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