RSA 用Security.framwork解密问题
我用RSA的public key来解密，php那边用private key来加密，用的Security.framework来解密。但是解出来的数据前面多了一小串奇怪的乱码，后面数据是正确的。谁能帮我看看哪里有问题？
- (NSData *)decryptToDataWithPublicKey: (NSData *)dataToDecrypt
{
NSData *wrappedSymmetricKey = dataToDecrypt;
SecKeyRef key = self.publicKey;//这是之前已经成功使用的SecKeyRef
size_t cipherBufferSize = SecKeyGetBlockSize(key);
size_t keyBufferSize = [wrappedSymmetricKey length];
NSMutableData *bits = [NSMutableData dataWithLength:keyBufferSize];
__unused OSStatus sanityCheck = SecKeyDecrypt(key,
kSecPaddingNone,
(const uint8_t *) [wrappedSymmetricKey bytes],
cipherBufferSize,
[bits mutableBytes],
&keyBufferSize);
[bits setLength:keyBufferSize];
return [bits copy];
}
最后的数据前面多了一堆fffff，不知道哪里出了问题..
f结束后的数据是正确的。
撸管强力3连发
9 years, 2 months ago
Answers
自问自答吧。最后这个方法还是没有找到解决方案，最后弃用了
Security.framework
，而是利用OC兼容C的特性，倒入openssl的framework，用openssl的函数解密。
- (NSString *)decryptToDataWithPublicKey: (NSString *)dataToDecrypt
{
NSData *contentData = [dataToDecrypt base64DecodedData];
unsigned char *decrypted = (unsigned char *)malloc(rsa_public_len - 1);
char *err = NULL;
if (RSA_public_decrypt([contentData length], [contentData bytes], decrypted, rsa_publicKey, RSA_NO_PADDING) == -1) {
ERR_load_CRYPTO_strings();
fprintf(stderr, "Error %s\n", ERR_error_string(ERR_get_error(), err));
fprintf(stderr, "Error %s\n", err);
return nil;
}
RSA_free(rsa_publicKey);
NSString *str = [NSString stringWithUTF8String:(char *) decrypted];
return str;
}
我只是扎古而已
answered 9 years, 2 months ago