PAM_SET_DATA(3)                 Linux-PAM Manual                 PAM_SET_DATA(3)

       pam_set_data - set module internal data

       #include <security/pam_modules.h>

       int pam_set_data(pam_handle_t *pamh, const char *module_data_name,
                        void *data,
                        void (*cleanup)(pam_handle_t *pamh, void *data, int error_status));

       The pam_set_data function associates a pointer to an object with the
       (hopefully) unique string module_data_name in the PAM context specified
       by the pamh argument.

       PAM modules may be dynamically loadable objects. In general such files
       should not contain static variables. This function and its counterpart
       pam_get_data(3), provide a mechanism for a module to associate some data
       with the handle pamh. Typically a module will call the pam_set_data
       function to register some data under a (hopefully) unique
       module_data_name. The data is available for use by other modules too but
       not by an application. Since this functions stores only a pointer to the
       data, the module should not modify or free the content of it.

       The function cleanup() is associated with the data and, if non-NULL, it
       is called when this data is over-written or following a call to

       The error_status argument is used to indicate to the module the sort of
       action it is to take in cleaning this data item. As an example, Kerberos
       creates a ticket file during the authentication phase, this file might be
       associated with a data item. When pam_end(3) is called by the module, the
       error_status carries the return value of the pam_authenticate(3) or other
       libpam function as appropriate. Based on this value the Kerberos module
       may choose to delete the ticket file (authentication failure) or leave it
       in place.

       The error_status may have been logically OR'd with either of the
       following two values:

           When a data item is being replaced (through a second call to
           pam_set_data) this mask is used. Otherwise, the call is assumed to be
           from pam_end(3).

           Which indicates that the process would prefer to perform the
           cleanup() quietly. That is, discourages logging/messages to the user.

           Memory buffer error.

           Data was successful stored.

           A NULL pointer was submitted as PAM handle or the function was called
           by an application.

       pam_end(3), pam_get_data(3), pam_strerror(3)

Linux-PAM Manual                   11/10/2020                    PAM_SET_DATA(3)