The PKCS#11 shared library is the core software component that bridges the Kron PAM JVM and the Utimaco u.trust GP HSM. It implements the PKCS#11 v2.20 API but translates those calls into the proprietary CryptoServer protocol understood by the Utimaco hardware. Without this library on the Kron PAM server, SunPKCS11 cannot communicate with the device.
Copy the library to the standard shared library location and set the correct permissions. The file must be executable by the system but does not need to be writable by application users:
[pamuser@KronPAM_Instance]# cp libcs_pkcs11_R3.so /usr/lib64/libcs_pkcs11_R3.so
[pamuser@KronPAM_Instance]# chmod 755 /usr/lib64/libcs_pkcs11_R3.so