sha1算法

- (NSString *) sha1:(NSString *)input

{

const char *cstr = [input cStringUsingEncoding:NSUTF8StringEncoding];

NSData *data = [NSData dataWithBytes:cstr length:input.length];

uint8_t digest[CC_SHA1_DIGEST_LENGTH];

CC_SHA1(data.bytes, data.length, digest);

NSMutableString *output = [NSMutableString stringWithCapacity:CC_SHA1_DIGEST_LENGTH * 2];

for(int i=0; i