1 | /* dsa.c
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2 | *
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3 | * Copyright (C) 2006-2020 wolfSSL Inc.
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4 | *
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5 | * This file is part of wolfSSL.
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6 | *
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7 | * wolfSSL is free software; you can redistribute it and/or modify
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8 | * it under the terms of the GNU General Public License as published by
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9 | * the Free Software Foundation; either version 2 of the License, or
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10 | * (at your option) any later version.
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11 | *
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12 | * wolfSSL is distributed in the hope that it will be useful,
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13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
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14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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15 | * GNU General Public License for more details.
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16 | *
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17 | * You should have received a copy of the GNU General Public License
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18 | * along with this program; if not, write to the Free Software
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19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
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20 | */
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21 |
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22 |
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23 | #ifdef HAVE_CONFIG_H
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24 | #include <config.h>
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25 | #endif
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26 |
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27 | #include <wolfssl/wolfcrypt/settings.h>
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28 |
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29 | #ifndef NO_DSA
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30 |
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31 | #include <wolfssl/wolfcrypt/random.h>
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32 | #include <wolfssl/wolfcrypt/integer.h>
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33 | #include <wolfssl/wolfcrypt/error-crypt.h>
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34 | #include <wolfssl/wolfcrypt/logging.h>
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35 | #include <wolfssl/wolfcrypt/sha.h>
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36 | #include <wolfssl/wolfcrypt/dsa.h>
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37 |
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38 | #ifdef NO_INLINE
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39 | #include <wolfssl/wolfcrypt/misc.h>
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40 | #else
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41 | #define WOLFSSL_MISC_INCLUDED
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42 | #include <wolfcrypt/src/misc.c>
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43 | #endif
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44 |
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45 | #ifdef _MSC_VER
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46 | /* disable for while(0) cases (MSVC bug) */
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47 | #pragma warning(disable:4127)
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48 | #endif
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49 |
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50 | int wc_InitDsaKey(DsaKey* key)
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51 | {
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52 | if (key == NULL)
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53 | return BAD_FUNC_ARG;
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54 |
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55 | key->type = -1; /* haven't decided yet */
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56 | key->heap = NULL;
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57 |
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58 | return mp_init_multi(
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59 | /* public alloc parts */
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60 | &key->p,
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61 | &key->q,
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62 | &key->g,
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63 | &key->y,
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64 |
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65 | /* private alloc parts */
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66 | &key->x,
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67 | NULL
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68 | );
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69 | }
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70 |
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71 |
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72 | int wc_InitDsaKey_h(DsaKey* key, void* h)
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73 | {
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74 | int ret = wc_InitDsaKey(key);
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75 | if (ret == 0)
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76 | key->heap = h;
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77 |
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78 | return ret;
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79 | }
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80 |
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81 |
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82 | void wc_FreeDsaKey(DsaKey* key)
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83 | {
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84 | if (key == NULL)
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85 | return;
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86 |
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87 | if (key->type == DSA_PRIVATE)
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88 | mp_forcezero(&key->x);
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89 |
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90 | mp_clear(&key->x);
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91 | mp_clear(&key->y);
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92 | mp_clear(&key->g);
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93 | mp_clear(&key->q);
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94 | mp_clear(&key->p);
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95 | }
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96 |
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97 |
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98 | /* validate that (L,N) match allowed sizes from FIPS 186-4, Section 4.2.
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99 | * modLen - represents L, the size of p (prime modulus) in bits
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100 | * divLen - represents N, the size of q (prime divisor) in bits
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101 | * return 0 on success, -1 on error */
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102 | static int CheckDsaLN(int modLen, int divLen)
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103 | {
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104 | int ret = -1;
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105 |
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106 | switch (modLen) {
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107 | case 1024:
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108 | if (divLen == 160)
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109 | ret = 0;
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110 | break;
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111 | case 2048:
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112 | if (divLen == 224 || divLen == 256)
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113 | ret = 0;
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114 | break;
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115 | case 3072:
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116 | if (divLen == 256)
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117 | ret = 0;
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118 | break;
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119 | default:
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120 | break;
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121 | }
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122 |
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123 | return ret;
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124 | }
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125 |
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126 |
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127 | #ifdef WOLFSSL_KEY_GEN
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128 |
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129 | /* Create DSA key pair (&dsa->x, &dsa->y)
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130 | *
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131 | * Based on NIST FIPS 186-4,
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132 | * "B.1.1 Key Pair Generation Using Extra Random Bits"
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133 | *
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134 | * rng - pointer to initialized WC_RNG structure
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135 | * dsa - pointer to initialized DsaKey structure, will hold generated key
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136 | *
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137 | * return 0 on success, negative on error */
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138 | int wc_MakeDsaKey(WC_RNG *rng, DsaKey *dsa)
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139 | {
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140 | byte* cBuf;
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141 | int qSz, pSz, cSz, err;
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142 | mp_int tmpQ;
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143 |
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144 | if (rng == NULL || dsa == NULL)
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145 | return BAD_FUNC_ARG;
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146 |
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147 | qSz = mp_unsigned_bin_size(&dsa->q);
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148 | pSz = mp_unsigned_bin_size(&dsa->p);
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149 |
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150 | /* verify (L,N) pair bit lengths */
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151 | if (CheckDsaLN(pSz * WOLFSSL_BIT_SIZE, qSz * WOLFSSL_BIT_SIZE) != 0)
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152 | return BAD_FUNC_ARG;
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153 |
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154 | /* generate extra 64 bits so that bias from mod function is negligible */
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155 | cSz = qSz + (64 / WOLFSSL_BIT_SIZE);
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156 | cBuf = (byte*)XMALLOC(cSz, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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157 | if (cBuf == NULL) {
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158 | return MEMORY_E;
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159 | }
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160 |
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161 | if ((err = mp_init_multi(&dsa->x, &dsa->y, &tmpQ, NULL, NULL, NULL))
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162 | != MP_OKAY) {
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163 | XFREE(cBuf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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164 | return err;
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165 | }
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166 |
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167 | do {
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168 | /* generate N+64 bits (c) from RBG into &dsa->x, making sure positive.
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169 | * Hash_DRBG uses SHA-256 which matches maximum
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170 | * requested_security_strength of (L,N) */
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171 | err = wc_RNG_GenerateBlock(rng, cBuf, cSz);
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172 | if (err != MP_OKAY) {
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173 | mp_clear(&dsa->x);
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174 | mp_clear(&dsa->y);
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175 | mp_clear(&tmpQ);
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176 | XFREE(cBuf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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177 | return err;
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178 | }
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179 |
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180 | err = mp_read_unsigned_bin(&dsa->x, cBuf, cSz);
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181 | if (err != MP_OKAY) {
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182 | mp_clear(&dsa->x);
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183 | mp_clear(&dsa->y);
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184 | mp_clear(&tmpQ);
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185 | XFREE(cBuf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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186 | return err;
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187 | }
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188 | } while (mp_cmp_d(&dsa->x, 1) != MP_GT);
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189 |
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190 | XFREE(cBuf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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191 |
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192 | /* tmpQ = q - 1 */
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193 | if (err == MP_OKAY)
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194 | err = mp_copy(&dsa->q, &tmpQ);
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195 |
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196 | if (err == MP_OKAY)
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197 | err = mp_sub_d(&tmpQ, 1, &tmpQ);
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198 |
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199 | /* x = c mod (q-1), &dsa->x holds c */
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200 | if (err == MP_OKAY)
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201 | err = mp_mod(&dsa->x, &tmpQ, &dsa->x);
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202 |
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203 | /* x = c mod (q-1) + 1 */
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204 | if (err == MP_OKAY)
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205 | err = mp_add_d(&dsa->x, 1, &dsa->x);
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206 |
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207 | /* public key : y = g^x mod p */
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208 | if (err == MP_OKAY)
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209 | err = mp_exptmod_ex(&dsa->g, &dsa->x, dsa->q.used, &dsa->p, &dsa->y);
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210 |
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211 | if (err == MP_OKAY)
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212 | dsa->type = DSA_PRIVATE;
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213 |
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214 | if (err != MP_OKAY) {
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215 | mp_clear(&dsa->x);
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216 | mp_clear(&dsa->y);
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217 | }
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218 | mp_clear(&tmpQ);
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219 |
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220 | return err;
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221 | }
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222 |
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223 |
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224 | /* modulus_size in bits */
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225 | int wc_MakeDsaParameters(WC_RNG *rng, int modulus_size, DsaKey *dsa)
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226 | {
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227 | mp_int tmp, tmp2;
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228 | int err, msize, qsize,
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229 | loop_check_prime = 0,
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230 | check_prime = MP_NO;
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231 | unsigned char *buf;
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232 |
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233 | if (rng == NULL || dsa == NULL)
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234 | return BAD_FUNC_ARG;
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235 |
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236 | /* set group size in bytes from modulus size
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237 | * FIPS 186-4 defines valid values (1024, 160) (2048, 256) (3072, 256)
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238 | */
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239 | switch (modulus_size) {
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240 | case 1024:
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241 | qsize = 20;
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242 | break;
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243 | case 2048:
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244 | case 3072:
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245 | qsize = 32;
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246 | break;
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247 | default:
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248 | return BAD_FUNC_ARG;
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249 | }
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250 |
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251 | /* modulus size in bytes */
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252 | msize = modulus_size / WOLFSSL_BIT_SIZE;
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253 |
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254 | /* allocate ram */
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255 | buf = (unsigned char *)XMALLOC(msize - qsize,
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256 | dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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257 | if (buf == NULL) {
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258 | return MEMORY_E;
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259 | }
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260 |
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261 | /* make a random string that will be multiplied against q */
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262 | err = wc_RNG_GenerateBlock(rng, buf, msize - qsize);
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263 | if (err != MP_OKAY) {
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264 | XFREE(buf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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265 | return err;
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266 | }
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267 |
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268 | /* force magnitude */
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269 | buf[0] |= 0xC0;
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270 |
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271 | /* force even */
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272 | buf[msize - qsize - 1] &= ~1;
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273 |
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274 | if (mp_init_multi(&tmp2, &dsa->p, &dsa->q, 0, 0, 0) != MP_OKAY) {
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275 | mp_clear(&dsa->q);
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276 | XFREE(buf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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277 | return MP_INIT_E;
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278 | }
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279 |
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280 | err = mp_read_unsigned_bin(&tmp2, buf, msize - qsize);
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281 | if (err != MP_OKAY) {
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282 | mp_clear(&dsa->q);
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283 | mp_clear(&dsa->p);
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284 | mp_clear(&tmp2);
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285 | XFREE(buf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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286 | return err;
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287 | }
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288 | XFREE(buf, dsa->heap, DYNAMIC_TYPE_TMP_BUFFER);
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289 |
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290 | /* make our prime q */
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291 | err = mp_rand_prime(&dsa->q, qsize, rng, NULL);
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292 | if (err != MP_OKAY) {
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293 | mp_clear(&dsa->q);
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294 | mp_clear(&dsa->p);
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295 | mp_clear(&tmp2);
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296 | return err;
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297 | }
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298 |
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299 | /* p = random * q */
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300 | err = mp_mul(&dsa->q, &tmp2, &dsa->p);
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301 | if (err != MP_OKAY) {
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302 | mp_clear(&dsa->q);
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303 | mp_clear(&dsa->p);
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304 | mp_clear(&tmp2);
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305 | return err;
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306 | }
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307 |
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308 | /* p = random * q + 1, so q is a prime divisor of p-1 */
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309 | err = mp_add_d(&dsa->p, 1, &dsa->p);
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310 | if (err != MP_OKAY) {
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311 | mp_clear(&dsa->q);
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312 | mp_clear(&dsa->p);
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313 | mp_clear(&tmp2);
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314 | return err;
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315 | }
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316 |
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317 | if (mp_init(&tmp) != MP_OKAY) {
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318 | mp_clear(&dsa->q);
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319 | mp_clear(&dsa->p);
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320 | mp_clear(&tmp2);
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321 | return MP_INIT_E;
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322 | }
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323 |
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324 | /* tmp = 2q */
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325 | err = mp_add(&dsa->q, &dsa->q, &tmp);
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326 | if (err != MP_OKAY) {
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327 | mp_clear(&dsa->q);
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328 | mp_clear(&dsa->p);
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329 | mp_clear(&tmp);
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330 | mp_clear(&tmp2);
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331 | return err;
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332 | }
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333 |
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334 | /* loop until p is prime */
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335 | while (check_prime == MP_NO) {
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336 | err = mp_prime_is_prime_ex(&dsa->p, 8, &check_prime, rng);
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337 | if (err != MP_OKAY) {
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338 | mp_clear(&dsa->q);
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339 | mp_clear(&dsa->p);
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340 | mp_clear(&tmp);
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341 | mp_clear(&tmp2);
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342 | return err;
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343 | }
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344 |
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345 | if (check_prime != MP_YES) {
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346 | /* p += 2q */
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347 | err = mp_add(&tmp, &dsa->p, &dsa->p);
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348 | if (err != MP_OKAY) {
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349 | mp_clear(&dsa->q);
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350 | mp_clear(&dsa->p);
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351 | mp_clear(&tmp);
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352 | mp_clear(&tmp2);
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353 | return err;
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354 | }
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355 |
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356 | loop_check_prime++;
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357 | }
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358 | }
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359 |
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360 | /* tmp2 += (2*loop_check_prime)
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361 | * to have p = (q * tmp2) + 1 prime
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362 | */
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363 | if (loop_check_prime) {
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364 | err = mp_add_d(&tmp2, 2*loop_check_prime, &tmp2);
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365 | if (err != MP_OKAY) {
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366 | mp_clear(&dsa->q);
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367 | mp_clear(&dsa->p);
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368 | mp_clear(&tmp);
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369 | mp_clear(&tmp2);
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370 | return err;
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371 | }
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372 | }
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373 |
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374 | if (mp_init(&dsa->g) != MP_OKAY) {
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375 | mp_clear(&dsa->q);
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376 | mp_clear(&dsa->p);
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377 | mp_clear(&tmp);
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378 | mp_clear(&tmp2);
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379 | return MP_INIT_E;
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380 | }
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381 |
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382 | /* find a value g for which g^tmp2 != 1 */
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383 | if (mp_set(&dsa->g, 1) != MP_OKAY) {
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384 | mp_clear(&dsa->q);
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385 | mp_clear(&dsa->p);
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386 | mp_clear(&tmp);
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387 | mp_clear(&tmp2);
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388 | return MP_INIT_E;
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389 | }
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390 |
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391 | do {
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392 | err = mp_add_d(&dsa->g, 1, &dsa->g);
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393 | if (err != MP_OKAY) {
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394 | mp_clear(&dsa->q);
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395 | mp_clear(&dsa->p);
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396 | mp_clear(&dsa->g);
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397 | mp_clear(&tmp);
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398 | mp_clear(&tmp2);
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399 | return err;
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400 | }
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401 |
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402 | err = mp_exptmod(&dsa->g, &tmp2, &dsa->p, &tmp);
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403 | if (err != MP_OKAY) {
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404 | mp_clear(&dsa->q);
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405 | mp_clear(&dsa->p);
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406 | mp_clear(&dsa->g);
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407 | mp_clear(&tmp);
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408 | mp_clear(&tmp2);
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409 | return err;
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410 | }
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411 |
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412 | } while (mp_cmp_d(&tmp, 1) == MP_EQ);
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413 |
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414 | /* at this point tmp generates a group of order q mod p */
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415 | #ifndef USE_FAST_MATH
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416 | /* Exchanging is quick when the data pointer can be copied. */
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417 | mp_exch(&tmp, &dsa->g);
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418 | #else
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419 | mp_copy(&tmp, &dsa->g);
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420 | #endif
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421 |
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422 | mp_clear(&tmp);
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423 | mp_clear(&tmp2);
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424 |
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425 | return MP_OKAY;
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426 | }
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427 | #endif /* WOLFSSL_KEY_GEN */
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428 |
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429 |
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430 | static int _DsaImportParamsRaw(DsaKey* dsa, const char* p, const char* q,
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431 | const char* g, int trusted, WC_RNG* rng)
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432 | {
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433 | int err;
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434 | word32 pSz, qSz;
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435 |
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436 | if (dsa == NULL || p == NULL || q == NULL || g == NULL)
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437 | return BAD_FUNC_ARG;
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438 |
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439 | /* read p */
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440 | err = mp_read_radix(&dsa->p, p, MP_RADIX_HEX);
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441 | if (err == MP_OKAY && !trusted) {
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442 | int isPrime = 1;
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443 | if (rng == NULL)
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444 | err = mp_prime_is_prime(&dsa->p, 8, &isPrime);
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445 | else
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446 | err = mp_prime_is_prime_ex(&dsa->p, 8, &isPrime, rng);
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447 |
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448 | if (err == MP_OKAY) {
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449 | if (!isPrime)
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450 | err = DH_CHECK_PUB_E;
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451 | }
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452 | }
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453 |
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454 | /* read q */
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455 | if (err == MP_OKAY)
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456 | err = mp_read_radix(&dsa->q, q, MP_RADIX_HEX);
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457 |
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458 | /* read g */
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459 | if (err == MP_OKAY)
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460 | err = mp_read_radix(&dsa->g, g, MP_RADIX_HEX);
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461 |
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462 | /* verify (L,N) pair bit lengths */
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463 | pSz = mp_unsigned_bin_size(&dsa->p);
|
---|
464 | qSz = mp_unsigned_bin_size(&dsa->q);
|
---|
465 |
|
---|
466 | if (CheckDsaLN(pSz * WOLFSSL_BIT_SIZE, qSz * WOLFSSL_BIT_SIZE) != 0) {
|
---|
467 | WOLFSSL_MSG("Invalid DSA p or q parameter size");
|
---|
468 | err = BAD_FUNC_ARG;
|
---|
469 | }
|
---|
470 |
|
---|
471 | if (err != MP_OKAY) {
|
---|
472 | mp_clear(&dsa->p);
|
---|
473 | mp_clear(&dsa->q);
|
---|
474 | mp_clear(&dsa->g);
|
---|
475 | }
|
---|
476 |
|
---|
477 | return err;
|
---|
478 | }
|
---|
479 |
|
---|
480 |
|
---|
481 | /* Import raw DSA parameters into DsaKey structure for use with wc_MakeDsaKey(),
|
---|
482 | * input parameters (p,q,g) should be represented as ASCII hex values.
|
---|
483 | *
|
---|
484 | * dsa - pointer to initialized DsaKey structure
|
---|
485 | * p - DSA (p) parameter, ASCII hex string
|
---|
486 | * pSz - length of p
|
---|
487 | * q - DSA (q) parameter, ASCII hex string
|
---|
488 | * qSz - length of q
|
---|
489 | * g - DSA (g) parameter, ASCII hex string
|
---|
490 | * gSz - length of g
|
---|
491 | *
|
---|
492 | * returns 0 on success, negative upon failure
|
---|
493 | */
|
---|
494 | int wc_DsaImportParamsRaw(DsaKey* dsa, const char* p, const char* q,
|
---|
495 | const char* g)
|
---|
496 | {
|
---|
497 | return _DsaImportParamsRaw(dsa, p, q, g, 1, NULL);
|
---|
498 | }
|
---|
499 |
|
---|
500 |
|
---|
501 | /* Import raw DSA parameters into DsaKey structure for use with wc_MakeDsaKey(),
|
---|
502 | * input parameters (p,q,g) should be represented as ASCII hex values. Check
|
---|
503 | * that the p value is probably prime.
|
---|
504 | *
|
---|
505 | * dsa - pointer to initialized DsaKey structure
|
---|
506 | * p - DSA (p) parameter, ASCII hex string
|
---|
507 | * pSz - length of p
|
---|
508 | * q - DSA (q) parameter, ASCII hex string
|
---|
509 | * qSz - length of q
|
---|
510 | * g - DSA (g) parameter, ASCII hex string
|
---|
511 | * gSz - length of g
|
---|
512 | * trusted - trust that p is OK
|
---|
513 | * rng - random number generator for the prime test
|
---|
514 | *
|
---|
515 | * returns 0 on success, negative upon failure
|
---|
516 | */
|
---|
517 | int wc_DsaImportParamsRawCheck(DsaKey* dsa, const char* p, const char* q,
|
---|
518 | const char* g, int trusted, WC_RNG* rng)
|
---|
519 | {
|
---|
520 | return _DsaImportParamsRaw(dsa, p, q, g, trusted, rng);
|
---|
521 | }
|
---|
522 |
|
---|
523 |
|
---|
524 | /* Export raw DSA parameters from DsaKey structure
|
---|
525 | *
|
---|
526 | * dsa - pointer to initialized DsaKey structure
|
---|
527 | * p - output location for DSA (p) parameter
|
---|
528 | * pSz - [IN/OUT] size of output buffer for p, size of p
|
---|
529 | * q - output location for DSA (q) parameter
|
---|
530 | * qSz - [IN/OUT] size of output buffer for q, size of q
|
---|
531 | * g - output location for DSA (g) parameter
|
---|
532 | * gSz - [IN/OUT] size of output buffer for g, size of g
|
---|
533 | *
|
---|
534 | * If p, q, and g pointers are all passed in as NULL, the function
|
---|
535 | * will set pSz, qSz, and gSz to the required output buffer sizes for p,
|
---|
536 | * q, and g. In this case, the function will return LENGTH_ONLY_E.
|
---|
537 | *
|
---|
538 | * returns 0 on success, negative upon failure
|
---|
539 | */
|
---|
540 | int wc_DsaExportParamsRaw(DsaKey* dsa, byte* p, word32* pSz,
|
---|
541 | byte* q, word32* qSz, byte* g, word32* gSz)
|
---|
542 | {
|
---|
543 | int err;
|
---|
544 | word32 pLen, qLen, gLen;
|
---|
545 |
|
---|
546 | if (dsa == NULL || pSz == NULL || qSz == NULL || gSz == NULL)
|
---|
547 | return BAD_FUNC_ARG;
|
---|
548 |
|
---|
549 | /* get required output buffer sizes */
|
---|
550 | pLen = mp_unsigned_bin_size(&dsa->p);
|
---|
551 | qLen = mp_unsigned_bin_size(&dsa->q);
|
---|
552 | gLen = mp_unsigned_bin_size(&dsa->g);
|
---|
553 |
|
---|
554 | /* return buffer sizes and LENGTH_ONLY_E if buffers are NULL */
|
---|
555 | if (p == NULL && q == NULL && g == NULL) {
|
---|
556 | *pSz = pLen;
|
---|
557 | *qSz = qLen;
|
---|
558 | *gSz = gLen;
|
---|
559 | return LENGTH_ONLY_E;
|
---|
560 | }
|
---|
561 |
|
---|
562 | if (p == NULL || q == NULL || g == NULL)
|
---|
563 | return BAD_FUNC_ARG;
|
---|
564 |
|
---|
565 | /* export p */
|
---|
566 | if (*pSz < pLen) {
|
---|
567 | WOLFSSL_MSG("Output buffer for DSA p parameter too small, "
|
---|
568 | "required size placed into pSz");
|
---|
569 | *pSz = pLen;
|
---|
570 | return BUFFER_E;
|
---|
571 | }
|
---|
572 | *pSz = pLen;
|
---|
573 | err = mp_to_unsigned_bin(&dsa->p, p);
|
---|
574 |
|
---|
575 | /* export q */
|
---|
576 | if (err == MP_OKAY) {
|
---|
577 | if (*qSz < qLen) {
|
---|
578 | WOLFSSL_MSG("Output buffer for DSA q parameter too small, "
|
---|
579 | "required size placed into qSz");
|
---|
580 | *qSz = qLen;
|
---|
581 | return BUFFER_E;
|
---|
582 | }
|
---|
583 | *qSz = qLen;
|
---|
584 | err = mp_to_unsigned_bin(&dsa->q, q);
|
---|
585 | }
|
---|
586 |
|
---|
587 | /* export g */
|
---|
588 | if (err == MP_OKAY) {
|
---|
589 | if (*gSz < gLen) {
|
---|
590 | WOLFSSL_MSG("Output buffer for DSA g parameter too small, "
|
---|
591 | "required size placed into gSz");
|
---|
592 | *gSz = gLen;
|
---|
593 | return BUFFER_E;
|
---|
594 | }
|
---|
595 | *gSz = gLen;
|
---|
596 | err = mp_to_unsigned_bin(&dsa->g, g);
|
---|
597 | }
|
---|
598 |
|
---|
599 | return err;
|
---|
600 | }
|
---|
601 |
|
---|
602 |
|
---|
603 | /* Export raw DSA key (x, y) from DsaKey structure
|
---|
604 | *
|
---|
605 | * dsa - pointer to initialized DsaKey structure
|
---|
606 | * x - output location for private key
|
---|
607 | * xSz - [IN/OUT] size of output buffer for x, size of x
|
---|
608 | * y - output location for public key
|
---|
609 | * ySz - [IN/OUT] size of output buffer for y, size of y
|
---|
610 | *
|
---|
611 | * If x and y pointers are all passed in as NULL, the function
|
---|
612 | * will set xSz and ySz to the required output buffer sizes for x
|
---|
613 | * and y. In this case, the function will return LENGTH_ONLY_E.
|
---|
614 | *
|
---|
615 | * returns 0 on success, negative upon failure
|
---|
616 | */
|
---|
617 | int wc_DsaExportKeyRaw(DsaKey* dsa, byte* x, word32* xSz, byte* y, word32* ySz)
|
---|
618 | {
|
---|
619 | int err;
|
---|
620 | word32 xLen, yLen;
|
---|
621 |
|
---|
622 | if (dsa == NULL || xSz == NULL || ySz == NULL)
|
---|
623 | return BAD_FUNC_ARG;
|
---|
624 |
|
---|
625 | /* get required output buffer sizes */
|
---|
626 | xLen = mp_unsigned_bin_size(&dsa->x);
|
---|
627 | yLen = mp_unsigned_bin_size(&dsa->y);
|
---|
628 |
|
---|
629 | /* return buffer sizes and LENGTH_ONLY_E if buffers are NULL */
|
---|
630 | if (x == NULL && y == NULL) {
|
---|
631 | *xSz = xLen;
|
---|
632 | *ySz = yLen;
|
---|
633 | return LENGTH_ONLY_E;
|
---|
634 | }
|
---|
635 |
|
---|
636 | if (x == NULL || y == NULL)
|
---|
637 | return BAD_FUNC_ARG;
|
---|
638 |
|
---|
639 | /* export x */
|
---|
640 | if (*xSz < xLen) {
|
---|
641 | WOLFSSL_MSG("Output buffer for DSA private key (x) too small, "
|
---|
642 | "required size placed into xSz");
|
---|
643 | *xSz = xLen;
|
---|
644 | return BUFFER_E;
|
---|
645 | }
|
---|
646 | *xSz = xLen;
|
---|
647 | err = mp_to_unsigned_bin(&dsa->x, x);
|
---|
648 |
|
---|
649 | /* export y */
|
---|
650 | if (err == MP_OKAY) {
|
---|
651 | if (*ySz < yLen) {
|
---|
652 | WOLFSSL_MSG("Output buffer to DSA public key (y) too small, "
|
---|
653 | "required size placed into ySz");
|
---|
654 | *ySz = yLen;
|
---|
655 | return BUFFER_E;
|
---|
656 | }
|
---|
657 | *ySz = yLen;
|
---|
658 | err = mp_to_unsigned_bin(&dsa->y, y);
|
---|
659 | }
|
---|
660 |
|
---|
661 | return err;
|
---|
662 | }
|
---|
663 |
|
---|
664 |
|
---|
665 | int wc_DsaSign(const byte* digest, byte* out, DsaKey* key, WC_RNG* rng)
|
---|
666 | {
|
---|
667 | #ifdef WOLFSSL_SMALL_STACK
|
---|
668 | mp_int *k = (mp_int *)XMALLOC(sizeof *k,
|
---|
669 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
670 | mp_int *kInv = (mp_int *)XMALLOC(sizeof *kInv,
|
---|
671 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
672 | mp_int *r = (mp_int *)XMALLOC(sizeof *r,
|
---|
673 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
674 | mp_int *s = (mp_int *)XMALLOC(sizeof *s,
|
---|
675 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
676 | mp_int *H = (mp_int *)XMALLOC(sizeof *H,
|
---|
677 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
678 | #ifndef WOLFSSL_MP_INVMOD_CONSTANT_TIME
|
---|
679 | mp_int *b = (mp_int *)XMALLOC(sizeof *b,
|
---|
680 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
681 | #endif
|
---|
682 | byte *buffer = (byte *)XMALLOC(DSA_HALF_SIZE, key->heap,
|
---|
683 | DYNAMIC_TYPE_TMP_BUFFER);
|
---|
684 | #else
|
---|
685 | mp_int k[1], kInv[1], r[1], s[1], H[1];
|
---|
686 | #ifndef WOLFSSL_MP_INVMOD_CONSTANT_TIME
|
---|
687 | mp_int b[1];
|
---|
688 | #endif
|
---|
689 | byte buffer[DSA_HALF_SIZE];
|
---|
690 | #endif
|
---|
691 | mp_int* qMinus1;
|
---|
692 | int ret = 0, sz = 0;
|
---|
693 | byte* tmp; /* initial output pointer */
|
---|
694 |
|
---|
695 | do {
|
---|
696 | #ifdef WOLFSSL_MP_INVMOD_CONSTANT_TIME
|
---|
697 | if (mp_init_multi(k, kInv, r, s, H, 0) != MP_OKAY)
|
---|
698 | #else
|
---|
699 | if (mp_init_multi(k, kInv, r, s, H, b) != MP_OKAY)
|
---|
700 | #endif
|
---|
701 | {
|
---|
702 | ret = MP_INIT_E;
|
---|
703 | break;
|
---|
704 | }
|
---|
705 |
|
---|
706 | #ifdef WOLFSSL_SMALL_STACK
|
---|
707 | if ((k == NULL) ||
|
---|
708 | (kInv == NULL) ||
|
---|
709 | (r == NULL) ||
|
---|
710 | (s == NULL) ||
|
---|
711 | (H == NULL)
|
---|
712 | #ifndef WOLFSSL_MP_INVMOD_CONSTANT_TIME
|
---|
713 | || (b == NULL)
|
---|
714 | #endif
|
---|
715 | || (buffer == NULL)) {
|
---|
716 | ret = MEMORY_E;
|
---|
717 | break;
|
---|
718 | }
|
---|
719 | #endif
|
---|
720 |
|
---|
721 | if (digest == NULL || out == NULL || key == NULL || rng == NULL) {
|
---|
722 | ret = BAD_FUNC_ARG;
|
---|
723 | break;
|
---|
724 | }
|
---|
725 |
|
---|
726 | sz = min(DSA_HALF_SIZE, mp_unsigned_bin_size(&key->q));
|
---|
727 | tmp = out;
|
---|
728 | qMinus1 = kInv;
|
---|
729 |
|
---|
730 | /* NIST FIPS 186-4: B.2.2
|
---|
731 | * Per-Message Secret Number Generation by Testing Candidates
|
---|
732 | * Generate k in range [1, q-1].
|
---|
733 | * Check that k is less than q-1: range [0, q-2].
|
---|
734 | * Add 1 to k: range [1, q-1].
|
---|
735 | */
|
---|
736 | if (mp_sub_d(&key->q, 1, qMinus1)) {
|
---|
737 | ret = MP_SUB_E;
|
---|
738 | break;
|
---|
739 | }
|
---|
740 |
|
---|
741 | do {
|
---|
742 | /* Step 4: generate k */
|
---|
743 | if ((ret = wc_RNG_GenerateBlock(rng, buffer, sz))) {
|
---|
744 | break;
|
---|
745 | }
|
---|
746 |
|
---|
747 | /* Step 5 */
|
---|
748 | if (mp_read_unsigned_bin(k, buffer, sz) != MP_OKAY) {
|
---|
749 | ret = MP_READ_E;
|
---|
750 | break;
|
---|
751 | }
|
---|
752 |
|
---|
753 | /* k is a random numnber and it should be less than q-1
|
---|
754 | * if k greater than repeat
|
---|
755 | */
|
---|
756 | /* Step 6 */
|
---|
757 | } while (mp_cmp(k, qMinus1) != MP_LT);
|
---|
758 |
|
---|
759 | if (ret != 0)
|
---|
760 | break;
|
---|
761 |
|
---|
762 | /* Step 7 */
|
---|
763 | if (mp_add_d(k, 1, k) != MP_OKAY) {
|
---|
764 | ret = MP_MOD_E;
|
---|
765 | break;
|
---|
766 | }
|
---|
767 |
|
---|
768 | #ifdef WOLFSSL_MP_INVMOD_CONSTANT_TIME
|
---|
769 | /* inverse k mod q */
|
---|
770 | if (mp_invmod(k, &key->q, kInv) != MP_OKAY) {
|
---|
771 | ret = MP_INVMOD_E;
|
---|
772 | break;
|
---|
773 | }
|
---|
774 |
|
---|
775 | /* generate r, r = (g exp k mod p) mod q */
|
---|
776 | if (mp_exptmod_ex(&key->g, k, key->q.used, &key->p, r) != MP_OKAY) {
|
---|
777 | ret = MP_EXPTMOD_E;
|
---|
778 | break;
|
---|
779 | }
|
---|
780 |
|
---|
781 | if (mp_mod(r, &key->q, r) != MP_OKAY) {
|
---|
782 | ret = MP_MOD_E;
|
---|
783 | break;
|
---|
784 | }
|
---|
785 |
|
---|
786 | /* generate H from sha digest */
|
---|
787 | if (mp_read_unsigned_bin(H, digest,WC_SHA_DIGEST_SIZE) != MP_OKAY) {
|
---|
788 | ret = MP_READ_E;
|
---|
789 | break;
|
---|
790 | }
|
---|
791 |
|
---|
792 | /* generate s, s = (kInv * (H + x*r)) % q */
|
---|
793 | if (mp_mul(&key->x, r, s) != MP_OKAY) {
|
---|
794 | ret = MP_MUL_E;
|
---|
795 | break;
|
---|
796 | }
|
---|
797 |
|
---|
798 | if (mp_add(s, H, s) != MP_OKAY) {
|
---|
799 | ret = MP_ADD_E;
|
---|
800 | break;
|
---|
801 | }
|
---|
802 |
|
---|
803 | if (mp_mulmod(s, kInv, &key->q, s) != MP_OKAY) {
|
---|
804 | ret = MP_MULMOD_E;
|
---|
805 | break;
|
---|
806 | }
|
---|
807 | #else
|
---|
808 | /* Blinding value
|
---|
809 | * Generate b in range [1, q-1].
|
---|
810 | */
|
---|
811 | do {
|
---|
812 | if ((ret = wc_RNG_GenerateBlock(rng, buffer, sz))) {
|
---|
813 | break;
|
---|
814 | }
|
---|
815 | if (mp_read_unsigned_bin(b, buffer, sz) != MP_OKAY) {
|
---|
816 | ret = MP_READ_E;
|
---|
817 | break;
|
---|
818 | }
|
---|
819 | } while (mp_cmp(b, qMinus1) != MP_LT);
|
---|
820 |
|
---|
821 | if (ret != 0)
|
---|
822 | break;
|
---|
823 |
|
---|
824 | if (mp_add_d(b, 1, b) != MP_OKAY) {
|
---|
825 | ret = MP_MOD_E;
|
---|
826 | break;
|
---|
827 | }
|
---|
828 |
|
---|
829 | /* set H from sha digest */
|
---|
830 | if (mp_read_unsigned_bin(H, digest, WC_SHA_DIGEST_SIZE) != MP_OKAY) {
|
---|
831 | ret = MP_READ_E;
|
---|
832 | break;
|
---|
833 | }
|
---|
834 |
|
---|
835 | /* generate r, r = (g exp k mod p) mod q */
|
---|
836 | if (mp_exptmod_ex(&key->g, k, key->q.used, &key->p, r) != MP_OKAY) {
|
---|
837 | ret = MP_EXPTMOD_E;
|
---|
838 | break;
|
---|
839 | }
|
---|
840 |
|
---|
841 | /* calculate s = (H + xr)/k = b.(H/k.b + x.r/k.b) */
|
---|
842 |
|
---|
843 | /* k = k.b */
|
---|
844 | if (mp_mulmod(k, b, &key->q, k) != MP_OKAY) {
|
---|
845 | ret = MP_MULMOD_E;
|
---|
846 | break;
|
---|
847 | }
|
---|
848 |
|
---|
849 | /* kInv = 1/k.b mod q */
|
---|
850 | if (mp_invmod(k, &key->q, kInv) != MP_OKAY) {
|
---|
851 | ret = MP_INVMOD_E;
|
---|
852 | break;
|
---|
853 | }
|
---|
854 |
|
---|
855 | if (mp_mod(r, &key->q, r) != MP_OKAY) {
|
---|
856 | ret = MP_MOD_E;
|
---|
857 | break;
|
---|
858 | }
|
---|
859 |
|
---|
860 | /* s = x.r */
|
---|
861 | if (mp_mul(&key->x, r, s) != MP_OKAY) {
|
---|
862 | ret = MP_MUL_E;
|
---|
863 | break;
|
---|
864 | }
|
---|
865 |
|
---|
866 | /* s = x.r/k.b */
|
---|
867 | if (mp_mulmod(s, kInv, &key->q, s) != MP_OKAY) {
|
---|
868 | ret = MP_MULMOD_E;
|
---|
869 | break;
|
---|
870 | }
|
---|
871 |
|
---|
872 | /* H = H/k.b */
|
---|
873 | if (mp_mulmod(H, kInv, &key->q, H) != MP_OKAY) {
|
---|
874 | ret = MP_MULMOD_E;
|
---|
875 | break;
|
---|
876 | }
|
---|
877 |
|
---|
878 | /* s = H/k.b + x.r/k.b = (H + x.r)/k.b */
|
---|
879 | if (mp_add(s, H, s) != MP_OKAY) {
|
---|
880 | ret = MP_ADD_E;
|
---|
881 | break;
|
---|
882 | }
|
---|
883 |
|
---|
884 | /* s = b.(e + x.r)/k.b = (e + x.r)/k */
|
---|
885 | if (mp_mulmod(s, b, &key->q, s) != MP_OKAY) {
|
---|
886 | ret = MP_MULMOD_E;
|
---|
887 | break;
|
---|
888 | }
|
---|
889 |
|
---|
890 | /* s = (e + x.r)/k */
|
---|
891 | if (mp_mod(s, &key->q, s) != MP_OKAY) {
|
---|
892 | ret = MP_MOD_E;
|
---|
893 | break;
|
---|
894 | }
|
---|
895 | #endif
|
---|
896 |
|
---|
897 | /* detect zero r or s */
|
---|
898 | if ((mp_iszero(r) == MP_YES) || (mp_iszero(s) == MP_YES)) {
|
---|
899 | ret = MP_ZERO_E;
|
---|
900 | break;
|
---|
901 | }
|
---|
902 |
|
---|
903 | /* write out */
|
---|
904 | {
|
---|
905 | int rSz = mp_unsigned_bin_size(r);
|
---|
906 | int sSz = mp_unsigned_bin_size(s);
|
---|
907 |
|
---|
908 | while (rSz++ < DSA_HALF_SIZE) {
|
---|
909 | *out++ = 0x00; /* pad front with zeros */
|
---|
910 | }
|
---|
911 |
|
---|
912 | if (mp_to_unsigned_bin(r, out) != MP_OKAY)
|
---|
913 | ret = MP_TO_E;
|
---|
914 | else {
|
---|
915 | out = tmp + DSA_HALF_SIZE; /* advance to s in output */
|
---|
916 | while (sSz++ < DSA_HALF_SIZE) {
|
---|
917 | *out++ = 0x00; /* pad front with zeros */
|
---|
918 | }
|
---|
919 | ret = mp_to_unsigned_bin(s, out);
|
---|
920 | }
|
---|
921 | }
|
---|
922 | } while (0);
|
---|
923 |
|
---|
924 | #ifdef WOLFSSL_SMALL_STACK
|
---|
925 | if (k) {
|
---|
926 | if (ret != MP_INIT_E)
|
---|
927 | mp_forcezero(k);
|
---|
928 | XFREE(k, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
929 | }
|
---|
930 | if (kInv) {
|
---|
931 | if (ret != MP_INIT_E)
|
---|
932 | mp_forcezero(kInv);
|
---|
933 | XFREE(kInv, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
934 | }
|
---|
935 | if (r) {
|
---|
936 | if (ret != MP_INIT_E)
|
---|
937 | mp_clear(r);
|
---|
938 | XFREE(r, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
939 | }
|
---|
940 | if (s) {
|
---|
941 | if (ret != MP_INIT_E)
|
---|
942 | mp_clear(s);
|
---|
943 | XFREE(s, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
944 | }
|
---|
945 | if (H) {
|
---|
946 | if (ret != MP_INIT_E)
|
---|
947 | mp_clear(H);
|
---|
948 | XFREE(H, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
949 | }
|
---|
950 | #ifndef WOLFSSL_MP_INVMOD_CONSTANT_TIME
|
---|
951 | if (b) {
|
---|
952 | if (ret != MP_INIT_E)
|
---|
953 | mp_forcezero(b);
|
---|
954 | XFREE(b, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
955 | }
|
---|
956 | #endif
|
---|
957 | if (buffer) {
|
---|
958 | ForceZero(buffer, sz);
|
---|
959 | XFREE(buffer, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
960 | }
|
---|
961 | #else /* !WOLFSSL_SMALL_STACK */
|
---|
962 | if (ret != MP_INIT_E) {
|
---|
963 | ForceZero(buffer, sz);
|
---|
964 | mp_forcezero(kInv);
|
---|
965 | mp_forcezero(k);
|
---|
966 | #ifndef WOLFSSL_MP_INVMOD_CONSTANT_TIME
|
---|
967 | mp_forcezero(b);
|
---|
968 | #endif
|
---|
969 | mp_clear(H);
|
---|
970 | mp_clear(s);
|
---|
971 | mp_clear(r);
|
---|
972 | }
|
---|
973 | #endif
|
---|
974 |
|
---|
975 | return ret;
|
---|
976 | }
|
---|
977 |
|
---|
978 |
|
---|
979 | int wc_DsaVerify(const byte* digest, const byte* sig, DsaKey* key, int* answer)
|
---|
980 | {
|
---|
981 | #ifdef WOLFSSL_SMALL_STACK
|
---|
982 | mp_int *w = (mp_int *)XMALLOC(sizeof *w,
|
---|
983 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
984 | mp_int *u1 = (mp_int *)XMALLOC(sizeof *u1,
|
---|
985 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
986 | mp_int *u2 = (mp_int *)XMALLOC(sizeof *u2,
|
---|
987 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
988 | mp_int *v = (mp_int *)XMALLOC(sizeof *v,
|
---|
989 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
990 | mp_int *r = (mp_int *)XMALLOC(sizeof *r,
|
---|
991 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
992 | mp_int *s = (mp_int *)XMALLOC(sizeof *s,
|
---|
993 | key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
994 | #else
|
---|
995 | mp_int w[1], u1[1], u2[1], v[1], r[1], s[1];
|
---|
996 | #endif
|
---|
997 | int ret = 0;
|
---|
998 |
|
---|
999 | do {
|
---|
1000 | if (mp_init_multi(w, u1, u2, v, r, s) != MP_OKAY) {
|
---|
1001 | ret = MP_INIT_E;
|
---|
1002 | break;
|
---|
1003 | }
|
---|
1004 |
|
---|
1005 | if (digest == NULL || sig == NULL || key == NULL || answer == NULL) {
|
---|
1006 | ret = BAD_FUNC_ARG;
|
---|
1007 | break;
|
---|
1008 | }
|
---|
1009 |
|
---|
1010 | #ifdef WOLFSSL_SMALL_STACK
|
---|
1011 | if ((w == NULL) ||
|
---|
1012 | (u1 == NULL) ||
|
---|
1013 | (u2 == NULL) ||
|
---|
1014 | (v == NULL) ||
|
---|
1015 | (r == NULL) ||
|
---|
1016 | (s == NULL)) {
|
---|
1017 | ret = MEMORY_E;
|
---|
1018 | break;
|
---|
1019 | }
|
---|
1020 | #endif
|
---|
1021 |
|
---|
1022 | /* set r and s from signature */
|
---|
1023 | if (mp_read_unsigned_bin(r, sig, DSA_HALF_SIZE) != MP_OKAY ||
|
---|
1024 | mp_read_unsigned_bin(s, sig + DSA_HALF_SIZE, DSA_HALF_SIZE) != MP_OKAY) {
|
---|
1025 | ret = MP_READ_E;
|
---|
1026 | break;
|
---|
1027 | }
|
---|
1028 |
|
---|
1029 | /* sanity checks */
|
---|
1030 | if (mp_iszero(r) == MP_YES || mp_iszero(s) == MP_YES ||
|
---|
1031 | mp_cmp(r, &key->q) != MP_LT || mp_cmp(s, &key->q) != MP_LT) {
|
---|
1032 | ret = MP_ZERO_E;
|
---|
1033 | break;
|
---|
1034 | }
|
---|
1035 |
|
---|
1036 | /* put H into u1 from sha digest */
|
---|
1037 | if (mp_read_unsigned_bin(u1,digest,WC_SHA_DIGEST_SIZE) != MP_OKAY) {
|
---|
1038 | ret = MP_READ_E;
|
---|
1039 | break;
|
---|
1040 | }
|
---|
1041 |
|
---|
1042 | /* w = s invmod q */
|
---|
1043 | if (mp_invmod(s, &key->q, w) != MP_OKAY) {
|
---|
1044 | ret = MP_INVMOD_E;
|
---|
1045 | break;
|
---|
1046 | }
|
---|
1047 |
|
---|
1048 | /* u1 = (H * w) % q */
|
---|
1049 | if (mp_mulmod(u1, w, &key->q, u1) != MP_OKAY) {
|
---|
1050 | ret = MP_MULMOD_E;
|
---|
1051 | break;
|
---|
1052 | }
|
---|
1053 |
|
---|
1054 | /* u2 = (r * w) % q */
|
---|
1055 | if (mp_mulmod(r, w, &key->q, u2) != MP_OKAY) {
|
---|
1056 | ret = MP_MULMOD_E;
|
---|
1057 | break;
|
---|
1058 | }
|
---|
1059 |
|
---|
1060 | /* verify v = ((g^u1 * y^u2) mod p) mod q */
|
---|
1061 | if (mp_exptmod(&key->g, u1, &key->p, u1) != MP_OKAY) {
|
---|
1062 | ret = MP_EXPTMOD_E;
|
---|
1063 | break;
|
---|
1064 | }
|
---|
1065 |
|
---|
1066 | if (mp_exptmod(&key->y, u2, &key->p, u2) != MP_OKAY) {
|
---|
1067 | ret = MP_EXPTMOD_E;
|
---|
1068 | break;
|
---|
1069 | }
|
---|
1070 |
|
---|
1071 | if (mp_mulmod(u1, u2, &key->p, v) != MP_OKAY) {
|
---|
1072 | ret = MP_MULMOD_E;
|
---|
1073 | break;
|
---|
1074 | }
|
---|
1075 |
|
---|
1076 | if (mp_mod(v, &key->q, v) != MP_OKAY) {
|
---|
1077 | ret = MP_MULMOD_E;
|
---|
1078 | break;
|
---|
1079 | }
|
---|
1080 |
|
---|
1081 | /* do they match */
|
---|
1082 | if (mp_cmp(r, v) == MP_EQ)
|
---|
1083 | *answer = 1;
|
---|
1084 | else
|
---|
1085 | *answer = 0;
|
---|
1086 | } while (0);
|
---|
1087 |
|
---|
1088 | #ifdef WOLFSSL_SMALL_STACK
|
---|
1089 | if (s) {
|
---|
1090 | if (ret != MP_INIT_E)
|
---|
1091 | mp_clear(s);
|
---|
1092 | XFREE(s, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
1093 | }
|
---|
1094 | if (r) {
|
---|
1095 | if (ret != MP_INIT_E)
|
---|
1096 | mp_clear(r);
|
---|
1097 | XFREE(r, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
1098 | }
|
---|
1099 | if (u1) {
|
---|
1100 | if (ret != MP_INIT_E)
|
---|
1101 | mp_clear(u1);
|
---|
1102 | XFREE(u1, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
1103 | }
|
---|
1104 | if (u2) {
|
---|
1105 | if (ret != MP_INIT_E)
|
---|
1106 | mp_clear(u2);
|
---|
1107 | XFREE(u2, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
1108 | }
|
---|
1109 | if (w) {
|
---|
1110 | if (ret != MP_INIT_E)
|
---|
1111 | mp_clear(w);
|
---|
1112 | XFREE(w, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
1113 | }
|
---|
1114 | if (v) {
|
---|
1115 | if (ret != MP_INIT_E)
|
---|
1116 | mp_clear(v);
|
---|
1117 | XFREE(v, key->heap, DYNAMIC_TYPE_TMP_BUFFER);
|
---|
1118 | }
|
---|
1119 | #else
|
---|
1120 | if (ret != MP_INIT_E) {
|
---|
1121 | mp_clear(s);
|
---|
1122 | mp_clear(r);
|
---|
1123 | mp_clear(u1);
|
---|
1124 | mp_clear(u2);
|
---|
1125 | mp_clear(w);
|
---|
1126 | mp_clear(v);
|
---|
1127 | }
|
---|
1128 | #endif
|
---|
1129 |
|
---|
1130 | return ret;
|
---|
1131 | }
|
---|
1132 |
|
---|
1133 |
|
---|
1134 | #endif /* NO_DSA */
|
---|
1135 |
|
---|