/*-

* Copyright (c) 2014 Michihiro NAKAJIMA

* 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.

*

* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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(S) 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.

*/

#include "archive_platform.h"

#ifdef HAVE_STRING_H

#include <string.h>

#endif

#include "archive.h"

#include "archive_cryptor_private.h"

/*

 * On systems that do not support any recognized crypto libraries,

 * this file will normally define no usable symbols.

 *

 * But some compilers and linkers choke on empty object files, so

 * define a public symbol that will always exist.  This could

 * be removed someday if this file gains another always-present

 * symbol definition.

 */

int __libarchive_cryptor_build_hack(void) {

	return 0;

}

#ifdef ARCHIVE_CRYPTOR_USE_Apple_CommonCrypto

static int

pbkdf2_sha1(const char *pw, size_t pw_len, const uint8_t *salt,

    size_t salt_len, unsigned rounds, uint8_t *derived_key,

    size_t derived_key_len)

{

	CCKeyDerivationPBKDF(kCCPBKDF2, (const char *)pw,

	    pw_len, salt, salt_len, kCCPRFHmacAlgSHA1, rounds,

	    derived_key, derived_key_len);

	return 0;

}

#elif defined(_WIN32) && !defined(__CYGWIN__) && defined(HAVE_BCRYPT_H)

#ifdef _MSC_VER

#pragma comment(lib, "Bcrypt.lib")

#endif

static int

pbkdf2_sha1(const char *pw, size_t pw_len, const uint8_t *salt,

	size_t salt_len, unsigned rounds, uint8_t *derived_key,

	size_t derived_key_len)

{

	NTSTATUS status;

	BCRYPT_ALG_HANDLE hAlg;

	status = BCryptOpenAlgorithmProvider(&hAlg, BCRYPT_SHA1_ALGORITHM,

		MS_PRIMITIVE_PROVIDER, BCRYPT_ALG_HANDLE_HMAC_FLAG);

	if (!BCRYPT_SUCCESS(status))

		return -1;

	status = BCryptDeriveKeyPBKDF2(hAlg,

		(PUCHAR)(uintptr_t)pw, (ULONG)pw_len,

		(PUCHAR)(uintptr_t)salt, (ULONG)salt_len, rounds,

		(PUCHAR)derived_key, (ULONG)derived_key_len, 0);

	BCryptCloseAlgorithmProvider(hAlg, 0);

	return (BCRYPT_SUCCESS(status)) ? 0: -1;

}

#elif defined(HAVE_LIBNETTLE) && defined(HAVE_NETTLE_PBKDF2_H)

static int

pbkdf2_sha1(const char *pw, size_t pw_len, const uint8_t *salt,

    size_t salt_len, unsigned rounds, uint8_t *derived_key,

    size_t derived_key_len) {

	pbkdf2_hmac_sha1((unsigned)pw_len, (const uint8_t *)pw, rounds,

	    salt_len, salt, derived_key_len, derived_key);

	return 0;

}

#elif defined(HAVE_LIBCRYPTO) && defined(HAVE_PKCS5_PBKDF2_HMAC_SHA1)

static int

pbkdf2_sha1(const char *pw, size_t pw_len, const uint8_t *salt,

    size_t salt_len, unsigned rounds, uint8_t *derived_key,

    size_t derived_key_len) {

	PKCS5_PBKDF2_HMAC_SHA1(pw, pw_len, salt, salt_len, rounds,

	    derived_key_len, derived_key);

	return 0;

}

#else

/* Stub */

static int

pbkdf2_sha1(const char *pw, size_t pw_len, const uint8_t *salt,

    size_t salt_len, unsigned rounds, uint8_t *derived_key,

    size_t derived_key_len) {

	(void)pw; /* UNUSED */

	(void)pw_len; /* UNUSED */

	(void)salt; /* UNUSED */

	(void)salt_len; /* UNUSED */

	(void)rounds; /* UNUSED */

	(void)derived_key; /* UNUSED */

	(void)derived_key_len; /* UNUSED */

	return -1; /* UNSUPPORTED */

}

#endif

#ifdef ARCHIVE_CRYPTOR_USE_Apple_CommonCrypto

# if MAC_OS_X_VERSION_MAX_ALLOWED < 1090

#  define kCCAlgorithmAES kCCAlgorithmAES128

# endif

static int

aes_ctr_init(archive_crypto_ctx *ctx, const uint8_t *key, size_t key_len)

{

	CCCryptorStatus r;

	ctx->key_len = key_len;

	memcpy(ctx->key, key, key_len);

	memset(ctx->nonce, 0, sizeof(ctx->nonce));

	ctx->encr_pos = AES_BLOCK_SIZE;

	r = CCCryptorCreateWithMode(kCCEncrypt, kCCModeECB, kCCAlgorithmAES,

	    ccNoPadding, NULL, key, key_len, NULL, 0, 0, 0, &ctx->ctx);

	return (r == kCCSuccess)? 0: -1;

}

static int

aes_ctr_encrypt_counter(archive_crypto_ctx *ctx)

{

	CCCryptorRef ref = ctx->ctx;

	CCCryptorStatus r;

	r = CCCryptorReset(ref, NULL);

	if (r != kCCSuccess && r != kCCUnimplemented)

		return -1;

	r = CCCryptorUpdate(ref, ctx->nonce, AES_BLOCK_SIZE, ctx->encr_buf,

	    AES_BLOCK_SIZE, NULL);

	return (r == kCCSuccess)? 0: -1;

}

static int

aes_ctr_release(archive_crypto_ctx *ctx)

{

	memset(ctx->key, 0, ctx->key_len);

	memset(ctx->nonce, 0, sizeof(ctx->nonce));

	return 0;

}

#elif defined(_WIN32) && !defined(__CYGWIN__) && defined(HAVE_BCRYPT_H)

static int

aes_ctr_init(archive_crypto_ctx *ctx, const uint8_t *key, size_t key_len)

{

	BCRYPT_ALG_HANDLE hAlg;

	BCRYPT_KEY_HANDLE hKey;

	DWORD keyObj_len, aes_key_len;

	PBYTE keyObj;

	ULONG result;

	NTSTATUS status;

	BCRYPT_KEY_LENGTHS_STRUCT key_lengths;

	ctx->hAlg = NULL;

	ctx->hKey = NULL;

	ctx->keyObj = NULL;

	switch (key_len) {

	case 16: aes_key_len = 128; break;

	case 24: aes_key_len = 192; break;

	case 32: aes_key_len = 256; break;

	default: return -1;

	}

	status = BCryptOpenAlgorithmProvider(&hAlg, BCRYPT_AES_ALGORITHM,

		MS_PRIMITIVE_PROVIDER, 0);

	if (!BCRYPT_SUCCESS(status))

		return -1;

	status = BCryptGetProperty(hAlg, BCRYPT_KEY_LENGTHS, (PUCHAR)&key_lengths,

		sizeof(key_lengths), &result, 0);

	if (!BCRYPT_SUCCESS(status)) {

		BCryptCloseAlgorithmProvider(hAlg, 0);

		return -1;

	}

	if (key_lengths.dwMinLength > aes_key_len

		|| key_lengths.dwMaxLength < aes_key_len) {

		BCryptCloseAlgorithmProvider(hAlg, 0);

		return -1;

	}

	status = BCryptGetProperty(hAlg, BCRYPT_OBJECT_LENGTH, (PUCHAR)&keyObj_len,

		sizeof(keyObj_len), &result, 0);

	if (!BCRYPT_SUCCESS(status)) {

		BCryptCloseAlgorithmProvider(hAlg, 0);

		return -1;

	}

	keyObj = (PBYTE)HeapAlloc(GetProcessHeap(), 0, keyObj_len);

	if (keyObj == NULL) {

		BCryptCloseAlgorithmProvider(hAlg, 0);

		return -1;

	}

	status = BCryptSetProperty(hAlg, BCRYPT_CHAINING_MODE,

		(PUCHAR)BCRYPT_CHAIN_MODE_ECB, sizeof(BCRYPT_CHAIN_MODE_ECB), 0);

	if (!BCRYPT_SUCCESS(status)) {

		BCryptCloseAlgorithmProvider(hAlg, 0);

		HeapFree(GetProcessHeap(), 0, keyObj);

		return -1;

	}

	status = BCryptGenerateSymmetricKey(hAlg, &hKey,

		keyObj, keyObj_len,

		(PUCHAR)(uintptr_t)key, (ULONG)key_len, 0);

	if (!BCRYPT_SUCCESS(status)) {

		BCryptCloseAlgorithmProvider(hAlg, 0);

		HeapFree(GetProcessHeap(), 0, keyObj);

		return -1;

	}

	ctx->hAlg = hAlg;

	ctx->hKey = hKey;

	ctx->keyObj = keyObj;

	ctx->keyObj_len = keyObj_len;

	ctx->encr_pos = AES_BLOCK_SIZE;

	return 0;

}

static int

aes_ctr_encrypt_counter(archive_crypto_ctx *ctx)

{

	NTSTATUS status;

	ULONG result;

	status = BCryptEncrypt(ctx->hKey, (PUCHAR)ctx->nonce, AES_BLOCK_SIZE,

		NULL, NULL, 0, (PUCHAR)ctx->encr_buf, AES_BLOCK_SIZE,

		&result, 0);

	return BCRYPT_SUCCESS(status) ? 0 : -1;

}

static int

aes_ctr_release(archive_crypto_ctx *ctx)

{

	if (ctx->hAlg != NULL) {

		BCryptCloseAlgorithmProvider(ctx->hAlg, 0);

		ctx->hAlg = NULL;

		BCryptDestroyKey(ctx->hKey);

		ctx->hKey = NULL;

		HeapFree(GetProcessHeap(), 0, ctx->keyObj);

		ctx->keyObj = NULL;

	}

	memset(ctx, 0, sizeof(*ctx));

	return 0;

}

#elif defined(HAVE_LIBNETTLE) && defined(HAVE_NETTLE_AES_H)

static int

aes_ctr_init(archive_crypto_ctx *ctx, const uint8_t *key, size_t key_len)

{

	ctx->key_len = key_len;

	memcpy(ctx->key, key, key_len);

	memset(ctx->nonce, 0, sizeof(ctx->nonce));

	ctx->encr_pos = AES_BLOCK_SIZE;

	memset(&ctx->ctx, 0, sizeof(ctx->ctx));

	return 0;

}

static int

aes_ctr_encrypt_counter(archive_crypto_ctx *ctx)

{

	aes_set_encrypt_key(&ctx->ctx, ctx->key_len, ctx->key);

	aes_encrypt(&ctx->ctx, AES_BLOCK_SIZE, ctx->encr_buf, ctx->nonce);

	return 0;

}

static int

aes_ctr_release(archive_crypto_ctx *ctx)

{

	memset(ctx, 0, sizeof(*ctx));

	return 0;

}

#elif defined(HAVE_LIBCRYPTO)

static int

aes_ctr_init(archive_crypto_ctx *ctx, const uint8_t *key, size_t key_len)

{

	if ((ctx->ctx = EVP_CIPHER_CTX_new()) == NULL)

		return -1;

	switch (key_len) {

	case 16: ctx->type = EVP_aes_128_ecb(); break;

	case 24: ctx->type = EVP_aes_192_ecb(); break;

	case 32: ctx->type = EVP_aes_256_ecb(); break;

	default: ctx->type = NULL; return -1;

	}

	ctx->key_len = key_len;

	memcpy(ctx->key, key, key_len);

	memset(ctx->nonce, 0, sizeof(ctx->nonce));

	ctx->encr_pos = AES_BLOCK_SIZE;

	EVP_CIPHER_CTX_init(ctx->ctx);

	return 0;

}

static int

aes_ctr_encrypt_counter(archive_crypto_ctx *ctx)

{

	int outl = 0;

	int r;

	r = EVP_EncryptInit_ex(ctx->ctx, ctx->type, NULL, ctx->key, NULL);

	if (r == 0)

		return -1;

	r = EVP_EncryptUpdate(ctx->ctx, ctx->encr_buf, &outl, ctx->nonce,

	    AES_BLOCK_SIZE);

	if (r == 0 || outl != AES_BLOCK_SIZE)

		return -1;

	return 0;

}

static int

aes_ctr_release(archive_crypto_ctx *ctx)

{

	EVP_CIPHER_CTX_free(ctx->ctx);

	memset(ctx->key, 0, ctx->key_len);

	memset(ctx->nonce, 0, sizeof(ctx->nonce));

	return 0;

}

#else

#define ARCHIVE_CRYPTOR_STUB

/* Stub */

static int

aes_ctr_init(archive_crypto_ctx *ctx, const uint8_t *key, size_t key_len)

{

	(void)ctx; /* UNUSED */

	(void)key; /* UNUSED */

	(void)key_len; /* UNUSED */

	return -1;

}

static int

aes_ctr_encrypt_counter(archive_crypto_ctx *ctx)

{

	(void)ctx; /* UNUSED */

	return -1;

}

static int

aes_ctr_release(archive_crypto_ctx *ctx)

{

	(void)ctx; /* UNUSED */

	return 0;

}

#endif

#ifdef ARCHIVE_CRYPTOR_STUB

static int

aes_ctr_update(archive_crypto_ctx *ctx, const uint8_t * const in,

    size_t in_len, uint8_t * const out, size_t *out_len)

{

	(void)ctx; /* UNUSED */

	(void)in; /* UNUSED */

	(void)in_len; /* UNUSED */

	(void)out; /* UNUSED */

	(void)out_len; /* UNUSED */

	aes_ctr_encrypt_counter(ctx); /* UNUSED */ /* Fix unused function warning */

	return -1;

}

#else

static void

aes_ctr_increase_counter(archive_crypto_ctx *ctx)

{

	uint8_t *const nonce = ctx->nonce;

	int j;

	for (j = 0; j < 8; j++) {

		if (++nonce[j])

			break;

	}

}

static int

aes_ctr_update(archive_crypto_ctx *ctx, const uint8_t * const in,

    size_t in_len, uint8_t * const out, size_t *out_len)

{

	uint8_t *const ebuf = ctx->encr_buf;

	unsigned pos = ctx->encr_pos;

	unsigned max = (unsigned)((in_len < *out_len)? in_len: *out_len);

	unsigned i;

	for (i = 0; i < max; ) {

		if (pos == AES_BLOCK_SIZE) {

			aes_ctr_increase_counter(ctx);

			if (aes_ctr_encrypt_counter(ctx) != 0)

				return -1;

			while (max -i >= AES_BLOCK_SIZE) {

				for (pos = 0; pos < AES_BLOCK_SIZE; pos++)

					out[i+pos] = in[i+pos] ^ ebuf[pos];

				i += AES_BLOCK_SIZE;

				aes_ctr_increase_counter(ctx);

				if (aes_ctr_encrypt_counter(ctx) != 0)

					return -1;

			}

			pos = 0;

			if (i >= max)

				break;

		}

		out[i] = in[i] ^ ebuf[pos++];

		i++;

	}

	ctx->encr_pos = pos;

	*out_len = i;

	return 0;

}

#endif /* ARCHIVE_CRYPTOR_STUB */

const struct archive_cryptor __archive_cryptor =

{

  &pbkdf2_sha1,

  &aes_ctr_init,

  &aes_ctr_update,

  &aes_ctr_release,

  &aes_ctr_init,

  &aes_ctr_update,

  &aes_ctr_release,

};