certificates/ota_cert_tool/ios_ota_cert_tool/PSUtilities.m

   1 //
   2 //  PSUtilities.m
   3 //  ios_ota_cert_tool
   4 //
   5 //  Created by James Murphy on 12/12/12.
   6 //  Copyright (c) 2012 James Murphy. All rights reserved.
   7 //
   8
   9 #import "PSUtilities.h"
  10 #import <Security/Security.h>
  11
  12 @implementation PSUtilities
  13
  14 + (void)outputError:(NSString *)message withError:(CFErrorRef)error
  15 {
  16         NSString* output = nil;
  17         if (nil != error)
  18         {
  19                 CFStringRef aCFStr = CFErrorCopyDescription(error);
  20                 if (NULL != aCFStr)
  21                 {
  22                         output = [NSString stringWithFormat:@"%@ error: %@", message, aCFStr];
  23                         CFRelease(aCFStr);
  24                 }
  25         }
  26
  27         if (nil == output)
  28         {
  29                 output = message;
  30         }
  31
  32         NSLog(@"%@",output);
  33         if (NULL != error)
  34         {
  35                 CFRelease(error);
  36         }
  37 }
  38
  39 + (NSString *)digestAndEncode:(CFDataRef)cfData useSHA1:(BOOL)useSHA1;
  40 {
  41     CFErrorRef cfError  = NULL;
  42     NSString* result = nil;
  43     CFTypeRef digestType = kSecDigestSHA2;
  44     CFIndex digestLength = 256;
  45
  46     if (useSHA1)
  47     {
  48         digestType = kSecDigestSHA1;
  49         digestLength = 0;
  50     }
  51
  52     SecTransformRef digestXForm = SecDigestTransformCreate(digestType, digestLength, &cfError);
  53     if (NULL != cfError)
  54     {
  55         CFRelease(cfData);
  56                 [PSUtilities outputError:@"Could not create the digesting transform." withError:cfError];
  57         return result;
  58     }
  59
  60         if (!SecTransformSetAttribute(digestXForm, kSecTransformInputAttributeName, cfData, &cfError))
  61     {
  62         CFRelease(cfData);
  63         CFRelease(digestXForm);
  64         [PSUtilities outputError:@"Could not set the input attribute" withError:cfError];
  65         return result;
  66     }
  67
  68     SecTransformRef base64Xform = SecEncodeTransformCreate(kSecBase64Encoding, &cfError);
  69
  70     if (NULL != cfError)
  71     {
  72         CFRelease(digestXForm);
  73                 [PSUtilities outputError:@"Could not create the encoding transform." withError:cfError];
  74         return result;
  75     }
  76
  77     SecGroupTransformRef groupXForm = SecTransformCreateGroupTransform();
  78     if (NULL == groupXForm)
  79     {
  80         CFRelease(digestXForm);
  81         CFRelease(base64Xform);
  82         NSLog(@"Could not create the group transform");
  83         return result;
  84     }
  85
  86     SecTransformConnectTransforms(digestXForm, kSecTransformOutputAttributeName,
  87                                   base64Xform, kSecTransformInputAttributeName,
  88                                   groupXForm, &cfError);
  89     CFRelease(digestXForm);
  90     CFRelease(base64Xform);
  91
  92     if (NULL != cfError)
  93     {
  94                 [PSUtilities outputError:@"Could not connect the transforms" withError:cfError];
  95         return result;
  96     }
  97
  98     CFDataRef cfResult = (CFDataRef)SecTransformExecute(groupXForm, &cfError);
  99     CFRelease(groupXForm);
 100     if (NULL != cfError)
 101     {
 102         [PSUtilities outputError:@"Could not execute the transform." withError:cfError];
 103         return result;
 104     }
 105     const void* pPtr = (const void*)CFDataGetBytePtr(cfResult);
 106     NSUInteger len = (NSUInteger)CFDataGetLength(cfResult);
 107
 108         NSData* temp_data = [[NSData alloc] initWithBytes:pPtr length:len];
 109         result = [[NSString alloc] initWithData:temp_data encoding:NSUTF8StringEncoding];
 110
 111     return result;
 112
 113 }
 114
 115 + (CFDataRef)readFile:(NSString *)file_path
 116 {
 117     CFDataRef result = NULL;
 118
 119     @autoreleasepool
 120     {
 121         NSError* error = nil;
 122
 123         if (nil == file_path)
 124         {
 125             NSLog(@"PSUtilities.readFile called with a nil file path");
 126             return result;
 127
 128         }
 129
 130         NSFileManager* fileManager = [NSFileManager defaultManager];
 131         BOOL isDir = NO;
 132         if (![fileManager fileExistsAtPath:file_path isDirectory:&isDir])
 133         {
 134             NSLog(@"PSUtilities.readFile %@ does not exist", file_path);
 135             return result;
 136         }
 137
 138         if (isDir)
 139         {
 140             NSLog(@"PSUtilities.readFile %@ does exist but it is a directory", file_path);
 141             return result;
 142         }
 143
 144
 145         NSData* temp_data = [NSData dataWithContentsOfFile:file_path options:0 error:&error];
 146         if (nil != error)
 147         {
 148             NSLog(@"NSData dataWithContentsOfFile returned error %@", file_path);
 149             return result;
 150         }
 151
 152         result = CFDataCreate(kCFAllocatorDefault, (const UInt8 *)[temp_data bytes], (CFIndex)[temp_data length]);
 153
 154     }
 155
 156     return result;
 157 }
 158
 159 + (SecCertificateRef)getCertificateFromData:(CFDataRef)data
 160 {
 161     SecCertificateRef result = NULL;
 162     SecExternalFormat inputFormat = kSecFormatUnknown;
 163     SecExternalItemType itemType = kSecItemTypeUnknown;
 164     SecItemImportExportFlags flags = 0;
 165     CFArrayRef outItems = NULL;
 166
 167     OSStatus err = SecKeychainItemImport(data, NULL, &inputFormat, &itemType, flags,
 168                                          NULL, NULL, &outItems);
 169     if (errSecSuccess != err)
 170     {
 171         NSLog(@"Could not import data");
 172     }
 173
 174     if (NULL != outItems)
 175     {
 176         CFIndex num_items = CFArrayGetCount(outItems);
 177         if (num_items > 0)
 178         {
 179             CFTypeRef anItem = (CFTypeRef)CFArrayGetValueAtIndex(outItems, 0);
 180             if (NULL != anItem && (CFGetTypeID(anItem) == SecCertificateGetTypeID()))
 181             {
 182                 result = (SecCertificateRef)anItem;
 183             }
 184         }
 185
 186         if (NULL != result)
 187         {
 188             CFRetain(result);
 189         }
 190         CFRelease(outItems);
 191     }
 192     return result;
 193 }
 194
 195 + (CFDataRef)getKeyDataFromCertificate:(SecCertificateRef)cert
 196 {
 197     CFDataRef result = NULL;
 198
 199     if (NULL == cert)
 200     {
 201         return result;
 202     }
 203
 204     SecKeyRef aPublicKey = NULL;
 205     OSStatus err = SecCertificateCopyPublicKey(cert, &aPublicKey);
 206     if (errSecSuccess == err && NULL != aPublicKey)
 207     {
 208         err = SecItemExport(aPublicKey, kSecFormatBSAFE, 0, NULL, &result);
 209         if (errSecSuccess != err)
 210         {
 211             result = NULL;
 212         }
 213         CFRelease(aPublicKey);
 214     }
 215     return result;
 216 }
 217
 218 + (SecKeyRef)getPrivateKeyWithName:(NSString *)keyName
 219 {
 220         SecKeyRef result = NULL;
 221         NSArray* key_array = [NSArray arrayWithObjects:kSecClass, kSecAttrLabel, kSecReturnRef, nil];
 222         NSArray* obj_array = [NSArray arrayWithObjects:kSecClassKey, keyName, kCFBooleanTrue, nil];
 223         NSDictionary* query = [NSDictionary dictionaryWithObjects:obj_array forKeys:key_array];
 224
 225         OSStatus err = SecItemCopyMatching(CFBridgingRetain(query), (CFTypeRef *)&result);
 226         if (errSecSuccess != err)
 227         {
 228                 NSLog(@"Unable to find the Private Key");
 229         }
 230         return result;
 231 }
 232
 233 + (NSString *)signAndEncode:(CFDataRef)data usingKey:(SecKeyRef)key useSHA1:(BOOL)useSHA1
 234 {
 235         NSString* result = nil;
 236         if (NULL == data || NULL == key)
 237         {
 238                 return result;
 239         }
 240
 241     CFTypeRef digestType = kSecDigestHMACSHA2;
 242     CFIndex digestLength = 256;
 243
 244     if (useSHA1)
 245     {
 246         digestType = kSecDigestSHA1;
 247         digestLength = 0;
 248     }
 249
 250         CFErrorRef error = NULL;
 251         SecTransformRef signXForm =  SecSignTransformCreate(key, &error);
 252         if (NULL != error)
 253         {
 254                 [PSUtilities outputError:@"Unable to create the signing transform" withError:error];
 255                 return result;
 256         }
 257
 258     if (!SecTransformSetAttribute(signXForm, kSecTransformInputAttributeName, data, &error))
 259     {
 260         CFRelease(signXForm);
 261                 [PSUtilities outputError:@"Could not set the input attribute" withError:error];
 262         return result;
 263     }
 264
 265         if (!SecTransformSetAttribute(signXForm, kSecDigestTypeAttribute, digestType, &error))
 266         {
 267                 CFRelease(signXForm);
 268                 [PSUtilities outputError:@"Unable to set the digest type attribute" withError:error];
 269                 return result;
 270         }
 271
 272     CFNumberRef digest_length_number  = CFNumberCreate(kCFAllocatorDefault, kCFNumberCFIndexType, &digestLength);
 273         if (!SecTransformSetAttribute(signXForm, kSecDigestLengthAttribute, digest_length_number, &error))
 274         {
 275                 CFRelease(signXForm);
 276         CFRelease(digest_length_number);
 277                 [PSUtilities outputError:@"Unable to set the digest length attribute" withError:error];
 278                 return result;
 279         }
 280     CFRelease(digest_length_number);
 281
 282         if (!SecTransformSetAttribute(signXForm, kSecInputIsAttributeName, kSecInputIsPlainText, &error))
 283         {
 284                 CFRelease(signXForm);
 285                 [PSUtilities outputError:@"Unable to set the is plain text attribute" withError:error];
 286                 return result;
 287         }
 288
 289         SecTransformRef base64Xform = SecEncodeTransformCreate(kSecBase64Encoding, &error);
 290     if (NULL != error)
 291     {
 292                 CFRelease(signXForm);
 293                 [PSUtilities outputError:@"Could not create the encoding transform." withError:error];
 294                 return result;
 295     }
 296
 297     SecGroupTransformRef groupXForm = SecTransformCreateGroupTransform();
 298     if (NULL == groupXForm)
 299     {
 300         CFRelease(signXForm);
 301         CFRelease(base64Xform);
 302         NSLog(@"Could not create the group transform");
 303         return result;
 304     }
 305
 306     SecTransformConnectTransforms(signXForm, kSecTransformOutputAttributeName,
 307                                   base64Xform, kSecTransformInputAttributeName,
 308                                   groupXForm, &error);
 309     CFRelease(signXForm);
 310     CFRelease(base64Xform);
 311         if (NULL != error)
 312     {
 313                 [PSUtilities outputError:@"Could connect the signing and encoding transforms." withError:error];
 314                 return result;
 315     }
 316
 317         CFDataRef cfResult = (CFDataRef)SecTransformExecute(groupXForm, &error);
 318     CFRelease(groupXForm);
 319     if (NULL != error)
 320     {
 321         [PSUtilities outputError:@"Could not execute the transform." withError:error];
 322         return result;
 323     }
 324     const void* pPtr = (const void*)CFDataGetBytePtr(cfResult);
 325     NSUInteger len = (NSUInteger)CFDataGetLength(cfResult);
 326
 327     NSData* temp_data = [[NSData alloc] initWithBytes:pPtr length:len];
 328     result = [[NSString alloc] initWithData:temp_data encoding:NSUTF8StringEncoding];
 329         return result;
 330 }
 331
 332
 333 @end