release

author: SkywalkerSW5 <skywalkersw5@yahoo.com> 2021-12-18 20:07:34 +0000
committer: SkywalkerSW5 <skywalkersw5@yahoo.com> 2021-12-18 20:07:34 +0000
commit: d411b6e3cb33043de0943f6066bea77a7a962823 (patch)
tree: d5a2fe8df8046bcf9cd3ac8b2429f628c13c78ee /ittpd.c
1 files changed, 195 insertions, 0 deletions
diff --git a/ittpd.c b/ittpd.c
new file mode 100644
index 0000000..d4bfa37
--- /dev/null
+++ b/ittpd.c
@@ -0,0 +1,195 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#define VERSION 23
+#define BUFSIZE 8096
+#define ERROR      42
+#define LOG        44
+#define FORBIDDEN 403
+#define NOTFOUND  404
+
+struct {
+	char *ext;
+	char *filetype;
+} extensions [] = {
+	{"gif", "image/gif" },  
+	{"jpg", "image/jpg" }, 
+	{"jpeg","image/jpeg"},
+	{"png", "image/png" },  
+	{"ico", "image/ico" },  
+	{"zip", "image/zip" },  
+	{"gz",  "image/gz"  },  
+	{"tar", "image/tar" },  
+	{"htm", "text/html" },  
+	{"html","text/html" },  
+    {"css", "text/css"  },
+    {"js",  "text/js"   },
+	{"json","application/json" },  
+	{0,0} };
+
+void logger(int type, char *s1, char *s2, int socket_fd)
+{
+	int fd ;
+	char logbuffer[BUFSIZE*2];
+
+	switch (type) {
+	case ERROR: (void)sprintf(logbuffer,"ERROR: %s:%s Errno=%d exiting pid=%d",s1, s2, errno,getpid()); 
+		break;
+	case FORBIDDEN: 
+		(void)write(socket_fd, "HTTP/1.1 403 Forbidden\nContent-Length: 185\nConnection: close\nContent-Type: text/html\n\n<html><head>\n<title>403 Forbidden</title>\n</head><body>\n<h1>Forbidden</h1>\nThe requested URL, file type or operation is not allowed on this simple static file webserver.\n</body></html>\n",271);
+		(void)sprintf(logbuffer,"FORBIDDEN: %s:%s",s1, s2); 
+		break;
+	case NOTFOUND: 
+		(void)write(socket_fd, "HTTP/1.1 404 Not Found\nContent-Length: 136\nConnection: close\nContent-Type: text/html\n\n<html><head>\n<title>404 Not Found</title>\n</head><body>\n<h1>Not Found</h1>\nThe requested URL was not found on this server.\n</body></html>\n",224);
+		(void)sprintf(logbuffer,"NOT FOUND: %s:%s",s1, s2); 
+		break;
+	case LOG: (void)sprintf(logbuffer," INFO: %s:%s:%d",s1, s2,socket_fd); break;
+	}	
+	/* No checks here, nothing can be done with a failure anyway */
+	if((fd = open("ittpd.log", O_CREAT| O_WRONLY | O_APPEND,0644)) >= 0) {
+		(void)write(fd,logbuffer,strlen(logbuffer)); 
+		(void)write(fd,"\n",1);      
+		(void)close(fd);
+	}
+	if(type == ERROR || type == NOTFOUND || type == FORBIDDEN) exit(3);
+}
+
+/* this is a child web server process, so we can exit on errors */
+void web(int fd, int hit)
+{
+	int j, file_fd, buflen;
+	long i, ret, len;
+	char * fstr;
+	static char buffer[BUFSIZE+1]; /* static so zero filled */
+
+	ret =read(fd,buffer,BUFSIZE); 	/* read Web request in one go */
+	if(ret == 0 || ret == -1) {	/* read failure stop now */
+		logger(FORBIDDEN,"failed to read browser request","",fd);
+	}
+	if(ret > 0 && ret < BUFSIZE)	/* return code is valid chars */
+		buffer[ret]=0;		/* terminate the buffer */
+	else buffer[0]=0;
+	for(i=0;i<ret;i++)	/* remove CF and LF characters */
+		if(buffer[i] == '\r' || buffer[i] == '\n')
+			buffer[i]='*';
+	logger(LOG,"request",buffer,hit);
+	if( strncmp(buffer,"GET ",4) && strncmp(buffer,"get ",4) ) {
+		logger(FORBIDDEN,"Only simple GET operation supported",buffer,fd);
+	}
+	for(i=4;i<BUFSIZE;i++) { /* null terminate after the second space to ignore extra stuff */
+		if(buffer[i] == ' ') { /* string is "GET URL " +lots of other stuff */
+			buffer[i] = 0;
+			break;
+		}
+	}
+	for(j=0;j<i-1;j++) 	/* check for illegal parent directory use .. */
+		if(buffer[j] == '.' && buffer[j+1] == '.') {
+			logger(FORBIDDEN,"Parent directory (..) path names not supported",buffer,fd);
+		}
+	if( !strncmp(&buffer[0],"GET /\0",6) || !strncmp(&buffer[0],"get /\0",6) ) /* convert no filename to index file */
+		(void)strcpy(buffer,"GET /index.html");
+
+	/* work out the file type and check we support it */
+	buflen=strlen(buffer);
+	fstr = (char *)0;
+	for(i=0;extensions[i].ext != 0;i++) {
+		len = strlen(extensions[i].ext);
+		if( !strncmp(&buffer[buflen-len], extensions[i].ext, len)) {
+			fstr =extensions[i].filetype;
+			break;
+		}
+	}
+	if(fstr == 0) logger(FORBIDDEN,"file extension type not supported",buffer,fd);
+
+	if(( file_fd = open(&buffer[5],O_RDONLY)) == -1) {  /* open the file for reading */
+		logger(NOTFOUND, "failed to open file",&buffer[5],fd);
+	}
+	logger(LOG,"SEND",&buffer[5],hit);
+	len = (long)lseek(file_fd, (off_t)0, SEEK_END); /* lseek to the file end to find the length */
+	      (void)lseek(file_fd, (off_t)0, SEEK_SET); /* lseek back to the file start ready for reading */
+          (void)sprintf(buffer,"HTTP/1.1 200 OK\nServer: ittpd/%d.0\nContent-Length: %ld\nConnection: close\nContent-Type: %s\n\n", VERSION, len, fstr); /* Header + a blank line */
+	logger(LOG,"Header",buffer,hit);
+	(void)write(fd,buffer,strlen(buffer));
+
+	/* send file in 8KB block - last block may be smaller */
+	while (	(ret = read(file_fd, buffer, BUFSIZE)) > 0 ) {
+		(void)write(fd,buffer,ret);
+	}
+	sleep(1);	/* allow socket to drain before signalling the socket is closed */
+	close(fd);
+	exit(1);
+}
+
+int main(int argc, char **argv)
+{
+	int i, port, pid, listenfd, socketfd, hit;
+	socklen_t length;
+	static struct sockaddr_in cli_addr; /* static = initialised to zeros */
+	static struct sockaddr_in serv_addr; /* static = initialised to zeros */
+
+	if( argc < 3  || argc > 3 || !strcmp(argv[1], "-?") ) {
+		(void)printf("hint: ittpd Port-Number Top-Directory\t\tversion %d\n\n"
+        "ittpd is a very small web server\n"
+        "\n"
+        "example: ittpd 8181 /server/website\n"      
+ );
+		exit(0);
+	}
+	if( !strncmp(argv[2],"/"   ,2 ) || !strncmp(argv[2],"/etc", 5 ) ||
+	    !strncmp(argv[2],"/bin",5 ) || !strncmp(argv[2],"/lib", 5 ) ||
+	    !strncmp(argv[2],"/tmp",5 ) || !strncmp(argv[2],"/usr", 5 ) ||
+	    !strncmp(argv[2],"/dev",5 ) || !strncmp(argv[2],"/sbin",6) ){
+		(void)printf("ERROR: Bad top directory %s, see ittpd -?\n",argv[2]);
+		exit(3);
+	}
+	if(chdir(argv[2]) == -1){ 
+		(void)printf("ERROR: Can't Change to directory %s\n",argv[2]);
+		exit(4);
+	}
+	/* Become deamon + unstopable and no zombies children (= no wait()) */
+	if(fork() != 0)
+		return 0; /* parent returns OK to shell */
+	(void)signal(SIGCHLD, SIG_IGN); /* ignore child death */
+	(void)signal(SIGHUP, SIG_IGN); /* ignore terminal hangups */
+	for(i=0;i<32;i++)
+		(void)close(i);		/* close open files */
+	(void)setpgrp();		/* break away from process group */
+	logger(LOG,"ittpd starting",argv[1],getpid());
+	/* setup the network socket */
+	if((listenfd = socket(AF_INET, SOCK_STREAM,0)) <0)
+		logger(ERROR, "system call","socket",0);
+	port = atoi(argv[1]);
+	if(port < 0 || port >60000)
+		logger(ERROR,"Invalid port number (try 1->60000)",argv[1],0);
+	serv_addr.sin_family = AF_INET;
+	serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
+	serv_addr.sin_port = htons(port);
+	if(bind(listenfd, (struct sockaddr *)&serv_addr,sizeof(serv_addr)) <0)
+		logger(ERROR,"system call","bind",0);
+	if( listen(listenfd,64) <0)
+		logger(ERROR,"system call","listen",0);
+	for(hit=1; ;hit++) {
+		length = sizeof(cli_addr);
+		if((socketfd = accept(listenfd, (struct sockaddr *)&cli_addr, &length)) < 0)
+			logger(ERROR,"system call","accept",0);
+		if((pid = fork()) < 0) {
+			logger(ERROR,"system call","fork",0);
+		}
+		else {
+			if(pid == 0) { 	/* child */
+				(void)close(listenfd);
+				web(socketfd,hit); /* never returns */
+			} else { 	/* parent */
+				(void)close(socketfd);
+			}
+		}
+	}
+}
+\ No newline at end of file
author	SkywalkerSW5 <skywalkersw5@yahoo.com>	2021-12-18 20:07:34 +0000
committer	SkywalkerSW5 <skywalkersw5@yahoo.com>	2021-12-18 20:07:34 +0000
commit	d411b6e3cb33043de0943f6066bea77a7a962823 (patch)
tree	d5a2fe8df8046bcf9cd3ac8b2429f628c13c78ee /ittpd.c