Index: openssl/crypto/modes/cts128.c |
=================================================================== |
--- openssl/crypto/modes/cts128.c (revision 0) |
+++ openssl/crypto/modes/cts128.c (revision 0) |
@@ -0,0 +1,259 @@ |
+/* ==================================================================== |
+ * 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 |