Use side-channel secured mpz_powm_sec of libgmp 5, if available
[strongswan.git] / src / libstrongswan / plugins / gmp / gmp_diffie_hellman.c
1 /*
2 * Copyright (C) 1998-2002 D. Hugh Redelmeier.
3 * Copyright (C) 1999, 2000, 2001 Henry Spencer.
4 * Copyright (C) 2005-2008 Martin Willi
5 * Copyright (C) 2005 Jan Hutter
6 * Hochschule fuer Technik Rapperswil
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 * for more details.
17 */
18
19 #include <gmp.h>
20
21 #include "gmp_diffie_hellman.h"
22
23 #include <debug.h>
24
25 #ifdef HAVE_MPZ_POWM_SEC
26 # undef mpz_powm
27 # define mpz_powm mpz_powm_sec
28 #endif
29
30 /**
31 * Modulus of Group 1 (MODP_768_BIT).
32 */
33 static u_int8_t group1_modulus[] = {
34 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
35 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
36 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
37 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
38 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
39 0xF4,0x4C,0x42,0xE9,0xA6,0x3A,0x36,0x20,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
40 };
41
42 /**
43 * Modulus of Group 2 (MODP_1024_BIT).
44 */
45 static u_int8_t group2_modulus[] = {
46 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
47 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
48 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
49 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
50 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
51 0xF4,0x4C,0x42,0xE9,0xA6,0x37,0xED,0x6B,0x0B,0xFF,0x5C,0xB6,0xF4,0x06,0xB7,0xED,
52 0xEE,0x38,0x6B,0xFB,0x5A,0x89,0x9F,0xA5,0xAE,0x9F,0x24,0x11,0x7C,0x4B,0x1F,0xE6,
53 0x49,0x28,0x66,0x51,0xEC,0xE6,0x53,0x81,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
54 };
55
56 /**
57 * Modulus of Group 5 (MODP_1536_BIT).
58 */
59 static u_int8_t group5_modulus[] = {
60 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
61 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
62 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
63 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
64 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
65 0xF4,0x4C,0x42,0xE9,0xA6,0x37,0xED,0x6B,0x0B,0xFF,0x5C,0xB6,0xF4,0x06,0xB7,0xED,
66 0xEE,0x38,0x6B,0xFB,0x5A,0x89,0x9F,0xA5,0xAE,0x9F,0x24,0x11,0x7C,0x4B,0x1F,0xE6,
67 0x49,0x28,0x66,0x51,0xEC,0xE4,0x5B,0x3D,0xC2,0x00,0x7C,0xB8,0xA1,0x63,0xBF,0x05,
68 0x98,0xDA,0x48,0x36,0x1C,0x55,0xD3,0x9A,0x69,0x16,0x3F,0xA8,0xFD,0x24,0xCF,0x5F,
69 0x83,0x65,0x5D,0x23,0xDC,0xA3,0xAD,0x96,0x1C,0x62,0xF3,0x56,0x20,0x85,0x52,0xBB,
70 0x9E,0xD5,0x29,0x07,0x70,0x96,0x96,0x6D,0x67,0x0C,0x35,0x4E,0x4A,0xBC,0x98,0x04,
71 0xF1,0x74,0x6C,0x08,0xCA,0x23,0x73,0x27,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
72 };
73 /**
74 * Modulus of Group 14 (MODP_2048_BIT).
75 */
76 static u_int8_t group14_modulus[] = {
77 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
78 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
79 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
80 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
81 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
82 0xF4,0x4C,0x42,0xE9,0xA6,0x37,0xED,0x6B,0x0B,0xFF,0x5C,0xB6,0xF4,0x06,0xB7,0xED,
83 0xEE,0x38,0x6B,0xFB,0x5A,0x89,0x9F,0xA5,0xAE,0x9F,0x24,0x11,0x7C,0x4B,0x1F,0xE6,
84 0x49,0x28,0x66,0x51,0xEC,0xE4,0x5B,0x3D,0xC2,0x00,0x7C,0xB8,0xA1,0x63,0xBF,0x05,
85 0x98,0xDA,0x48,0x36,0x1C,0x55,0xD3,0x9A,0x69,0x16,0x3F,0xA8,0xFD,0x24,0xCF,0x5F,
86 0x83,0x65,0x5D,0x23,0xDC,0xA3,0xAD,0x96,0x1C,0x62,0xF3,0x56,0x20,0x85,0x52,0xBB,
87 0x9E,0xD5,0x29,0x07,0x70,0x96,0x96,0x6D,0x67,0x0C,0x35,0x4E,0x4A,0xBC,0x98,0x04,
88 0xF1,0x74,0x6C,0x08,0xCA,0x18,0x21,0x7C,0x32,0x90,0x5E,0x46,0x2E,0x36,0xCE,0x3B,
89 0xE3,0x9E,0x77,0x2C,0x18,0x0E,0x86,0x03,0x9B,0x27,0x83,0xA2,0xEC,0x07,0xA2,0x8F,
90 0xB5,0xC5,0x5D,0xF0,0x6F,0x4C,0x52,0xC9,0xDE,0x2B,0xCB,0xF6,0x95,0x58,0x17,0x18,
91 0x39,0x95,0x49,0x7C,0xEA,0x95,0x6A,0xE5,0x15,0xD2,0x26,0x18,0x98,0xFA,0x05,0x10,
92 0x15,0x72,0x8E,0x5A,0x8A,0xAC,0xAA,0x68,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
93 };
94
95 /**
96 * Modulus of Group 15 (MODP_3072_BIT).
97 */
98 static u_int8_t group15_modulus[] = {
99 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
100 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
101 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
102 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
103 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
104 0xF4,0x4C,0x42,0xE9,0xA6,0x37,0xED,0x6B,0x0B,0xFF,0x5C,0xB6,0xF4,0x06,0xB7,0xED,
105 0xEE,0x38,0x6B,0xFB,0x5A,0x89,0x9F,0xA5,0xAE,0x9F,0x24,0x11,0x7C,0x4B,0x1F,0xE6,
106 0x49,0x28,0x66,0x51,0xEC,0xE4,0x5B,0x3D,0xC2,0x00,0x7C,0xB8,0xA1,0x63,0xBF,0x05,
107 0x98,0xDA,0x48,0x36,0x1C,0x55,0xD3,0x9A,0x69,0x16,0x3F,0xA8,0xFD,0x24,0xCF,0x5F,
108 0x83,0x65,0x5D,0x23,0xDC,0xA3,0xAD,0x96,0x1C,0x62,0xF3,0x56,0x20,0x85,0x52,0xBB,
109 0x9E,0xD5,0x29,0x07,0x70,0x96,0x96,0x6D,0x67,0x0C,0x35,0x4E,0x4A,0xBC,0x98,0x04,
110 0xF1,0x74,0x6C,0x08,0xCA,0x18,0x21,0x7C,0x32,0x90,0x5E,0x46,0x2E,0x36,0xCE,0x3B,
111 0xE3,0x9E,0x77,0x2C,0x18,0x0E,0x86,0x03,0x9B,0x27,0x83,0xA2,0xEC,0x07,0xA2,0x8F,
112 0xB5,0xC5,0x5D,0xF0,0x6F,0x4C,0x52,0xC9,0xDE,0x2B,0xCB,0xF6,0x95,0x58,0x17,0x18,
113 0x39,0x95,0x49,0x7C,0xEA,0x95,0x6A,0xE5,0x15,0xD2,0x26,0x18,0x98,0xFA,0x05,0x10,
114 0x15,0x72,0x8E,0x5A,0x8A,0xAA,0xC4,0x2D,0xAD,0x33,0x17,0x0D,0x04,0x50,0x7A,0x33,
115 0xA8,0x55,0x21,0xAB,0xDF,0x1C,0xBA,0x64,0xEC,0xFB,0x85,0x04,0x58,0xDB,0xEF,0x0A,
116 0x8A,0xEA,0x71,0x57,0x5D,0x06,0x0C,0x7D,0xB3,0x97,0x0F,0x85,0xA6,0xE1,0xE4,0xC7,
117 0xAB,0xF5,0xAE,0x8C,0xDB,0x09,0x33,0xD7,0x1E,0x8C,0x94,0xE0,0x4A,0x25,0x61,0x9D,
118 0xCE,0xE3,0xD2,0x26,0x1A,0xD2,0xEE,0x6B,0xF1,0x2F,0xFA,0x06,0xD9,0x8A,0x08,0x64,
119 0xD8,0x76,0x02,0x73,0x3E,0xC8,0x6A,0x64,0x52,0x1F,0x2B,0x18,0x17,0x7B,0x20,0x0C,
120 0xBB,0xE1,0x17,0x57,0x7A,0x61,0x5D,0x6C,0x77,0x09,0x88,0xC0,0xBA,0xD9,0x46,0xE2,
121 0x08,0xE2,0x4F,0xA0,0x74,0xE5,0xAB,0x31,0x43,0xDB,0x5B,0xFC,0xE0,0xFD,0x10,0x8E,
122 0x4B,0x82,0xD1,0x20,0xA9,0x3A,0xD2,0xCA,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
123 };
124
125 /**
126 * Modulus of Group 16 (MODP_4096_BIT).
127 */
128 static u_int8_t group16_modulus[] = {
129 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
130 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
131 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
132 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
133 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
134 0xF4,0x4C,0x42,0xE9,0xA6,0x37,0xED,0x6B,0x0B,0xFF,0x5C,0xB6,0xF4,0x06,0xB7,0xED,
135 0xEE,0x38,0x6B,0xFB,0x5A,0x89,0x9F,0xA5,0xAE,0x9F,0x24,0x11,0x7C,0x4B,0x1F,0xE6,
136 0x49,0x28,0x66,0x51,0xEC,0xE4,0x5B,0x3D,0xC2,0x00,0x7C,0xB8,0xA1,0x63,0xBF,0x05,
137 0x98,0xDA,0x48,0x36,0x1C,0x55,0xD3,0x9A,0x69,0x16,0x3F,0xA8,0xFD,0x24,0xCF,0x5F,
138 0x83,0x65,0x5D,0x23,0xDC,0xA3,0xAD,0x96,0x1C,0x62,0xF3,0x56,0x20,0x85,0x52,0xBB,
139 0x9E,0xD5,0x29,0x07,0x70,0x96,0x96,0x6D,0x67,0x0C,0x35,0x4E,0x4A,0xBC,0x98,0x04,
140 0xF1,0x74,0x6C,0x08,0xCA,0x18,0x21,0x7C,0x32,0x90,0x5E,0x46,0x2E,0x36,0xCE,0x3B,
141 0xE3,0x9E,0x77,0x2C,0x18,0x0E,0x86,0x03,0x9B,0x27,0x83,0xA2,0xEC,0x07,0xA2,0x8F,
142 0xB5,0xC5,0x5D,0xF0,0x6F,0x4C,0x52,0xC9,0xDE,0x2B,0xCB,0xF6,0x95,0x58,0x17,0x18,
143 0x39,0x95,0x49,0x7C,0xEA,0x95,0x6A,0xE5,0x15,0xD2,0x26,0x18,0x98,0xFA,0x05,0x10,
144 0x15,0x72,0x8E,0x5A,0x8A,0xAA,0xC4,0x2D,0xAD,0x33,0x17,0x0D,0x04,0x50,0x7A,0x33,
145 0xA8,0x55,0x21,0xAB,0xDF,0x1C,0xBA,0x64,0xEC,0xFB,0x85,0x04,0x58,0xDB,0xEF,0x0A,
146 0x8A,0xEA,0x71,0x57,0x5D,0x06,0x0C,0x7D,0xB3,0x97,0x0F,0x85,0xA6,0xE1,0xE4,0xC7,
147 0xAB,0xF5,0xAE,0x8C,0xDB,0x09,0x33,0xD7,0x1E,0x8C,0x94,0xE0,0x4A,0x25,0x61,0x9D,
148 0xCE,0xE3,0xD2,0x26,0x1A,0xD2,0xEE,0x6B,0xF1,0x2F,0xFA,0x06,0xD9,0x8A,0x08,0x64,
149 0xD8,0x76,0x02,0x73,0x3E,0xC8,0x6A,0x64,0x52,0x1F,0x2B,0x18,0x17,0x7B,0x20,0x0C,
150 0xBB,0xE1,0x17,0x57,0x7A,0x61,0x5D,0x6C,0x77,0x09,0x88,0xC0,0xBA,0xD9,0x46,0xE2,
151 0x08,0xE2,0x4F,0xA0,0x74,0xE5,0xAB,0x31,0x43,0xDB,0x5B,0xFC,0xE0,0xFD,0x10,0x8E,
152 0x4B,0x82,0xD1,0x20,0xA9,0x21,0x08,0x01,0x1A,0x72,0x3C,0x12,0xA7,0x87,0xE6,0xD7,
153 0x88,0x71,0x9A,0x10,0xBD,0xBA,0x5B,0x26,0x99,0xC3,0x27,0x18,0x6A,0xF4,0xE2,0x3C,
154 0x1A,0x94,0x68,0x34,0xB6,0x15,0x0B,0xDA,0x25,0x83,0xE9,0xCA,0x2A,0xD4,0x4C,0xE8,
155 0xDB,0xBB,0xC2,0xDB,0x04,0xDE,0x8E,0xF9,0x2E,0x8E,0xFC,0x14,0x1F,0xBE,0xCA,0xA6,
156 0x28,0x7C,0x59,0x47,0x4E,0x6B,0xC0,0x5D,0x99,0xB2,0x96,0x4F,0xA0,0x90,0xC3,0xA2,
157 0x23,0x3B,0xA1,0x86,0x51,0x5B,0xE7,0xED,0x1F,0x61,0x29,0x70,0xCE,0xE2,0xD7,0xAF,
158 0xB8,0x1B,0xDD,0x76,0x21,0x70,0x48,0x1C,0xD0,0x06,0x91,0x27,0xD5,0xB0,0x5A,0xA9,
159 0x93,0xB4,0xEA,0x98,0x8D,0x8F,0xDD,0xC1,0x86,0xFF,0xB7,0xDC,0x90,0xA6,0xC0,0x8F,
160 0x4D,0xF4,0x35,0xC9,0x34,0x06,0x31,0x99,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
161 };
162
163 /**
164 * Modulus of Group 17 (MODP_6144_BIT).
165 */
166 static u_int8_t group17_modulus[] = {
167 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
168 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
169 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
170 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
171 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
172 0xF4,0x4C,0x42,0xE9,0xA6,0x37,0xED,0x6B,0x0B,0xFF,0x5C,0xB6,0xF4,0x06,0xB7,0xED,
173 0xEE,0x38,0x6B,0xFB,0x5A,0x89,0x9F,0xA5,0xAE,0x9F,0x24,0x11,0x7C,0x4B,0x1F,0xE6,
174 0x49,0x28,0x66,0x51,0xEC,0xE4,0x5B,0x3D,0xC2,0x00,0x7C,0xB8,0xA1,0x63,0xBF,0x05,
175 0x98,0xDA,0x48,0x36,0x1C,0x55,0xD3,0x9A,0x69,0x16,0x3F,0xA8,0xFD,0x24,0xCF,0x5F,
176 0x83,0x65,0x5D,0x23,0xDC,0xA3,0xAD,0x96,0x1C,0x62,0xF3,0x56,0x20,0x85,0x52,0xBB,
177 0x9E,0xD5,0x29,0x07,0x70,0x96,0x96,0x6D,0x67,0x0C,0x35,0x4E,0x4A,0xBC,0x98,0x04,
178 0xF1,0x74,0x6C,0x08,0xCA,0x18,0x21,0x7C,0x32,0x90,0x5E,0x46,0x2E,0x36,0xCE,0x3B,
179 0xE3,0x9E,0x77,0x2C,0x18,0x0E,0x86,0x03,0x9B,0x27,0x83,0xA2,0xEC,0x07,0xA2,0x8F,
180 0xB5,0xC5,0x5D,0xF0,0x6F,0x4C,0x52,0xC9,0xDE,0x2B,0xCB,0xF6,0x95,0x58,0x17,0x18,
181 0x39,0x95,0x49,0x7C,0xEA,0x95,0x6A,0xE5,0x15,0xD2,0x26,0x18,0x98,0xFA,0x05,0x10,
182 0x15,0x72,0x8E,0x5A,0x8A,0xAA,0xC4,0x2D,0xAD,0x33,0x17,0x0D,0x04,0x50,0x7A,0x33,
183 0xA8,0x55,0x21,0xAB,0xDF,0x1C,0xBA,0x64,0xEC,0xFB,0x85,0x04,0x58,0xDB,0xEF,0x0A,
184 0x8A,0xEA,0x71,0x57,0x5D,0x06,0x0C,0x7D,0xB3,0x97,0x0F,0x85,0xA6,0xE1,0xE4,0xC7,
185 0xAB,0xF5,0xAE,0x8C,0xDB,0x09,0x33,0xD7,0x1E,0x8C,0x94,0xE0,0x4A,0x25,0x61,0x9D,
186 0xCE,0xE3,0xD2,0x26,0x1A,0xD2,0xEE,0x6B,0xF1,0x2F,0xFA,0x06,0xD9,0x8A,0x08,0x64,
187 0xD8,0x76,0x02,0x73,0x3E,0xC8,0x6A,0x64,0x52,0x1F,0x2B,0x18,0x17,0x7B,0x20,0x0C,
188 0xBB,0xE1,0x17,0x57,0x7A,0x61,0x5D,0x6C,0x77,0x09,0x88,0xC0,0xBA,0xD9,0x46,0xE2,
189 0x08,0xE2,0x4F,0xA0,0x74,0xE5,0xAB,0x31,0x43,0xDB,0x5B,0xFC,0xE0,0xFD,0x10,0x8E,
190 0x4B,0x82,0xD1,0x20,0xA9,0x21,0x08,0x01,0x1A,0x72,0x3C,0x12,0xA7,0x87,0xE6,0xD7,
191 0x88,0x71,0x9A,0x10,0xBD,0xBA,0x5B,0x26,0x99,0xC3,0x27,0x18,0x6A,0xF4,0xE2,0x3C,
192 0x1A,0x94,0x68,0x34,0xB6,0x15,0x0B,0xDA,0x25,0x83,0xE9,0xCA,0x2A,0xD4,0x4C,0xE8,
193 0xDB,0xBB,0xC2,0xDB,0x04,0xDE,0x8E,0xF9,0x2E,0x8E,0xFC,0x14,0x1F,0xBE,0xCA,0xA6,
194 0x28,0x7C,0x59,0x47,0x4E,0x6B,0xC0,0x5D,0x99,0xB2,0x96,0x4F,0xA0,0x90,0xC3,0xA2,
195 0x23,0x3B,0xA1,0x86,0x51,0x5B,0xE7,0xED,0x1F,0x61,0x29,0x70,0xCE,0xE2,0xD7,0xAF,
196 0xB8,0x1B,0xDD,0x76,0x21,0x70,0x48,0x1C,0xD0,0x06,0x91,0x27,0xD5,0xB0,0x5A,0xA9,
197 0x93,0xB4,0xEA,0x98,0x8D,0x8F,0xDD,0xC1,0x86,0xFF,0xB7,0xDC,0x90,0xA6,0xC0,0x8F,
198 0x4D,0xF4,0x35,0xC9,0x34,0x02,0x84,0x92,0x36,0xC3,0xFA,0xB4,0xD2,0x7C,0x70,0x26,
199 0xC1,0xD4,0xDC,0xB2,0x60,0x26,0x46,0xDE,0xC9,0x75,0x1E,0x76,0x3D,0xBA,0x37,0xBD,
200 0xF8,0xFF,0x94,0x06,0xAD,0x9E,0x53,0x0E,0xE5,0xDB,0x38,0x2F,0x41,0x30,0x01,0xAE,
201 0xB0,0x6A,0x53,0xED,0x90,0x27,0xD8,0x31,0x17,0x97,0x27,0xB0,0x86,0x5A,0x89,0x18,
202 0xDA,0x3E,0xDB,0xEB,0xCF,0x9B,0x14,0xED,0x44,0xCE,0x6C,0xBA,0xCE,0xD4,0xBB,0x1B,
203 0xDB,0x7F,0x14,0x47,0xE6,0xCC,0x25,0x4B,0x33,0x20,0x51,0x51,0x2B,0xD7,0xAF,0x42,
204 0x6F,0xB8,0xF4,0x01,0x37,0x8C,0xD2,0xBF,0x59,0x83,0xCA,0x01,0xC6,0x4B,0x92,0xEC,
205 0xF0,0x32,0xEA,0x15,0xD1,0x72,0x1D,0x03,0xF4,0x82,0xD7,0xCE,0x6E,0x74,0xFE,0xF6,
206 0xD5,0x5E,0x70,0x2F,0x46,0x98,0x0C,0x82,0xB5,0xA8,0x40,0x31,0x90,0x0B,0x1C,0x9E,
207 0x59,0xE7,0xC9,0x7F,0xBE,0xC7,0xE8,0xF3,0x23,0xA9,0x7A,0x7E,0x36,0xCC,0x88,0xBE,
208 0x0F,0x1D,0x45,0xB7,0xFF,0x58,0x5A,0xC5,0x4B,0xD4,0x07,0xB2,0x2B,0x41,0x54,0xAA,
209 0xCC,0x8F,0x6D,0x7E,0xBF,0x48,0xE1,0xD8,0x14,0xCC,0x5E,0xD2,0x0F,0x80,0x37,0xE0,
210 0xA7,0x97,0x15,0xEE,0xF2,0x9B,0xE3,0x28,0x06,0xA1,0xD5,0x8B,0xB7,0xC5,0xDA,0x76,
211 0xF5,0x50,0xAA,0x3D,0x8A,0x1F,0xBF,0xF0,0xEB,0x19,0xCC,0xB1,0xA3,0x13,0xD5,0x5C,
212 0xDA,0x56,0xC9,0xEC,0x2E,0xF2,0x96,0x32,0x38,0x7F,0xE8,0xD7,0x6E,0x3C,0x04,0x68,
213 0x04,0x3E,0x8F,0x66,0x3F,0x48,0x60,0xEE,0x12,0xBF,0x2D,0x5B,0x0B,0x74,0x74,0xD6,
214 0xE6,0x94,0xF9,0x1E,0x6D,0xCC,0x40,0x24,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
215 };
216
217 /**
218 * Modulus of Group 18 (MODP_8192_BIT).
219 */
220 static u_int8_t group18_modulus[] = {
221 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xC9,0x0F,0xDA,0xA2,0x21,0x68,0xC2,0x34,
222 0xC4,0xC6,0x62,0x8B,0x80,0xDC,0x1C,0xD1,0x29,0x02,0x4E,0x08,0x8A,0x67,0xCC,0x74,
223 0x02,0x0B,0xBE,0xA6,0x3B,0x13,0x9B,0x22,0x51,0x4A,0x08,0x79,0x8E,0x34,0x04,0xDD,
224 0xEF,0x95,0x19,0xB3,0xCD,0x3A,0x43,0x1B,0x30,0x2B,0x0A,0x6D,0xF2,0x5F,0x14,0x37,
225 0x4F,0xE1,0x35,0x6D,0x6D,0x51,0xC2,0x45,0xE4,0x85,0xB5,0x76,0x62,0x5E,0x7E,0xC6,
226 0xF4,0x4C,0x42,0xE9,0xA6,0x37,0xED,0x6B,0x0B,0xFF,0x5C,0xB6,0xF4,0x06,0xB7,0xED,
227 0xEE,0x38,0x6B,0xFB,0x5A,0x89,0x9F,0xA5,0xAE,0x9F,0x24,0x11,0x7C,0x4B,0x1F,0xE6,
228 0x49,0x28,0x66,0x51,0xEC,0xE4,0x5B,0x3D,0xC2,0x00,0x7C,0xB8,0xA1,0x63,0xBF,0x05,
229 0x98,0xDA,0x48,0x36,0x1C,0x55,0xD3,0x9A,0x69,0x16,0x3F,0xA8,0xFD,0x24,0xCF,0x5F,
230 0x83,0x65,0x5D,0x23,0xDC,0xA3,0xAD,0x96,0x1C,0x62,0xF3,0x56,0x20,0x85,0x52,0xBB,
231 0x9E,0xD5,0x29,0x07,0x70,0x96,0x96,0x6D,0x67,0x0C,0x35,0x4E,0x4A,0xBC,0x98,0x04,
232 0xF1,0x74,0x6C,0x08,0xCA,0x18,0x21,0x7C,0x32,0x90,0x5E,0x46,0x2E,0x36,0xCE,0x3B,
233 0xE3,0x9E,0x77,0x2C,0x18,0x0E,0x86,0x03,0x9B,0x27,0x83,0xA2,0xEC,0x07,0xA2,0x8F,
234 0xB5,0xC5,0x5D,0xF0,0x6F,0x4C,0x52,0xC9,0xDE,0x2B,0xCB,0xF6,0x95,0x58,0x17,0x18,
235 0x39,0x95,0x49,0x7C,0xEA,0x95,0x6A,0xE5,0x15,0xD2,0x26,0x18,0x98,0xFA,0x05,0x10,
236 0x15,0x72,0x8E,0x5A,0x8A,0xAA,0xC4,0x2D,0xAD,0x33,0x17,0x0D,0x04,0x50,0x7A,0x33,
237 0xA8,0x55,0x21,0xAB,0xDF,0x1C,0xBA,0x64,0xEC,0xFB,0x85,0x04,0x58,0xDB,0xEF,0x0A,
238 0x8A,0xEA,0x71,0x57,0x5D,0x06,0x0C,0x7D,0xB3,0x97,0x0F,0x85,0xA6,0xE1,0xE4,0xC7,
239 0xAB,0xF5,0xAE,0x8C,0xDB,0x09,0x33,0xD7,0x1E,0x8C,0x94,0xE0,0x4A,0x25,0x61,0x9D,
240 0xCE,0xE3,0xD2,0x26,0x1A,0xD2,0xEE,0x6B,0xF1,0x2F,0xFA,0x06,0xD9,0x8A,0x08,0x64,
241 0xD8,0x76,0x02,0x73,0x3E,0xC8,0x6A,0x64,0x52,0x1F,0x2B,0x18,0x17,0x7B,0x20,0x0C,
242 0xBB,0xE1,0x17,0x57,0x7A,0x61,0x5D,0x6C,0x77,0x09,0x88,0xC0,0xBA,0xD9,0x46,0xE2,
243 0x08,0xE2,0x4F,0xA0,0x74,0xE5,0xAB,0x31,0x43,0xDB,0x5B,0xFC,0xE0,0xFD,0x10,0x8E,
244 0x4B,0x82,0xD1,0x20,0xA9,0x21,0x08,0x01,0x1A,0x72,0x3C,0x12,0xA7,0x87,0xE6,0xD7,
245 0x88,0x71,0x9A,0x10,0xBD,0xBA,0x5B,0x26,0x99,0xC3,0x27,0x18,0x6A,0xF4,0xE2,0x3C,
246 0x1A,0x94,0x68,0x34,0xB6,0x15,0x0B,0xDA,0x25,0x83,0xE9,0xCA,0x2A,0xD4,0x4C,0xE8,
247 0xDB,0xBB,0xC2,0xDB,0x04,0xDE,0x8E,0xF9,0x2E,0x8E,0xFC,0x14,0x1F,0xBE,0xCA,0xA6,
248 0x28,0x7C,0x59,0x47,0x4E,0x6B,0xC0,0x5D,0x99,0xB2,0x96,0x4F,0xA0,0x90,0xC3,0xA2,
249 0x23,0x3B,0xA1,0x86,0x51,0x5B,0xE7,0xED,0x1F,0x61,0x29,0x70,0xCE,0xE2,0xD7,0xAF,
250 0xB8,0x1B,0xDD,0x76,0x21,0x70,0x48,0x1C,0xD0,0x06,0x91,0x27,0xD5,0xB0,0x5A,0xA9,
251 0x93,0xB4,0xEA,0x98,0x8D,0x8F,0xDD,0xC1,0x86,0xFF,0xB7,0xDC,0x90,0xA6,0xC0,0x8F,
252 0x4D,0xF4,0x35,0xC9,0x34,0x02,0x84,0x92,0x36,0xC3,0xFA,0xB4,0xD2,0x7C,0x70,0x26,
253 0xC1,0xD4,0xDC,0xB2,0x60,0x26,0x46,0xDE,0xC9,0x75,0x1E,0x76,0x3D,0xBA,0x37,0xBD,
254 0xF8,0xFF,0x94,0x06,0xAD,0x9E,0x53,0x0E,0xE5,0xDB,0x38,0x2F,0x41,0x30,0x01,0xAE,
255 0xB0,0x6A,0x53,0xED,0x90,0x27,0xD8,0x31,0x17,0x97,0x27,0xB0,0x86,0x5A,0x89,0x18,
256 0xDA,0x3E,0xDB,0xEB,0xCF,0x9B,0x14,0xED,0x44,0xCE,0x6C,0xBA,0xCE,0xD4,0xBB,0x1B,
257 0xDB,0x7F,0x14,0x47,0xE6,0xCC,0x25,0x4B,0x33,0x20,0x51,0x51,0x2B,0xD7,0xAF,0x42,
258 0x6F,0xB8,0xF4,0x01,0x37,0x8C,0xD2,0xBF,0x59,0x83,0xCA,0x01,0xC6,0x4B,0x92,0xEC,
259 0xF0,0x32,0xEA,0x15,0xD1,0x72,0x1D,0x03,0xF4,0x82,0xD7,0xCE,0x6E,0x74,0xFE,0xF6,
260 0xD5,0x5E,0x70,0x2F,0x46,0x98,0x0C,0x82,0xB5,0xA8,0x40,0x31,0x90,0x0B,0x1C,0x9E,
261 0x59,0xE7,0xC9,0x7F,0xBE,0xC7,0xE8,0xF3,0x23,0xA9,0x7A,0x7E,0x36,0xCC,0x88,0xBE,
262 0x0F,0x1D,0x45,0xB7,0xFF,0x58,0x5A,0xC5,0x4B,0xD4,0x07,0xB2,0x2B,0x41,0x54,0xAA,
263 0xCC,0x8F,0x6D,0x7E,0xBF,0x48,0xE1,0xD8,0x14,0xCC,0x5E,0xD2,0x0F,0x80,0x37,0xE0,
264 0xA7,0x97,0x15,0xEE,0xF2,0x9B,0xE3,0x28,0x06,0xA1,0xD5,0x8B,0xB7,0xC5,0xDA,0x76,
265 0xF5,0x50,0xAA,0x3D,0x8A,0x1F,0xBF,0xF0,0xEB,0x19,0xCC,0xB1,0xA3,0x13,0xD5,0x5C,
266 0xDA,0x56,0xC9,0xEC,0x2E,0xF2,0x96,0x32,0x38,0x7F,0xE8,0xD7,0x6E,0x3C,0x04,0x68,
267 0x04,0x3E,0x8F,0x66,0x3F,0x48,0x60,0xEE,0x12,0xBF,0x2D,0x5B,0x0B,0x74,0x74,0xD6,
268 0xE6,0x94,0xF9,0x1E,0x6D,0xBE,0x11,0x59,0x74,0xA3,0x92,0x6F,0x12,0xFE,0xE5,0xE4,
269 0x38,0x77,0x7C,0xB6,0xA9,0x32,0xDF,0x8C,0xD8,0xBE,0xC4,0xD0,0x73,0xB9,0x31,0xBA,
270 0x3B,0xC8,0x32,0xB6,0x8D,0x9D,0xD3,0x00,0x74,0x1F,0xA7,0xBF,0x8A,0xFC,0x47,0xED,
271 0x25,0x76,0xF6,0x93,0x6B,0xA4,0x24,0x66,0x3A,0xAB,0x63,0x9C,0x5A,0xE4,0xF5,0x68,
272 0x34,0x23,0xB4,0x74,0x2B,0xF1,0xC9,0x78,0x23,0x8F,0x16,0xCB,0xE3,0x9D,0x65,0x2D,
273 0xE3,0xFD,0xB8,0xBE,0xFC,0x84,0x8A,0xD9,0x22,0x22,0x2E,0x04,0xA4,0x03,0x7C,0x07,
274 0x13,0xEB,0x57,0xA8,0x1A,0x23,0xF0,0xC7,0x34,0x73,0xFC,0x64,0x6C,0xEA,0x30,0x6B,
275 0x4B,0xCB,0xC8,0x86,0x2F,0x83,0x85,0xDD,0xFA,0x9D,0x4B,0x7F,0xA2,0xC0,0x87,0xE8,
276 0x79,0x68,0x33,0x03,0xED,0x5B,0xDD,0x3A,0x06,0x2B,0x3C,0xF5,0xB3,0xA2,0x78,0xA6,
277 0x6D,0x2A,0x13,0xF8,0x3F,0x44,0xF8,0x2D,0xDF,0x31,0x0E,0xE0,0x74,0xAB,0x6A,0x36,
278 0x45,0x97,0xE8,0x99,0xA0,0x25,0x5D,0xC1,0x64,0xF3,0x1C,0xC5,0x08,0x46,0x85,0x1D,
279 0xF9,0xAB,0x48,0x19,0x5D,0xED,0x7E,0xA1,0xB1,0xD5,0x10,0xBD,0x7E,0xE7,0x4D,0x73,
280 0xFA,0xF3,0x6B,0xC3,0x1E,0xCF,0xA2,0x68,0x35,0x90,0x46,0xF4,0xEB,0x87,0x9F,0x92,
281 0x40,0x09,0x43,0x8B,0x48,0x1C,0x6C,0xD7,0x88,0x9A,0x00,0x2E,0xD5,0xEE,0x38,0x2B,
282 0xC9,0x19,0x0D,0xA6,0xFC,0x02,0x6E,0x47,0x95,0x58,0xE4,0x47,0x56,0x77,0xE9,0xAA,
283 0x9E,0x30,0x50,0xE2,0x76,0x56,0x94,0xDF,0xC8,0x1F,0x56,0xE8,0x80,0xB9,0x6E,0x71,
284 0x60,0xC9,0x80,0xDD,0x98,0xED,0xD3,0xDF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
285 };
286
287 typedef struct modulus_entry_t modulus_entry_t;
288
289 /**
290 * Entry of the modulus list.
291 */
292 struct modulus_entry_t {
293 /**
294 * Group number as it is defined in file transform_substructure.h.
295 */
296 diffie_hellman_group_t group;
297
298 /**
299 * Pointer to first byte of modulus (network order).
300 */
301 u_int8_t *modulus;
302
303 /*
304 * Length of modulus in bytes.
305 */
306 size_t modulus_len;
307
308 /*
309 * Optimum length of exponent in bytes.
310 */
311 size_t opt_exponent_len;
312
313 /*
314 * Generator value.
315 */
316 u_int16_t generator;
317 };
318
319 /**
320 * All supported modulus values - optimum exponent size according to RFC 3526.
321 */
322 static modulus_entry_t modulus_entries[] = {
323 {MODP_768_BIT, group1_modulus, sizeof(group1_modulus), 32, 2},
324 {MODP_1024_BIT, group2_modulus, sizeof(group2_modulus), 32, 2},
325 {MODP_1536_BIT, group5_modulus, sizeof(group5_modulus), 32, 2},
326 {MODP_2048_BIT, group14_modulus, sizeof(group14_modulus), 48, 2},
327 {MODP_3072_BIT, group15_modulus, sizeof(group15_modulus), 48, 2},
328 {MODP_4096_BIT, group16_modulus, sizeof(group16_modulus), 64, 2},
329 {MODP_6144_BIT, group17_modulus, sizeof(group17_modulus), 64, 2},
330 {MODP_8192_BIT, group18_modulus, sizeof(group18_modulus), 64, 2},
331 };
332
333 typedef struct private_gmp_diffie_hellman_t private_gmp_diffie_hellman_t;
334
335 /**
336 * Private data of an gmp_diffie_hellman_t object.
337 */
338 struct private_gmp_diffie_hellman_t {
339 /**
340 * Public gmp_diffie_hellman_t interface.
341 */
342 gmp_diffie_hellman_t public;
343
344 /**
345 * Diffie Hellman group number.
346 */
347 u_int16_t group;
348
349 /*
350 * Generator value.
351 */
352 mpz_t g;
353
354 /**
355 * My private value.
356 */
357 mpz_t xa;
358
359 /**
360 * My public value.
361 */
362 mpz_t ya;
363
364 /**
365 * Other public value.
366 */
367 mpz_t yb;
368
369 /**
370 * Shared secret.
371 */
372 mpz_t zz;
373
374 /**
375 * Modulus.
376 */
377 mpz_t p;
378
379 /**
380 * Modulus length.
381 */
382 size_t p_len;
383
384 /**
385 * Optimal exponent length.
386 */
387 size_t opt_exponent_len;
388
389 /**
390 * True if shared secret is computed and stored in my_public_value.
391 */
392 bool computed;
393 };
394
395 /**
396 * Implementation of gmp_diffie_hellman_t.set_other_public_value.
397 */
398 static void set_other_public_value(private_gmp_diffie_hellman_t *this, chunk_t value)
399 {
400 mpz_t p_min_1;
401
402 mpz_init(p_min_1);
403 mpz_sub_ui(p_min_1, this->p, 1);
404
405 mpz_import(this->yb, value.len, 1, 1, 1, 0, value.ptr);
406
407 /* check public value:
408 * 1. 0 or 1 is invalid as 0^a = 0 and 1^a = 1
409 * 2. a public value larger or equal the modulus is invalid */
410 if (mpz_cmp_ui(this->yb, 1) > 0 &&
411 mpz_cmp(this->yb, p_min_1) < 0)
412 {
413 #ifdef EXTENDED_DH_TEST
414 /* 3. test if y ^ q mod p = 1, where q = (p - 1)/2. */
415 mpz_t q, one;
416
417 mpz_init(q);
418 mpz_init(one);
419 mpz_fdiv_q_2exp(q, p_min_1, 1);
420 mpz_powm(one, this->yb, q, this->p);
421 mpz_clear(q);
422 if (mpz_cmp_ui(one, 1) == 0)
423 {
424 mpz_powm(this->zz, this->yb, this->xa, this->p);
425 this->computed = TRUE;
426 }
427 else
428 {
429 DBG1("public DH value verification failed: y ^ q mod p != 1");
430 }
431 mpz_clear(one);
432 #else
433 mpz_powm(this->zz, this->yb, this->xa, this->p);
434 this->computed = TRUE;
435 #endif
436 }
437 else
438 {
439 DBG1("public DH value verification failed: y < 2 || y > p - 1 ");
440 }
441 mpz_clear(p_min_1);
442 }
443
444 /**
445 * Implementation of gmp_diffie_hellman_t.get_my_public_value.
446 */
447 static void get_my_public_value(private_gmp_diffie_hellman_t *this,chunk_t *value)
448 {
449 value->len = this->p_len;
450 value->ptr = mpz_export(NULL, NULL, 1, value->len, 1, 0, this->ya);
451 if (value->ptr == NULL)
452 {
453 value->len = 0;
454 }
455 }
456
457 /**
458 * Implementation of gmp_diffie_hellman_t.get_shared_secret.
459 */
460 static status_t get_shared_secret(private_gmp_diffie_hellman_t *this, chunk_t *secret)
461 {
462 if (!this->computed)
463 {
464 return FAILED;
465 }
466 secret->len = this->p_len;
467 secret->ptr = mpz_export(NULL, NULL, 1, secret->len, 1, 0, this->zz);
468 if (secret->ptr == NULL)
469 {
470 return FAILED;
471 }
472 return SUCCESS;
473 }
474
475 /**
476 * Implementation of gmp_diffie_hellman_t.get_dh_group.
477 */
478 static diffie_hellman_group_t get_dh_group(private_gmp_diffie_hellman_t *this)
479 {
480 return this->group;
481 }
482
483 /**
484 * Lookup the modulus in modulo table
485 */
486 static status_t set_modulus(private_gmp_diffie_hellman_t *this)
487 {
488 int i;
489 status_t status = NOT_FOUND;
490
491 for (i = 0; i < (sizeof(modulus_entries) / sizeof(modulus_entry_t)); i++)
492 {
493 if (modulus_entries[i].group == this->group)
494 {
495 chunk_t chunk;
496 chunk.ptr = modulus_entries[i].modulus;
497 chunk.len = modulus_entries[i].modulus_len;
498 mpz_import(this->p, chunk.len, 1, 1, 1, 0, chunk.ptr);
499 this->p_len = chunk.len;
500 this->opt_exponent_len = modulus_entries[i].opt_exponent_len;
501 mpz_set_ui(this->g, modulus_entries[i].generator);
502 status = SUCCESS;
503 break;
504 }
505 }
506 return status;
507 }
508
509 /**
510 * Implementation of gmp_diffie_hellman_t.destroy.
511 */
512 static void destroy(private_gmp_diffie_hellman_t *this)
513 {
514 mpz_clear(this->p);
515 mpz_clear(this->xa);
516 mpz_clear(this->ya);
517 mpz_clear(this->yb);
518 mpz_clear(this->zz);
519 mpz_clear(this->g);
520 free(this);
521 }
522
523 /*
524 * Described in header.
525 */
526 gmp_diffie_hellman_t *gmp_diffie_hellman_create(diffie_hellman_group_t group)
527 {
528 private_gmp_diffie_hellman_t *this = malloc_thing(private_gmp_diffie_hellman_t);
529 rng_t *rng;
530 chunk_t random;
531 bool ansi_x9_42;
532 size_t exponent_len;
533
534 /* public functions */
535 this->public.dh.get_shared_secret = (status_t (*)(diffie_hellman_t *, chunk_t *)) get_shared_secret;
536 this->public.dh.set_other_public_value = (void (*)(diffie_hellman_t *, chunk_t )) set_other_public_value;
537 this->public.dh.get_my_public_value = (void (*)(diffie_hellman_t *, chunk_t *)) get_my_public_value;
538 this->public.dh.get_dh_group = (diffie_hellman_group_t (*)(diffie_hellman_t *)) get_dh_group;
539 this->public.dh.destroy = (void (*)(diffie_hellman_t *)) destroy;
540
541 /* private variables */
542 this->group = group;
543 mpz_init(this->p);
544 mpz_init(this->yb);
545 mpz_init(this->ya);
546 mpz_init(this->xa);
547 mpz_init(this->zz);
548 mpz_init(this->g);
549
550 this->computed = FALSE;
551
552 /* find a modulus according to group */
553 if (set_modulus(this) != SUCCESS)
554 {
555 destroy(this);
556 return NULL;
557 }
558 rng = lib->crypto->create_rng(lib->crypto, RNG_STRONG);
559 if (!rng)
560 {
561 DBG1("no RNG found for quality %N", rng_quality_names, RNG_STRONG);
562 destroy(this);
563 return NULL;
564 }
565
566 ansi_x9_42 = lib->settings->get_int(lib->settings,
567 "libstrongswan.dh_exponent_ansi_x9_42", TRUE);
568 exponent_len = (ansi_x9_42) ? this->p_len : this->opt_exponent_len;
569 rng->allocate_bytes(rng, exponent_len, &random);
570 rng->destroy(rng);
571
572 if (ansi_x9_42)
573 {
574 /* achieve bitsof(p)-1 by setting MSB to 0 */
575 *random.ptr &= 0x7F;
576 }
577 mpz_import(this->xa, random.len, 1, 1, 1, 0, random.ptr);
578 chunk_free(&random);
579 DBG2("size of DH secret exponent: %u bits", mpz_sizeinbase(this->xa, 2));
580
581 mpz_powm(this->ya, this->g, this->xa, this->p);
582
583 return &this->public;
584 }
585