/* $OpenBSD: pem_pkey.c,v 1.21 2015/09/10 15:56:25 jsing Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * 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 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 acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS 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 AUTHOR OR 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.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <string.h>

#include <openssl/opensslconf.h>

#include <openssl/buffer.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/objects.h>
#include <openssl/pem.h>
#include <openssl/pkcs12.h>
#include <openssl/x509.h>

#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif

#include "asn1_locl.h"

int pem_check_suffix(const char *pem_str, const char *suffix);

EVP_PKEY *
PEM_read_bio_PrivateKey(BIO *bp, EVP_PKEY **x, pem_password_cb *cb, void *u)
{
	char *nm = NULL;
	const unsigned char *p = NULL;
	unsigned char *data = NULL;
	long len;
	int slen;
	EVP_PKEY *ret = NULL;

	if (!PEM_bytes_read_bio(&data, &len, &nm, PEM_STRING_EVP_PKEY,
	    bp, cb, u))
		return NULL;
	p = data;

	if (strcmp(nm, PEM_STRING_PKCS8INF) == 0) {
		PKCS8_PRIV_KEY_INFO *p8inf;
		p8inf = d2i_PKCS8_PRIV_KEY_INFO(NULL, &p, len);
		if (!p8inf)
			goto p8err;
		ret = EVP_PKCS82PKEY(p8inf);
		if (x) {
			EVP_PKEY_free(*x);
			*x = ret;
		}
		PKCS8_PRIV_KEY_INFO_free(p8inf);
	} else if (strcmp(nm, PEM_STRING_PKCS8) == 0) {
		PKCS8_PRIV_KEY_INFO *p8inf;
		X509_SIG *p8;
		int klen;
		char psbuf[PEM_BUFSIZE];
		p8 = d2i_X509_SIG(NULL, &p, len);
		if (!p8)
			goto p8err;
		if (cb)
			klen = cb(psbuf, PEM_BUFSIZE, 0, u);
		else
			klen = PEM_def_callback(psbuf, PEM_BUFSIZE, 0, u);
		if (klen <= 0) {
			PEMerr(PEM_F_PEM_READ_BIO_PRIVATEKEY,
			    PEM_R_BAD_PASSWORD_READ);
			X509_SIG_free(p8);
			goto err;
		}
		p8inf = PKCS8_decrypt(p8, psbuf, klen);
		X509_SIG_free(p8);
		if (!p8inf)
			goto p8err;
		ret = EVP_PKCS82PKEY(p8inf);
		if (x) {
			EVP_PKEY_free(*x);
			*x = ret;
		}
		PKCS8_PRIV_KEY_INFO_free(p8inf);
	} else if ((slen = pem_check_suffix(nm, "PRIVATE KEY")) > 0) {
		const EVP_PKEY_ASN1_METHOD *ameth;
		ameth = EVP_PKEY_asn1_find_str(NULL, nm, slen);
		if (!ameth || !ameth->old_priv_decode)
			goto p8err;
		ret = d2i_PrivateKey(ameth->pkey_id, x, &p, len);
	}

p8err:
	if (ret == NULL)
		PEMerr(PEM_F_PEM_READ_BIO_PRIVATEKEY, ERR_R_ASN1_LIB);
err:
	free(nm);
	explicit_bzero(data, len);
	free(data);
	return (ret);
}

int
PEM_write_bio_PrivateKey(BIO *bp, EVP_PKEY *x, const EVP_CIPHER *enc,
    unsigned char *kstr, int klen, pem_password_cb *cb, void *u)
{
	char pem_str[80];

	if (!x->ameth || x->ameth->priv_encode)
		return PEM_write_bio_PKCS8PrivateKey(bp, x, enc,
		    (char *)kstr, klen, cb, u);

	(void) snprintf(pem_str, sizeof(pem_str), "%s PRIVATE KEY",
	    x->ameth->pem_str);
	return PEM_ASN1_write_bio((i2d_of_void *)i2d_PrivateKey,
	    pem_str, bp, x, enc, kstr, klen, cb, u);
}

EVP_PKEY *
PEM_read_bio_Parameters(BIO *bp, EVP_PKEY **x)
{
	char *nm = NULL;
	const unsigned char *p = NULL;
	unsigned char *data = NULL;
	long len;
	int slen;
	EVP_PKEY *ret = NULL;

	if (!PEM_bytes_read_bio(&data, &len, &nm, PEM_STRING_PARAMETERS,
	    bp, 0, NULL))
		return NULL;
	p = data;

	if ((slen = pem_check_suffix(nm, "PARAMETERS")) > 0) {
		ret = EVP_PKEY_new();
		if (!ret)
			goto err;
		if (!EVP_PKEY_set_type_str(ret, nm, slen) ||
		    !ret->ameth->param_decode ||
		    !ret->ameth->param_decode(ret, &p, len)) {
			EVP_PKEY_free(ret);
			ret = NULL;
			goto err;
		}
		if (x) {
			EVP_PKEY_free(*x);
			*x = ret;
		}
	}

err:
	if (ret == NULL)
		PEMerr(PEM_F_PEM_READ_BIO_PARAMETERS, ERR_R_ASN1_LIB);
	free(nm);
	free(data);
	return (ret);
}

int
PEM_write_bio_Parameters(BIO *bp, EVP_PKEY *x)
{
	char pem_str[80];

	if (!x->ameth || !x->ameth->param_encode)
		return 0;

	(void) snprintf(pem_str, sizeof(pem_str), "%s PARAMETERS",
	    x->ameth->pem_str);
	return PEM_ASN1_write_bio((i2d_of_void *)x->ameth->param_encode,
	    pem_str, bp, x, NULL, NULL, 0, 0, NULL);
}

EVP_PKEY *
PEM_read_PrivateKey(FILE *fp, EVP_PKEY **x, pem_password_cb *cb, void *u)
{
	BIO *b;
	EVP_PKEY *ret;

	if ((b = BIO_new(BIO_s_file())) == NULL) {
		PEMerr(PEM_F_PEM_READ_PRIVATEKEY, ERR_R_BUF_LIB);
		return (0);
	}
	BIO_set_fp(b, fp, BIO_NOCLOSE);
	ret = PEM_read_bio_PrivateKey(b, x, cb, u);
	BIO_free(b);
	return (ret);
}

int
PEM_write_PrivateKey(FILE *fp, EVP_PKEY *x, const EVP_CIPHER *enc,
    unsigned char *kstr, int klen, pem_password_cb *cb, void *u)
{
	BIO *b;
	int ret;

	if ((b = BIO_new_fp(fp, BIO_NOCLOSE)) == NULL) {
		PEMerr(PEM_F_PEM_WRITE_PRIVATEKEY, ERR_R_BUF_LIB);
		return 0;
	}
	ret = PEM_write_bio_PrivateKey(b, x, enc, kstr, klen, cb, u);
	BIO_free(b);
	return ret;
}