2 A trivial static http webserver using Libevent's evhttp.
4 This is not the best code in the world, and it does some fairly stupid stuff
5 that you would never want to do in a production webserver. Caveat hackor!
9 /* Compatibility for possible missing IPv6 declarations */
10 #include "../util-internal.h"
16 #include <sys/types.h>
26 #define S_ISDIR(x) (((x) & S_IFMT) == S_IFDIR)
30 #include <sys/socket.h>
37 #include <event2/event.h>
38 #include <event2/http.h>
39 #include <event2/buffer.h>
40 #include <event2/util.h>
41 #include <event2/keyvalq_struct.h>
43 #ifdef EVENT__HAVE_NETINET_IN_H
44 #include <netinet/in.h>
45 # ifdef _XOPEN_SOURCE_EXTENDED
46 # include <arpa/inet.h>
64 #define O_RDONLY _O_RDONLY
70 static const struct table_entry {
71 const char *extension;
72 const char *content_type;
73 } content_type_table[] = {
74 { "txt", "text/plain" },
75 { "c", "text/plain" },
76 { "h", "text/plain" },
77 { "html", "text/html" },
78 { "htm", "text/htm" },
79 { "css", "text/css" },
80 { "gif", "image/gif" },
81 { "jpg", "image/jpeg" },
82 { "jpeg", "image/jpeg" },
83 { "png", "image/png" },
84 { "pdf", "application/pdf" },
85 { "ps", "application/postscript" },
89 /* Try to guess a good content-type for 'path' */
91 guess_content_type(const char *path)
93 const char *last_period, *extension;
94 const struct table_entry *ent;
95 last_period = strrchr(path, '.');
96 if (!last_period || strchr(last_period, '/'))
97 goto not_found; /* no exension */
98 extension = last_period + 1;
99 for (ent = &content_type_table[0]; ent->extension; ++ent) {
100 if (!evutil_ascii_strcasecmp(ent->extension, extension))
101 return ent->content_type;
105 return "application/misc";
108 /* Callback used for the /dump URI, and for every non-GET request:
109 * dumps all information to stdout and gives back a trivial 200 ok */
111 dump_request_cb(struct evhttp_request *req, void *arg)
114 struct evkeyvalq *headers;
115 struct evkeyval *header;
116 struct evbuffer *buf;
118 switch (evhttp_request_get_command(req)) {
119 case EVHTTP_REQ_GET: cmdtype = "GET"; break;
120 case EVHTTP_REQ_POST: cmdtype = "POST"; break;
121 case EVHTTP_REQ_HEAD: cmdtype = "HEAD"; break;
122 case EVHTTP_REQ_PUT: cmdtype = "PUT"; break;
123 case EVHTTP_REQ_DELETE: cmdtype = "DELETE"; break;
124 case EVHTTP_REQ_OPTIONS: cmdtype = "OPTIONS"; break;
125 case EVHTTP_REQ_TRACE: cmdtype = "TRACE"; break;
126 case EVHTTP_REQ_CONNECT: cmdtype = "CONNECT"; break;
127 case EVHTTP_REQ_PATCH: cmdtype = "PATCH"; break;
128 default: cmdtype = "unknown"; break;
131 printf("Received a %s request for %s\nHeaders:\n",
132 cmdtype, evhttp_request_get_uri(req));
134 headers = evhttp_request_get_input_headers(req);
135 for (header = headers->tqh_first; header;
136 header = header->next.tqe_next) {
137 printf(" %s: %s\n", header->key, header->value);
140 buf = evhttp_request_get_input_buffer(req);
141 puts("Input data: <<<");
142 while (evbuffer_get_length(buf)) {
145 n = evbuffer_remove(buf, cbuf, sizeof(cbuf));
147 (void) fwrite(cbuf, 1, n, stdout);
151 evhttp_send_reply(req, 200, "OK", NULL);
154 /* This callback gets invoked when we get any http request that doesn't match
155 * any other callback. Like any evhttp server callback, it has a simple job:
156 * it must eventually call evhttp_send_error() or evhttp_send_reply().
159 send_document_cb(struct evhttp_request *req, void *arg)
161 struct evbuffer *evb = NULL;
162 const char *docroot = arg;
163 const char *uri = evhttp_request_get_uri(req);
164 struct evhttp_uri *decoded = NULL;
167 char *whole_path = NULL;
172 if (evhttp_request_get_command(req) != EVHTTP_REQ_GET) {
173 dump_request_cb(req, arg);
177 printf("Got a GET request for <%s>\n", uri);
180 decoded = evhttp_uri_parse(uri);
182 printf("It's not a good URI. Sending BADREQUEST\n");
183 evhttp_send_error(req, HTTP_BADREQUEST, 0);
187 /* Let's see what path the user asked for. */
188 path = evhttp_uri_get_path(decoded);
189 if (!path) path = "/";
191 /* We need to decode it, to see what path the user really wanted. */
192 decoded_path = evhttp_uridecode(path, 0, NULL);
193 if (decoded_path == NULL)
195 /* Don't allow any ".."s in the path, to avoid exposing stuff outside
196 * of the docroot. This test is both overzealous and underzealous:
197 * it forbids aceptable paths like "/this/one..here", but it doesn't
198 * do anything to prevent symlink following." */
199 if (strstr(decoded_path, ".."))
202 len = strlen(decoded_path)+strlen(docroot)+2;
203 if (!(whole_path = malloc(len))) {
207 evutil_snprintf(whole_path, len, "%s/%s", docroot, decoded_path);
209 if (stat(whole_path, &st)<0) {
213 /* This holds the content we're sending. */
214 evb = evbuffer_new();
216 if (S_ISDIR(st.st_mode)) {
217 /* If it's a directory, read the comments and make a little
221 WIN32_FIND_DATAA ent;
228 const char *trailing_slash = "";
230 if (!strlen(path) || path[strlen(path)-1] != '/')
231 trailing_slash = "/";
234 dirlen = strlen(whole_path);
235 pattern = malloc(dirlen+3);
236 memcpy(pattern, whole_path, dirlen);
237 pattern[dirlen] = '\\';
238 pattern[dirlen+1] = '*';
239 pattern[dirlen+2] = '\0';
240 d = FindFirstFileA(pattern, &ent);
242 if (d == INVALID_HANDLE_VALUE)
245 if (!(d = opendir(whole_path)))
249 evbuffer_add_printf(evb,
252 " <meta charset='utf-8'>\n"
253 " <title>%s</title>\n"
254 " <base href='%s%s'>\n"
259 decoded_path, /* XXX html-escape this. */
260 path, /* XXX html-escape this? */
262 decoded_path /* XXX html-escape this */);
265 const char *name = ent.cFileName;
267 while ((ent = readdir(d))) {
268 const char *name = ent->d_name;
270 evbuffer_add_printf(evb,
271 " <li><a href=\"%s\">%s</a>\n",
272 name, name);/* XXX escape this */
274 } while (FindNextFileA(d, &ent));
278 evbuffer_add_printf(evb, "</ul></body></html>\n");
284 evhttp_add_header(evhttp_request_get_output_headers(req),
285 "Content-Type", "text/html");
287 /* Otherwise it's a file; add it to the buffer to get
288 * sent via sendfile */
289 const char *type = guess_content_type(decoded_path);
290 if ((fd = open(whole_path, O_RDONLY)) < 0) {
295 if (fstat(fd, &st)<0) {
296 /* Make sure the length still matches, now that we
297 * opened the file :/ */
301 evhttp_add_header(evhttp_request_get_output_headers(req),
302 "Content-Type", type);
303 evbuffer_add_file(evb, fd, 0, st.st_size);
306 evhttp_send_reply(req, 200, "OK", evb);
309 evhttp_send_error(req, 404, "Document was not found");
314 evhttp_uri_free(decoded);
326 fprintf(stdout, "Syntax: http-server <docroot>\n");
330 main(int argc, char **argv)
332 struct event_base *base;
334 struct evhttp_bound_socket *handle;
336 ev_uint16_t port = 0;
339 WSAStartup(0x101, &WSAData);
341 if (signal(SIGPIPE, SIG_IGN) == SIG_ERR)
349 base = event_base_new();
351 fprintf(stderr, "Couldn't create an event_base: exiting\n");
355 /* Create a new evhttp object to handle requests. */
356 http = evhttp_new(base);
358 fprintf(stderr, "couldn't create evhttp. Exiting.\n");
362 /* The /dump URI will dump all requests to stdout and say 200 ok. */
363 evhttp_set_cb(http, "/dump", dump_request_cb, NULL);
365 /* We want to accept arbitrary requests, so we need to set a "generic"
366 * cb. We can also add callbacks for specific paths. */
367 evhttp_set_gencb(http, send_document_cb, argv[1]);
369 /* Now we tell the evhttp what port to listen on */
370 handle = evhttp_bind_socket_with_handle(http, "0.0.0.0", port);
372 fprintf(stderr, "couldn't bind to port %d. Exiting.\n",
378 /* Extract and display the address we're listening on. */
379 struct sockaddr_storage ss;
381 ev_socklen_t socklen = sizeof(ss);
386 fd = evhttp_bound_socket_get_fd(handle);
387 memset(&ss, 0, sizeof(ss));
388 if (getsockname(fd, (struct sockaddr *)&ss, &socklen)) {
389 perror("getsockname() failed");
392 if (ss.ss_family == AF_INET) {
393 got_port = ntohs(((struct sockaddr_in*)&ss)->sin_port);
394 inaddr = &((struct sockaddr_in*)&ss)->sin_addr;
395 } else if (ss.ss_family == AF_INET6) {
396 got_port = ntohs(((struct sockaddr_in6*)&ss)->sin6_port);
397 inaddr = &((struct sockaddr_in6*)&ss)->sin6_addr;
399 fprintf(stderr, "Weird address family %d\n",
403 addr = evutil_inet_ntop(ss.ss_family, inaddr, addrbuf,
406 printf("Listening on %s:%d\n", addr, got_port);
407 evutil_snprintf(uri_root, sizeof(uri_root),
408 "http://%s:%d",addr,got_port);
410 fprintf(stderr, "evutil_inet_ntop failed\n");
415 event_base_dispatch(base);