simple_httpd.c revision 94135 
1/*-
2 * Simple_HTTPd v1.1 - a very small, barebones HTTP server
3 *
4 * Copyright (c) 1998-1999 Marc Nicholas <marc@netstor.com>
5 * All rights reserved.
6 *
7 * Major rewrite by William Lloyd <wlloyd@slap.net>
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD: head/release/picobsd/tinyware/simple_httpd/simple_httpd.c 94135 2002-04-07 17:42:27Z asmodai $
31 */
32
33#include <sys/stat.h>
34#include <sys/time.h>
35#include <sys/types.h>
36#include <sys/socket.h>
37#include <sys/wait.h>
38#include <netinet/in.h>
39#include <arpa/inet.h>
40
41#include <fcntl.h>
42#include <netdb.h>
43#include <signal.h>
44#include <stdio.h>
45#include <stdlib.h>
46#include <string.h>
47#include <time.h>
48#include <unistd.h>
49
50int             http_port = 80;
51int             daemonize = 1;
52int             verbose = 0;
53int             http_sock, con_sock;
54
55char            fetch_mode[100];
56char            homedir[100];
57char            logfile[80];
58char           *adate();
59
60struct hostent *hst;
61struct sockaddr_in source;
62
63/* HTTP basics */
64static char httpd_server_ident[] = "Server: FreeBSD/PicoBSD simple_httpd 1.1\r";
65
66static char http_200[] = "HTTP/1.0 200 OK\r";
67
68/* Two parts, HTTP Header and then HTML */
69static char *http_404[2] =
70    {"HTTP/1.0 404 Not found\r\n",
71"<HTML><HEAD><TITLE>Error</TITLE></HEAD><BODY><H1>Error 404</H1>\
72Not found - file doesn't exist or you do not have permission.\n</BODY></HTML>\r\n"
73};
74
75static char *http_405[2] =
76    {"HTTP/1.0 405 Method Not allowed\r\nAllow: GET,HEAD\r\n",
77"<HTML><HEAD><TITLE>Error</TITLE></HEAD><BODY><H1>Error 405</H1>\
78This server only supports GET and HEAD requests.\n</BODY></HTML>\r\n"
79};
80
81/*
82 * Only called on initial invocation
83 */
84void
85init_servconnection(void)
86{
87	struct sockaddr_in server;
88
89	/* Create a socket */
90	http_sock = socket(AF_INET, SOCK_STREAM, 0);
91	if (http_sock < 0) {
92		perror("socket");
93		exit(1);
94	}
95	server.sin_family = AF_INET;
96	server.sin_port = htons(http_port);
97	server.sin_addr.s_addr = INADDR_ANY;
98	if (bind(http_sock, (struct sockaddr *) & server, sizeof(server)) < 0) {
99		perror("bind socket");
100		exit(1);
101	}
102        if (verbose) printf("simple_httpd:%d\n",http_port);
103}
104
105/*
106 * Wait here until we see an incoming http request
107 */
108void
109wait_connection(void)
110{
111	int lg;
112
113	lg = sizeof(struct sockaddr_in);
114
115	con_sock = accept(http_sock, (struct sockaddr *) & source, &lg);
116	if (con_sock <= 0) {
117		perror("accept");
118		exit(1);
119	}
120}
121
122/*
123 * Print timestamp for HTTP HEAD and GET
124 */
125void
126http_date(void)
127{
128	time_t	tl;
129	char	buff[50];
130
131	tl = time(NULL);
132	strftime(buff, 50, "Date: %a, %d %h %Y %H:%M:%S %Z\r\n", gmtime(&tl));
133	write(con_sock, buff, strlen(buff));
134	//return(buff);
135}
136
137/*
138 * Send data to the open socket
139 */
140void
141http_output(char *html)
142{
143        write(con_sock, html, strlen(html));
144        write(con_sock, "\r\n", 2);
145}
146
147
148/*
149 * Create and write the log information to file
150 * Log file format is one line per entry
151 */
152void
153log_line(char *req)
154{
155        char            log_buff[256];
156        char            msg[1024];
157	char            env_host[80], env_addr[80];
158	long            addr;
159	FILE           *log;
160
161	strcpy(log_buff,inet_ntoa(source.sin_addr));
162	sprintf(env_addr, "REMOTE_ADDR=%s",log_buff);
163
164        addr=inet_addr(log_buff);
165
166        strcpy(msg,adate());
167        strcat(msg,"    ");
168        hst=gethostbyaddr((char*) &addr, 4, AF_INET);
169
170	/* If DNS hostname exists */
171        if (hst) {
172	  strcat(msg,hst->h_name);
173	  sprintf(env_host, "REMOTE_HOST=%s",hst->h_name);
174	}
175        strcat(msg," (");
176        strcat(msg,log_buff);
177        strcat(msg,")   ");
178        strcat(msg,req);
179
180	if (daemonize) {
181	  log=fopen(logfile,"a");
182	  fprintf(log,"%s\n",msg);
183	  fclose(log);
184	} else
185	  printf("%s\n",msg);
186
187	/* This is for CGI scripts */
188	putenv(env_addr);
189	putenv(env_host);
190}
191
192/*
193 * We have a connection.  Identify what type of request GET, HEAD, CGI, etc
194 * and do what needs to be done
195 */
196void
197http_request(void)
198{
199	int             fd, lg, i;
200	int             cmd = 0;
201	char           *p, *par;
202	char           *filename, *c;
203	struct stat     file_status;
204	char            req[1024];
205	char            buff[8192];
206
207	lg = read(con_sock, req, 1024);
208
209        if (p=strstr(req,"\n")) *p=0;
210        if (p=strstr(req,"\r")) *p=0;
211
212	log_line(req);
213
214	c = strtok(req, " ");
215
216	/* Error msg if request is nothing */
217	if (c == NULL) {
218	  http_output(http_404[0]);
219	  http_output(http_404[1]);
220	  goto end_request;
221	}
222
223	if (strncmp(c, "GET", 3) == 0) cmd = 1;
224	if (strncmp(c, "HEAD", 4) == 0) cmd = 2;
225
226	/* Do error msg for any other type of request */
227	if (cmd == 0) {
228	  http_output(http_405[0]);
229	  http_output(http_405[1]);
230	  goto end_request;
231	}
232
233	filename = strtok(NULL, " ");
234
235	c = strtok(NULL, " ");
236	if (fetch_mode[0] != NULL) strcpy(filename,fetch_mode);
237	if (filename == NULL ||
238            strlen(filename)==1) filename="/index.html";
239
240	while (filename[0]== '/') filename++;
241
242        /* CGI handling.  Untested */
243        if (!strncmp(filename,"cgi-bin/",8))
244           {
245           par=0;
246           if (par=strstr(filename,"?"))
247              {
248               *par=0;
249                par++;
250              }
251           if (access(filename,X_OK)) goto conti;
252           stat (filename,&file_status);
253           if (setuid(file_status.st_uid)) return(0);
254           if (seteuid(file_status.st_uid)) return(0);
255           if (!fork())
256              {
257               close(1);
258               dup(con_sock);
259               //printf("HTTP/1.0 200 OK\nContent-type: text/html\n\n\n");
260	       printf("HTTP/1.0 200 OK\r\n");
261               /* Plug in environment variable, others in log_line */
262	       putenv("SERVER_SOFTWARE=FreeBSD/PicoBSD");
263
264	       execlp (filename,filename,par,(char *)0);
265              }
266            wait(&i);
267            return(0);
268            }
269        conti:
270	if (filename == NULL) {
271	  http_output(http_405[0]);
272	  http_output(http_405[1]);
273	  goto end_request;
274	}
275	/* End of CGI handling */
276
277	/* Reject any request with '..' in it, bad hacker */
278	c = filename;
279	while (*c != '\0')
280	  if (c[0] == '.' && c[1] == '.') {
281	    http_output(http_404[0]);
282	    http_output(http_404[1]);
283	    goto end_request;
284	  } else
285	    c++;
286
287	/* Open filename */
288	fd = open(filename, O_RDONLY);
289	if (fd < 0) {
290	        http_output(http_404[0]);
291	        http_output(http_404[1]);
292		goto end_request;
293	}
294
295	/* Get file status information */
296	if (fstat(fd, &file_status) < 0) {
297	  http_output(http_404[0]);
298	  http_output(http_404[1]);
299	  goto end_request;
300	}
301
302	/* Is it a regular file? */
303	if (!S_ISREG(file_status.st_mode)) {
304	  http_output(http_404[0]);
305	  http_output(http_404[1]);
306	  goto end_request;
307	}
308
309	/* Past this point we are serving either a GET or HEAD */
310	/* Print all the header info */
311	http_output(http_200);
312	http_output(httpd_server_ident);
313	http_date();
314
315	sprintf(buff, "Content-length: %lld\r\n", file_status.st_size);
316
317	if (strstr(filename,".txt")) {
318	  strcpy(buff,"Content-type: text/plain\r\n");
319	} else if (strstr(filename,".html") || strstr(filename,".htm")) {
320	    strcpy(buff,"Content-type: text/html\r\n");
321	} else if (strstr(filename,".gif")) {
322	  strcpy(buff,"Content-type: image/gif\r\n");
323	} else if (strstr(filename,".jpg")) {
324	  strcpy(buff,"Content-type: image/jpeg\r\n");
325	} else {
326	  /* Take a guess at content if we don't have something already */
327	  strcpy(buff,"Content-type: ");
328	  strcat(buff,strstr(filename,".")+1);
329	  strcat(buff,"\r\n");
330	}
331	write(con_sock, buff, strlen(buff));
332
333	strftime(buff, 50, "Last-Modified: %a, %d %h %Y %H:%M:%S %Z\r\n\r\n", gmtime(&file_status.st_mtime));
334	write(con_sock, buff, strlen(buff));
335
336	/* Send data only if GET request */
337	if (cmd == 1) {
338	  while (lg = read(fd, buff, 8192))
339	    write(con_sock, buff, lg);
340	}
341
342end_request:
343	close(fd);
344	close(con_sock);
345
346}
347
348/*
349 * Simple httpd server for use in PicoBSD or other embedded application.
350 * Should satisfy simple httpd needs.  For more demanding situations
351 * apache is probably a better (but much larger) choice.
352 */
353int
354main(int argc, char *argv[])
355{
356        extern char *optarg;
357        extern int optind;
358        int ch, ld;
359	int             httpd_group = 65534;
360        pid_t server_pid;
361
362	/* Default for html directory */
363	strcpy (homedir,getenv("HOME"));
364        if (!geteuid()) strcpy (homedir,"/httphome");
365           else         strcat (homedir,"/httphome");
366
367	/* Defaults for log file */
368	if (geteuid()) {
369	    strcpy(logfile,getenv("HOME"));
370	    strcat(logfile,"/");
371	    strcat(logfile,"jhttp.log");
372	} else
373	  strcpy(logfile,"/var/log/jhttpd.log");
374
375	/* Parse command line arguments */
376	while ((ch = getopt(argc, argv, "d:f:g:l:p:vDh")) != -1)
377	  switch (ch) {
378	  case 'd':
379	    strcpy(homedir,optarg);
380	    break;
381	  case 'f':
382	    daemonize = 0;
383	    verbose = 1;
384	    strcpy(fetch_mode,optarg);
385	    break;
386	  case 'g':
387	    httpd_group = atoi(optarg);
388	    break;
389	  case 'l':
390	    strcpy(logfile,optarg);
391	    break;
392	  case 'p':
393	    http_port = atoi(optarg);
394	    break;
395	  case 'v':
396	    verbose = 1;
397	    break;
398	  case 'D':
399	    daemonize = 0;
400	    break;
401	  case '?':
402	  case 'h':
403	  default:
404	    printf("usage: simple_httpd [[-d directory][-g grpid][-l logfile][-p port][-vD]]\n");
405	    exit(1);
406	    /* NOTREACHED */
407	  }
408
409	/* Not running as root and no port supplied, assume 1080 */
410        if ((http_port == 80) && geteuid()) {
411	  http_port = 1080;
412	}
413
414	/* Do we really have rights in the html directory? */
415	if (fetch_mode[0] == NULL) {
416	  if (chdir(homedir)) {
417	    perror("chdir");
418	    puts(homedir);
419	    exit(1);
420	  }
421	}
422
423	/* Create log file if it doesn't exit */
424	if ((access(logfile,W_OK)) && daemonize) {
425	  ld = open (logfile,O_WRONLY);
426	  chmod (logfile,00600);
427	  close(ld);
428	}
429
430        init_servconnection();
431
432        if (verbose) {
433	  printf("Server started with options \n");
434	  printf("port: %d\n",http_port);
435	  if (fetch_mode[0] == NULL) printf("html home: %s\n",homedir);
436	  if (daemonize) printf("logfile: %s\n",logfile);
437	}
438
439	/* httpd is spawned */
440        if (daemonize) {
441	  if (server_pid = fork()) {
442	    wait3(0,WNOHANG,0);
443	    if (verbose) printf("pid: %d\n",server_pid);
444	    exit(0);
445	  }
446	  wait3(0,WNOHANG,0);
447	}
448
449	if (fetch_mode[0] == NULL) setpgrp(0,httpd_group);
450
451	/* How many connections do you want?
452	 * Keep this lower than the available number of processes
453	 */
454        if (listen(http_sock,15) < 0) exit(1);
455
456        label:
457	wait_connection();
458
459	if (fork()) {
460	  wait3(0,WNOHANG,0);
461	  close(con_sock);
462	  goto label;
463	}
464
465	http_request();
466
467	wait3(0,WNOHANG,0);
468	exit(0);
469}
470
471
472char *adate()
473{
474        static char out[50];
475        long now;
476        struct tm *t;
477        time(&now);
478        t = localtime(&now);
479        sprintf(out, "%02d:%02d:%02d %02d/%02d/%02d",
480                     t->tm_hour, t->tm_min, t->tm_sec,
481                     t->tm_mday, t->tm_mon+1, t->tm_year );
482        return out;
483}
484