xref: /freebsd/crypto/heimdal/lib/kadm5/kadm5_pwcheck.3 (revision 09a53ad8f1318c5daae6cfb19d97f4f6459f0013)
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32.\" $Id$
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34.Dd February 29, 2004
35.Dt KADM5_PWCHECK 3
36.Os HEIMDAL
37.Sh NAME
38.Nm krb5_pwcheck ,
39.Nm kadm5_setup_passwd_quality_check ,
40.Nm kadm5_add_passwd_quality_verifier ,
41.Nm kadm5_check_password_quality
42.Nd Heimdal warning and error functions
43.Sh LIBRARY
44Kerberos 5 Library (libkadm5srv, -lkadm5srv)
45.Sh SYNOPSIS
46.In kadm5-protos.h
47.In kadm5-pwcheck.h
48.Ft void
49.Fo kadm5_setup_passwd_quality_check
50.Fa "krb5_context context"
51.Fa "const char *check_library"
52.Fa "const char *check_function"
53.Fc
54.Ft "krb5_error_code"
55.Fo kadm5_add_passwd_quality_verifier
56.Fa "krb5_context context"
57.Fa "const char *check_library"
58.Fc
59.Ft "const char *"
60.Fo kadm5_check_password_quality
61.Fa "krb5_context context"
62.Fa "krb5_principal principal"
63.Fa "krb5_data *pwd_data"
64.Fc
65.Ft int
66.Fo "(*kadm5_passwd_quality_check_func)"
67.Fa "krb5_context context"
68.Fa "krb5_principal principal"
69.Fa "krb5_data *password"
70.Fa "const char *tuning"
71.Fa "char *message"
72.Fa "size_t length"
73.Fc
74.Sh DESCRIPTION
75These functions perform the quality check for the heimdal database
76library.
77.Pp
78There are two versions of the shared object API; the old version (0)
79is deprecated, but still supported.  The new version (1) supports
80multiple password quality checking policies in the same shared object.
81See below for details.
82.Pp
83The password quality checker will run all policies that are
84configured by the user.  If any policy rejects the password, the password
85will be rejected.
86.Pp
87Policy names are of the form
88.Ql module-name:policy-name
89or, if the the policy name is unique enough, just
90.Ql policy-name .
91.Sh IMPLEMENTING A PASSWORD QUALITY CHECKING SHARED OBJECT
92(This refers to the version 1 API only.)
93.Pp
94Module shared objects may conveniently be compiled and linked with
95.Xr libtool 1 .
96An object needs to export a symbol called
97.Ql kadm5_password_verifier
98of the type
99.Ft "struct kadm5_pw_policy_verifier" .
100.Pp
101Its
102.Ft name
103and
104.Ft vendor
105fields should contain the obvious information.
106.Ft name
107must match the
108.Ql module-name
109portion of the policy name (the part before the colon), if the policy name
110contains a colon, or the policy will not be run.
111.Ft version
112should be
113.Dv KADM5_PASSWD_VERSION_V1 .
114.Pp
115.Ft funcs
116contains an array of
117.Ft "struct kadm5_pw_policy_check_func"
118structures that is terminated with an entry whose
119.Ft name
120component is
121.Dv NULL .
122The
123.Ft name
124field of the array must match the
125.Ql policy-name
126portion of a policy name (the part after the colon, or the complete policy
127name if there is no colon) specified by the user or the policy will not be
128run.  The
129.Ft func
130fields of the array elements are functions that are exported by the
131module to be called to check the password.  They get the following
132arguments:  the Kerberos context, principal, password, a tuning parameter, and
133a pointer to a message buffer and its length.  The tuning parameter
134for the quality check function is currently always
135.Dv NULL .
136If the password is acceptable, the function returns zero.  Otherwise
137it returns non-zero and fills in the message buffer with an
138appropriate explanation.
139.Sh RUNNING THE CHECKS
140.Nm kadm5_setup_passwd_quality_check
141sets up type 0 checks.  It sets up all type 0 checks defined in
142.Xr krb5.conf 5
143if called with the last two arguments null.
144.Pp
145.Nm kadm5_add_passwd_quality_verifier
146sets up type 1 checks.  It sets up all type 1 tests defined in
147.Xr krb5.conf 5
148if called with a null second argument.
149.Nm kadm5_check_password_quality
150runs the checks in the order in which they are defined in
151.Xr krb5.conf 5
152and the order in which they occur in a
153module's
154.Ft funcs
155array until one returns non-zero.
156.Sh SEE ALSO
157.Xr libtool 1 ,
158.Xr krb5 3 ,
159.Xr krb5.conf 5
160