trust/trustd/SecOCSPCache.c

   1 /*
   2  * Copyright (c) 2009-2010,2012-2017 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*
  25  *  SecOCSPCache.c - securityd
  26  */
  27
  28 #include <CoreFoundation/CFUtilities.h>
  29 #include <CoreFoundation/CFString.h>
  30 #include "trust/trustd/SecOCSPCache.h"
  31 #include "trust/trustd/SecTrustLoggingServer.h"
  32 #include <utilities/debugging.h>
  33 #include <Security/SecCertificateInternal.h>
  34 #include <Security/SecFramework.h>
  35 #include <Security/SecInternal.h>
  36 #include <AssertMacros.h>
  37 #include <stdlib.h>
  38 #include <limits.h>
  39 #include <sys/stat.h>
  40 #include <asl.h>
  41 #include "utilities/SecCFWrappers.h"
  42 #include "utilities/SecDb.h"
  43 #include "utilities/SecFileLocations.h"
  44 #include "utilities/iOSforOSX.h"
  45
  46 /* Note that lastUsed is actually time of insert because we don't
  47    refresh lastUsed on each SELECT. */
  48
  49 #define flushSQL  CFSTR("DELETE FROM responses")
  50 #define expireSQL  CFSTR("DELETE FROM responses WHERE expires<?")
  51 #define insertResponseSQL  CFSTR("INSERT INTO responses " \
  52     "(ocspResponse,responderURI,expires,lastUsed) VALUES (?,?,?,?)")
  53 #define insertLinkSQL  CFSTR("INSERT INTO ocsp (hashAlgorithm," \
  54     "issuerNameHash,issuerPubKeyHash,serialNum,responseId) VALUES (?,?,?,?,?)")
  55 #define deleteResponseSQL  CFSTR("DELETE FROM responses WHERE responseId=?")
  56 #define selectHashAlgorithmSQL  CFSTR("SELECT DISTINCT hashAlgorithm " \
  57     "FROM ocsp WHERE serialNum=?")
  58 #define selectResponseSQL  CFSTR("SELECT ocspResponse,responseId FROM " \
  59     "responses WHERE lastUsed>? AND responseId=(SELECT responseId FROM ocsp WHERE " \
  60     "issuerNameHash=? AND issuerPubKeyHash=? AND serialNum=? AND hashAlgorithm=?)" \
  61     " ORDER BY expires DESC")
  62
  63 #define kSecOCSPCacheFileName CFSTR("ocspcache.sqlite3")
  64
  65
  66 // MARK; -
  67 // MARK: SecOCSPCacheDb
  68
  69 static SecDbRef SecOCSPCacheDbCreate(CFStringRef path) {
  70     return SecDbCreate(path, 0600, true, true, true, true, 1,
  71             ^bool (SecDbRef db, SecDbConnectionRef dbconn, bool didCreate, bool *callMeAgainForNextConnection, CFErrorRef *error) {
  72         __block bool ok = true;
  73
  74         CFErrorRef localError = NULL;
  75         if (!SecDbWithSQL(dbconn, selectHashAlgorithmSQL /* expireSQL */, &localError, NULL) && CFErrorGetCode(localError) == SQLITE_ERROR) {
  76             /* SecDbWithSQL returns SQLITE_ERROR if the table we are preparing the above statement for doesn't exist. */
  77             ok &= SecDbTransaction(dbconn, kSecDbExclusiveTransactionType, error, ^(bool *commit) {
  78                 ok &= SecDbExec(dbconn,
  79                     CFSTR("CREATE TABLE ocsp("
  80                           "issuerNameHash BLOB NOT NULL,"
  81                           "issuerPubKeyHash BLOB NOT NULL,"
  82                           "serialNum BLOB NOT NULL,"
  83                           "hashAlgorithm BLOB NOT NULL,"
  84                           "responseId INTEGER NOT NULL"
  85                           ");"
  86                           "CREATE INDEX iResponseId ON ocsp(responseId);"
  87                           "CREATE INDEX iserialNum ON ocsp(serialNum);"
  88                           "CREATE INDEX iSNumDAlg ON ocsp(serialNum,hashAlgorithm);"
  89                           "CREATE TABLE responses("
  90                           "responseId INTEGER PRIMARY KEY,"
  91                           "ocspResponse BLOB NOT NULL,"
  92                           "responderURI BLOB,"
  93                           "expires DOUBLE NOT NULL,"
  94                           "lastUsed DOUBLE NOT NULL"
  95                           ");"
  96                           "CREATE INDEX iexpires ON responses(expires);"
  97                           "CREATE TRIGGER tocspdel BEFORE DELETE ON responses FOR EACH ROW "
  98                           "BEGIN "
  99                           "DELETE FROM ocsp WHERE responseId=OLD.responseId;"
 100                           " END;"), error);
 101                 *commit = ok;
 102             });
 103         }
 104         CFReleaseSafe(localError);
 105         if (!ok) {
 106             secerror("%s failed: %@", didCreate ? "Create" : "Open", error ? *error : NULL);
 107             CFIndex errCode = errSecInternalComponent;
 108             if (error && *error) {
 109                 errCode = CFErrorGetCode(*error);
 110             }
 111             TrustdHealthAnalyticsLogErrorCodeForDatabase(TAOCSPCache,
 112                                                          didCreate ? TAOperationCreate : TAOperationOpen,
 113                                                          TAFatalError, errCode);
 114         }
 115         return ok;
 116     });
 117 }
 118
 119 // MARK; -
 120 // MARK: SecOCSPCache
 121
 122 typedef struct __SecOCSPCache *SecOCSPCacheRef;
 123 struct __SecOCSPCache {
 124         SecDbRef db;
 125 };
 126
 127 static dispatch_once_t kSecOCSPCacheOnce;
 128 static SecOCSPCacheRef kSecOCSPCache = NULL;
 129
 130 static SecOCSPCacheRef SecOCSPCacheCreate(CFStringRef db_name) {
 131         SecOCSPCacheRef this;
 132
 133         require(this = (SecOCSPCacheRef)malloc(sizeof(struct __SecOCSPCache)), errOut);
 134     require(this->db = SecOCSPCacheDbCreate(db_name), errOut);
 135
 136         return this;
 137
 138 errOut:
 139         if (this) {
 140         CFReleaseSafe(this->db);
 141                 free(this);
 142         }
 143
 144         return NULL;
 145 }
 146
 147 static CFStringRef SecOCSPCacheCopyPath(void) {
 148     CFStringRef ocspRelPath = kSecOCSPCacheFileName;
 149 #if TARGET_OS_IPHONE
 150     CFURLRef ocspURL = SecCopyURLForFileInKeychainDirectory(ocspRelPath);
 151     if (!ocspURL) {
 152         ocspURL = SecCopyURLForFileInUserCacheDirectory(ocspRelPath);
 153     }
 154 #else
 155     /* macOS caches should be in user cache dir */
 156     CFURLRef ocspURL = SecCopyURLForFileInUserCacheDirectory(ocspRelPath);
 157 #endif
 158     CFStringRef ocspPath = NULL;
 159     if (ocspURL) {
 160         ocspPath = CFURLCopyFileSystemPath(ocspURL, kCFURLPOSIXPathStyle);
 161         CFRelease(ocspURL);
 162     }
 163     return ocspPath;
 164 }
 165
 166 static void SecOCSPCacheWith(void(^cacheJob)(SecOCSPCacheRef cache)) {
 167     dispatch_once(&kSecOCSPCacheOnce, ^{
 168         CFStringRef dbPath = SecOCSPCacheCopyPath();
 169         if (dbPath) {
 170             kSecOCSPCache = SecOCSPCacheCreate(dbPath);
 171             CFRelease(dbPath);
 172         }
 173     });
 174     // Do pre job run work here (cancel idle timers etc.)
 175     cacheJob(kSecOCSPCache);
 176     // Do post job run work here (gc timer, etc.)
 177 }
 178
 179 static bool _SecOCSPCacheExpireWithTransaction(SecDbConnectionRef dbconn, CFAbsoluteTime now, CFErrorRef *error) {
 180     //if (now > nextExpireTime)
 181     {
 182         return SecDbWithSQL(dbconn, expireSQL, error, ^bool(sqlite3_stmt *expire) {
 183             return SecDbBindDouble(expire, 1, now, error) &&
 184             SecDbStep(dbconn, expire, error, NULL);
 185         });
 186         // TODO: Write now + expireDelay to nextExpireTime;
 187         // currently we try to expire entries on each cache write
 188     }
 189 }
 190
 191 /* Instance implementation. */
 192
 193 static void _SecOCSPCacheReplaceResponse(SecOCSPCacheRef this,
 194     SecOCSPResponseRef oldResponse, SecOCSPResponseRef ocspResponse,
 195     CFURLRef localResponderURI, CFAbsoluteTime verifyTime) {
 196     secdebug("ocspcache", "adding response from %@", localResponderURI);
 197     /* responses.ocspResponse */
 198
 199     // TODO: Update a latestProducedAt value using date in new entry, to ensure forward movement of time.
 200     // Set "now" to the new producedAt we are receiving here if localTime is before this date.
 201     // In addition whenever we run though here, check to see if "now" is more than past
 202     // the nextCacheExpireDate and expire the cache if it is.
 203     CFDataRef responseData = SecOCSPResponseGetData(ocspResponse);
 204     __block CFErrorRef localError = NULL;
 205     __block bool ok = true;
 206     ok &= SecDbPerformWrite(this->db, &localError, ^(SecDbConnectionRef dbconn) {
 207         ok &= SecDbTransaction(dbconn, kSecDbExclusiveTransactionType, &localError, ^(bool *commit) {
 208             __block sqlite3_int64 responseId;
 209             if (oldResponse && (responseId = SecOCSPResponseGetID(oldResponse)) >= 0) {
 210                 ok &= SecDbWithSQL(dbconn, deleteResponseSQL, &localError, ^bool(sqlite3_stmt *deleteResponse) {
 211                     ok &= SecDbBindInt64(deleteResponse, 1, responseId, &localError);
 212                     /* Execute the delete statement. */
 213                     ok &= SecDbStep(dbconn, deleteResponse, &localError, NULL);
 214                     return ok;
 215                 });
 216             }
 217
 218             ok &= SecDbWithSQL(dbconn, insertResponseSQL, &localError, ^bool(sqlite3_stmt *insertResponse) {
 219                 ok &= SecDbBindBlob(insertResponse, 1,
 220                                     CFDataGetBytePtr(responseData),
 221                                     CFDataGetLength(responseData),
 222                                     SQLITE_TRANSIENT, &localError);
 223
 224                 /* responses.responderURI */
 225                 if (ok) {
 226                     CFDataRef uriData = NULL;
 227                     if (localResponderURI) {
 228                         uriData = CFURLCreateData(kCFAllocatorDefault, localResponderURI,
 229                                                   kCFStringEncodingUTF8, false);
 230                     }
 231                     if (uriData) {
 232                         ok = SecDbBindBlob(insertResponse, 2,
 233                                            CFDataGetBytePtr(uriData),
 234                                            CFDataGetLength(uriData),
 235                                            SQLITE_TRANSIENT, &localError);
 236                         CFRelease(uriData);
 237                     }
 238                 }
 239                 /* responses.expires */
 240                 ok &= SecDbBindDouble(insertResponse, 3,
 241                                       SecOCSPResponseGetExpirationTime(ocspResponse),
 242                                       &localError);
 243                 /* responses.lastUsed */
 244                 ok &= SecDbBindDouble(insertResponse, 4,
 245                                       verifyTime,
 246                                       &localError);
 247
 248                 /* Execute the insert statement. */
 249                 ok &= SecDbStep(dbconn, insertResponse, &localError, NULL);
 250
 251                 responseId = sqlite3_last_insert_rowid(SecDbHandle(dbconn));
 252                 return ok;
 253             });
 254
 255             /* Now add a link record for every singleResponse in the ocspResponse. */
 256             ok &= SecDbWithSQL(dbconn, insertLinkSQL, &localError, ^bool(sqlite3_stmt *insertLink) {
 257                 SecAsn1OCSPSingleResponse **responses;
 258                 for (responses = ocspResponse->responseData.responses;
 259                      *responses; ++responses) {
 260                     SecAsn1OCSPSingleResponse *resp = *responses;
 261                     SecAsn1OCSPCertID *certId = &resp->certID;
 262                     ok &= SecDbBindBlob(insertLink, 1,
 263                                         certId->algId.algorithm.Data,
 264                                         certId->algId.algorithm.Length,
 265                                         SQLITE_TRANSIENT, &localError);
 266                     ok &= SecDbBindBlob(insertLink, 2,
 267                                         certId->issuerNameHash.Data,
 268                                         certId->issuerNameHash.Length,
 269                                         SQLITE_TRANSIENT, &localError);
 270                     ok &= SecDbBindBlob(insertLink, 3,
 271                                         certId->issuerPubKeyHash.Data,
 272                                         certId->issuerPubKeyHash.Length,
 273                                         SQLITE_TRANSIENT, &localError);
 274                     ok &= SecDbBindBlob(insertLink, 4,
 275                                         certId->serialNumber.Data,
 276                                         certId->serialNumber.Length,
 277                                         SQLITE_TRANSIENT, &localError);
 278                     ok &= SecDbBindInt64(insertLink, 5, responseId, &localError);
 279
 280                     /* Execute the insert statement. */
 281                     ok &= SecDbStep(dbconn, insertLink, &localError, NULL);
 282                     ok &= SecDbReset(insertLink, &localError);
 283                 }
 284                 return ok;
 285             });
 286
 287             // Remove expired entries here.
 288             // TODO: Consider only doing this once per 24 hours or something.
 289             ok &= _SecOCSPCacheExpireWithTransaction(dbconn, verifyTime, &localError);
 290             if (!ok)
 291                 *commit = false;
 292         });
 293     });
 294     if (!ok) {
 295         secerror("_SecOCSPCacheAddResponse failed: %@", localError);
 296         TrustdHealthAnalyticsLogErrorCodeForDatabase(TAOCSPCache, TAOperationWrite, TAFatalError,
 297                                                      localError ? CFErrorGetCode(localError) : errSecInternalComponent);
 298         CFReleaseNull(localError);
 299     }
 300     CFReleaseSafe(localError);
 301 }
 302
 303 static SecOCSPResponseRef _SecOCSPCacheCopyMatching(SecOCSPCacheRef this,
 304     SecOCSPRequestRef request, CFURLRef responderURI, CFAbsoluteTime minInsertTime) {
 305     const DERItem *publicKey;
 306     CFDataRef issuer = NULL;
 307     CFDataRef serial = NULL;
 308     __block SecOCSPResponseRef response = NULL;
 309     __block CFErrorRef localError = NULL;
 310     __block bool ok = true;
 311
 312     require(publicKey = SecCertificateGetPublicKeyData(request->issuer), errOut);
 313     require(issuer = SecCertificateCopyIssuerSequence(request->certificate), errOut);
 314     require(serial = SecCertificateCopySerialNumberData(request->certificate, NULL), errOut);
 315
 316     ok &= SecDbPerformRead(this->db, &localError, ^(SecDbConnectionRef dbconn) {
 317         ok &= SecDbWithSQL(dbconn, selectHashAlgorithmSQL, &localError, ^bool(sqlite3_stmt *selectHash) {
 318             ok = SecDbBindBlob(selectHash, 1, CFDataGetBytePtr(serial), CFDataGetLength(serial), SQLITE_TRANSIENT, &localError);
 319             ok &= SecDbStep(dbconn, selectHash, &localError, ^(bool *stopHash) {
 320                 SecAsn1Oid algorithm;
 321                 algorithm.Data = (uint8_t *)sqlite3_column_blob(selectHash, 0);
 322                 algorithm.Length = sqlite3_column_bytes(selectHash, 0);
 323
 324                 /* Calculate the issuerKey and issuerName digests using the returned
 325                  hashAlgorithm. */
 326                 CFDataRef issuerNameHash = SecDigestCreate(kCFAllocatorDefault,
 327                                                            &algorithm, NULL, CFDataGetBytePtr(issuer), CFDataGetLength(issuer));
 328                 CFDataRef issuerPubKeyHash = SecDigestCreate(kCFAllocatorDefault,
 329                                                              &algorithm, NULL, publicKey->data, publicKey->length);
 330
 331                 if (issuerNameHash && issuerPubKeyHash && ok) ok &= SecDbWithSQL(dbconn, selectResponseSQL, &localError, ^bool(sqlite3_stmt *selectResponse) {
 332                     /* Now we have the serial, algorithm, issuerNameHash and
 333                      issuerPubKeyHash so let's lookup the db entry. */
 334                     ok &= SecDbBindDouble(selectResponse, 1, minInsertTime, &localError);
 335                     ok &= SecDbBindBlob(selectResponse, 2, CFDataGetBytePtr(issuerNameHash),
 336                                         CFDataGetLength(issuerNameHash), SQLITE_TRANSIENT, &localError);
 337                     ok &= SecDbBindBlob(selectResponse, 3, CFDataGetBytePtr(issuerPubKeyHash),
 338                                         CFDataGetLength(issuerPubKeyHash), SQLITE_TRANSIENT, &localError);
 339                     ok &= SecDbBindBlob(selectResponse, 4, CFDataGetBytePtr(serial),
 340                                         CFDataGetLength(serial), SQLITE_TRANSIENT, &localError);
 341                     ok &= SecDbBindBlob(selectResponse, 5, algorithm.Data,
 342                                         algorithm.Length, SQLITE_TRANSIENT, &localError);
 343                     ok &= SecDbStep(dbconn, selectResponse, &localError, ^(bool *stopResponse) {
 344                         /* Found an entry! */
 345                         secdebug("ocspcache", "found cached response");
 346                         CFDataRef resp = CFDataCreate(kCFAllocatorDefault,
 347                                                       sqlite3_column_blob(selectResponse, 0),
 348                                                       sqlite3_column_bytes(selectResponse, 0));
 349                         sqlite3_int64 responseID = sqlite3_column_int64(selectResponse, 1);
 350                         if (resp) {
 351                             SecOCSPResponseRef new_response = SecOCSPResponseCreateWithID(resp, responseID);
 352                             if (response) {
 353                                 if (SecOCSPResponseProducedAt(response) < SecOCSPResponseProducedAt(new_response)) {
 354                                     SecOCSPResponseFinalize(response);
 355                                     response = new_response;
 356                                 } else {
 357                                     SecOCSPResponseFinalize(new_response);
 358                                 }
 359                             } else {
 360                                 response = new_response;
 361                             }
 362                             CFRelease(resp);
 363                         }
 364                     });
 365                     return ok;
 366                 });
 367
 368                 CFReleaseSafe(issuerNameHash);
 369                 CFReleaseSafe(issuerPubKeyHash);
 370             });
 371             return ok;
 372         });
 373     });
 374
 375 errOut:
 376     CFReleaseSafe(serial);
 377     CFReleaseSafe(issuer);
 378
 379     if (!ok || localError) {
 380         secerror("ocsp cache lookup failed: %@", localError);
 381         if (response) {
 382             SecOCSPResponseFinalize(response);
 383             response = NULL;
 384         }
 385         TrustdHealthAnalyticsLogErrorCodeForDatabase(TAOCSPCache, TAOperationRead, TAFatalError,
 386                                                      localError ? CFErrorGetCode(localError) : errSecInternalComponent);
 387     }
 388     CFReleaseSafe(localError);
 389
 390     secdebug("ocspcache", "returning %s", (response ? "cached response" : "NULL"));
 391
 392     return response;
 393 }
 394
 395 static bool _SecOCSPCacheFlush(SecOCSPCacheRef cache, CFErrorRef *error) {
 396     __block CFErrorRef localError = NULL;
 397     __block bool ok = true;
 398
 399     ok &= SecDbPerformWrite(cache->db, &localError, ^(SecDbConnectionRef dbconn) {
 400         ok &= SecDbExec(dbconn, flushSQL, &localError);
 401     });
 402     if (!ok || localError) {
 403         TrustdHealthAnalyticsLogErrorCodeForDatabase(TAOCSPCache, TAOperationWrite, TAFatalError,
 404                                                      localError ? CFErrorGetCode(localError) : errSecInternalComponent);
 405     }
 406     (void) CFErrorPropagate(localError, error);
 407
 408     return ok;
 409 }
 410
 411
 412 /* Public API */
 413
 414 void SecOCSPCacheReplaceResponse(SecOCSPResponseRef old_response, SecOCSPResponseRef response,
 415     CFURLRef localResponderURI, CFAbsoluteTime verifyTime) {
 416     SecOCSPCacheWith(^(SecOCSPCacheRef cache) {
 417         _SecOCSPCacheReplaceResponse(cache, old_response, response, localResponderURI, verifyTime);
 418     });
 419 }
 420
 421 SecOCSPResponseRef SecOCSPCacheCopyMatching(SecOCSPRequestRef request,
 422     CFURLRef localResponderURI /* may be NULL */) {
 423     __block SecOCSPResponseRef response = NULL;
 424     SecOCSPCacheWith(^(SecOCSPCacheRef cache) {
 425         response = _SecOCSPCacheCopyMatching(cache, request, localResponderURI, 0.0);
 426     });
 427     return response;
 428 }
 429
 430 SecOCSPResponseRef SecOCSPCacheCopyMatchingWithMinInsertTime(SecOCSPRequestRef request,
 431     CFURLRef localResponderURI, CFAbsoluteTime minInsertTime) {
 432     __block SecOCSPResponseRef response = NULL;
 433     SecOCSPCacheWith(^(SecOCSPCacheRef cache) {
 434         response = _SecOCSPCacheCopyMatching(cache, request, localResponderURI, minInsertTime);
 435     });
 436     return response;
 437 }
 438
 439 bool SecOCSPCacheFlush(CFErrorRef *error) {
 440     __block bool result = false;
 441     SecOCSPCacheWith(^(SecOCSPCacheRef cache) {
 442         result = _SecOCSPCacheFlush(cache, error);
 443     });
 444     return result;
 445 }