Feat: add reference implementation as 4

This commit is contained in:
Dorian Zedler 2022-07-20 13:22:49 +02:00
parent ee94b144b5
commit d4ef916b40
Signed by: dorian
GPG key ID: 989DE36109AFA354
9 changed files with 181 additions and 369 deletions

View file

@ -13,7 +13,8 @@
"array": "c",
"md2.h": "c",
"io.h": "c",
"md2_0.h": "c"
"md2_0.h": "c",
"md2_common.h": "c"
},
"editor.formatOnSave": true,
"C_Cpp.default.includePath": [

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@ -1,11 +1,11 @@
SRC = src/main.c src/helper.c src/io.c src/md2.c src/md2_impls/md2_common.c src/md2_impls/md2_0.c src/md2_impls/md2_1.c src/md2_impls/md2_2.c src/md2_impls/md2_3.c
SRC = src/main.c src/helper.c src/io.c src/md2.c src/md2_impls/md2_common.c src/md2_impls/md2_0.c src/md2_impls/md2_1.c src/md2_impls/md2_2.c src/md2_impls/md2_3.c src/md2_impls/md2_reference/md2_reference.c
OBJ = ${subst src,build,${SRC:.c=.o}}
CC = gcc
CFLAGS = -Ilib -ggdb -std=c11 -g -Wall -Wextra -no-pie -O3
LDFLAGS = -pthread
TESTFILES = t/10000 t/1 t/10 t/100 t/1000 #t/2000 t/5000 t/10000
TESTFILES = t/1 t/2 t/5 t/10 t/20 t/50 t/100 t/1000 t/2000 t/5000 t/10000
TESTFILES_SIZES = ${subst t/,,${TESTFILES}}
all: md2
@ -23,7 +23,7 @@ help:
@echo - benchmarks: run benchmarks (only works on linux!)
build/%.o: src/%.c
@mkdir -p build/md2_impls
@mkdir -p build/md2_impls/md2_reference
${CC} -c ${CFLAGS} -o $@ $<
md2: ${OBJ}
@ -38,21 +38,29 @@ t/%:
benchmarks.csv: md2 ${TESTFILES}
@rm -f $@
@for i in 0 1 2 3; do \
@echo -n "Implementierung" > $@
@for t in $(TESTFILES_SIZES); do \
echo -n ";$$t" >> $@; \
done
@echo "" >> $@
@for i in 0 1 2 3 4; do \
echo ;\
echo "=== Testing implementation $$i ===";\
echo -n "Implementierung-$$i" >> $@; \
for t in $(TESTFILES_SIZES); do \
echo -n "- with $${t}MB ... "; \
if ! rr=$$(./md2 t/$${t} -B1 -V$${i}); then \
echo; \
echo "SKIPPED!"; \
echo "$${i};$${t};0" >> $@; \
echo -n ";0" >> $@; \
else \
r=$$(echo $$rr | xargs | sed -e 's/.*took \(.*\) seconds.*/\1/'); \
echo "$${r}s"; \
echo "$${i};$${t};$${r}" >> $@; \
echo -n ";$${r}" >> $@; \
fi; \
done; \
echo "" >> $@; \
echo "=== done ===";\
echo;\
done

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@ -0,0 +1,6 @@
Implementierung;1;2;5;10;20;50;100
Implementierung-0;0.092604;0.172133;0.422083;0.845732;1.687540;4.232703;8.501036
Implementierung-1;0.084314;0.167799;0.431772;0.843568;1.708024;5.208127;10.147011
Implementierung-2;0.097700;0.203661;0.567091;1.062895;2.141933;5.440520;10.342529
Implementierung-3;0.099547;0.206932;0.546978;1.017148;2.077730;5.067994;9.962873
Implementierung-4;0.117680;0.239349;0.616783;1.200482;2.356915;5.856234;11.647842
1 Implementierung 1 2 5 10 20 50 100
2 Implementierung-0 0.092604 0.172133 0.422083 0.845732 1.687540 4.232703 8.501036
3 Implementierung-1 0.084314 0.167799 0.431772 0.843568 1.708024 5.208127 10.147011
4 Implementierung-2 0.097700 0.203661 0.567091 1.062895 2.141933 5.440520 10.342529
5 Implementierung-3 0.099547 0.206932 0.546978 1.017148 2.077730 5.067994 9.962873
6 Implementierung-4 0.117680 0.239349 0.616783 1.200482 2.356915 5.856234 11.647842

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@ -0,0 +1,63 @@
#ifndef MD2_REF_H
#define MD2_REF_H
/***********************************************************
* WICHTIG:
* Diese Implementierung wurde nicht von uns geschrieben,
* sondern zu vergleichszwechen von der Referenz übernommen.
* Quelle: https://datatracker.ietf.org/doc/html/rfc1319
**********************************************************/
#ifndef PROTOTYPES
#define PROTOTYPES 0
#endif
/* POINTER defines a generic pointer type */
typedef unsigned char *POINTER;
/* UINT2 defines a two byte word */
typedef unsigned short int UINT2;
/* UINT4 defines a four byte word */
typedef unsigned long int UINT4;
/* PROTO_LIST is defined depending on how PROTOTYPES is defined above.
If using PROTOTYPES, then PROTO_LIST returns the list, otherwise it
returns an empty list.
*/
#if PROTOTYPES
#define PROTO_LIST(list) list
#else
#define PROTO_LIST(list) ()
#endif
typedef struct {
unsigned char state[16]; /* state */
unsigned char checksum[16]; /* checksum */
unsigned int count; /* number of bytes, modulo 16 */
unsigned char buffer[16]; /* input buffer */
} MD2_CTX;
void MD2Init PROTO_LIST((MD2_CTX *));
void MD2Update PROTO_LIST((MD2_CTX *, unsigned char *, unsigned int));
void MD2Final PROTO_LIST((unsigned char[16], MD2_CTX *));
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include "../../io.h"
/**
* @brief This implementation is the reference implementation
*
* @param _ unused
* @param filename name of the file to load
* @param out
*/
void md2_hash_ref(size_t len, const uint8_t buf[len], uint8_t out[16]);
#endif // MD2_REF_H

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@ -1,22 +0,0 @@
#ifndef PROTOTYPES
#define PROTOTYPES 0
#endif
/* POINTER defines a generic pointer type */
typedef unsigned char *POINTER;
/* UINT2 defines a two byte word */
typedef unsigned short int UINT2;
/* UINT4 defines a four byte word */
typedef unsigned long int UINT4;
/* PROTO_LIST is defined depending on how PROTOTYPES is defined above.
If using PROTOTYPES, then PROTO_LIST returns the list, otherwise it
returns an empty list.
*/
#if PROTOTYPES
#define PROTO_LIST(list) list
#else
#define PROTO_LIST(list) ()
#endif

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@ -1,36 +0,0 @@
typedef struct {
unsigned char state[16]; /* state */
unsigned char checksum[16]; /* checksum */
unsigned int count; /* number of bytes, modulo 16 */
unsigned char buffer[16]; /* input buffer */
} MD2_CTX;
void MD2Init PROTO_LIST ((MD2_CTX *));
void MD2Update PROTO_LIST
((MD2_CTX *, unsigned char *, unsigned int));
void MD2Final PROTO_LIST ((unsigned char [16], MD2_CTX *));
#ifndef MD2_REF_H
#define MD2_REF_H
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include "../io.h"
/**
* @brief This implementation is the reference implementation
*
* @param _ unused
* @param filename name of the file to load
* @param out
*/
void md2_hash_ref(size_t len, const uint8_t buf[len], uint8_t out[16]);
void md2_checksum_ref(size_t len, uint8_t* buf);
#endif // MD2_REF_H

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@ -5,6 +5,7 @@
#include "../lib/md2_impls/md2_1.h"
#include "../lib/md2_impls/md2_2.h"
#include "../lib/md2_impls/md2_3.h"
#include "../lib/md2_impls/md2_reference/md2_reference.h"
md2_hash_func md2_hash;
md2_checksum_func md2_checksum;
@ -40,6 +41,11 @@ bool md2_choose_implementation(int i) {
md2_checksum = NULL;
return true;
case 4:
md2_hash = md2_hash_ref;
md2_checksum = NULL;
return true;
default:
return false;
}

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@ -1,6 +1,13 @@
/* MD2C.C - RSA Data Security, Inc., MD2 message-digest algorithm
*/
/***********************************************************
* WICHTIG:
* Diese Implementierung wurde nicht von uns geschrieben,
* sondern zu vergleichszwechen von der Referenz übernommen.
* Quelle: https://datatracker.ietf.org/doc/html/rfc1319
**********************************************************/
/* Copyright (C) 1990-2, RSA Data Security, Inc. Created 1990. All
rights reserved.
@ -19,37 +26,35 @@
documentation and/or software.
*/
#include "global.h"
#include "md2_reference.h"
#include "../../../lib/md2_impls/md2_reference/md2_reference.h"
static void MD2Transform PROTO_LIST
((unsigned char [16], unsigned char [16], unsigned char [16]));
static void MD2_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
static void MD2_memset PROTO_LIST ((POINTER, int, unsigned int));
static void MD2Transform PROTO_LIST((unsigned char[16], unsigned char[16],
unsigned char[16]));
static void MD2_memcpy PROTO_LIST((POINTER, POINTER, unsigned int));
static void MD2_memset PROTO_LIST((POINTER, int, unsigned int));
/* 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
};
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 *)"",
@ -65,33 +70,35 @@ static unsigned char *PADDING[] = {
(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"
};
(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"};
void md2_hash_ref(size_t len, const uint8_t buf[len], uint8_t out[16]) {
MD2_CTX context;
MD2Init(&context);
MD2Update(&context, buf, len);
MD2Final(out, &context);
}
/* MD2 initialization. Begins an MD2 operation, writing a new context.
*/
void MD2Init (context)
MD2_CTX *context; /* context */
void MD2Init(context) MD2_CTX *context; /* context */
{
context->count = 0;
MD2_memset ((POINTER)context->state, 0, sizeof (context->state));
MD2_memset
((POINTER)context->checksum, 0, sizeof (context->checksum));
MD2_memset((POINTER)context->state, 0, sizeof(context->state));
MD2_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 */
void MD2Update(context, input, inputLen) MD2_CTX *context; /* context */
unsigned char *input; /* input block */
unsigned int inputLen; /* length of input block */
{
@ -106,30 +113,27 @@ unsigned int inputLen; /* length of input block */
/* Transform as many times as possible.
*/
if (inputLen >= partLen) {
MD2_memcpy
((POINTER)&context->buffer[index], (POINTER)input, partLen);
MD2Transform (context->state, context->checksum, context->buffer);
MD2_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]);
MD2Transform(context->state, context->checksum, &input[i]);
index = 0;
}
else
} else
i = 0;
/* Buffer remaining input */
MD2_memcpy
((POINTER)&context->buffer[index], (POINTER)&input[i],
inputLen-i);
MD2_memcpy((POINTER)&context->buffer[index], (POINTER)&input[i],
inputLen - i);
}
/* MD2 finalization. Ends an MD2 message-digest operation, writing the
message digest and zeroizing the context.
*/
void MD2Final (digest, context)
void MD2Final(digest, context)
unsigned char digest[16]; /* message digest */
unsigned char digest[16]; /* message digest */
MD2_CTX *context; /* context */
{
unsigned int index, padLen;
@ -138,24 +142,23 @@ MD2_CTX *context; /* context */
*/
index = context->count;
padLen = 16 - index;
MD2Update (context, PADDING[padLen], padLen);
MD2Update(context, PADDING[padLen], padLen);
/* Extend with checksum */
MD2Update (context, context->checksum, 16);
MD2Update(context, context->checksum, 16);
/* Store state in digest */
MD2_memcpy ((POINTER)digest, (POINTER)context->state, 16);
MD2_memcpy((POINTER)digest, (POINTER)context->state, 16);
/* Zeroize sensitive information.
*/
MD2_memset ((POINTER)context, 0, sizeof (*context));
MD2_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];
static void MD2Transform(state, checksum, block) unsigned char state[16];
unsigned char checksum[16];
unsigned char block[16];
{
@ -164,57 +167,49 @@ unsigned char block[16];
/* Form encryption block from state, block, state ^ block.
*/
MD2_memcpy ((POINTER)x, (POINTER)state, 16);
MD2_memcpy ((POINTER)x+16, (POINTER)block, 16);
for (i = 0; i < 16; i++)
x[i+32] = state[i] ^ block[i];
MD2_memcpy((POINTER)x, (POINTER)state, 16);
MD2_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];
for (j = 0; j < 48; j++) t = x[j] ^= PI_SUBST[t];
t = (t + i) & 0xff;
}
/* Save new state */
MD2_memcpy ((POINTER)state, (POINTER)x, 16);
/* Save new state */
MD2_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];
for (i = 0; i < 16; i++) t = checksum[i] ^= PI_SUBST[block[i] ^ t];
/* Zeroize sensitive information.
*/
MD2_memset ((POINTER)x, 0, sizeof (x));
MD2_memset((POINTER)x, 0, sizeof(x));
}
/* Note: Replace "for loop" with standard memcpy if possible.
*/
static void MD2_memcpy (output, input, len)
POINTER output;
static void MD2_memcpy(output, input, len) POINTER output;
POINTER input;
unsigned int len;
{
unsigned int i;
for (i = 0; i < len; i++)
output[i] = input[i];
for (i = 0; i < len; i++) output[i] = input[i];
}
/* Note: Replace "for loop" with standard memset if possible.
*/
static void MD2_memset (output, value, len)
POINTER output;
static void MD2_memset(output, value, len) POINTER output;
int value;
unsigned int len;
{
unsigned int i;
for (i = 0; i < len; i++)
((char *)output)[i] = (char)value;
for (i = 0; i < len; i++) ((char *)output)[i] = (char)value;
}

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@ -1,209 +0,0 @@
/* MDDRIVER.C - test driver for MD2, MD4 and MD5
*/
/* Copyright (C) 1990-2, RSA Data Security, Inc. Created 1990. All
rights reserved.
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.
*/
/* The following makes MD default to MD5 if it has not already been
defined with C compiler flags.
*/
#ifndef MD
#define MD MD5
#endif
#include <stdio.h>
#include <time.h>
#include <string.h>
#include "global.h"
#if MD == 2
#include "md2_reference.h"
#endif
/* Length of test block, number of test blocks.
*/
#define TEST_BLOCK_LEN 1000
#define TEST_BLOCK_COUNT 1000
static void MDString PROTO_LIST ((char *));
static void MDTimeTrial PROTO_LIST ((void));
static void MDTestSuite PROTO_LIST ((void));
static void MDFile PROTO_LIST ((char *));
static void MDFilter PROTO_LIST ((void));
static void MDPrint PROTO_LIST ((unsigned char [16]));
#if MD == 2
#define MD_CTX MD2_CTX
#define MDInit MD2Init
#define MDUpdate MD2Update
#define MDFinal MD2Final
#endif
/* Main driver.
Arguments (may be any combination):
-sstring - digests string
-t - runs time trial
-x - runs test script
filename - digests file
(none) - digests standard input
*/
int main (argc, argv)
int argc;
char *argv[];
{
int i;
if (argc > 1)
for (i = 1; i < argc; i++)
if (argv[i][0] == '-' && argv[i][1] == 's')
MDString (argv[i] + 2);
else if (strcmp (argv[i], "-t") == 0)
MDTimeTrial ();
else if (strcmp (argv[i], "-x") == 0)
MDTestSuite ();
else
MDFile (argv[i]);
else
MDFilter ();
return (0);
}
/* Digests a string and prints the result.
*/
static void MDString (string)
char *string;
{
MD_CTX context;
unsigned char digest[16];
unsigned int len = strlen (string);
MDInit (&context);
MDUpdate (&context, string, len);
MDFinal (digest, &context);
printf ("MD%d (\"%s\") = ", MD, string);
MDPrint (digest);
printf ("\n");
}
/* Measures the time to digest TEST_BLOCK_COUNT TEST_BLOCK_LEN-byte
blocks.
*/
static void MDTimeTrial ()
{
MD_CTX context;
time_t endTime, startTime;
unsigned char block[TEST_BLOCK_LEN], digest[16];
unsigned int i;
printf
("MD%d time trial. Digesting %d %d-byte blocks ...", MD,
TEST_BLOCK_LEN, TEST_BLOCK_COUNT);
/* Initialize block */
for (i = 0; i < TEST_BLOCK_LEN; i++)
block[i] = (unsigned char)(i & 0xff);
/* Start timer */
time (&startTime);
/* Digest blocks */
MDInit (&context);
for (i = 0; i < TEST_BLOCK_COUNT; i++)
MDUpdate (&context, block, TEST_BLOCK_LEN);
MDFinal (digest, &context);
/* Stop timer */
time (&endTime);
printf (" done\n");
printf ("Digest = ");
MDPrint (digest);
printf ("\nTime = %ld seconds\n", (long)(endTime-startTime));
printf
("Speed = %ld bytes/second\n",
(long)TEST_BLOCK_LEN * (long)TEST_BLOCK_COUNT/(endTime-startTime));
}
/* Digests a reference suite of strings and prints the results.
*/
static void MDTestSuite ()
{
printf ("MD%d test suite:\n", MD);
MDString ("");
MDString ("a");
MDString ("abc");
MDString ("message digest");
MDString ("abcdefghijklmnopqrstuvwxyz");
MDString
("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789");
MDString
("1234567890123456789012345678901234567890\
1234567890123456789012345678901234567890");
}
/* Digests a file and prints the result.
*/
static void MDFile (filename)
char *filename;
{
FILE *file;
MD_CTX context;
int len;
unsigned char buffer[1024], digest[16];
if ((file = fopen (filename, "rb")) == NULL)
printf ("%s can't be opened\n", filename);
else {
MDInit (&context);
while (len = fread (buffer, 1, 1024, file))
MDUpdate (&context, buffer, len);
MDFinal (digest, &context);
fclose (file);
printf ("MD%d (%s) = ", MD, filename);
MDPrint (digest);
printf ("\n");
}
}
/* Digests the standard input and prints the result.
*/
static void MDFilter ()
{
MD_CTX context;
int len;
unsigned char buffer[16], digest[16];
MDInit (&context);
while (len = fread (buffer, 1, 16, stdin))
MDUpdate (&context, buffer, len);
MDFinal (digest, &context);
MDPrint (digest);
printf ("\n");
}
/* Prints a message digest in hexadecimal.
*/
static void MDPrint (digest)
unsigned char digest[16];
{
unsigned int i;
for (i = 0; i < 16; i++)
printf ("%02x", digest[i]);
}