ceph/src/rgw/rgw_auth_s3.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #ifndef CEPH_RGW_AUTH_S3_H
   5 #define CEPH_RGW_AUTH_S3_H
   6
   7 #include <array>
   8 #include <memory>
   9 #include <string>
  10 #include <tuple>
  11
  12 #include <boost/algorithm/string.hpp>
  13 #include <boost/container/static_vector.hpp>
  14 #include <boost/utility/string_ref.hpp>
  15 #include <boost/utility/string_view.hpp>
  16
  17 #include "common/sstring.hh"
  18 #include "rgw_common.h"
  19 #include "rgw_rest_s3.h"
  20
  21 #include "rgw_auth.h"
  22 #include "rgw_auth_filters.h"
  23 #include "rgw_auth_keystone.h"
  24
  25
  26 namespace rgw {
  27 namespace auth {
  28 namespace s3 {
  29
  30 static constexpr auto RGW_AUTH_GRACE = std::chrono::minutes{15};
  31
  32 // returns true if the request time is within RGW_AUTH_GRACE of the current time
  33 bool is_time_skew_ok(time_t t);
  34
  35 class ExternalAuthStrategy : public rgw::auth::Strategy,
  36                              public rgw::auth::RemoteApplier::Factory {
  37   typedef rgw::auth::IdentityApplier::aplptr_t aplptr_t;
  38   RGWRados* const store;
  39   rgw::auth::ImplicitTenants& implicit_tenant_context;
  40
  41   using keystone_config_t = rgw::keystone::CephCtxConfig;
  42   using keystone_cache_t = rgw::keystone::TokenCache;
  43   using EC2Engine = rgw::auth::keystone::EC2Engine;
  44
  45   boost::optional <EC2Engine> keystone_engine;
  46   LDAPEngine ldap_engine;
  47
  48   aplptr_t create_apl_remote(CephContext* const cct,
  49                              const req_state* const s,
  50                              rgw::auth::RemoteApplier::acl_strategy_t&& acl_alg,
  51                              const rgw::auth::RemoteApplier::AuthInfo info
  52                             ) const override {
  53     auto apl = rgw::auth::add_sysreq(cct, store, s,
  54       rgw::auth::RemoteApplier(cct, store, std::move(acl_alg), info,
  55                                implicit_tenant_context,
  56                                rgw::auth::ImplicitTenants::IMPLICIT_TENANTS_S3));
  57     /* TODO(rzarzynski): replace with static_ptr. */
  58     return aplptr_t(new decltype(apl)(std::move(apl)));
  59   }
  60
  61 public:
  62   ExternalAuthStrategy(CephContext* const cct,
  63                        RGWRados* const store,
  64                        rgw::auth::ImplicitTenants& implicit_tenant_context,
  65                        AWSEngine::VersionAbstractor* const ver_abstractor)
  66     : store(store),
  67       implicit_tenant_context(implicit_tenant_context),
  68       ldap_engine(cct, store, *ver_abstractor,
  69                   static_cast<rgw::auth::RemoteApplier::Factory*>(this)) {
  70
  71     if (cct->_conf->rgw_s3_auth_use_keystone &&
  72         ! cct->_conf->rgw_keystone_url.empty()) {
  73
  74       keystone_engine.emplace(cct, ver_abstractor,
  75                               static_cast<rgw::auth::RemoteApplier::Factory*>(this),
  76                               keystone_config_t::get_instance(),
  77                               keystone_cache_t::get_instance<keystone_config_t>());
  78       add_engine(Control::SUFFICIENT, *keystone_engine);
  79
  80     }
  81
  82     if (cct->_conf->rgw_s3_auth_use_ldap &&
  83         ! cct->_conf->rgw_ldap_uri.empty()) {
  84       add_engine(Control::SUFFICIENT, ldap_engine);
  85     }
  86   }
  87
  88   const char* get_name() const noexcept override {
  89     return "rgw::auth::s3::AWSv2ExternalAuthStrategy";
  90   }
  91 };
  92
  93
  94 template <class AbstractorT,
  95           bool AllowAnonAccessT = false>
  96 class AWSAuthStrategy : public rgw::auth::Strategy,
  97                         public rgw::auth::LocalApplier::Factory {
  98   typedef rgw::auth::IdentityApplier::aplptr_t aplptr_t;
  99
 100   static_assert(std::is_base_of<rgw::auth::s3::AWSEngine::VersionAbstractor,
 101                                 AbstractorT>::value,
 102                 "AbstractorT must be a subclass of rgw::auth::s3::VersionAbstractor");
 103
 104   RGWRados* const store;
 105   AbstractorT ver_abstractor;
 106
 107   S3AnonymousEngine anonymous_engine;
 108   ExternalAuthStrategy external_engines;
 109   LocalEngine local_engine;
 110
 111   aplptr_t create_apl_local(CephContext* const cct,
 112                             const req_state* const s,
 113                             const RGWUserInfo& user_info,
 114                             const std::string& subuser) const override {
 115     auto apl = rgw::auth::add_sysreq(cct, store, s,
 116       rgw::auth::LocalApplier(cct, user_info, subuser));
 117     /* TODO(rzarzynski): replace with static_ptr. */
 118     return aplptr_t(new decltype(apl)(std::move(apl)));
 119   }
 120
 121 public:
 122   AWSAuthStrategy(CephContext* const cct,
 123                   rgw::auth::ImplicitTenants& implicit_tenant_context,
 124                   RGWRados* const store)
 125     : store(store),
 126       ver_abstractor(cct),
 127       anonymous_engine(cct,
 128                        static_cast<rgw::auth::LocalApplier::Factory*>(this)),
 129       external_engines(cct, store, implicit_tenant_context, &ver_abstractor),
 130       local_engine(cct, store, ver_abstractor,
 131                    static_cast<rgw::auth::LocalApplier::Factory*>(this)) {
 132     /* The anynoymous auth. */
 133     if (AllowAnonAccessT) {
 134       add_engine(Control::SUFFICIENT, anonymous_engine);
 135     }
 136
 137     /* The external auth. */
 138     Control local_engine_mode;
 139     if (! external_engines.is_empty()) {
 140       add_engine(Control::SUFFICIENT, external_engines);
 141
 142       local_engine_mode = Control::FALLBACK;
 143     } else {
 144       local_engine_mode = Control::SUFFICIENT;
 145     }
 146
 147     /* The local auth. */
 148     if (cct->_conf->rgw_s3_auth_use_rados) {
 149       add_engine(local_engine_mode, local_engine);
 150     }
 151   }
 152
 153   const char* get_name() const noexcept override {
 154     return "rgw::auth::s3::AWSAuthStrategy";
 155   }
 156 };
 157
 158
 159 class AWSv4ComplMulti : public rgw::auth::Completer,
 160                         public rgw::io::DecoratedRestfulClient<rgw::io::RestfulClient*>,
 161                         public std::enable_shared_from_this<AWSv4ComplMulti> {
 162   using io_base_t = rgw::io::DecoratedRestfulClient<rgw::io::RestfulClient*>;
 163   using signing_key_t = std::array<unsigned char,
 164                                    CEPH_CRYPTO_HMACSHA256_DIGESTSIZE>;
 165
 166   CephContext* const cct;
 167
 168   const boost::string_view date;
 169   const boost::string_view credential_scope;
 170   const signing_key_t signing_key;
 171
 172   class ChunkMeta {
 173     size_t data_offset_in_stream = 0;
 174     size_t data_length = 0;
 175     std::string signature;
 176
 177     ChunkMeta(const size_t data_starts_in_stream,
 178               const size_t data_length,
 179               const boost::string_ref signature)
 180       : data_offset_in_stream(data_starts_in_stream),
 181         data_length(data_length),
 182         signature(signature.to_string()) {
 183     }
 184
 185     ChunkMeta(const boost::string_view& signature)
 186       : signature(signature.to_string()) {
 187     }
 188
 189   public:
 190     static constexpr size_t SIG_SIZE = 64;
 191
 192     /* Let's suppose the data length fields can't exceed uint64_t. */
 193     static constexpr size_t META_MAX_SIZE = \
 194       sarrlen("\r\nffffffffffffffff;chunk-signature=") + SIG_SIZE + sarrlen("\r\n");
 195
 196     /* The metadata size of for the last, empty chunk. */
 197     static constexpr size_t META_MIN_SIZE = \
 198       sarrlen("0;chunk-signature=") + SIG_SIZE + sarrlen("\r\n");
 199
 200     /* Detect whether a given stream_pos fits in boundaries of a chunk. */
 201     bool is_new_chunk_in_stream(size_t stream_pos) const;
 202
 203     /* Get the remaining data size. */
 204     size_t get_data_size(size_t stream_pos) const;
 205
 206     const std::string& get_signature() const {
 207       return signature;
 208     }
 209
 210     /* Factory: create an object representing metadata of first, initial chunk
 211      * in a stream. */
 212     static ChunkMeta create_first(const boost::string_view& seed_signature) {
 213       return ChunkMeta(seed_signature);
 214     }
 215
 216     /* Factory: parse a block of META_MAX_SIZE bytes and creates an object
 217      * representing non-first chunk in a stream. As the process is sequential
 218      * and depends on the previous chunk, caller must pass it. */
 219     static std::pair<ChunkMeta, size_t> create_next(CephContext* cct,
 220                                                     ChunkMeta&& prev,
 221                                                     const char* metabuf,
 222                                                     size_t metabuf_len);
 223   } chunk_meta;
 224
 225   size_t stream_pos;
 226   boost::container::static_vector<char, ChunkMeta::META_MAX_SIZE> parsing_buf;
 227   ceph::crypto::SHA256* sha256_hash;
 228   std::string prev_chunk_signature;
 229
 230   bool is_signature_mismatched();
 231   std::string calc_chunk_signature(const std::string& payload_hash) const;
 232
 233 public:
 234   /* We need the constructor to be public because of the std::make_shared that
 235    * is employed by the create() method. */
 236   AWSv4ComplMulti(const req_state* const s,
 237                   boost::string_view date,
 238                   boost::string_view credential_scope,
 239                   boost::string_view seed_signature,
 240                   const signing_key_t& signing_key)
 241     : io_base_t(nullptr),
 242       cct(s->cct),
 243       date(std::move(date)),
 244       credential_scope(std::move(credential_scope)),
 245       signing_key(signing_key),
 246
 247       /* The evolving state. */
 248       chunk_meta(ChunkMeta::create_first(seed_signature)),
 249       stream_pos(0),
 250       sha256_hash(calc_hash_sha256_open_stream()),
 251       prev_chunk_signature(std::move(seed_signature)) {
 252   }
 253
 254   ~AWSv4ComplMulti() {
 255     if (sha256_hash) {
 256       calc_hash_sha256_close_stream(&sha256_hash);
 257     }
 258   }
 259
 260   /* rgw::io::DecoratedRestfulClient. */
 261   size_t recv_body(char* buf, size_t max) override;
 262
 263   /* rgw::auth::Completer. */
 264   void modify_request_state(req_state* s_rw) override;
 265   bool complete() override;
 266
 267   /* Factories. */
 268   static cmplptr_t create(const req_state* s,
 269                           boost::string_view date,
 270                           boost::string_view credential_scope,
 271                           boost::string_view seed_signature,
 272                           const boost::optional<std::string>& secret_key);
 273
 274 };
 275
 276 class AWSv4ComplSingle : public rgw::auth::Completer,
 277                          public rgw::io::DecoratedRestfulClient<rgw::io::RestfulClient*>,
 278                          public std::enable_shared_from_this<AWSv4ComplSingle> {
 279   using io_base_t = rgw::io::DecoratedRestfulClient<rgw::io::RestfulClient*>;
 280
 281   CephContext* const cct;
 282   const char* const expected_request_payload_hash;
 283   ceph::crypto::SHA256* sha256_hash = nullptr;
 284
 285 public:
 286   /* Defined in rgw_auth_s3.cc because of get_v4_exp_payload_hash(). We need
 287    * the constructor to be public because of the std::make_shared employed by
 288    * the create() method. */
 289   AWSv4ComplSingle(const req_state* const s);
 290
 291   ~AWSv4ComplSingle() {
 292     if (sha256_hash) {
 293       calc_hash_sha256_close_stream(&sha256_hash);
 294     }
 295   }
 296
 297   /* rgw::io::DecoratedRestfulClient. */
 298   size_t recv_body(char* buf, size_t max) override;
 299
 300   /* rgw::auth::Completer. */
 301   void modify_request_state(req_state* s_rw) override;
 302   bool complete() override;
 303
 304   /* Factories. */
 305   static cmplptr_t create(const req_state* s,
 306                           const boost::optional<std::string>&);
 307
 308 };
 309
 310 } /* namespace s3 */
 311 } /* namespace auth */
 312 } /* namespace rgw */
 313
 314 void rgw_create_s3_canonical_header(
 315   const char *method,
 316   const char *content_md5,
 317   const char *content_type,
 318   const char *date,
 319   const std::map<std::string, std::string>& meta_map,
 320   const char *request_uri,
 321   const std::map<std::string, std::string>& sub_resources,
 322   std::string& dest_str);
 323 bool rgw_create_s3_canonical_header(const req_info& info,
 324                                     utime_t *header_time,       /* out */
 325                                     std::string& dest,          /* out */
 326                                     bool qsr);
 327 static inline std::tuple<bool, std::string, utime_t>
 328 rgw_create_s3_canonical_header(const req_info& info, const bool qsr) {
 329   std::string dest;
 330   utime_t header_time;
 331
 332   const bool ok = rgw_create_s3_canonical_header(info, &header_time, dest, qsr);
 333   return std::make_tuple(ok, dest, header_time);
 334 }
 335
 336 namespace rgw {
 337 namespace auth {
 338 namespace s3 {
 339
 340 static constexpr char AWS4_HMAC_SHA256_STR[] = "AWS4-HMAC-SHA256";
 341 static constexpr char AWS4_HMAC_SHA256_PAYLOAD_STR[] = "AWS4-HMAC-SHA256-PAYLOAD";
 342
 343 static constexpr char AWS4_EMPTY_PAYLOAD_HASH[] = \
 344   "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855";
 345
 346 static constexpr char AWS4_UNSIGNED_PAYLOAD_HASH[] = "UNSIGNED-PAYLOAD";
 347
 348 static constexpr char AWS4_STREAMING_PAYLOAD_HASH[] = \
 349   "STREAMING-AWS4-HMAC-SHA256-PAYLOAD";
 350
 351 int parse_credentials(const req_info& info,                     /* in */
 352                       boost::string_view& access_key_id,        /* out */
 353                       boost::string_view& credential_scope,     /* out */
 354                       boost::string_view& signedheaders,        /* out */
 355                       boost::string_view& signature,            /* out */
 356                       boost::string_view& date,                 /* out */
 357                       bool& using_qs);                          /* out */
 358
 359 static inline std::string get_v4_canonical_uri(const req_info& info) {
 360   /* The code should normalize according to RFC 3986 but S3 does NOT do path
 361    * normalization that SigV4 typically does. This code follows the same
 362    * approach that boto library. See auth.py:canonical_uri(...). */
 363
 364   std::string canonical_uri = info.request_uri_aws4;
 365
 366   if (canonical_uri.empty()) {
 367     canonical_uri = "/";
 368   } else {
 369     boost::replace_all(canonical_uri, "+", "%20");
 370   }
 371
 372   return canonical_uri;
 373 }
 374
 375 static inline const char* get_v4_exp_payload_hash(const req_info& info)
 376 {
 377   /* In AWSv4 the hash of real, transfered payload IS NOT necessary to form
 378    * a Canonical Request, and thus verify a Signature. x-amz-content-sha256
 379    * header lets get the information very early -- before seeing first byte
 380    * of HTTP body. As a consequence, we can decouple Signature verification
 381    * from payload's fingerprint check. */
 382   const char *expected_request_payload_hash = \
 383     info.env->get("HTTP_X_AMZ_CONTENT_SHA256");
 384
 385   if (!expected_request_payload_hash) {
 386     /* An HTTP client MUST send x-amz-content-sha256. The single exception
 387      * is the case of using the Query Parameters where "UNSIGNED-PAYLOAD"
 388      * literals are used for crafting Canonical Request:
 389      *
 390      *  You don't include a payload hash in the Canonical Request, because
 391      *  when you create a presigned URL, you don't know the payload content
 392      *  because the URL is used to upload an arbitrary payload. Instead, you
 393      *  use a constant string UNSIGNED-PAYLOAD. */
 394     expected_request_payload_hash = AWS4_UNSIGNED_PAYLOAD_HASH;
 395   }
 396
 397   return expected_request_payload_hash;
 398 }
 399
 400 static inline bool is_v4_payload_unsigned(const char* const exp_payload_hash)
 401 {
 402   return boost::equals(exp_payload_hash, AWS4_UNSIGNED_PAYLOAD_HASH);
 403 }
 404
 405 static inline bool is_v4_payload_empty(const req_state* const s)
 406 {
 407   /* from rfc2616 - 4.3 Message Body
 408    *
 409    * "The presence of a message-body in a request is signaled by the inclusion
 410    * of a Content-Length or Transfer-Encoding header field in the request's
 411    * message-headers." */
 412   return s->content_length == 0 &&
 413          s->info.env->get("HTTP_TRANSFER_ENCODING") == nullptr;
 414 }
 415
 416 static inline bool is_v4_payload_streamed(const char* const exp_payload_hash)
 417 {
 418   return boost::equals(exp_payload_hash, AWS4_STREAMING_PAYLOAD_HASH);
 419 }
 420
 421 std::string get_v4_canonical_qs(const req_info& info, bool using_qs);
 422
 423 boost::optional<std::string>
 424 get_v4_canonical_headers(const req_info& info,
 425                          const boost::string_view& signedheaders,
 426                          bool using_qs,
 427                          bool force_boto2_compat);
 428
 429 extern sha256_digest_t
 430 get_v4_canon_req_hash(CephContext* cct,
 431                       const boost::string_view& http_verb,
 432                       const std::string& canonical_uri,
 433                       const std::string& canonical_qs,
 434                       const std::string& canonical_hdrs,
 435                       const boost::string_view& signed_hdrs,
 436                       const boost::string_view& request_payload_hash);
 437
 438 AWSEngine::VersionAbstractor::string_to_sign_t
 439 get_v4_string_to_sign(CephContext* cct,
 440                       const boost::string_view& algorithm,
 441                       const boost::string_view& request_date,
 442                       const boost::string_view& credential_scope,
 443                       const sha256_digest_t& canonreq_hash);
 444
 445 extern AWSEngine::VersionAbstractor::server_signature_t
 446 get_v4_signature(const boost::string_view& credential_scope,
 447                  CephContext* const cct,
 448                  const boost::string_view& secret_key,
 449                  const AWSEngine::VersionAbstractor::string_to_sign_t& string_to_sign);
 450
 451 extern AWSEngine::VersionAbstractor::server_signature_t
 452 get_v2_signature(CephContext*,
 453                  const std::string& secret_key,
 454                  const AWSEngine::VersionAbstractor::string_to_sign_t& string_to_sign);
 455
 456 } /* namespace s3 */
 457 } /* namespace auth */
 458 } /* namespace rgw */
 459
 460 #endif