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14 changed files with 224 additions and 188 deletions

View file

@ -9,7 +9,7 @@ ifeq ($(DETAILED_BENCHMARK), true)
CFLAGS += -DMD2_DETAILED_BENCHMARK
endif
LDFLAGS = -pthread
TESTFILES = t/1 t/2 t/5 t/7 t/10 t/25 t/50 t/75 t/100 t/250 t/500 t/750 t/1000 t/1500 t/2000 t/2500 t/3000 t/3500 t/4000 t/4500 t/5000 t/5500 t/6000 t/6500 t/7000 t/7500 t/8000 t/8500 t/9000 t/9500 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}}
BLUE=\033[1;36m
RED=\033[1;31m
@ -44,7 +44,7 @@ t/%:
@mkdir -p t
@echo
@echo -e "${BLUE}=== Generating ${subst t/,,$@}MB of random data... ===${NC}"
dd if=/dev/urandom of=$@ bs=1M count=${subst t/,,$@} status=progress
dd if=/dev/random of=$@ bs=1M count=${subst t/,,$@} status=progress
@echo -e "${BLUE}=== done ===${NC}"
@echo
@ -56,7 +56,7 @@ benchmarks.csv: md2 ${TESTFILES}
done
@echo "" >> $@
@for i in 4; do \
@for i in 0 1 2 3 4; do \
echo ;\
echo -e "${BLUE}=== Testing implementation $$i ===${NC}";\
echo -n "Implementierung-$$i" >> $@; \

View file

@ -1,2 +1,6 @@
Implementierung;1;2;5;7;10;25;50;75;100;250;500;750;1000;1500;2000;2500;3000;3500;4000;4500;5000;5500
Implementierung-4;0.179950;0.308132;0.768091;1.077839;1.793499;3.786488;7.788925;11.049307;15.051300;37.564573;74.324851;112.160912;150.740498;225.111342;305.938520;381.063308;463.611798;533.670234;614.535749;63.418839;137.076754;292.555679
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 7 10 20 25 50 100 75 250 500 750 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
2 Implementierung-4 Implementierung-0 0.179950 0.092604 0.308132 0.172133 0.768091 0.422083 1.077839 1.793499 0.845732 1.687540 3.786488 7.788925 4.232703 15.051300 8.501036 11.049307 37.564573 74.324851 112.160912 150.740498 225.111342 305.938520 381.063308 463.611798 533.670234 614.535749 63.418839 137.076754 292.555679
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

View file

@ -10,6 +10,7 @@
typedef void (*md2_hash_func)(size_t len, const uint8_t buf[len],
uint8_t out[16]);
typedef void (*md2_checksum_func)(size_t len, uint8_t* buf);
/**
* @brief Calculates checksum of buf and stores it in out
@ -20,6 +21,15 @@ typedef void (*md2_hash_func)(size_t len, const uint8_t buf[len],
*/
extern md2_hash_func md2_hash;
/**
* @brief Calculates checksum of buf and appends it to buf
*
* @param len Length of data which the checksum should be calculated of
* @param buf Location of the data. Make sure to reserve 16 bytes more so the
* chechsum fits!
*/
extern md2_checksum_func md2_checksum;
/**
* @brief Choose the implementation to use
*

View file

@ -9,5 +9,6 @@
#include <sys/types.h>
void md2_hash_0(size_t len, const uint8_t buf[len], uint8_t out[16]);
void md2_checksum_0(size_t len, uint8_t* buf);
#endif // MD2_0_H

View file

@ -9,5 +9,6 @@
#include <sys/types.h>
void md2_hash_1(size_t len, const uint8_t buf[len], uint8_t out[16]);
void md2_checksum_1(size_t len, uint8_t* buf);
#endif // MD2_1_H

View file

@ -59,73 +59,8 @@ extern unsigned char MD2_PI_SUBST[256];
*/
void md2_print_buf(size_t len, uint8_t buf[len]);
/**
* @brief Calculates checksum of buf and appends it to buf
*
* @param len Length of data which the checksum should be calculated of
* @param buf Location of the data. Make sure to reserve 16 bytes more so the
* chechsum fits!
*/
void md2_checksum(size_t len, uint8_t* buf);
/**
* @brief Calculates checksum of buf and writes it into a target
*
* @param len Length of data which the checksum should be calculated of
* @param buf Location of the data. Make sure to reserve 16 bytes more so the
* chechsum fits!
* @param checksum the output checksum
*/
void md2_checksum_with_target(size_t len, const uint8_t* buf,
uint8_t checksum[16]);
/**
* @brief Process one block of the checksum
*
* @param block the block to process
* @param checksum the output checksum
* @param l the current l
*/
void md2_process_block_checksum(uint8_t const block[16], uint8_t checksum[16],
uint8_t* l);
/**
* @brief Stores the time if start of a step, calculates the duration if end
*
* @param step the step to process
*/
void md2_process_detailed_benchmark_step(enum md2_detailed_benchmark_step step);
/**
* @brief Print the detailed benchmark result
*
*/
void md2_print_detailed_benchmark_result();
/**
* @brief Add padding and allocate extra space for the checksum
*
* @param buf buffer of the whole message
* @param len length of buf
* @return uint8_t* pointer to the new buffer
*/
uint8_t* md2_add_padding_and_space_for_checksum(const uint8_t* buf,
size_t* len);
/**
* @brief The second loop of the md2 algorithm
*
* @param messageDigestBuf the message digest buffer
*/
void md2_second_loop(uint8_t* messageDigestBuf);
/**
* @brief The first loop of the md2 algorithm
*
* @param buf buffer of the whole message
* @param messageDigestBuf the message digest buffer
* @param i the index of the 16-byte message block
*/
void md2_first_loop(const uint8_t* buf, uint8_t* messageDigestBuf, int i);
#endif // MD2_COMMON_H

View file

@ -8,15 +8,6 @@
* Quelle: https://datatracker.ietf.org/doc/html/rfc1319
**********************************************************/
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include "../md2_common.h"
#ifndef PROTOTYPES
#define PROTOTYPES 0
#endif
@ -43,14 +34,21 @@ typedef unsigned long int UINT4;
typedef struct {
unsigned char state[16]; /* state */
unsigned char checksum[16]; /* checksum */
size_t count; /* number of bytes, modulo 16 */
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 *, size_t));
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>
void md2_hash_ref(size_t len, const uint8_t buf[len], uint8_t out[16]);
#endif // MD2_REF_H
#endif // MD2_REF_H

View file

@ -8,13 +8,11 @@
#include "../lib/md2_impls/md2_reference/md2_reference.h"
md2_hash_func md2_hash;
md2_checksum_func md2_checksum;
// The file "testfile" should lead to this hash:
// fc982e558db259f298b43cd4c1241c66
static md2_hash_func md2_implementations[] = {
md2_hash_0, md2_hash_1, md2_hash_2, md2_hash_3, md2_hash_ref};
void md2_encode_hash(uint8_t hash[16], char* string_hash) {
for (int i = 0; i < 16; i++) {
sprintf(string_hash + (2 * i), "%02x", hash[i]);
@ -22,7 +20,33 @@ void md2_encode_hash(uint8_t hash[16], char* string_hash) {
}
bool md2_choose_implementation(int i) {
if (i < 0 || i > 4) return false;
md2_hash = md2_implementations[i];
return true;
switch (i) {
case 0:
md2_hash = md2_hash_0;
md2_checksum = md2_checksum_0;
return true;
case 1:
md2_hash = md2_hash_1;
md2_checksum = md2_checksum_1;
return true;
case 2:
md2_hash = md2_hash_2;
md2_checksum = NULL;
return true;
case 3:
md2_hash = md2_hash_3;
md2_checksum = NULL;
return true;
case 4:
md2_hash = md2_hash_ref;
md2_checksum = NULL;
return true;
default:
return false;
}
}

View file

@ -2,15 +2,50 @@
#include "../../lib/md2_impls/md2_common.h"
void md2_checksum_0(size_t len, uint8_t* buf) {
uint8_t l = 0;
for (size_t i = 0; i < len / 16; i++) {
for (int j = 0; j < 16; j++) {
u_int8_t c = buf[i * 16 + j];
// reference is wrong. It says: Set C[j] to S[c xor L]. But it should be:
buf[len + j] ^= MD2_PI_SUBST[c ^ l];
l = buf[len + j];
}
}
}
void md2_hash_0(size_t len, const uint8_t buf[len], uint8_t out[16]) {
// === step 1 ===
uint8_t* newBuf = md2_add_padding_and_space_for_checksum(buf, &len);
int paddingNeeded = 16 - (len % 16);
uint8_t originalPadding = paddingNeeded;
len += paddingNeeded;
// printf("len: %d\n", len);
// +16 for the checksum
uint8_t* newBuf = calloc(len + 16, sizeof(uint8_t));
if (newBuf == NULL) {
return;
}
memcpy(newBuf, buf, len - paddingNeeded);
// printBuf(len + 16, newBuf);
while (paddingNeeded > 0) {
newBuf[len - paddingNeeded] = originalPadding;
paddingNeeded--;
}
// printf("buf with padding: ");
// printBuf(len + 16, newBuf);
// === step 2 ===
md2_checksum(len, newBuf);
CHECKSUM_START_MARK
md2_checksum_0(len, newBuf);
CHECKSUM_END_MARK
// printf("buf with cecksum: ");
// printBuf(len + 16, newBuf);
// === step 3 ===
uint8_t* messageDigestBuf = calloc(48, sizeof(uint8_t));
@ -19,11 +54,29 @@ void md2_hash_0(size_t len, const uint8_t buf[len], uint8_t out[16]) {
}
// === step 4 ===
// <= because we need to hash the last block (the checksum) too
for (size_t i = 0; i <= (len) / 16; i++) {
md2_first_loop(newBuf, messageDigestBuf, i);
md2_second_loop(messageDigestBuf);
// <= because we need to hash the last block too
for (size_t i = 0; i <= (len + 16) / 16 - 1; i++) {
FIRST_LOOP_START_MARK
for (int j = 0; j < 16; j++) {
messageDigestBuf[16 + j] = newBuf[i * 16 + j];
messageDigestBuf[32 + j] =
(messageDigestBuf[16 + j] ^ messageDigestBuf[j]);
}
FIRST_LOOP_END_MARK
u_int8_t t = 0;
SECOND_LOOP_START_MARK
for (int j = 0; j < 18; j++) {
for (int k = 0; k < 48; k++) {
t = messageDigestBuf[k] = messageDigestBuf[k] ^ MD2_PI_SUBST[t];
}
t = (t + j) % 256;
}
SECOND_LOOP_END_MARK
}
// printf("messageDigestBuf: \n");
// printBuf(16, messageDigestBuf);
END_MARK
memcpy(out, messageDigestBuf, 16);

View file

@ -4,6 +4,19 @@
#include "../../lib/md2_impls/md2_common.h"
void md2_checksum_1(size_t len, uint8_t *buf) {
uint8_t l = 0;
for (size_t i = 0; i < len / 16; i++) {
for (int j = 0; j < 16; j++) {
u_int8_t c = buf[i * 16 + j];
// reference is wrong. It says: Set C[j] to S[c xor L]. But it should be:
buf[len + j] ^= MD2_PI_SUBST[c ^ l];
l = buf[len + j];
}
}
}
static uint8_t PADDING[17][16] = {
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
@ -42,7 +55,9 @@ void md2_hash_1(size_t len, const uint8_t buf[len], uint8_t out[16]) {
memcpy(newBuf + len - paddingNeeded, PADDING + paddingNeeded, paddingNeeded);
// === step 2 ===
md2_checksum(len, newBuf);
CHECKSUM_START_MARK
md2_checksum_1(len, newBuf);
CHECKSUM_END_MARK
// === step 3 ===
uint8_t *messageDigestBuf = aligned_alloc(16, sizeof(uint8_t) * 48);
@ -66,7 +81,16 @@ void md2_hash_1(size_t len, const uint8_t buf[len], uint8_t out[16]) {
_mm_store_si128((__m128i *)(messageDigestBuf + 32), vy);
FIRST_LOOP_END_MARK
md2_second_loop(messageDigestBuf);
u_int8_t t = 0;
SECOND_LOOP_START_MARK
for (int j = 0; j < 18; j++) {
for (int k = 0; k < 48; k++) {
t = messageDigestBuf[k] = messageDigestBuf[k] ^ MD2_PI_SUBST[t];
}
t = (t + j) & 255;
}
SECOND_LOOP_END_MARK
}
END_MARK

View file

@ -3,8 +3,32 @@
#include "../../lib/md2_impls/md2_common.h"
void process_block_hash(uint8_t block[16], uint8_t messageDigestBuf[48]) {
md2_first_loop(block, messageDigestBuf, 0);
md2_second_loop(messageDigestBuf);
FIRST_LOOP_START_MARK
for (int j = 0; j < 16; j++) {
messageDigestBuf[16 + j] = block[j];
messageDigestBuf[32 + j] = (messageDigestBuf[16 + j] ^ messageDigestBuf[j]);
}
FIRST_LOOP_END_MARK
u_int8_t t = 0;
SECOND_LOOP_START_MARK
for (int j = 0; j < 18; j++) {
for (int k = 0; k < 48; k++) {
t = messageDigestBuf[k] = messageDigestBuf[k] ^ MD2_PI_SUBST[t];
}
t = (t + j) % 256;
}
SECOND_LOOP_END_MARK
}
void process_block_checksum(uint8_t block[16], uint8_t checksum[16],
uint8_t* l) {
for (int j = 0; j < 16; j++) {
u_int8_t c = block[j];
// reference is wrong. It says: Set C[j] to S[c xor L]. But it should be:
(*l) = checksum[j] ^= MD2_PI_SUBST[c ^ (*l)];
}
}
void apply_padding(size_t len, uint8_t buf[16]) {
@ -55,7 +79,7 @@ void md2_hash_2(size_t len, const uint8_t buf[len], uint8_t out[16]) {
}
CHECKSUM_START_MARK
md2_process_block_checksum(data, checksum, &l);
process_block_checksum(data, checksum, &l);
CHECKSUM_END_MARK
process_block_hash(data, messageDigestBuf);
@ -63,7 +87,7 @@ void md2_hash_2(size_t len, const uint8_t buf[len], uint8_t out[16]) {
};
apply_padding(bytes_left_to_process % 16, data);
md2_process_block_checksum(data, checksum, &l);
process_block_checksum(data, checksum, &l);
process_block_hash(data, messageDigestBuf);
process_block_hash(checksum, messageDigestBuf);

View file

@ -10,8 +10,24 @@ struct thread_args {
void process_nothread_hash(size_t len, const uint8_t buf[len],
uint8_t messageDigestBuf[48]) {
for (size_t i = 0; i < (len + 16) / 16 - 1; i++) {
md2_first_loop(buf, messageDigestBuf, i);
md2_second_loop(messageDigestBuf);
FIRST_LOOP_START_MARK
for (int j = 0; j < 16; j++) {
messageDigestBuf[16 + j] = buf[i * 16 + j];
messageDigestBuf[32 + j] =
(messageDigestBuf[16 + j] ^ messageDigestBuf[j]);
}
FIRST_LOOP_END_MARK
u_int8_t t = 0;
SECOND_LOOP_START_MARK
for (int j = 0; j < 18; j++) {
for (int k = 0; k < 48; k++) {
t = messageDigestBuf[k] = messageDigestBuf[k] ^ MD2_PI_SUBST[t];
}
t = (t + j) % 256;
}
SECOND_LOOP_END_MARK
}
}
@ -35,16 +51,36 @@ void* process_checksum(void* threasdArgs) {
return NULL;
}
md2_checksum_with_target(args->len, args->buf, checksum);
uint8_t l = 0;
CHECKSUM_START_MARK
for (size_t i = 0; i < args->len / 16; i++) {
for (int j = 0; j < 16; j++) {
u_int8_t c = args->buf[i * 16 + j];
// reference is wrong. It says: Set C[j] to S[c xor L]. But it should be:
l = checksum[j] ^= MD2_PI_SUBST[c ^ l];
}
}
CHECKSUM_END_MARK
pthread_exit(checksum);
}
void md2_hash_3(size_t len, const uint8_t buf[len], uint8_t out[16]) {
uint8_t* newBuf = md2_add_padding_and_space_for_checksum(buf, &len);
int paddingNeeded = 16 - (len % 16);
uint8_t originalPadding = paddingNeeded;
len += paddingNeeded;
uint8_t* newBuf = calloc(len + 16, sizeof(uint8_t));
if (newBuf == NULL) {
return;
}
memcpy(newBuf, buf, len - paddingNeeded);
while (paddingNeeded > 0) {
newBuf[len - paddingNeeded] = originalPadding;
paddingNeeded--;
}
pthread_t thread_1, thread_2;
struct thread_args thread_args = {len, newBuf};

View file

@ -57,71 +57,4 @@ void md2_print_detailed_benchmark_result() {
printf(" First loop: %f\n", detailed_benchmark_times[1]);
printf(" Second loop: %f\n", detailed_benchmark_times[2]);
printf("\n");
}
uint8_t* md2_add_padding_and_space_for_checksum(const uint8_t* buf,
size_t* len) {
int paddingNeeded = 16 - ((*len) % 16);
uint8_t originalPadding = paddingNeeded;
(*len) += paddingNeeded;
// +16 for the checksum
uint8_t* newBuf = calloc((*len) + 16, sizeof(uint8_t));
if (newBuf == NULL) {
return NULL;
}
memcpy(newBuf, buf, (*len) - paddingNeeded);
while (paddingNeeded > 0) {
newBuf[(*len) - paddingNeeded] = originalPadding;
paddingNeeded--;
}
return newBuf;
}
void md2_process_block_checksum(uint8_t const block[16], uint8_t checksum[16],
uint8_t* l) {
for (int j = 0; j < 16; j++) {
u_int8_t c = block[j];
// reference is wrong. It says: Set C[j] to S[c xor L]. But it should be:
(*l) = checksum[j] ^= MD2_PI_SUBST[c ^ (*l)];
}
}
void md2_checksum(size_t len, uint8_t* buf) {
md2_checksum_with_target(len, buf, buf + len);
}
void md2_checksum_with_target(size_t len, const uint8_t* buf,
uint8_t checksum[16]) {
CHECKSUM_START_MARK
uint8_t l = 0;
for (size_t i = 0; i < len / 16; i++) {
md2_process_block_checksum(buf + i * 16, checksum, &l);
}
CHECKSUM_END_MARK
}
void md2_second_loop(uint8_t* messageDigestBuf) {
u_int8_t t = 0;
SECOND_LOOP_START_MARK
for (int j = 0; j < 18; j++) {
for (int k = 0; k < 48; k++) {
t = messageDigestBuf[k] = messageDigestBuf[k] ^ MD2_PI_SUBST[t];
}
t = (t + j) & 255;
}
SECOND_LOOP_END_MARK
}
void md2_first_loop(const uint8_t* buf, uint8_t* messageDigestBuf, int i) {
FIRST_LOOP_START_MARK
for (int j = 0; j < 16; j++) {
messageDigestBuf[16 + j] = buf[i * 16 + j];
messageDigestBuf[32 + j] = (messageDigestBuf[16 + j] ^ messageDigestBuf[j]);
}
FIRST_LOOP_END_MARK
}

View file

@ -30,8 +30,8 @@
static void MD2Transform PROTO_LIST((unsigned char[16], unsigned char[16],
unsigned char[16]));
static void MD2_memcpy PROTO_LIST((POINTER, POINTER, size_t));
static void MD2_memset PROTO_LIST((POINTER, int, size_t));
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.
@ -83,7 +83,6 @@ void md2_hash_ref(size_t len, const uint8_t buf[len], uint8_t out[16]) {
MD2Init(&context);
MD2Update(&context, buf, len);
MD2Final(out, &context);
END_MARK
}
/* MD2 initialization. Begins an MD2 operation, writing a new context.
@ -101,9 +100,9 @@ void MD2Init(context) MD2_CTX *context; /* context */
*/
void MD2Update(context, input, inputLen) MD2_CTX *context; /* context */
unsigned char *input; /* input block */
size_t inputLen; /* length of input block */
unsigned int inputLen; /* length of input block */
{
size_t i, index, partLen;
unsigned int i, index, partLen;
/* Update number of bytes mod 16 */
index = context->count;
@ -137,7 +136,7 @@ void MD2Final(digest, context)
unsigned char digest[16]; /* message digest */
MD2_CTX *context; /* context */
{
size_t index, padLen;
unsigned int index, padLen;
/* Pad out to multiple of 16.
*/
@ -163,36 +162,30 @@ static void MD2Transform(state, checksum, block) unsigned char state[16];
unsigned char checksum[16];
unsigned char block[16];
{
size_t i, j, t;
unsigned int i, j, t;
unsigned char x[48];
/* Form encryption block from state, block, state ^ block.
*/
MD2_memcpy((POINTER)x, (POINTER)state, 16);
MD2_memcpy((POINTER)x + 16, (POINTER)block, 16);
FIRST_LOOP_START_MARK
for (i = 0; i < 16; i++) x[i + 32] = state[i] ^ block[i];
FIRST_LOOP_END_MARK
/* Encrypt block (18 rounds).
*/
t = 0;
SECOND_LOOP_START_MARK
for (i = 0; i < 18; i++) {
for (j = 0; j < 48; j++) t = x[j] ^= PI_SUBST[t];
t = (t + i) & 0xff;
}
SECOND_LOOP_END_MARK
/* Save new state */
MD2_memcpy((POINTER)state, (POINTER)x, 16);
/* Update checksum.
*/
CHECKSUM_START_MARK
t = checksum[15];
for (i = 0; i < 16; i++) t = checksum[i] ^= PI_SUBST[block[i] ^ t];
CHECKSUM_END_MARK
/* Zeroize sensitive information.
*/
@ -203,9 +196,9 @@ unsigned char block[16];
*/
static void MD2_memcpy(output, input, len) POINTER output;
POINTER input;
size_t len;
unsigned int len;
{
size_t i;
unsigned int i;
for (i = 0; i < len; i++) output[i] = input[i];
}
@ -214,9 +207,9 @@ size_t len;
*/
static void MD2_memset(output, value, len) POINTER output;
int value;
size_t len;
unsigned int len;
{
size_t i;
unsigned int i;
for (i = 0; i < len; i++) ((char *)output)[i] = (char)value;
}