/* FEATHERY FTP-Server
 * Copyright (C) 2005-2010 Andreas Martin (andreas.martin@linuxmail.org)
 * <https://sourceforge.net/projects/feathery>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef WIN32

#include <stdio.h>
#include <string.h>
#include <time.h>
#include <grp.h>
#include <pwd.h>
#include <sys/types.h>
#include <sys/stat.h>

#if defined(__APPLE__)
#include <sys/select.h>
#include <sys/time.h>
#endif

#include <unistd.h>

#if defined(__FreeBSD__)
#include <sys/uio.h>
#else
 //#include <sys/sendfile.h>
#endif

#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <dirent.h>
#include <arpa/inet.h>

#include "ftpTypes.h"
#include "ftpConfig.h"
#include "ftp.h"
#include "errno.h"

ip_t ownIp;

LOCAL fd_set watchedSockets;
LOCAL fd_set signaledSockets;
LOCAL int maxSockNr;


void ftpArchInit() {
	ownIp = 0;
	maxSockNr = 0;
	FD_ZERO(&watchedSockets);
	FD_ZERO(&signaledSockets);
}

void ftpArchCleanup(void) {
}

int ftpGetLocalTime(ftpTime_S *t) {
	struct tm *pTime;
	time_t tim;

	time(&tim);
	pTime = localtime(&tim);
	if (pTime) {
		t->year = (uint16_t) pTime->tm_year + 1900;
		t->month = (uint8_t) pTime->tm_mon + 1;
		t->day = (uint8_t) pTime->tm_mday;
		t->hour = (uint8_t) pTime->tm_hour;
		t->minute = (uint8_t) pTime->tm_min;
		t->second = (uint8_t) pTime->tm_sec;

		return 0;
	}

	return -1;
}

void* ftpOpenDir(const char* path) {
	return opendir(path);
}

const char* ftpReadDir(void* dirHandle) {
	struct dirent* dirEntry;

	dirEntry = readdir(dirHandle);
	if (dirEntry)
		return dirEntry->d_name;
	else
		return NULL;
}

int ftpCloseDir(void* dirHandle) {
	return closedir(dirHandle);
}

int ftpStat(const char* path, ftpPathInfo_S *info) {
	struct stat fileInfo = { 0 };
	struct tm *pTime;
	struct passwd *pw;
	struct group *gr;

	if (!stat(path, &fileInfo)) {
		if (S_ISREG(fileInfo.st_mode))
			info->type = TYPE_FILE;
		else if (S_ISDIR(fileInfo.st_mode))
			info->type = TYPE_DIR;
		else
			info->type = TYPE_LINK;

		pTime = localtime(&fileInfo.st_mtime);
		if (pTime) {
			info->mTime.year = (uint16_t) pTime->tm_year + 1900;
			info->mTime.month = (uint8_t) pTime->tm_mon + 1;
			info->mTime.day = (uint8_t) pTime->tm_mday;
			info->mTime.hour = (uint8_t) pTime->tm_hour;
			info->mTime.minute = (uint8_t) pTime->tm_min;
			info->mTime.second = (uint8_t) pTime->tm_sec;
		}
		pTime = localtime(&fileInfo.st_ctime);
		if (pTime) {
			info->cTime.year = (uint16_t) pTime->tm_year + 1900;
			info->cTime.month = (uint8_t) pTime->tm_mon + 1;
			info->cTime.day = (uint8_t) pTime->tm_mday;
			info->cTime.hour = (uint8_t) pTime->tm_hour;
			info->cTime.minute = (uint8_t) pTime->tm_min;
			info->cTime.second = (uint8_t) pTime->tm_sec;
		}
		pTime = localtime(&fileInfo.st_atime);
		if (pTime) {
			info->aTime.year = (uint16_t) pTime->tm_year + 1900;
			info->aTime.month = (uint8_t) pTime->tm_mon + 1;
			info->aTime.day = (uint8_t) pTime->tm_mday;
			info->aTime.hour = (uint8_t) pTime->tm_hour;
			info->aTime.minute = (uint8_t) pTime->tm_min;
			info->aTime.second = (uint8_t) pTime->tm_sec;
		}

		info->size = (uint32_t) fileInfo.st_size;
		info->links = (int) fileInfo.st_nlink;

		pw = getpwuid(fileInfo.st_uid);
		if (pw)
			strncpy(info->user, pw->pw_name, sizeof(info->user) - 1);
		else
			snprintf(info->user, 20, "%04d", fileInfo.st_uid);

		gr = getgrgid(fileInfo.st_gid);
		if (gr)
			strncpy(info->group, gr->gr_name, sizeof(info->group) - 1);
		else
			snprintf(info->group, 20, "%04d", fileInfo.st_gid);

		return 0;
	}

	return -1;
}

int ftpMakeDir(const char* path) {
	return mkdir(path, S_IRUSR | S_IWUSR);
}

int ftpRemoveDir(const char* path) {
	return rmdir(path);
}

int ftpCloseSocket(socket_t *s) {
	if (VERBOSE_MODE_ENABLED) printf("\nClosing socket: %d\n", *s);

	int ret = 0;
	if (*s > 0) {
		shutdown(*s, 2);
		ret = close(*s);
		*s = 0;
	}
	return ret;
}

int ftpSend(socket_t s, const void *data, int len) {
	int currLen = 0;

	do {
#if defined(__APPLE__) && defined(SO_NOSIGPIPE)
		currLen = send(s, data, len, SO_NOSIGPIPE);
#elif defined(MSG_NOSIGNAL)
		currLen = send(s, data, len, MSG_NOSIGNAL);
#else
		currLen = send(s, data, len, 0);
#endif

		if (currLen >= 0) {
			if (currLen == 0) {
				int errorNumber = getLastSocketError();
				const char *errText = getLastSocketErrorText(&errorNumber);
				if (VERBOSE_MODE_ENABLED) printf("\nERROR #1 ftpExecute ERROR ON SEND for socket = %d, data len = %d, error = %d [%s]\n", s, len, errorNumber, errText);
			}

			len -= currLen;
			data = (uint8_t*) data + currLen;
		} else {
			int errorNumber = getLastSocketError();
			const char *errText = getLastSocketErrorText(&errorNumber);
			if (VERBOSE_MODE_ENABLED) printf("\nERROR #2 ftpExecute ERROR ON SEND for socket = %d, data len = %d, currLen = %d, error = %d [%s]\n", s, len, currLen, errorNumber, errText);

			return -1;
		}

	} while (len > 0);

	return 0;
}

int ftpReceive(socket_t s, void *data, int len) {
	return recv(s, data, len, 0);
}

socket_t ftpEstablishDataConnection(int passive, ip_t *ip, port_t *port, int sessionId) {
	socket_t dataSocket;
	struct sockaddr_in clientAddr;
	struct sockaddr_in myAddr;
	int on = 1;
	unsigned len;
	dataSocket = socket(AF_INET, SOCK_STREAM, 0);
	if (dataSocket < 0)
		return -1;

	if (!passive) {
		if (setsockopt(dataSocket, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on))) {
			if (VERBOSE_MODE_ENABLED) printf("In ftpEstablishDataConnection #1 about to Close socket = %d, for sessionId = %d\n", dataSocket, sessionId);

			ftpUntrackSocket(dataSocket);
			ftpCloseSocket(&dataSocket);
			return -1;
		}
		myAddr.sin_family = AF_INET;
		myAddr.sin_addr.s_addr = INADDR_ANY;
		myAddr.sin_port = htons(20);
		myAddr.sin_zero[0] = 0;
		if (bind(dataSocket, (struct sockaddr *)&myAddr, sizeof(myAddr))) {
			if (VERBOSE_MODE_ENABLED) printf("In ftpEstablishDataConnection #2 about to Close socket = %d, for sessionId = %d\n", dataSocket, sessionId);

			ftpUntrackSocket(dataSocket);
			ftpCloseSocket(&dataSocket);
			return -1;
		}
		clientAddr.sin_family = AF_INET;
		clientAddr.sin_addr.s_addr = htonl(*ip);
		clientAddr.sin_port = htons(*port);
		clientAddr.sin_zero[0] = 0;

		if (connect(dataSocket, (struct sockaddr *)&clientAddr, sizeof(clientAddr))) {
			if (VERBOSE_MODE_ENABLED) printf("In ftpEstablishDataConnection #3 about to Close socket = %d, for sessionId = %d\n", dataSocket, sessionId);

			ftpUntrackSocket(dataSocket);
			ftpCloseSocket(&dataSocket);
			return -1;
		}
	} else {
		int passivePort = ftpGetPassivePort() + sessionId;
		if (VERBOSE_MODE_ENABLED) printf("\nPASSIVE CONNECTION for sessionId = %d using port #: %d for socket = %d\n", sessionId, passivePort, dataSocket);

		myAddr.sin_family = AF_INET;
		myAddr.sin_addr.s_addr = INADDR_ANY;
		myAddr.sin_port = htons(passivePort);
		myAddr.sin_zero[0] = 0;
		//myAddr.sin_port = htons(ftpGetPassivePort() + sessionId);

		if (setsockopt(dataSocket, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on))) {
			if (VERBOSE_MODE_ENABLED) printf("PASSIVE CONNECTION In ftpEstablishDataConnection setsockopt failed about to Close socket = %d, for sessionId = %d\n", dataSocket, sessionId);

			ftpUntrackSocket(dataSocket);
			ftpCloseSocket(&dataSocket);
			return -1;
		}

		if (bind(dataSocket, (struct sockaddr *)&myAddr, sizeof(myAddr))) {
			if (VERBOSE_MODE_ENABLED) printf("\nERROR In ftpEstablishDataConnection passive bind failed for sessionId = %d using port #: %d about to close socket = %d\n", sessionId, passivePort, dataSocket);

			ftpUntrackSocket(dataSocket);
			ftpCloseSocket(&dataSocket);
			return -1;
		}

		if (VERBOSE_MODE_ENABLED) printf("\nPASSIVE CONNECTION for sessionId = %d using port #: %d bound ok for socket = %d\n", sessionId, passivePort, dataSocket);

		len = sizeof(myAddr);
		if (getsockname(dataSocket, (struct sockaddr *)&myAddr, &len))             // Port des Server-Sockets ermitteln
		{
			if (VERBOSE_MODE_ENABLED) printf("\nERROR In ftpEstablishDataConnection passive getsockname failed for sessionId = %d using port #: %d about to close socket = %d\n", sessionId, passivePort, dataSocket);

			ftpUntrackSocket(dataSocket);
			ftpCloseSocket(&dataSocket);
			return -1;
		}

		*port = ntohs(myAddr.sin_port);
		*ip = ownIp;

		if (VERBOSE_MODE_ENABLED) printf("\nPASSIVE CONNECTION for sessionId = %d using port #: %d about to listen on port: %d using listener socket: %d\n", sessionId, passivePort, *port, dataSocket);

		if (listen(dataSocket, 100)) {
			if (VERBOSE_MODE_ENABLED) printf("\nERROR In ftpEstablishDataConnection passive listen failed for sessionId = %d using port #: %d about to close socket = %d\n", sessionId, passivePort, dataSocket);

			ftpUntrackSocket(dataSocket);
			ftpCloseSocket(&dataSocket);
			return -1;
		}

		//*port = ftpGetPassivePort();
		//*ip   = ownIp;
		//dataSocket = ftpGetServerPassivePortListenSocket();
	}
	return dataSocket;
}

socket_t ftpAcceptDataConnection(socket_t listner) {
	struct sockaddr_in clientinfo;
	unsigned len;
	socket_t dataSocket;

	len = sizeof(clientinfo);

	dataSocket = accept(listner, (struct sockaddr *)&clientinfo, &len);
	if (dataSocket < 0) {
		if (VERBOSE_MODE_ENABLED) printf("ERROR In ftpAcceptDataConnection accept failed, dataSocket = %d, listner = %d\n", dataSocket, listner);
		dataSocket = -1;
	} else {
		if (VERBOSE_MODE_ENABLED) printf("In ftpAcceptDataConnection accept new socket = %d, listner =%d\n", dataSocket, listner);
	}

	if (VERBOSE_MODE_ENABLED) printf("\nIn ftpAcceptDataConnection about to close listener socket = %d\n", listner);

	//ftpUntrackSocket(listner);
	//ftpCloseSocket(&listner); // Server-Socket wird nicht mehr gebrauch deshalb schließen

	ip_t remoteIP = ntohl(clientinfo.sin_addr.s_addr);
	if (ftpIsValidClient && ftpIsValidClient(remoteIP) == 0) {
		if (VERBOSE_MODE_ENABLED) printf("ERROR: Connection with %s is NOT a valid trusted client, dropping connection closing socket = %d.\n", inet_ntoa(clientinfo.sin_addr), dataSocket);

		ftpUntrackSocket(dataSocket);
		ftpCloseSocket(&dataSocket);
		dataSocket = -1;
	}

	return dataSocket;
}

socket_t ftpCreateServerSocket(int portNumber) {
	int	theServer;
	struct sockaddr_in serverinfo;
	unsigned len;
	int val = 1;
	int opt_result = 0;

	theServer = socket(AF_INET, SOCK_STREAM, 0);
	if (theServer < 0)
		return -1;

	serverinfo.sin_family = AF_INET;
	serverinfo.sin_addr.s_addr = INADDR_ANY;
	serverinfo.sin_port = htons(portNumber);
	serverinfo.sin_zero[0] = 0;
	len = sizeof(serverinfo);

	opt_result = setsockopt(theServer, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));

	if (bind(theServer, (struct sockaddr *)&serverinfo, len)) {
		if (VERBOSE_MODE_ENABLED) printf("\nERROR In ftpCreateServerSocket bind FAILED about to close listener socket = %d opt_result = %d\n", theServer, opt_result);

		ftpUntrackSocket(theServer);
		ftpCloseSocket(&theServer);
		return -2;
	}

	if (listen(theServer, 100)) {
		if (VERBOSE_MODE_ENABLED) printf("\nERROR In ftpCreateServerSocket listen FAILED about to close listener socket = %d\n", theServer);

		ftpUntrackSocket(theServer);
		ftpCloseSocket(&theServer);
		return -3;
	}

	return (socket_t) theServer;
}

socket_t ftpAcceptServerConnection(socket_t server, ip_t *remoteIP, port_t *remotePort) {
	struct sockaddr_in sockinfo;
	socket_t clientSocket;
	unsigned len;

	len = sizeof(sockinfo);

	clientSocket = accept(server, (struct sockaddr *)&sockinfo, &len);

	if (clientSocket < 0) {
		if (VERBOSE_MODE_ENABLED) printf("ftpAcceptServerConnection accept failed for socket = %d\n", clientSocket);
	} else {
		if (VERBOSE_MODE_ENABLED) printf("ftpAcceptServerConnection accept new socket = %d\n", clientSocket);
	}

	*remoteIP = ntohl(sockinfo.sin_addr.s_addr);
	*remotePort = ntohs(sockinfo.sin_port);

	if (!ownIp)	// kennen wir schon die eigene IP?
	{
		len = sizeof(sockinfo);
		if (clientSocket >= 0 && getsockname(clientSocket, (struct sockaddr *)&sockinfo, &len)) {
			if (VERBOSE_MODE_ENABLED) printf("getsockname error\n");
		}

		ownIp = ntohl(sockinfo.sin_addr.s_addr);        // eigene IP-Adresse abspeichern (wird dir PASV benätigt)
	}

	if (VERBOSE_MODE_ENABLED) printf("Connection with %s on Port %d accepted.\n", inet_ntoa(sockinfo.sin_addr), *remotePort);

	if (ftpIsValidClient && ftpIsValidClient(*remoteIP) == 0) {
		if (VERBOSE_MODE_ENABLED) printf("Connection with %s on Port %d is NOT a valid trusted client, dropping connection closing socket = %d.\n", inet_ntoa(sockinfo.sin_addr), *remotePort, clientSocket);

		ftpUntrackSocket(clientSocket);
		ftpCloseSocket(&clientSocket);
		clientSocket = -1;
	}

	return clientSocket;
}

int ftpTrackSocket(socket_t s) {
	if (s > maxSockNr)
		maxSockNr = s;
	FD_SET(s, &watchedSockets);
	return 0;
}

int ftpUntrackSocket(socket_t s) {
	if (s > 0) {
		FD_CLR(s, &watchedSockets);
	}
	return 0;
}

int ftpTestSocket(socket_t s) {
	return FD_ISSET(s, &signaledSockets);
}

int ftpSelect(int poll) {
	signaledSockets = watchedSockets;

	if (poll) {
		struct timeval t = { 0 };
		//t.tv_usec = 100;
		return select(maxSockNr + 1, &signaledSockets, NULL, NULL, &t);
	} else {
		struct timeval t = { 0 };
		t.tv_usec = 1000;

		return select(maxSockNr + 1, &signaledSockets, NULL, NULL, &t);
	}
}

int getLastSocketError() {
	return errno;
}

const char * getLastSocketErrorText(int *errNumber) {
	int errId = (errNumber != NULL ? *errNumber : getLastSocketError());
	return strerror(errId);
}


#endif