OPENPAM_SUBST(3) BSD Library Functions Manual OPENPAM_SUBST(3)
openpam_subst -- substitute PAM item values in a string
Pluggable Authentication Module Library (libpam, -lpam)
openpam_subst(const pam_handle_t *pamh, char *buf, size_t *bufsize, const char *template);
The openpam_subst function expands a string, substituting PAM item values for all occur-
rences of specific substitution codes. The template argument points to the initial string.
The result is stored in the buffer pointed to by the buf argument; the 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 bufsize argument.
If buf is NULL, or if the buffer is too small to hold the expanded string, bufsize is
updated to reflect the amount of space required to hold the entire string, and openpam_subst
If openpam_subst fails for any other reason, the bufsize argument is untouched, but part of
the buffer may still have been overwritten.
Substitution codes are introduced by a percent character and correspond to PAM items:
%H Replaced by the current value of the PAM_RHOST item.
%h Replaced by the current value of the PAM_HOST item.
%s Replaced by the current value of the PAM_SERVICE item.
%t Replaced by the current value of the PAM_TTY item.
%U Replaced by the current value of the PAM_RUSER item.
%u Replaced by the current value of the PAM_USER item.
The openpam_subst function returns one of the following values:
[PAM_SYSTEM_ERR] System error.
[PAM_TRY_AGAIN] Try again.
pam(3), pam_get_authtok(3), pam_get_item(3), pam_get_user(3), pam_strerror(3)
The openpam_subst function is an OpenPAM extension.
The openpam_subst function and this manual page were developed for the FreeBSD Project by
Dag-Erling Smorgrav <des@FreeBSD.org>.
BSD December 18, 2011 BSD