keychain/SecureObjectSync/SOSRingBackup.m

   1 //
   2 //  SOSRingBasic.c
   3 //  sec
   4 //
   5 //  Created by Richard Murphy on 3/3/15.
   6 //
   7 //
   8
   9 #include "SOSRingBackup.h"
  10
  11 #include <AssertMacros.h>
  12
  13 #include "keychain/SecureObjectSync/SOSInternal.h"
  14 #include "keychain/SecureObjectSync/SOSPeerInfoInternal.h"
  15 #include "keychain/SecureObjectSync/SOSPeerInfoCollections.h"
  16 #include "keychain/SecureObjectSync/SOSCircle.h"
  17 #include <Security/SecureObjectSync/SOSViews.h>
  18 #include <Security/SecFramework.h>
  19
  20 #include <Security/SecKey.h>
  21 #include <Security/SecKeyPriv.h>
  22 #include <CoreFoundation/CoreFoundation.h>
  23
  24 #include <utilities/SecCFWrappers.h>
  25
  26 #include <stdlib.h>
  27
  28 #include "SOSRingUtils.h"
  29 #include "SOSRingTypes.h"
  30 #include "SOSRingBasic.h"
  31
  32 // MARK: Backup Ring Ops
  33
  34 static SOSRingRef SOSRingCreate_Backup(CFStringRef name, CFStringRef myPeerID, CFErrorRef *error) {
  35     return SOSRingCreate_ForType(name, kSOSRingBackup, myPeerID, error);
  36 }
  37
  38
  39 // Make sure all the peers in the ring have access to the ring views
  40 static bool SOSBackupRingPeersInViews(CFSetRef peers, SOSRingRef ring) {
  41     CFSetRef ringViews = SOSBackupRingGetViews(ring, NULL);
  42     if(!ringViews) return false;
  43     __block bool retval = true;
  44     SOSRingForEachPeerID(ring, ^(CFStringRef peerID) {
  45         SOSPeerInfoRef peerInfo = SOSPeerInfoSetFindByID(peers, peerID);
  46         if(peerInfo) {
  47             CFSetForEach(ringViews, ^(const void *value) {
  48                 if(!SOSPeerInfoIsViewPermitted(peerInfo, (CFStringRef) value)) retval = false;
  49             });
  50         } else {
  51             retval = false;
  52         }
  53     });
  54     return retval;
  55 }
  56
  57 // Make sure that the ring includes me if I'm enabled for its view.
  58 static SOSConcordanceStatus SOSBackupRingEvaluateMyInclusion(SOSRingRef ring, SOSFullPeerInfoRef me) {
  59     bool shouldBeInRing = false;
  60     bool amInThisRing = false;
  61
  62     if (me) {
  63         SOSPeerInfoRef pi = SOSFullPeerInfoGetPeerInfo(me);
  64         CFStringRef peerID = SOSPeerInfoGetPeerID(pi);
  65         CFSetRef ringViews = SOSRingGetBackupViewset_Internal(ring);
  66         CFSetRef piViews = SOSPeerInfoGetPermittedViews(pi);
  67         shouldBeInRing = CFSetIsSubset(ringViews, piViews);
  68         amInThisRing = SOSRingHasPeerWithID(ring, peerID, NULL);
  69     }
  70
  71     if(shouldBeInRing && !amInThisRing) return kSOSConcordanceMissingMe;
  72     if(!shouldBeInRing && amInThisRing) return kSOSConcordanceImNotWorthy;
  73     return kSOSConcordanceTrusted;
  74 }
  75
  76 static SOSConcordanceStatus SOSRingPeerKeyConcordanceTrust_Backup(SOSFullPeerInfoRef me, CFSetRef peers, SOSRingRef knownRing, SOSRingRef proposedRing,
  77                                                     __unused SecKeyRef knownPubkey, SecKeyRef userPubkey,
  78                                                     CFStringRef excludePeerID, CFErrorRef *error) {
  79     if(userPubkey == NULL) {
  80         SOSCreateError(kSOSErrorPublicKeyAbsent, CFSTR("Concordance with no public key - need to validate application"), NULL, error);
  81         return kSOSConcordanceNoUserKey;
  82     }
  83
  84     if(SOSRingIsOlderGeneration(proposedRing, knownRing)) {
  85         SOSCreateError(kSOSErrorReplay, CFSTR("Bad generation"), NULL, error);
  86         return kSOSConcordanceGenOld;
  87     }
  88
  89
  90     if (SOSRingIsEmpty_Internal(proposedRing)) {
  91         return kSOSConcordanceTrusted;
  92     }
  93
  94     SOSConcordanceStatus localstatus = SOSBackupRingEvaluateMyInclusion(proposedRing, me);
  95     if(localstatus == kSOSConcordanceMissingMe) {
  96         SOSCreateError(kSOSErrorReplay, CFSTR("Improper exclusion of this peer"), NULL, error);
  97         return localstatus;
  98     }
  99
 100     if(localstatus == kSOSConcordanceImNotWorthy) {
 101         SOSCreateError(kSOSErrorReplay, CFSTR("Improper inclusion of this peer"), NULL, error);
 102         return localstatus;
 103     }
 104
 105     if(!SOSBackupRingPeersInViews(peers, proposedRing)) {
 106         return kSOSConcordanceInvalidMembership;
 107     }
 108
 109     return GetSignersStatus_Transitive(peers, knownRing, proposedRing, userPubkey, excludePeerID, error);
 110 }
 111
 112 bool SOSBackupRingSetViews(SOSRingRef ring, SOSFullPeerInfoRef requestor, CFSetRef viewSet, CFErrorRef *error) {
 113     CFStringRef myPeerID = SOSPeerInfoGetPeerID(SOSFullPeerInfoGetPeerInfo(requestor));
 114     SecKeyRef priv = SOSFullPeerInfoCopyDeviceKey(requestor, error);
 115     bool retval = priv && myPeerID &&
 116     SOSRingSetLastModifier(ring, myPeerID) &&
 117     SOSRingSetBackupViewset_Internal(ring, viewSet) &&
 118     SOSRingGenerationSign_Internal(ring, priv, error);
 119     CFReleaseNull(priv);
 120     return retval;
 121 }
 122
 123 CFSetRef SOSBackupRingGetViews(SOSRingRef ring, CFErrorRef *error) {
 124     return SOSRingGetBackupViewset_Internal(ring);
 125 }
 126
 127 ringFuncStruct backup = {
 128     "Backup",
 129     1,
 130     SOSRingCreate_Backup,
 131     SOSRingResetToEmpty_Basic,
 132     SOSRingResetToOffering_Basic,
 133     SOSRingDeviceIsInRing_Basic,
 134     SOSRingApply_Basic,
 135     SOSRingWithdraw_Basic,
 136     SOSRingGenerationSign_Basic,
 137     SOSRingConcordanceSign_Basic,
 138     SOSRingPeerKeyConcordanceTrust_Backup,
 139     NULL,
 140     NULL,
 141     SOSRingSetPayload_Basic,
 142     SOSRingGetPayload_Basic,
 143 };