src/afb-hsrv.c

   1 /*
   2  * Copyright 2016 IoT.bzh
   3  * Author: José Bollo <jose.bollo@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #define _GNU_SOURCE
  19
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <assert.h>
  23 #include <poll.h>
  24 #include <fcntl.h>
  25 #include <sys/stat.h>
  26
  27 #include <microhttpd.h>
  28
  29 #include "afb-method.h"
  30 #include "afb-hreq.h"
  31 #include "afb-hsrv.h"
  32 #include "afb-req-itf.h"
  33 #include "verbose.h"
  34 #include "utils-upoll.h"
  35
  36
  37 #define JSON_CONTENT  "application/json"
  38 #define FORM_CONTENT  MHD_HTTP_POST_ENCODING_MULTIPART_FORMDATA
  39
  40
  41 struct hsrv_handler {
  42         struct hsrv_handler *next;
  43         const char *prefix;
  44         size_t length;
  45         int (*handler) (struct afb_hreq *, void *);
  46         void *data;
  47         int priority;
  48 };
  49
  50 struct hsrv_alias {
  51         const char *alias;
  52         const char *directory;
  53         size_t lendir;
  54         int dirfd;
  55 };
  56
  57 struct afb_hsrv {
  58         unsigned refcount;
  59         struct hsrv_handler *handlers;
  60         struct MHD_Daemon *httpd;
  61         struct upoll *upoll;
  62         int in_run;
  63         char *cache_to;
  64 };
  65
  66 static int global_reqids = 0;
  67
  68 static void reply_error(struct MHD_Connection *connection, unsigned int status)
  69 {
  70         struct MHD_Response *response = MHD_create_response_from_buffer(0, NULL, MHD_RESPMEM_PERSISTENT);
  71         MHD_queue_response(connection, status, response);
  72         MHD_destroy_response(response);
  73 }
  74
  75 static int postproc(void *cls,
  76                     enum MHD_ValueKind kind,
  77                     const char *key,
  78                     const char *filename,
  79                     const char *content_type,
  80                     const char *transfer_encoding,
  81                     const char *data,
  82                     uint64_t off,
  83                     size_t size)
  84 {
  85         struct afb_hreq *hreq = cls;
  86         if (filename != NULL)
  87                 return afb_hreq_post_add_file(hreq, key, filename, data, size);
  88         else
  89                 return afb_hreq_post_add(hreq, key, data, size);
  90 }
  91
  92 static int access_handler(
  93                 void *cls,
  94                 struct MHD_Connection *connection,
  95                 const char *url,
  96                 const char *methodstr,
  97                 const char *version,
  98                 const char *upload_data,
  99                 size_t *upload_data_size,
 100                 void **recordreq)
 101 {
 102         int rc;
 103         struct afb_hreq *hreq;
 104         enum afb_method method;
 105         struct afb_hsrv *hsrv;
 106         struct hsrv_handler *iter;
 107         const char *type;
 108
 109         hsrv = cls;
 110         hreq = *recordreq;
 111         if (hreq == NULL) {
 112                 /* get the method */
 113                 method = get_method(methodstr);
 114                 method &= afb_method_get | afb_method_post;
 115                 if (method == afb_method_none) {
 116                         reply_error(connection, MHD_HTTP_BAD_REQUEST);
 117                         return MHD_YES;
 118                 }
 119
 120                 /* create the request */
 121                 hreq = calloc(1, sizeof *hreq);
 122                 if (hreq == NULL) {
 123                         reply_error(connection, MHD_HTTP_INTERNAL_SERVER_ERROR);
 124                         return MHD_YES;
 125                 }
 126
 127                 /* init the request */
 128                 hreq->hsrv = hsrv;
 129                 hreq->cacheTimeout = hsrv->cache_to;
 130                 hreq->reqid = ++global_reqids;
 131                 hreq->scanned = 0;
 132                 hreq->suspended = 0;
 133                 hreq->replied = 0;
 134                 hreq->connection = connection;
 135                 hreq->method = method;
 136                 hreq->version = version;
 137                 hreq->tail = hreq->url = url;
 138                 hreq->lentail = hreq->lenurl = strlen(url);
 139                 *recordreq = hreq;
 140
 141                 /* init the post processing */
 142                 if (method == afb_method_post) {
 143                         type = afb_hreq_get_header(hreq, MHD_HTTP_HEADER_CONTENT_TYPE);
 144                         if (type == NULL) {
 145                                 /* an empty post, let's process it as a get */
 146                                 hreq->method = afb_method_get;
 147                         } else if (strcasestr(type, FORM_CONTENT) != NULL) {
 148                                 hreq->postform = MHD_create_post_processor (connection, 65500, postproc, hreq);
 149                                 if (hreq->postform == NULL)
 150                                         afb_hreq_reply_error(hreq, MHD_HTTP_INTERNAL_SERVER_ERROR);
 151                                 return MHD_YES;
 152                         } else if (strcasestr(type, JSON_CONTENT) == NULL) {
 153                                 afb_hreq_reply_error(hreq, MHD_HTTP_UNSUPPORTED_MEDIA_TYPE);
 154                                 return MHD_YES;
 155                         }
 156                 }
 157         }
 158
 159         /* process further data */
 160         if (*upload_data_size) {
 161                 if (hreq->postform != NULL) {
 162                         if (!MHD_post_process (hreq->postform, upload_data, *upload_data_size)) {
 163                                 afb_hreq_reply_error(hreq, MHD_HTTP_INTERNAL_SERVER_ERROR);
 164                                 return MHD_YES;
 165                         }
 166                 } else {
 167                         if (!afb_hreq_post_add(hreq, "", upload_data, *upload_data_size)) {
 168                                 afb_hreq_reply_error(hreq, MHD_HTTP_INTERNAL_SERVER_ERROR);
 169                                 return MHD_YES;
 170                         }
 171                 }
 172                 *upload_data_size = 0;
 173                 return MHD_YES;
 174         }
 175
 176         /* flush the data */
 177         if (hreq->postform != NULL) {
 178                 rc = MHD_destroy_post_processor(hreq->postform);
 179                 hreq->postform = NULL;
 180                 if (rc == MHD_NO) {
 181                         afb_hreq_reply_error(hreq, MHD_HTTP_BAD_REQUEST);
 182                         return MHD_YES;
 183                 }
 184         }
 185
 186         if (hreq->scanned != 0) {
 187                 if (hreq->replied == 0 && hreq->suspended == 0) {
 188                         MHD_suspend_connection (connection);
 189                         hreq->suspended = 1;
 190                 }
 191                 return MHD_YES;
 192         }
 193
 194         /* search an handler for the request */
 195         hreq->scanned = 1;
 196         iter = hsrv->handlers;
 197         while (iter) {
 198                 if (afb_hreq_unprefix(hreq, iter->prefix, iter->length)) {
 199                         if (iter->handler(hreq, iter->data)) {
 200                                 if (hreq->replied == 0 && hreq->suspended == 0) {
 201                                         MHD_suspend_connection (connection);
 202                                         hreq->suspended = 1;
 203                                 }
 204                                 return MHD_YES;
 205                         }
 206                         hreq->tail = hreq->url;
 207                         hreq->lentail = hreq->lenurl;
 208                 }
 209                 iter = iter->next;
 210         }
 211
 212         /* no handler */
 213         afb_hreq_reply_error(hreq, MHD_HTTP_NOT_FOUND);
 214         return MHD_YES;
 215 }
 216
 217 /* Because of POST call multiple time requestApi we need to free POST handle here */
 218 static void end_handler(void *cls, struct MHD_Connection *connection, void **recordreq,
 219                         enum MHD_RequestTerminationCode toe)
 220 {
 221         struct afb_hreq *hreq;
 222
 223         hreq = *recordreq;
 224         if (hreq->upgrade)
 225                 MHD_suspend_connection (connection);
 226         afb_hreq_free(hreq);
 227 }
 228
 229 void run_micro_httpd(struct afb_hsrv *hsrv)
 230 {
 231         if (hsrv->in_run != 0)
 232                 hsrv->in_run = 2;
 233         else {
 234                 upoll_on_readable(hsrv->upoll, NULL);
 235                 do {
 236                         hsrv->in_run = 1;
 237                         MHD_run(hsrv->httpd);
 238                 } while(hsrv->in_run == 2);
 239                 hsrv->in_run = 0;
 240                 upoll_on_readable(hsrv->upoll, (void*)run_micro_httpd);
 241         }
 242 };
 243
 244 static int new_client_handler(void *cls, const struct sockaddr *addr, socklen_t addrlen)
 245 {
 246         return MHD_YES;
 247 }
 248
 249 static struct hsrv_handler *new_handler(
 250                 struct hsrv_handler *head,
 251                 const char *prefix,
 252                 int (*handler) (struct afb_hreq *, void *),
 253                 void *data,
 254                 int priority)
 255 {
 256         struct hsrv_handler *link, *iter, *previous;
 257         size_t length;
 258
 259         /* get the length of the prefix without its leading / */
 260         length = strlen(prefix);
 261         while (length && prefix[length - 1] == '/')
 262                 length--;
 263
 264         /* allocates the new link */
 265         link = malloc(sizeof *link);
 266         if (link == NULL)
 267                 return NULL;
 268
 269         /* initialize it */
 270         link->prefix = prefix;
 271         link->length = length;
 272         link->handler = handler;
 273         link->data = data;
 274         link->priority = priority;
 275
 276         /* adds it */
 277         previous = NULL;
 278         iter = head;
 279         while (iter && (priority < iter->priority || (priority == iter->priority && length <= iter->length))) {
 280                 previous = iter;
 281                 iter = iter->next;
 282         }
 283         link->next = iter;
 284         if (previous == NULL)
 285                 return link;
 286         previous->next = link;
 287         return head;
 288 }
 289
 290 static int handle_alias(struct afb_hreq *hreq, void *data)
 291 {
 292         struct hsrv_alias *da = data;
 293
 294         if (hreq->method != afb_method_get) {
 295                 afb_hreq_reply_error(hreq, MHD_HTTP_METHOD_NOT_ALLOWED);
 296                 return 1;
 297         }
 298
 299         if (!afb_hreq_valid_tail(hreq)) {
 300                 afb_hreq_reply_error(hreq, MHD_HTTP_FORBIDDEN);
 301                 return 1;
 302         }
 303
 304         return afb_hreq_reply_file(hreq, da->dirfd, &hreq->tail[1]);
 305 }
 306
 307 int afb_hsrv_add_handler(
 308                 struct afb_hsrv *hsrv,
 309                 const char *prefix,
 310                 int (*handler) (struct afb_hreq *, void *),
 311                 void *data,
 312                 int priority)
 313 {
 314         struct hsrv_handler *head;
 315
 316         head = new_handler(hsrv->handlers, prefix, handler, data, priority);
 317         if (head == NULL)
 318                 return 0;
 319         hsrv->handlers = head;
 320         return 1;
 321 }
 322
 323 int afb_hsrv_add_alias(struct afb_hsrv *hsrv, const char *prefix, const char *alias, int priority)
 324 {
 325         struct hsrv_alias *da;
 326         int dirfd;
 327
 328         dirfd = open(alias, O_PATH|O_DIRECTORY);
 329         if (dirfd < 0) {
 330                 /* TODO message */
 331                 return 0;
 332         }
 333         da = malloc(sizeof *da);
 334         if (da != NULL) {
 335                 da->alias = prefix;
 336                 da->directory = alias;
 337                 da->lendir = strlen(da->directory);
 338                 da->dirfd = dirfd;
 339                 if (afb_hsrv_add_handler(hsrv, prefix, handle_alias, da, priority))
 340                         return 1;
 341                 free(da);
 342         }
 343         close(dirfd);
 344         return 0;
 345 }
 346
 347 int afb_hsrv_set_cache_timeout(struct afb_hsrv *hsrv, int duration)
 348 {
 349         int rc;
 350         char *dur;
 351
 352         rc = asprintf(&dur, "%d", duration);
 353         if (rc < 0)
 354                 return 0;
 355
 356         free(hsrv->cache_to);
 357         hsrv->cache_to = dur;
 358         return 1;
 359 }
 360
 361 int afb_hsrv_start(struct afb_hsrv *hsrv, uint16_t port, unsigned int connection_timeout)
 362 {
 363         struct upoll *upoll;
 364         struct MHD_Daemon *httpd;
 365         const union MHD_DaemonInfo *info;
 366
 367         httpd = MHD_start_daemon(
 368                 MHD_USE_EPOLL_LINUX_ONLY | MHD_USE_TCP_FASTOPEN | MHD_USE_DEBUG | MHD_USE_SUSPEND_RESUME,
 369                 port,                           /* port */
 370                 new_client_handler, NULL,       /* Tcp Accept call back + extra attribute */
 371                 access_handler, hsrv,   /* Http Request Call back + extra attribute */
 372                 MHD_OPTION_NOTIFY_COMPLETED, end_handler, hsrv,
 373                 MHD_OPTION_CONNECTION_TIMEOUT, connection_timeout,
 374                 MHD_OPTION_END);        /* options-end */
 375
 376         if (httpd == NULL) {
 377                 fprintf(stderr, "Error: httpStart invalid httpd port: %d", (int)port);
 378                 return 0;
 379         }
 380
 381         info = MHD_get_daemon_info(httpd, MHD_DAEMON_INFO_EPOLL_FD_LINUX_ONLY);
 382         if (info == NULL) {
 383                 MHD_stop_daemon(httpd);
 384                 fprintf(stderr, "Error: httpStart no pollfd");
 385                 return 0;
 386         }
 387
 388         upoll = upoll_open(info->listen_fd, hsrv);
 389         if (upoll == NULL) {
 390                 MHD_stop_daemon(httpd);
 391                 fprintf(stderr, "Error: connection to upoll of httpd failed");
 392                 return 0;
 393         }
 394         upoll_on_readable(upoll, (void*)run_micro_httpd);
 395
 396         hsrv->httpd = httpd;
 397         hsrv->upoll = upoll;
 398         return 1;
 399 }
 400
 401 void afb_hsrv_stop(struct afb_hsrv *hsrv)
 402 {
 403         if (hsrv->upoll)
 404                 upoll_close(hsrv->upoll);
 405         hsrv->upoll = NULL;
 406         if (hsrv->httpd != NULL)
 407                 MHD_stop_daemon(hsrv->httpd);
 408         hsrv->httpd = NULL;
 409 }
 410
 411 struct afb_hsrv *afb_hsrv_create()
 412 {
 413         struct afb_hsrv *result = calloc(1, sizeof(struct afb_hsrv));
 414         if (result != NULL)
 415                 result->refcount = 1;
 416         return result;
 417 }
 418
 419 void afb_hsrv_put(struct afb_hsrv *hsrv)
 420 {
 421         assert(hsrv->refcount != 0);
 422         if (!--hsrv->refcount) {
 423                 afb_hsrv_stop(hsrv);
 424                 free(hsrv);
 425         }
 426 }
 427