OSX/libsecurity_utilities/lib/CSPDLTransaction.cpp

   1 /*
   2  * Copyright (c) 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 #include "CSPDLTransaction.h"
  25 #include <Security/SecBasePriv.h>
  26 #include <syslog.h>
  27
  28 DLTransaction::DLTransaction(CSSM_DL_DB_HANDLE dldbh)
  29     : mDldbh(dldbh), mSuccess(false), mFinalized(false), mAutoCommit(CSSM_TRUE) {
  30     initialize();
  31 }
  32
  33 DLTransaction::DLTransaction()
  34     : mSuccess(false), mFinalized(false), mAutoCommit(CSSM_TRUE) {
  35 }
  36
  37 void DLTransaction::initialize() {
  38     // Turn off autocommit on the underlying DL and remember the old state.
  39     Security::CssmClient::ObjectImpl::check(CSSM_DL_PassThrough(mDldbh,
  40                 CSSM_APPLEFILEDL_TOGGLE_AUTOCOMMIT,
  41                 NULL, reinterpret_cast<void **>(&mAutoCommit)));
  42 }
  43
  44 DLTransaction::~DLTransaction() {
  45     finalize();
  46 }
  47
  48 void DLTransaction::commit() {
  49     // Commit the transaction, and throw if it fails
  50
  51     // If autocommit wasn't on on the database when we started, don't
  52     // actually commit. There might be something else going on...
  53     if(mAutoCommit) {
  54         Security::CssmClient::ObjectImpl::check(CSSM_DL_PassThrough(mDldbh, CSSM_APPLEFILEDL_COMMIT, NULL, NULL));
  55         CSSM_DL_PassThrough(mDldbh, CSSM_APPLEFILEDL_TOGGLE_AUTOCOMMIT, reinterpret_cast<const void *>(mAutoCommit), NULL);
  56     }
  57
  58     // Throwing above means this wasn't a success and we're not finalized. On exit, we'll roll back the transaction.
  59     mSuccess = true;
  60     mFinalized = true;
  61 }
  62
  63 void DLTransaction::rollback() {
  64     // If autocommit wasn't on on the database when we started, don't
  65     // actually roll back. There might be something else going on...
  66     if(mAutoCommit) {
  67         CSSM_DL_PassThrough(mDldbh, CSSM_APPLEFILEDL_ROLLBACK, NULL, NULL);
  68         CSSM_DL_PassThrough(mDldbh, CSSM_APPLEFILEDL_TOGGLE_AUTOCOMMIT,
  69                             reinterpret_cast<const void *>(mAutoCommit), NULL);
  70     }
  71 }
  72
  73 void DLTransaction::finalize() {
  74     if(mFinalized) {
  75         return;
  76     }
  77
  78     // if this transaction was not a success, roll back.
  79     if(!mSuccess) {
  80         // Note that we're likely (but not necessarily) unwinding the stack for an exception right now.
  81         // (If this transaction succeeded, we wouldn't be here. So, it failed, and this code likes to fail with exceptions.)
  82         // If this throws an exception, we might crash the whole process.
  83         // Swallow exceptions whole, but log them aggressively.
  84         try {
  85             rollback();
  86         } catch(CssmError cssme) {
  87             const char* errStr = cssmErrorString(cssme.error);
  88             secnotice("integrity", "caught CssmError during transaction rollback: %d %s", (int) cssme.error, errStr);
  89             syslog(LOG_ERR, "ERROR: failed to rollback keychain transaction: %d %s", (int) cssme.error, errStr);
  90         }
  91     }
  92     mFinalized = true;
  93 }
  94
  95
  96 CSPDLTransaction::CSPDLTransaction(Security::CssmClient::Db& db)
  97     : DLTransaction(), mDb(db) {
  98     // Get the handle of the DL underlying this CSPDL.
  99     mDb->passThrough(CSSM_APPLECSPDL_DB_GET_HANDLE, NULL,
 100             reinterpret_cast<void **>(&mDldbh));
 101
 102     initialize();
 103 }
 104
 105 CSPDLTransaction::~CSPDLTransaction() {
 106 }
 107