/* * COMP128 implementation * * * This code is inspired by original code from : * Marc Briceno , Ian Goldberg , * and David Wagner * * But it has been fully rewritten from various PDFs found online describing * the algorithm because the licence of the code referenced above was unclear. * A comment snippet from the original code is included below, it describes * where the doc came from and how the algorithm was reverse engineered. * * * (C) 2009 by Sylvain Munaut * * All Rights Reserved * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * */ /* * --- SNIP --- * * This code derived from a leaked document from the GSM standards. * Some missing pieces were filled in by reverse-engineering a working SIM. * We have verified that this is the correct COMP128 algorithm. * * The first page of the document identifies it as * _Technical Information: GSM System Security Study_. * 10-1617-01, 10th June 1988. * The bottom of the title page is marked * Racal Research Ltd. * Worton Drive, Worton Grange Industrial Estate, * Reading, Berks. RG2 0SB, England. * Telephone: Reading (0734) 868601 Telex: 847152 * The relevant bits are in Part I, Section 20 (pages 66--67). Enjoy! * * Note: There are three typos in the spec (discovered by * reverse-engineering). * First, "z = (2 * x[n] + x[n]) mod 2^(9-j)" should clearly read * "z = (2 * x[m] + x[n]) mod 2^(9-j)". * Second, the "k" loop in the "Form bits from bytes" section is severely * botched: the k index should run only from 0 to 3, and clearly the range * on "the (8-k)th bit of byte j" is also off (should be 0..7, not 1..8, * to be consistent with the subsequent section). * Third, SRES is taken from the first 8 nibbles of x[], not the last 8 as * claimed in the document. (And the document doesn't specify how Kc is * derived, but that was also easily discovered with reverse engineering.) * All of these typos have been corrected in the following code. * * --- /SNIP --- */ #include #include /* The compression tables (just copied ...) */ static const uint8_t table_0[512] = { 102, 177, 186, 162, 2, 156, 112, 75, 55, 25, 8, 12, 251, 193, 246, 188, 109, 213, 151, 53, 42, 79, 191, 115, 233, 242, 164, 223, 209, 148, 108, 161, 252, 37, 244, 47, 64, 211, 6, 237, 185, 160, 139, 113, 76, 138, 59, 70, 67, 26, 13, 157, 63, 179, 221, 30, 214, 36, 166, 69, 152, 124, 207, 116, 247, 194, 41, 84, 71, 1, 49, 14, 95, 35, 169, 21, 96, 78, 215, 225, 182, 243, 28, 92, 201, 118, 4, 74, 248, 128, 17, 11, 146, 132, 245, 48, 149, 90, 120, 39, 87, 230, 106, 232, 175, 19, 126, 190, 202, 141, 137, 176, 250, 27, 101, 40, 219, 227, 58, 20, 51, 178, 98, 216, 140, 22, 32, 121, 61, 103, 203, 72, 29, 110, 85, 212, 180, 204, 150, 183, 15, 66, 172, 196, 56, 197, 158, 0, 100, 45, 153, 7, 144, 222, 163, 167, 60, 135, 210, 231, 174, 165, 38, 249, 224, 34, 220, 229, 217, 208, 241, 68, 206, 189, 125, 255, 239, 54, 168, 89, 123, 122, 73, 145, 117, 234, 143, 99, 129, 200, 192, 82, 104, 170, 136, 235, 93, 81, 205, 173, 236, 94, 105, 52, 46, 228, 198, 5, 57, 254, 97, 155, 142, 133, 199, 171, 187, 50, 65, 181, 127, 107, 147, 226, 184, 218, 131, 33, 77, 86, 31, 44, 88, 62, 238, 18, 24, 43, 154, 23, 80, 159, 134, 111, 9, 114, 3, 91, 16, 130, 83, 10, 195, 240, 253, 119, 177, 102, 162, 186, 156, 2, 75, 112, 25, 55, 12, 8, 193, 251, 188, 246, 213, 109, 53, 151, 79, 42, 115, 191, 242, 233, 223, 164, 148, 209, 161, 108, 37, 252, 47, 244, 211, 64, 237, 6, 160, 185, 113, 139, 138, 76, 70, 59, 26, 67, 157, 13, 179, 63, 30, 221, 36, 214, 69, 166, 124, 152, 116, 207, 194, 247, 84, 41, 1, 71, 14, 49, 35, 95, 21, 169, 78, 96, 225, 215, 243, 182, 92, 28, 118, 201, 74, 4, 128, 248, 11, 17, 132, 146, 48, 245, 90, 149, 39, 120, 230, 87, 232, 106, 19, 175, 190, 126, 141, 202, 176, 137, 27, 250, 40, 101, 227, 219, 20, 58, 178, 51, 216, 98, 22, 140, 121, 32, 103, 61, 72, 203, 110, 29, 212, 85, 204, 180, 183, 150, 66, 15, 196, 172, 197, 56, 0, 158, 45, 100, 7, 153, 222, 144, 167, 163, 135, 60, 231, 210, 165, 174, 249, 38, 34, 224, 229, 220, 208, 217, 68, 241, 189, 206, 255, 125, 54, 239, 89, 168, 122, 123, 145, 73, 234, 117, 99, 143, 200, 129, 82, 192, 170, 104, 235, 136, 81, 93, 173, 205, 94, 236, 52, 105, 228, 46, 5, 198, 254, 57, 155, 97, 133, 142, 171, 199, 50, 187, 181, 65, 107, 127, 226, 147, 218, 184, 33, 131, 86, 77, 44, 31, 62, 88, 18, 238, 43, 24, 23, 154, 159, 80, 111, 134, 114, 9, 91, 3, 130, 16, 10, 83, 240, 195, 119, 253, }, table_1[256] = { 19, 11, 80, 114, 43, 1, 69, 94, 39, 18, 127, 117, 97, 3, 85, 43, 27, 124, 70, 83, 47, 71, 63, 10, 47, 89, 79, 4, 14, 59, 11, 5, 35, 107, 103, 68, 21, 86, 36, 91, 85, 126, 32, 50, 109, 94, 120, 6, 53, 79, 28, 45, 99, 95, 41, 34, 88, 68, 93, 55, 110, 125, 105, 20, 90, 80, 76, 96, 23, 60, 89, 64, 121, 56, 14, 74, 101, 8, 19, 78, 76, 66, 104, 46, 111, 50, 32, 3, 39, 0, 58, 25, 92, 22, 18, 51, 57, 65, 119, 116, 22, 109, 7, 86, 59, 93, 62, 110, 78, 99, 77, 67, 12, 113, 87, 98, 102, 5, 88, 33, 38, 56, 23, 8, 75, 45, 13, 75, 95, 63, 28, 49, 123, 120, 20, 112, 44, 30, 15, 98, 106, 2, 103, 29, 82, 107, 42, 124, 24, 30, 41, 16, 108, 100, 117, 40, 73, 40, 7, 114, 82, 115, 36, 112, 12, 102, 100, 84, 92, 48, 72, 97, 9, 54, 55, 74, 113, 123, 17, 26, 53, 58, 4, 9, 69, 122, 21, 118, 42, 60, 27, 73, 118, 125, 34, 15, 65, 115, 84, 64, 62, 81, 70, 1, 24, 111, 121, 83, 104, 81, 49, 127, 48, 105, 31, 10, 6, 91, 87, 37, 16, 54, 116, 126, 31, 38, 13, 0, 72, 106, 77, 61, 26, 67, 46, 29, 96, 37, 61, 52, 101, 17, 44, 108, 71, 52, 66, 57, 33, 51, 25, 90, 2, 119, 122, 35, }, table_2[128] = { 52, 50, 44, 6, 21, 49, 41, 59, 39, 51, 25, 32, 51, 47, 52, 43, 37, 4, 40, 34, 61, 12, 28, 4, 58, 23, 8, 15, 12, 22, 9, 18, 55, 10, 33, 35, 50, 1, 43, 3, 57, 13, 62, 14, 7, 42, 44, 59, 62, 57, 27, 6, 8, 31, 26, 54, 41, 22, 45, 20, 39, 3, 16, 56, 48, 2, 21, 28, 36, 42, 60, 33, 34, 18, 0, 11, 24, 10, 17, 61, 29, 14, 45, 26, 55, 46, 11, 17, 54, 46, 9, 24, 30, 60, 32, 0, 20, 38, 2, 30, 58, 35, 1, 16, 56, 40, 23, 48, 13, 19, 19, 27, 31, 53, 47, 38, 63, 15, 49, 5, 37, 53, 25, 36, 63, 29, 5, 7, }, table_3[64] = { 1, 5, 29, 6, 25, 1, 18, 23, 17, 19, 0, 9, 24, 25, 6, 31, 28, 20, 24, 30, 4, 27, 3, 13, 15, 16, 14, 18, 4, 3, 8, 9, 20, 0, 12, 26, 21, 8, 28, 2, 29, 2, 15, 7, 11, 22, 14, 10, 17, 21, 12, 30, 26, 27, 16, 31, 11, 7, 13, 23, 10, 5, 22, 19, }, table_4[32] = { 15, 12, 10, 4, 1, 14, 11, 7, 5, 0, 14, 7, 1, 2, 13, 8, 10, 3, 4, 9, 6, 0, 3, 2, 5, 6, 8, 9, 11, 13, 15, 12, }; static const uint8_t *_comp128_table[5] = { table_0, table_1, table_2, table_3, table_4 }; static inline void _comp128_compression_round(uint8_t *x, int n, const uint8_t *tbl) { int i, j, m, a, b, y, z; m = 4 - n; for (i=0; i<(1<>2] & (1<<(3-(i&3)))) bits[i] = 1; } static inline void _comp128_permutation(uint8_t *x, uint8_t *bits) { int i; memset(&x[16], 0x00, 16); for (i=0; i<128; i++) x[(i>>3)+16] |= bits[(i*17) & 127] << (7-(i&7)); } void comp128(uint8_t *ki, uint8_t *rand, uint8_t *sres, uint8_t *kc) { int i; uint8_t x[32], bits[128]; /* x[16-31] = RAND */ memcpy(&x[16], rand, 16); /* Round 1-7 */ for (i=0; i<7; i++) { /* x[0-15] = Ki */ memcpy(x, ki, 16); /* Compression */ _comp128_compression(x); /* FormBitFromBytes */ _comp128_bitsfrombytes(x, bits); /* Permutation */ _comp128_permutation(x, bits); } /* Round 8 (final) */ /* x[0-15] = Ki */ memcpy(x, ki, 16); /* Compression */ _comp128_compression(x); /* Output stage */ for (i=0; i<8; i+=2) sres[i>>1] = x[i]<<4 | x[i+1]; for (i=0; i<12; i+=2) kc[i>>1] = (x[i + 18] << 6) | (x[i + 19] << 2) | (x[i + 20] >> 2); kc[6] = (x[30]<<6) | (x[31]<<2); kc[7] = 0; }