1 #include "first.h" 2 3 #include <stdlib.h> 4 #include <string.h> 5 6 #include "sys-crypto-md.h" /* USE_LIB_CRYPTO */ 7 8 #include "base.h" 9 #include "plugin.h" 10 #include "http_auth.h" 11 #include "http_header.h" 12 #include "log.h" 13 #include "safe_memclear.h" 14 #include "splaytree.h" 15 16 /** 17 * auth framework 18 */ 19 20 typedef struct { 21 splay_tree *sptree; /* data in nodes of tree are (http_auth_cache_entry *)*/ 22 time_t max_age; 23 } http_auth_cache; 24 25 typedef struct { 26 const http_auth_backend_t *auth_backend; 27 const array *auth_require; 28 http_auth_cache *auth_cache; 29 unsigned int auth_extern_authn; 30 } plugin_config; 31 32 typedef struct { 33 PLUGIN_DATA; 34 plugin_config defaults; 35 plugin_config conf; 36 } plugin_data; 37 38 typedef struct { 39 const struct http_auth_require_t *require; 40 time_t ctime; 41 int dalgo; 42 uint32_t dlen; 43 uint32_t ulen; 44 char *username; 45 char *pwdigest; 46 } http_auth_cache_entry; 47 48 static http_auth_cache_entry * 49 http_auth_cache_entry_init (const struct http_auth_require_t * const require, const int dalgo, const char *username, const uint32_t ulen, const char *pw, const uint32_t pwlen) 50 { 51 /*(similar to buffer_copy_string_len() for each element, 52 * but allocate exact lengths in single chunk of memory 53 * for cache to avoid wasting space and for memory locality)*/ 54 /* http_auth_require_t is stored instead of copying realm 55 *(store pointer to http_auth_require_t, which is persistent 56 * and will be different for each realm + permissions combo)*/ 57 http_auth_cache_entry * const ae = 58 malloc(sizeof(http_auth_cache_entry) + ulen + pwlen); 59 force_assert(ae); 60 ae->require = require; 61 ae->ctime = log_epoch_secs; 62 ae->dalgo = dalgo; 63 ae->ulen = ulen; 64 ae->dlen = pwlen; 65 ae->username = (char *)(ae + 1); 66 ae->pwdigest = ae->username + ulen; 67 memcpy(ae->username, username, ulen); 68 memcpy(ae->pwdigest, pw, pwlen); 69 return ae; 70 } 71 72 static void 73 http_auth_cache_entry_free (void *data) 74 { 75 http_auth_cache_entry * const ae = data; 76 safe_memclear(ae->pwdigest, ae->dlen); 77 free(ae); 78 } 79 80 static void 81 http_auth_cache_free (http_auth_cache *ac) 82 { 83 splay_tree *sptree = ac->sptree; 84 while (sptree) { 85 http_auth_cache_entry_free(sptree->data); 86 sptree = splaytree_delete(sptree, sptree->key); 87 } 88 free(ac); 89 } 90 91 static http_auth_cache * 92 http_auth_cache_init (const array *opts) 93 { 94 http_auth_cache *ac = malloc(sizeof(http_auth_cache)); 95 force_assert(ac); 96 ac->sptree = NULL; 97 ac->max_age = 600; /* 10 mins */ 98 for (uint32_t i = 0, used = opts->used; i < used; ++i) { 99 data_string *ds = (data_string *)opts->data[i]; 100 if (buffer_is_equal_string(&ds->key, CONST_STR_LEN("max-age"))) { 101 if (ds->type == TYPE_STRING) 102 ac->max_age = (time_t)strtol(ds->value.ptr, NULL, 10); 103 else if (ds->type == TYPE_INTEGER) 104 ac->max_age = (time_t)((data_integer *)ds)->value; 105 } 106 } 107 return ac; 108 } 109 110 static int 111 http_auth_cache_hash (const struct http_auth_require_t * const require, const char *username, const uint32_t ulen) 112 { 113 uint32_t h = /*(hash pointer value, which includes realm and permissions)*/ 114 djbhash((char *)(intptr_t)require, sizeof(intptr_t), DJBHASH_INIT); 115 h = djbhash(username, ulen, h); 116 /* strip highest bit of hash value for splaytree (see splaytree_djbhash())*/ 117 return (int32_t)(h & ~(((uint32_t)1) << 31)); 118 } 119 120 static http_auth_cache_entry * 121 http_auth_cache_query (splay_tree ** const sptree, const int ndx) 122 { 123 *sptree = splaytree_splay(*sptree, ndx); 124 return (*sptree && (*sptree)->key == ndx) ? (*sptree)->data : NULL; 125 } 126 127 static void 128 http_auth_cache_insert (splay_tree ** const sptree, const int ndx, void * const data, void(data_free_fn)(void *)) 129 { 130 /*(not necessary to re-splay (with current usage) since single-threaded 131 * and splaytree has not been modified since http_auth_cache_query())*/ 132 /* *sptree = splaytree_splay(*sptree, ndx); */ 133 if (NULL == *sptree || (*sptree)->key != ndx) 134 *sptree = splaytree_insert(*sptree, ndx, data); 135 else { /* collision; replace old entry */ 136 data_free_fn((*sptree)->data); 137 (*sptree)->data = data; 138 } 139 } 140 141 /* walk though cache, collect expired ids, and remove them in a second loop */ 142 static void 143 mod_auth_tag_old_entries (splay_tree * const t, int * const keys, int * const ndx, const time_t max_age, const time_t cur_ts) 144 { 145 if (*ndx == 8192) return; /*(must match num array entries in keys[])*/ 146 if (t->left) 147 mod_auth_tag_old_entries(t->left, keys, ndx, max_age, cur_ts); 148 if (t->right) 149 mod_auth_tag_old_entries(t->right, keys, ndx, max_age, cur_ts); 150 if (*ndx == 8192) return; /*(must match num array entries in keys[])*/ 151 152 const http_auth_cache_entry * const ae = t->data; 153 if (cur_ts - ae->ctime > max_age) 154 keys[(*ndx)++] = t->key; 155 } 156 157 __attribute_noinline__ 158 static void 159 mod_auth_periodic_cleanup(splay_tree **sptree_ptr, const time_t max_age, const time_t cur_ts) 160 { 161 splay_tree *sptree = *sptree_ptr; 162 int max_ndx, i; 163 int keys[8192]; /* 32k size on stack */ 164 do { 165 if (!sptree) break; 166 max_ndx = 0; 167 mod_auth_tag_old_entries(sptree, keys, &max_ndx, max_age, cur_ts); 168 for (i = 0; i < max_ndx; ++i) { 169 int ndx = keys[i]; 170 sptree = splaytree_splay(sptree, ndx); 171 if (sptree && sptree->key == ndx) { 172 http_auth_cache_entry_free(sptree->data); 173 sptree = splaytree_delete(sptree, ndx); 174 } 175 } 176 } while (max_ndx == sizeof(keys)/sizeof(int)); 177 *sptree_ptr = sptree; 178 } 179 180 TRIGGER_FUNC(mod_auth_periodic) 181 { 182 const plugin_data * const p = p_d; 183 const time_t cur_ts = log_epoch_secs; 184 if (cur_ts & 0x7) return HANDLER_GO_ON; /*(continue once each 8 sec)*/ 185 UNUSED(srv); 186 187 /* future: might construct array of (http_auth_cache *) at startup 188 * to avoid the need to search for them here */ 189 for (int i = 0, used = p->nconfig; i < used; ++i) { 190 const config_plugin_value_t *cpv = p->cvlist + p->cvlist[i].v.u2[0]; 191 for (; cpv->k_id != -1; ++cpv) { 192 if (cpv->k_id != 3) continue; /* k_id == 3 for auth.cache */ 193 if (cpv->vtype != T_CONFIG_LOCAL) continue; 194 http_auth_cache *ac = cpv->v.v; 195 mod_auth_periodic_cleanup(&ac->sptree, ac->max_age, cur_ts); 196 } 197 } 198 199 return HANDLER_GO_ON; 200 } 201 202 203 204 205 static handler_t mod_auth_check_basic(request_st *r, void *p_d, const struct http_auth_require_t *require, const struct http_auth_backend_t *backend); 206 static handler_t mod_auth_check_digest(request_st *r, void *p_d, const struct http_auth_require_t *require, const struct http_auth_backend_t *backend); 207 static handler_t mod_auth_check_extern(request_st *r, void *p_d, const struct http_auth_require_t *require, const struct http_auth_backend_t *backend); 208 209 INIT_FUNC(mod_auth_init) { 210 static http_auth_scheme_t http_auth_scheme_basic = { "basic", mod_auth_check_basic, NULL }; 211 static http_auth_scheme_t http_auth_scheme_digest = { "digest", mod_auth_check_digest, NULL }; 212 static const http_auth_scheme_t http_auth_scheme_extern = { "extern", mod_auth_check_extern, NULL }; 213 plugin_data *p = calloc(1, sizeof(*p)); 214 force_assert(p); 215 216 /* register http_auth_scheme_* */ 217 http_auth_scheme_basic.p_d = p; 218 http_auth_scheme_set(&http_auth_scheme_basic); 219 http_auth_scheme_digest.p_d = p; 220 http_auth_scheme_set(&http_auth_scheme_digest); 221 http_auth_scheme_set(&http_auth_scheme_extern); 222 223 return p; 224 } 225 226 FREE_FUNC(mod_auth_free) { 227 plugin_data * const p = p_d; 228 if (NULL == p->cvlist) return; 229 /* (init i to 0 if global context; to 1 to skip empty global context) */ 230 for (int i = !p->cvlist[0].v.u2[1], used = p->nconfig; i < used; ++i) { 231 config_plugin_value_t *cpv = p->cvlist + p->cvlist[i].v.u2[0]; 232 for (; -1 != cpv->k_id; ++cpv) { 233 if (cpv->vtype != T_CONFIG_LOCAL || NULL == cpv->v.v) continue; 234 switch (cpv->k_id) { 235 case 1: /* auth.require */ 236 array_free(cpv->v.v); 237 break; 238 case 3: /* auth.cache */ 239 http_auth_cache_free(cpv->v.v); 240 break; 241 default: 242 break; 243 } 244 } 245 } 246 } 247 248 /* data type for mod_auth structured data 249 * (parsed from auth.require array of strings) */ 250 typedef struct { 251 DATA_UNSET; 252 http_auth_require_t *require; 253 } data_auth; 254 255 static void data_auth_free(data_unset *d) 256 { 257 data_auth * const dauth = (data_auth *)d; 258 free(dauth->key.ptr); 259 http_auth_require_free(dauth->require); 260 free(dauth); 261 } 262 263 static data_auth *data_auth_init(void) 264 { 265 static const struct data_methods fn = { 266 NULL, /* copy must not be called on this data */ 267 data_auth_free, 268 NULL, /* insert_dup must not be called on this data */ 269 NULL /* print must not be called on this data */ 270 }; 271 data_auth * const dauth = calloc(1, sizeof(*dauth)); 272 force_assert(NULL != dauth); 273 dauth->type = TYPE_OTHER; 274 dauth->fn = &fn; 275 276 dauth->require = http_auth_require_init(); 277 278 return dauth; 279 } 280 281 static int mod_auth_algorithm_parse(http_auth_info_t *ai, const char *s) { 282 size_t len; 283 if (NULL == s) { 284 ai->dalgo = HTTP_AUTH_DIGEST_MD5; 285 ai->dlen = HTTP_AUTH_DIGEST_MD5_BINLEN; 286 return 1; 287 } 288 289 len = strlen(s); 290 if (len > 5 291 && (s[len-5] ) == '-' 292 && (s[len-4] | 0x20) == 's' 293 && (s[len-3] | 0x20) == 'e' 294 && (s[len-2] | 0x20) == 's' 295 && (s[len-1] | 0x20) == 's') { 296 ai->dalgo = HTTP_AUTH_DIGEST_SESS; 297 len -= 5; 298 } 299 else { 300 ai->dalgo = HTTP_AUTH_DIGEST_NONE; 301 } 302 303 if (3 == len 304 && 'm' == (s[0] | 0x20) 305 && 'd' == (s[1] | 0x20) 306 && '5' == (s[2] )) { 307 ai->dalgo |= HTTP_AUTH_DIGEST_MD5; 308 ai->dlen = HTTP_AUTH_DIGEST_MD5_BINLEN; 309 return 1; 310 } 311 #ifdef USE_LIB_CRYPTO 312 else if (len >= 7 313 && 's' == (s[0] | 0x20) 314 && 'h' == (s[1] | 0x20) 315 && 'a' == (s[2] | 0x20) 316 && '-' == (s[3] )) { 317 if (len == 7 && s[4] == '2' && s[5] == '5' && s[6] == '6') { 318 ai->dalgo |= HTTP_AUTH_DIGEST_SHA256; 319 ai->dlen = HTTP_AUTH_DIGEST_SHA256_BINLEN; 320 return 1; 321 } 322 #ifdef USE_LIB_CRYPTO_SHA512_256 323 if (len == 11 && 0 == memcmp(s+4, "512-256", 7)) { 324 ai->dalgo |= HTTP_AUTH_DIGEST_SHA512_256; 325 ai->dlen = HTTP_AUTH_DIGEST_SHA512_256_BINLEN; 326 return 1; 327 } 328 #endif 329 } 330 #endif 331 return 0; /*(error)*/ 332 } 333 334 static int mod_auth_algorithms_parse(int *algorithm, buffer *algos) { 335 for (char *s = algos->ptr, *p; s; s = p ? p+1 : NULL) { 336 http_auth_info_t ai; 337 int rc; 338 p = strchr(s, '|'); 339 if (p) *p = '\0'; 340 rc = mod_auth_algorithm_parse(&ai, s); 341 if (p) *p = '|'; 342 if (!rc) return 0; 343 *algorithm |= ai.dalgo; 344 } 345 return 1; 346 } 347 348 static int mod_auth_require_parse (http_auth_require_t * const require, const buffer *b, log_error_st *errh) 349 { 350 /* user=name1|user=name2|group=name3|host=name4 */ 351 352 const char *str = b->ptr; 353 const char *p; 354 355 if (buffer_is_equal_string(b, CONST_STR_LEN("valid-user"))) { 356 require->valid_user = 1; 357 return 1; /* success */ 358 } 359 360 do { 361 const char *eq; 362 size_t len; 363 p = strchr(str, '|'); 364 len = NULL != p ? (size_t)(p - str) : strlen(str); 365 eq = memchr(str, '=', len); 366 if (NULL == eq) { 367 log_error(errh, __FILE__, __LINE__, 368 "error parsing auth.require 'require' field: missing '=' " 369 "(expecting \"valid-user\" or \"user=a|user=b|group=g|host=h\"). " 370 "error value: %s error near: %s", b->ptr, str); 371 return 0; 372 } 373 if (eq[1] == '|' || eq[1] == '\0') { 374 log_error(errh, __FILE__, __LINE__, 375 "error parsing auth.require 'require' field: " 376 "missing token after '=' " 377 "(expecting \"valid-user\" or \"user=a|user=b|group=g|host=h\"). " 378 "error value: %s error near: %s", b->ptr, str); 379 return 0; 380 } 381 382 switch ((int)(eq - str)) { 383 case 4: 384 if (0 == memcmp(str, CONST_STR_LEN("user"))) { 385 /*("user=" is 5)*/ 386 array_set_key_value(&require->user, str+5, len-5, CONST_STR_LEN("")); 387 continue; 388 } 389 else if (0 == memcmp(str, CONST_STR_LEN("host"))) { 390 /*("host=" is 5)*/ 391 array_set_key_value(&require->host, str+5, len-5, CONST_STR_LEN("")); 392 log_error(errh, __FILE__, __LINE__, 393 "warning parsing auth.require 'require' field: " 394 "'host' not implemented; field value: %s", b->ptr); 395 continue; 396 } 397 break; /* to error */ 398 case 5: 399 if (0 == memcmp(str, CONST_STR_LEN("group"))) { 400 /*("group=" is 6)*/ 401 array_set_key_value(&require->group, str+6, len-6, CONST_STR_LEN("")); 402 #if 0/*(supported by mod_authn_ldap, but not all other backends)*/ 403 log_error(errh, __FILE__, __LINE__, 404 "warning parsing auth.require 'require' field: " 405 "'group' not implemented; field value: %s", b->ptr); 406 #endif 407 continue; 408 } 409 break; /* to error */ 410 case 10: 411 if (0 == memcmp(str, CONST_STR_LEN("valid-user"))) { 412 log_error(errh, __FILE__, __LINE__, 413 "error parsing auth.require 'require' field: " 414 "valid user can not be combined with other require rules " 415 "(expecting \"valid-user\" or " 416 "\"user=a|user=b|group=g|host=h\"). error value: %s", b->ptr); 417 return 0; 418 } 419 break; /* to error */ 420 default: 421 break; /* to error */ 422 } 423 424 log_error(errh, __FILE__, __LINE__, 425 "error parsing auth.require 'require' field: " 426 "invalid/unsupported token " 427 "(expecting \"valid-user\" or \"user=a|user=b|group=g|host=h\"). " 428 "error value: %s error near: %s", b->ptr, str); 429 return 0; 430 431 } while (p && *((str = p+1))); 432 433 return 1; /* success */ 434 } 435 436 static handler_t mod_auth_require_parse_array(const array *value, array * const auth_require, log_error_st *errh) 437 { 438 for (uint32_t n = 0; n < value->used; ++n) { 439 size_t m; 440 data_array *da_file = (data_array *)value->data[n]; 441 const buffer *method = NULL, *realm = NULL, *require = NULL; 442 const buffer *nonce_secret = NULL; 443 const http_auth_scheme_t *auth_scheme; 444 buffer *algos = NULL; 445 int algorithm = HTTP_AUTH_DIGEST_SESS; 446 447 if (!array_is_kvstring(&da_file->value)) { 448 log_error(errh, __FILE__, __LINE__, 449 "unexpected value for auth.require; expected " 450 "auth.require = ( \"urlpath\" => ( \"option\" => \"value\" ) )"); 451 452 return HANDLER_ERROR; 453 } 454 455 for (m = 0; m < da_file->value.used; m++) { 456 if (da_file->value.data[m]->type == TYPE_STRING) { 457 data_string *ds = (data_string *)da_file->value.data[m]; 458 if (buffer_is_equal_string(&ds->key, CONST_STR_LEN("method"))) { 459 method = &ds->value; 460 } else if (buffer_is_equal_string(&ds->key, CONST_STR_LEN("realm"))) { 461 realm = &ds->value; 462 } else if (buffer_is_equal_string(&ds->key, CONST_STR_LEN("require"))) { 463 require = &ds->value; 464 } else if (buffer_is_equal_string(&ds->key, CONST_STR_LEN("algorithm"))) { 465 algos = &ds->value; 466 } else if (buffer_is_equal_string(&ds->key, CONST_STR_LEN("nonce_secret")) 467 || buffer_is_equal_string(&ds->key, CONST_STR_LEN("nonce-secret"))) { 468 nonce_secret = &ds->value; 469 } else { 470 log_error(errh, __FILE__, __LINE__, 471 "the field is unknown in: " 472 "auth.require = ( \"...\" => ( ..., -> \"%s\" <- => \"...\" ) )", 473 da_file->value.data[m]->key.ptr); 474 475 return HANDLER_ERROR; 476 } 477 } else { 478 log_error(errh, __FILE__, __LINE__, 479 "a string was expected for: " 480 "auth.require = ( \"...\" => ( ..., -> \"%s\" <- => \"...\" ) )", 481 da_file->value.data[m]->key.ptr); 482 483 return HANDLER_ERROR; 484 } 485 } 486 487 if (buffer_string_is_empty(method)) { 488 log_error(errh, __FILE__, __LINE__, 489 "the method field is missing or blank in: " 490 "auth.require = ( \"...\" => ( ..., \"method\" => \"...\" ) )"); 491 return HANDLER_ERROR; 492 } else { 493 auth_scheme = http_auth_scheme_get(method); 494 if (NULL == auth_scheme) { 495 log_error(errh, __FILE__, __LINE__, 496 "unknown method %s (e.g. \"basic\", \"digest\" or \"extern\") in " 497 "auth.require = ( \"...\" => ( ..., \"method\" => \"...\") )", method->ptr); 498 return HANDLER_ERROR; 499 } 500 } 501 502 if (buffer_is_empty(realm)) { 503 log_error(errh, __FILE__, __LINE__, 504 "the realm field is missing in: " 505 "auth.require = ( \"...\" => ( ..., \"realm\" => \"...\" ) )"); 506 return HANDLER_ERROR; 507 } 508 509 if (buffer_string_is_empty(require)) { 510 log_error(errh, __FILE__, __LINE__, 511 "the require field is missing or blank in: " 512 "auth.require = ( \"...\" => ( ..., \"require\" => \"...\" ) )"); 513 return HANDLER_ERROR; 514 } 515 516 if (buffer_string_is_empty(algos)) { 517 algorithm |= HTTP_AUTH_DIGEST_MD5; 518 } else if (!mod_auth_algorithms_parse(&algorithm, algos)) { 519 log_error(errh, __FILE__, __LINE__, 520 "invalid algorithm in: " 521 "auth.require = ( \"...\" => ( ..., \"algorithm\" => \"...\" ) )"); 522 return HANDLER_ERROR; 523 } 524 525 if (require) { /*(always true at this point)*/ 526 data_auth * const dauth = data_auth_init(); 527 buffer_copy_buffer(&dauth->key, &da_file->key); 528 dauth->require->scheme = auth_scheme; 529 dauth->require->algorithm = algorithm; 530 dauth->require->realm = realm; 531 dauth->require->nonce_secret = nonce_secret; /*(NULL is ok)*/ 532 if (!mod_auth_require_parse(dauth->require, require, errh)) { 533 dauth->fn->free((data_unset *)dauth); 534 return HANDLER_ERROR; 535 } 536 array_insert_unique(auth_require, (data_unset *)dauth); 537 } 538 } 539 540 return HANDLER_GO_ON; 541 } 542 543 static void mod_auth_merge_config_cpv(plugin_config * const pconf, const config_plugin_value_t * const cpv) { 544 switch (cpv->k_id) { /* index into static config_plugin_keys_t cpk[] */ 545 case 0: /* auth.backend */ 546 if (cpv->vtype == T_CONFIG_LOCAL) 547 pconf->auth_backend = cpv->v.v; 548 break; 549 case 1: /* auth.require */ 550 if (cpv->vtype == T_CONFIG_LOCAL) 551 pconf->auth_require = cpv->v.v; 552 break; 553 case 2: /* auth.extern-authn */ 554 pconf->auth_extern_authn = cpv->v.u; 555 break; 556 case 3: /* auth.cache */ 557 if (cpv->vtype == T_CONFIG_LOCAL) 558 pconf->auth_cache = cpv->v.v; 559 break; 560 default:/* should not happen */ 561 return; 562 } 563 } 564 565 static void mod_auth_merge_config(plugin_config * const pconf, const config_plugin_value_t *cpv) { 566 do { 567 mod_auth_merge_config_cpv(pconf, cpv); 568 } while ((++cpv)->k_id != -1); 569 } 570 571 static void mod_auth_patch_config(request_st * const r, plugin_data * const p) { 572 p->conf = p->defaults; /* copy small struct instead of memcpy() */ 573 /*memcpy(&p->conf, &p->defaults, sizeof(plugin_config));*/ 574 for (int i = 1, used = p->nconfig; i < used; ++i) { 575 if (config_check_cond(r, (uint32_t)p->cvlist[i].k_id)) 576 mod_auth_merge_config(&p->conf, p->cvlist + p->cvlist[i].v.u2[0]); 577 } 578 } 579 580 SETDEFAULTS_FUNC(mod_auth_set_defaults) { 581 static const config_plugin_keys_t cpk[] = { 582 { CONST_STR_LEN("auth.backend"), 583 T_CONFIG_STRING, 584 T_CONFIG_SCOPE_CONNECTION } 585 ,{ CONST_STR_LEN("auth.require"), 586 T_CONFIG_ARRAY_KVARRAY, 587 T_CONFIG_SCOPE_CONNECTION } 588 ,{ CONST_STR_LEN("auth.extern-authn"), 589 T_CONFIG_BOOL, 590 T_CONFIG_SCOPE_CONNECTION } 591 ,{ CONST_STR_LEN("auth.cache"), 592 T_CONFIG_ARRAY, 593 T_CONFIG_SCOPE_CONNECTION } 594 ,{ NULL, 0, 595 T_CONFIG_UNSET, 596 T_CONFIG_SCOPE_UNSET } 597 }; 598 599 plugin_data * const p = p_d; 600 if (!config_plugin_values_init(srv, p, cpk, "mod_auth")) 601 return HANDLER_ERROR; 602 603 /* process and validate config directives 604 * (init i to 0 if global context; to 1 to skip empty global context) */ 605 for (int i = !p->cvlist[0].v.u2[1]; i < p->nconfig; ++i) { 606 config_plugin_value_t *cpv = p->cvlist + p->cvlist[i].v.u2[0]; 607 for (; -1 != cpv->k_id; ++cpv) { 608 switch (cpv->k_id) { 609 case 0: /* auth.backend */ 610 if (!buffer_string_is_empty(cpv->v.b)) { 611 const http_auth_backend_t * const auth_backend = 612 http_auth_backend_get(cpv->v.b); 613 if (NULL == auth_backend) { 614 log_error(srv->errh, __FILE__, __LINE__, 615 "auth.backend not supported: %s", cpv->v.b->ptr); 616 return HANDLER_ERROR; 617 } 618 *(const http_auth_backend_t **)&cpv->v.v = auth_backend; 619 cpv->vtype = T_CONFIG_LOCAL; 620 } 621 break; 622 case 1: /* auth.require */ 623 { 624 array * const a = array_init(4); 625 if (HANDLER_GO_ON != 626 mod_auth_require_parse_array(cpv->v.a, a, srv->errh)) { 627 array_free(a); 628 return HANDLER_ERROR; 629 } 630 cpv->v.a = a; 631 cpv->vtype = T_CONFIG_LOCAL; 632 } 633 break; 634 case 2: /* auth.extern-authn */ 635 break; 636 case 3: /* auth.cache */ 637 cpv->v.v = http_auth_cache_init(cpv->v.a); 638 cpv->vtype = T_CONFIG_LOCAL; 639 break; 640 default:/* should not happen */ 641 break; 642 } 643 } 644 } 645 646 /* initialize p->defaults from global config context */ 647 if (p->nconfig > 0 && p->cvlist->v.u2[1]) { 648 const config_plugin_value_t *cpv = p->cvlist + p->cvlist->v.u2[0]; 649 if (-1 != cpv->k_id) 650 mod_auth_merge_config(&p->defaults, cpv); 651 } 652 653 return HANDLER_GO_ON; 654 } 655 656 static handler_t mod_auth_uri_handler(request_st * const r, void *p_d) { 657 plugin_data *p = p_d; 658 data_auth *dauth; 659 660 mod_auth_patch_config(r, p); 661 662 if (p->conf.auth_require == NULL) return HANDLER_GO_ON; 663 664 /* search auth directives for first prefix match against URL path */ 665 /* if we have a case-insensitive FS we have to lower-case the URI here too */ 666 dauth = (!r->conf.force_lowercase_filenames) 667 ? (data_auth *)array_match_key_prefix(p->conf.auth_require, &r->uri.path) 668 : (data_auth *)array_match_key_prefix_nc(p->conf.auth_require, &r->uri.path); 669 if (NULL == dauth) return HANDLER_GO_ON; 670 671 { 672 const http_auth_scheme_t * const scheme = dauth->require->scheme; 673 if (p->conf.auth_extern_authn) { 674 const buffer *vb = http_header_env_get(r, CONST_STR_LEN("REMOTE_USER")); 675 if (NULL != vb && http_auth_match_rules(dauth->require, vb->ptr, NULL, NULL)) { 676 return HANDLER_GO_ON; 677 } 678 } 679 return scheme->checkfn(r, scheme->p_d, dauth->require, p->conf.auth_backend); 680 } 681 } 682 683 684 int mod_auth_plugin_init(plugin *p); 685 int mod_auth_plugin_init(plugin *p) { 686 p->version = LIGHTTPD_VERSION_ID; 687 p->name = "auth"; 688 p->init = mod_auth_init; 689 p->set_defaults = mod_auth_set_defaults; 690 p->handle_trigger = mod_auth_periodic; 691 p->handle_uri_clean = mod_auth_uri_handler; 692 p->cleanup = mod_auth_free; 693 694 return 0; 695 } 696 697 698 699 700 /* 701 * auth schemes (basic, digest, extern) 702 * 703 * (could be in separate file from mod_auth.c as long as registration occurs) 704 */ 705 706 #include "sys-crypto-md.h" 707 #include "base64.h" 708 #include "rand.h" 709 #include "http_header.h" 710 711 __attribute_cold__ 712 static handler_t mod_auth_send_400_bad_request(request_st * const r) { 713 714 /* a field was missing or invalid */ 715 r->http_status = 400; /* Bad Request */ 716 r->handler_module = NULL; 717 718 return HANDLER_FINISHED; 719 } 720 721 static handler_t mod_auth_send_401_unauthorized_basic(request_st * const r, const buffer * const realm) { 722 r->http_status = 401; 723 r->handler_module = NULL; 724 725 buffer * const tb = r->tmp_buf; 726 buffer_copy_string_len(tb, CONST_STR_LEN("Basic realm=\"")); 727 buffer_append_string_buffer(tb, realm); 728 buffer_append_string_len(tb, CONST_STR_LEN("\", charset=\"UTF-8\"")); 729 730 http_header_response_set(r, HTTP_HEADER_OTHER, CONST_STR_LEN("WWW-Authenticate"), CONST_BUF_LEN(tb)); 731 732 return HANDLER_FINISHED; 733 } 734 735 static handler_t mod_auth_check_basic(request_st * const r, void *p_d, const struct http_auth_require_t * const require, const struct http_auth_backend_t * const backend) { 736 const buffer *b = http_header_request_get(r, HTTP_HEADER_AUTHORIZATION, CONST_STR_LEN("Authorization")); 737 buffer *username; 738 char *pw; 739 handler_t rc = HANDLER_UNSET; 740 741 if (NULL == backend) { 742 log_error(r->conf.errh, __FILE__, __LINE__, "auth.backend not configured for %s", r->uri.path.ptr); 743 r->http_status = 500; 744 r->handler_module = NULL; 745 return HANDLER_FINISHED; 746 } 747 748 if (NULL == b) { 749 return mod_auth_send_401_unauthorized_basic(r, require->realm); 750 } 751 752 if (!buffer_eq_icase_ssn(b->ptr, CONST_STR_LEN("Basic "))) { 753 return mod_auth_send_401_unauthorized_basic(r, require->realm); 754 } 755 #ifdef __COVERITY__ 756 if (buffer_string_length(b) < sizeof("Basic ")-1) { 757 return mod_auth_send_400_bad_request(r); 758 } 759 #endif 760 761 username = buffer_init(); 762 763 /* coverity[overflow_sink : FALSE] */ 764 if (!buffer_append_base64_decode(username, b->ptr+sizeof("Basic ")-1, buffer_string_length(b)-(sizeof("Basic ")-1), BASE64_STANDARD)) { 765 log_error(r->conf.errh, __FILE__, __LINE__, "decoding base64-string failed %s", b->ptr+sizeof("Basic ")-1); 766 767 buffer_free(username); 768 return mod_auth_send_400_bad_request(r); 769 } 770 771 /* r2 == user:password */ 772 if (NULL == (pw = strchr(username->ptr, ':'))) { 773 log_error(r->conf.errh, __FILE__, __LINE__, "missing ':' in %s", username->ptr); 774 775 buffer_free(username); 776 return mod_auth_send_400_bad_request(r); 777 } 778 779 uint32_t pwlen = buffer_string_length(username); 780 buffer_string_set_length(username, pw - username->ptr); 781 pw++; 782 pwlen -= (pw - username->ptr); 783 784 plugin_data * const p = p_d; 785 splay_tree ** sptree = p->conf.auth_cache 786 ? &p->conf.auth_cache->sptree 787 : NULL; 788 http_auth_cache_entry *ae = NULL; 789 int ndx = -1; 790 if (sptree) { 791 ndx = http_auth_cache_hash(require, CONST_BUF_LEN(username)); 792 ae = http_auth_cache_query(sptree, ndx); 793 if (ae && ae->require == require 794 && buffer_is_equal_string(username, ae->username, ae->ulen)) 795 rc = http_auth_const_time_memeq_pad(ae->pwdigest, ae->dlen, 796 pw, pwlen) 797 ? HANDLER_GO_ON 798 : HANDLER_ERROR; 799 else /*(not found or hash collision)*/ 800 ae = NULL; 801 } 802 803 if (NULL == ae) /* (HANDLER_UNSET == rc) */ 804 rc = backend->basic(r, backend->p_d, require, username, pw); 805 806 switch (rc) { 807 case HANDLER_GO_ON: 808 http_auth_setenv(r, CONST_BUF_LEN(username), CONST_STR_LEN("Basic")); 809 if (sptree && NULL == ae) { /*(cache (new) successful result)*/ 810 ae = http_auth_cache_entry_init(require, 0, CONST_BUF_LEN(username), 811 pw, pwlen); 812 http_auth_cache_insert(sptree, ndx, ae, http_auth_cache_entry_free); 813 } 814 break; 815 case HANDLER_WAIT_FOR_EVENT: 816 case HANDLER_FINISHED: 817 break; 818 case HANDLER_ERROR: 819 default: 820 log_error(r->conf.errh, __FILE__, __LINE__, 821 "password doesn't match for %s username: %s IP: %s", 822 r->uri.path.ptr, username->ptr, r->con->dst_addr_buf->ptr); 823 r->keep_alive = 0; /*(disable keep-alive if bad password)*/ 824 rc = HANDLER_UNSET; 825 break; 826 } 827 828 buffer_free(username); 829 return (HANDLER_UNSET != rc) ? rc : mod_auth_send_401_unauthorized_basic(r, require->realm); 830 } 831 832 833 #ifdef USE_LIB_CRYPTO 834 835 static void mod_auth_digest_mutate_sha256(http_auth_info_t *ai, const char *m, const char *uri, const char *nonce, const char *cnonce, const char *nc, const char *qop) { 836 SHA256_CTX ctx; 837 char a1[HTTP_AUTH_DIGEST_SHA256_BINLEN*2+1]; 838 char a2[HTTP_AUTH_DIGEST_SHA256_BINLEN*2+1]; 839 840 if (ai->dalgo & HTTP_AUTH_DIGEST_SESS) { 841 SHA256_Init(&ctx); 842 li_tohex(a1, sizeof(a1), (const char *)ai->digest, ai->dlen); 843 SHA256_Update(&ctx, (unsigned char *)a1, sizeof(a1)-1); 844 SHA256_Update(&ctx, CONST_STR_LEN(":")); 845 SHA256_Update(&ctx, (unsigned char *)nonce, strlen(nonce)); 846 SHA256_Update(&ctx, CONST_STR_LEN(":")); 847 SHA256_Update(&ctx, (unsigned char *)cnonce, strlen(cnonce)); 848 SHA256_Final(ai->digest, &ctx); 849 } 850 851 li_tohex(a1, sizeof(a1), (const char *)ai->digest, ai->dlen); 852 853 /* calculate H(A2) */ 854 SHA256_Init(&ctx); 855 SHA256_Update(&ctx, (unsigned char *)m, strlen(m)); 856 SHA256_Update(&ctx, CONST_STR_LEN(":")); 857 SHA256_Update(&ctx, (unsigned char *)uri, strlen(uri)); 858 #if 0 859 /* qop=auth-int not supported, already checked in caller */ 860 if (qop && buffer_eq_icase_ss(qop, strlen(qop), CONST_STR_LEN("auth-int"))){ 861 SHA256_Update(&ctx, CONST_STR_LEN(":")); 862 SHA256_Update(&ctx, (unsigned char *) [body checksum], ai->dlen*2); 863 } 864 #endif 865 SHA256_Final(ai->digest, &ctx); 866 li_tohex(a2, sizeof(a2), (const char *)ai->digest, ai->dlen); 867 868 /* calculate response */ 869 SHA256_Init(&ctx); 870 SHA256_Update(&ctx, (unsigned char *)a1, sizeof(a1)-1); 871 SHA256_Update(&ctx, CONST_STR_LEN(":")); 872 SHA256_Update(&ctx, (unsigned char *)nonce, strlen(nonce)); 873 SHA256_Update(&ctx, CONST_STR_LEN(":")); 874 if (qop && *qop) { 875 SHA256_Update(&ctx, (unsigned char *)nc, strlen(nc)); 876 SHA256_Update(&ctx, CONST_STR_LEN(":")); 877 SHA256_Update(&ctx, (unsigned char *)cnonce, strlen(cnonce)); 878 SHA256_Update(&ctx, CONST_STR_LEN(":")); 879 SHA256_Update(&ctx, (unsigned char *)qop, strlen(qop)); 880 SHA256_Update(&ctx, CONST_STR_LEN(":")); 881 } 882 SHA256_Update(&ctx, (unsigned char *)a2, sizeof(a2)-1); 883 SHA256_Final(ai->digest, &ctx); 884 } 885 886 static void mod_auth_digest_nonce_sha256(buffer *b, time_t cur_ts, int rnd, const buffer *secret) { 887 SHA256_CTX ctx; 888 size_t len; 889 unsigned char h[HTTP_AUTH_DIGEST_SHA256_BINLEN]; 890 char hh[HTTP_AUTH_DIGEST_SHA256_BINLEN*2+1]; 891 force_assert(sizeof(hh) >= LI_ITOSTRING_LENGTH); 892 SHA256_Init(&ctx); 893 len = li_itostrn(hh, sizeof(hh), cur_ts); 894 SHA256_Update(&ctx, (unsigned char *)hh, len); 895 len = li_itostrn(hh, sizeof(hh), rnd); 896 SHA256_Update(&ctx, (unsigned char *)hh, len); 897 if (secret) { 898 len = buffer_string_length(secret); 899 SHA256_Update(&ctx, (unsigned char *)secret->ptr, len); 900 } 901 SHA256_Final(h, &ctx); 902 li_tohex(hh, sizeof(hh), (const char *)h, sizeof(h)); 903 buffer_append_string_len(b, hh, sizeof(hh)-1); 904 } 905 906 #ifdef USE_LIB_CRYPTO_SHA512_256 907 908 static void mod_auth_digest_mutate_sha512_256(http_auth_info_t *ai, const char *m, const char *uri, const char *nonce, const char *cnonce, const char *nc, const char *qop) { 909 SHA512_CTX ctx; 910 char a1[HTTP_AUTH_DIGEST_SHA512_256_BINLEN*2+1]; 911 char a2[HTTP_AUTH_DIGEST_SHA512_256_BINLEN*2+1]; 912 913 if (ai->dalgo & HTTP_AUTH_DIGEST_SESS) { 914 SHA512_256_Init(&ctx); 915 li_tohex(a1, sizeof(a1), (const char *)ai->digest, ai->dlen); 916 SHA512_256_Update(&ctx, (unsigned char *)a1, sizeof(a1)-1); 917 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 918 SHA512_256_Update(&ctx, (unsigned char *)nonce, strlen(nonce)); 919 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 920 SHA512_256_Update(&ctx, (unsigned char *)cnonce, strlen(cnonce)); 921 SHA512_256_Final(ai->digest, &ctx); 922 } 923 924 li_tohex(a1, sizeof(a1), (const char *)ai->digest, ai->dlen); 925 926 /* calculate H(A2) */ 927 SHA512_256_Init(&ctx); 928 SHA512_256_Update(&ctx, (unsigned char *)m, strlen(m)); 929 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 930 SHA512_256_Update(&ctx, (unsigned char *)uri, strlen(uri)); 931 #if 0 932 /* qop=auth-int not supported, already checked in caller */ 933 if (qop && buffer_eq_icase_ss(qop, strlen(qop), CONST_STR_LEN("auth-int"))){ 934 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 935 SHA512_256_Update(&ctx, (unsigned char *)[body checksum], ai->dlen*2); 936 } 937 #endif 938 SHA512_256_Final(ai->digest, &ctx); 939 li_tohex(a2, sizeof(a2), (const char *)ai->digest, ai->dlen); 940 941 /* calculate response */ 942 SHA512_256_Init(&ctx); 943 SHA512_256_Update(&ctx, (unsigned char *)a1, sizeof(a1)-1); 944 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 945 SHA512_256_Update(&ctx, (unsigned char *)nonce, strlen(nonce)); 946 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 947 if (qop && *qop) { 948 SHA512_256_Update(&ctx, (unsigned char *)nc, strlen(nc)); 949 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 950 SHA512_256_Update(&ctx, (unsigned char *)cnonce, strlen(cnonce)); 951 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 952 SHA512_256_Update(&ctx, (unsigned char *)qop, strlen(qop)); 953 SHA512_256_Update(&ctx, CONST_STR_LEN(":")); 954 } 955 SHA512_256_Update(&ctx, (unsigned char *)a2, sizeof(a2)-1); 956 SHA512_256_Final(ai->digest, &ctx); 957 } 958 959 static void mod_auth_digest_nonce_sha512_256(buffer *b, time_t cur_ts, int rnd, const buffer *secret) { 960 SHA512_CTX ctx; 961 size_t len; 962 unsigned char h[HTTP_AUTH_DIGEST_SHA512_256_BINLEN]; 963 char hh[HTTP_AUTH_DIGEST_SHA512_256_BINLEN*2+1]; 964 force_assert(sizeof(hh) >= LI_ITOSTRING_LENGTH); 965 SHA512_256_Init(&ctx); 966 len = li_itostrn(hh, sizeof(hh), cur_ts); 967 SHA512_256_Update(&ctx, (unsigned char *)hh, len); 968 len = li_itostrn(hh, sizeof(hh), rnd); 969 SHA512_256_Update(&ctx, (unsigned char *)hh, len); 970 if (secret) { 971 len = buffer_string_length(secret); 972 SHA512_256_Update(&ctx, (unsigned char *)secret->ptr, len); 973 } 974 SHA512_256_Final(h, &ctx); 975 li_tohex(hh, sizeof(hh), (const char *)h, sizeof(h)); 976 buffer_append_string_len(b, hh, sizeof(hh)-1); 977 } 978 979 #endif /* USE_LIB_CRYPTO_SHA512_256 */ 980 981 #endif /* USE_LIB_CRYPTO */ 982 983 static void mod_auth_digest_mutate_md5(http_auth_info_t *ai, const char *m, const char *uri, const char *nonce, const char *cnonce, const char *nc, const char *qop) { 984 li_MD5_CTX ctx; 985 char a1[HTTP_AUTH_DIGEST_MD5_BINLEN*2+1]; 986 char a2[HTTP_AUTH_DIGEST_MD5_BINLEN*2+1]; 987 988 if (ai->dalgo & HTTP_AUTH_DIGEST_SESS) { 989 li_MD5_Init(&ctx); 990 /* http://www.rfc-editor.org/errata_search.php?rfc=2617 991 * Errata ID: 1649 */ 992 li_tohex(a1, sizeof(a1), (const char *)ai->digest, ai->dlen); 993 li_MD5_Update(&ctx, (unsigned char *)a1, sizeof(a1)-1); 994 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 995 li_MD5_Update(&ctx, (unsigned char *)nonce, strlen(nonce)); 996 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 997 li_MD5_Update(&ctx, (unsigned char *)cnonce, strlen(cnonce)); 998 li_MD5_Final(ai->digest, &ctx); 999 } 1000 1001 li_tohex(a1, sizeof(a1), (const char *)ai->digest, ai->dlen); 1002 1003 /* calculate H(A2) */ 1004 li_MD5_Init(&ctx); 1005 li_MD5_Update(&ctx, (unsigned char *)m, strlen(m)); 1006 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 1007 li_MD5_Update(&ctx, (unsigned char *)uri, strlen(uri)); 1008 #if 0 1009 /* qop=auth-int not supported, already checked in caller */ 1010 if (qop && buffer_eq_icase_ss(qop, strlen(qop), CONST_STR_LEN("auth-int"))){ 1011 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 1012 li_MD5_Update(&ctx, (unsigned char *) [body checksum], ai->dlen*2); 1013 } 1014 #endif 1015 li_MD5_Final(ai->digest, &ctx); 1016 li_tohex(a2, sizeof(a2), (const char *)ai->digest, ai->dlen); 1017 1018 /* calculate response */ 1019 li_MD5_Init(&ctx); 1020 li_MD5_Update(&ctx, (unsigned char *)a1, sizeof(a1)-1); 1021 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 1022 li_MD5_Update(&ctx, (unsigned char *)nonce, strlen(nonce)); 1023 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 1024 if (qop && *qop) { 1025 li_MD5_Update(&ctx, (unsigned char *)nc, strlen(nc)); 1026 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 1027 li_MD5_Update(&ctx, (unsigned char *)cnonce, strlen(cnonce)); 1028 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 1029 li_MD5_Update(&ctx, (unsigned char *)qop, strlen(qop)); 1030 li_MD5_Update(&ctx, CONST_STR_LEN(":")); 1031 } 1032 li_MD5_Update(&ctx, (unsigned char *)a2, sizeof(a2)-1); 1033 li_MD5_Final(ai->digest, &ctx); 1034 } 1035 1036 static void mod_auth_digest_nonce_md5(buffer *b, time_t cur_ts, int rnd, const buffer *secret) { 1037 li_MD5_CTX ctx; 1038 size_t len; 1039 unsigned char h[HTTP_AUTH_DIGEST_MD5_BINLEN]; 1040 char hh[HTTP_AUTH_DIGEST_MD5_BINLEN*2+1]; 1041 force_assert(sizeof(hh) >= LI_ITOSTRING_LENGTH); 1042 li_MD5_Init(&ctx); 1043 len = li_itostrn(hh, sizeof(hh), cur_ts); 1044 li_MD5_Update(&ctx, (unsigned char *)hh, len); 1045 len = li_itostrn(hh, sizeof(hh), rnd); 1046 li_MD5_Update(&ctx, (unsigned char *)hh, len); 1047 if (secret) { 1048 len = buffer_string_length(secret); 1049 li_MD5_Update(&ctx, (unsigned char *)secret->ptr, len); 1050 } 1051 li_MD5_Final(h, &ctx); 1052 li_tohex(hh, sizeof(hh), (const char *)h, sizeof(h)); 1053 buffer_append_string_len(b, hh, sizeof(hh)-1); 1054 } 1055 1056 static void mod_auth_digest_mutate(http_auth_info_t *ai, const char *m, const char *uri, const char *nonce, const char *cnonce, const char *nc, const char *qop) { 1057 if (ai->dalgo & HTTP_AUTH_DIGEST_MD5) 1058 mod_auth_digest_mutate_md5(ai, m, uri, nonce, cnonce, nc, qop); 1059 #ifdef USE_LIB_CRYPTO 1060 else if (ai->dalgo & HTTP_AUTH_DIGEST_SHA256) 1061 mod_auth_digest_mutate_sha256(ai, m, uri, nonce, cnonce, nc, qop); 1062 #ifdef USE_LIB_CRYPTO_SHA512_256 1063 else if (ai->dalgo & HTTP_AUTH_DIGEST_SHA512_256) 1064 mod_auth_digest_mutate_sha512_256(ai, m, uri, nonce, cnonce, nc, qop); 1065 #endif 1066 #endif 1067 } 1068 1069 static void mod_auth_append_nonce(buffer *b, time_t cur_ts, const struct http_auth_require_t *require, int dalgo, int *rndptr) { 1070 buffer_append_uint_hex(b, (uintmax_t)cur_ts); 1071 buffer_append_string_len(b, CONST_STR_LEN(":")); 1072 const buffer * const nonce_secret = require->nonce_secret; 1073 int rnd; 1074 if (NULL == nonce_secret) 1075 rnd = rndptr ? *rndptr : li_rand_pseudo(); 1076 else { /*(do not directly expose random number generator single value)*/ 1077 rndptr 1078 ? (void)(rnd = *rndptr) 1079 : li_rand_pseudo_bytes((unsigned char *)&rnd, sizeof(rnd)); 1080 buffer_append_uint_hex(b, (uintmax_t)rnd); 1081 buffer_append_string_len(b, CONST_STR_LEN(":")); 1082 } 1083 switch (dalgo) { 1084 #ifdef USE_LIB_CRYPTO 1085 #ifdef USE_LIB_CRYPTO_SHA512_256 1086 case HTTP_AUTH_DIGEST_SHA512_256: 1087 mod_auth_digest_nonce_sha512_256(b, cur_ts, rnd, nonce_secret); 1088 break; 1089 #endif 1090 case HTTP_AUTH_DIGEST_SHA256: 1091 mod_auth_digest_nonce_sha256(b, cur_ts, rnd, nonce_secret); 1092 break; 1093 #endif 1094 /*case HTTP_AUTH_DIGEST_MD5:*/ 1095 default: 1096 mod_auth_digest_nonce_md5(b, cur_ts, rnd, nonce_secret); 1097 break; 1098 } 1099 } 1100 1101 static void mod_auth_digest_www_authenticate(buffer *b, time_t cur_ts, const struct http_auth_require_t *require, int nonce_stale) { 1102 int algos = nonce_stale ? nonce_stale : require->algorithm; 1103 int n = 0; 1104 int algoid[3]; 1105 unsigned int algolen[3]; 1106 const char *algoname[3]; 1107 #ifdef USE_LIB_CRYPTO 1108 #ifdef USE_LIB_CRYPTO_SHA512_256 1109 if (algos & HTTP_AUTH_DIGEST_SHA512_256) { 1110 algoid[n] = HTTP_AUTH_DIGEST_SHA512_256; 1111 algoname[n] = "SHA-512-256"; 1112 algolen[n] = sizeof("SHA-512-256")-1; 1113 ++n; 1114 } 1115 #endif 1116 if (algos & HTTP_AUTH_DIGEST_SHA256) { 1117 algoid[n] = HTTP_AUTH_DIGEST_SHA256; 1118 algoname[n] = "SHA-256"; 1119 algolen[n] = sizeof("SHA-256")-1; 1120 ++n; 1121 } 1122 #endif 1123 if (algos & HTTP_AUTH_DIGEST_MD5) { 1124 algoid[n] = HTTP_AUTH_DIGEST_MD5; 1125 algoname[n] = "MD5"; 1126 algolen[n] = sizeof("MD5")-1; 1127 ++n; 1128 } 1129 1130 buffer_clear(b); 1131 for (int i = 0; i < n; ++i) { 1132 if (i > 0) { 1133 buffer_append_string_len(b,CONST_STR_LEN("\r\nWWW-Authenticate: ")); 1134 } 1135 buffer_append_string_len(b, CONST_STR_LEN("Digest realm=\"")); 1136 buffer_append_string_buffer(b, require->realm); 1137 buffer_append_string_len(b, CONST_STR_LEN("\", charset=\"UTF-8\", algorithm=")); 1138 buffer_append_string_len(b, algoname[i], algolen[i]); 1139 buffer_append_string_len(b, CONST_STR_LEN(", nonce=\"")); 1140 mod_auth_append_nonce(b, cur_ts, require, algoid[i], NULL); 1141 buffer_append_string_len(b, CONST_STR_LEN("\", qop=\"auth\"")); 1142 if (nonce_stale) { 1143 buffer_append_string_len(b, CONST_STR_LEN(", stale=true")); 1144 } 1145 } 1146 } 1147 1148 static void mod_auth_digest_authentication_info(buffer *b, time_t cur_ts, const struct http_auth_require_t *require, int dalgo) { 1149 buffer_clear(b); 1150 buffer_append_string_len(b, CONST_STR_LEN("nextnonce=\"")); 1151 mod_auth_append_nonce(b, cur_ts, require, dalgo, NULL); 1152 buffer_append_string_len(b, CONST_STR_LEN("\"")); 1153 } 1154 1155 typedef struct { 1156 const char *key; 1157 int key_len; 1158 char **ptr; 1159 } digest_kv; 1160 1161 static handler_t mod_auth_send_401_unauthorized_digest(request_st *r, const struct http_auth_require_t *require, int nonce_stale); 1162 1163 static handler_t mod_auth_check_digest(request_st * const r, void *p_d, const struct http_auth_require_t * const require, const struct http_auth_backend_t * const backend) { 1164 const buffer *vb = http_header_request_get(r, HTTP_HEADER_AUTHORIZATION, CONST_STR_LEN("Authorization")); 1165 1166 char *username = NULL; 1167 char *realm = NULL; 1168 char *nonce = NULL; 1169 char *uri = NULL; 1170 char *algorithm = NULL; 1171 char *qop = NULL; 1172 char *cnonce = NULL; 1173 char *nc = NULL; 1174 char *respons = NULL; 1175 1176 char *e, *c; 1177 int i; 1178 buffer *b; 1179 http_auth_info_t ai; 1180 unsigned char rdigest[HTTP_AUTH_DIGEST_SHA256_BINLEN]; 1181 1182 1183 /* init pointers */ 1184 #define S(x) \ 1185 x, sizeof(x)-1, NULL 1186 digest_kv dkv[10] = { 1187 { S("username=") }, 1188 { S("realm=") }, 1189 { S("nonce=") }, 1190 { S("uri=") }, 1191 { S("algorithm=") }, 1192 { S("qop=") }, 1193 { S("cnonce=") }, 1194 { S("nc=") }, 1195 { S("response=") }, 1196 1197 { NULL, 0, NULL } 1198 }; 1199 #undef S 1200 1201 dkv[0].ptr = &username; 1202 dkv[1].ptr = &realm; 1203 dkv[2].ptr = &nonce; 1204 dkv[3].ptr = &uri; 1205 dkv[4].ptr = &algorithm; 1206 dkv[5].ptr = &qop; 1207 dkv[6].ptr = &cnonce; 1208 dkv[7].ptr = &nc; 1209 dkv[8].ptr = &respons; 1210 1211 if (NULL == backend) { 1212 log_error(r->conf.errh, __FILE__, __LINE__, 1213 "auth.backend not configured for %s", r->uri.path.ptr); 1214 r->http_status = 500; 1215 r->handler_module = NULL; 1216 return HANDLER_FINISHED; 1217 } 1218 1219 if (NULL == vb) { 1220 return mod_auth_send_401_unauthorized_digest(r, require, 0); 1221 } 1222 1223 if (!buffer_eq_icase_ssn(vb->ptr, CONST_STR_LEN("Digest "))) { 1224 return mod_auth_send_401_unauthorized_digest(r, require, 0); 1225 } else { 1226 size_t n = buffer_string_length(vb); 1227 #ifdef __COVERITY__ 1228 if (n < sizeof("Digest ")-1) { 1229 return mod_auth_send_400_bad_request(r); 1230 } 1231 #endif 1232 n -= (sizeof("Digest ")-1); 1233 b = buffer_init(); 1234 buffer_copy_string_len(b,vb->ptr+sizeof("Digest ")-1,n); 1235 } 1236 1237 /* parse credentials from client */ 1238 for (c = b->ptr; *c; c++) { 1239 /* skip whitespaces */ 1240 while (*c == ' ' || *c == '\t') c++; 1241 if (!*c) break; 1242 1243 for (i = 0; dkv[i].key; i++) { 1244 if ((0 == strncmp(c, dkv[i].key, dkv[i].key_len))) { 1245 if ((c[dkv[i].key_len] == '"') && 1246 (NULL != (e = strchr(c + dkv[i].key_len + 1, '"')))) { 1247 /* value with "..." */ 1248 *(dkv[i].ptr) = c + dkv[i].key_len + 1; 1249 c = e; 1250 1251 *e = '\0'; 1252 } else if (NULL != (e = strchr(c + dkv[i].key_len, ','))) { 1253 /* value without "...", terminated by ',' */ 1254 *(dkv[i].ptr) = c + dkv[i].key_len; 1255 c = e; 1256 1257 *e = '\0'; 1258 } else { 1259 /* value without "...", terminated by EOL */ 1260 *(dkv[i].ptr) = c + dkv[i].key_len; 1261 c += strlen(c) - 1; 1262 } 1263 break; 1264 } 1265 } 1266 } 1267 1268 /* check if everything is transmitted */ 1269 if (!username || 1270 !realm || 1271 !nonce || 1272 !uri || 1273 (qop && (!nc || !cnonce)) || 1274 !respons ) { 1275 /* missing field */ 1276 1277 log_error(r->conf.errh, __FILE__, __LINE__, 1278 "digest: missing field"); 1279 1280 buffer_free(b); 1281 return mod_auth_send_400_bad_request(r); 1282 } 1283 1284 ai.username = username; 1285 ai.ulen = strlen(username); 1286 ai.realm = realm; 1287 ai.rlen = strlen(realm); 1288 1289 if (!buffer_is_equal_string(require->realm, ai.realm, ai.rlen)) { 1290 log_error(r->conf.errh, __FILE__, __LINE__, 1291 "digest: realm mismatch"); 1292 buffer_free(b); 1293 return mod_auth_send_401_unauthorized_digest(r, require, 0); 1294 } 1295 1296 if (!mod_auth_algorithm_parse(&ai, algorithm) 1297 || !(require->algorithm & ai.dalgo & ~HTTP_AUTH_DIGEST_SESS)) { 1298 log_error(r->conf.errh, __FILE__, __LINE__, 1299 "digest: (%s): invalid", algorithm); 1300 buffer_free(b); 1301 return mod_auth_send_400_bad_request(r); 1302 } 1303 1304 /** 1305 * protect the md5-sess against missing cnonce and nonce 1306 */ 1307 if ((ai.dalgo & HTTP_AUTH_DIGEST_SESS) && (!nonce || !cnonce)) { 1308 log_error(r->conf.errh, __FILE__, __LINE__, 1309 "digest: (%s): missing field", algorithm); 1310 1311 buffer_free(b); 1312 return mod_auth_send_400_bad_request(r); 1313 } 1314 1315 { 1316 size_t resplen = strlen(respons); 1317 if (0 != http_auth_digest_hex2bin(respons, resplen, 1318 rdigest, sizeof(rdigest)) 1319 || resplen != (ai.dlen << 1)) { 1320 log_error(r->conf.errh, __FILE__, __LINE__, 1321 "digest: (%s): invalid format", respons); 1322 buffer_free(b); 1323 return mod_auth_send_400_bad_request(r); 1324 } 1325 } 1326 1327 if (qop && buffer_eq_icase_ss(qop, strlen(qop), CONST_STR_LEN("auth-int"))){ 1328 log_error(r->conf.errh, __FILE__, __LINE__, 1329 "digest: qop=auth-int not supported"); 1330 1331 buffer_free(b); 1332 return mod_auth_send_400_bad_request(r); 1333 } 1334 1335 /* detect if attacker is attempting to reuse valid digest for one uri 1336 * on a different request uri. Might also happen if intermediate proxy 1337 * altered client request line. (Altered request would not result in 1338 * the same digest as that calculated by the client.) 1339 * Internal redirects such as with mod_rewrite will modify request uri. 1340 * Reauthentication is done to detect crossing auth realms, but this 1341 * uri validation step is bypassed. r->target_orig is 1342 * original request-target sent in client request. */ 1343 { 1344 const size_t ulen = strlen(uri); 1345 if (!buffer_is_equal_string(&r->target_orig, uri, ulen)) { 1346 log_error(r->conf.errh, __FILE__, __LINE__, 1347 "digest: auth failed: uri mismatch (%s != %s), IP: %s", 1348 r->target_orig.ptr, uri, r->con->dst_addr_buf->ptr); 1349 buffer_free(b); 1350 return mod_auth_send_400_bad_request(r); 1351 } 1352 } 1353 1354 /* check age of nonce. Note, random data is used in nonce generation 1355 * in mod_auth_send_401_unauthorized_digest(). If that were replaced 1356 * with nanosecond time, then nonce secret would remain unique enough 1357 * for the purposes of Digest auth, and would be reproducible (and 1358 * verifiable) if nanoseconds were included with seconds as part of the 1359 * nonce "timestamp:secret". However, doing so would expose a high 1360 * precision timestamp of the system to attackers. timestamp in nonce 1361 * could theoretically be modified and still produce same md5sum, but 1362 * that is highly unlikely within a 10 min (moving) window of valid 1363 * time relative to current time (now). 1364 * If it is desired to validate that nonces were generated by server, 1365 * then specify auth.require = ( ... => ( "secret" => "..." ) ) 1366 * When secret is specified, then instead of nanoseconds, the random 1367 * data value (included for unique nonces) will be exposed in the nonce 1368 * along with the timestamp, and the additional secret will be used to 1369 * validate that the server generated the nonce using that secret. */ 1370 int send_nextnonce; 1371 { 1372 time_t ts = 0; 1373 const unsigned char * const nonce_uns = (unsigned char *)nonce; 1374 for (i = 0; i < 8 && light_isxdigit(nonce_uns[i]); ++i) { 1375 ts = (ts << 4) + hex2int(nonce_uns[i]); 1376 } 1377 const time_t cur_ts = log_epoch_secs; 1378 if (nonce[i] != ':' 1379 || ts > cur_ts || cur_ts - ts > 600) { /*(10 mins)*/ 1380 /* nonce is stale; have client regenerate digest */ 1381 buffer_free(b); 1382 return mod_auth_send_401_unauthorized_digest(r, require, ai.dalgo); 1383 } 1384 1385 send_nextnonce = (cur_ts - ts > 540); /*(9 mins)*/ 1386 1387 if (require->nonce_secret) { 1388 unsigned int rnd = 0; 1389 for (int j = i+8; i < j && light_isxdigit(nonce_uns[i]); ++i) { 1390 rnd = (rnd << 4) + hex2int(nonce_uns[i]); 1391 } 1392 if (nonce[i] != ':') { 1393 /* nonce is invalid; 1394 * expect extra field w/ require->nonce_secret */ 1395 log_error(r->conf.errh, __FILE__, __LINE__, 1396 "digest: nonce invalid"); 1397 buffer_free(b); 1398 return mod_auth_send_400_bad_request(r); 1399 } 1400 buffer * const tb = r->tmp_buf; 1401 buffer_clear(tb); 1402 mod_auth_append_nonce(tb, cur_ts, require, ai.dalgo, (int *)&rnd); 1403 if (!buffer_eq_slen(tb, nonce, strlen(nonce))) { 1404 /* nonce not generated using current require->nonce_secret */ 1405 log_error(r->conf.errh, __FILE__, __LINE__, 1406 "digest: nonce mismatch"); 1407 buffer_free(b); 1408 return mod_auth_send_401_unauthorized_digest(r, require, 0); 1409 } 1410 } 1411 } 1412 1413 handler_t rc = HANDLER_UNSET; 1414 1415 plugin_data * const p = p_d; 1416 splay_tree ** sptree = p->conf.auth_cache 1417 ? &p->conf.auth_cache->sptree 1418 : NULL; 1419 http_auth_cache_entry *ae = NULL; 1420 int ndx = -1; 1421 if (sptree) { 1422 ndx = http_auth_cache_hash(require, ai.username, ai.ulen); 1423 ae = http_auth_cache_query(sptree, ndx); 1424 if (ae && ae->require == require 1425 && ae->dalgo == ai.dalgo 1426 && ae->dlen == ai.dlen 1427 && ae->ulen == ai.ulen 1428 && 0 == memcmp(ae->username, ai.username, ai.ulen)) { 1429 rc = HANDLER_GO_ON; 1430 memcpy(ai.digest, ae->pwdigest, ai.dlen); 1431 } 1432 else /*(not found or hash collision)*/ 1433 ae = NULL; 1434 } 1435 1436 if (HANDLER_UNSET == rc) 1437 rc = backend->digest(r, backend->p_d, &ai); 1438 1439 switch (rc) { 1440 case HANDLER_GO_ON: 1441 break; 1442 case HANDLER_WAIT_FOR_EVENT: 1443 buffer_free(b); 1444 return HANDLER_WAIT_FOR_EVENT; 1445 case HANDLER_FINISHED: 1446 buffer_free(b); 1447 return HANDLER_FINISHED; 1448 case HANDLER_ERROR: 1449 default: 1450 r->keep_alive = 0; /*(disable keep-alive if unknown user)*/ 1451 buffer_free(b); 1452 return mod_auth_send_401_unauthorized_digest(r, require, 0); 1453 } 1454 1455 if (sptree && NULL == ae) { /*(cache digest from backend)*/ 1456 ae = http_auth_cache_entry_init(require, ai.dalgo, ai.username, ai.ulen, 1457 (char *)ai.digest, ai.dlen); 1458 http_auth_cache_insert(sptree, ndx, ae, http_auth_cache_entry_free); 1459 } 1460 1461 const char *m = get_http_method_name(r->http_method); 1462 force_assert(m); 1463 1464 mod_auth_digest_mutate(&ai,m,uri,nonce,cnonce,nc,qop); 1465 1466 if (!http_auth_const_time_memeq(rdigest, ai.digest, ai.dlen)) { 1467 /* digest not ok */ 1468 log_error(r->conf.errh, __FILE__, __LINE__, 1469 "digest: auth failed for %s: wrong password, IP: %s", 1470 username, r->con->dst_addr_buf->ptr); 1471 r->keep_alive = 0; /*(disable keep-alive if bad password)*/ 1472 1473 buffer_free(b); 1474 return mod_auth_send_401_unauthorized_digest(r, require, 0); 1475 } 1476 1477 /* value is our allow-rules */ 1478 if (!http_auth_match_rules(require, username, NULL, NULL)) { 1479 buffer_free(b); 1480 return mod_auth_send_401_unauthorized_digest(r, require, 0); 1481 } 1482 1483 if (send_nextnonce) { 1484 /*(send nextnonce when expiration is approaching)*/ 1485 buffer * const tb = r->tmp_buf; 1486 const time_t cur_ts = log_epoch_secs; 1487 mod_auth_digest_authentication_info(tb, cur_ts, require, ai.dalgo); 1488 http_header_response_set(r, HTTP_HEADER_OTHER, 1489 CONST_STR_LEN("Authentication-Info"), 1490 CONST_BUF_LEN(tb)); 1491 } 1492 1493 http_auth_setenv(r, ai.username, ai.ulen, CONST_STR_LEN("Digest")); 1494 1495 buffer_free(b); 1496 1497 return HANDLER_GO_ON; 1498 } 1499 1500 static handler_t mod_auth_send_401_unauthorized_digest(request_st * const r, const struct http_auth_require_t * const require, int nonce_stale) { 1501 buffer * const tb = r->tmp_buf; 1502 mod_auth_digest_www_authenticate(tb, log_epoch_secs, require, nonce_stale); 1503 http_header_response_set(r, HTTP_HEADER_OTHER, CONST_STR_LEN("WWW-Authenticate"), CONST_BUF_LEN(tb)); 1504 1505 r->http_status = 401; 1506 r->handler_module = NULL; 1507 return HANDLER_FINISHED; 1508 } 1509 1510 static handler_t mod_auth_check_extern(request_st * const r, void *p_d, const struct http_auth_require_t * const require, const struct http_auth_backend_t * const backend) { 1511 /* require REMOTE_USER already set */ 1512 const buffer *vb = http_header_env_get(r, CONST_STR_LEN("REMOTE_USER")); 1513 UNUSED(p_d); 1514 UNUSED(backend); 1515 if (NULL != vb && http_auth_match_rules(require, vb->ptr, NULL, NULL)) { 1516 return HANDLER_GO_ON; 1517 } else { 1518 r->http_status = 401; 1519 r->handler_module = NULL; 1520 return HANDLER_FINISHED; 1521 } 1522 } 1523