/*************************************************************************
 * (C) 2010 AITNET - Sofia/Bulgaria - <office@aitbg.com>
 *  by Michael Pounov <misho@aitbg.com>
 *
 * $Author: misho $
 * $Id: upd.c,v 1.3 2012/07/22 22:46:48 misho Exp $
 *
 *************************************************************************
The ELWIX and AITNET software is distributed under the following
terms:

All of the documentation and software included in the ELWIX and AITNET
Releases is copyrighted by ELWIX - Sofia/Bulgaria <info@elwix.org>

Copyright 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
	by Michael Pounov <misho@elwix.org>.  All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
   must display the following acknowledgement:
This product includes software developed by Michael Pounov <misho@elwix.org>
ELWIX - Embedded LightWeight unIX and its contributors.
4. Neither the name of AITNET nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
*/
#include "global.h"
#include "upd.h"


int Kill;


static inline int ChkImg(const char *csImg, char *psDir)
{
	int res = 0;

	getcwd(psDir, MAXPATHLEN);
	if (access(csImg, R_OK) == -1) {
		printf("Error:: Unable to find new image %s #%d - %s\n", 
				csImg, errno, strerror(errno));
		res = -1;
	} else {
		strlcat(psDir, "/", MAXPATHLEN);
		strlcat(psDir, csImg, MAXPATHLEN);
	}

	return res;
}

// -------------------------------

int Activate(const char *csImg)
{
	char szDir[MAXPATHLEN];

	if (ChkImg(csImg, szDir) == -1)
		return -1;

	VERB(3) printf("Activate procedure for %s\n", szDir);

	unlink(FIRMWARE_IMG);
	if (symlink(szDir, FIRMWARE_IMG) == -1) {
		printf("Error:: Unable to activate new image %s #%d - %s\n", 
				csImg, errno, strerror(errno));
		return -2;
	}

	syslog(LOG_NOTICE, "Activate new image %s", csImg);
	VERB(1) printf("Activate new image %s\n", csImg);
	return 0;
}

int Install(const char *csImg, const char *psDir)
{
	int src, dst, len;
	u_char buf[BUFSIZ];
	char szDir[MAXPATHLEN], szFile[MAXPATHLEN];
	struct stat ss, ds;

	strlcpy(szFile, psDir, MAXPATHLEN);
	strlcat(szFile, "/", MAXPATHLEN);
	strlcat(szFile, csImg, MAXPATHLEN);
	if (access(szFile, R_OK) == -1) {
		printf("Error:: Unable to find new image %s #%d - %s\n", 
				csImg, errno, strerror(errno));
		return -1;
	} else {
		memset(&ss, 0, sizeof ss);
		if (stat(szFile, &ss) == -1) {
			printf("Error:: Unable to find new image %s #%d - %s\n", 
					csImg, errno, strerror(errno));
			return -1;
		}
	}

	getcwd(szDir, MAXPATHLEN);
	VERB(3) printf("Install procedure from %s to %s\n", szFile, szDir);
	strlcat(szDir, "/", MAXPATHLEN);
	strlcat(szDir, csImg, MAXPATHLEN);
	memset(&ds, 0, sizeof ds);
	if (stat(szDir, &ds) == -1 && ENOENT != errno) {
		printf("Error:: Unable to stat target #%d - %s\n", 
				errno, strerror(errno));
		return -1;
	}

	if (ss.st_dev == ds.st_dev && ss.st_ino == ds.st_ino) {
		printf("Error:: Unable to install into self ...\n");
		return -1;
	}

	dst = open(szDir, O_WRONLY | O_CREAT | O_TRUNC, 0644);
	if (dst == -1) {
		printf("Error:: in create image %s #%d - %s\n", 
				szDir, errno, strerror(errno));
		return -1;
	}
	src = open(szFile, O_RDONLY);
	if (src == -1) {
		printf("Error:: in open image %s #%d - %s\n", 
				szFile, errno, strerror(errno));
		close(dst);
		unlink(szDir);
		return -1;
	}

	while ((len = read(src, buf, BUFSIZ)) > 0)
		if (write(dst, buf, len) == -1) {
			printf("Error:: in write image #%d - %s\n", 
					errno, strerror(errno));
			close(src);
			close(dst);
			unlink(szDir);

			len = -1;
			break;
		}

	close(src);
	close(dst);

	if (!len) {
		syslog(LOG_NOTICE, "Install image %s to %s", csImg, szDir);
		VERB(1) printf("Install image %s to %s\n", csImg, szDir);
	}
	return len;
}

int Rollback(const char *csImg)
{
	int src, dst, len;
	u_char buf[BUFSIZ];
	char szDir[MAXPATHLEN], szFile[MAXPATHLEN];
	struct stat ss, ds;

	getcwd(szFile, MAXPATHLEN);
	strlcat(szFile, "/", MAXPATHLEN);
	strlcat(szFile, FIRMWARE_BAK, MAXPATHLEN);
	if (access(szFile, R_OK) == -1) {
		printf("Error:: Unable to find backup image #%d - %s\n", 
				errno, strerror(errno));
		return -1;
	} else {
		memset(&ss, 0, sizeof ss);
		if (stat(szFile, &ss) == -1) {
			printf("Error:: Unable to find backup image #%d - %s\n", 
					errno, strerror(errno));
			return -1;
		}
	}

	getcwd(szDir, MAXPATHLEN);
	strlcat(szDir, "/", MAXPATHLEN);
	strlcat(szDir, csImg, MAXPATHLEN);
	VERB(3) printf("Rollback procedure for image %s from backup!\n", csImg);
	memset(&ds, 0, sizeof ds);
	if (stat(szDir, &ds) == -1 && ENOENT != errno) {
		printf("Error:: Unable to stat target #%d - %s\n", 
				errno, strerror(errno));
		return -1;
	}

	if (ss.st_dev == ds.st_dev && ss.st_ino == ds.st_ino) {
		printf("Error:: Unable to rollback into self ...\n");
		return -1;
	}

	src = open(szFile, O_RDONLY);
	if (src == -1) {
		printf("Error:: in open backup %s #%d - %s\n", 
				szFile, errno, strerror(errno));
		return -1;
	}
	dst = open(szDir, O_WRONLY | O_CREAT | O_TRUNC, 0644);
	if (dst == -1) {
		printf("Error:: in create image %s #%d - %s\n", 
				szDir, errno, strerror(errno));
		close(src);
		return -1;
	}

	while ((len = read(src, buf, BUFSIZ)) > 0)
		if (write(dst, buf, len) == -1) {
			printf("Error:: in write image #%d - %s\n", 
					errno, strerror(errno));
			close(dst);
			close(src);
			unlink(szDir);

			len = -1;
			break;
		}

	close(dst);
	close(src);

	if (!len) {
		syslog(LOG_NOTICE, "Rollback image %s to %s", csImg, szDir);
		VERB(1) printf("Rollback image %s to %s\n", csImg, szDir);
	}
	return len;

	return 0;
}

int tFTP(const char *csImg, const char *psDir)
{
	int src, dst, len;
	u_char buf[BUFSIZ];
	char szDir[MAXPATHLEN], szFile[MAXPATHLEN];
	struct stat ss, ds;

	if (ChkImg(csImg, szDir) == -1)
		return -1;
	else {
		memset(&ss, 0, sizeof ss);
		if (stat(szDir, &ss) == -1) {
			printf("Error:: Unable to find image %s #%d - %s\n", 
					szDir, errno, strerror(errno));
			return -1;
		}
	}

	VERB(3) printf("tFTP procedure for %s to %s\n", szDir, psDir);
	strlcpy(szFile, psDir, MAXPATHLEN);
	strlcat(szFile, "/", MAXPATHLEN);
	strlcat(szFile, csImg, MAXPATHLEN);
	memset(&ds, 0, sizeof ds);
	if (stat(szFile, &ds) == -1 && ENOENT != errno) {
		printf("Error:: Unable to stat target %s #%d - %s\n", 
				szFile, errno, strerror(errno));
		return -1;
	}

	if (ss.st_dev == ds.st_dev && ss.st_ino == ds.st_ino) {
		printf("Error:: Unable to copy into self ...\n");
		return -1;
	}

	dst = open(szFile, O_WRONLY | O_CREAT | O_TRUNC, 0644);
	if (dst == -1) {
		printf("Error:: in create backup %s #%d - %s\n", 
				szFile, errno, strerror(errno));
		return -1;
	}
	src = open(szDir, O_RDONLY);
	if (src == -1) {
		printf("Error:: in open image %s #%d - %s\n", 
				szDir, errno, strerror(errno));
		close(dst);
		unlink(szFile);
		return -1;
	}

	while ((len = read(src, buf, BUFSIZ)) > 0)
		if (write(dst, buf, len) == -1) {
			printf("Error:: in write backup #%d - %s\n", 
					errno, strerror(errno));
			close(src);
			close(dst);
			unlink(szFile);

			len = -1;
			break;
		}

	close(src);
	close(dst);

	if (!len) {
		syslog(LOG_NOTICE, "Export tFTP image %s to %s", csImg, psDir);
		VERB(1) printf("Export tFTP image %s to %s\n", csImg, psDir);
	}
	return len;
}

int Backup(const char *csImg)
{
	int src, dst, len;
	u_char buf[BUFSIZ];
	char szDir[MAXPATHLEN], szFile[MAXPATHLEN];

	if (ChkImg(csImg, szDir) == -1)
		return -1;

	getcwd(szFile, MAXPATHLEN);
	strlcat(szFile, "/", MAXPATHLEN);
	strlcat(szFile, FIRMWARE_BAK, MAXPATHLEN);
	VERB(3) printf("Backup procedure for %s\n", szDir);

	dst = open(szFile, O_WRONLY | O_CREAT | O_TRUNC, 0644);
	if (dst == -1) {
		printf("Error:: in create backup %s #%d - %s\n", 
				szFile, errno, strerror(errno));
		return -1;
	}
	src = open(szDir, O_RDONLY);
	if (src == -1) {
		printf("Error:: in open image %s #%d - %s\n", 
				szDir, errno, strerror(errno));
		close(dst);
		unlink(szFile);
		return -1;
	}

	while ((len = read(src, buf, BUFSIZ)) > 0)
		if (write(dst, buf, len) == -1) {
			printf("Error:: in write backup #%d - %s\n", 
					errno, strerror(errno));
			close(src);
			close(dst);
			unlink(szFile);

			len = -1;
			break;
		}

	close(src);
	close(dst);

	if (!len) {
		syslog(LOG_NOTICE, "Backup image %s", csImg);
		VERB(1) printf("Backup image %s\n", csImg);
	}
	return len;
}

int Clean(const char *csImg)
{
	char szDir[MAXPATHLEN], szFile[MAXPATHLEN];

	if (ChkImg(csImg, szDir) == -1)
		return -1;

	getcwd(szFile, MAXPATHLEN);
	strlcat(szFile, "/", MAXPATHLEN);
	strlcat(szFile, FIRMWARE_BAK, MAXPATHLEN);

	VERB(3) printf("Clean procedure for %s\n", szDir);

	if (unlink(szFile) == -1) {
		printf("Error:: in clean backup #%d - %s\n", errno, strerror(errno));
		return -1;
	}

	syslog(LOG_NOTICE, "Clean backup for image %s", csImg);
	VERB(1) printf("Clean backup for image %s\n", csImg);
	return 0;
}

// ----------------------------------

static void Signal(int sig)
{
	int stat;

	switch (sig) {
		case SIGHUP:
			VERB(5) printf("Info(5):: Signal arrived #%d\n", sig);
			break;
		case SIGCHLD:
			while (waitpid(-1, &stat, WNOHANG) > 0);
			break;
		case SIGTERM:
			Kill = 1;
			VERB(5) printf("Info(5):: Signal arrived #%d\n", sig);
			break;
	}
}

int Daemonize(struct sockaddr_in sin, const char *csTFTP)
{
	int s, n = 1;
	pid_t pid;
	fd_set rfd;
	u_short seq = 0xffff;
	int clilen, len, f, retry;
	struct sockaddr_in cli, rcv;
	struct sigaction sa;
	u_char buf[TFTP_BUF], *pos;
	char szFName[MAX_STR];
	struct tftphdr *tftp = (struct tftphdr*) buf;
	struct timeval tv = { TFTP_TIMEOUT, 0 };

	VERB(3) printf("Daemonize procedure for %s:%d to %s\n", 
			inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), csTFTP);

	memset(&sa, 0, sizeof sa);
	sigemptyset(&sa.sa_mask);
	sa.sa_handler = Signal;
	sigaction(SIGCHLD, &sa, NULL);
	sigaction(SIGTERM, &sa, NULL);
	sigaction(SIGHUP, &sa, NULL);

	s = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
	if (s == -1) {
		printf("Error:: in create socket #%d - %s\n", errno, strerror(errno));
		return -1;
	}
	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &n, sizeof n) == -1) {
		printf("Error:: in socket options #%d - %s\n", errno, strerror(errno));
		close(s);
		return -1;
	}
	if (bind(s, (struct sockaddr*) &sin, sizeof sin) == -1) {
		printf("Error:: in bind #%d - %s\n", errno, strerror(errno));
		close(s);
		return -1;
	}

	switch ((pid = fork())) {
		case -1:
			printf("Error:: in socket options #%d - %s\n", errno, strerror(errno));
			close(s);
			return -1;
		case 0:
			setsid();

			while (!Kill) {
				FD_ZERO(&rfd);
				FD_SET(s, &rfd);
				if (select(s + 1, &rfd, NULL, NULL, NULL) == -1)
					continue;

				memset(buf, 0, TFTP_BUF);
				clilen = sizeof cli;
				len = recvfrom(s, buf, TFTP_BUF, 0, (struct sockaddr*) &cli, 
						(socklen_t*) &clilen);
				if (len == -1) {
					VERB(5) printf("Error:: in recvfrom #%d - %s\n", 
							errno, strerror(errno));
					continue;
				}

				tftp = (struct tftphdr*) (pos = buf);
				VERB(5) printf("Info(5):: Received packet from %s len %d with opcode=%hd\n", 
						inet_ntoa(cli.sin_addr), len, ntohs(tftp->th_opcode));
				switch (ntohs(tftp->th_opcode)) {
					case WRQ:
						len -= 2;
						pos += 2;
						strlcpy(szFName, (char*) pos, MAX_STR);
						VERB(5) printf("Info(5):: Get filename %s\n", szFName);
						len -= strlen((char*) pos) + 1;
						pos += strlen((char*) pos) + 1;
						VERB(5) printf("Info(5):: Get mode %s len=%d\n", pos, len);
						if (strncmp((char*) pos, "octet", len)) {
							memset(buf, 0, TFTP_BUF);
							tftp->th_opcode = htons(ERROR);
							tftp->th_code = htons(EBADOP);
							strncpy(tftp->th_data, "Error:: mode not supported", 27);
							sendto(s, buf, 31, 0, (struct sockaddr*) &cli, sizeof cli);
							continue;
						}
						VERB(2) printf("Info(2):: Receive file %s from %s\n", 
								szFName, inet_ntoa(cli.sin_addr));

						f = open(szFName, O_WRONLY | O_CREAT | O_EXCL, 0644);
						if (f == -1) {
							memset(buf, 0, TFTP_BUF);
							tftp->th_opcode = htons(ERROR);
							switch (errno) {
								case EACCES:
								case EPERM:
									tftp->th_code = htons(EACCESS);
									break;
								case EEXIST:
									tftp->th_code = htons(EEXISTS);
									break;
								default:
									tftp->th_code = htons(ENOSPACE);
							}
							snprintf(tftp->th_data, STRSIZ, "Error:: in file %s", 
									strerror(errno));
							sendto(s, buf, strlen(tftp->th_data) + 4, 0, 
									(struct sockaddr*) &cli, sizeof cli);
							continue;
						}

						memset(buf, 0, TFTP_BUF);
						tftp->th_opcode = htons(ACK);
						tftp->th_block = seq = 0;
						sendto(s, tftp, 4, 0, (struct sockaddr*) &cli, sizeof cli);

						for (retry = TFTP_RETRY; retry;) {
							FD_ZERO(&rfd);
							FD_SET(s, &rfd);
							if (select(s + 1, &rfd, NULL, NULL, &tv) < 1) {
								retry--;
								continue;
							}
							memset(buf, 0, TFTP_BUF);
							clilen = sizeof sin;
							if ((len = recvfrom(s, buf, TFTP_BUF, 0, 
										(struct sockaddr*) &rcv, 
										(socklen_t*) &clilen)) == -1) {
								VERB(5) printf("Error:: in recvfrom #%d - %s\n", 
										errno, strerror(errno));
								retry--;
								continue;
							} else
								if (cli.sin_addr.s_addr != rcv.sin_addr.s_addr)
									continue;

							VERB(5) printf("Info(5):: received opcode=%d block=%d seq=%d\n", 
									ntohs(tftp->th_opcode), ntohs(tftp->th_block), seq);
							if (ERROR == ntohs(tftp->th_opcode)) {
								syslog(LOG_ERR, "Error:: in tftp receiving #%d - %s", 
										tftp->th_code, tftp->th_data);
								close(f);
								unlink(szFName);
								break;
							}
							if (DATA == ntohs(tftp->th_opcode) && 
									++seq == ntohs(tftp->th_block)) {
								if (write(f, tftp->th_data, len - 4) == -1) {
									syslog(LOG_ERR, "Error:: Can`t write to file %s\n", 
											szFName);
									close(f);
									unlink(szFName);
									break;
								}

								memset(buf, 0, TFTP_BUF);
								tftp->th_opcode = htons(ACK);
								tftp->th_block = htons(seq);
								sendto(s, tftp, 4, 0, (struct sockaddr*) &rcv, sizeof rcv);
								VERB(5) printf("Info(5):: Send ACK for %s block=%d\n", 
										inet_ntoa(cli.sin_addr), seq);

								if (SEGSIZE > len - 4) {
									close(f);
									syslog(LOG_INFO, "TFTP transfer complete to %s", 
											szFName);
									break;
								}
							} else {
								memset(buf, 0, TFTP_BUF);
								tftp->th_opcode = htons(ERROR);
								tftp->th_code = htons(EBADID);
								snprintf(tftp->th_data, STRSIZ, "Error:: in transfer #%d", 
										seq);
								sendto(s, buf, strlen(tftp->th_data) + 4, 0, 
										(struct sockaddr*) &cli, sizeof cli);
								retry--;
							}
						}
						if (!retry) {
							close(f);
							unlink(szFName);
							syslog(LOG_ERR, "Error:: transfer aborted - timeout!");
						}

						break;
					case RRQ:
						len -= 2;
						pos += 2;
						strlcpy(szFName, (char*) pos, MAX_STR);
						VERB(5) printf("Info(5):: Get filename %s\n", szFName);
						len -= strlen((char*) pos) + 1;
						pos += strlen((char*) pos) + 1;
						VERB(5) printf("Info(5):: Get mode %s len=%d\n", pos, len);
						if (strncmp((char*) pos, "octet", len)) {
							memset(buf, 0, TFTP_BUF);
							tftp->th_opcode = htons(ERROR);
							tftp->th_code = htons(EBADOP);
							strncpy(tftp->th_data, "Error:: mode not supported", 27);
							sendto(s, buf, 31, 0, (struct sockaddr*) &cli, sizeof cli);
							continue;
						}
						VERB(2) printf("Info(2):: Send file %s to %s\n", 
								szFName, inet_ntoa(cli.sin_addr));

						f = open(szFName, O_RDONLY);
						if (f == -1) {
							memset(buf, 0, TFTP_BUF);
							tftp->th_opcode = htons(ERROR);
							switch (errno) {
								case EACCES:
								case EPERM:
									tftp->th_code = htons(EACCESS);
									break;
								case ENOENT:
									tftp->th_code = htons(ENOTFOUND);
									break;
								default:
									tftp->th_code = htons(ENOSPACE);
							}
							snprintf(tftp->th_data, STRSIZ, "Error:: in file %s", 
									strerror(errno));
							sendto(s, buf, strlen(tftp->th_data) + 4, 0, 
									(struct sockaddr*) &cli, sizeof cli);
							continue;
						} else
							seq = 1;

						for (retry = TFTP_RETRY; retry;) {
							tftp->th_opcode = htons(DATA);
							tftp->th_block = htons(seq);
							if ((len = read(f, tftp->th_data, SEGSIZE)) == -1) {
								syslog(LOG_ERR, "Error:: Can`t read from file %s\n", 
										szFName);
								close(f);
								break;
							} else
								sendto(s, buf, len + 4, 0, 
										(struct sockaddr*) &cli, sizeof cli);

							FD_ZERO(&rfd);
							FD_SET(s, &rfd);
							if (select(s + 1, &rfd, NULL, NULL, &tv) < 1) {
								retry--;
								continue;
							}
							memset(buf, 0, TFTP_BUF);
							clilen = sizeof sin;
							if (recvfrom(s, buf, TFTP_BUF, 0, (struct sockaddr*) &rcv, 
										(socklen_t*) &clilen) == -1) {
								VERB(5) printf("Error:: in recvfrom #%d - %s\n", 
										errno, strerror(errno));
								retry--;
								continue;
							} else
								if (cli.sin_addr.s_addr != rcv.sin_addr.s_addr)
									continue;

							VERB(5) printf("Info(5):: received opcode=%d block=%d seq=%d\n", 
									ntohs(tftp->th_opcode), ntohs(tftp->th_block), seq);
							if (ERROR == ntohs(tftp->th_opcode)) {
								syslog(LOG_ERR, "Error:: in tftp sending #%d - %s", 
										tftp->th_code, tftp->th_data);
								if (lseek(f, len * -1, SEEK_CUR) == -1) {
									syslog(LOG_ERR, "Error:: revert sending #%d - %s", 
											errno, strerror(errno));
									close(f);
									break;
								}
								retry--;
								continue;
							}
							if (ACK == ntohs(tftp->th_opcode) && 
									seq == ntohs(tftp->th_block)) {
								seq++;
								if (SEGSIZE > len) {
									close(f);
									syslog(LOG_INFO, "TFTP transfer complete to %s", 
											szFName);
									break;
								}
							} else {
								memset(buf, 0, TFTP_BUF);
								tftp->th_opcode = htons(ERROR);
								tftp->th_code = htons(EBADID);
								snprintf(tftp->th_data, STRSIZ, "Error:: in transfer #%d", 
										seq);
								sendto(s, buf, strlen(tftp->th_data) + 4, 0, 
										(struct sockaddr*) &cli, sizeof cli);
								retry--;
							}
						}
						if (!retry) {
							close(f);
							syslog(LOG_ERR, "Error:: transfer aborted - timeout!");
						}

						break;
					case DATA:
						if (seq == 0xffff)
							VERB(5) printf("Error:: not specified operation!\n");
						break;
				}
			}

			break;
	}


	close(s);
	return 0;
}