java - Objective C 等同于 Java 中的 MessageDigest？

Question

我正在执行将 Java 代码转换为 Objective C 的任务。

这是我必须转换的 Java 代码:

private String getHash(String input) 
{
    String ret = null;
    try 
    {
        MessageDigest md = MessageDigest.getInstance("SHA-256");

        byte[] bs = md.digest(input.getBytes("US-ASCII"));


        StringBuffer sb = new StringBuffer();
        for (byte b : bs) 
        {
            String bt = Integer.toHexString(b & 0xff);
            if(bt.length()==1) 
            {
                sb.append("0");
            }
            sb.append(bt);
        }
        ret = sb.toString();
    } 
    catch (Exception e) 
    {
    }
    return ret;
}

具体来说，我可以在与 MessageDigest class 具有相同功能的 Objective C 中使用什么？ ？

Answer 1

像这样:

#import <CommonCrypto/CommonDigest.h>

+(NSString*) sha256:(NSString *)input
{
    const char *s=[input cStringUsingEncoding:NSASCIIStringEncoding];
    NSData *keyData=[NSData dataWithBytes:s length:strlen(s)];

    uint8_t digest[CC_SHA256_DIGEST_LENGTH]={0};
    CC_SHA256(keyData.bytes, keyData.length, digest);
    NSData *out=[NSData dataWithBytes:digest length:CC_SHA256_DIGEST_LENGTH];
    NSString *hash=[out description];
    hash = [hash stringByReplacingOccurrencesOfString:@" " withString:@""];
    hash = [hash stringByReplacingOccurrencesOfString:@"<" withString:@""];
    hash = [hash stringByReplacingOccurrencesOfString:@">" withString:@""];
    return hash;
}