IOS ECC SecKeyCreateWithData Sec

IOS ECC 加密探索随笔：

//使用该方法无法用PEM格式公钥生成SecKeyRef 公钥，待解决。

+(SecKeyRef)getPublicKeyFromPem:(NSString*)key{

    // 下面是对于 PEM 格式的密钥文件的密钥多余信息的处理，通常 DER 不需要这一步

    //NSString *key = @"PEM 格式的密钥文件";

    NSRange spos;

    NSRange epos;

    //-----BEGIN PUBLIC KEY-----

    spos = [key rangeOfString:@"-----BEGIN RSA PRIVATE KEY-----"];

    if(spos.length > 0){

        epos = [key rangeOfString:@"-----END RSA PRIVATE KEY-----"];

    }else{

        spos = [key rangeOfString:@"-----BEGIN PUBLIC KEY-----"];

        epos = [key rangeOfString:@"-----END PUBLIC KEY-----"];

    }

    if(spos.location != NSNotFound && epos.location != NSNotFound){

        NSUInteger s = spos.location + spos.length;

        NSUInteger e = epos.location;

        NSRange range = NSMakeRange(s, e-s);

        key = [key substringWithRange:range];

    }

    key = [key stringByReplacingOccurrencesOfString:@"\r" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@"\n" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@"\t" withString:@""];

    key = [key stringByReplacingOccurrencesOfString:@" "  withString:@""];

    // This will be base64 encoded, decode it.

    //NSData *data = base64_decode(key);

    NSData *data = [UtilityHelper Base64Convert2Str:key]

    //NSData *data =[key dataUsingEncoding:NSUTF8StringEncoding];

    if(!data){

        return nil;

    }

    NSString * strtemp  =[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

    // 设置属性字典

    NSMutableDictionary *options = [NSMutableDictionary dictionary];

    //并尝试kSecAttrKeyTypeEC 也不行

    options[(__bridge id)kSecAttrKeyType] = (__bridge id) kSecAttrKeyTypeECSECPrimeRandom;

    options[(__bridge id)kSecAttrKeyClass] = (__bridge id) kSecAttrKeyClassPublic;

    NSNumber *size = @2048;

    options[(__bridge id)kSecAttrKeySizeInBits] = size;

    NSError *error = nil;

    CFErrorRef ee = (__bridge CFErrorRef)error;

    // 调用接口获取密钥对象

    SecKeyRef ret = SecKeyCreateWithData((__bridge CFDataRef)data, (__bridge CFDictionaryRef)options, &ee);

    if (error) {

        return nil;

    }

    return ret;

}

公钥PEM为：-----BEGIN PUBLIC KEY-----

MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE2+nDUyXeL6wAu5UAIIhdFdClJNdysydKysyozXtY

W3xXb6szLjA0FpV+mRcHWl+28cV4LxjqTEs+pEvu3bVzng==

-----END PUBLIC KEY-----

运行情况：