oath_totp_validate4 - API function
Contents
Arguments
const char * secret
the shared secret string
size_t secret_length
length of secret
time_t now Unix time value to validate TOTP for
unsigned time_step_size
time step system parameter (typically 30)
time_t start_offset
Unix time of when to start counting time steps (typically 0)
size_t window
how many OTPs after/before start OTP to test
int * otp_pos
output search position in search window (may be NULL).
uint64_t * otp_counter
counter value used to calculate OTP value (may be NULL).
int flags flags indicating mode, one of oath_totp_flags
const char * otp
the OTP to validate.
Copyright
Copyright © 2009-2020 Simon Josefsson.
Copying and distribution of this file, with or without modification, are permitted in any medium without
royalty provided the copyright notice and this notice are preserved.
liboath 2.6.12 oath_totp_validate4(3)
Description
Validate an OTP according to OATH TOTP algorithm per RFC 6238.
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.
The flags parameter may be used to change the MAC function, for example OATH_TOTP_HMAC_SHA256 or
OATH_TOTP_HMAC_SHA512.
Name
oath_totp_validate4 - API function
Reporting Bugs
Report bugs to <oath-toolkit-help@nongnu.org>. liboath home page: https://www.nongnu.org/oath-toolkit/
General help using GNU software: http://www.gnu.org/gethelp/
Returns
Returns absolute value of position in OTP window (zero is first position), or OATH_INVALID_OTP if no OTP
was found in OTP window, or an error code.
Since
2.6.0
Synopsis
#include<oath.h>intoath_totp_validate4(constchar*secret,size_tsecret_length,time_tnow,unsignedtime_step_size,time_tstart_offset,size_twindow,int*otp_pos,uint64_t*otp_counter,intflags,constchar*otp);
