.\"	$NetBSD: krb5_get_init_creds.3,v 1.2 2017/01/28 21:31:49 christos Exp $
.\"
.\" Copyright (c) 2003 - 2007 Kungliga Tekniska Högskolan
.\" (Royal Institute of Technology, Stockholm, Sweden).
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\"
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\"
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" 3. Neither the name of the Institute nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" Id
.\"
.Dd Sep  16, 2006
.Dt KRB5_GET_INIT_CREDS 3
.Os
.Sh NAME
.Nm krb5_get_init_creds ,
.Nm krb5_get_init_creds_keytab ,
.Nm krb5_get_init_creds_opt ,
.Nm krb5_get_init_creds_opt_alloc ,
.Nm krb5_get_init_creds_opt_free ,
.Nm krb5_get_init_creds_opt_init ,
.Nm krb5_get_init_creds_opt_set_address_list ,
.Nm krb5_get_init_creds_opt_set_addressless ,
.Nm krb5_get_init_creds_opt_set_anonymous ,
.Nm krb5_get_init_creds_opt_set_default_flags ,
.Nm krb5_get_init_creds_opt_set_etype_list ,
.Nm krb5_get_init_creds_opt_set_forwardable ,
.Nm krb5_get_init_creds_opt_set_pa_password ,
.Nm krb5_get_init_creds_opt_set_paq_request ,
.Nm krb5_get_init_creds_opt_set_preauth_list ,
.Nm krb5_get_init_creds_opt_set_proxiable ,
.Nm krb5_get_init_creds_opt_set_renew_life ,
.Nm krb5_get_init_creds_opt_set_salt ,
.Nm krb5_get_init_creds_opt_set_tkt_life ,
.Nm krb5_get_init_creds_opt_set_canonicalize ,
.Nm krb5_get_init_creds_opt_set_win2k ,
.Nm krb5_get_init_creds_password ,
.Nm krb5_prompt ,
.Nm krb5_prompter_posix
.Nd Kerberos 5 initial authentication functions
.Sh LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)
.Sh SYNOPSIS
.In krb5/krb5.h
.Pp
.Ft krb5_get_init_creds_opt;
.Pp
.Ft krb5_error_code
.Fo krb5_get_init_creds_opt_alloc
.Fa "krb5_context context"
.Fa "krb5_get_init_creds_opt **opt"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_free
.Fa "krb5_context context"
.Fa "krb5_get_init_creds_opt *opt"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_init
.Fa "krb5_get_init_creds_opt *opt"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_address_list
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_addresses *addresses"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_addressless
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_boolean addressless"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_anonymous
.Fa "krb5_get_init_creds_opt *opt"
.Fa "int anonymous"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_change_password_prompt
.Fa "krb5_get_init_creds_opt *opt"
.Fa "int change_password_prompt"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_default_flags
.Fa "krb5_context context"
.Fa "const char *appname"
.Fa "krb5_const_realm realm"
.Fa "krb5_get_init_creds_opt *opt"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_etype_list
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_enctype *etype_list"
.Fa "int etype_list_length"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_forwardable
.Fa "krb5_get_init_creds_opt *opt"
.Fa "int forwardable"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds_opt_set_pa_password
.Fa "krb5_context context"
.Fa "krb5_get_init_creds_opt *opt"
.Fa "const char *password"
.Fa "krb5_s2k_proc key_proc"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds_opt_set_paq_request
.Fa "krb5_context context"
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_boolean req_pac"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds_opt_set_pkinit
.Fa "krb5_context context"
.Fa "krb5_get_init_creds_opt *opt"
.Fa "const char *cert_file"
.Fa "const char *key_file"
.Fa "const char *x509_anchors"
.Fa "int flags"
.Fa "char *password"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_preauth_list
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_preauthtype *preauth_list"
.Fa "int preauth_list_length"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_proxiable
.Fa "krb5_get_init_creds_opt *opt"
.Fa "int proxiable"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_renew_life
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_deltat renew_life"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_salt
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_data *salt"
.Fc
.Ft void
.Fo krb5_get_init_creds_opt_set_tkt_life
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_deltat tkt_life"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds_opt_set_canonicalize
.Fa "krb5_context context"
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_boolean req"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds_opt_set_win2k
.Fa "krb5_context context"
.Fa "krb5_get_init_creds_opt *opt"
.Fa "krb5_boolean req"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds
.Fa "krb5_context context"
.Fa "krb5_creds *creds"
.Fa "krb5_principal client"
.Fa "krb5_prompter_fct prompter"
.Fa "void *prompter_data"
.Fa "krb5_deltat start_time"
.Fa "const char *in_tkt_service"
.Fa "krb5_get_init_creds_opt *options"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds_password
.Fa "krb5_context context"
.Fa "krb5_creds *creds"
.Fa "krb5_principal client"
.Fa "const char *password"
.Fa "krb5_prompter_fct prompter"
.Fa "void *prompter_data"
.Fa "krb5_deltat start_time"
.Fa "const char *in_tkt_service"
.Fa "krb5_get_init_creds_opt *in_options"
.Fc
.Ft krb5_error_code
.Fo krb5_get_init_creds_keytab
.Fa "krb5_context context"
.Fa "krb5_creds *creds"
.Fa "krb5_principal client"
.Fa "krb5_keytab keytab"
.Fa "krb5_deltat start_time"
.Fa "const char *in_tkt_service"
.Fa "krb5_get_init_creds_opt *options"
.Fc
.Ft int
.Fo krb5_prompter_posix
.Fa "krb5_context context"
.Fa "void *data"
.Fa "const char *name"
.Fa "const char *banner"
.Fa "int num_prompts"
.Fa "krb5_prompt prompts[]"
.Fc
.Sh DESCRIPTION
Getting initial credential ticket for a principal.
That may include changing an expired password, and doing preauthentication.
This interface that replaces the deprecated
.Fa krb5_in_tkt
and
.Fa krb5_in_cred
functions.
.Pp
If you only want to verify a username and password, consider using
.Xr krb5_verify_user 3
instead, since it also verifies that initial credentials with using a
keytab to make sure the response was from the KDC.
.Pp
First a
.Li krb5_get_init_creds_opt
structure is initialized
with
.Fn krb5_get_init_creds_opt_alloc
or
.Fn krb5_get_init_creds_opt_init .
.Fn krb5_get_init_creds_opt_alloc
allocates a extendible structures that needs to be freed with
.Fn krb5_get_init_creds_opt_free .
The structure may be modified by any of the
.Fn krb5_get_init_creds_opt_set
functions to change request parameters and authentication information.
.Pp
If the caller want to use the default options,
.Dv NULL
can be passed instead.
.Pp
The the actual request to the KDC is done by any of the
.Fn krb5_get_init_creds ,
.Fn krb5_get_init_creds_password ,
or
.Fn krb5_get_init_creds_keytab
functions.
.Fn krb5_get_init_creds
is the least specialized function and can, with the right in data,
behave like the latter two.
The latter two are there for compatibility with older releases and
they are slightly easier to use.
.Pp
.Li krb5_prompt
is a structure containing the following elements:
.Bd -literal
typedef struct {
    const char *prompt;
    int hidden;
    krb5_data *reply;
    krb5_prompt_type type
} krb5_prompt;
.Ed
.Pp
.Fa prompt
is the prompt that should shown to the user
If
.Fa hidden
is set, the prompter function shouldn't echo the output to the display
device.
.Fa reply
must be preallocated; it will not be allocated by the prompter
function.
Possible values for the
.Fa type
element are:
.Pp
.Bl -tag -width Ds -compact -offset indent
.It KRB5_PROMPT_TYPE_PASSWORD
.It KRB5_PROMPT_TYPE_NEW_PASSWORD
.It KRB5_PROMPT_TYPE_NEW_PASSWORD_AGAIN
.It KRB5_PROMPT_TYPE_PREAUTH
.It KRB5_PROMPT_TYPE_INFO
.El
.Pp
.Fn krb5_prompter_posix
is the default prompter function in a POSIX environment.
It matches the
.Fa krb5_prompter_fct
and can be used in the
.Fa krb5_get_init_creds
functions.
.Fn krb5_prompter_posix
doesn't require
.Fa prompter_data.
.Pp
If the
.Fa start_time
is zero, then the requested ticket will be valid
beginning immediately.
Otherwise, the
.Fa start_time
indicates how far in the future the ticket should be postdated.
.Pp
If the
.Fa in_tkt_service
name is
.Dv non-NULL ,
that principal name will be
used as the server name for the initial ticket request.
The realm of the name specified will be ignored and will be set to the
realm of the client name.
If no in_tkt_service name is specified,
krbtgt/CLIENT-REALM@CLIENT-REALM will be used.
.Pp
For the rest of arguments, a configuration or library default will be
used if no value is specified in the options structure.
.Pp
.Fn krb5_get_init_creds_opt_set_address_list
sets the list of
.Fa addresses
that is should be stored in the ticket.
.Pp
.Fn krb5_get_init_creds_opt_set_addressless
controls if the ticket is requested with addresses or not,
.Fn krb5_get_init_creds_opt_set_address_list
overrides this option.
.Pp
.Fn krb5_get_init_creds_opt_set_anonymous
make the request anonymous if the
.Fa anonymous
parameter is non-zero.
.Pp
.Fn krb5_get_init_creds_opt_set_default_flags
sets the default flags using the configuration file.
.Pp
.Fn krb5_get_init_creds_opt_set_etype_list
set a list of enctypes that the client is willing to support in the
request.
.Pp
.Fn krb5_get_init_creds_opt_set_forwardable
request a forwardable ticket.
.Pp
.Fn krb5_get_init_creds_opt_set_pa_password
set the
.Fa password
and
.Fa key_proc
that is going to be used to get a new ticket.
.Fa password
or
.Fa key_proc
can be
.Dv NULL
if the caller wants to use the default values.
If the
.Fa password
is unset and needed, the user will be prompted for it.
.Pp
.Fn krb5_get_init_creds_opt_set_paq_request
sets the password that is going to be used to get a new ticket.
.Pp
.Fn krb5_get_init_creds_opt_set_preauth_list
sets the list of client-supported preauth types.
.Pp
.Fn krb5_get_init_creds_opt_set_proxiable
makes the request proxiable.
.Pp
.Fn krb5_get_init_creds_opt_set_renew_life
sets the requested renewable lifetime.
.Pp
.Fn krb5_get_init_creds_opt_set_salt
sets the salt that is going to be used in the request.
.Pp
.Fn krb5_get_init_creds_opt_set_tkt_life
sets requested ticket lifetime.
.Pp
.Fn krb5_get_init_creds_opt_set_canonicalize
requests that the KDC canonicalize the client principal if possible.
.Pp
.Fn krb5_get_init_creds_opt_set_win2k
turns on compatibility with Windows 2000.
.Sh SEE ALSO
.Xr krb5 3 ,
.Xr krb5_creds 3 ,
.Xr krb5_verify_user 3 ,
.Xr krb5.conf 5 ,
.Xr kerberos 8