私はRSAアルゴリズムを実装しようとしていますが、アップルのリファレンスに従いました。しかし、uint8_tをNSData、NSStringに変換する際に問題が発生します。
私はこれまでにこれを行いました。これらの関数は参照で定義されています
-(void)test{
[self generateKeyPairPlease];
NSData *data = [self encryptWithPublicKey]; //All goes well until here
[self decryptWithPrivateKey:data];
}
暗号化のために私はしました。
- (NSData *)encryptWithPublicKey
{
OSStatus status = noErr;
size_t cipherBufferSize;
uint8_t *cipherBuffer; // 1
// [cipherBufferSize]
const uint8_t dataToEncrypt[] = "the quick brown fox jumps "
"over the lazy dog\0"; // 2
size_t dataLength = sizeof(dataToEncrypt)/sizeof(dataToEncrypt[0]);
SecKeyRef publicKey = NULL; // 3
NSData * publicTag = [NSData dataWithBytes:publicKeyIdentifier
length:strlen((const char *)publicKeyIdentifier)]; // 4
NSMutableDictionary *queryPublicKey =
[[NSMutableDictionary alloc] init]; // 5
[queryPublicKey setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass];
[queryPublicKey setObject:publicTag forKey:(__bridge id)kSecAttrApplicationTag];
[queryPublicKey setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];
[queryPublicKey setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnRef];
// 6
status = SecItemCopyMatching
((__bridge CFDictionaryRef)queryPublicKey, (CFTypeRef *)&publicKey); // 7
// Allocate a buffer
cipherBufferSize = SecKeyGetBlockSize(publicKey);
cipherBuffer = malloc(cipherBufferSize);
// Error handling
if (cipherBufferSize < sizeof(dataToEncrypt)) {
// Ordinarily, you would split the data up into blocks
// equal to cipherBufferSize, with the last block being
// shorter. For simplicity, this example assumes that
// the data is short enough to fit.
printf("Could not decrypt. Packet too large.\n");
return NULL;
}
// Encrypt using the public.
status = SecKeyEncrypt( publicKey,
kSecPaddingPKCS1,
dataToEncrypt,
(size_t) dataLength,
cipherBuffer,
&cipherBufferSize
); // 8
// Error handling
// Store or transmit the encrypted text
if (publicKey) CFRelease(publicKey);
NSData *encryptedData = [NSData dataWithBytes:cipherBuffer length:dataLength];
free(cipherBuffer);
return encryptedData;
}
しかし、（復号化された結果）をdecryptWithPrivateKeyに変換できません 。最初に、印刷時にバイトを正しく表示して変換しようとしましたが、文字列に変換されていません。uint8_t *plainBufferNSStringNSDataNSLogNSData
- (void)decryptWithPrivateKey: (NSData *)dataToDecrypt
{
OSStatus status = noErr;
size_t cipherBufferSize = [dataToDecrypt length];
uint8_t *cipherBuffer = (uint8_t *)[dataToDecrypt bytes];
size_t plainBufferSize;
uint8_t *plainBuffer;
SecKeyRef privateKey = NULL;
NSData * privateTag = [NSData dataWithBytes:privateKeyIdentifier
length:strlen((const char *)privateKeyIdentifier)];
NSMutableDictionary *queryPrivateKey = [[NSMutableDictionary alloc] init];
// Set the private key query dictionary.
[queryPrivateKey setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass];
[queryPrivateKey setObject:privateTag forKey:(__bridge id)kSecAttrApplicationTag];
[queryPrivateKey setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];
[queryPrivateKey setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnRef];
// 1
status = SecItemCopyMatching
((__bridge CFDictionaryRef)queryPrivateKey, (CFTypeRef *)&privateKey); // 2
// Allocate the buffer
plainBufferSize = SecKeyGetBlockSize(privateKey);
plainBuffer = malloc(plainBufferSize);
if (plainBufferSize < cipherBufferSize) {
// Ordinarily, you would split the data up into blocks
// equal to plainBufferSize, with the last block being
// shorter. For simplicity, this example assumes that
// the data is short enough to fit.
printf("Could not decrypt. Packet too large.\n");
return;
}
// Error handling
status = SecKeyDecrypt( privateKey,
kSecPaddingPKCS1,
cipherBuffer,
cipherBufferSize,
plainBuffer,
&plainBufferSize
); // 3
//*******************************************************************************
// Not able to convert uint8_t *plainBuffer to string
// I also tried to convert it into NSData and then try to convert it into NSString but can't
//What Should i do here to get string back
if(privateKey) CFRelease(privateKey);
}
@end
uint8_t plainBuffer復号化された結果をNSDataに、NSStringまたは単にNSString文字列を取り戻すために変換する方法を知りたいです。暗号化とキー生成コードについては、このリファレンスを参照してください。
前もって感謝します..