crypto/modes/cts128.c - third_party/openssl - Git at Google

 /* ====================================================================
  * Copyright (c) 2008 The OpenSSL Project. All rights reserved.
  *
  * Rights for redistribution and usage in source and binary
  * forms are granted according to the OpenSSL license.
  */

 #include "modes.h"
 #include <string.h>

 #ifndef MODES_DEBUG
 # ifndef NDEBUG
 #  define NDEBUG
 # endif
 #endif
 #include <assert.h>

 /*
  * Trouble with Ciphertext Stealing, CTS, mode is that there is no
  * common official specification, but couple of cipher/application
  * specific ones: RFC2040 and RFC3962. Then there is 'Proposal to
  * Extend CBC Mode By "Ciphertext Stealing"' at NIST site, which
  * deviates from mentioned RFCs. Most notably it allows input to be
  * of block length and it doesn't flip the order of the last two
  * blocks. CTS is being discussed even in ECB context, but it's not
  * adopted for any known application. This implementation complies
  * with mentioned RFCs and [as such] extends CBC mode.
  */

 size_t CRYPTO_cts128_encrypt_block(const unsigned char *in, unsigned char *out,
 			size_t len, const void *key,
 			unsigned char ivec[16], block128_f block)
 {	size_t residue, n;

 	assert (in && out && key && ivec);

 	if (len <= 16) return 0;

 	if ((residue=len%16) == 0) residue = 16;

 	len -= residue;

 	CRYPTO_cbc128_encrypt(in,out,len,key,ivec,block);

 	in  += len;
 	out += len;

 	for (n=0; n<residue; ++n)
 		ivec[n] ^= in[n];
 	(*block)(ivec,ivec,key);
 	memcpy(out,out-16,residue);
 	memcpy(out-16,ivec,16);

 	return len+residue;
 }

 size_t CRYPTO_cts128_encrypt(const unsigned char *in, unsigned char *out,
 			size_t len, const void *key,
 			unsigned char ivec[16], cbc128_f cbc)
 {	size_t residue;
 	union { size_t align; unsigned char c[16]; } tmp;

 	assert (in && out && key && ivec);

 	if (len <= 16) return 0;

 	if ((residue=len%16) == 0) residue = 16;

 	len -= residue;

 	(*cbc)(in,out,len,key,ivec,1);

 	in  += len;
 	out += len;

 #if defined(CBC_HANDLES_TRUNCATED_IO)
 	memcpy(tmp.c,out-16,16);
 	(*cbc)(in,out-16,residue,key,ivec,1);
 	memcpy(out,tmp.c,residue);
 #else
 	{
 	size_t n;
 	for (n=0; n<16; n+=sizeof(size_t))
 		*(size_t *)(tmp.c+n) = 0;
 	memcpy(tmp.c,in,residue);
 	}
 	memcpy(out,out-16,residue);
 	(*cbc)(tmp.c,out-16,16,key,ivec,1);
 #endif
 	return len+residue;
 }

 size_t CRYPTO_cts128_decrypt_block(const unsigned char *in, unsigned char *out,
 			size_t len, const void *key,
 			unsigned char ivec[16], block128_f block)
 {	size_t residue, n;
 	union { size_t align; unsigned char c[32]; } tmp;

 	assert (in && out && key && ivec);

 	if (len<=16) return 0;

 	if ((residue=len%16) == 0) residue = 16;

 	len -= 16+residue;

 	if (len) {
 		CRYPTO_cbc128_decrypt(in,out,len,key,ivec,block);
 		in  += len;
 		out += len;
 	}

 	(*block)(in,tmp.c+16,key);

 	for (n=0; n<16; n+=sizeof(size_t))
 		*(size_t *)(tmp.c+n) = *(size_t *)(tmp.c+16+n);
 	memcpy(tmp.c,in+16,residue);
 	(*block)(tmp.c,tmp.c,key);

 	for(n=0; n<16; ++n) {
 		unsigned char c = in[n];
 		out[n] = tmp.c[n] ^ ivec[n];
 		ivec[n] = c;
 	}
 	for(residue+=16; n<residue; ++n)
 		out[n] = tmp.c[n] ^ in[n];

 	return len+residue-16;
 }

 size_t CRYPTO_cts128_decrypt(const unsigned char *in, unsigned char *out,
 			size_t len, const void *key,
 			unsigned char ivec[16], cbc128_f cbc)
 {	size_t residue, n;
 	union { size_t align; unsigned char c[32]; } tmp;

 	assert (in && out && key && ivec);

 	if (len<=16) return 0;

 	if ((residue=len%16) == 0) residue = 16;

 	len -= 16+residue;

 	if (len) {
 		(*cbc)(in,out,len,key,ivec,0);
 		in  += len;
 		out += len;
 	}

 	for (n=16; n<32; n+=sizeof(size_t))
 		*(size_t *)(tmp.c+n) = 0;
 	/* this places in[16] at &tmp.c[16] and decrypted block at &tmp.c[0] */
 	(*cbc)(in,tmp.c,16,key,tmp.c+16,0);

 	memcpy(tmp.c,in+16,residue);
 #if defined(CBC_HANDLES_TRUNCATED_IO)
 	(*cbc)(tmp.c,out,16+residue,key,ivec,0);
 #else
 	(*cbc)(tmp.c,tmp.c,32,key,ivec,0);
 	memcpy(out,tmp.c,16+residue);
 #endif
 	return len+residue;
 }

 #if defined(SELFTEST)
 #include <stdio.h>
 #include <openssl/aes.h>

 /* test vectors from RFC 3962 */
 static const unsigned char test_key[16] = "chicken teriyaki";
 static const unsigned char test_input[64] =
 		"I would like the" " General Gau's C"
 		"hicken, please, " "and wonton soup.";
 static const unsigned char test_iv[16] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

 static const unsigned char vector_17[17] =
 {0xc6,0x35,0x35,0x68,0xf2,0xbf,0x8c,0xb4, 0xd8,0xa5,0x80,0x36,0x2d,0xa7,0xff,0x7f,
  0x97};
 static const unsigned char vector_31[31] =
 {0xfc,0x00,0x78,0x3e,0x0e,0xfd,0xb2,0xc1, 0xd4,0x45,0xd4,0xc8,0xef,0xf7,0xed,0x22,
  0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5};
 static const unsigned char vector_32[32] =
 {0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5,0xa8,
  0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84};
 static const unsigned char vector_47[47] =
 {0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84,
  0xb3,0xff,0xfd,0x94,0x0c,0x16,0xa1,0x8c, 0x1b,0x55,0x49,0xd2,0xf8,0x38,0x02,0x9e,
  0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5};
 static const unsigned char vector_48[48] =
 {0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84,
  0x9d,0xad,0x8b,0xbb,0x96,0xc4,0xcd,0xc0, 0x3b,0xc1,0x03,0xe1,0xa1,0x94,0xbb,0xd8,
  0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5,0xa8};
 static const unsigned char vector_64[64] =
 {0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84,
  0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5,0xa8,
  0x48,0x07,0xef,0xe8,0x36,0xee,0x89,0xa5, 0x26,0x73,0x0d,0xbc,0x2f,0x7b,0xc8,0x40,
  0x9d,0xad,0x8b,0xbb,0x96,0xc4,0xcd,0xc0, 0x3b,0xc1,0x03,0xe1,0xa1,0x94,0xbb,0xd8};

 static AES_KEY encks, decks;

 void test_vector(const unsigned char *vector,size_t len)
 {	unsigned char cleartext[64];
 	unsigned char iv[sizeof(test_iv)];
 	unsigned char ciphertext[64];
 	size_t tail;

 	printf("vector_%d\n",len); fflush(stdout);

 	if ((tail=len%16) == 0) tail = 16;
 	tail += 16;

 	/* test block-based encryption */
 	memcpy(iv,test_iv,sizeof(test_iv));
 	CRYPTO_cts128_encrypt_block(test_input,ciphertext,len,&encks,iv,(block128_f)AES_encrypt);
 	if (memcmp(ciphertext,vector,len))
 		fprintf(stderr,"output_%d mismatch\n",len), exit(1);
 	if (memcmp(iv,vector+len-tail,sizeof(iv)))
 		fprintf(stderr,"iv_%d mismatch\n",len), exit(1);

 	/* test block-based decryption */
 	memcpy(iv,test_iv,sizeof(test_iv));
 	CRYPTO_cts128_decrypt_block(ciphertext,cleartext,len,&decks,iv,(block128_f)AES_decrypt);
 	if (memcmp(cleartext,test_input,len))
 		fprintf(stderr,"input_%d mismatch\n",len), exit(2);
 	if (memcmp(iv,vector+len-tail,sizeof(iv)))
 		fprintf(stderr,"iv_%d mismatch\n",len), exit(2);

 	/* test streamed encryption */
 	memcpy(iv,test_iv,sizeof(test_iv));
 	CRYPTO_cts128_encrypt(test_input,ciphertext,len,&encks,iv,(cbc128_f)AES_cbc_encrypt);
 	if (memcmp(ciphertext,vector,len))
 		fprintf(stderr,"output_%d mismatch\n",len), exit(3);
 	if (memcmp(iv,vector+len-tail,sizeof(iv)))
 		fprintf(stderr,"iv_%d mismatch\n",len), exit(3);

 	/* test streamed decryption */
 	memcpy(iv,test_iv,sizeof(test_iv));
 	CRYPTO_cts128_decrypt(ciphertext,cleartext,len,&decks,iv,(cbc128_f)AES_cbc_encrypt);
 	if (memcmp(cleartext,test_input,len))
 		fprintf(stderr,"input_%d mismatch\n",len), exit(4);
 	if (memcmp(iv,vector+len-tail,sizeof(iv)))
 		fprintf(stderr,"iv_%d mismatch\n",len), exit(4);
 }

 main()
 {
 	AES_set_encrypt_key(test_key,128,&encks);
 	AES_set_decrypt_key(test_key,128,&decks);

 	test_vector(vector_17,sizeof(vector_17));
 	test_vector(vector_31,sizeof(vector_31));
 	test_vector(vector_32,sizeof(vector_32));
 	test_vector(vector_47,sizeof(vector_47));
 	test_vector(vector_48,sizeof(vector_48));
 	test_vector(vector_64,sizeof(vector_64));
 	exit(0);
 }
 #endif
	/* ====================================================================
	* Copyright (c) 2008 The OpenSSL Project. All rights reserved.
	*
	* Rights for redistribution and usage in source and binary
	* forms are granted according to the OpenSSL license.
	*/

	#include "modes.h"
	#include <string.h>

	#ifndef MODES_DEBUG
	# ifndef NDEBUG
	# define NDEBUG
	# endif
	#endif
	#include <assert.h>

	/*
	* Trouble with Ciphertext Stealing, CTS, mode is that there is no
	* common official specification, but couple of cipher/application
	* specific ones: RFC2040 and RFC3962. Then there is 'Proposal to
	* Extend CBC Mode By "Ciphertext Stealing"' at NIST site, which
	* deviates from mentioned RFCs. Most notably it allows input to be
	* of block length and it doesn't flip the order of the last two
	* blocks. CTS is being discussed even in ECB context, but it's not
	* adopted for any known application. This implementation complies
	* with mentioned RFCs and [as such] extends CBC mode.
	*/

	size_t CRYPTO_cts128_encrypt_block(const unsigned char in, unsigned char out,
	size_t len, const void *key,
	unsigned char ivec[16], block128_f block)
	{ size_t residue, n;

	assert (in && out && key && ivec);

	if (len <= 16) return 0;

	if ((residue=len%16) == 0) residue = 16;

	len -= residue;

	CRYPTO_cbc128_encrypt(in,out,len,key,ivec,block);

	in += len;
	out += len;

	for (n=0; n<residue; ++n)
	ivec[n] ^= in[n];
	(*block)(ivec,ivec,key);
	memcpy(out,out-16,residue);
	memcpy(out-16,ivec,16);

	return len+residue;
	}

	size_t CRYPTO_cts128_encrypt(const unsigned char in, unsigned char out,
	size_t len, const void *key,
	unsigned char ivec[16], cbc128_f cbc)
	{ size_t residue;
	union { size_t align; unsigned char c[16]; } tmp;

	assert (in && out && key && ivec);

	if (len <= 16) return 0;

	if ((residue=len%16) == 0) residue = 16;

	len -= residue;

	(*cbc)(in,out,len,key,ivec,1);

	in += len;
	out += len;

	#if defined(CBC_HANDLES_TRUNCATED_IO)
	memcpy(tmp.c,out-16,16);
	(*cbc)(in,out-16,residue,key,ivec,1);
	memcpy(out,tmp.c,residue);
	#else
	{
	size_t n;
	for (n=0; n<16; n+=sizeof(size_t))
	(size_t )(tmp.c+n) = 0;
	memcpy(tmp.c,in,residue);
	}
	memcpy(out,out-16,residue);
	(*cbc)(tmp.c,out-16,16,key,ivec,1);
	#endif
	return len+residue;
	}

	size_t CRYPTO_cts128_decrypt_block(const unsigned char in, unsigned char out,
	size_t len, const void *key,
	unsigned char ivec[16], block128_f block)
	{ size_t residue, n;
	union { size_t align; unsigned char c[32]; } tmp;

	assert (in && out && key && ivec);

	if (len<=16) return 0;

	if ((residue=len%16) == 0) residue = 16;

	len -= 16+residue;

	if (len) {
	CRYPTO_cbc128_decrypt(in,out,len,key,ivec,block);
	in += len;
	out += len;
	}

	(*block)(in,tmp.c+16,key);

	for (n=0; n<16; n+=sizeof(size_t))
	(size_t )(tmp.c+n) = (size_t )(tmp.c+16+n);
	memcpy(tmp.c,in+16,residue);
	(*block)(tmp.c,tmp.c,key);

	for(n=0; n<16; ++n) {
	unsigned char c = in[n];
	out[n] = tmp.c[n] ^ ivec[n];
	ivec[n] = c;
	}
	for(residue+=16; n<residue; ++n)
	out[n] = tmp.c[n] ^ in[n];

	return len+residue-16;
	}

	size_t CRYPTO_cts128_decrypt(const unsigned char in, unsigned char out,
	size_t len, const void *key,
	unsigned char ivec[16], cbc128_f cbc)
	{ size_t residue, n;
	union { size_t align; unsigned char c[32]; } tmp;

	assert (in && out && key && ivec);

	if (len<=16) return 0;

	if ((residue=len%16) == 0) residue = 16;

	len -= 16+residue;

	if (len) {
	(*cbc)(in,out,len,key,ivec,0);
	in += len;
	out += len;
	}

	for (n=16; n<32; n+=sizeof(size_t))
	(size_t )(tmp.c+n) = 0;
	/* this places in[16] at &tmp.c[16] and decrypted block at &tmp.c[0] */
	(*cbc)(in,tmp.c,16,key,tmp.c+16,0);

	memcpy(tmp.c,in+16,residue);
	#if defined(CBC_HANDLES_TRUNCATED_IO)
	(*cbc)(tmp.c,out,16+residue,key,ivec,0);
	#else
	(*cbc)(tmp.c,tmp.c,32,key,ivec,0);
	memcpy(out,tmp.c,16+residue);
	#endif
	return len+residue;
	}

	#if defined(SELFTEST)
	#include <stdio.h>
	#include <openssl/aes.h>

	/* test vectors from RFC 3962 */
	static const unsigned char test_key[16] = "chicken teriyaki";
	static const unsigned char test_input[64] =
	"I would like the" " General Gau's C"
	"hicken, please, " "and wonton soup.";
	static const unsigned char test_iv[16] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

	static const unsigned char vector_17[17] =
	{0xc6,0x35,0x35,0x68,0xf2,0xbf,0x8c,0xb4, 0xd8,0xa5,0x80,0x36,0x2d,0xa7,0xff,0x7f,
	0x97};
	static const unsigned char vector_31[31] =
	{0xfc,0x00,0x78,0x3e,0x0e,0xfd,0xb2,0xc1, 0xd4,0x45,0xd4,0xc8,0xef,0xf7,0xed,0x22,
	0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5};
	static const unsigned char vector_32[32] =
	{0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5,0xa8,
	0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84};
	static const unsigned char vector_47[47] =
	{0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84,
	0xb3,0xff,0xfd,0x94,0x0c,0x16,0xa1,0x8c, 0x1b,0x55,0x49,0xd2,0xf8,0x38,0x02,0x9e,
	0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5};
	static const unsigned char vector_48[48] =
	{0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84,
	0x9d,0xad,0x8b,0xbb,0x96,0xc4,0xcd,0xc0, 0x3b,0xc1,0x03,0xe1,0xa1,0x94,0xbb,0xd8,
	0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5,0xa8};
	static const unsigned char vector_64[64] =
	{0x97,0x68,0x72,0x68,0xd6,0xec,0xcc,0xc0, 0xc0,0x7b,0x25,0xe2,0x5e,0xcf,0xe5,0x84,
	0x39,0x31,0x25,0x23,0xa7,0x86,0x62,0xd5, 0xbe,0x7f,0xcb,0xcc,0x98,0xeb,0xf5,0xa8,
	0x48,0x07,0xef,0xe8,0x36,0xee,0x89,0xa5, 0x26,0x73,0x0d,0xbc,0x2f,0x7b,0xc8,0x40,
	0x9d,0xad,0x8b,0xbb,0x96,0xc4,0xcd,0xc0, 0x3b,0xc1,0x03,0xe1,0xa1,0x94,0xbb,0xd8};

	static AES_KEY encks, decks;

	void test_vector(const unsigned char *vector,size_t len)
	{ unsigned char cleartext[64];
	unsigned char iv[sizeof(test_iv)];
	unsigned char ciphertext[64];
	size_t tail;

	printf("vector_%d\n",len); fflush(stdout);

	if ((tail=len%16) == 0) tail = 16;
	tail += 16;

	/* test block-based encryption */
	memcpy(iv,test_iv,sizeof(test_iv));
	CRYPTO_cts128_encrypt_block(test_input,ciphertext,len,&encks,iv,(block128_f)AES_encrypt);
	if (memcmp(ciphertext,vector,len))
	fprintf(stderr,"output_%d mismatch\n",len), exit(1);
	if (memcmp(iv,vector+len-tail,sizeof(iv)))
	fprintf(stderr,"iv_%d mismatch\n",len), exit(1);

	/* test block-based decryption */
	memcpy(iv,test_iv,sizeof(test_iv));
	CRYPTO_cts128_decrypt_block(ciphertext,cleartext,len,&decks,iv,(block128_f)AES_decrypt);
	if (memcmp(cleartext,test_input,len))
	fprintf(stderr,"input_%d mismatch\n",len), exit(2);
	if (memcmp(iv,vector+len-tail,sizeof(iv)))
	fprintf(stderr,"iv_%d mismatch\n",len), exit(2);

	/* test streamed encryption */
	memcpy(iv,test_iv,sizeof(test_iv));
	CRYPTO_cts128_encrypt(test_input,ciphertext,len,&encks,iv,(cbc128_f)AES_cbc_encrypt);
	if (memcmp(ciphertext,vector,len))
	fprintf(stderr,"output_%d mismatch\n",len), exit(3);
	if (memcmp(iv,vector+len-tail,sizeof(iv)))
	fprintf(stderr,"iv_%d mismatch\n",len), exit(3);

	/* test streamed decryption */
	memcpy(iv,test_iv,sizeof(test_iv));
	CRYPTO_cts128_decrypt(ciphertext,cleartext,len,&decks,iv,(cbc128_f)AES_cbc_encrypt);
	if (memcmp(cleartext,test_input,len))
	fprintf(stderr,"input_%d mismatch\n",len), exit(4);
	if (memcmp(iv,vector+len-tail,sizeof(iv)))
	fprintf(stderr,"iv_%d mismatch\n",len), exit(4);
	}

	main()
	{
	AES_set_encrypt_key(test_key,128,&encks);
	AES_set_decrypt_key(test_key,128,&decks);

	test_vector(vector_17,sizeof(vector_17));
	test_vector(vector_31,sizeof(vector_31));
	test_vector(vector_32,sizeof(vector_32));
	test_vector(vector_47,sizeof(vector_47));
	test_vector(vector_48,sizeof(vector_48));
	test_vector(vector_64,sizeof(vector_64));
	exit(0);
	}
	#endif