Implementierung/Makefile

@@ -4,7 +4,7 @@ SRC = src/main.c src/helper.c src/io.c src/md2.c src/md2_impls/md2_common.c src/
 OBJ = ${subst src,build,${SRC:.c=.o}}
 CC = gcc
 CFLAGS = -Ilib -ggdb -std=c11 -g -Wall -Wextra -no-pie -O3
-LDFLAGS = -pthread
+LDFLAGS = 
 
 all: md2
 

Implementierung/lib/md2_impls/md2_3.h

@@ -1,7 +1,6 @@
 #ifndef MD2_3_H
 #define MD2_3_H
 
-#include <pthread.h>
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -12,10 +11,10 @@
 #include <unistd.h>
 
 /**
- * @brief Diese Implementierung benutzt Threads zum Berechnen des Hashs
+ * @brief This implementation loads the file in bits and not at once
  *
- * @param len
- * @param buf
+ * @param _ unused
+ * @param filename name of the file to load
  * @param out
  */
 void md2_hash_3(size_t len, const uint8_t buf[len], uint8_t out[16]);

Implementierung/src/md2_impls/md2_3.c

@@ -2,13 +2,7 @@
 
 #include "../../lib/md2_impls/md2_common.h"
 
-struct thread_args {
-  size_t len;
-  const uint8_t* buf;
-};
-
-void process_nothread_hash(size_t len, uint8_t buf[len],
-                           uint8_t messageDigestBuf[48]) {
+void process_hash(size_t len, uint8_t buf[len], uint8_t messageDigestBuf[48]) {
   for (size_t i = 0; i < (len + 16) / 16 - 1; i++) {
     for (int j = 0; j < 16; j++) {
       messageDigestBuf[16 + j] = buf[i * 16 + j];
@@ -27,57 +21,36 @@ void process_nothread_hash(size_t len, uint8_t buf[len],
   }
 }
 
-void* process_hash(void* threadArgs) {
-  struct thread_args* args = (struct thread_args*)threadArgs;
-
-  uint8_t* messageDigestBuf = calloc(48, sizeof(uint8_t));
-  if (messageDigestBuf == NULL) {
-    return;
-  }
-
-  for (size_t i = 0; i < (args->len + 16) / 16 - 1; i++) {
-    for (int j = 0; j < 16; j++) {
-      messageDigestBuf[16 + j] = args->buf[i * 16 + j];
-      messageDigestBuf[32 + j] =
-          (messageDigestBuf[16 + j] ^ messageDigestBuf[j]);
-    }
-
-    u_int8_t t = 0;
-
-    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;
-    }
-  }
-  pthread_exit(messageDigestBuf);
-}
-
-void* process_checksum(void* threasdArgs) {
-  struct thread_args* args = (struct thread_args*)threasdArgs;
-
-  uint8_t* checksum = calloc(16, sizeof(uint8_t));
-  if (checksum == NULL) {
-    return;
-  }
-
+void process_checksum(size_t len, uint8_t buf[len], uint8_t checksum[16]) {
   uint8_t l = 0;
 
-  for (size_t i = 0; i < args->len / 16; i++) {
+  for (size_t i = 0; i < len / 16; i++) {
     for (int j = 0; j < 16; j++) {
-      u_int8_t c = args->buf[i * 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:
       l = checksum[j] ^= MD2_PI_SUBST[c ^ l];
     }
   }
-  pthread_exit(checksum);
 }
 
+// DUPLICATE CODE FROM md2_2.c
+// int apply_padding(size_t len, uint8_t buf[len]) {
+//   int paddingNeeded = 16 - (len % 16);
+//   uint8_t originalPadding = paddingNeeded;
+//   len += paddingNeeded;
+
+//   while (paddingNeeded > 0) {
+//     buf[len - paddingNeeded] = originalPadding;
+//     paddingNeeded--;
+//   }
+//   return len;
+// }
+
 // unused!
 void md2_checksum_3(size_t _, uint8_t* __) {}
 
 void md2_hash_3(size_t len, const uint8_t buf[len], uint8_t out[16]) {
+  // === step 1 ===
   int paddingNeeded = 16 - (len % 16);
   uint8_t originalPadding = paddingNeeded;
   len += paddingNeeded;
@@ -94,35 +67,64 @@ void md2_hash_3(size_t len, const uint8_t buf[len], uint8_t out[16]) {
     paddingNeeded--;
   }
 
-  pthread_t thread_1, thread_2;
-
-  struct thread_args thread_args = {len, newBuf};
-
-  if (pthread_create(&thread_1, NULL, process_hash, (void*)&thread_args) != 0) {
-    printf("Error creating thread 1\n");
-    exit(EXIT_FAILURE);
-  }
-  if (pthread_create(&thread_2, NULL, process_checksum, (void*)&thread_args) !=
-      0) {
-    printf("Error creating thread 2\n");
-    exit(EXIT_FAILURE);
+  // === step 3 ===
+  uint8_t* messageDigestBuf = calloc(48, sizeof(uint8_t));
+  if (messageDigestBuf == NULL) {
+    return;
   }
 
-  u_int8_t* messageDigestBuf;
-  u_int8_t* checksum;
-
-  if (pthread_join(thread_1, (void**)&messageDigestBuf) != 0) {
-    printf("Error joining thread 1\n");
-    exit(EXIT_FAILURE);
-  }
-  if (pthread_join(thread_2, (void**)&checksum) != 0) {
-    printf("Error joining thread 2\n");
-    exit(EXIT_FAILURE);
+  // === step 4 ===
+  uint8_t* checksum = calloc(16, sizeof(uint8_t));
+  if (checksum == NULL) {
+    return;
   }
 
-  process_nothread_hash(16, checksum, messageDigestBuf);
+  int hashPipe[2];
+  int checksumPipe[2];
+
+  if (pipe(hashPipe) == -1 || pipe(checksumPipe) == -1) {
+    return;
+  }
+
+  pid_t pid_1, pid_2;
+  (pid_1 = fork()) && (pid_2 = fork());
+
+  if (pid_1 == 0) {
+    // Child 1 process
+    close(hashPipe[0]);
+    process_hash(len, newBuf, messageDigestBuf);
+    write(hashPipe[1], messageDigestBuf, 48);
+    exit(0);
+
+  } else if (pid_2 == 0) {
+    // Child 2 process
+    close(checksumPipe[0]);
+    process_checksum(len, newBuf, checksum);
+    write(checksumPipe[1], checksum, 16);
+    exit(0);
+  } else {
+    // int status;
+    // Parent process
+    close(hashPipe[1]);
+    close(checksumPipe[1]);
+
+    waitpid(pid_1, NULL, 0);
+    waitpid(pid_2, NULL, 0);
+
+    read(hashPipe[0], messageDigestBuf, 48);
+    read(checksumPipe[0], checksum, 16);
+
+    process_hash(16, checksum, messageDigestBuf);
     memcpy(out, messageDigestBuf, 16);
 
+    // free(data);
     free(messageDigestBuf);
     free(checksum);
   }
+
+  // process_block_checksum(data, checksum, &l);
+  // process_block_hash(data, messageDigestBuf);
+
+  // process_block_checksum(data, checksum, &l);
+  // process_block_hash(data, messageDigestBuf);
+}