OSX/sec/SOSCircle/SecureObjectSync/SOSPeerCoder.c

   1 /*
   2  * Copyright (c) 2012-2016 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 <Security/SecureObjectSync/SOSPeer.h>
  25 #include <Security/SecureObjectSync/SOSPeerCoder.h>
  26 #include <Security/SecureObjectSync/SOSTransportMessage.h>
  27 #include <Security/SecureObjectSync/SOSCoder.h>
  28 #include <Security/SecureObjectSync/SOSAccount.h>
  29 #include <Security/SecureObjectSync/SOSEngine.h>
  30 #include <Security/SecureObjectSync/SOSEnginePriv.h>
  31
  32 #include <utilities/debugging.h>
  33 #include <utilities/SecCFWrappers.h>
  34
  35 #include <AssertMacros.h>
  36 #include "SOSInternal.h"
  37
  38 void SOSPeerCoderConsume(SOSEnginePeerMessageSentBlock *sent, bool ok) {
  39     if (*sent)
  40         (*sent)(ok);
  41 }
  42
  43 enum SOSCoderUnwrapStatus SOSPeerHandleCoderMessage(SOSPeerRef peer, SOSCoderRef coder, CFStringRef peer_id, CFDataRef codedMessage, CFDataRef *decodedMessage, bool *forceSave, CFErrorRef *error) {
  44
  45     enum SOSCoderUnwrapStatus result = SOSCoderUnwrapError;
  46     CFMutableDataRef localDecodedMessage = NULL;
  47
  48     SOSCoderStatus coderStatus = kSOSCoderDataReturned;
  49     require_action_quiet(coder, xit, secerror("%@ getCoder: %@", peer_id, error ? *error : NULL));
  50     CFErrorRef localError = NULL;
  51     if (coder) {
  52         coderStatus = SOSCoderUnwrap(coder, codedMessage, &localDecodedMessage, peer_id, error);
  53
  54         switch(coderStatus) {
  55             case kSOSCoderDataReturned: {
  56                 logRawMessage(localDecodedMessage, false, 0);
  57                 result = SOSCoderUnwrapDecoded;
  58                 break;
  59             }
  60             case kSOSCoderNegotiating:  // Sent message already in Unwrap.
  61                 result = SOSCoderUnwrapHandled;
  62                 secnotice("engine", "%@ engine negotiating", peer_id);
  63                 break;
  64             case kSOSCoderNegotiationCompleted:
  65                 SOSPeerDidConnect(peer);
  66                 result = SOSCoderUnwrapHandled;
  67                 *forceSave = true;
  68                 secnotice("engine", "%@ engine negotiation complete", peer_id);
  69                 break;
  70             case kSOSCoderFailure:      // Probably restart coder
  71                 secnotice("engine", "%@ engine failed handling message %@", peer_id, error ? *error : NULL);
  72                 SOSCoderReset(coder);
  73                 if(SOSCoderStart(coder, &localError) == kSOSCoderFailure){
  74                     secerror("Attempt to recover coder failed to restart: %@", localError);
  75                 }
  76                 break;
  77             case kSOSCoderStaleEvent:   // We received an event we have already processed in the past.
  78                 secinfo("engine", "%@ engine stale event ignored", peer_id);
  79                 result = SOSCoderUnwrapHandled;
  80                 break;
  81             case kSOSCoderForceMessage:
  82                 SOSPeerSetMustSendMessage(peer, true);
  83                 result = SOSCoderUnwrapHandled;
  84                 break;
  85             case kSOSCoderTooNew:       // We received an event from the future!
  86                 secnotice("engine", "%@ engine received a message too soon, time to restart", peer_id);
  87                 SOSCoderReset(coder);
  88                 if(SOSCoderStart(coder, &localError) == kSOSCoderFailure){
  89                     secerror("Attempt to recover coder failed to restart: %@", localError);
  90                 }
  91                 break;
  92             default:
  93                 assert(false);
  94                 break;
  95         }
  96         if(decodedMessage)
  97             *decodedMessage = CFRetainSafe(localDecodedMessage);
  98         CFReleaseNull(localDecodedMessage);
  99     }
 100
 101     CFReleaseNull(localError);
 102 xit:
 103     return result;
 104 }
 105
 106
 107 bool SOSPeerCoderSendMessageIfNeeded(SOSEngineRef engine, SOSTransactionRef txn, SOSPeerRef peer, SOSCoderRef coder, CFDataRef *message_to_send, CFStringRef peer_id, SOSEnginePeerMessageSentBlock *sent, CFErrorRef *error) {
 108     bool ok = false;
 109     secnotice("transport", "coder state: %@", coder);
 110     require_action_quiet(coder, xit, secerror("%@ getCoder: %@", peer_id, error ? *error : NULL));
 111
 112     if (SOSCoderCanWrap(coder)) {
 113         secinfo("transport", "%@ Coder can wrap, getting message from engine", peer_id);
 114         CFMutableDataRef codedMessage = NULL;
 115         CFDataRef message = SOSEngineCreateMessage_locked(engine, txn, peer, error, sent);
 116         if (!message) {
 117             secnotice("transport", "%@ SOSEngineCreateMessageToSyncToPeer failed: %@", peer_id, *error);
 118         } else if (CFDataGetLength(message) || SOSPeerMustSendMessage(peer)) {
 119             // TODO: Remove SOSPeerMustSendMessage from peer and move into coder/transport instead
 120             ok = message && (SOSCoderWrap(coder, message, &codedMessage, peer_id, error) == kSOSCoderDataReturned);
 121             if (!ok) {
 122                 secnotice("transport", "%@ SOSCoderWrap failed: %@", peer_id, *error);
 123             } else {
 124                 CFRetainAssign(*message_to_send, codedMessage);
 125                 engine->codersNeedSaving = true;
 126             }
 127             CFReleaseNull(codedMessage);
 128         } else {
 129             // Zero length message means we have no work to do.
 130             ok = true;
 131         }
 132         CFReleaseNull(message);
 133     } else {
 134         *message_to_send = SOSCoderCopyPendingResponse(coder);
 135         engine->codersNeedSaving = true;
 136         secinfo("transport", "%@ negotiating, %@", peer_id, (message_to_send && *message_to_send) ? CFSTR("sending negotiation message.") : CFSTR("waiting for negotiation message."));
 137         *sent = Block_copy(^(bool wasSent){
 138             if (wasSent)
 139                 SOSCoderConsumeResponse(coder);
 140         });
 141         ok = true;
 142     }
 143
 144 xit:
 145     return ok;
 146 }