client.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd
   3  *
   4  *   Copyright (C) 2010-2012 Jo-Philipp Wich <xm@subsignal.org>
   5  *   Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
   6  *
   7  *  Licensed under the Apache License, Version 2.0 (the "License");
   8  *  you may not use this file except in compliance with the License.
   9  *  You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  *  Unless required by applicable law or agreed to in writing, software
  14  *  distributed under the License is distributed on an "AS IS" BASIS,
  15  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  *  See the License for the specific language governing permissions and
  17  *  limitations under the License.
  18  */
  19
  20 #include <libubox/blobmsg.h>
  21 #include <ctype.h>
  22
  23 #include "uhttpd.h"
  24
  25 static LIST_HEAD(clients);
  26
  27 int n_clients = 0;
  28 struct config conf = {};
  29
  30 static const char *http_versions[] = {
  31         [UH_HTTP_VER_0_9] = "HTTP/0.9",
  32         [UH_HTTP_VER_1_0] = "HTTP/1.0",
  33         [UH_HTTP_VER_1_1] = "HTTP/1.1",
  34 };
  35
  36 void uh_http_header(struct client *cl, int code, const char *summary)
  37 {
  38         const char *enc = "Transfer-Encoding: chunked\r\n";
  39         const char *conn;
  40
  41         if (!uh_use_chunked(cl))
  42                 enc = "";
  43
  44         if (cl->request.version != UH_HTTP_VER_1_1)
  45                 conn = "Connection: close";
  46         else
  47                 conn = "Connection: keep-alive";
  48
  49         ustream_printf(cl->us, "%s %03i %s\r\n%s\r\n%s",
  50                 http_versions[cl->request.version],
  51                 code, summary, conn, enc);
  52 }
  53
  54 static void uh_connection_close(struct client *cl)
  55 {
  56         cl->state = CLIENT_STATE_DONE;
  57         cl->us->eof = true;
  58         ustream_state_change(cl->us);
  59 }
  60
  61 static void uh_dispatch_done(struct client *cl)
  62 {
  63         if (cl->dispatch.free)
  64                 cl->dispatch.free(cl);
  65 }
  66
  67 void uh_request_done(struct client *cl)
  68 {
  69         uh_chunk_eof(cl);
  70         uh_dispatch_done(cl);
  71         cl->us->notify_write = NULL;
  72         memset(&cl->dispatch, 0, sizeof(cl->dispatch));
  73
  74         if (cl->request.version != UH_HTTP_VER_1_1 || !conf.http_keepalive) {
  75                 uh_connection_close(cl);
  76                 return;
  77         }
  78
  79         cl->state = CLIENT_STATE_INIT;
  80         uloop_timeout_set(&cl->timeout, conf.http_keepalive * 1000);
  81 }
  82
  83 void __printf(4, 5)
  84 uh_client_error(struct client *cl, int code, const char *summary, const char *fmt, ...)
  85 {
  86         va_list arg;
  87
  88         uh_http_header(cl, code, summary);
  89         ustream_printf(cl->us, "Content-Type: text/html\r\n\r\n");
  90
  91         uh_chunk_printf(cl, "<h1>%s</h1>", summary);
  92
  93         if (fmt) {
  94                 va_start(arg, fmt);
  95                 uh_chunk_vprintf(cl, fmt, arg);
  96                 va_end(arg);
  97         }
  98
  99         uh_request_done(cl);
 100 }
 101
 102 static void uh_header_error(struct client *cl, int code, const char *summary)
 103 {
 104         uh_client_error(cl, code, summary, NULL);
 105         uh_connection_close(cl);
 106 }
 107
 108 static void client_timeout(struct uloop_timeout *timeout)
 109 {
 110         struct client *cl = container_of(timeout, struct client, timeout);
 111
 112         cl->state = CLIENT_STATE_CLOSE;
 113         uh_connection_close(cl);
 114 }
 115
 116 static int client_parse_request(struct client *cl, char *data)
 117 {
 118         struct http_request *req = &cl->request;
 119         char *type, *path, *version;
 120         int i;
 121
 122         type = strtok(data, " ");
 123         path = strtok(NULL, " ");
 124         version = strtok(NULL, " ");
 125         if (!type || !path || !version)
 126                 return CLIENT_STATE_DONE;
 127
 128         req->url = path;
 129         if (!strcmp(type, "GET"))
 130                 req->method = UH_HTTP_MSG_GET;
 131         else if (!strcmp(type, "POST"))
 132                 req->method = UH_HTTP_MSG_POST;
 133         else if (!strcmp(type, "HEAD"))
 134                 req->method = UH_HTTP_MSG_HEAD;
 135         else
 136                 return CLIENT_STATE_DONE;
 137
 138         cl->request.version = -1;
 139         i = array_size(http_versions);
 140         while (i--) {
 141                 if (!strcmp(version, http_versions[i])) {
 142                         cl->request.version = i;
 143                         break;
 144                 }
 145         }
 146         if (cl->request.version < 0)
 147                 return CLIENT_STATE_DONE;
 148
 149         return CLIENT_STATE_HEADER;
 150 }
 151
 152 static bool client_init_cb(struct client *cl, char *buf, int len)
 153 {
 154         char *newline;
 155
 156         newline = strstr(buf, "\r\n");
 157         if (!newline)
 158                 return false;
 159
 160         *newline = 0;
 161         blob_buf_init(&cl->hdr, 0);
 162         blobmsg_add_string(&cl->hdr, "REQUEST", buf);
 163         ustream_consume(cl->us, newline + 2 - buf);
 164         cl->state = client_parse_request(cl, (char *) blobmsg_data(blob_data(cl->hdr.head)));
 165         if (cl->state == CLIENT_STATE_DONE)
 166                 uh_header_error(cl, 400, "Bad Request");
 167
 168         return true;
 169 }
 170
 171 static void client_header_complete(struct client *cl)
 172 {
 173         uh_handle_file_request(cl);
 174 }
 175
 176 static int client_parse_header(struct client *cl, char *data)
 177 {
 178         char *name;
 179         char *val;
 180
 181         if (!*data) {
 182                 uloop_timeout_cancel(&cl->timeout);
 183                 client_header_complete(cl);
 184                 return CLIENT_STATE_DATA;
 185         }
 186
 187         val = strchr(data, ':');
 188         if (!val)
 189                 return CLIENT_STATE_DONE;
 190
 191         *val = 0;
 192         val++;
 193
 194         while (isspace(*val))
 195                 val++;
 196
 197         for (name = data; *name; name++)
 198                 if (isupper(*name))
 199                         *name = tolower(*name);
 200
 201         blobmsg_add_string(&cl->hdr, data, val);
 202
 203         return CLIENT_STATE_HEADER;
 204 }
 205
 206 static bool client_data_cb(struct client *cl, char *buf, int len)
 207 {
 208         return false;
 209 }
 210
 211 static bool client_header_cb(struct client *cl, char *buf, int len)
 212 {
 213         char *newline;
 214         int line_len;
 215
 216         newline = strstr(buf, "\r\n");
 217         if (!newline)
 218                 return false;
 219
 220         *newline = 0;
 221         cl->state = client_parse_header(cl, buf);
 222         line_len = newline + 2 - buf;
 223         ustream_consume(cl->us, line_len);
 224         if (cl->state == CLIENT_STATE_DATA)
 225                 client_data_cb(cl, newline + 2, len - line_len);
 226
 227         return true;
 228 }
 229
 230 typedef bool (*read_cb_t)(struct client *cl, char *buf, int len);
 231 static read_cb_t read_cbs[] = {
 232         [CLIENT_STATE_INIT] = client_init_cb,
 233         [CLIENT_STATE_HEADER] = client_header_cb,
 234         [CLIENT_STATE_DATA] = client_data_cb,
 235 };
 236
 237 static void client_read_cb(struct client *cl)
 238 {
 239         struct ustream *us = cl->us;
 240         char *str;
 241         int len;
 242
 243         do {
 244                 str = ustream_get_read_buf(us, &len);
 245                 if (!str)
 246                         break;
 247
 248                 if (cl->state >= array_size(read_cbs) || !read_cbs[cl->state])
 249                         break;
 250
 251                 if (!read_cbs[cl->state](cl, str, len)) {
 252                         if (len == us->r.buffer_len)
 253                                 uh_header_error(cl, 413, "Request Entity Too Large");
 254                         break;
 255                 }
 256         } while(1);
 257 }
 258
 259 static void client_close(struct client *cl)
 260 {
 261         uh_dispatch_done(cl);
 262         uloop_timeout_cancel(&cl->timeout);
 263         ustream_free(&cl->sfd.stream);
 264         close(cl->sfd.fd.fd);
 265         list_del(&cl->list);
 266         free(cl);
 267
 268         uh_unblock_listeners();
 269 }
 270
 271 static void client_ustream_read_cb(struct ustream *s, int bytes)
 272 {
 273         struct client *cl = container_of(s, struct client, sfd);
 274
 275         client_read_cb(cl);
 276 }
 277
 278 static void client_ustream_write_cb(struct ustream *s, int bytes)
 279 {
 280         struct client *cl = container_of(s, struct client, sfd);
 281
 282         if (cl->dispatch.write_cb)
 283                 cl->dispatch.write_cb(cl);
 284 }
 285
 286 static void client_notify_state(struct ustream *s)
 287 {
 288         struct client *cl = container_of(s, struct client, sfd);
 289
 290         if (cl->state == CLIENT_STATE_CLOSE ||
 291                 (s->eof && !s->w.data_bytes) || s->write_error)
 292                 return client_close(cl);
 293 }
 294
 295 void uh_accept_client(int fd)
 296 {
 297         static struct client *next_client;
 298         struct client *cl;
 299         unsigned int sl;
 300         int sfd;
 301         static int client_id = 0;
 302
 303         if (!next_client)
 304                 next_client = calloc(1, sizeof(*next_client));
 305
 306         cl = next_client;
 307
 308         sl = sizeof(cl->peeraddr);
 309         sfd = accept(fd, (struct sockaddr *) &cl->peeraddr, &sl);
 310         if (sfd < 0)
 311                 return;
 312
 313         sl = sizeof(cl->servaddr);
 314         getsockname(fd, (struct sockaddr *) &cl->servaddr, &sl);
 315         cl->us = &cl->sfd.stream;
 316         cl->us->string_data = true;
 317         cl->us->notify_read = client_ustream_read_cb;
 318         cl->us->notify_write = client_ustream_write_cb;
 319         cl->us->notify_state = client_notify_state;
 320         ustream_fd_init(&cl->sfd, sfd);
 321
 322         cl->timeout.cb = client_timeout;
 323         uloop_timeout_set(&cl->timeout, conf.network_timeout * 1000);
 324
 325         list_add_tail(&cl->list, &clients);
 326
 327         next_client = NULL;
 328         n_clients++;
 329         cl->id = client_id++;
 330 }
 331
 332 void uh_close_fds(void)
 333 {
 334         struct client *cl;
 335
 336         uloop_done();
 337         uh_close_listen_fds();
 338         list_for_each_entry(cl, &clients, list) {
 339                 close(cl->sfd.fd.fd);
 340                 if (cl->dispatch.close_fds)
 341                         cl->dispatch.close_fds(cl);
 342         }
 343 }