$Id: openpam_subst.c 648 2013-03-05 17:54:27Z des $
.Dd September 12, 2014 .Dt OPENPAM_SUBST 3 .Os .Sh NAME .Nm openpam_subst .Nd substitute PAM item values in a string .Sh LIBRARY .Lb libpam .Sh SYNOPSIS n sys/types.h n security/pam_appl.h n security/openpam.h .Ft "int" .Fn openpam_subst "const pam_handle_t *pamh" "char *buf" "size_t *bufsize" "const char *template" .Sh DESCRIPTION The .Fn openpam_subst function expands a string, substituting PAM item values for all occurrences of specific substitution codes. The .Fa template argument points to the initial string. The result is stored in the buffer pointed to by the .Fa buf argument; the .Fa bufsize argument specifies the size of that buffer. The actual size of the resulting string, including the terminating NUL character, is stored in the location pointed to by the .Fa bufsize argument.
p If .Fa buf is NULL, or if the buffer is too small to hold the expanded string, .Fa bufsize is updated to reflect the amount of space required to hold the entire string, and .Fn openpam_subst returns .Dv PAM_TRY_AGAIN .
p If .Fn openpam_subst fails for any other reason, the .Fa bufsize argument is untouched, but part of the buffer may still have been overwritten.
p Substitution codes are introduced by a percent character and correspond to PAM items: l -tag -width 18n t %H Replaced by the current value of the .Dv PAM_RHOST item. t %h Replaced by the current value of the .Dv PAM_HOST item. t %s Replaced by the current value of the .Dv PAM_SERVICE item. t %t Replaced by the current value of the .Dv PAM_TTY item. t %U Replaced by the current value of the .Dv PAM_RUSER item. t %u Replaced by the current value of the .Dv PAM_USER item. .El .Sh RETURN VALUES The .Fn openpam_subst function returns one of the following values: l -tag -width 18n t Bq Er PAM_SYSTEM_ERR System error. t Bq Er PAM_TRY_AGAIN Try again. .El .Sh SEE ALSO .Xr pam 3 , .Xr pam_get_authtok 3 , .Xr pam_get_item 3 , .Xr pam_get_user 3 , .Xr pam_strerror 3 .Sh STANDARDS The .Fn openpam_subst function is an OpenPAM extension. .Sh AUTHORS The .Fn openpam_subst function and this manual page were developed by .An Dag-Erling Sm\(/orgrav Aq des@des.no .