OSX/sec/securityd/SecOCSPCache.c

   1 /*
   2  * Copyright (c) 2009-2010,2012-2015 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 <securityd/SecOCSPCache.h>
  31 #include <utilities/debugging.h>
  32 #include <Security/SecCertificateInternal.h>
  33 #include <Security/SecFramework.h>
  34 #include <Security/SecInternal.h>
  35 #include <AssertMacros.h>
  36 #include <stdlib.h>
  37 #include <limits.h>
  38 #include <sys/stat.h>
  39 #include <asl.h>
  40 #include "utilities/SecDb.h"
  41 #include "utilities/SecFileLocations.h"
  42 #include "utilities/iOSforOSX.h"
  43
  44 /* Note that lastUsed is actually time of insert because we don't
  45    refresh lastUsed on each SELECT. */
  46
  47 #define expireSQL  CFSTR("DELETE FROM responses WHERE expires<?")
  48 #define insertResponseSQL  CFSTR("INSERT INTO responses " \
  49     "(ocspResponse,responderURI,expires,lastUsed) VALUES (?,?,?,?)")
  50 #define insertLinkSQL  CFSTR("INSERT INTO ocsp (hashAlgorithm," \
  51     "issuerNameHash,issuerPubKeyHash,serialNum,responseId) VALUES (?,?,?,?,?)")
  52 #define deleteResponseSQL  CFSTR("DELETE FROM responses WHERE responseId=?")
  53 #define selectHashAlgorithmSQL  CFSTR("SELECT DISTINCT hashAlgorithm " \
  54     "FROM ocsp WHERE serialNum=?")
  55 #define selectResponseSQL  CFSTR("SELECT ocspResponse,responseId FROM " \
  56     "responses WHERE lastUsed>? AND responseId=(SELECT responseId FROM ocsp WHERE " \
  57     "issuerNameHash=? AND issuerPubKeyHash=? AND serialNum=? AND hashAlgorithm=?)" \
  58     " ORDER BY expires DESC")
  59
  60 #define kSecOCSPCacheFileName CFSTR("ocspcache.sqlite3")
  61
  62
  63 // MARK; -
  64 // MARK: SecOCSPCacheDb
  65
  66 static SecDbRef SecOCSPCacheDbCreate(CFStringRef path) {
  67     return SecDbCreate(path, ^bool (SecDbConnectionRef dbconn, bool didCreate, bool *callMeAgainForNextConnection, CFErrorRef *error) {
  68         __block bool ok;
  69         ok = (SecDbExec(dbconn, CFSTR("PRAGMA auto_vacuum = FULL"), error) &&
  70               SecDbExec(dbconn, CFSTR("PRAGMA journal_mode = WAL"), error));
  71         CFErrorRef localError = NULL;
  72         if (ok && !SecDbWithSQL(dbconn, selectHashAlgorithmSQL /* expireSQL */, &localError, NULL) && CFErrorGetCode(localError) == SQLITE_ERROR) {
  73             /* SecDbWithSQL returns SQLITE_ERROR if the table we are preparing the above statement for doesn't exist. */
  74             ok &= SecDbTransaction(dbconn, kSecDbExclusiveTransactionType, error, ^(bool *commit) {
  75                 ok = SecDbExec(dbconn,
  76                     CFSTR("CREATE TABLE ocsp("
  77                           "issuerNameHash BLOB NOT NULL,"
  78                           "issuerPubKeyHash BLOB NOT NULL,"
  79                           "serialNum BLOB NOT NULL,"
  80                           "hashAlgorithm BLOB NOT NULL,"
  81                           "responseId INTEGER NOT NULL"
  82                           ");"
  83                           "CREATE INDEX iResponseId ON ocsp(responseId);"
  84                           "CREATE INDEX iserialNum ON ocsp(serialNum);"
  85                           "CREATE INDEX iSNumDAlg ON ocsp(serialNum,hashAlgorithm);"
  86                           "CREATE TABLE responses("
  87                           "responseId INTEGER PRIMARY KEY,"
  88                           "ocspResponse BLOB NOT NULL,"
  89                           "responderURI BLOB,"
  90                           "expires DOUBLE NOT NULL,"
  91                           "lastUsed DOUBLE NOT NULL"
  92                           ");"
  93                           "CREATE INDEX iexpires ON responses(expires);"
  94                           "CREATE TRIGGER tocspdel BEFORE DELETE ON responses FOR EACH ROW "
  95                           "BEGIN "
  96                           "DELETE FROM ocsp WHERE responseId=OLD.responseId;"
  97                           " END;"), error);
  98                 *commit = ok;
  99             });
 100         }
 101         CFReleaseSafe(localError);
 102         if (!ok)
 103             secerror("%s failed: %@", didCreate ? "Create" : "Open", error ? *error : NULL);
 104         return ok;
 105     });
 106 }
 107
 108 // MARK; -
 109 // MARK: SecOCSPCache
 110
 111 typedef struct __SecOCSPCache *SecOCSPCacheRef;
 112 struct __SecOCSPCache {
 113         SecDbRef db;
 114 };
 115
 116 static dispatch_once_t kSecOCSPCacheOnce;
 117 static SecOCSPCacheRef kSecOCSPCache = NULL;
 118
 119 static SecOCSPCacheRef SecOCSPCacheCreate(CFStringRef db_name) {
 120         SecOCSPCacheRef this;
 121
 122         require(this = (SecOCSPCacheRef)malloc(sizeof(struct __SecOCSPCache)), errOut);
 123     require(this->db = SecOCSPCacheDbCreate(db_name), errOut);
 124
 125         return this;
 126
 127 errOut:
 128         if (this) {
 129         CFReleaseSafe(this->db);
 130                 free(this);
 131         }
 132
 133         return NULL;
 134 }
 135
 136 static CFStringRef SecOCSPCacheCopyPath(void) {
 137     CFStringRef ocspRelPath = kSecOCSPCacheFileName;
 138     CFURLRef ocspURL = SecCopyURLForFileInKeychainDirectory(ocspRelPath);
 139     if (!ocspURL) {
 140         ocspURL = SecCopyURLForFileInUserCacheDirectory(ocspRelPath);
 141     }
 142     CFStringRef ocspPath = NULL;
 143     if (ocspURL) {
 144         ocspPath = CFURLCopyFileSystemPath(ocspURL, kCFURLPOSIXPathStyle);
 145         CFRelease(ocspURL);
 146     }
 147     return ocspPath;
 148 }
 149
 150 static void SecOCSPCacheWith(void(^cacheJob)(SecOCSPCacheRef cache)) {
 151     dispatch_once(&kSecOCSPCacheOnce, ^{
 152         CFStringRef dbPath = SecOCSPCacheCopyPath();
 153         if (dbPath) {
 154             kSecOCSPCache = SecOCSPCacheCreate(dbPath);
 155             CFRelease(dbPath);
 156         }
 157     });
 158     // Do pre job run work here (cancel idle timers etc.)
 159     cacheJob(kSecOCSPCache);
 160     // Do post job run work here (gc timer, etc.)
 161 }
 162
 163 static bool _SecOCSPCacheExpireWithTransaction(SecDbConnectionRef dbconn, CFAbsoluteTime now, CFErrorRef *error) {
 164     //if (now > nextExpireTime)
 165     {
 166         return SecDbWithSQL(dbconn, expireSQL, error, ^bool(sqlite3_stmt *expire) {
 167             return SecDbBindDouble(expire, 1, now, error) &&
 168             SecDbStep(dbconn, expire, error, NULL);
 169         });
 170         // TODO: Write now + expireDelay to nextExpireTime;
 171         // currently we try to expire entries on each cache write
 172     }
 173 }
 174
 175 /* Instance implementation. */
 176
 177 static void _SecOCSPCacheReplaceResponse(SecOCSPCacheRef this,
 178     SecOCSPResponseRef oldResponse, SecOCSPResponseRef ocspResponse,
 179     CFURLRef localResponderURI, CFAbsoluteTime verifyTime) {
 180     secdebug("ocspcache", "adding response from %@", localResponderURI);
 181     /* responses.ocspResponse */
 182
 183     // TODO: Update a latestProducedAt value using date in new entry, to ensure forward movement of time.
 184     // Set "now" to the new producedAt we are receiving here if localTime is before this date.
 185     // In addition whenever we run though here, check to see if "now" is more than past
 186     // the nextCacheExpireDate and expire the cache if it is.
 187     CFDataRef responseData = SecOCSPResponseGetData(ocspResponse);
 188     __block CFErrorRef localError = NULL;
 189     __block bool ok = true;
 190     ok &= SecDbPerformWrite(this->db, &localError, ^(SecDbConnectionRef dbconn) {
 191         ok &= SecDbTransaction(dbconn, kSecDbExclusiveTransactionType, &localError, ^(bool *commit) {
 192             __block sqlite3_int64 responseId;
 193             if (oldResponse && (responseId = SecOCSPResponseGetID(oldResponse)) >= 0) {
 194                 ok = SecDbWithSQL(dbconn, deleteResponseSQL, &localError, ^bool(sqlite3_stmt *deleteResponse) {
 195                     ok = SecDbBindInt64(deleteResponse, 1, responseId, &localError);
 196                     /* Execute the delete statement. */
 197                     if (ok)
 198                         ok = SecDbStep(dbconn, deleteResponse, &localError, NULL);
 199                     return ok;
 200                 });
 201             }
 202
 203             if (ok) ok = SecDbWithSQL(dbconn, insertResponseSQL, &localError, ^bool(sqlite3_stmt *insertResponse) {
 204                 if (ok)
 205                     ok = SecDbBindBlob(insertResponse, 1,
 206                                        CFDataGetBytePtr(responseData),
 207                                        CFDataGetLength(responseData),
 208                                        SQLITE_TRANSIENT, &localError);
 209
 210                 /* responses.responderURI */
 211                 if (ok) {
 212                     CFDataRef uriData = NULL;
 213                     if (localResponderURI) {
 214                         uriData = CFURLCreateData(kCFAllocatorDefault, localResponderURI,
 215                                                   kCFStringEncodingUTF8, false);
 216                     }
 217                     if (uriData) {
 218                         ok = SecDbBindBlob(insertResponse, 2,
 219                                            CFDataGetBytePtr(uriData),
 220                                            CFDataGetLength(uriData),
 221                                            SQLITE_TRANSIENT, &localError);
 222                         CFRelease(uriData);
 223                     } else {
 224                         // Since we use SecDbClearBindings this shouldn't be needed.
 225                         //ok = SecDbBindNull(insertResponse, 2, &localError);
 226                     }
 227                 }
 228                 /* responses.expires */
 229                 if (ok)
 230                     ok = SecDbBindDouble(insertResponse, 3,
 231                                          SecOCSPResponseGetExpirationTime(ocspResponse),
 232                                          &localError);
 233                 /* responses.lastUsed */
 234                 if (ok)
 235                     ok = SecDbBindDouble(insertResponse, 4,
 236                                          verifyTime,
 237                                          &localError);
 238
 239                 /* Execute the insert statement. */
 240                 if (ok)
 241                     ok = SecDbStep(dbconn, insertResponse, &localError, NULL);
 242
 243                 responseId = sqlite3_last_insert_rowid(SecDbHandle(dbconn));
 244                 return ok;
 245             });
 246
 247             /* Now add a link record for every singleResponse in the ocspResponse. */
 248             if (ok) ok = SecDbWithSQL(dbconn, insertLinkSQL, &localError, ^bool(sqlite3_stmt *insertLink) {
 249                 SecAsn1OCSPSingleResponse **responses;
 250                 for (responses = ocspResponse->responseData.responses;
 251                      *responses; ++responses) {
 252                     SecAsn1OCSPSingleResponse *resp = *responses;
 253                     SecAsn1OCSPCertID *certId = &resp->certID;
 254                     if (ok) ok = SecDbBindBlob(insertLink, 1,
 255                                                certId->algId.algorithm.Data,
 256                                                certId->algId.algorithm.Length,
 257                                                SQLITE_TRANSIENT, &localError);
 258                     if (ok) ok = SecDbBindBlob(insertLink, 2,
 259                                                certId->issuerNameHash.Data,
 260                                                certId->issuerNameHash.Length,
 261                                                SQLITE_TRANSIENT, &localError);
 262                     if (ok) ok = SecDbBindBlob(insertLink, 3,
 263                                                certId->issuerPubKeyHash.Data,
 264                                                certId->issuerPubKeyHash.Length,
 265                                                SQLITE_TRANSIENT, &localError);
 266                     if (ok) ok = SecDbBindBlob(insertLink, 4,
 267                                                certId->serialNumber.Data,
 268                                                certId->serialNumber.Length,
 269                                                SQLITE_TRANSIENT, &localError);
 270                     if (ok) ok = SecDbBindInt64(insertLink, 5, responseId, &localError);
 271
 272                     /* Execute the insert statement. */
 273                     if (ok) ok = SecDbStep(dbconn, insertLink, &localError, NULL);
 274                     if (ok) ok = SecDbReset(insertLink, &localError);
 275                 }
 276                 return ok;
 277             });
 278
 279             // Remove expired entries here.
 280             // TODO: Consider only doing this once per 24 hours or something.
 281             if (ok) ok = _SecOCSPCacheExpireWithTransaction(dbconn, verifyTime, &localError);
 282             if (!ok)
 283                 *commit = false;
 284         });
 285     });
 286     if (!ok) {
 287         secerror("_SecOCSPCacheAddResponse failed: %@", localError);
 288     }
 289     CFReleaseSafe(localError);
 290 }
 291
 292 static SecOCSPResponseRef _SecOCSPCacheCopyMatching(SecOCSPCacheRef this,
 293     SecOCSPRequestRef request, CFURLRef responderURI, CFAbsoluteTime minInsertTime) {
 294     const DERItem *publicKey;
 295     CFDataRef issuer = NULL;
 296     CFDataRef serial = NULL;
 297     __block SecOCSPResponseRef response = NULL;
 298     __block CFErrorRef localError = NULL;
 299     __block bool ok = true;
 300
 301     require(publicKey = SecCertificateGetPublicKeyData(request->issuer), errOut);
 302     require(issuer = SecCertificateCopyIssuerSequence(request->certificate), errOut);
 303 #if (TARGET_OS_MAC && !(TARGET_OS_EMBEDDED || TARGET_OS_IPHONE))
 304     require(serial = SecCertificateCopySerialNumber(request->certificate, NULL), errOut);
 305 #else
 306     require(serial = SecCertificateCopySerialNumber(request->certificate), errOut);
 307 #endif
 308
 309     ok &= SecDbPerformRead(this->db, &localError, ^(SecDbConnectionRef dbconn) {
 310         ok &= SecDbWithSQL(dbconn, selectHashAlgorithmSQL, &localError, ^bool(sqlite3_stmt *selectHash) {
 311             ok = SecDbBindBlob(selectHash, 1, CFDataGetBytePtr(serial), CFDataGetLength(serial), SQLITE_TRANSIENT, &localError);
 312             ok &= SecDbStep(dbconn, selectHash, &localError, ^(bool *stopHash) {
 313                 SecAsn1Oid algorithm;
 314                 algorithm.Data = (uint8_t *)sqlite3_column_blob(selectHash, 0);
 315                 algorithm.Length = sqlite3_column_bytes(selectHash, 0);
 316
 317                 /* Calculate the issuerKey and issuerName digests using the returned
 318                  hashAlgorithm. */
 319                 CFDataRef issuerNameHash = SecDigestCreate(kCFAllocatorDefault,
 320                                                            &algorithm, NULL, CFDataGetBytePtr(issuer), CFDataGetLength(issuer));
 321                 CFDataRef issuerPubKeyHash = SecDigestCreate(kCFAllocatorDefault,
 322                                                              &algorithm, NULL, publicKey->data, publicKey->length);
 323
 324                 if (issuerNameHash && issuerPubKeyHash && ok) ok &= SecDbWithSQL(dbconn, selectResponseSQL, &localError, ^bool(sqlite3_stmt *selectResponse) {
 325                     /* Now we have the serial, algorithm, issuerNameHash and
 326                      issuerPubKeyHash so let's lookup the db entry. */
 327                     if (ok) ok = SecDbBindDouble(selectResponse, 1, minInsertTime, &localError);
 328                     if (ok) ok = SecDbBindBlob(selectResponse, 2, CFDataGetBytePtr(issuerNameHash),
 329                                                CFDataGetLength(issuerNameHash), SQLITE_TRANSIENT, &localError);
 330                     if (ok) ok = SecDbBindBlob(selectResponse, 3, CFDataGetBytePtr(issuerPubKeyHash),
 331                                                CFDataGetLength(issuerPubKeyHash), SQLITE_TRANSIENT, &localError);
 332                     if (ok) ok = SecDbBindBlob(selectResponse, 4, CFDataGetBytePtr(serial),
 333                                                CFDataGetLength(serial), SQLITE_TRANSIENT, &localError);
 334                     if (ok) ok = SecDbBindBlob(selectResponse, 5, algorithm.Data,
 335                                                algorithm.Length, SQLITE_TRANSIENT, &localError);
 336                     if (ok) ok &= SecDbStep(dbconn, selectResponse, &localError, ^(bool *stopResponse) {
 337                         /* Found an entry! */
 338                         secdebug("ocspcache", "found cached response");
 339                         CFDataRef resp = CFDataCreate(kCFAllocatorDefault,
 340                                                       sqlite3_column_blob(selectResponse, 0),
 341                                                       sqlite3_column_bytes(selectResponse, 0));
 342                         sqlite3_int64 responseID = sqlite3_column_int64(selectResponse, 1);
 343                         if (resp) {
 344                             SecOCSPResponseRef new_response = SecOCSPResponseCreateWithID(resp, responseID);
 345                             if (response) {
 346                                 if (SecOCSPResponseProducedAt(response) < SecOCSPResponseProducedAt(new_response)) {
 347                                     SecOCSPResponseFinalize(response);
 348                                     response = new_response;
 349                                 } else {
 350                                     SecOCSPResponseFinalize(new_response);
 351                                 }
 352                             } else {
 353                                 response = new_response;
 354                             }
 355                             CFRelease(resp);
 356                         }
 357                     });
 358                     return ok;
 359                 });
 360
 361                 CFReleaseSafe(issuerNameHash);
 362                 CFReleaseSafe(issuerPubKeyHash);
 363             });
 364             return ok;
 365         });
 366     });
 367
 368 errOut:
 369     CFReleaseSafe(serial);
 370     CFReleaseSafe(issuer);
 371
 372     if (!ok) {
 373         secerror("ocsp cache lookup failed: %@", localError);
 374         if (response) {
 375             SecOCSPResponseFinalize(response);
 376             response = NULL;
 377         }
 378     }
 379     CFReleaseSafe(localError);
 380
 381     secdebug("ocspcache", "returning %s", (response ? "cached response" : "NULL"));
 382
 383     return response;
 384 }
 385
 386
 387 /* Public API */
 388
 389 void SecOCSPCacheReplaceResponse(SecOCSPResponseRef old_response, SecOCSPResponseRef response,
 390     CFURLRef localResponderURI, CFAbsoluteTime verifyTime) {
 391     SecOCSPCacheWith(^(SecOCSPCacheRef cache) {
 392         _SecOCSPCacheReplaceResponse(cache, old_response, response, localResponderURI, verifyTime);
 393     });
 394 }
 395
 396 SecOCSPResponseRef SecOCSPCacheCopyMatching(SecOCSPRequestRef request,
 397     CFURLRef localResponderURI /* may be NULL */) {
 398     __block SecOCSPResponseRef response = NULL;
 399     SecOCSPCacheWith(^(SecOCSPCacheRef cache) {
 400         response = _SecOCSPCacheCopyMatching(cache, request, localResponderURI, 0.0);
 401     });
 402     return response;
 403 }
 404
 405 SecOCSPResponseRef SecOCSPCacheCopyMatchingWithMinInsertTime(SecOCSPRequestRef request,
 406     CFURLRef localResponderURI, CFAbsoluteTime minInsertTime) {
 407     __block SecOCSPResponseRef response = NULL;
 408     SecOCSPCacheWith(^(SecOCSPCacheRef cache) {
 409         response = _SecOCSPCacheCopyMatching(cache, request, localResponderURI, minInsertTime);
 410     });
 411     return response;
 412 }