A

1 files changed, 398 insertions, 0 deletions

diff --git a/src/util.cpp b/src/util.cpp
new file mode 100644
index 0000000..142fcbd
--- /dev/null
+++ b/src/util.cpp
@@ -0,0 +1,398 @@
+#include <string>
+#include <string.h>
+#include <cstddef>
+#include <stdio.h>
+#include <stdarg.h>
+#include <time.h>
+#include <sys/timeb.h>
+
+#include "util.hpp"
+
+#define VALID_CHARACTERS "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+
+enum Command parse_command(char* line){
+  /* Find a valid command in the first word of the line (case sensitive)
+  args:
+    line (char*): string of characters from the input file
+
+  returns:
+    (command): Returns the found command. Returns else if first word is invalid.
+  */
+  if (line == NULL){
+    return INVALID;
+  }
+
+  char* rest;
+  char* tok = strtok_r(line, " ", &rest);
+
+  if (tok == NULL){
+    return INVALID;
+  }
+
+  // REGISTER [username] [password]
+  if (strcmp(tok, "REGISTER") == 0){
+    char* username = strtok_r(rest, " ", &rest);
+    if(!isValidUsername(username)) return INVALID;
+
+    char* password = strtok_r(rest, " ", &rest);
+    if(password == NULL) return INVALID;
+    if(!isValidPassword(password)) return INVALID;
+
+    char* misc = strtok_r(rest, " ", &rest);
+    if(misc != NULL) return INVALID;
+
+    return REGISTER;
+  }
+
+  // LOGIN [username] [password]
+  if (strcmp(tok, "LOGIN") == 0){
+    char* username = strtok_r(rest, " ", &rest);
+    if(!isValidUsername(username)) return INVALID;
+
+    char* password = strtok_r(rest, " ", &rest);
+    if(password == NULL) return INVALID;
+    if(!isValidPassword(password)) return INVALID;
+
+    char* misc = strtok_r(rest, " ", &rest);
+    if(misc != NULL) return INVALID;
+
+    return LOGIN;
+  }
+
+  // LOGOUT
+  if (strcmp(tok, "LOGOUT") == 0){
+    char* misc = strtok_r(rest, " ", &rest);
+    if(misc != NULL) return INVALID;
+
+    return LOGOUT;
+  }
+
+  // SEND [msg]
+  if (strcmp(tok, "SEND") == 0){
+    if (int(strlen(rest) == 0)) return INVALID;
+
+    return SEND;
+  }
+
+  // SEND2 [username] [msg]
+  if (strcmp(tok, "SEND2") == 0){
+    char* username = strtok_r(rest, " ", &rest);
+    if(!isValidUsername(username)) return INVALID;
+
+    if (int(strlen(rest) == 0)) return INVALID;
+
+    return SEND2;
+  }
+
+  // SENDA [msg]
+  if (strcmp(tok, "SENDA") == 0){
+    if (int(strlen(rest) == 0)) return INVALID;
+
+    return SENDA;
+  }
+
+  // SENDA2 [username] [msg]
+  if (strcmp(tok, "SENDA2") == 0){
+    char* username = strtok_r(rest, " ", &rest);
+    if(!isValidUsername(username)) return INVALID;
+
+    if (int(strlen(rest) == 0)) return INVALID;
+
+    return SENDA2;
+  }
+
+  // SENDF [local file]
+  if (strcmp(tok, "SENDF") == 0){
+    char* file_name = strtok_r(rest, " ", &rest);
+    if(file_name == NULL) return INVALID;
+
+    if (int(strlen(rest) != 0)) return INVALID;
+
+    return SENDF;
+  }
+
+  // SENDF2 [username] [local file]
+  if (strcmp(tok, "SENDF2") == 0){
+    char* username = strtok_r(rest, " ", &rest);
+    if(!isValidUsername(username)) return INVALID;
+
+    char* file_name = strtok_r(rest, " ", &rest);
+    if(file_name == NULL) return INVALID;
+
+    if (int(strlen(rest) != 0)) return INVALID;
+
+    return SENDF2;
+  }
+
+  // LIST
+  if (strcmp(tok, "LIST") == 0){
+    char* misc = strtok_r(rest, " ", &rest);
+    if(misc != NULL) return INVALID;
+
+    return LIST;
+  }
+
+  // DELAY
+  if (strcmp(tok, "DELAY") == 0){
+    char* delay_time = strtok_r(rest, " ", &rest);
+    if(delay_time == NULL) return INVALID;
+
+    std::string str(delay_time);
+    std::size_t found = str.find_first_not_of("0123456789");
+    if(found != std::string::npos) return INVALID;
+
+    if (int(strlen(rest) != 0)) return INVALID;
+
+    return DELAY;
+  }
+
+  // default
+  return INVALID;
+}
+
+
+bool isValidUsername(char* username){
+  /* Helper function to check if a username string is valid
+  args:
+    username (char*): Username to be tested.
+
+  returns:
+    bool: Username is valid ? true, false
+  */
+  if(username == NULL) return false;
+  else if ((strlen(username) > MAX_USERNAME_LEN)||(strlen(username) < MIN_USERNAME_LEN)) return false;
+  else{
+    std::string str(username);
+    std::size_t found = str.find_first_not_of(VALID_CHARACTERS);
+    if(found != std::string::npos) return false;
+  }
+
+  return true;
+}
+
+
+bool isValidPassword(char* password){
+  if(password == NULL) return false;
+  else if ((strlen(password) > MAX_PASSWORD_LEN)||(strlen(password) < MIN_PASSWORD_LEN)) return false;
+  else{
+    std::string str(password);
+    std::size_t found = str.find_first_not_of(VALID_CHARACTERS);
+    if(found != std::string::npos) return false;
+  }
+
+  return true;
+}
+
+
+void Error(const char * format, ...) {
+	char msg[4096];
+	va_list argptr;
+	va_start(argptr, format);
+	vsprintf(msg, format, argptr);
+	va_end(argptr);
+	fprintf(stderr, "Error: %s\n", msg);
+	exit(-1);
+}
+
+void Log(const char * format, ...) {
+	char msg[2048];
+	va_list argptr;
+	va_start(argptr, format);
+	vsprintf(msg, format, argptr);
+	va_end(argptr);
+	fprintf(stderr, "%s\n", msg);
+}
+
+// convert buf[0:3] to int
+void buf2i(BYTE * buf, int &i){
+  // No way to avoid Segmentation fault. Some bytes may be 0
+  i = 0;
+  i += buf[3];
+  i += ((int)(buf[2])) << 8;
+  i += ((int)(buf[1])) << 16;
+  i += ((int)(buf[0])) << 24;
+}
+
+// convert int to buf[4] where buf[0] contains MSB's and buf[3] contains LSB's
+void i2buf(int &i, BYTE * buf){
+  // No way to avoid Segmentation fault. Some bytes may be 0
+  buf[0] = (BYTE)((i & 0xFF000000) >> 24);
+  buf[1] = (BYTE)((i & 0x00FF0000) >> 16);
+  buf[2] = (BYTE)((i & 0x0000FF00) >> 8);
+  buf[3] = (BYTE)(i & 0x000000FF);
+}
+
+const char * com2str(enum Command command){
+  const char * com2str[] = {"REGISTER",
+                            "LOGIN",
+                            "LOGOUT",
+                            "SEND",
+                            "SEND2",
+                            "SENDA",
+                            "SENDA2",
+                            "SENDF",
+                            "SENDF2",
+                            "LIST",
+                            "DELAY",
+                            "GETF",
+                            "PING",
+                            "CONNECT",
+                            "",
+                            "INVALID"
+                          };
+    return com2str[command];
+}
+
+// Computes the difference between times a and b in seconds
+// a - b = result
+double timeDifference(struct timeb a, struct timeb b){
+  return (a.time + a.millitm / (double) 1000.0f) - (b.time + b.millitm / (double) 1000.0f);
+}
+
+int getNumEntries(const char* database){
+  FILE* fp = fopen(database, "r");
+  if (!fp){
+    Log("Username check failed to open the file: %s", database);
+    return -1;
+  }
+
+  int numEntries = 0;
+
+  char line[LINE_SIZE] = {0};
+  while(fgets(line, LINE_SIZE, fp) != NULL){
+    char* new_line_pos = strchr(line, '\n');
+    if(new_line_pos != NULL)
+      *new_line_pos = 0;
+    // Including blank lines as entries. Don't use any blank lines.
+    numEntries++;
+    memset(line, 0, LINE_SIZE);
+  }
+
+  fclose(fp);
+  return numEntries;
+}
+
+// User/password is in registry: true
+// User/password is not in registry: false
+bool loginQuery(const char * database, char* username, char* password){
+  FILE* fp = fopen(database, "r");
+  if (!fp){
+    Log("Registry check failed to open the file: %s", database);
+    return false;
+  }
+
+  char line[LINE_SIZE] = {0};
+  while(fgets(line, LINE_SIZE, fp) != NULL){
+    char* new_line_pos = strchr(line, '\n');
+    if(new_line_pos != NULL)
+      *new_line_pos = 0;
+
+    char* rest;
+    char* usr = strtok_r(line, " ", &rest);
+    char* pswd = strtok_r(rest, " ", &rest);
+
+    //Log("username: |%s|   Password: |%s|", usr, pswd);
+
+    if((strcmp(username, usr) == 0) && (strcmp(password, pswd) == 0)){
+      fclose(fp);
+      return true;
+    }
+
+    memset(line, 0, LINE_SIZE);
+  }
+
+  fclose(fp);
+  return false;
+}
+
+// User is in registry: true
+// User is not in registry: false
+bool usernameQuery(const char * database, char* username){
+  FILE* fp = fopen(database, "r");
+  if (!fp){
+    Log("Username check failed to open the file: %s", database);
+    return false;
+  }
+
+  char line[LINE_SIZE] = {0};
+  while(fgets(line, LINE_SIZE, fp) != NULL){
+    char* new_line_pos = strchr(line, '\n');
+    if(new_line_pos != NULL)
+      *new_line_pos = 0;
+
+    char* rest;
+    char* usr = strtok_r(line, " ", &rest);
+
+    //Log("username: |%s|", usr);
+
+    if(strcmp(username, usr) == 0){
+      fclose(fp);
+      return true;
+    }
+
+    memset(line, 0, LINE_SIZE);
+  }
+
+  fclose(fp);
+  return false;
+}
+
+void recordEntry(const char * database, char* key, char* value){
+  FILE* fp = fopen(database, "a");
+
+  if (!fp){
+    Log("Registry append failed to open the file: %s", database);
+    return;
+  }
+
+  char line[LINE_SIZE] = {0};
+  strcat(line, key);
+  strcat(line, " ");
+  strcat(line, value);
+  strcat(line, "\n");
+
+  fputs(line, fp);
+  fclose(fp);
+}
+
+void clearDatabase(const char * database){
+  FILE* fp = fopen(database, "w");
+  fclose(fp);
+}
+
+
+int buf2file(BYTE* buf, int nbytes, char* filename){
+  FILE* f = fopen(filename, "w");
+  if(!f) return -1;
+
+  fwrite(buf, 1, nbytes, f);
+  fclose(f);
+  return 0;
+}
+
+
+int file2buf(char* filename, BYTE* buf){
+  FILE* f = fopen(filename, "r");
+  if(!f){
+    Log("Error: Cannot open %s", filename);
+    return -1;
+  }
+
+  fseek(f, 0, SEEK_END);  // jump to end of file
+  long nbytes = ftell(f);  // find current offset on file f
+  fseek(f, 0, SEEK_SET);  // jump to beginning of file
+
+  if(nbytes > MAX_REQUEST_SIZE){
+    Log("Error: File %s is too big: %d", filename, nbytes);
+    return -1;
+  }
+
+  int nread = fread(buf, 1, nbytes, f);
+  if(nread != nbytes){
+    Log("Error: Byte count mismatch with fread: %d, %d", nbytes, nread);
+    return -1;
+  }
+
+  fclose(f);
+  return nbytes;
+}