comparison: dav/crypto.c
dav/crypto.c
- changeset 5
- 88625853ae74
- child 9
- 6aec77cfa95b
equal
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| 4:ae5a98f0545c | 5:88625853ae74 |
|---|---|
| 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 | |
| 33 #include "crypto.h" | |
| 34 | |
| 35 AESDecrypter* aes_decrypter_new(Key *key, void *stream, dav_write_func write_func) { | |
| 36 AESDecrypter *dec = malloc(sizeof(AESDecrypter)); | |
| 37 dec->stream = stream; | |
| 38 dec->write = write_func; | |
| 39 | |
| 40 EVP_CIPHER_CTX_init(&dec->ctx); | |
| 41 if(key->type == KEY_AES128) { | |
| 42 EVP_DecryptInit_ex(&dec->ctx, EVP_aes_128_cbc(), NULL, key->data, NULL); | |
| 43 } else if(key->type == KEY_AES256) { | |
| 44 EVP_DecryptInit_ex(&dec->ctx, EVP_aes_256_cbc(), NULL, key->data, NULL); | |
| 45 } else { | |
| 46 fprintf(stderr, "unknown key type\n"); | |
| 47 exit(-1); | |
| 48 } | |
| 49 return dec; | |
| 50 } | |
| 51 | |
| 52 size_t aes_write(const void *buf, size_t s, size_t n, AESDecrypter *dec) { | |
| 53 int len = s*n; | |
| 54 int outlen = len + AES_BLOCK_SIZE; | |
| 55 unsigned char *out = malloc(outlen); | |
| 56 EVP_DecryptUpdate(&dec->ctx, out, &len, buf, len); | |
| 57 dec->write(out, 1, len, dec->stream); | |
| 58 free(out); | |
| 59 return (s*n) / s; | |
| 60 } | |
| 61 | |
| 62 void aes_decrypter_close(AESDecrypter *dec) { | |
| 63 void *out = malloc(128); | |
| 64 int len = 0; | |
| 65 EVP_DecryptFinal_ex(&dec->ctx, out, &len); | |
| 66 dec->write(out, 1, len, dec->stream); | |
| 67 free(out); | |
| 68 EVP_CIPHER_CTX_cleanup(&dec->ctx); | |
| 69 free(dec); | |
| 70 } | |
| 71 | |
| 72 | |
| 73 AESEncrypter* aes_encrypter_new(Key *key, void *stream, dav_read_func read_func) { | |
| 74 AESEncrypter *enc = malloc(sizeof(AESEncrypter)); | |
| 75 enc->stream = stream; | |
| 76 enc->read = read_func; | |
| 77 enc->tmp = NULL; | |
| 78 enc->tmplen = 0; | |
| 79 enc->tmpoff = 0; | |
| 80 enc->end = 0; | |
| 81 | |
| 82 EVP_CIPHER_CTX_init(&enc->ctx); | |
| 83 if(key->type == KEY_AES128) { | |
| 84 EVP_EncryptInit_ex(&enc->ctx, EVP_aes_128_cbc(), NULL, key->data, NULL); | |
| 85 } else if(key->type == KEY_AES256) { | |
| 86 EVP_EncryptInit_ex(&enc->ctx, EVP_aes_256_cbc(), NULL, key->data, NULL); | |
| 87 } else { | |
| 88 fprintf(stderr, "unknown key type\n"); | |
| 89 exit(-1); | |
| 90 } | |
| 91 return enc; | |
| 92 } | |
| 93 | |
| 94 size_t aes_read(void *buf, size_t s, size_t n, AESEncrypter *enc) { | |
| 95 size_t len = s*n; | |
| 96 if(enc->tmp) { | |
| 97 size_t tmp_diff = enc->tmplen - enc->tmpoff; | |
| 98 size_t cp_len = tmp_diff > len ? len : tmp_diff; | |
| 99 memcpy(buf, enc->tmp + enc->tmpoff, cp_len); | |
| 100 enc->tmpoff += cp_len; | |
| 101 if(enc->tmpoff >= enc->tmplen) { | |
| 102 free(enc->tmp); | |
| 103 enc->tmp = NULL; | |
| 104 enc->tmplen = 0; | |
| 105 enc->tmpoff = 0; | |
| 106 } | |
| 107 return cp_len / s; | |
| 108 } | |
| 109 | |
| 110 if(enc->end) { | |
| 111 return 0; | |
| 112 } | |
| 113 | |
| 114 void *in = malloc(len); | |
| 115 size_t in_len = enc->read(in, 1, len, enc->stream); | |
| 116 | |
| 117 void *out = NULL; | |
| 118 int outlen = 0; | |
| 119 if(in_len != 0) { | |
| 120 outlen = len + AES_BLOCK_SIZE; | |
| 121 out = malloc(outlen); | |
| 122 EVP_EncryptUpdate(&enc->ctx, out, &outlen, in, in_len); | |
| 123 //out = (char*)aes_encrypt(enc->ctx, (unsigned char*)in, (int*)&in_len); | |
| 124 } else { | |
| 125 out = malloc(AES_BLOCK_SIZE); | |
| 126 EVP_EncryptFinal_ex(&enc->ctx, out, &outlen); | |
| 127 enc->end = 1; | |
| 128 } | |
| 129 enc->tmp = out; | |
| 130 enc->tmplen = outlen; | |
| 131 enc->tmpoff = 0; | |
| 132 | |
| 133 return aes_read(buf, s, n, enc); | |
| 134 } | |
| 135 | |
| 136 void aes_encrypter_close(AESEncrypter *enc) { | |
| 137 if(enc->tmp) { | |
| 138 free(enc->tmp); | |
| 139 } | |
| 140 EVP_CIPHER_CTX_cleanup(&enc->ctx); | |
| 141 free(enc); | |
| 142 } |
