2 * uhttpd - Tiny single-threaded httpd - CGI handler
4 * Copyright (C) 2010-2012 Jo-Philipp Wich <xm@subsignal.org>
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
20 #include "uhttpd-utils.h"
21 #include "uhttpd-cgi.h"
25 uh_cgi_header_parse(struct http_response *res, char *buf, int len, int *off)
32 if (((bufptr = strfind(buf, len, "\r\n\r\n", 4)) != NULL) ||
33 ((bufptr = strfind(buf, len, "\n\n", 2)) != NULL))
35 *off = (int)(bufptr - buf) + ((bufptr[0] == '\r') ? 4 : 2);
37 memset(res, 0, sizeof(*res));
39 res->statuscode = 200;
40 res->statusmsg = "OK";
44 for (pos = 0; pos < *off; pos++)
46 if (!hdrname && (buf[pos] == ':'))
50 if ((pos < len) && (buf[pos] == ' '))
60 else if ((buf[pos] == '\r') || (buf[pos] == '\n'))
67 if ((pos < len) && (buf[pos] == '\n'))
72 if ((hdrcount+1) < array_size(res->headers))
74 if (!strcasecmp(hdrname, "Status"))
76 res->statuscode = atoi(bufptr);
78 if (res->statuscode < 100)
79 res->statuscode = 200;
81 if (((bufptr = strchr(bufptr, ' ')) != NULL) &&
84 res->statusmsg = &bufptr[1];
87 D("CGI: HTTP/1.x %03d %s\n",
88 res->statuscode, res->statusmsg);
92 D("CGI: HTTP: %s: %s\n", hdrname, bufptr);
94 res->headers[hdrcount++] = hdrname;
95 res->headers[hdrcount++] = bufptr;
115 static char * uh_cgi_header_lookup(struct http_response *res,
120 foreach_header(i, res->headers)
122 if (!strcasecmp(res->headers[i], hdrname))
123 return res->headers[i+1];
129 static void uh_cgi_shutdown(struct uh_cgi_state *state)
134 static bool uh_cgi_socket_cb(struct client *cl)
136 int i, len, blen, hdroff;
137 char buf[UH_LIMIT_MSGHEAD];
139 struct uh_cgi_state *state = (struct uh_cgi_state *)cl->priv;
140 struct http_response *res = &cl->response;
141 struct http_request *req = &cl->request;
143 /* there is unread post data waiting */
144 while (state->content_length > 0)
146 /* remaining data in http head buffer ... */
147 if (cl->httpbuf.len > 0)
149 len = min(state->content_length, cl->httpbuf.len);
151 D("CGI: Child(%d) feed %d HTTP buffer bytes\n", cl->proc.pid, len);
153 memcpy(buf, cl->httpbuf.ptr, len);
155 cl->httpbuf.len -= len;
156 cl->httpbuf.ptr +=len;
159 /* read it from socket ... */
162 len = uh_tcp_recv(cl, buf,
163 min(state->content_length, sizeof(buf)));
165 if ((len < 0) && ((errno == EAGAIN) || (errno == EWOULDBLOCK)))
168 D("CGI: Child(%d) feed %d/%d TCP socket bytes\n",
169 cl->proc.pid, len, min(state->content_length, sizeof(buf)));
173 state->content_length -= len;
175 state->content_length = 0;
177 /* ... write to CGI process */
178 len = uh_raw_send(cl->wpipe.fd, buf, len,
179 cl->server->conf->script_timeout);
181 /* explicit EOF notification for the child */
182 if (state->content_length <= 0)
183 uh_ufd_remove(&cl->wpipe);
186 /* try to read data from child */
187 while ((len = uh_raw_recv(cl->rpipe.fd, buf, state->header_sent
188 ? sizeof(buf) : state->httpbuf.len, -1)) > 0)
190 /* we have not pushed out headers yet, parse input */
191 if (!state->header_sent)
193 /* try to parse header ... */
194 memcpy(state->httpbuf.ptr, buf, len);
195 state->httpbuf.len -= len;
196 state->httpbuf.ptr += len;
198 blen = state->httpbuf.ptr - state->httpbuf.buf;
200 if (uh_cgi_header_parse(res, state->httpbuf.buf, blen, &hdroff))
203 ensure_out(uh_http_sendf(cl, NULL,
205 "Connection: close\r\n",
206 http_versions[req->version],
207 res->statuscode, res->statusmsg));
209 /* add Content-Type if no Location or Content-Type */
210 if (!uh_cgi_header_lookup(res, "Location") &&
211 !uh_cgi_header_lookup(res, "Content-Type"))
213 ensure_out(uh_http_send(cl, NULL,
214 "Content-Type: text/plain\r\n", -1));
217 /* if request was HTTP 1.1 we'll respond chunked */
218 if ((req->version > UH_HTTP_VER_1_0) &&
219 !uh_cgi_header_lookup(res, "Transfer-Encoding"))
221 ensure_out(uh_http_send(cl, NULL,
222 "Transfer-Encoding: chunked\r\n", -1));
225 /* write headers from CGI program */
226 foreach_header(i, res->headers)
228 ensure_out(uh_http_sendf(cl, NULL, "%s: %s\r\n",
229 res->headers[i], res->headers[i+1]));
232 /* terminate header */
233 ensure_out(uh_http_send(cl, NULL, "\r\n", -1));
235 state->header_sent = true;
237 /* push out remaining head buffer */
240 D("CGI: Child(%d) relaying %d rest bytes\n",
241 cl->proc.pid, blen - hdroff);
243 ensure_out(uh_http_send(cl, req,
244 state->httpbuf.buf + hdroff,
249 /* ... failed and head buffer exceeded */
250 else if (!state->httpbuf.len)
252 /* I would do this ...
254 * uh_cgi_error_500(cl, req,
255 * "The CGI program generated an "
256 * "invalid response:\n\n");
258 * ... but in order to stay as compatible as possible,
259 * treat whatever we got as text/plain response and
260 * build the required headers here.
263 ensure_out(uh_http_sendf(cl, NULL,
265 "Content-Type: text/plain\r\n"
267 http_versions[req->version],
268 (req->version > UH_HTTP_VER_1_0)
269 ? "Transfer-Encoding: chunked\r\n" : ""
272 state->header_sent = true;
274 D("CGI: Child(%d) relaying %d invalid bytes\n",
277 ensure_out(uh_http_send(cl, req, buf, len));
282 /* headers complete, pass through buffer to socket */
283 D("CGI: Child(%d) relaying %d normal bytes\n", cl->proc.pid, len);
284 ensure_out(uh_http_send(cl, req, buf, len));
288 /* got EOF or read error from child */
290 ((errno != EAGAIN) && (errno != EWOULDBLOCK) && (len == -1)))
292 D("CGI: Child(%d) presumed dead [%s]\n", cl->proc.pid, strerror(errno));
300 if (!state->header_sent)
302 if (cl->timeout.pending)
303 uh_http_sendhf(cl, 502, "Bad Gateway",
304 "The CGI process did not produce any response\n");
306 uh_http_sendhf(cl, 504, "Gateway Timeout",
307 "The CGI process took too long to produce a "
312 uh_http_send(cl, req, "", 0);
315 uh_cgi_shutdown(state);
319 bool uh_cgi_request(struct client *cl, struct path_info *pi,
320 struct interpreter *ip)
324 int rfd[2] = { 0, 0 };
325 int wfd[2] = { 0, 0 };
329 struct uh_cgi_state *state;
330 struct http_request *req = &cl->request;
333 if (!(state = malloc(sizeof(*state))))
335 uh_http_sendhf(cl, 500, "Internal Server Error", "Out of memory");
339 /* spawn pipes for me->child, child->me */
340 if ((pipe(rfd) < 0) || (pipe(wfd) < 0))
342 if (rfd[0] > 0) close(rfd[0]);
343 if (rfd[1] > 0) close(rfd[1]);
344 if (wfd[0] > 0) close(wfd[0]);
345 if (wfd[1] > 0) close(wfd[1]);
347 uh_http_sendhf(cl, 500, "Internal Server Error",
348 "Failed to create pipe: %s\n", strerror(errno));
353 /* fork off child process */
354 switch ((child = fork()))
358 uh_http_sendhf(cl, 500, "Internal Server Error",
359 "Failed to fork child: %s\n", strerror(errno));
366 sleep(atoi(getenv("UHTTPD_SLEEP_ON_FORK") ?: "0"));
369 /* do not leak parent epoll descriptor */
372 /* close loose pipe ends */
376 /* patch stdout and stdin to pipes */
380 /* avoid leaking our pipe into child-child processes */
384 /* check for regular, world-executable file _or_ interpreter */
385 if (((pi->stat.st_mode & S_IFREG) &&
386 (pi->stat.st_mode & S_IXOTH)) || (ip != NULL))
388 /* build environment */
391 /* common information */
392 setenv("GATEWAY_INTERFACE", "CGI/1.1", 1);
393 setenv("SERVER_SOFTWARE", "uHTTPd", 1);
394 setenv("PATH", "/sbin:/usr/sbin:/bin:/usr/bin", 1);
399 setenv("HTTPS", "on", 1);
403 setenv("SERVER_NAME", sa_straddr(&cl->servaddr), 1);
404 setenv("SERVER_ADDR", sa_straddr(&cl->servaddr), 1);
405 setenv("SERVER_PORT", sa_strport(&cl->servaddr), 1);
406 setenv("REMOTE_HOST", sa_straddr(&cl->peeraddr), 1);
407 setenv("REMOTE_ADDR", sa_straddr(&cl->peeraddr), 1);
408 setenv("REMOTE_PORT", sa_strport(&cl->peeraddr), 1);
410 /* path information */
411 setenv("SCRIPT_NAME", pi->name, 1);
412 setenv("SCRIPT_FILENAME", pi->phys, 1);
413 setenv("DOCUMENT_ROOT", pi->root, 1);
414 setenv("QUERY_STRING", pi->query ? pi->query : "", 1);
417 setenv("PATH_INFO", pi->info, 1);
419 /* REDIRECT_STATUS, php-cgi wants it */
420 switch (req->redirect_status)
423 setenv("REDIRECT_STATUS", "404", 1);
427 setenv("REDIRECT_STATUS", "200", 1);
432 setenv("SERVER_PROTOCOL", http_versions[req->version], 1);
435 setenv("REQUEST_METHOD", http_methods[req->method], 1);
438 setenv("REQUEST_URI", req->url, 1);
442 setenv("REMOTE_USER", req->realm->user, 1);
444 /* request message headers */
445 foreach_header(i, req->headers)
447 if (!strcasecmp(req->headers[i], "Accept"))
448 setenv("HTTP_ACCEPT", req->headers[i+1], 1);
450 else if (!strcasecmp(req->headers[i], "Accept-Charset"))
451 setenv("HTTP_ACCEPT_CHARSET", req->headers[i+1], 1);
453 else if (!strcasecmp(req->headers[i], "Accept-Encoding"))
454 setenv("HTTP_ACCEPT_ENCODING", req->headers[i+1], 1);
456 else if (!strcasecmp(req->headers[i], "Accept-Language"))
457 setenv("HTTP_ACCEPT_LANGUAGE", req->headers[i+1], 1);
459 else if (!strcasecmp(req->headers[i], "Authorization"))
460 setenv("HTTP_AUTHORIZATION", req->headers[i+1], 1);
462 else if (!strcasecmp(req->headers[i], "Connection"))
463 setenv("HTTP_CONNECTION", req->headers[i+1], 1);
465 else if (!strcasecmp(req->headers[i], "Cookie"))
466 setenv("HTTP_COOKIE", req->headers[i+1], 1);
468 else if (!strcasecmp(req->headers[i], "Host"))
469 setenv("HTTP_HOST", req->headers[i+1], 1);
471 else if (!strcasecmp(req->headers[i], "Referer"))
472 setenv("HTTP_REFERER", req->headers[i+1], 1);
474 else if (!strcasecmp(req->headers[i], "User-Agent"))
475 setenv("HTTP_USER_AGENT", req->headers[i+1], 1);
477 else if (!strcasecmp(req->headers[i], "Content-Type"))
478 setenv("CONTENT_TYPE", req->headers[i+1], 1);
480 else if (!strcasecmp(req->headers[i], "Content-Length"))
481 setenv("CONTENT_LENGTH", req->headers[i+1], 1);
485 /* execute child code ... */
490 execl(ip->path, ip->path, pi->phys, NULL);
492 execl(pi->phys, pi->phys, NULL);
494 /* in case it fails ... */
495 printf("Status: 500 Internal Server Error\r\n\r\n"
496 "Unable to launch the requested CGI program:\n"
497 " %s: %s\n", ip ? ip->path : pi->phys, strerror(errno));
503 printf("Status: 403 Forbidden\r\n\r\n"
504 "Access to this resource is forbidden\n");
513 /* parent; handle I/O relaying */
515 memset(state, 0, sizeof(*state));
517 cl->rpipe.fd = rfd[0];
518 cl->wpipe.fd = wfd[1];
519 cl->proc.pid = child;
521 /* make pipe non-blocking */
522 fd_nonblock(cl->rpipe.fd);
523 fd_nonblock(cl->wpipe.fd);
525 /* close unneeded pipe ends */
529 D("CGI: Child(%d) created: rfd(%d) wfd(%d)\n", child, rfd[0], wfd[1]);
531 state->httpbuf.ptr = state->httpbuf.buf;
532 state->httpbuf.len = sizeof(state->httpbuf.buf);
534 state->content_length = cl->httpbuf.len;
536 /* find content length */
537 if (req->method == UH_HTTP_MSG_POST)
539 foreach_header(i, req->headers)
541 if (!strcasecmp(req->headers[i], "Content-Length"))
543 state->content_length = atoi(req->headers[i+1]);
549 cl->cb = uh_cgi_socket_cb;