cd /usr/src/sbin/pppd
Прописал в Макеfile.
далее make и на файлика auth.c вот с такой ошибочкой вылетает:

Warning: Object directory not changed from original /usr/src/usr.sbin/pppd
cc -O -pipe  -DHAVE_PATHS_H -DUSE_PAM -DCBCP_SUPPORT -DPPP_FILTER -DCHAPMS  -c a
uth.c
auth.c: In function `plogin':
auth.c:863: warning: passing arg 1 of `pam_strerror' makes pointer from integer
without a cast
auth.c:863: error: too few arguments to function `pam_strerror'
auth.c:884: warning: passing arg 1 of `pam_strerror' makes pointer from integer
without a cast
auth.c:884: error: too few arguments to function `pam_strerror'
*** Error code 1

Stop in /usr/src/usr.sbin/pppd.