I am implementing an ECDSA NIST test vectors verification application. The test vectors are taken from http://csrc.nist.gov/groups/STM/cavp/#09.
One of the test vectors is given below:
P-192 SHA1
Msg = 608079423f12421de616b7493ebe551cf4d65b92
d = e14f37b3d1374ff8b03f41b9b3fdd2f0ebccf275d660d7f3
Qx = 07008ea40b08dbe76432096e80a2494c94982d2d5bcf98e6
Qy = 76fab681d00b414ea636ba215de26d98c41bd7f2e4d65477
k = cb0abc7043a10783684556fb12c4154d57bc31a289685f25
R = 6994d962bdd0d793ffddf855ec5bf2f91a9698b46258a63e
S = 02ba6465a234903744ab02bc8521405b73cf5fc00e1a9f41
I am trying to calculate $k_{inv}$ from given $k$ value and I am using curve “NID_X9_62_prime192v1”.
Can anyone tell me how to calculate $k_{inv}$?