comparison: dav/crypto.c
dav/crypto.c
- changeset 40
- a95ee94b9204
- parent 39
- 3e55bed345f9
- child 41
- 1c598ee0d3d9
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| 39:3e55bed345f9 | 40:a95ee94b9204 |
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| 1 /* | |
| 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. | |
| 3 * | |
| 4 * Copyright 2013 Olaf Wintermann. All rights reserved. | |
| 5 * | |
| 6 * Redistribution and use in source and binary forms, with or without | |
| 7 * modification, are permitted provided that the following conditions are met: | |
| 8 * | |
| 9 * 1. Redistributions of source code must retain the above copyright | |
| 10 * notice, this list of conditions and the following disclaimer. | |
| 11 * | |
| 12 * 2. Redistributions in binary form must reproduce the above copyright | |
| 13 * notice, this list of conditions and the following disclaimer in the | |
| 14 * documentation and/or other materials provided with the distribution. | |
| 15 * | |
| 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
| 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE | |
| 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
| 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
| 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
| 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
| 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
| 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
| 26 * POSSIBILITY OF SUCH DAMAGE. | |
| 27 */ | |
| 28 | |
| 29 #include <stdio.h> | |
| 30 #include <stdlib.h> | |
| 31 #include <string.h> | |
| 32 #include <openssl/rand.h> | |
| 33 | |
| 34 #include <libidav/utils.h> | |
| 35 #include "crypto.h" | |
| 36 | |
| 37 AESDecrypter* aes_decrypter_new(Key *key, void *stream, dav_write_func write_func) { | |
| 38 AESDecrypter *dec = malloc(sizeof(AESDecrypter)); | |
| 39 dec->stream = stream; | |
| 40 dec->write = write_func; | |
| 41 dec->key = key; | |
| 42 dec->init = 0; | |
| 43 dec->ivpos = 0; | |
| 44 | |
| 45 return dec; | |
| 46 } | |
| 47 | |
| 48 void aes_decrypter_init(AESDecrypter *dec) { | |
| 49 EVP_CIPHER_CTX_init(&dec->ctx); | |
| 50 dec->init = 1; | |
| 51 if(dec->key->type == KEY_AES128) { | |
| 52 EVP_DecryptInit_ex( | |
| 53 &dec->ctx, | |
| 54 EVP_aes_128_cbc(), | |
| 55 NULL, | |
| 56 dec->key->data, | |
| 57 dec->ivtmp); | |
| 58 } else if(dec->key->type == KEY_AES256) { | |
| 59 EVP_DecryptInit_ex( | |
| 60 &dec->ctx, | |
| 61 EVP_aes_256_cbc(), | |
| 62 NULL, | |
| 63 dec->key->data, | |
| 64 dec->ivtmp); | |
| 65 } else { | |
| 66 fprintf(stderr, "unknown key type\n"); | |
| 67 exit(-1); | |
| 68 } | |
| 69 } | |
| 70 | |
| 71 size_t aes_write(const void *buf, size_t s, size_t n, AESDecrypter *dec) { | |
| 72 int len = s*n; | |
| 73 if(!dec->init) { | |
| 74 size_t n = 16 - dec->ivpos; | |
| 75 size_t cp = n > len ? len : n; | |
| 76 memcpy(dec->ivtmp + dec->ivpos, buf, cp); | |
| 77 dec->ivpos += cp; | |
| 78 if(dec->ivpos >= 16) { | |
| 79 aes_decrypter_init(dec); | |
| 80 } | |
| 81 if(len == cp) { | |
| 82 return len; | |
| 83 } else { | |
| 84 buf = (char*)buf + cp; | |
| 85 len -= cp; | |
| 86 } | |
| 87 } | |
| 88 | |
| 89 int outlen = len + 16; | |
| 90 unsigned char *out = malloc(outlen); | |
| 91 EVP_DecryptUpdate(&dec->ctx, out, &len, buf, len); | |
| 92 dec->write(out, 1, len, dec->stream); | |
| 93 free(out); | |
| 94 return (s*n) / s; | |
| 95 } | |
| 96 | |
| 97 void aes_decrypter_close(AESDecrypter *dec) { | |
| 98 void *out = malloc(128); | |
| 99 int len = 0; | |
| 100 EVP_DecryptFinal_ex(&dec->ctx, out, &len); | |
| 101 dec->write(out, 1, len, dec->stream); | |
| 102 free(out); | |
| 103 EVP_CIPHER_CTX_cleanup(&dec->ctx); | |
| 104 free(dec); | |
| 105 } | |
| 106 | |
| 107 | |
| 108 AESEncrypter* aes_encrypter_new(Key *key, void *stream, dav_read_func read_func) { | |
| 109 unsigned char *iv = malloc(16); | |
| 110 if(!RAND_bytes(iv, 16)) { | |
| 111 free(iv); | |
| 112 return NULL; | |
| 113 } | |
| 114 | |
| 115 AESEncrypter *enc = malloc(sizeof(AESEncrypter)); | |
| 116 enc->stream = stream; | |
| 117 enc->read = read_func; | |
| 118 enc->tmp = NULL; | |
| 119 enc->tmplen = 0; | |
| 120 enc->tmpoff = 0; | |
| 121 enc->end = 0; | |
| 122 //enc->iv = iv; | |
| 123 enc->iv = iv; | |
| 124 enc->ivlen = 16; | |
| 125 | |
| 126 EVP_CIPHER_CTX_init(&enc->ctx); | |
| 127 if(key->type == KEY_AES128) { | |
| 128 EVP_EncryptInit_ex(&enc->ctx, EVP_aes_128_cbc(), NULL, key->data, enc->iv); | |
| 129 } else if(key->type == KEY_AES256) { | |
| 130 EVP_EncryptInit_ex(&enc->ctx, EVP_aes_256_cbc(), NULL, key->data, enc->iv); | |
| 131 } else { | |
| 132 fprintf(stderr, "unknown key type\n"); | |
| 133 exit(-1); | |
| 134 } | |
| 135 return enc; | |
| 136 } | |
| 137 | |
| 138 size_t aes_read(void *buf, size_t s, size_t n, AESEncrypter *enc) { | |
| 139 size_t len = s*n; | |
| 140 if(enc->tmp) { | |
| 141 size_t tmp_diff = enc->tmplen - enc->tmpoff; | |
| 142 size_t cp_len = tmp_diff > len ? len : tmp_diff; | |
| 143 memcpy(buf, enc->tmp + enc->tmpoff, cp_len); | |
| 144 enc->tmpoff += cp_len; | |
| 145 if(enc->tmpoff >= enc->tmplen) { | |
| 146 free(enc->tmp); | |
| 147 enc->tmp = NULL; | |
| 148 enc->tmplen = 0; | |
| 149 enc->tmpoff = 0; | |
| 150 } | |
| 151 return cp_len / s; | |
| 152 } | |
| 153 | |
| 154 if(enc->end) { | |
| 155 return 0; | |
| 156 } | |
| 157 | |
| 158 void *in = malloc(len); | |
| 159 size_t in_len = enc->read(in, 1, len, enc->stream); | |
| 160 | |
| 161 unsigned char *out = NULL; | |
| 162 int outlen = 0; | |
| 163 size_t ivl = enc->ivlen; | |
| 164 if(in_len != 0) { | |
| 165 outlen = len + 16; | |
| 166 out = malloc(outlen + ivl); | |
| 167 if(enc->iv) { | |
| 168 memcpy(out, enc->iv, ivl); | |
| 169 } | |
| 170 EVP_EncryptUpdate(&enc->ctx, out + ivl, &outlen, in, in_len); | |
| 171 free(in); | |
| 172 } else { | |
| 173 out = malloc(16); | |
| 174 EVP_EncryptFinal_ex(&enc->ctx, out, &outlen); | |
| 175 enc->end = 1; | |
| 176 } | |
| 177 enc->tmp = (char*)out; | |
| 178 enc->tmplen = outlen + ivl; | |
| 179 enc->tmpoff = 0; | |
| 180 | |
| 181 if(enc->iv) { | |
| 182 enc->iv = NULL; | |
| 183 enc->ivlen = 0; | |
| 184 } | |
| 185 | |
| 186 return aes_read(buf, s, n, enc); | |
| 187 } | |
| 188 | |
| 189 void aes_encrypter_close(AESEncrypter *enc) { | |
| 190 if(enc->tmp) { | |
| 191 free(enc->tmp); | |
| 192 } | |
| 193 EVP_CIPHER_CTX_cleanup(&enc->ctx); | |
| 194 free(enc); | |
| 195 } | |
| 196 | |
| 197 | |
| 198 char* aes_encrypt(char *in, Key *key) { | |
| 199 char *iv = malloc(16); | |
| 200 if(!RAND_bytes(iv, 16)) { | |
| 201 free(iv); | |
| 202 return NULL; | |
| 203 } | |
| 204 | |
| 205 EVP_CIPHER_CTX ctx; | |
| 206 EVP_CIPHER_CTX_init(&ctx); | |
| 207 if(key->type == KEY_AES128) { | |
| 208 EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, key->data, iv); | |
| 209 } else if(key->type == KEY_AES256) { | |
| 210 EVP_EncryptInit_ex(&ctx, EVP_aes_256_cbc(), NULL, key->data, iv); | |
| 211 } else { | |
| 212 return NULL; | |
| 213 } | |
| 214 | |
| 215 int len = strlen(in); | |
| 216 int buflen = len + 64; | |
| 217 char *buf = calloc(1, buflen); | |
| 218 memcpy(buf, iv, 16); | |
| 219 | |
| 220 int l = buflen - 16; | |
| 221 EVP_EncryptUpdate(&ctx, buf + 16, &l, in, len); | |
| 222 | |
| 223 int f = 0; | |
| 224 EVP_EncryptFinal_ex(&ctx, buf + 16 + l, &f); | |
| 225 char *out = util_base64encode(buf, 16 + l + f); | |
| 226 free(buf); | |
| 227 return out; | |
| 228 } | |
| 229 | |
| 230 char* aes_decrypt(char *in, Key *key) { | |
| 231 int len; | |
| 232 char *buf = util_base64decode_len(in, &len); | |
| 233 | |
| 234 EVP_CIPHER_CTX ctx; | |
| 235 EVP_CIPHER_CTX_init(&ctx); | |
| 236 if(key->type == KEY_AES128) { | |
| 237 EVP_DecryptInit_ex( | |
| 238 &ctx, | |
| 239 EVP_aes_128_cbc(), | |
| 240 NULL, | |
| 241 key->data, | |
| 242 buf); | |
| 243 } else if(key->type == KEY_AES256) { | |
| 244 EVP_DecryptInit_ex( | |
| 245 &ctx, | |
| 246 EVP_aes_256_cbc(), | |
| 247 NULL, | |
| 248 key->data, | |
| 249 buf); | |
| 250 } else { | |
| 251 return NULL; | |
| 252 } | |
| 253 | |
| 254 char *out = malloc(len + 1); | |
| 255 int outlen = len; | |
| 256 char *in_buf = buf + 16; | |
| 257 int inlen = len - 16; | |
| 258 int f = 0; | |
| 259 | |
| 260 | |
| 261 | |
| 262 EVP_DecryptUpdate(&ctx, out, &outlen, in_buf, inlen); | |
| 263 EVP_DecryptFinal_ex(&ctx, out + outlen, &f); | |
| 264 out[outlen + f] = '\0'; | |
| 265 free(buf); | |
| 266 return out; | |
| 267 } | |
| 268 |
