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_client_error_header(struct client *cl, int code, const char *summary)
  55 {
  56         uh_http_header(cl, code, summary);
  57         ustream_printf(cl->us, "Content-Type: text/plain\r\n\r\n");
  58 }
  59
  60 static void uh_connection_close(struct client *cl)
  61 {
  62         cl->state = CLIENT_STATE_DONE;
  63         cl->us->eof = true;
  64         ustream_state_change(cl->us);
  65 }
  66
  67 static void uh_dispatch_done(struct client *cl)
  68 {
  69         if (cl->dispatch_free)
  70                 cl->dispatch_free(cl);
  71         cl->dispatch_free = NULL;
  72 }
  73
  74 void uh_request_done(struct client *cl)
  75 {
  76         uh_chunk_eof(cl);
  77         uh_dispatch_done(cl);
  78         cl->us->notify_write = NULL;
  79         memset(&cl->data, 0, sizeof(cl->data));
  80
  81         if (cl->request.version != UH_HTTP_VER_1_1 || !conf.http_keepalive) {
  82                 uh_connection_close(cl);
  83                 return;
  84         }
  85
  86         cl->state = CLIENT_STATE_INIT;
  87         uloop_timeout_set(&cl->timeout, conf.http_keepalive * 1000);
  88 }
  89
  90 void __printf(4, 5)
  91 uh_client_error(struct client *cl, int code, const char *summary, const char *fmt, ...)
  92 {
  93         va_list arg;
  94
  95         uh_client_error_header(cl, code, summary);
  96
  97         va_start(arg, fmt);
  98         uh_chunk_vprintf(cl, fmt, arg);
  99         va_end(arg);
 100
 101         uh_request_done(cl);
 102 }
 103
 104 static void uh_header_error(struct client *cl, int code, const char *summary)
 105 {
 106         uh_client_error(cl, code, summary, "%s", summary);
 107         uh_connection_close(cl);
 108 }
 109
 110 static void client_timeout(struct uloop_timeout *timeout)
 111 {
 112         struct client *cl = container_of(timeout, struct client, timeout);
 113
 114         cl->state = CLIENT_STATE_CLOSE;
 115         uh_connection_close(cl);
 116 }
 117
 118 static int client_parse_request(struct client *cl, char *data)
 119 {
 120         struct http_request *req = &cl->request;
 121         char *type, *path, *version;
 122         int i;
 123
 124         type = strtok(data, " ");
 125         path = strtok(NULL, " ");
 126         version = strtok(NULL, " ");
 127         if (!type || !path || !version)
 128                 return CLIENT_STATE_DONE;
 129
 130         req->url = path;
 131         if (!strcmp(type, "GET"))
 132                 req->method = UH_HTTP_MSG_GET;
 133         else if (!strcmp(type, "POST"))
 134                 req->method = UH_HTTP_MSG_POST;
 135         else if (!strcmp(type, "HEAD"))
 136                 req->method = UH_HTTP_MSG_HEAD;
 137         else
 138                 return CLIENT_STATE_DONE;
 139
 140         cl->request.version = -1;
 141         i = array_size(http_versions);
 142         while (i--) {
 143                 if (!strcmp(version, http_versions[i])) {
 144                         cl->request.version = i;
 145                         break;
 146                 }
 147         }
 148         if (cl->request.version < 0)
 149                 return CLIENT_STATE_DONE;
 150
 151         return CLIENT_STATE_HEADER;
 152 }
 153
 154 static bool client_init_cb(struct client *cl, char *buf, int len)
 155 {
 156         char *newline;
 157
 158         newline = strstr(buf, "\r\n");
 159         if (!newline)
 160                 return false;
 161
 162         *newline = 0;
 163         blob_buf_init(&cl->hdr, 0);
 164         blobmsg_add_string(&cl->hdr, "REQUEST", buf);
 165         ustream_consume(cl->us, newline + 2 - buf);
 166         cl->state = client_parse_request(cl, (char *) blobmsg_data(blob_data(cl->hdr.head)));
 167         if (cl->state == CLIENT_STATE_DONE)
 168                 uh_header_error(cl, 400, "Bad Request");
 169
 170         return true;
 171 }
 172
 173 static void client_header_complete(struct client *cl)
 174 {
 175         uh_handle_file_request(cl);
 176 }
 177
 178 static int client_parse_header(struct client *cl, char *data)
 179 {
 180         char *name;
 181         char *val;
 182
 183         if (!*data) {
 184                 uloop_timeout_cancel(&cl->timeout);
 185                 client_header_complete(cl);
 186                 return CLIENT_STATE_DATA;
 187         }
 188
 189         val = strchr(data, ':');
 190         if (!val)
 191                 return CLIENT_STATE_DONE;
 192
 193         *val = 0;
 194         val++;
 195
 196         while (isspace(*val))
 197                 val++;
 198
 199         for (name = data; *name; name++)
 200                 if (isupper(*name))
 201                         *name = tolower(*name);
 202
 203         blobmsg_add_string(&cl->hdr, data, val);
 204
 205         return CLIENT_STATE_HEADER;
 206 }
 207
 208 static bool client_data_cb(struct client *cl, char *buf, int len)
 209 {
 210         return false;
 211 }
 212
 213 static bool client_header_cb(struct client *cl, char *buf, int len)
 214 {
 215         char *newline;
 216         int line_len;
 217
 218         newline = strstr(buf, "\r\n");
 219         if (!newline)
 220                 return false;
 221
 222         *newline = 0;
 223         cl->state = client_parse_header(cl, buf);
 224         line_len = newline + 2 - buf;
 225         ustream_consume(cl->us, line_len);
 226         if (cl->state == CLIENT_STATE_DATA)
 227                 client_data_cb(cl, newline + 2, len - line_len);
 228
 229         return true;
 230 }
 231
 232 typedef bool (*read_cb_t)(struct client *cl, char *buf, int len);
 233 static read_cb_t read_cbs[] = {
 234         [CLIENT_STATE_INIT] = client_init_cb,
 235         [CLIENT_STATE_HEADER] = client_header_cb,
 236         [CLIENT_STATE_DATA] = client_data_cb,
 237 };
 238
 239 static void client_read_cb(struct client *cl)
 240 {
 241         struct ustream *us = cl->us;
 242         char *str;
 243         int len;
 244
 245         do {
 246                 str = ustream_get_read_buf(us, &len);
 247                 if (!str)
 248                         break;
 249
 250                 if (cl->state >= array_size(read_cbs) || !read_cbs[cl->state])
 251                         break;
 252
 253                 if (!read_cbs[cl->state](cl, str, len)) {
 254                         if (len == us->r.buffer_len)
 255                                 uh_header_error(cl, 413, "Request Entity Too Large");
 256                         break;
 257                 }
 258         } while(1);
 259 }
 260
 261 static void client_close(struct client *cl)
 262 {
 263         uh_dispatch_done(cl);
 264         uloop_timeout_cancel(&cl->timeout);
 265         ustream_free(&cl->sfd.stream);
 266         close(cl->sfd.fd.fd);
 267         list_del(&cl->list);
 268         free(cl);
 269
 270         uh_unblock_listeners();
 271 }
 272
 273 static void client_ustream_read_cb(struct ustream *s, int bytes)
 274 {
 275         struct client *cl = container_of(s, struct client, sfd);
 276
 277         client_read_cb(cl);
 278 }
 279
 280 static void client_ustream_write_cb(struct ustream *s, int bytes)
 281 {
 282         struct client *cl = container_of(s, struct client, sfd);
 283
 284         if (cl->dispatch_write_cb)
 285                 cl->dispatch_write_cb(cl);
 286 }
 287
 288 static void client_notify_state(struct ustream *s)
 289 {
 290         struct client *cl = container_of(s, struct client, sfd);
 291
 292         if (cl->state == CLIENT_STATE_CLOSE ||
 293                 (s->eof && !s->w.data_bytes) || s->write_error)
 294                 return client_close(cl);
 295 }
 296
 297 void uh_accept_client(int fd)
 298 {
 299         static struct client *next_client;
 300         struct client *cl;
 301         unsigned int sl;
 302         int sfd;
 303         static int client_id = 0;
 304
 305         if (!next_client)
 306                 next_client = calloc(1, sizeof(*next_client));
 307
 308         cl = next_client;
 309
 310         sl = sizeof(cl->peeraddr);
 311         sfd = accept(fd, (struct sockaddr *) &cl->peeraddr, &sl);
 312         if (sfd < 0)
 313                 return;
 314
 315         sl = sizeof(cl->servaddr);
 316         getsockname(fd, (struct sockaddr *) &cl->servaddr, &sl);
 317         cl->us = &cl->sfd.stream;
 318         cl->us->string_data = true;
 319         cl->us->notify_read = client_ustream_read_cb;
 320         cl->us->notify_write = client_ustream_write_cb;
 321         cl->us->notify_state = client_notify_state;
 322         ustream_fd_init(&cl->sfd, sfd);
 323
 324         cl->timeout.cb = client_timeout;
 325         uloop_timeout_set(&cl->timeout, conf.network_timeout * 1000);
 326
 327         list_add_tail(&cl->list, &clients);
 328
 329         next_client = NULL;
 330         n_clients++;
 331         cl->id = client_id++;
 332 }