oath_hotp_validate man page

oath_hotp_validate — API function


#include <oath.h>

int oath_hotp_validate(const char * secret, size_t secret_length, uint64_t start_moving_factor, size_t window, const char * otp);


const char * secret

the shared secret string

size_t secret_length

length of secret

uint64_t start_moving_factor

start counter in OTP stream

size_t window

how many OTPs after start counter to test

const char * otp

the OTP to validate.


Validate an OTP according to OATH HOTP algorithm per RFC 4226.

Currently only OTP lengths of 6, 7 or 8 digits are supported.  This restrictions may be lifted in future versions, although some limitations are inherent in the protocol.


Returns position in OTP window (zero is first position), or OATH_INVALID_OTP if no OTP was found in OTP window, or an error code.

Reporting Bugs

Report bugs to <oath-toolkit-help@nongnu.org>. liboath home page: http://www.gnu.org/software/liboath/ General help using GNU software: http://www.gnu.org/gethelp/


2.6.1 liboath