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