q9

question8/check_pass.c

@@ -9,7 +9,6 @@ int check_pass(char *filename, uid_t user_id, char *password)
 {
     FILE *f;
     char *line = NULL;
-    char delim[] = ":"; 
     char *pwd;
     char *uid;
     size_t len = 0;
@@ -18,8 +17,8 @@ int check_pass(char *filename, uid_t user_id, char *password)
     {
         while (getline(&line, &len, f) != -1)
         {
-            uid = strtok(line, delim);
-            pwd = strtok(NULL, delim);
+            uid = strtok(line, ":");
+            pwd = strtok(NULL, ":");
             if (atoi(uid) == user_id)
             {
                 fclose(f);

question9/pwg.c

+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <pwd.h>
+
+#define SIZE 32
+
+int main(int argc, char *argv[])
+{
+    FILE *fsrc, *fdst;
+    char *lsrc = NULL;
+    char *ldst = NULL;
+    char *pwd;
+    char *uid;
+    char not_found = 1;
+    size_t len = 0;
+    ssize_t size;
+    char new_pwd[SIZE];
+    char old_pwd[SIZE];
+
+    uid_t user_id = getuid();
+
+    if ((fsrc = fopen("/home/admin/passwd", "r")) != NULL)
+    {
+        while (not_found && (size = getline(&lsrc, &len, fsrc)) != -1)
+        {
+            uid = strtok(lsrc, ":");
+            pwd = strtok(NULL, ":");
+        
+            if (atoi(uid) == user_id)
+                not_found = 0;
+        }
+        fclose(fsrc);
+    }
+
+    if (size != -1)
+    {
+        printf("Enter password: ");
+        fgets(old_pwd, SIZE, stdin);
+        printf("%s\n", old_pwd);
+
+        if (strcmp(pwd, crypt(old_pwd, "salt")))
+        {
+            fprintf(stderr, "Bad password\n");
+            free(lsrc);
+            return EXIT_FAILURE;
+        }
+        printf("Enter the new password: ");
+    }
+    else
+    {
+        printf("Enter password: ");
+    }
+
+    fgets(new_pwd, SIZE, stdin);
+    printf("%s\n", new_pwd);
+
+    if ((fsrc = fopen("/home/admin/passwd", "r")) != NULL && (fdst = fopen("/home/admin/passwd.tmp", "a")) != NULL)
+    {
+        while (getline(&ldst, &len, fsrc) != -1)
+        {
+            char *a = strtok(ldst, ":");
+            char *b = strtok(NULL, ":");
+
+            if (atoi(a) != user_id)
+                fprintf(fdst, "%s:%s:\n", a, b);
+        }
+        fprintf(fdst, "%d:%s:\n", user_id, crypt(new_pwd, "salt"));
+        free(ldst);
+        fclose(fsrc);
+        fclose(fdst);
+    }
+
+    printf("\n");
+    remove("/home/admin/passwd");
+    rename("/home/admin/passwd.tmp", "/home/admin/passwd");
+
+    return EXIT_SUCCESS;
+}

rendu.md

@@ -73,7 +73,7 @@ Pour cette question, on peut se servir de la précédente pour créer les utilis
 
 ## Question 9
 
-Le programme et les scripts dans le repertoire *question9*.
+Pour cette question, on ajoute aux données de la question précédente le fichier **pwg.c** qqui est une amélioration du fichier **rmg.c**.
 
 ## Question 10