src/mod_expire.c

   1 #include "first.h"
   2
   3 #include "base.h"
   4 #include "log.h"
   5 #include "buffer.h"
   6 #include "response.h"
   7
   8 #include "plugin.h"
   9 #include "stat_cache.h"
  10
  11 #include <ctype.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <time.h>
  15
  16 /**
  17  * this is a expire module for a lighttpd
  18  *
  19  * set 'Expires:' HTTP Headers on demand
  20  */
  21
  22
  23
  24 /* plugin config for all request/connections */
  25
  26 typedef struct {
  27         array *expire_url;
  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                         free(s);
  72                 }
  73                 free(p->config_storage);
  74         }
  75
  76         free(p);
  77
  78         return HANDLER_GO_ON;
  79 }
  80
  81 static int mod_expire_get_offset(server *srv, plugin_data *p, buffer *expire, time_t *offset) {
  82         char *ts;
  83         int type = -1;
  84         time_t retts = 0;
  85
  86         UNUSED(p);
  87
  88         /*
  89          * parse
  90          *
  91          * '(access|now|modification) [plus] {<num> <type>}*'
  92          *
  93          * e.g. 'access 1 years'
  94          */
  95
  96         if (buffer_string_is_empty(expire)) {
  97                 log_error_write(srv, __FILE__, __LINE__, "s",
  98                                 "empty:");
  99                 return -1;
 100         }
 101
 102         ts = expire->ptr;
 103
 104         if (0 == strncmp(ts, "access ", 7)) {
 105                 type  = 0;
 106                 ts   += 7;
 107         } else if (0 == strncmp(ts, "now ", 4)) {
 108                 type  = 0;
 109                 ts   += 4;
 110         } else if (0 == strncmp(ts, "modification ", 13)) {
 111                 type  = 1;
 112                 ts   += 13;
 113         } else {
 114                 /* invalid type-prefix */
 115                 log_error_write(srv, __FILE__, __LINE__, "ss",
 116                                 "invalid <base>:", ts);
 117                 return -1;
 118         }
 119
 120         if (0 == strncmp(ts, "plus ", 5)) {
 121                 /* skip the optional plus */
 122                 ts   += 5;
 123         }
 124
 125         /* the rest is just <number> (years|months|weeks|days|hours|minutes|seconds) */
 126         while (1) {
 127                 char *space, *err;
 128                 int num;
 129
 130                 if (NULL == (space = strchr(ts, ' '))) {
 131                         log_error_write(srv, __FILE__, __LINE__, "ss",
 132                                         "missing space after <num>:", ts);
 133                         return -1;
 134                 }
 135
 136                 num = strtol(ts, &err, 10);
 137                 if (*err != ' ') {
 138                         log_error_write(srv, __FILE__, __LINE__, "ss",
 139                                         "missing <type> after <num>:", ts);
 140                         return -1;
 141                 }
 142
 143                 ts = space + 1;
 144
 145                 if (NULL != (space = strchr(ts, ' '))) {
 146                         int slen;
 147                         /* */
 148
 149                         slen = space - ts;
 150
 151                         if (slen == 5 &&
 152                             0 == strncmp(ts, "years", slen)) {
 153                                 num *= 60 * 60 * 24 * 30 * 12;
 154                         } else if (slen == 6 &&
 155                                    0 == strncmp(ts, "months", slen)) {
 156                                 num *= 60 * 60 * 24 * 30;
 157                         } else if (slen == 5 &&
 158                                    0 == strncmp(ts, "weeks", slen)) {
 159                                 num *= 60 * 60 * 24 * 7;
 160                         } else if (slen == 4 &&
 161                                    0 == strncmp(ts, "days", slen)) {
 162                                 num *= 60 * 60 * 24;
 163                         } else if (slen == 5 &&
 164                                    0 == strncmp(ts, "hours", slen)) {
 165                                 num *= 60 * 60;
 166                         } else if (slen == 7 &&
 167                                    0 == strncmp(ts, "minutes", slen)) {
 168                                 num *= 60;
 169                         } else if (slen == 7 &&
 170                                    0 == strncmp(ts, "seconds", slen)) {
 171                                 num *= 1;
 172                         } else {
 173                                 log_error_write(srv, __FILE__, __LINE__, "ss",
 174                                                 "unknown type:", ts);
 175                                 return -1;
 176                         }
 177
 178                         retts += num;
 179
 180                         ts = space + 1;
 181                 } else {
 182                         if (0 == strcmp(ts, "years")) {
 183                                 num *= 60 * 60 * 24 * 30 * 12;
 184                         } else if (0 == strcmp(ts, "months")) {
 185                                 num *= 60 * 60 * 24 * 30;
 186                         } else if (0 == strcmp(ts, "weeks")) {
 187                                 num *= 60 * 60 * 24 * 7;
 188                         } else if (0 == strcmp(ts, "days")) {
 189                                 num *= 60 * 60 * 24;
 190                         } else if (0 == strcmp(ts, "hours")) {
 191                                 num *= 60 * 60;
 192                         } else if (0 == strcmp(ts, "minutes")) {
 193                                 num *= 60;
 194                         } else if (0 == strcmp(ts, "seconds")) {
 195                                 num *= 1;
 196                         } else {
 197                                 log_error_write(srv, __FILE__, __LINE__, "ss",
 198                                                 "unknown type:", ts);
 199                                 return -1;
 200                         }
 201
 202                         retts += num;
 203
 204                         break;
 205                 }
 206         }
 207
 208         if (offset != NULL) *offset = retts;
 209
 210         return type;
 211 }
 212
 213
 214 /* handle plugin config and check values */
 215
 216 SETDEFAULTS_FUNC(mod_expire_set_defaults) {
 217         plugin_data *p = p_d;
 218         size_t i = 0, k;
 219
 220         config_values_t cv[] = {
 221                 { "expire.url",                 NULL, T_CONFIG_ARRAY, T_CONFIG_SCOPE_CONNECTION },       /* 0 */
 222                 { NULL,                         NULL, T_CONFIG_UNSET, T_CONFIG_SCOPE_UNSET }
 223         };
 224
 225         if (!p) return HANDLER_ERROR;
 226
 227         p->config_storage = calloc(1, srv->config_context->used * sizeof(plugin_config *));
 228
 229         for (i = 0; i < srv->config_context->used; i++) {
 230                 data_config const* config = (data_config const*)srv->config_context->data[i];
 231                 plugin_config *s;
 232
 233                 s = calloc(1, sizeof(plugin_config));
 234                 s->expire_url    = array_init();
 235
 236                 cv[0].destination = s->expire_url;
 237
 238                 p->config_storage[i] = s;
 239
 240                 if (0 != config_insert_values_global(srv, config->value, cv, i == 0 ? T_CONFIG_SCOPE_SERVER : T_CONFIG_SCOPE_CONNECTION)) {
 241                         return HANDLER_ERROR;
 242                 }
 243
 244                 for (k = 0; k < s->expire_url->used; k++) {
 245                         data_string *ds = (data_string *)s->expire_url->data[k];
 246
 247                         /* parse lines */
 248                         if (-1 == mod_expire_get_offset(srv, p, ds->value, NULL)) {
 249                                 log_error_write(srv, __FILE__, __LINE__, "sb",
 250                                                 "parsing expire.url failed:", ds->value);
 251                                 return HANDLER_ERROR;
 252                         }
 253                 }
 254         }
 255
 256
 257         return HANDLER_GO_ON;
 258 }
 259
 260 #define PATCH(x) \
 261         p->conf.x = s->x;
 262 static int mod_expire_patch_connection(server *srv, connection *con, plugin_data *p) {
 263         size_t i, j;
 264         plugin_config *s = p->config_storage[0];
 265
 266         PATCH(expire_url);
 267
 268         /* skip the first, the global context */
 269         for (i = 1; i < srv->config_context->used; i++) {
 270                 data_config *dc = (data_config *)srv->config_context->data[i];
 271                 s = p->config_storage[i];
 272
 273                 /* condition didn't match */
 274                 if (!config_check_cond(srv, con, dc)) continue;
 275
 276                 /* merge config */
 277                 for (j = 0; j < dc->value->used; j++) {
 278                         data_unset *du = dc->value->data[j];
 279
 280                         if (buffer_is_equal_string(du->key, CONST_STR_LEN("expire.url"))) {
 281                                 PATCH(expire_url);
 282                         }
 283                 }
 284         }
 285
 286         return 0;
 287 }
 288 #undef PATCH
 289
 290 URIHANDLER_FUNC(mod_expire_path_handler) {
 291         plugin_data *p = p_d;
 292         int s_len;
 293         size_t k;
 294
 295         if (buffer_is_empty(con->uri.path)) return HANDLER_GO_ON;
 296
 297         mod_expire_patch_connection(srv, con, p);
 298
 299         s_len = buffer_string_length(con->uri.path);
 300
 301         for (k = 0; k < p->conf.expire_url->used; k++) {
 302                 data_string *ds = (data_string *)p->conf.expire_url->data[k];
 303                 int ct_len = buffer_string_length(ds->key);
 304
 305                 if (ct_len > s_len) continue;
 306                 if (buffer_is_empty(ds->key)) continue;
 307
 308                 if (0 == strncmp(con->uri.path->ptr, ds->key->ptr, ct_len)) {
 309                         time_t ts, expires;
 310                         stat_cache_entry *sce = NULL;
 311
 312                         /* if stat fails => sce == NULL, ignore return value */
 313                         (void) stat_cache_get_entry(srv, con, con->physical.path, &sce);
 314
 315                         switch(mod_expire_get_offset(srv, p, ds->value, &ts)) {
 316                         case 0:
 317                                 /* access */
 318                                 expires = (ts + srv->cur_ts);
 319                                 break;
 320                         case 1:
 321                                 /* modification */
 322
 323                                 /* can't set modification based expire header if
 324                                  * mtime is not available
 325                                  */
 326                                 if (NULL == sce) return HANDLER_GO_ON;
 327
 328                                 expires = (ts + sce->st.st_mtime);
 329                                 break;
 330                         default:
 331                                 /* -1 is handled at parse-time */
 332                                 return HANDLER_ERROR;
 333                         }
 334
 335                         /* expires should be at least srv->cur_ts */
 336                         if (expires < srv->cur_ts) expires = srv->cur_ts;
 337
 338                         buffer_string_prepare_copy(p->expire_tstmp, 255);
 339                         buffer_append_strftime(p->expire_tstmp, "%a, %d %b %Y %H:%M:%S GMT", gmtime(&(expires)));
 340
 341                         /* HTTP/1.0 */
 342                         response_header_overwrite(srv, con, CONST_STR_LEN("Expires"), CONST_BUF_LEN(p->expire_tstmp));
 343
 344                         /* HTTP/1.1 */
 345                         buffer_copy_string_len(p->expire_tstmp, CONST_STR_LEN("max-age="));
 346                         buffer_append_int(p->expire_tstmp, expires - srv->cur_ts); /* as expires >= srv->cur_ts the difference is >= 0 */
 347
 348                         response_header_append(srv, con, CONST_STR_LEN("Cache-Control"), CONST_BUF_LEN(p->expire_tstmp));
 349
 350                         return HANDLER_GO_ON;
 351                 }
 352         }
 353
 354         /* not found */
 355         return HANDLER_GO_ON;
 356 }
 357
 358 /* this function is called at dlopen() time and inits the callbacks */
 359
 360 int mod_expire_plugin_init(plugin *p);
 361 int mod_expire_plugin_init(plugin *p) {
 362         p->version     = LIGHTTPD_VERSION_ID;
 363         p->name        = buffer_init_string("expire");
 364
 365         p->init        = mod_expire_init;
 366         p->handle_subrequest_start = mod_expire_path_handler;
 367         p->set_defaults  = mod_expire_set_defaults;
 368         p->cleanup     = mod_expire_free;
 369
 370         p->data        = NULL;
 371
 372         return 0;
 373 }