如何在C/C++ / Objective-C中计算X.509证书的SHA-1指纹？

+(NSData *)sha1:(SecCertificateRef) cert {
    // fingerprint is over canonical DER rep.
    CFDataRef data = SecCertificateCopyData(cert);
    NSData * out = [[NSData dataWithBytes:CFDataGetBytePtr(data) length:CFDataGetLength(data)] sha1Digest];
    CFRelease(data);
    return out;
}

它在目标C中有点短.它需要NSData / NSString的以下扩展,但要使格式接近netscape,OSX或Windows.

- (NSData *)md5Digest
{
    unsigned char result[CC_MD5_DIGEST_LENGTH];

    CC_MD5([self bytes],(CC_LONG)[self length],result);
    return [NSData dataWithBytes:result length:CC_MD5_DIGEST_LENGTH];
}

- (NSData *)sha1Digest
{
    unsigned char result[CC_SHA1_DIGEST_LENGTH];

    CC_SHA1([self bytes],result);
    return [NSData dataWithBytes:result length:CC_SHA1_DIGEST_LENGTH];
}

- (NSString *)hexstringvalue
{
    NSMutableString *StringBuffer = [NSMutableString StringWithCapacity:([self length] * 2)];

    const unsigned char *dataBuffer = [self bytes];
    int i;

    for (i = 0; i < [self length]; ++i)
    {
        [StringBuffer appendFormat:@"%02lx",(unsigned long)dataBuffer[i]];
    }

    return [StringBuffer copy];
}


- (NSString *)hexColonSeperatedstringvalue
{
    return [self hexColonSeperatedstringvalueWithCapitals:YES];
}

- (NSString *)hexColonSeperatedstringvalueWithCapitals:(BOOL)capitalize {
    NSMutableString *StringBuffer = [NSMutableString StringWithCapacity:([self length] * 3)];

    const unsigned char *dataBuffer = [self bytes];
    NSString * format = capitalize ? @"%02X" : @"%02x";
    int i;

    for (i = 0; i < [self length]; ++i)
    {
        if (i) 
            [StringBuffer appendString:@":"];
        [StringBuffer appendFormat:format,(unsigned long)dataBuffer[i]];
    }

    return [StringBuffer copy];
}