KADM5_PWCHECK(3)         BSD Library Functions Manual         KADM5_PWCHECK(3)

NAME
     krb5_pwcheck, kadm5_setup_passwd_quality_check,
     kadm5_add_passwd_quality_verifier, kadm5_check_password_quality -- Heim-
     dal warning and error functions

LIBRARY
     Kerberos 5 Library (libkadm5srv, -lkadm5srv)

SYNOPSIS
     #include <kadm5-protos.h>
     #include <kadm5-pwcheck.h>

     void
     kadm5_setup_passwd_quality_check(krb5_context context,
         const char *check_library, const char *check_function);

     krb5_error_code
     kadm5_add_passwd_quality_verifier(krb5_context context,
         const char *check_library);

     const char *
     kadm5_check_password_quality(krb5_context context,
         krb5_principal principal, krb5_data *pwd_data);

     int
     (*kadm5_passwd_quality_check_func)(krb5_context context,
         krb5_principal principal, krb5_data *password, const char *tuning,
         char *message, size_t length);

DESCRIPTION
     These functions perform the quality check for the heimdal database
     library.

     There are two versions of the shared object API; the old version (0) is
     deprecated, but still supported.  The new version (1) supports multiple
     password quality checking policies in the same shared object.  See below
     for details.

     The password quality checker will run all policies that are configured by
     the user.  If any policy rejects the password, the password will be
     rejected.

     Policy names are of the form `module-name:policy-name' or, if the the
     policy name is unique enough, just `policy-name'.

IMPLEMENTING A PASSWORD QUALITY CHECKING SHARED OBJECT
     (This refers to the version 1 API only.)

     Module shared objects may conveniently be compiled and linked with
     libtool(1).  An object needs to export a symbol called
     `kadm5_password_verifier' of the type struct kadm5_pw_policy_verifier.

     Its name and vendor fields should contain the obvious information.  name
     must match the `module-name' portion of the policy name (the part before
     the colon), if the policy name contains a colon, or the policy will not
     be run.  version should be KADM5_PASSWD_VERSION_V1.

     funcs contains an array of struct kadm5_pw_policy_check_func structures
     that is terminated with an entry whose name component is NULL.  The name
     field of the array must match the `policy-name' portion of a policy name
     (the part after the colon, or the complete policy name if there is no
     colon) specified by the user or the policy will not be run.  The func
     fields of the array elements are functions that are exported by the mod-
     ule to be called to check the password.  They get the following argu-
     ments:  the Kerberos context, principal, password, a tuning parameter,
     and a pointer to a message buffer and its length.  The tuning parameter
     for the quality check function is currently always NULL.  If the password
     is acceptable, the function returns zero.  Otherwise it returns non-zero
     and fills in the message buffer with an appropriate explanation.

RUNNING THE CHECKS
     kadm5_setup_passwd_quality_check sets up type 0 checks.  It sets up all
     type 0 checks defined in krb5.conf(5) if called with the last two argu-
     ments null.

     kadm5_add_passwd_quality_verifier sets up type 1 checks.  It sets up all
     type 1 tests defined in krb5.conf(5) if called with a null second argu-
     ment.  kadm5_check_password_quality runs the checks in the order in which
     they are defined in krb5.conf(5) and the order in which they occur in a
     module's funcs array until one returns non-zero.

SEE ALSO
     libtool(1), krb5(3), krb5.conf(5)

HEIMDAL                        February 29, 2004                       HEIMDAL
