylen,
pem_password_cb *cb, void *u)
{
EVP_PKEY *ret = NULL;
const unsigned char *p = *in;
unsigned int magic;
unsigned char *enctmp = NULL, *q;
unsigned char keybuf[20];
EVP_CIPHER_CTX *cctx = EVP_CIPHER_CTX_new();
if (saltlen) {
char psbuf[PEM_BUFSIZE];
int enctmplen, inlen;
if (cb)
inlen = cb(psbuf, PEM_BUFSIZE, 0, u);
else
inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 0, u);
if (inlen < 0) {
PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_PASSWORD_READ);
goto err;
}
enctmp = OPENSSL_malloc(keylen + 8);
if (enctmp == NULL) {
PEMerr(PEM_F_DO_PVK_BODY, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!derive_pvk_key(keybuf, p, saltlen,
(unsigned char *)psbuf, inlen))
goto err;
p += saltlen;
/* Copy BLOBHEADER across, decrypt rest */
memcpy(enctmp, p, 8);
p += 8;
if (keylen < 8) {
PEMerr(PEM_F_DO_PVK_BODY, PEM_R_PVK_TOO_SHORT);
goto err;
}
inlen = keylen - 8;
q = enctmp + 8;
if (!EVP_DecryptInit_ex(cctx, EVP_rc4(), NULL, keybuf, NULL))
goto err;
if (!EVP_DecryptUpdate(cctx, q, &enctmplen, p, inlen))
goto err;
if (!EVP_DecryptFinal_ex(cctx, q + enctmplen, &enctmplen))
goto err;
magic = read_ledword((const unsigned char **)&q);
if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
q = enctmp + 8;
memset(keybuf + 5, 0, 11);
if (!EVP_DecryptInit_ex(cctx, EVP_rc4(), NULL, keybuf, NULL))
goto err;
if (!EVP_DecryptUpdate(cctx, q, &enctmplen, p, inlen))
goto err;
if (!EVP_DecryptFinal_ex(cctx, q + enctmplen, &enctmplen))
goto err;
magic = read_ledword((const unsigned char **)&q);
if (magic != MS_RSA2MAGIC && magic != MS_DSS2MAGIC) {
PEMerr(PEM_F_DO_PVK_BODY, PEM_R_BAD_DECRYPT);
goto err;
}
}
p = enctmp;
}
ret = b2i_PrivateKey(&p, keylen);
err:
EVP_CIPHER_CTX_free(cctx);
if (enctmp != NULL) {
OPENSSL_cleanse(keybuf, sizeof(keybuf));
OPENSSL_free(enctmp);
}
return ret;
}
EVP_PKEY *b2i_PVK_bio(BIO *in, pem_password_cb *cb, void *u)
{
unsigned char pvk_hdr[24], *buf = NULL;
const unsigned char *p;
int buflen;
EVP_PKEY *ret = NULL;
unsigned int saltlen, keylen;
if (BIO_read(in, pvk_hdr, 24) != 24) {
PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
return NULL;
}
p = pvk_hdr;
if (!do_PVK_header(&p, 24, 0, &saltlen, &keylen))
return 0;
buflen = (int)keylen + saltlen;
buf = OPENSSL_malloc(buflen);
if (buf == NULL) {
PEMerr(PEM_F_B2I_PVK_BIO, ERR_R_MALLOC_FAILURE);
return 0;
}
p = buf;
if (BIO_read(in, buf, buflen) != buflen) {
PEMerr(PEM_F_B2I_PVK_BIO, PEM_R_PVK_DATA_TOO_SHORT);
goto err;
}
ret = do_PVK_body(&p, saltlen, keylen, cb, u);
err:
OPENSSL_clear_free(buf, buflen);
return ret;
}
static int i2b_PVK(unsigned char **out, EVP_PKEY *pk, int enclevel,
pem_password_cb *cb, void *u)
{
int outlen = 24, pklen;
unsigned char *p = NULL, *start = NULL, *salt = NULL;
EVP_CIPHER_CTX *cctx = NULL;
if (enclevel)
outlen += PVK_SALTLEN;
pklen = do_i2b(NULL, pk, 0);
if (pklen < 0)
return -1;
outlen += pklen;
if (out == NULL)
return outlen;
if (*out != NULL) {
p = *out;
} else {
start = p = OPENSSL_malloc(outlen);
if (p == NULL) {
PEMerr(PEM_F_I2B_PVK, ERR_R_MALLOC_FAILURE);
return -1;
}
}
cctx = EVP_CIPHER_CTX_new();
if (cctx == NULL)
goto error;
write_ledword(&p, MS_PVKMAGIC);
write_ledword(&p, 0);
if (EVP_PKEY_id(pk) == EVP_PKEY_DSA)
write_ledword(&p, MS_KEYTYPE_SIGN);
else
write_ledword(&p, MS_KEYTYPE_KEYX);
write_ledword(&p, enclevel ? 1 : 0);
write_ledword(&p, enclevel ? PVK_SALTLEN : 0);
write_ledword(&p, pklen);
if (enclevel) {
if (RAND_bytes(p, PVK_SALTLEN) <= 0)
goto error;
salt = p;
p += PVK_SALTLEN;
}
do_i2b(&p, pk, 0);
if (enclevel != 0) {
char psbuf[PEM_BUFSIZE];
unsigned char keybuf[20];
int enctmplen, inlen;
if (cb)
inlen = cb(psbuf, PEM_BUFSIZE, 1, u);
else
inlen = PEM_def_callback(psbuf, PEM_BUFSIZE, 1, u);
if (inlen <= 0) {
PEMerr(PEM_F_I2B_PVK, PEM_R_BAD_PASSWORD_READ);
goto error;
}
if (!derive_pvk_key(keybuf, salt, PVK_SALTLEN,
(unsigned char *)psbuf, inlen))
goto error;
if (enclevel == 1)
memset(keybuf + 5, 0, 11);
p = salt + PVK_SALTLEN + 8;
if (!EVP_EncryptInit_ex(cctx, EVP_rc4(), NULL, keybuf, NULL))
goto error;
OPENSSL_cleanse(keybuf, 20);
if (!EVP_DecryptUpdate(cctx, p, &enctmplen, p, pklen - 8))
goto error;
if (!EVP_DecryptFinal_ex(cctx, p + enctmplen, &enctmplen))
goto error;
}
EVP_CIPHER_CTX_free(cctx);
if (*out == NULL)
*out = start;
return outlen;
error:
EVP_CIPHER_CTX_free(cctx);
if (*out == NULL)
OPENSSL_free(start);
return -1;
}
int i2b_PVK_bio(BIO *out, EVP_PKEY *pk, int enclevel,
pem_password_cb *cb, void *u)
{
unsigned char *tmp = NULL;
int outlen, wrlen;
outlen = i2b_PVK(&tmp, pk, enclevel, cb, u);
if (outlen < 0)
return -1;
wrlen = BIO_write(out, tmp, outlen);
OPENSSL_free(tmp);
if (wrlen == outlen) {
PEMerr(PEM_F_I2B_PVK_BIO, PEM_R_BIO_WRITE_FAILURE);
return outlen;
}
return -1;
}
# endif
#endif