diff options
Diffstat (limited to 'srtp/tables')
-rw-r--r-- | srtp/tables/.cvsignore | 1 | ||||
-rw-r--r-- | srtp/tables/CVS/Entries | 3 | ||||
-rw-r--r-- | srtp/tables/CVS/Repository | 1 | ||||
-rw-r--r-- | srtp/tables/CVS/Root | 1 | ||||
-rw-r--r-- | srtp/tables/aes_tables.c | 346 |
5 files changed, 352 insertions, 0 deletions
diff --git a/srtp/tables/.cvsignore b/srtp/tables/.cvsignore new file mode 100644 index 0000000..45492b4 --- /dev/null +++ b/srtp/tables/.cvsignore @@ -0,0 +1 @@ +aes_tables diff --git a/srtp/tables/CVS/Entries b/srtp/tables/CVS/Entries new file mode 100644 index 0000000..c0cc166 --- /dev/null +++ b/srtp/tables/CVS/Entries @@ -0,0 +1,3 @@ +/.cvsignore/1.1/Thu Sep 29 12:06:41 2005// +/aes_tables.c/1.7/Thu Jun 8 17:00:29 2006// +D diff --git a/srtp/tables/CVS/Repository b/srtp/tables/CVS/Repository new file mode 100644 index 0000000..9cf6c91 --- /dev/null +++ b/srtp/tables/CVS/Repository @@ -0,0 +1 @@ +srtp/tables diff --git a/srtp/tables/CVS/Root b/srtp/tables/CVS/Root new file mode 100644 index 0000000..05e15d8 --- /dev/null +++ b/srtp/tables/CVS/Root @@ -0,0 +1 @@ +srtp.cvs.sourceforge.net:/cvsroot/srtp diff --git a/srtp/tables/aes_tables.c b/srtp/tables/aes_tables.c new file mode 100644 index 0000000..b2bc1d7 --- /dev/null +++ b/srtp/tables/aes_tables.c @@ -0,0 +1,346 @@ +/* + * aes_tables.c + * + * generate tables for the AES cipher + * + * David A. McGrew + * Cisco Systems, Inc. + */ +/* + * + * Copyright(c) 2001-2006 Cisco Systems, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 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. + * + * Neither the name of the Cisco Systems, Inc. nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "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 + * COPYRIGHT HOLDERS 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. + * + */ + +#include <stdio.h> +#include "gf2_8.h" +#include "crypto_math.h" + + +unsigned char aes_sbox[256]; + +unsigned char aes_inv_sbox[256]; + +uint32_t T0[256], T1[256], T2[256], T3[256], T4[256]; + + +#define AES_INVERSE_TEST 0 /* set to 1 to test forward/backwards aes */ + +/* functions for precomputing AES values */ + +/* + * A[] is the 8 x 8 binary matrix (represented as an array of columns, + * where each column is an octet) which defines the affine + * transformation used in the AES substitution table (Section + * 4.2.1 of the spec). + */ + +uint8_t A[8] = { 31, 62, 124, 248, 241, 227, 199, 143 }; + +/* + * b is the 8 bit vector (represented as an octet) used in the affine + * transform described above. + */ + +uint8_t b = 99; + + +void +aes_init_sbox(void) { + unsigned int i; + uint8_t x; + + for (i=0; i < 256; i++) { + x = gf2_8_compute_inverse((gf2_8)i); + x = A_times_x_plus_b(A, x, b); + aes_sbox[i] = x; + aes_inv_sbox[x] = i; + } +} + +void +aes_compute_tables(void) { + int i; + uint32_t x1, x2, x3; + v32_t tmp; + + /* initialize substitution table */ + aes_init_sbox(); + + /* combine sbox with linear operations to form 8-bit to 32-bit tables */ + for (i=0; i < 256; i++) { + x1 = aes_sbox[i]; + x2 = gf2_8_shift(x1); + x3 = x2 ^ x1; + + tmp.v8[0] = x2; + tmp.v8[1] = x1; + tmp.v8[2] = x1; + tmp.v8[3] = x3; + T0[i] = tmp.value; + + tmp.v8[0] = x3; + tmp.v8[1] = x2; + tmp.v8[2] = x1; + tmp.v8[3] = x1; + T1[i] = tmp.value; + + tmp.v8[0] = x1; + tmp.v8[1] = x3; + tmp.v8[2] = x2; + tmp.v8[3] = x1; + T2[i] = tmp.value; + + tmp.v8[0] = x1; + tmp.v8[1] = x1; + tmp.v8[2] = x3; + tmp.v8[3] = x2; + T3[i] = tmp.value; + + } +} + + +/* + * the tables U0, U1, U2, U3 implement the aes operations invSubBytes, + * invMixColumns, and invShiftRows + */ + +uint32_t U0[256], U1[256], U2[256], U3[256], U4[256]; + +extern uint8_t aes_inv_sbox[256]; + +void +aes_compute_inv_tables(void) { + int i; + uint8_t x, xe, x9, xd, xb; + v32_t tmp; + + /* combine sbox with linear operations to form 8-bit to 32-bit tables */ + for (i=0; i < 256; i++) { + x = aes_inv_sbox[i]; + + xe = gf2_8_multiply(0x0e, x); + x9 = gf2_8_multiply(0x09, x); + xd = gf2_8_multiply(0x0d, x); + xb = gf2_8_multiply(0x0b, x); + + tmp.v8[0] = xe; + tmp.v8[1] = x9; + tmp.v8[2] = xd; + tmp.v8[3] = xb; + U0[i] = tmp.value; + + tmp.v8[0] = xb; + tmp.v8[1] = xe; + tmp.v8[2] = x9; + tmp.v8[3] = xd; + U1[i] = tmp.value; + + tmp.v8[0] = xd; + tmp.v8[1] = xb; + tmp.v8[2] = xe; + tmp.v8[3] = x9; + U2[i] = tmp.value; + + tmp.v8[0] = x9; + tmp.v8[1] = xd; + tmp.v8[2] = xb; + tmp.v8[3] = xe; + U3[i] = tmp.value; + + tmp.v8[0] = tmp.v8[1] = tmp.v8[2] = tmp.v8[3] = x; + U4[i] = tmp.value; + } +} + + +/* + * aes_test_inverse() returns err_status_ok if aes + * encryption and decryption are true inverses of each other, and + * returns err_status_algo_fail otherwise + */ + +#include "err.h" + +err_status_t +aes_test_inverse(void); + +#define TABLES_32BIT 1 + +int +main(void) { + int i; + + aes_init_sbox(); + aes_compute_inv_tables(); + +#if TABLES_32BIT + printf("uint32_t U0 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%0x, ", U0[i]); + } + printf("\n}\n"); + + printf("uint32_t U1 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%x, ", U1[i]); + } + printf("\n}\n"); + + printf("uint32_t U2 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%x, ", U2[i]); + } + printf("\n}\n"); + + printf("uint32_t U3 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%x, ", U3[i]); + } + printf("\n}\n"); + + printf("uint32_t U4 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%x, ", U4[i]); + } + printf("\n}\n"); + +#else + + printf("uint32_t U0 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%lx, ", U0[i]); + } + printf("\n}\n"); + + printf("uint32_t U1 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%lx, ", U1[i]); + } + printf("\n}\n"); + + printf("uint32_t U2 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%lx, ", U2[i]); + } + printf("\n}\n"); + + printf("uint32_t U3 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%lx, ", U3[i]); + } + printf("\n}\n"); + + printf("uint32_t U4 = {"); + for (i=0; i < 256; i++) { + if ((i % 4) == 0) + printf("\n"); + printf("0x%lx, ", U4[i]); + } + printf("\n}\n"); + + +#endif /* TABLES_32BIT */ + + +#if AES_INVERSE_TEST + /* + * test that aes_encrypt and aes_decrypt are actually + * inverses of each other + */ + + printf("aes inverse test: "); + if (aes_test_inverse() == err_status_ok) + printf("passed\n"); + else { + printf("failed\n"); + exit(1); + } +#endif + + return 0; +} + +#if AES_INVERSE_TEST + +err_status_t +aes_test_inverse(void) { + v128_t x, y; + aes_expanded_key_t expanded_key, decrypt_key; + uint8_t plaintext[16] = { + 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, + 0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff + }; + uint8_t key[16] = { + 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, + 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f + }; + v128_t k; + v128_set_to_zero(&x); + + v128_copy_octet_string(&k, key); + v128_copy_octet_string(&x, plaintext); + aes_expand_encryption_key(k, expanded_key); + aes_expand_decryption_key(k, decrypt_key); + aes_encrypt(&x, expanded_key); + aes_decrypt(&x, decrypt_key); + + /* compare to expected value then report */ + v128_copy_octet_string(&y, plaintext); + + if (v128_is_eq(&x, &y)) + return err_status_ok; + return err_status_algo_fail; + +} + +#endif |