ios SHA256加密

- (NSData*) sha256:(NSString *)stringpass
{
NSData *data = [self
hexStrToNSData:stringpass];

uint8_t digest[CC_SHA256_DIGEST_LENGTH];

CC_SHA256(data.bytes,data.length, digest);

NSData *strForHas=[[NSData
alloc]initWithBytes:digest
length:CC_SHA256_DIGEST_LENGTH];

return strForHas;
}

//十六進位字串轉bytes
-(NSData *) hexStrToNSData:(NSString *)hexStr
{
NSMutableData* data = [NSMutableData
data];
int idx;
for (idx =
0; idx+2 <= hexStr.length; idx+=2) {
NSRange range =
NSMakeRange(idx, 2);
NSString* ch = [hexStr
substringWithRange:range];
NSScanner* scanner = [NSScanner
scannerWithString:ch];
unsigned
int intValue;
[scanner scanHexInt:&intValue];
[data appendBytes:&intValue
length:1];
}
return data;
}