我对 RSA 加密和 Base 64 编码文本解密有疑问。当我直接解密加密文本（unsigned char *）时，一切正常，我得到正确的结果。但是当我进行 base64 编码时，openssl 无法解密数据，尽管 base64 解码的数据与加密数据完全相同：
例如（第一个是加密结果和第二个base 64解码结果。直接解码第一个char *效果很好。）
加密 - ßÁ¨£®Òz>Ô‹n.€Ö∫BÔ–∂ü∏ÕD⁄UÖáµ)ûKufi wÆ&_è”eëõ~gK∂¶$kŸƒ∫ª`ÔfΩ˙˛{∆_MªÔëbP Q¶FL±Ü;! ü•◊s>ħΔ◊⁄≤ò˙ˇCWôVÂzôzíö≤ÙU¶?⁄l[*H?o\ñ>ƒ<'4mœ“Lr Íhh
解码字符串 - ßÁ¨£®Òz>Ô‹n.€Ö∫BÔ–∂ü∏ÕD⁄UÖáµ)ûKufi wÆ&_è”eëõ~gK∂¶$kŸƒ∫ª`ÔfΩ˙˛{∆_MªÔëbP Q¶FL±Ü; !ü•◊s>ħΔ◊⁄≤ò˙ˇCWôVÂzôzíö≤ÙU¶?⁄l[*H?o\ñ>ƒ<'4mœ“Lr Íhh
代码：
+(NSString *) rsaEncryptedStringFromText: (NSString *) text
{
const char *message = [text UTF8String];
NSLog(@"message - %s", message);
int bufSize;
NSString *keyFilePath = [[NSBundle mainBundle] pathForResource:@"publicKey" ofType:@"pem"];
FILE *keyfile = fopen([keyFilePath UTF8String], "r");
RSA *rsa = PEM_read_RSA_PUBKEY(keyfile, NULL, NULL, NULL);
if (rsa == NULL)
{
return nil;
}
int key_size = RSA_size(rsa);
unsigned char *encrypted = (unsigned char *) malloc(key_size);
bufSize = RSA_public_encrypt(strlen(message), (unsigned char *) message, encrypted, rsa, RSA_PKCS1_PADDING);
if (bufSize == -1)
{
RSA_free(rsa);
return nil;
}
NSLog(@"encrypted - %s", encrypted);
NSData *encryptedData = [NSData dataWithBytes:encrypted length:strlen((const char *)encrypted)];
NSString *base64 = [encryptedData base64Encoding];
RSA_free(rsa);
return base64;
}
+(NSString *) rsaDecryptToStringFromText: (NSString *) text
{
//NSLog(@"text - %@", text);
NSData *decodedData = [NSData dataWithBase64EncodedString: text];
unsigned char* message = (unsigned char*) [decodedData bytes];
NSLog(@"decoded string - %s", message);
RSA *privKey = NULL;
FILE *priv_key_file;
unsigned char *ptext;
NSString *keyFilePath = [[NSBundle mainBundle] pathForResource:@"privateKeyPair" ofType:@"pem"];
priv_key_file = fopen([keyFilePath UTF8String], "rb");
ERR_print_errors_fp(priv_key_file);
privKey = PEM_read_RSAPrivateKey(priv_key_file, NULL, NULL, NULL);
int key_size = RSA_size(privKey);
ptext = malloc(key_size);
int outlen = RSA_private_decrypt(key_size, (const unsigned char*)message, ptext, privKey, RSA_PKCS1_PADDING);
if(outlen < 0) return nil;
RSA_free(privKey);
return [NSString stringWithUTF8String: (const char *)ptext];
}
Base 64 编码-解码是这样完成的：
http://www.iphonedevsdk.com/forum/iphone-sdk-development/21689-base-64-string-help.html#post98080