| /* |
| Copyright (C) 2006, 2009 by Werner Dittmann |
| |
| This library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| This library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with this library; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| |
| * In addition, as a special exception, the copyright holders give |
| * permission to link the code of portions of this program with the |
| * OpenSSL library under certain conditions as described in each |
| * individual source file, and distribute linked combinations |
| * including the two. |
| * You must obey the GNU General Public License in all respects |
| * for all of the code used other than OpenSSL. If you modify |
| * file(s) with this exception, you may extend this exception to your |
| * version of the file(s), but you are not obligated to do so. If you |
| * do not wish to do so, delete this exception statement from your |
| * version. If you delete this exception statement from all source |
| * files in the program, then also delete it here. |
| */ |
| |
| /** Copyright (C) 2006, 2009 |
| * |
| * @author Werner Dittmann <Werner.Dittmann@t-online.de> |
| */ |
| |
| #include <string.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| |
| #include <bn.h> |
| #include <bnprint.h> |
| #include <ec/ec.h> |
| #include <ec/ecdh.h> |
| #include <zrtp/crypto/zrtpDH.h> |
| #include <zrtp/libzrtpcpp/ZrtpTextData.h> |
| #include <cryptcommon/aes.h> |
| #include <cryptcommon/ZrtpRandom.h> |
| |
| |
| static BigNum bnP2048 = {0}; |
| static BigNum bnP3072 = {0}; |
| |
| static BigNum bnP2048MinusOne = {0}; |
| static BigNum bnP3072MinusOne = {0}; |
| |
| static BigNum two = {0}; |
| |
| static uint8_t dhinit = 0; |
| |
| typedef struct _dhCtx { |
| BigNum privKey; |
| BigNum pubKey; |
| EcCurve curve; |
| EcPoint pubPoint; |
| } dhCtx; |
| |
| void randomZRTP(uint8_t *buf, int32_t length) |
| { |
| ZrtpRandom::getRandomData(buf, length); |
| } |
| |
| static const uint8_t P2048[] = |
| { |
| 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xC9, 0x0F, 0xDA, 0xA2, |
| 0x21, 0x68, 0xC2, 0x34, 0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1, |
| 0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 0x02, 0x0B, 0xBE, 0xA6, |
| 0x3B, 0x13, 0x9B, 0x22, 0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD, |
| 0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 0x30, 0x2B, 0x0A, 0x6D, |
| 0xF2, 0x5F, 0x14, 0x37, 0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45, |
| 0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 0xF4, 0x4C, 0x42, 0xE9, |
| 0xA6, 0x37, 0xED, 0x6B, 0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED, |
| 0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 0xAE, 0x9F, 0x24, 0x11, |
| 0x7C, 0x4B, 0x1F, 0xE6, 0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D, |
| 0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 0x98, 0xDA, 0x48, 0x36, |
| 0x1C, 0x55, 0xD3, 0x9A, 0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F, |
| 0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 0x1C, 0x62, 0xF3, 0x56, |
| 0x20, 0x85, 0x52, 0xBB, 0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D, |
| 0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 0xF1, 0x74, 0x6C, 0x08, |
| 0xCA, 0x18, 0x21, 0x7C, 0x32, 0x90, 0x5E, 0x46, 0x2E, 0x36, 0xCE, 0x3B, |
| 0xE3, 0x9E, 0x77, 0x2C, 0x18, 0x0E, 0x86, 0x03, 0x9B, 0x27, 0x83, 0xA2, |
| 0xEC, 0x07, 0xA2, 0x8F, 0xB5, 0xC5, 0x5D, 0xF0, 0x6F, 0x4C, 0x52, 0xC9, |
| 0xDE, 0x2B, 0xCB, 0xF6, 0x95, 0x58, 0x17, 0x18, 0x39, 0x95, 0x49, 0x7C, |
| 0xEA, 0x95, 0x6A, 0xE5, 0x15, 0xD2, 0x26, 0x18, 0x98, 0xFA, 0x05, 0x10, |
| 0x15, 0x72, 0x8E, 0x5A, 0x8A, 0xAC, 0xAA, 0x68, 0xFF, 0xFF, 0xFF, 0xFF, |
| 0xFF, 0xFF, 0xFF, 0xFF |
| }; |
| |
| static const uint8_t P3072[] = |
| { |
| 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xC9, 0x0F, 0xDA, 0xA2, |
| 0x21, 0x68, 0xC2, 0x34, 0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1, |
| 0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 0x02, 0x0B, 0xBE, 0xA6, |
| 0x3B, 0x13, 0x9B, 0x22, 0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD, |
| 0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 0x30, 0x2B, 0x0A, 0x6D, |
| 0xF2, 0x5F, 0x14, 0x37, 0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45, |
| 0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 0xF4, 0x4C, 0x42, 0xE9, |
| 0xA6, 0x37, 0xED, 0x6B, 0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED, |
| 0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 0xAE, 0x9F, 0x24, 0x11, |
| 0x7C, 0x4B, 0x1F, 0xE6, 0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D, |
| 0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 0x98, 0xDA, 0x48, 0x36, |
| 0x1C, 0x55, 0xD3, 0x9A, 0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F, |
| 0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 0x1C, 0x62, 0xF3, 0x56, |
| 0x20, 0x85, 0x52, 0xBB, 0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D, |
| 0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 0xF1, 0x74, 0x6C, 0x08, |
| 0xCA, 0x18, 0x21, 0x7C, 0x32, 0x90, 0x5E, 0x46, 0x2E, 0x36, 0xCE, 0x3B, |
| 0xE3, 0x9E, 0x77, 0x2C, 0x18, 0x0E, 0x86, 0x03, 0x9B, 0x27, 0x83, 0xA2, |
| 0xEC, 0x07, 0xA2, 0x8F, 0xB5, 0xC5, 0x5D, 0xF0, 0x6F, 0x4C, 0x52, 0xC9, |
| 0xDE, 0x2B, 0xCB, 0xF6, 0x95, 0x58, 0x17, 0x18, 0x39, 0x95, 0x49, 0x7C, |
| 0xEA, 0x95, 0x6A, 0xE5, 0x15, 0xD2, 0x26, 0x18, 0x98, 0xFA, 0x05, 0x10, |
| 0x15, 0x72, 0x8E, 0x5A, 0x8A, 0xAA, 0xC4, 0x2D, 0xAD, 0x33, 0x17, 0x0D, |
| 0x04, 0x50, 0x7A, 0x33, 0xA8, 0x55, 0x21, 0xAB, 0xDF, 0x1C, 0xBA, 0x64, |
| 0xEC, 0xFB, 0x85, 0x04, 0x58, 0xDB, 0xEF, 0x0A, 0x8A, 0xEA, 0x71, 0x57, |
| 0x5D, 0x06, 0x0C, 0x7D, 0xB3, 0x97, 0x0F, 0x85, 0xA6, 0xE1, 0xE4, 0xC7, |
| 0xAB, 0xF5, 0xAE, 0x8C, 0xDB, 0x09, 0x33, 0xD7, 0x1E, 0x8C, 0x94, 0xE0, |
| 0x4A, 0x25, 0x61, 0x9D, 0xCE, 0xE3, 0xD2, 0x26, 0x1A, 0xD2, 0xEE, 0x6B, |
| 0xF1, 0x2F, 0xFA, 0x06, 0xD9, 0x8A, 0x08, 0x64, 0xD8, 0x76, 0x02, 0x73, |
| 0x3E, 0xC8, 0x6A, 0x64, 0x52, 0x1F, 0x2B, 0x18, 0x17, 0x7B, 0x20, 0x0C, |
| 0xBB, 0xE1, 0x17, 0x57, 0x7A, 0x61, 0x5D, 0x6C, 0x77, 0x09, 0x88, 0xC0, |
| 0xBA, 0xD9, 0x46, 0xE2, 0x08, 0xE2, 0x4F, 0xA0, 0x74, 0xE5, 0xAB, 0x31, |
| 0x43, 0xDB, 0x5B, 0xFC, 0xE0, 0xFD, 0x10, 0x8E, 0x4B, 0x82, 0xD1, 0x20, |
| 0xA9, 0x3A, 0xD2, 0xCA, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF |
| }; |
| |
| /* ************** |
| static const uint8_t P4096[] = |
| { |
| 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xC9, 0x0F, 0xDA, 0xA2, |
| 0x21, 0x68, 0xC2, 0x34, 0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1, |
| 0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 0x02, 0x0B, 0xBE, 0xA6, |
| 0x3B, 0x13, 0x9B, 0x22, 0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD, |
| 0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 0x30, 0x2B, 0x0A, 0x6D, |
| 0xF2, 0x5F, 0x14, 0x37, 0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45, |
| 0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 0xF4, 0x4C, 0x42, 0xE9, |
| 0xA6, 0x37, 0xED, 0x6B, 0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED, |
| 0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 0xAE, 0x9F, 0x24, 0x11, |
| 0x7C, 0x4B, 0x1F, 0xE6, 0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D, |
| 0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 0x98, 0xDA, 0x48, 0x36, |
| 0x1C, 0x55, 0xD3, 0x9A, 0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F, |
| 0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 0x1C, 0x62, 0xF3, 0x56, |
| 0x20, 0x85, 0x52, 0xBB, 0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D, |
| 0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 0xF1, 0x74, 0x6C, 0x08, |
| 0xCA, 0x18, 0x21, 0x7C, 0x32, 0x90, 0x5E, 0x46, 0x2E, 0x36, 0xCE, 0x3B, |
| 0xE3, 0x9E, 0x77, 0x2C, 0x18, 0x0E, 0x86, 0x03, 0x9B, 0x27, 0x83, 0xA2, |
| 0xEC, 0x07, 0xA2, 0x8F, 0xB5, 0xC5, 0x5D, 0xF0, 0x6F, 0x4C, 0x52, 0xC9, |
| 0xDE, 0x2B, 0xCB, 0xF6, 0x95, 0x58, 0x17, 0x18, 0x39, 0x95, 0x49, 0x7C, |
| 0xEA, 0x95, 0x6A, 0xE5, 0x15, 0xD2, 0x26, 0x18, 0x98, 0xFA, 0x05, 0x10, |
| 0x15, 0x72, 0x8E, 0x5A, 0x8A, 0xAA, 0xC4, 0x2D, 0xAD, 0x33, 0x17, 0x0D, |
| 0x04, 0x50, 0x7A, 0x33, 0xA8, 0x55, 0x21, 0xAB, 0xDF, 0x1C, 0xBA, 0x64, |
| 0xEC, 0xFB, 0x85, 0x04, 0x58, 0xDB, 0xEF, 0x0A, 0x8A, 0xEA, 0x71, 0x57, |
| 0x5D, 0x06, 0x0C, 0x7D, 0xB3, 0x97, 0x0F, 0x85, 0xA6, 0xE1, 0xE4, 0xC7, |
| 0xAB, 0xF5, 0xAE, 0x8C, 0xDB, 0x09, 0x33, 0xD7, 0x1E, 0x8C, 0x94, 0xE0, |
| 0x4A, 0x25, 0x61, 0x9D, 0xCE, 0xE3, 0xD2, 0x26, 0x1A, 0xD2, 0xEE, 0x6B, |
| 0xF1, 0x2F, 0xFA, 0x06, 0xD9, 0x8A, 0x08, 0x64, 0xD8, 0x76, 0x02, 0x73, |
| 0x3E, 0xC8, 0x6A, 0x64, 0x52, 0x1F, 0x2B, 0x18, 0x17, 0x7B, 0x20, 0x0C, |
| 0xBB, 0xE1, 0x17, 0x57, 0x7A, 0x61, 0x5D, 0x6C, 0x77, 0x09, 0x88, 0xC0, |
| 0xBA, 0xD9, 0x46, 0xE2, 0x08, 0xE2, 0x4F, 0xA0, 0x74, 0xE5, 0xAB, 0x31, |
| 0x43, 0xDB, 0x5B, 0xFC, 0xE0, 0xFD, 0x10, 0x8E, 0x4B, 0x82, 0xD1, 0x20, |
| 0xA9, 0x21, 0x08, 0x01, 0x1A, 0x72, 0x3C, 0x12, 0xA7, 0x87, 0xE6, 0xD7, |
| 0x88, 0x71, 0x9A, 0x10, 0xBD, 0xBA, 0x5B, 0x26, 0x99, 0xC3, 0x27, 0x18, |
| 0x6A, 0xF4, 0xE2, 0x3C, 0x1A, 0x94, 0x68, 0x34, 0xB6, 0x15, 0x0B, 0xDA, |
| 0x25, 0x83, 0xE9, 0xCA, 0x2A, 0xD4, 0x4C, 0xE8, 0xDB, 0xBB, 0xC2, 0xDB, |
| 0x04, 0xDE, 0x8E, 0xF9, 0x2E, 0x8E, 0xFC, 0x14, 0x1F, 0xBE, 0xCA, 0xA6, |
| 0x28, 0x7C, 0x59, 0x47, 0x4E, 0x6B, 0xC0, 0x5D, 0x99, 0xB2, 0x96, 0x4F, |
| 0xA0, 0x90, 0xC3, 0xA2, 0x23, 0x3B, 0xA1, 0x86, 0x51, 0x5B, 0xE7, 0xED, |
| 0x1F, 0x61, 0x29, 0x70, 0xCE, 0xE2, 0xD7, 0xAF, 0xB8, 0x1B, 0xDD, 0x76, |
| 0x21, 0x70, 0x48, 0x1C, 0xD0, 0x06, 0x91, 0x27, 0xD5, 0xB0, 0x5A, 0xA9, |
| 0x93, 0xB4, 0xEA, 0x98, 0x8D, 0x8F, 0xDD, 0xC1, 0x86, 0xFF, 0xB7, 0xDC, |
| 0x90, 0xA6, 0xC0, 0x8F, 0x4D, 0xF4, 0x35, 0xC9, 0x34, 0x06, 0x31, 0x99, |
| 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF |
| }; |
| *************** */ |
| |
| ZrtpDH::ZrtpDH(const char* type) { |
| |
| uint8_t random[64]; |
| |
| ctx = static_cast<void*>(new dhCtx); |
| dhCtx* tmpCtx = static_cast<dhCtx*>(ctx); |
| |
| // Well - the algo type is only 4 char thus cast to int32 and compare |
| if (*(int32_t*)type == *(int32_t*)dh2k) { |
| pkType = DH2K; |
| } |
| else if (*(int32_t*)type == *(int32_t*)dh3k) { |
| pkType = DH3K; |
| } |
| else if (*(int32_t*)type == *(int32_t*)ec25) { |
| pkType = EC25; |
| } |
| else if (*(int32_t*)type == *(int32_t*)ec38) { |
| pkType = EC38; |
| } |
| else if (*(int32_t*)type == *(int32_t*)e255) { |
| pkType = E255; |
| } |
| else if (*(int32_t*)type == *(int32_t*)e414) { |
| pkType = E414; |
| } |
| else { |
| return; |
| } |
| |
| randomZRTP(random, sizeof(random)); |
| |
| if (!dhinit) { |
| bnBegin(&two); |
| bnSetQ(&two, 2); |
| |
| bnBegin(&bnP2048); |
| bnInsertBigBytes(&bnP2048, P2048, 0, sizeof(P2048)); |
| bnBegin(&bnP3072); |
| bnInsertBigBytes(&bnP3072, P3072, 0, sizeof(P3072)); |
| |
| bnBegin(&bnP2048MinusOne); |
| bnCopy(&bnP2048MinusOne, &bnP2048); |
| bnSubQ(&bnP2048MinusOne, 1); |
| |
| bnBegin(&bnP3072MinusOne); |
| bnCopy(&bnP3072MinusOne, &bnP3072); |
| bnSubQ(&bnP3072MinusOne, 1); |
| |
| dhinit = 1; |
| } |
| |
| bnBegin(&tmpCtx->privKey); |
| INIT_EC_POINT(&tmpCtx->pubPoint); |
| |
| switch (pkType) { |
| case DH2K: |
| case DH3K: |
| bnInsertBigBytes(&tmpCtx->privKey, random, 0, 256/8); |
| break; |
| |
| case EC25: |
| ecGetCurveNistECp(NIST256P, &tmpCtx->curve); |
| ecGenerateRandomNumber(&tmpCtx->curve, &tmpCtx->privKey); |
| break; |
| |
| case EC38: |
| ecGetCurveNistECp(NIST384P, &tmpCtx->curve); |
| ecGenerateRandomNumber(&tmpCtx->curve, &tmpCtx->privKey); |
| break; |
| |
| case E255: |
| ecGetCurvesCurve(Curve25519, &tmpCtx->curve); |
| ecGenerateRandomNumber(&tmpCtx->curve, &tmpCtx->privKey); |
| break; |
| |
| case E414: |
| ecGetCurvesCurve(Curve3617, &tmpCtx->curve); |
| ecGenerateRandomNumber(&tmpCtx->curve, &tmpCtx->privKey); |
| break; |
| } |
| } |
| |
| ZrtpDH::~ZrtpDH() { |
| if (ctx == NULL) |
| return; |
| |
| dhCtx* tmpCtx = static_cast<dhCtx*>(ctx); |
| FREE_EC_POINT(&tmpCtx->pubPoint); |
| bnEnd(&tmpCtx->privKey); |
| |
| switch (pkType) { |
| case DH2K: |
| case DH3K: |
| bnEnd(&tmpCtx->pubKey); |
| break; |
| |
| case EC25: |
| case EC38: |
| ecFreeCurveNistECp(&tmpCtx->curve); |
| break; |
| |
| case E255: |
| case E414: |
| ecFreeCurvesCurve(&tmpCtx->curve); |
| break; |
| } |
| } |
| |
| int32_t ZrtpDH::computeSecretKey(uint8_t *pubKeyBytes, uint8_t *secret) { |
| |
| dhCtx* tmpCtx = static_cast<dhCtx*>(ctx); |
| |
| int32_t length = getDhSize(); |
| |
| BigNum sec; |
| if (pkType == DH2K || pkType == DH3K) { |
| BigNum pubKeyOther; |
| bnBegin(&pubKeyOther); |
| bnBegin(&sec); |
| |
| bnInsertBigBytes(&pubKeyOther, pubKeyBytes, 0, length); |
| |
| if (pkType == DH2K) { |
| bnExpMod(&sec, &pubKeyOther, &tmpCtx->privKey, &bnP2048); |
| } |
| else if (pkType == DH3K) { |
| bnExpMod(&sec, &pubKeyOther, &tmpCtx->privKey, &bnP3072); |
| } |
| else { |
| return 0; |
| } |
| bnEnd(&pubKeyOther); |
| bnExtractBigBytes(&sec, secret, 0, length); |
| bnEnd(&sec); |
| |
| return length; |
| } |
| |
| if (pkType == EC25 || pkType == EC38 || pkType == E414) { |
| int32_t len = getPubKeySize() / 2; |
| EcPoint pub; |
| |
| bnBegin(&sec); |
| INIT_EC_POINT(&pub); |
| bnSetQ(pub.z, 1); // initialze Z to one, these are affine coords |
| |
| bnInsertBigBytes(pub.x, pubKeyBytes, 0, len); |
| bnInsertBigBytes(pub.y, pubKeyBytes+len, 0, len); |
| |
| /* Generate agreement for responder: sec = pub * privKey */ |
| ecdhComputeAgreement(&tmpCtx->curve, &sec, &pub, &tmpCtx->privKey); |
| bnExtractBigBytes(&sec, secret, 0, length); |
| bnEnd(&sec); |
| FREE_EC_POINT(&pub); |
| |
| return length; |
| } |
| if (pkType == E255) { |
| int32_t len = getPubKeySize(); |
| EcPoint pub; |
| |
| bnBegin(&sec); |
| INIT_EC_POINT(&pub); |
| |
| bnInsertLittleBytes(pub.x, pubKeyBytes, 0, len); |
| |
| /* Generate agreement for responder: sec = pub * privKey */ |
| ecdhComputeAgreement(&tmpCtx->curve, &sec, &pub, &tmpCtx->privKey); |
| bnExtractLittleBytes(&sec, secret, 0, length); |
| bnEnd(&sec); |
| FREE_EC_POINT(&pub); |
| |
| return length; |
| } |
| return -1; |
| } |
| |
| int32_t ZrtpDH::generatePublicKey() |
| { |
| dhCtx* tmpCtx = static_cast<dhCtx*>(ctx); |
| |
| bnBegin(&tmpCtx->pubKey); |
| switch (pkType) { |
| case DH2K: |
| bnExpMod(&tmpCtx->pubKey, &two, &tmpCtx->privKey, &bnP2048); |
| break; |
| |
| case DH3K: |
| bnExpMod(&tmpCtx->pubKey, &two, &tmpCtx->privKey, &bnP3072); |
| break; |
| |
| case EC25: |
| case EC38: |
| case E255: |
| case E414: |
| while (!ecdhGeneratePublic(&tmpCtx->curve, &tmpCtx->pubPoint, &tmpCtx->privKey)) |
| ecGenerateRandomNumber(&tmpCtx->curve, &tmpCtx->privKey); |
| } |
| return 0; |
| } |
| |
| int32_t ZrtpDH::getDhSize() const |
| { |
| switch (pkType) { |
| case DH2K: |
| return 2048/8; |
| break; |
| case DH3K: |
| return 3072/8; |
| break; |
| |
| case EC25: |
| return 32; |
| break; |
| case EC38: |
| return 48; |
| break; |
| |
| case E255: |
| return 32; |
| break; |
| case E414: |
| return 52; |
| break; |
| } |
| return 0; |
| } |
| |
| int32_t ZrtpDH::getPubKeySize() const |
| { |
| dhCtx* tmpCtx = static_cast<dhCtx*>(ctx); |
| if (pkType == DH2K || pkType == DH3K) |
| return bnBytes(&tmpCtx->pubKey); |
| |
| if (pkType == EC25 || pkType == EC38 || pkType == E414) |
| return bnBytes(tmpCtx->curve.p) * 2; // *2 -> x and y coordinate |
| |
| if (pkType == E255) |
| return bnBytes(tmpCtx->curve.p); |
| return 0; |
| |
| } |
| |
| int32_t ZrtpDH::getPubKeyBytes(uint8_t *buf) const |
| { |
| dhCtx* tmpCtx = static_cast<dhCtx*>(ctx); |
| |
| if (pkType == DH2K || pkType == DH3K) { |
| // get len of pub_key, prepend with zeros to DH size |
| int size = getPubKeySize(); |
| int32_t prepend = getDhSize() - size; |
| if (prepend > 0) { |
| memset(buf, 0, prepend); |
| } |
| bnExtractBigBytes(&tmpCtx->pubKey, buf + prepend, 0, size); |
| return size; |
| } |
| |
| if (pkType == EC25 || pkType == EC38 || pkType == E414) { |
| int32_t len = getPubKeySize() / 2; |
| |
| bnExtractBigBytes(tmpCtx->pubPoint.x, buf, 0, len); |
| bnExtractBigBytes(tmpCtx->pubPoint.y, buf+len, 0, len); |
| return len * 2; |
| } |
| if (pkType == E255) { |
| int32_t len = getPubKeySize(); |
| bnExtractLittleBytes(tmpCtx->pubPoint.x, buf, 0, len); |
| return len; |
| } |
| return 0; |
| } |
| |
| int32_t ZrtpDH::checkPubKey(uint8_t *pubKeyBytes) const |
| { |
| |
| /* ECC validation (partial), NIST SP800-56A, section 5.6.2.6 */ |
| if (pkType == EC25 || pkType == EC38 || pkType == E414) { |
| |
| dhCtx* tmpCtx = static_cast<dhCtx*>(ctx); |
| EcPoint pub; |
| |
| INIT_EC_POINT(&pub); |
| int32_t len = getPubKeySize() / 2; |
| |
| bnInsertBigBytes(pub.x, pubKeyBytes, 0, len); |
| bnInsertBigBytes(pub.y, pubKeyBytes+len, 0, len); |
| |
| return ecCheckPubKey(&tmpCtx->curve, &pub); |
| } |
| |
| if (pkType == E255) { |
| return 1; |
| } |
| |
| BigNum pubKeyOther; |
| bnBegin(&pubKeyOther); |
| bnInsertBigBytes(&pubKeyOther, pubKeyBytes, 0, getDhSize()); |
| |
| if (pkType == DH2K) { |
| if (bnCmp(&bnP2048MinusOne, &pubKeyOther) == 0) { |
| return 0; |
| } |
| } |
| else if (pkType == DH3K) { |
| if (bnCmp(&bnP3072MinusOne, &pubKeyOther) == 0) { |
| return 0; |
| |
| } |
| } |
| else { |
| return 0; |
| } |
| if (bnCmpQ(&pubKeyOther, 1) == 0) { |
| return 0; |
| } |
| |
| bnEnd(&pubKeyOther); |
| return 1; |
| } |
| |
| const char* ZrtpDH::getDHtype() |
| { |
| switch (pkType) { |
| case DH2K: |
| return dh2k; |
| case DH3K: |
| return dh3k; |
| case EC25: |
| return ec25; |
| case EC38: |
| return ec38; |
| case E255: |
| return e255; |
| case E414: |
| return e414; |
| } |
| return NULL; |
| } |
| |
| /** EMACS ** |
| * Local variables: |
| * mode: c++ |
| * c-default-style: ellemtel |
| * c-basic-offset: 4 |
| * End: |
| */ |