| /* ==================================================================== |
| * 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 <openssl/crypto.h> |
| #include "modes_lcl.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 provides |
| * two interfaces: one compliant with above mentioned RFCs and one |
| * compliant with the NIST proposal, both extending 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_nistcts128_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; |
| |
| residue = len % 16; |
| |
| len -= residue; |
| |
| CRYPTO_cbc128_encrypt(in, out, len, key, ivec, block); |
| |
| if (residue == 0) |
| return len; |
| |
| in += len; |
| out += len; |
| |
| for (n = 0; n < residue; ++n) |
| ivec[n] ^= in[n]; |
| (*block) (ivec, ivec, key); |
| memcpy(out - 16 + residue, 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 |
| memset(tmp.c, 0, sizeof(tmp)); |
| 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_nistcts128_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; |
| |
| residue = len % 16; |
| |
| len -= residue; |
| |
| (*cbc) (in, out, len, key, ivec, 1); |
| |
| if (residue == 0) |
| return len; |
| |
| in += len; |
| out += len; |
| |
| #if defined(CBC_HANDLES_TRUNCATED_IO) |
| (*cbc) (in, out - 16 + residue, residue, key, ivec, 1); |
| #else |
| memset(tmp.c, 0, sizeof(tmp)); |
| memcpy(tmp.c, in, residue); |
| (*cbc) (tmp.c, out - 16 + residue, 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); |
| |
| memcpy(tmp.c, tmp.c + 16, 16); |
| 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 16 + len + residue; |
| } |
| |
| size_t CRYPTO_nistcts128_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; |
| |
| residue = len % 16; |
| |
| if (residue == 0) { |
| CRYPTO_cbc128_decrypt(in, out, len, key, ivec, block); |
| return len; |
| } |
| |
| len -= 16 + residue; |
| |
| if (len) { |
| CRYPTO_cbc128_decrypt(in, out, len, key, ivec, block); |
| in += len; |
| out += len; |
| } |
| |
| (*block) (in + residue, tmp.c + 16, key); |
| |
| memcpy(tmp.c, tmp.c + 16, 16); |
| memcpy(tmp.c, in, 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] = in[n + residue]; |
| tmp.c[n] = c; |
| } |
| for (residue += 16; n < residue; ++n) |
| out[n] = tmp.c[n] ^ tmp.c[n - 16]; |
| |
| return 16 + len + residue; |
| } |
| |
| 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; |
| 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; |
| } |
| |
| memset(tmp.c, 0, sizeof(tmp)); |
| /* |
| * 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 16 + len + residue; |
| } |
| |
| size_t CRYPTO_nistcts128_decrypt(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[32]; |
| } tmp; |
| |
| assert(in && out && key && ivec); |
| |
| if (len < 16) |
| return 0; |
| |
| residue = len % 16; |
| |
| if (residue == 0) { |
| (*cbc) (in, out, len, key, ivec, 0); |
| return len; |
| } |
| |
| len -= 16 + residue; |
| |
| if (len) { |
| (*cbc) (in, out, len, key, ivec, 0); |
| in += len; |
| out += len; |
| } |
| |
| memset(tmp.c, 0, sizeof(tmp)); |
| /* |
| * this places in[16] at &tmp.c[16] and decrypted block at &tmp.c[0] |
| */ |
| (*cbc) (in + residue, tmp.c, 16, key, tmp.c + 16, 0); |
| |
| memcpy(tmp.c, in, 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 16 + 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 iv[sizeof(test_iv)]; |
| unsigned char cleartext[64], 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); |
| } |
| |
| void test_nistvector(const unsigned char *vector, size_t len) |
| { |
| unsigned char iv[sizeof(test_iv)]; |
| unsigned char cleartext[64], ciphertext[64], nistvector[64]; |
| size_t tail; |
| |
| printf("nistvector_%d\n", len); |
| fflush(stdout); |
| |
| if ((tail = len % 16) == 0) |
| tail = 16; |
| |
| len -= 16 + tail; |
| memcpy(nistvector, vector, len); |
| /* flip two last blocks */ |
| memcpy(nistvector + len, vector + len + 16, tail); |
| memcpy(nistvector + len + tail, vector + len, 16); |
| len += 16 + tail; |
| tail = 16; |
| |
| /* test block-based encryption */ |
| memcpy(iv, test_iv, sizeof(test_iv)); |
| CRYPTO_nistcts128_encrypt_block(test_input, ciphertext, len, &encks, iv, |
| (block128_f) AES_encrypt); |
| if (memcmp(ciphertext, nistvector, len)) |
| fprintf(stderr, "output_%d mismatch\n", len), exit(1); |
| if (memcmp(iv, nistvector + 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_nistcts128_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, nistvector + len - tail, sizeof(iv))) |
| fprintf(stderr, "iv_%d mismatch\n", len), exit(2); |
| |
| /* test streamed encryption */ |
| memcpy(iv, test_iv, sizeof(test_iv)); |
| CRYPTO_nistcts128_encrypt(test_input, ciphertext, len, &encks, iv, |
| (cbc128_f) AES_cbc_encrypt); |
| if (memcmp(ciphertext, nistvector, len)) |
| fprintf(stderr, "output_%d mismatch\n", len), exit(3); |
| if (memcmp(iv, nistvector + len - tail, sizeof(iv))) |
| fprintf(stderr, "iv_%d mismatch\n", len), exit(3); |
| |
| /* test streamed decryption */ |
| memcpy(iv, test_iv, sizeof(test_iv)); |
| CRYPTO_nistcts128_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, nistvector + len - tail, sizeof(iv))) |
| fprintf(stderr, "iv_%d mismatch\n", len), exit(4); |
| } |
| |
| int 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)); |
| |
| test_nistvector(vector_17, sizeof(vector_17)); |
| test_nistvector(vector_31, sizeof(vector_31)); |
| test_nistvector(vector_32, sizeof(vector_32)); |
| test_nistvector(vector_47, sizeof(vector_47)); |
| test_nistvector(vector_48, sizeof(vector_48)); |
| test_nistvector(vector_64, sizeof(vector_64)); |
| |
| return 0; |
| } |
| #endif |