Add log file and password policy

1 files changed, 127 insertions, 17 deletions

diff --git a/main.c b/main.c
index c12f0af..aa840b4 100644
--- a/main.c
+++ b/main.c
@@ -1,29 +1,125 @@
 // TODO: Secret stored in memory must be encrypted with a key derived from the
 // user password or consider making password manager stateless (no passwords
 // stored locally)
-// TODO: Replace CBC with GCM or CCM to prevent padding attacks
-// TODO: Have ascii art of a cerberus on start menu/page
 
 #include "main.h"
 
 struct Password passwords[MAX_PASSWORDS];
 int numPasswords = 0;
 
+FILE *log_file;
+
+void log_message(const char *message) {
+  if (log_file == NULL) {
+    printf("Error: Log file not available.\n");
+    return;
+  }
+
+  time_t current_time;
+  struct tm *time_info;
+  char time_string[80];
+
+  time(&current_time);
+  time_info = localtime(&current_time);
+
+  strftime(time_string, sizeof(time_string), "[%Y-%m-%d %H:%M:%S] ", time_info);
+  fprintf(log_file, "%s %s\n", time_string,
+          message); // Print timestamp and message
+}
+
+void initialize_log() {
+  log_file = fopen("cerberus.log", "a");
+  if (log_file == NULL) {
+    printf("Error: Could not open log file.\n");
+  } else {
+    log_message("=== cerberus log ==="); // Initial log message
+  }
+}
+
+void close_log() {
+  if (log_file != NULL) {
+    fclose(log_file);
+  }
+}
+
+void error_exit(const char *error_message) {
+  log_message(error_message);
+  if (log_file != NULL) {
+    fclose(log_file);
+  }
+  exit(1);
+}
+
+void clear_input_buffer() {
+  int c;
+  while ((c = getchar()) != '\n' && c != EOF)
+    ;
+}
+
+void check_password_policy(const char *password) {
+  int length = strlen(password);
+  if (length < 8) {
+    error_exit("Password must be at least 8 characters long.");
+  }
+
+  bool has_upper = false, has_lower = false, has_digit = false,
+       has_special = false;
+  for (int i = 0; i < length; i++) {
+    if (isupper(password[i])) {
+      has_upper = true;
+    } else if (islower(password[i])) {
+      has_lower = true;
+    } else if (isdigit(password[i])) {
+      has_digit = true;
+    } else {
+      has_special = true;
+    }
+  }
+
+  if (!has_upper || !has_lower || !has_digit || !has_special) {
+    error_exit("Password must contain at least one uppercase letter, one "
+               "lowercase letter, one digit, and one special character.");
+  }
+}
+
 void generate_password(char *password, int length) {
-  // Define the character set for the password
+  if (length < 8 || length > MAX_PASSWORD_LENGTH - 1) {
+    printf("Invalid password length. Please enter a length between 8 and %d.\n",
+           MAX_PASSWORD_LENGTH - 1);
+    return;
+  }
+
   char charset[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456"
-                   "789!@#$%^&*-_=+{}[]|;:',.<>/?";
+                   "789!@#$%^&*()-_=+[]{}|;:',.<>?";
   int charset_size = strlen(charset);
 
-  // Seed the random number generator
   srand(time(NULL));
 
-  for (int i = 0; i < length; i++) {
-    int index = rand() % charset_size;
-    password[i] = charset[index];
+  // Initialize flags to check if each required character type is included
+  bool has_upper = false, has_lower = false, has_digit = false,
+       has_special = false;
+
+  // Create password with at least one character from each required type
+  password[0] = charset[rand() % 26];      // at least one uppercase letter
+  password[1] = charset[26 + rand() % 26]; // at least one lowercase letter
+  password[2] = charset[52 + rand() % 10]; // at least one digit
+  password[3] = charset[62 + rand() % 14]; // at least one special character
+
+  // Fill the rest of the password randomly from the character set
+  for (int i = 4; i < length; i++) {
+    password[i] = charset[rand() % charset_size];
   }
 
   password[length] = '\0';
+
+  // Shuffle the password characters
+  for (int i = 0; i < length; i++) {
+    int j = rand() % length;
+    char temp = password[i];
+    password[i] = password[j];
+    password[j] = temp;
+  }
+
   printf("Generated Password: %s\n", password);
 }
 
@@ -221,6 +317,8 @@ void print_ascii_art(const char *filename) {
 }
 
 int main() {
+  initialize_log();
+
   const char *dir = "tmp"; // Directory to store password files
   mkdir(dir, 0700);        // Create directory if it doesn't exist
 
@@ -266,25 +364,33 @@ int main() {
     printf("3. Exit\n");
     printf("Enter your choice: ");
     scanf("%d", &choice);
+    clear_input_buffer(); // Clear input buffer after scanf
 
     switch (choice) {
     case 1: {
-      if (numPasswords >= MAX_PASSWORDS) {
-        printf("Maximum number of passwords reached.\n");
-        break;
-      }
       struct Password password;
       int length;
-      printf("Enter password length: ");
-      scanf("%d", &length);
+      do {
+        printf("Enter password length: ");
+        scanf("%d", &length);
+        clear_input_buffer();
+        if (length < 8 || length > MAX_PASSWORD_LENGTH - 1) {
+          printf("Invalid password length. Please enter a length between 8 and "
+                 "%d.\n",
+                 MAX_PASSWORD_LENGTH - 1);
+        }
+      } while (length < 8 || length > MAX_PASSWORD_LENGTH - 1);
       generate_password(password.password, length);
       printf("Enter website: ");
-      scanf("%s", password.website);
+      fgets(password.website, sizeof(password.website), stdin);
+      password.website[strcspn(password.website, "\n")] =
+          0; // Remove newline character
       printf("Enter username: ");
-      scanf("%s", password.username);
+      fgets(password.username, sizeof(password.username), stdin);
+      password.username[strcspn(password.username, "\n")] =
+          0; // Remove newline character
       save_password(&password, password.website, dir, user_password);
       printf("Password information saved to %s\n", password.website);
-      passwords[numPasswords++] = password;
       break;
     }
     case 2: {
@@ -292,6 +398,7 @@ int main() {
       printf("Enter the number of the password to copy (0 to cancel): ");
       int selection;
       scanf("%d", &selection);
+      clear_input_buffer();
       if (selection > 0 && selection <= numPasswords) {
         struct Password selected_password = passwords[selection - 1];
         printf("Selected Password:\n");
@@ -302,6 +409,7 @@ int main() {
                "cancel): ");
         int copy_choice;
         scanf("%d", &copy_choice);
+        clear_input_buffer();
         switch (copy_choice) {
         case 1:
           copy_to_clipboard(selected_password.password);
@@ -319,11 +427,13 @@ int main() {
     }
     case 3:
       printf("Exiting program...\n");
+      close_log();
       return 0;
     default:
       printf("Invalid choice. Please enter 1, 2, or 3.\n");
     }
   }
 
+  close_log();
   return 0;
 }