diff options
Diffstat (limited to 'src/lib/libcrypto/aes/aes_ctr.c')
| -rw-r--r-- | src/lib/libcrypto/aes/aes_ctr.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/src/lib/libcrypto/aes/aes_ctr.c b/src/lib/libcrypto/aes/aes_ctr.c new file mode 100644 index 0000000000..aea3db2092 --- /dev/null +++ b/src/lib/libcrypto/aes/aes_ctr.c | |||
| @@ -0,0 +1,117 @@ | |||
| 1 | /* crypto/aes/aes_ctr.c -*- mode:C; c-file-style: "eay" -*- */ | ||
| 2 | /* ==================================================================== | ||
| 3 | * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved. | ||
| 4 | * | ||
| 5 | * Redistribution and use in source and binary forms, with or without | ||
| 6 | * modification, are permitted provided that the following conditions | ||
| 7 | * 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 | ||
| 14 | * the documentation and/or other materials provided with the | ||
| 15 | * distribution. | ||
| 16 | * | ||
| 17 | * 3. All advertising materials mentioning features or use of this | ||
| 18 | * software must display the following acknowledgment: | ||
| 19 | * "This product includes software developed by the OpenSSL Project | ||
| 20 | * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" | ||
| 21 | * | ||
| 22 | * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to | ||
| 23 | * endorse or promote products derived from this software without | ||
| 24 | * prior written permission. For written permission, please contact | ||
| 25 | * openssl-core@openssl.org. | ||
| 26 | * | ||
| 27 | * 5. Products derived from this software may not be called "OpenSSL" | ||
| 28 | * nor may "OpenSSL" appear in their names without prior written | ||
| 29 | * permission of the OpenSSL Project. | ||
| 30 | * | ||
| 31 | * 6. Redistributions of any form whatsoever must retain the following | ||
| 32 | * acknowledgment: | ||
| 33 | * "This product includes software developed by the OpenSSL Project | ||
| 34 | * for use in the OpenSSL Toolkit (http://www.openssl.org/)" | ||
| 35 | * | ||
| 36 | * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY | ||
| 37 | * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
| 38 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | ||
| 39 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR | ||
| 40 | * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | ||
| 41 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | ||
| 42 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | ||
| 43 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | ||
| 44 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | ||
| 45 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | ||
| 46 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED | ||
| 47 | * OF THE POSSIBILITY OF SUCH DAMAGE. | ||
| 48 | * ==================================================================== | ||
| 49 | * | ||
| 50 | */ | ||
| 51 | |||
| 52 | #include <assert.h> | ||
| 53 | #include <openssl/aes.h> | ||
| 54 | #include "aes_locl.h" | ||
| 55 | |||
| 56 | /* NOTE: CTR mode is big-endian. The rest of the AES code | ||
| 57 | * is endian-neutral. */ | ||
| 58 | |||
| 59 | /* increment counter (128-bit int) by 2^64 */ | ||
| 60 | static void AES_ctr128_inc(unsigned char *counter) { | ||
| 61 | unsigned long c; | ||
| 62 | |||
| 63 | /* Grab 3rd dword of counter and increment */ | ||
| 64 | #ifdef L_ENDIAN | ||
| 65 | c = GETU32(counter + 8); | ||
| 66 | c++; | ||
| 67 | PUTU32(counter + 8, c); | ||
| 68 | #else | ||
| 69 | c = GETU32(counter + 4); | ||
| 70 | c++; | ||
| 71 | PUTU32(counter + 4, c); | ||
| 72 | #endif | ||
| 73 | |||
| 74 | /* if no overflow, we're done */ | ||
| 75 | if (c) | ||
| 76 | return; | ||
| 77 | |||
| 78 | /* Grab top dword of counter and increment */ | ||
| 79 | #ifdef L_ENDIAN | ||
| 80 | c = GETU32(counter + 12); | ||
| 81 | c++; | ||
| 82 | PUTU32(counter + 12, c); | ||
| 83 | #else | ||
| 84 | c = GETU32(counter + 0); | ||
| 85 | c++; | ||
| 86 | PUTU32(counter + 0, c); | ||
| 87 | #endif | ||
| 88 | |||
| 89 | } | ||
| 90 | |||
| 91 | /* The input encrypted as though 128bit counter mode is being | ||
| 92 | * used. The extra state information to record how much of the | ||
| 93 | * 128bit block we have used is contained in *num; | ||
| 94 | */ | ||
| 95 | void AES_ctr128_encrypt(const unsigned char *in, unsigned char *out, | ||
| 96 | const unsigned long length, const AES_KEY *key, | ||
| 97 | unsigned char *counter, unsigned int *num) { | ||
| 98 | |||
| 99 | unsigned int n; | ||
| 100 | unsigned long l=length; | ||
| 101 | unsigned char tmp[AES_BLOCK_SIZE]; | ||
| 102 | |||
| 103 | assert(in && out && key && counter && num); | ||
| 104 | |||
| 105 | n = *num; | ||
| 106 | |||
| 107 | while (l--) { | ||
| 108 | if (n == 0) { | ||
| 109 | AES_encrypt(counter, tmp, key); | ||
| 110 | AES_ctr128_inc(counter); | ||
| 111 | } | ||
| 112 | *(out++) = *(in++) ^ tmp[n]; | ||
| 113 | n = (n+1) % AES_BLOCK_SIZE; | ||
| 114 | } | ||
| 115 | |||
| 116 | *num=n; | ||
| 117 | } | ||
