src/mod_expire.c

   1 #include "first.h"
   2
   3 #include "base.h"
   4 #include "log.h"
   5 #include "buffer.h"
   6 #include "http_header.h"
   7
   8 #include "plugin.h"
   9 #include "stat_cache.h"
  10
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <time.h>
  14
  15 /**
  16  * this is a expire module for a lighttpd
  17  *
  18  * set 'Expires:' HTTP Headers on demand
  19  */
  20
  21
  22
  23 /* plugin config for all request/connections */
  24
  25 typedef struct {
  26         array *expire_url;
  27         array *expire_mimetypes;
  28 } plugin_config;
  29
  30 typedef struct {
  31         PLUGIN_DATA;
  32
  33         buffer *expire_tstmp;
  34
  35         plugin_config **config_storage;
  36
  37         plugin_config conf;
  38 } plugin_data;
  39
  40 /* init the plugin data */
  41 INIT_FUNC(mod_expire_init) {
  42         plugin_data *p;
  43
  44         p = calloc(1, sizeof(*p));
  45
  46         p->expire_tstmp = buffer_init();
  47
  48         buffer_string_prepare_copy(p->expire_tstmp, 255);
  49
  50         return p;
  51 }
  52
  53 /* detroy the plugin data */
  54 FREE_FUNC(mod_expire_free) {
  55         plugin_data *p = p_d;
  56
  57         UNUSED(srv);
  58
  59         if (!p) return HANDLER_GO_ON;
  60
  61         buffer_free(p->expire_tstmp);
  62
  63         if (p->config_storage) {
  64                 size_t i;
  65                 for (i = 0; i < srv->config_context->used; i++) {
  66                         plugin_config *s = p->config_storage[i];
  67
  68                         if (NULL == s) continue;
  69
  70                         array_free(s->expire_url);
  71                         array_free(s->expire_mimetypes);
  72                         free(s);
  73                 }
  74                 free(p->config_storage);
  75         }
  76
  77         free(p);
  78
  79         return HANDLER_GO_ON;
  80 }
  81
  82 static int mod_expire_get_offset(server *srv, plugin_data *p, buffer *expire, time_t *offset) {
  83         char *ts;
  84         int type = -1;
  85         time_t retts = 0;
  86
  87         UNUSED(p);
  88
  89         /*
  90          * parse
  91          *
  92          * '(access|now|modification) [plus] {<num> <type>}*'
  93          *
  94          * e.g. 'access 1 years'
  95          */
  96
  97         if (buffer_string_is_empty(expire)) {
  98                 log_error_write(srv, __FILE__, __LINE__, "s",
  99                                 "empty:");
 100                 return -1;
 101         }
 102
 103         ts = expire->ptr;
 104
 105         if (0 == strncmp(ts, "access ", 7)) {
 106                 type  = 0;
 107                 ts   += 7;
 108         } else if (0 == strncmp(ts, "now ", 4)) {
 109                 type  = 0;
 110                 ts   += 4;
 111         } else if (0 == strncmp(ts, "modification ", 13)) {
 112                 type  = 1;
 113                 ts   += 13;
 114         } else {
 115                 /* invalid type-prefix */
 116                 log_error_write(srv, __FILE__, __LINE__, "ss",
 117                                 "invalid <base>:", ts);
 118                 return -1;
 119         }
 120
 121         if (0 == strncmp(ts, "plus ", 5)) {
 122                 /* skip the optional plus */
 123                 ts   += 5;
 124         }
 125
 126         /* the rest is just <number> (years|months|weeks|days|hours|minutes|seconds) */
 127         while (1) {
 128                 char *space, *err;
 129                 int num;
 130
 131                 if (NULL == (space = strchr(ts, ' '))) {
 132                         log_error_write(srv, __FILE__, __LINE__, "ss",
 133                                         "missing space after <num>:", ts);
 134                         return -1;
 135                 }
 136
 137                 num = strtol(ts, &err, 10);
 138                 if (*err != ' ') {
 139                         log_error_write(srv, __FILE__, __LINE__, "ss",
 140                                         "missing <type> after <num>:", ts);
 141                         return -1;
 142                 }
 143
 144                 ts = space + 1;
 145
 146                 if (NULL != (space = strchr(ts, ' '))) {
 147                         int slen;
 148                         /* */
 149
 150                         slen = space - ts;
 151
 152                         if (slen == 5 &&
 153                             0 == strncmp(ts, "years", slen)) {
 154                                 num *= 60 * 60 * 24 * 30 * 12;
 155                         } else if (slen == 6 &&
 156                                    0 == strncmp(ts, "months", slen)) {
 157                                 num *= 60 * 60 * 24 * 30;
 158                         } else if (slen == 5 &&
 159                                    0 == strncmp(ts, "weeks", slen)) {
 160                                 num *= 60 * 60 * 24 * 7;
 161                         } else if (slen == 4 &&
 162                                    0 == strncmp(ts, "days", slen)) {
 163                                 num *= 60 * 60 * 24;
 164                         } else if (slen == 5 &&
 165                                    0 == strncmp(ts, "hours", slen)) {
 166                                 num *= 60 * 60;
 167                         } else if (slen == 7 &&
 168                                    0 == strncmp(ts, "minutes", slen)) {
 169                                 num *= 60;
 170                         } else if (slen == 7 &&
 171                                    0 == strncmp(ts, "seconds", slen)) {
 172                                 num *= 1;
 173                         } else {
 174                                 log_error_write(srv, __FILE__, __LINE__, "ss",
 175                                                 "unknown type:", ts);
 176                                 return -1;
 177                         }
 178
 179                         retts += num;
 180
 181                         ts = space + 1;
 182                 } else {
 183                         if (0 == strcmp(ts, "years")) {
 184                                 num *= 60 * 60 * 24 * 30 * 12;
 185                         } else if (0 == strcmp(ts, "months")) {
 186                                 num *= 60 * 60 * 24 * 30;
 187                         } else if (0 == strcmp(ts, "weeks")) {
 188                                 num *= 60 * 60 * 24 * 7;
 189                         } else if (0 == strcmp(ts, "days")) {
 190                                 num *= 60 * 60 * 24;
 191                         } else if (0 == strcmp(ts, "hours")) {
 192                                 num *= 60 * 60;
 193                         } else if (0 == strcmp(ts, "minutes")) {
 194                                 num *= 60;
 195                         } else if (0 == strcmp(ts, "seconds")) {
 196                                 num *= 1;
 197                         } else {
 198                                 log_error_write(srv, __FILE__, __LINE__, "ss",
 199                                                 "unknown type:", ts);
 200                                 return -1;
 201                         }
 202
 203                         retts += num;
 204
 205                         break;
 206                 }
 207         }
 208
 209         if (offset != NULL) *offset = retts;
 210
 211         return type;
 212 }
 213
 214
 215 /* handle plugin config and check values */
 216
 217 SETDEFAULTS_FUNC(mod_expire_set_defaults) {
 218         plugin_data *p = p_d;
 219         size_t i = 0, k;
 220
 221         config_values_t cv[] = {
 222                 { "expire.url",                 NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION },       /* 0 */
 223                 { "expire.mimetypes",           NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION },       /* 1 */
 224                 { NULL,                         NULL, T_CONFIG_UNSET, T_CONFIG_SCOPE_UNSET }
 225         };
 226
 227         if (!p) return HANDLER_ERROR;
 228
 229         p->config_storage = calloc(srv->config_context->used, sizeof(plugin_config *));
 230
 231         for (i = 0; i < srv->config_context->used; i++) {
 232                 data_config const* config = (data_config const*)srv->config_context->data[i];
 233                 plugin_config *s;
 234
 235                 s = calloc(1, sizeof(plugin_config));
 236                 s->expire_url    = array_init();
 237                 s->expire_mimetypes = array_init();
 238
 239                 cv[0].destination = s->expire_url;
 240                 cv[1].destination = s->expire_mimetypes;
 241
 242                 p->config_storage[i] = s;
 243
 244                 if (0 != config_insert_values_global(srv, config->value, cv, i == 0 ? T_CONFIG_SCOPE_SERVER : T_CONFIG_SCOPE_CONNECTION)) {
 245                         return HANDLER_ERROR;
 246                 }
 247
 248                 if (!array_is_kvstring(s->expire_url)) {
 249                         log_error_write(srv, __FILE__, __LINE__, "s",
 250                                         "unexpected value for expire.url; expected list of \"urlpath\" => \"expiration\"");
 251                         return HANDLER_ERROR;
 252                 }
 253
 254                 for (k = 0; k < s->expire_url->used; k++) {
 255                         data_string *ds = (data_string *)s->expire_url->data[k];
 256
 257                         /* parse lines */
 258                         if (-1 == mod_expire_get_offset(srv, p, ds->value, NULL)) {
 259                                 log_error_write(srv, __FILE__, __LINE__, "sb",
 260                                                 "parsing expire.url failed:", ds->value);
 261                                 return HANDLER_ERROR;
 262                         }
 263                 }
 264
 265                 if (!array_is_kvstring(s->expire_mimetypes)) {
 266                         log_error_write(srv, __FILE__, __LINE__, "s",
 267                                         "unexpected value for expire.mimetypes; expected list of \"mimetype\" => \"expiration\"");
 268                         return HANDLER_ERROR;
 269                 }
 270
 271                 for (k = 0; k < s->expire_mimetypes->used; k++) {
 272                         data_string *ds = (data_string *)s->expire_mimetypes->data[k];
 273                         size_t klen = buffer_string_length(ds->key);
 274
 275                         /*(omit trailing '*', if present, from prefix match)*/
 276                         /*(not usually a good idea to modify array keys
 277                          * since doing so might break array_get_element_klen() search,
 278                          * but array use in this module only walks array)*/
 279                         if (klen && ds->key->ptr[klen-1] == '*') buffer_string_set_length(ds->key, klen-1);
 280
 281                         /* parse lines */
 282                         if (-1 == mod_expire_get_offset(srv, p, ds->value, NULL)) {
 283                                 log_error_write(srv, __FILE__, __LINE__, "sb",
 284                                                 "parsing expire.mimetypes failed:", ds->value);
 285                                 return HANDLER_ERROR;
 286                         }
 287                 }
 288         }
 289
 290
 291         return HANDLER_GO_ON;
 292 }
 293
 294 #define PATCH(x) \
 295         p->conf.x = s->x;
 296 static int mod_expire_patch_connection(server *srv, connection *con, plugin_data *p) {
 297         size_t i, j;
 298         plugin_config *s = p->config_storage[0];
 299
 300         PATCH(expire_url);
 301         PATCH(expire_mimetypes);
 302
 303         /* skip the first, the global context */
 304         for (i = 1; i < srv->config_context->used; i++) {
 305                 data_config *dc = (data_config *)srv->config_context->data[i];
 306                 s = p->config_storage[i];
 307
 308                 /* condition didn't match */
 309                 if (!config_check_cond(srv, con, dc)) continue;
 310
 311                 /* merge config */
 312                 for (j = 0; j < dc->value->used; j++) {
 313                         data_unset *du = dc->value->data[j];
 314
 315                         if (buffer_is_equal_string(du->key, CONST_STR_LEN("expire.url"))) {
 316                                 PATCH(expire_url);
 317                         } else if (buffer_is_equal_string(du->key, CONST_STR_LEN("expire.mimetypes"))) {
 318                                 PATCH(expire_mimetypes);
 319                         }
 320                 }
 321         }
 322
 323         return 0;
 324 }
 325 #undef PATCH
 326
 327 CONNECTION_FUNC(mod_expire_handler) {
 328         plugin_data *p = p_d;
 329         buffer *vb;
 330         data_string *ds;
 331
 332         /* Add caching headers only to http_status 200 OK or 206 Partial Content */
 333         if (con->http_status != 200 && con->http_status != 206) return HANDLER_GO_ON;
 334         /* Add caching headers only to GET or HEAD requests */
 335         if (   con->request.http_method != HTTP_METHOD_GET
 336             && con->request.http_method != HTTP_METHOD_HEAD) return HANDLER_GO_ON;
 337         /* Add caching headers only if not already present */
 338         vb = http_header_response_get(con, HTTP_HEADER_CACHE_CONTROL, CONST_STR_LEN("Cache-Control"));
 339         if (NULL != vb) return HANDLER_GO_ON;
 340
 341         if (buffer_is_empty(con->uri.path)) return HANDLER_GO_ON;
 342
 343         mod_expire_patch_connection(srv, con, p);
 344
 345         /* check expire.url */
 346         ds = (data_string *)array_match_key_prefix(p->conf.expire_url, con->uri.path);
 347         if (NULL != ds) {
 348                 vb = ds->value;
 349         }
 350         else {
 351                 /* check expire.mimetypes (if no match with expire.url) */
 352                 vb = http_header_response_get(con, HTTP_HEADER_CONTENT_TYPE, CONST_STR_LEN("Content-Type"));
 353                 ds = (NULL != vb)
 354                    ? (data_string *)array_match_key_prefix(p->conf.expire_mimetypes, vb)
 355                    : (data_string *)array_get_element_klen(p->conf.expire_mimetypes, CONST_STR_LEN(""));
 356                 if (NULL == ds) return HANDLER_GO_ON;
 357                 vb = ds->value;
 358         }
 359
 360         if (NULL != vb) {
 361                         time_t ts, expires;
 362                         stat_cache_entry *sce = NULL;
 363
 364                         switch(mod_expire_get_offset(srv, p, vb, &ts)) {
 365                         case 0:
 366                                 /* access */
 367                                 expires = (ts + srv->cur_ts);
 368                                 break;
 369                         case 1:
 370                                 /* modification */
 371
 372                                 /* if stat fails => sce == NULL, ignore return value */
 373                                 (void) stat_cache_get_entry(srv, con, con->physical.path, &sce);
 374
 375                                 /* can't set modification based expire header if
 376                                  * mtime is not available
 377                                  */
 378                                 if (NULL == sce) return HANDLER_GO_ON;
 379
 380                                 expires = (ts + sce->st.st_mtime);
 381                                 break;
 382                         default:
 383                                 /* -1 is handled at parse-time */
 384                                 return HANDLER_ERROR;
 385                         }
 386
 387                         /* expires should be at least srv->cur_ts */
 388                         if (expires < srv->cur_ts) expires = srv->cur_ts;
 389
 390                         buffer_clear(p->expire_tstmp);
 391                         buffer_append_strftime(p->expire_tstmp, "%a, %d %b %Y %H:%M:%S GMT", gmtime(&(expires)));
 392
 393                         /* HTTP/1.0 */
 394                         http_header_response_set(con, HTTP_HEADER_OTHER, CONST_STR_LEN("Expires"), CONST_BUF_LEN(p->expire_tstmp));
 395
 396                         /* HTTP/1.1 */
 397                         buffer_copy_string_len(p->expire_tstmp, CONST_STR_LEN("max-age="));
 398                         buffer_append_int(p->expire_tstmp, expires - srv->cur_ts); /* as expires >= srv->cur_ts the difference is >= 0 */
 399
 400                         http_header_response_set(con, HTTP_HEADER_CACHE_CONTROL, CONST_STR_LEN("Cache-Control"), CONST_BUF_LEN(p->expire_tstmp));
 401
 402                         return HANDLER_GO_ON;
 403         }
 404
 405         /* not found */
 406         return HANDLER_GO_ON;
 407 }
 408
 409 /* this function is called at dlopen() time and inits the callbacks */
 410
 411 int mod_expire_plugin_init(plugin *p);
 412 int mod_expire_plugin_init(plugin *p) {
 413         p->version     = LIGHTTPD_VERSION_ID;
 414         p->name        = buffer_init_string("expire");
 415
 416         p->init        = mod_expire_init;
 417         p->handle_response_start = mod_expire_handler;
 418         p->set_defaults  = mod_expire_set_defaults;
 419         p->cleanup     = mod_expire_free;
 420
 421         p->data        = NULL;
 422
 423         return 0;
 424 }