Fix buffer overflow in write_chalresp_state()
Fix buffer overflow in write_chalresp_state()

Buffer was defined as CR_SALT_SIZE = 32 but number of random bytes
was CR_CHALLENGE_SIZE = 63.

Yubico/yubico-pam,eworm-de/yubico-pam,eworm-de/yubico-pam,Yubico/yubico-pam,Yubico/yubico-pam,eworm-de/yubico-pam