pam_sm_authenticate 3 Linux-PAM Manual pam_sm_authenticate PAM service function for user authentication #define PAM_SM_AUTH #include <security/pam_modules.h> int pam_sm_authenticate pam_handle_t *pamh int flags int argc const char **argv The pam_sm_authenticate function is the service module's implementation of the pam_authenticate3 interface. This function performs the task of authenticating the user. Valid flags, which may be logically OR'd with PAM_SILENT, are: PAM_SILENT Do not emit any messages. PAM_DISALLOW_NULL_AUTHTOK Return PAM_AUTH_ERR if the database of authentication tokens for this authentication mechanism has a NULL entry for the user. Without this flag, such a NULL token will lead to a success without the user being prompted. PAM_AUTH_ERR Authentication failure. PAM_CRED_INSUFFICIENT For some reason the application does not have sufficient credentials to authenticate the user. PAM_AUTHINFO_UNAVAIL The modules were not able to access the authentication information. This might be due to a network or hardware failure etc. PAM_SUCCESS The authentication token was successfully updated. PAM_USER_UNKNOWN The supplied username is not known to the authentication service. PAM_MAXTRIES One or more of the authentication modules has reached its limit of tries authenticating the user. Do not try again. pam3 , pam_authenticate3 , pam_sm_setcred3 , pam_strerror3 , PAM8