src/common/cynara.cpp

   1 /*
   2  *  Copyright (c) 2014 Samsung Electronics Co., Ltd All Rights Reserved
   3  *
   4  *  Contact: Rafal Krypa <r.krypa@samsung.com>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License
  17  */
  18 /*
  19  * @file        cynara.cpp
  20  * @author      Rafal Krypa <r.krypa@samsung.com>
  21  * @brief       Wrapper class for Cynara interface
  22  */
  23
  24 #include <cstring>
  25 #include "cynara.h"
  26
  27 #include <dpl/log/log.h>
  28
  29 namespace SecurityManager {
  30
  31 /**
  32  * Rules for apps and users are organized into set of buckets stored in Cynara.
  33  * Bucket is set of rules (app, uid, privilege) -> (DENY, ALLOW, BUCKET, ...).
  34  *  |------------------------|
  35  *  |      <<allow>>         |
  36  *  |   PRIVACY_MANAGER      |
  37  *  |------------------------|
  38  *  |  A    U   P      policy|
  39  *  |------------------------|
  40  *  | app1 uid1 priv1  DENY  |
  41  *  |  *   uid2 priv2  DENY  |
  42  *  |  * * *      Bucket:MAIN|
  43  *  |------------------------|
  44  *
  45  * For details about buckets see Cynara documentation.
  46  *
  47  * Security Manager currently defines 8 buckets:
  48  * - PRIVACY_MANAGER - first bucket during search (which is actually default bucket
  49  *   with empty string as id). If user specifies his preference then required rule
  50  *   is created here.
  51  * - MAIN            - holds rules denied by manufacturer, redirects to MANIFESTS
  52  *   bucket and holds entries for each user pointing to User Type
  53  *   specific buckets
  54  * - MANIFESTS       - stores rules needed by installed apps (from package
  55  *   manifest)
  56  * - USER_TYPE_ADMIN
  57  * - USER_TYPE_SYSTEM
  58  * - USER_TYPE_NORMAL
  59  * - USER_TYPE_GUEST - they store privileges from templates for apropriate
  60  *   user type. ALLOW rules only.
  61  * - ADMIN           - stores custom rules introduced by device administrator.
  62  *   Ignored if no matching rule found.
  63  *
  64  * Below is basic layout of buckets:
  65  *
  66  *  |------------------------|
  67  *  |      <<allow>>         |
  68  *  |   PRIVACY_MANAGER      |
  69  *  |                        |
  70  *  |  * * *      Bucket:MAIN|                         |------------------|
  71  *  |------------------------|                         |      <<deny>>    |
  72  *             |                                    |->|     MANIFESTS    |
  73  *             -----------------                    |  |                  |
  74  *                             |                    |  |------------------|
  75  *                             V                    |
  76  *                     |------------------------|   |
  77  *                     |       <<deny>>         |---|
  78  *                     |         MAIN           |
  79  * |---------------|   |                        |     |-------------------|
  80  * |    <<deny>>   |<--| * * *  Bucket:MANIFESTS|---->|      <<deny>>     |
  81  * | USER_TYPE_SYST|   |------------------------|     |  USER_TYPE_NORMAL |
  82  * |               |        |              |          |                   |
  83  * |---------------|        |              |          |-------------------|
  84  *        |                 |              |                    |
  85  *        |                 V              V                    |
  86  *        |      |---------------|      |---------------|       |
  87  *        |      |    <<deny>>   |      |    <<deny>>   |       |
  88  *        |      |USER_TYPE_GUEST|      |USER_TYPE_ADMIN|       |
  89  *        |      |               |      |               |       |
  90  *        |      |---------------|      |---------------|       |
  91  *        |              |                      |               |
  92  *        |              |----             -----|               |
  93  *        |                  |             |                    |
  94  *        |                  V             V                    |
  95  *        |                |------------------|                 |
  96  *        |------------->  |     <<none>>     | <---------------|
  97  *                         |       ADMIN      |
  98  *                         |                  |
  99  *                         |------------------|
 100  *
 101  */
 102 CynaraAdmin::BucketsMap CynaraAdmin::Buckets =
 103 {
 104     { Bucket::PRIVACY_MANAGER, std::string(CYNARA_ADMIN_DEFAULT_BUCKET)},
 105     { Bucket::MAIN, std::string("MAIN")},
 106     { Bucket::USER_TYPE_ADMIN, std::string("USER_TYPE_ADMIN")},
 107     { Bucket::USER_TYPE_NORMAL, std::string("USER_TYPE_NORMAL")},
 108     { Bucket::USER_TYPE_GUEST, std::string("USER_TYPE_GUEST") },
 109     { Bucket::USER_TYPE_SYSTEM, std::string("USER_TYPE_SYSTEM")},
 110     { Bucket::ADMIN, std::string("ADMIN")},
 111     { Bucket::MANIFESTS, std::string("MANIFESTS")},
 112 };
 113
 114
 115 CynaraAdminPolicy::CynaraAdminPolicy(const std::string &client, const std::string &user,
 116         const std::string &privilege, Operation operation,
 117         const std::string &bucket)
 118 {
 119     this->client = strdup(client.c_str());
 120     this->user = strdup(user.c_str());
 121     this->privilege = strdup(privilege.c_str());
 122     this->bucket = strdup(bucket.c_str());
 123
 124     if (this->bucket == nullptr || this->client == nullptr ||
 125         this->user == nullptr || this->privilege == nullptr) {
 126         free(this->bucket);
 127         free(this->client);
 128         free(this->user);
 129         free(this->privilege);
 130         ThrowMsg(CynaraException::OutOfMemory,
 131                 std::string("Error in CynaraAdminPolicy allocation."));
 132     }
 133
 134     this->result = static_cast<int>(operation);
 135     this->result_extra = nullptr;
 136 }
 137
 138 CynaraAdminPolicy::CynaraAdminPolicy(const std::string &client, const std::string &user,
 139     const std::string &privilege, const std::string &goToBucket,
 140     const std::string &bucket)
 141 {
 142     this->bucket = strdup(bucket.c_str());
 143     this->client = strdup(client.c_str());
 144     this->user = strdup(user.c_str());
 145     this->privilege = strdup(privilege.c_str());
 146     this->result_extra = strdup(goToBucket.c_str());
 147     this->result = CYNARA_ADMIN_BUCKET;
 148
 149     if (this->bucket == nullptr || this->client == nullptr ||
 150         this->user == nullptr || this->privilege == nullptr ||
 151         this->result_extra == nullptr) {
 152         free(this->bucket);
 153         free(this->client);
 154         free(this->user);
 155         free(this->privilege);
 156         free(this->result_extra);
 157         ThrowMsg(CynaraException::OutOfMemory,
 158                 std::string("Error in CynaraAdminPolicy allocation."));
 159     }
 160 }
 161
 162 CynaraAdminPolicy::CynaraAdminPolicy(CynaraAdminPolicy &&that)
 163 {
 164     bucket = that.bucket;
 165     client = that.client;
 166     user = that.user;
 167     privilege = that.privilege;
 168     result_extra = that.result_extra;
 169     result = that.result;
 170
 171     that.bucket = nullptr;
 172     that.client = nullptr;
 173     that.user = nullptr;
 174     that.privilege = nullptr;
 175     that.result_extra = nullptr;
 176 }
 177
 178 CynaraAdminPolicy::~CynaraAdminPolicy()
 179 {
 180     free(this->bucket);
 181     free(this->client);
 182     free(this->user);
 183     free(this->privilege);
 184     free(this->result_extra);
 185 }
 186
 187 static bool checkCynaraError(int result, const std::string &msg)
 188 {
 189     switch (result) {
 190         case CYNARA_API_SUCCESS:
 191         case CYNARA_API_ACCESS_ALLOWED:
 192             return true;
 193         case CYNARA_API_ACCESS_DENIED:
 194             return false;
 195         case CYNARA_API_OUT_OF_MEMORY:
 196             ThrowMsg(CynaraException::OutOfMemory, msg);
 197         case CYNARA_API_INVALID_PARAM:
 198             ThrowMsg(CynaraException::InvalidParam, msg);
 199         case CYNARA_API_SERVICE_NOT_AVAILABLE:
 200             ThrowMsg(CynaraException::ServiceNotAvailable, msg);
 201         case CYNARA_API_BUCKET_NOT_FOUND:
 202             ThrowMsg(CynaraException::BucketNotFound, msg);
 203         default:
 204             ThrowMsg(CynaraException::UnknownError, msg);
 205     }
 206 }
 207
 208 CynaraAdmin::CynaraAdmin()
 209 {
 210     checkCynaraError(
 211         cynara_admin_initialize(&m_CynaraAdmin),
 212         "Cannot connect to Cynara administrative interface.");
 213 }
 214
 215 CynaraAdmin::~CynaraAdmin()
 216 {
 217     cynara_admin_finish(m_CynaraAdmin);
 218 }
 219
 220 CynaraAdmin &CynaraAdmin::getInstance()
 221 {
 222     static CynaraAdmin cynaraAdmin;
 223     return cynaraAdmin;
 224 }
 225
 226 void CynaraAdmin::SetPolicies(const std::vector<CynaraAdminPolicy> &policies)
 227 {
 228     std::vector<const struct cynara_admin_policy *> pp_policies(policies.size() + 1);
 229
 230     LogDebug("Sending " << policies.size() << " policies to Cynara");
 231     for (std::size_t i = 0; i < policies.size(); ++i) {
 232         pp_policies[i] = static_cast<const struct cynara_admin_policy *>(&policies[i]);
 233         LogDebug("policies[" << i << "] = {" <<
 234             ".bucket = " << pp_policies[i]->bucket << ", " <<
 235             ".client = " << pp_policies[i]->client << ", " <<
 236             ".user = " << pp_policies[i]->user << ", " <<
 237             ".privilege = " << pp_policies[i]->privilege << ", " <<
 238             ".result = " << pp_policies[i]->result << ", " <<
 239             ".result_extra = " << pp_policies[i]->result_extra << "}");
 240     }
 241
 242     pp_policies[policies.size()] = nullptr;
 243
 244     checkCynaraError(
 245         cynara_admin_set_policies(m_CynaraAdmin, pp_policies.data()),
 246         "Error while updating Cynara policy.");
 247 }
 248
 249 void CynaraAdmin::UpdateAppPolicy(
 250     const std::string &label,
 251     const std::string &user,
 252     const std::vector<std::string> &oldPrivileges,
 253     const std::vector<std::string> &newPrivileges)
 254 {
 255     std::vector<CynaraAdminPolicy> policies;
 256
 257     // Perform sort-merge join on oldPrivileges and newPrivileges.
 258     // Assume that they are already sorted and without duplicates.
 259     auto oldIter = oldPrivileges.begin();
 260     auto newIter = newPrivileges.begin();
 261
 262     while (oldIter != oldPrivileges.end() && newIter != newPrivileges.end()) {
 263         int compare = oldIter->compare(*newIter);
 264         if (compare == 0) {
 265             LogDebug("(user = " << user << " label = " << label << ") " <<
 266                 "keeping privilege " << *newIter);
 267             ++oldIter;
 268             ++newIter;
 269             continue;
 270         } else if (compare < 0) {
 271             LogDebug("(user = " << user << " label = " << label << ") " <<
 272                 "removing privilege " << *oldIter);
 273             policies.push_back(CynaraAdminPolicy(label, user, *oldIter,
 274                     CynaraAdminPolicy::Operation::Delete,
 275                     Buckets.at(Bucket::MANIFESTS)));
 276             ++oldIter;
 277         } else {
 278             LogDebug("(user = " << user << " label = " << label << ") " <<
 279                 "adding privilege " << *newIter);
 280             policies.push_back(CynaraAdminPolicy(label, user, *newIter,
 281                     CynaraAdminPolicy::Operation::Allow,
 282                     Buckets.at(Bucket::MANIFESTS)));
 283             ++newIter;
 284         }
 285     }
 286
 287     for (; oldIter != oldPrivileges.end(); ++oldIter) {
 288         LogDebug("(user = " << user << " label = " << label << ") " <<
 289             "removing privilege " << *oldIter);
 290         policies.push_back(CynaraAdminPolicy(label, user, *oldIter,
 291                     CynaraAdminPolicy::Operation::Delete,
 292                     Buckets.at(Bucket::MANIFESTS)));
 293     }
 294
 295     for (; newIter != newPrivileges.end(); ++newIter) {
 296         LogDebug("(user = " << user << " label = " << label << ") " <<
 297             "adding privilege " << *newIter);
 298         policies.push_back(CynaraAdminPolicy(label, user, *newIter,
 299                     CynaraAdminPolicy::Operation::Allow,
 300                     Buckets.at(Bucket::MANIFESTS)));
 301     }
 302
 303     SetPolicies(policies);
 304 }
 305
 306 void CynaraAdmin::UserInit(uid_t uid, security_manager_user_type userType)
 307 {
 308     Bucket bucket;
 309     std::vector<CynaraAdminPolicy> policies;
 310
 311     switch (userType) {
 312         case SM_USER_TYPE_SYSTEM:
 313             bucket = Bucket::USER_TYPE_SYSTEM;
 314             break;
 315         case SM_USER_TYPE_ADMIN:
 316             bucket = Bucket::USER_TYPE_ADMIN;
 317             break;
 318         case SM_USER_TYPE_GUEST:
 319             bucket = Bucket::USER_TYPE_GUEST;
 320             break;
 321         case SM_USER_TYPE_NORMAL:
 322             bucket = Bucket::USER_TYPE_NORMAL;
 323             break;
 324         case SM_USER_TYPE_ANY:
 325         case SM_USER_TYPE_NONE:
 326         case SM_USER_TYPE_END:
 327         default:
 328             ThrowMsg(CynaraException::InvalidParam, "User type incorrect");
 329     }
 330
 331     policies.push_back(CynaraAdminPolicy(CYNARA_ADMIN_WILDCARD,
 332                                             std::to_string(static_cast<unsigned int>(uid)),
 333                                             CYNARA_ADMIN_WILDCARD,
 334                                             Buckets.at(bucket),
 335                                             Buckets.at(Bucket::MAIN)));
 336
 337     CynaraAdmin::getInstance().SetPolicies(policies);
 338 }
 339
 340 void CynaraAdmin::ListPolicies(
 341     const std::string &bucketName,
 342     const std::string &appId,
 343     const std::string &user,
 344     const std::string &privilege,
 345     std::vector<CynaraAdminPolicy> &policies)
 346 {
 347     struct cynara_admin_policy ** pp_policies = nullptr;
 348
 349     checkCynaraError(
 350         cynara_admin_list_policies(m_CynaraAdmin, bucketName.c_str(), appId.c_str(),
 351             user.c_str(), privilege.c_str(), &pp_policies),
 352         "Error while getting list of policies for bucket: " + bucketName);
 353
 354     for (std::size_t i = 0; pp_policies[i] != nullptr; i++) {
 355         policies.push_back(std::move(*static_cast<CynaraAdminPolicy*>(pp_policies[i])));
 356
 357         free(pp_policies[i]);
 358     }
 359
 360     free(pp_policies);
 361
 362 }
 363
 364 void CynaraAdmin::EmptyBucket(const std::string &bucketName, bool recursive, const std::string &client,
 365     const std::string &user, const std::string &privilege)
 366 {
 367     checkCynaraError(
 368         cynara_admin_erase(m_CynaraAdmin, bucketName.c_str(), static_cast<int>(recursive),
 369             client.c_str(), user.c_str(), privilege.c_str()),
 370         "Error while emptying bucket: " + bucketName + ", filter (C, U, P): " +
 371             client + ", " + user + ", " + privilege);
 372 }
 373
 374 Cynara::Cynara()
 375 {
 376     checkCynaraError(
 377         cynara_initialize(&m_Cynara, nullptr),
 378         "Cannot connect to Cynara policy interface.");
 379 }
 380
 381 Cynara::~Cynara()
 382 {
 383     cynara_finish(m_Cynara);
 384 }
 385
 386 Cynara &Cynara::getInstance()
 387 {
 388     static Cynara cynara;
 389     return cynara;
 390 }
 391
 392 bool Cynara::check(const std::string &label, const std::string &privilege,
 393         const std::string &user, const std::string &session)
 394 {
 395     return checkCynaraError(
 396         cynara_check(m_Cynara,
 397             label.c_str(), session.c_str(), user.c_str(), privilege.c_str()),
 398         "Cannot check permission with Cynara.");
 399 }
 400
 401 } // namespace SecurityManager