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