8a24546c85
char * FooFileChunk(const char *filename, char *buf, off_t offset, off_t length) Which only hashes part of a file. Implement FooFile() in terms of this function. Submitted by: roam
209 lines
6.5 KiB
C
209 lines
6.5 KiB
C
/* MD2C.C - RSA Data Security, Inc., MD2 message-digest algorithm
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
/* Copyright (C) 1990-2, RSA Data Security, Inc. Created 1990. All
|
|
rights reserved.
|
|
|
|
License to copy and use this software is granted for
|
|
non-commercial Internet Privacy-Enhanced Mail provided that it is
|
|
identified as the "RSA Data Security, Inc. MD2 Message Digest
|
|
Algorithm" in all material mentioning or referencing this software
|
|
or this function.
|
|
|
|
RSA Data Security, Inc. makes no representations concerning either
|
|
the merchantability of this software or the suitability of this
|
|
software for any particular purpose. It is provided "as is"
|
|
without express or implied warranty of any kind.
|
|
|
|
These notices must be retained in any copies of any part of this
|
|
documentation and/or software.
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
#include <string.h>
|
|
#include "md2.h"
|
|
|
|
|
|
typedef unsigned char *POINTER;
|
|
typedef u_int16_t UINT2;
|
|
typedef u_int32_t UINT4;
|
|
|
|
#define PROTO_LIST(list) list
|
|
|
|
static void MD2Transform PROTO_LIST
|
|
((unsigned char [16], unsigned char [16], const unsigned char [16]));
|
|
|
|
/* Permutation of 0..255 constructed from the digits of pi. It gives a
|
|
"random" nonlinear byte substitution operation.
|
|
*/
|
|
static unsigned char PI_SUBST[256] = {
|
|
41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
|
|
19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
|
|
76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
|
|
138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
|
|
245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
|
|
148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
|
|
39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
|
|
181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
|
|
150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
|
|
112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
|
|
96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
|
|
85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
|
|
234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
|
|
129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
|
|
8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
|
|
203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
|
|
166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
|
|
31, 26, 219, 153, 141, 51, 159, 17, 131, 20
|
|
};
|
|
|
|
static unsigned char *PADDING[] = {
|
|
(unsigned char *)"",
|
|
(unsigned char *)"\001",
|
|
(unsigned char *)"\002\002",
|
|
(unsigned char *)"\003\003\003",
|
|
(unsigned char *)"\004\004\004\004",
|
|
(unsigned char *)"\005\005\005\005\005",
|
|
(unsigned char *)"\006\006\006\006\006\006",
|
|
(unsigned char *)"\007\007\007\007\007\007\007",
|
|
(unsigned char *)"\010\010\010\010\010\010\010\010",
|
|
(unsigned char *)"\011\011\011\011\011\011\011\011\011",
|
|
(unsigned char *)"\012\012\012\012\012\012\012\012\012\012",
|
|
(unsigned char *)"\013\013\013\013\013\013\013\013\013\013\013",
|
|
(unsigned char *)"\014\014\014\014\014\014\014\014\014\014\014\014",
|
|
(unsigned char *)
|
|
"\015\015\015\015\015\015\015\015\015\015\015\015\015",
|
|
(unsigned char *)
|
|
"\016\016\016\016\016\016\016\016\016\016\016\016\016\016",
|
|
(unsigned char *)
|
|
"\017\017\017\017\017\017\017\017\017\017\017\017\017\017\017",
|
|
(unsigned char *)
|
|
"\020\020\020\020\020\020\020\020\020\020\020\020\020\020\020\020"
|
|
};
|
|
|
|
/* MD2 initialization. Begins an MD2 operation, writing a new context.
|
|
*/
|
|
void MD2Init (context)
|
|
MD2_CTX *context; /* context */
|
|
{
|
|
context->count = 0;
|
|
memset ((POINTER)context->state, 0, sizeof (context->state));
|
|
memset
|
|
((POINTER)context->checksum, 0, sizeof (context->checksum));
|
|
}
|
|
|
|
/* MD2 block update operation. Continues an MD2 message-digest
|
|
operation, processing another message block, and updating the
|
|
context.
|
|
*/
|
|
void MD2Update (context, input, inputLen)
|
|
MD2_CTX *context; /* context */
|
|
const unsigned char *input; /* input block */
|
|
unsigned int inputLen; /* length of input block */
|
|
{
|
|
unsigned int i, index, partLen;
|
|
|
|
/* Update number of bytes mod 16 */
|
|
index = context->count;
|
|
context->count = (index + inputLen) & 0xf;
|
|
|
|
partLen = 16 - index;
|
|
|
|
/* Transform as many times as possible.
|
|
*/
|
|
if (inputLen >= partLen) {
|
|
memcpy
|
|
((POINTER)&context->buffer[index], (POINTER)input, partLen);
|
|
MD2Transform (context->state, context->checksum, context->buffer);
|
|
|
|
for (i = partLen; i + 15 < inputLen; i += 16)
|
|
MD2Transform (context->state, context->checksum, &input[i]);
|
|
|
|
index = 0;
|
|
}
|
|
else
|
|
i = 0;
|
|
|
|
/* Buffer remaining input */
|
|
memcpy
|
|
((POINTER)&context->buffer[index], (POINTER)&input[i],
|
|
inputLen-i);
|
|
}
|
|
|
|
/* MD2 padding.
|
|
*/
|
|
void MD2Pad (context)
|
|
MD2_CTX *context; /* context */
|
|
{
|
|
unsigned int index, padLen;
|
|
|
|
/* Pad out to multiple of 16.
|
|
*/
|
|
index = context->count;
|
|
padLen = 16 - index;
|
|
MD2Update (context, PADDING[padLen], padLen);
|
|
|
|
/* Extend with checksum */
|
|
MD2Update (context, context->checksum, 16);
|
|
}
|
|
|
|
/* MD2 finalization. Ends an MD2 message-digest operation, writing the
|
|
message digest and zeroizing the context.
|
|
*/
|
|
void MD2Final (digest, context)
|
|
unsigned char digest[16]; /* message digest */
|
|
MD2_CTX *context; /* context */
|
|
{
|
|
/* Do padding */
|
|
MD2Pad (context);
|
|
|
|
/* Store state in digest */
|
|
memcpy ((POINTER)digest, (POINTER)context->state, 16);
|
|
|
|
/* Zeroize sensitive information.
|
|
*/
|
|
memset ((POINTER)context, 0, sizeof (*context));
|
|
}
|
|
|
|
/* MD2 basic transformation. Transforms state and updates checksum
|
|
based on block.
|
|
*/
|
|
static void MD2Transform (state, checksum, block)
|
|
unsigned char state[16];
|
|
unsigned char checksum[16];
|
|
const unsigned char block[16];
|
|
{
|
|
unsigned int i, j, t;
|
|
unsigned char x[48];
|
|
|
|
/* Form encryption block from state, block, state ^ block.
|
|
*/
|
|
memcpy ((POINTER)x, (POINTER)state, 16);
|
|
memcpy ((POINTER)x+16, (POINTER)block, 16);
|
|
for (i = 0; i < 16; i++)
|
|
x[i+32] = state[i] ^ block[i];
|
|
|
|
/* Encrypt block (18 rounds).
|
|
*/
|
|
t = 0;
|
|
for (i = 0; i < 18; i++) {
|
|
for (j = 0; j < 48; j++)
|
|
t = x[j] ^= PI_SUBST[t];
|
|
t = (t + i) & 0xff;
|
|
}
|
|
|
|
/* Save new state */
|
|
memcpy ((POINTER)state, (POINTER)x, 16);
|
|
|
|
/* Update checksum.
|
|
*/
|
|
t = checksum[15];
|
|
for (i = 0; i < 16; i++)
|
|
t = checksum[i] ^= PI_SUBST[block[i] ^ t];
|
|
|
|
/* Zeroize sensitive information.
|
|
*/
|
|
memset ((POINTER)x, 0, sizeof (x));
|
|
}
|