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         cl->dispatch_free = NULL;
  66 }
  67
  68 void uh_request_done(struct client *cl)
  69 {
  70         uh_chunk_eof(cl);
  71         uh_dispatch_done(cl);
  72         cl->us->notify_write = NULL;
  73         memset(&cl->data, 0, sizeof(cl->data));
  74
  75         if (cl->request.version != UH_HTTP_VER_1_1 || !conf.http_keepalive) {
  76                 uh_connection_close(cl);
  77                 return;
  78         }
  79
  80         cl->state = CLIENT_STATE_INIT;
  81         uloop_timeout_set(&cl->timeout, conf.http_keepalive * 1000);
  82 }
  83
  84 void __printf(4, 5)
  85 uh_client_error(struct client *cl, int code, const char *summary, const char *fmt, ...)
  86 {
  87         va_list arg;
  88
  89         uh_http_header(cl, code, summary);
  90         ustream_printf(cl->us, "Content-Type: text/html\r\n\r\n");
  91
  92         uh_chunk_printf(cl, "<h1>%s</h1>", summary);
  93
  94         if (fmt) {
  95                 va_start(arg, fmt);
  96                 uh_chunk_vprintf(cl, fmt, arg);
  97                 va_end(arg);
  98         }
  99
 100         uh_request_done(cl);
 101 }
 102
 103 static void uh_header_error(struct client *cl, int code, const char *summary)
 104 {
 105         uh_client_error(cl, code, summary, NULL);
 106         uh_connection_close(cl);
 107 }
 108
 109 static void client_timeout(struct uloop_timeout *timeout)
 110 {
 111         struct client *cl = container_of(timeout, struct client, timeout);
 112
 113         cl->state = CLIENT_STATE_CLOSE;
 114         uh_connection_close(cl);
 115 }
 116
 117 static int client_parse_request(struct client *cl, char *data)
 118 {
 119         struct http_request *req = &cl->request;
 120         char *type, *path, *version;
 121         int i;
 122
 123         type = strtok(data, " ");
 124         path = strtok(NULL, " ");
 125         version = strtok(NULL, " ");
 126         if (!type || !path || !version)
 127                 return CLIENT_STATE_DONE;
 128
 129         req->url = path;
 130         if (!strcmp(type, "GET"))
 131                 req->method = UH_HTTP_MSG_GET;
 132         else if (!strcmp(type, "POST"))
 133                 req->method = UH_HTTP_MSG_POST;
 134         else if (!strcmp(type, "HEAD"))
 135                 req->method = UH_HTTP_MSG_HEAD;
 136         else
 137                 return CLIENT_STATE_DONE;
 138
 139         cl->request.version = -1;
 140         i = array_size(http_versions);
 141         while (i--) {
 142                 if (!strcmp(version, http_versions[i])) {
 143                         cl->request.version = i;
 144                         break;
 145                 }
 146         }
 147         if (cl->request.version < 0)
 148                 return CLIENT_STATE_DONE;
 149
 150         return CLIENT_STATE_HEADER;
 151 }
 152
 153 static bool client_init_cb(struct client *cl, char *buf, int len)
 154 {
 155         char *newline;
 156
 157         newline = strstr(buf, "\r\n");
 158         if (!newline)
 159                 return false;
 160
 161         *newline = 0;
 162         blob_buf_init(&cl->hdr, 0);
 163         blobmsg_add_string(&cl->hdr, "REQUEST", buf);
 164         ustream_consume(cl->us, newline + 2 - buf);
 165         cl->state = client_parse_request(cl, (char *) blobmsg_data(blob_data(cl->hdr.head)));
 166         if (cl->state == CLIENT_STATE_DONE)
 167                 uh_header_error(cl, 400, "Bad Request");
 168
 169         return true;
 170 }
 171
 172 static void client_header_complete(struct client *cl)
 173 {
 174         uh_handle_file_request(cl);
 175 }
 176
 177 static int client_parse_header(struct client *cl, char *data)
 178 {
 179         char *name;
 180         char *val;
 181
 182         if (!*data) {
 183                 uloop_timeout_cancel(&cl->timeout);
 184                 client_header_complete(cl);
 185                 return CLIENT_STATE_DATA;
 186         }
 187
 188         val = strchr(data, ':');
 189         if (!val)
 190                 return CLIENT_STATE_DONE;
 191
 192         *val = 0;
 193         val++;
 194
 195         while (isspace(*val))
 196                 val++;
 197
 198         for (name = data; *name; name++)
 199                 if (isupper(*name))
 200                         *name = tolower(*name);
 201
 202         blobmsg_add_string(&cl->hdr, data, val);
 203
 204         return CLIENT_STATE_HEADER;
 205 }
 206
 207 static bool client_data_cb(struct client *cl, char *buf, int len)
 208 {
 209         return false;
 210 }
 211
 212 static bool client_header_cb(struct client *cl, char *buf, int len)
 213 {
 214         char *newline;
 215         int line_len;
 216
 217         newline = strstr(buf, "\r\n");
 218         if (!newline)
 219                 return false;
 220
 221         *newline = 0;
 222         cl->state = client_parse_header(cl, buf);
 223         line_len = newline + 2 - buf;
 224         ustream_consume(cl->us, line_len);
 225         if (cl->state == CLIENT_STATE_DATA)
 226                 client_data_cb(cl, newline + 2, len - line_len);
 227
 228         return true;
 229 }
 230
 231 typedef bool (*read_cb_t)(struct client *cl, char *buf, int len);
 232 static read_cb_t read_cbs[] = {
 233         [CLIENT_STATE_INIT] = client_init_cb,
 234         [CLIENT_STATE_HEADER] = client_header_cb,
 235         [CLIENT_STATE_DATA] = client_data_cb,
 236 };
 237
 238 static void client_read_cb(struct client *cl)
 239 {
 240         struct ustream *us = cl->us;
 241         char *str;
 242         int len;
 243
 244         do {
 245                 str = ustream_get_read_buf(us, &len);
 246                 if (!str)
 247                         break;
 248
 249                 if (cl->state >= array_size(read_cbs) || !read_cbs[cl->state])
 250                         break;
 251
 252                 if (!read_cbs[cl->state](cl, str, len)) {
 253                         if (len == us->r.buffer_len)
 254                                 uh_header_error(cl, 413, "Request Entity Too Large");
 255                         break;
 256                 }
 257         } while(1);
 258 }
 259
 260 static void client_close(struct client *cl)
 261 {
 262         uh_dispatch_done(cl);
 263         uloop_timeout_cancel(&cl->timeout);
 264         ustream_free(&cl->sfd.stream);
 265         close(cl->sfd.fd.fd);
 266         list_del(&cl->list);
 267         free(cl);
 268
 269         uh_unblock_listeners();
 270 }
 271
 272 static void client_ustream_read_cb(struct ustream *s, int bytes)
 273 {
 274         struct client *cl = container_of(s, struct client, sfd);
 275
 276         client_read_cb(cl);
 277 }
 278
 279 static void client_ustream_write_cb(struct ustream *s, int bytes)
 280 {
 281         struct client *cl = container_of(s, struct client, sfd);
 282
 283         if (cl->dispatch_write_cb)
 284                 cl->dispatch_write_cb(cl);
 285 }
 286
 287 static void client_notify_state(struct ustream *s)
 288 {
 289         struct client *cl = container_of(s, struct client, sfd);
 290
 291         if (cl->state == CLIENT_STATE_CLOSE ||
 292                 (s->eof && !s->w.data_bytes) || s->write_error)
 293                 return client_close(cl);
 294 }
 295
 296 void uh_accept_client(int fd)
 297 {
 298         static struct client *next_client;
 299         struct client *cl;
 300         unsigned int sl;
 301         int sfd;
 302         static int client_id = 0;
 303
 304         if (!next_client)
 305                 next_client = calloc(1, sizeof(*next_client));
 306
 307         cl = next_client;
 308
 309         sl = sizeof(cl->peeraddr);
 310         sfd = accept(fd, (struct sockaddr *) &cl->peeraddr, &sl);
 311         if (sfd < 0)
 312                 return;
 313
 314         sl = sizeof(cl->servaddr);
 315         getsockname(fd, (struct sockaddr *) &cl->servaddr, &sl);
 316         cl->us = &cl->sfd.stream;
 317         cl->us->string_data = true;
 318         cl->us->notify_read = client_ustream_read_cb;
 319         cl->us->notify_write = client_ustream_write_cb;
 320         cl->us->notify_state = client_notify_state;
 321         ustream_fd_init(&cl->sfd, sfd);
 322
 323         cl->timeout.cb = client_timeout;
 324         uloop_timeout_set(&cl->timeout, conf.network_timeout * 1000);
 325
 326         list_add_tail(&cl->list, &clients);
 327
 328         next_client = NULL;
 329         n_clients++;
 330         cl->id = client_id++;
 331 }