sec/SOSCircle/SecureObjectSync/SOSInternal.c

   1 //
   2 //  SOSInternal.c
   3 //  sec
   4 //
   5 //  Created by Mitch Adler on 7/18/12.
   6 //
   7 //
   8
   9 #include <SecureObjectSync/SOSInternal.h>
  10 #include <SecureObjectSync/SOSCircle.h>
  11 #include <SecureObjectSync/SOSCloudCircle.h>
  12 #include <SecureObjectSync/SOSAccount.h>
  13
  14 #include "utilities/SecCFError.h"
  15 #include "utilities/SecCFRelease.h"
  16 #include "utilities/SecCFWrappers.h"
  17 #include "utilities/iOSforOSX.h"
  18
  19 #include <CoreFoundation/CoreFoundation.h>
  20
  21 #include <Security/SecKey.h>
  22 #include <Security/SecKeyPriv.h>
  23 #include <Security/SecItem.h>
  24 #include <securityd/SecDbItem.h> // For SecError
  25 #include "utilities/iOSforOSX.h"
  26
  27 #include <Security/SecBase64.h>
  28
  29 #include <AssertMacros.h>
  30
  31 CFStringRef kSOSErrorDomain = CFSTR("com.apple.security.sos.error");
  32
  33 bool SOSCreateError(CFIndex errorCode, CFStringRef descriptionString, CFErrorRef previousError, CFErrorRef *newError) {
  34     SOSCreateErrorWithFormat(errorCode, previousError, newError, NULL, CFSTR("%@"), descriptionString);
  35     return true;
  36 }
  37
  38 bool SOSCreateErrorWithFormat(CFIndex errorCode, CFErrorRef previousError, CFErrorRef *newError,
  39                               CFDictionaryRef formatOptions, CFStringRef format, ...) {
  40     va_list va;
  41     va_start(va, format);
  42     bool res = SOSCreateErrorWithFormatAndArguments(errorCode, previousError, newError, formatOptions, format, va);
  43     va_end(va);
  44     return res;
  45 }
  46
  47 bool SOSCreateErrorWithFormatAndArguments(CFIndex errorCode, CFErrorRef previousError, CFErrorRef *newError,
  48                                           CFDictionaryRef formatOptions, CFStringRef format, va_list args)
  49 {
  50     SecCFCreateErrorWithFormatAndArguments(errorCode, kSOSErrorDomain, previousError, newError, formatOptions, format, args);
  51     return true;
  52 }
  53
  54
  55 //
  56 // Utility Functions
  57 //
  58
  59 static OSStatus GenerateECPairImp(int keySize, CFBooleanRef permanent, SecKeyRef* public, SecKeyRef *full)
  60 {
  61     static const CFStringRef sTempNameToUse = CFSTR("GenerateECPair Temporary Key - Shouldn't be live");
  62
  63     CFNumberRef signing_bitsize = CFNumberCreate(kCFAllocatorDefault, kCFNumberIntType, &keySize);
  64
  65     CFDictionaryRef keygen_parameters = CFDictionaryCreateForCFTypes(kCFAllocatorDefault,
  66                                                                      kSecAttrKeyType,       kSecAttrKeyTypeEC,
  67                                                                      kSecAttrKeySizeInBits, signing_bitsize,
  68                                                                      kSecAttrIsPermanent,   permanent,
  69                                                                      kSecAttrLabel,         sTempNameToUse,
  70                                                                      NULL);
  71     CFReleaseNull(signing_bitsize);
  72     OSStatus result = SecKeyGeneratePair(keygen_parameters, public, full);
  73     CFReleaseNull(keygen_parameters);
  74
  75     return result;
  76 }
  77
  78 OSStatus GenerateECPair(int keySize, SecKeyRef* public, SecKeyRef *full)
  79 {
  80     return GenerateECPairImp(keySize, kCFBooleanFalse, public, full);
  81 }
  82
  83 OSStatus GeneratePermanentECPair(int keySize, SecKeyRef* public, SecKeyRef *full)
  84 {
  85     return GenerateECPairImp(keySize, kCFBooleanTrue, public, full);
  86 }
  87
  88 static CFStringRef SOSCircleCopyDescriptionFromData(CFDataRef data)
  89 {
  90     CFErrorRef error;
  91     CFStringRef result = NULL;
  92
  93     SOSCircleRef circle = SOSCircleCreateFromData(kCFAllocatorDefault, data, &error);
  94
  95     if (circle)
  96         result = CFStringCreateWithFormat(kCFAllocatorDefault, NULL, CFSTR("%@"), circle);
  97
  98     CFReleaseSafe(circle);
  99
 100     return result;
 101 }
 102
 103 CFStringRef SOSChangesCopyDescription(CFDictionaryRef changes, bool is_sender)
 104 {
 105     CFMutableStringRef string = CFStringCreateMutableCopy(kCFAllocatorDefault, 0, CFSTR("<Changes: {\n"));
 106
 107     CFDictionaryForEach(changes, ^(const void *key, const void *value) {
 108         CFStringRef value_description = NULL;
 109         if (isString(key) && isData(value)) {
 110             CFDataRef value_data = (CFDataRef) value;
 111             switch (SOSKVSKeyGetKeyType(key)) {
 112                 case kCircleKey:
 113                     value_description = SOSCircleCopyDescriptionFromData(value_data);
 114                     break;
 115                 case kMessageKey:
 116                     value_description = SOSMessageCopyDescription(value_data);
 117                     break;
 118                 default:
 119                     break;
 120             }
 121
 122         }
 123         CFStringAppendFormat(string, NULL, CFSTR("    '%@' %s %@\n"),
 124                              key,
 125                              is_sender ? "<=" : "=>",
 126                              value_description ? value_description : value);
 127
 128         CFReleaseNull(value_description);
 129     });
 130
 131     CFStringAppendFormat(string, NULL, CFSTR("}"));
 132
 133     return string;
 134 }
 135
 136 CFStringRef SOSCopyIDOfKey(SecKeyRef key, CFErrorRef *error)
 137 {
 138     const struct ccdigest_info * di = ccsha1_di();
 139     CFDataRef publicBytes = NULL;
 140     CFStringRef result = NULL;
 141
 142     uint8_t digest[di->output_size];
 143     char encoded[2 * di->output_size]; // Big enough for base64 encoding.
 144
 145     require_quiet(SecError(SecKeyCopyPublicBytes(key, &publicBytes), error, CFSTR("Failed to export public bytes %@"), key), fail);
 146
 147     ccdigest(di, CFDataGetLength(publicBytes), CFDataGetBytePtr(publicBytes), digest);
 148
 149     size_t length = SecBase64Encode(digest, sizeof(digest), encoded, sizeof(encoded));
 150     assert(length && length < sizeof(encoded));
 151     if (length > 26)
 152       length = 26;
 153     encoded[length] = 0;
 154     CFReleaseNull(publicBytes);
 155     return CFStringCreateWithCString(kCFAllocatorDefault, encoded, kCFStringEncodingASCII);
 156
 157 fail:
 158     CFReleaseNull(publicBytes);
 159     return result;
 160 }