2005-12-29 14:40:22 +00:00
|
|
|
.\" -*- nroff -*-
|
|
|
|
.\"
|
|
|
|
.\" Copyright (c) 2005 Doug Rabson
|
|
|
|
.\" 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.
|
|
|
|
.\"
|
|
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
|
|
.\"
|
|
|
|
.\" $FreeBSD$
|
|
|
|
.\"
|
|
|
|
.\" The following commands are required for all man pages.
|
2010-01-26 15:03:33 +00:00
|
|
|
.Dd January 26, 2010
|
2005-12-29 14:40:22 +00:00
|
|
|
.Dt GSS_ACCEPT_SEC_CONTEXT 3 PRM
|
2010-04-14 19:08:06 +00:00
|
|
|
.Os
|
2005-12-29 14:40:22 +00:00
|
|
|
.Sh NAME
|
|
|
|
.Nm gss_accept_sec_context
|
|
|
|
.Nd Accept a security context initiated by a peer application
|
|
|
|
.\" This next command is for sections 2 and 3 only.
|
|
|
|
.\" .Sh LIBRARY
|
|
|
|
.Sh SYNOPSIS
|
|
|
|
.In "gssapi/gssapi.h"
|
|
|
|
.Ft OM_uint32
|
|
|
|
.Fo gss_accept_sec_context
|
2012-03-26 15:18:14 +00:00
|
|
|
.Fa "OM_uint32 *minor_status"
|
2005-12-29 14:40:22 +00:00
|
|
|
.Fa "gss_ctx_id_t *context_handle"
|
|
|
|
.Fa "const gss_cred_id_t acceptor_cred_handle"
|
|
|
|
.Fa "const gss_buffer_t input_token_buffer"
|
|
|
|
.Fa "const gss_channel_bindings_t input_chan_bindings"
|
|
|
|
.Fa "const gss_name_t *src_name"
|
|
|
|
.Fa "gss_OID *mech_type"
|
|
|
|
.Fa "gss_buffer_t output_token"
|
|
|
|
.Fa "OM_uint32 *ret_flags"
|
|
|
|
.Fa "OM_uint32 *time_rec"
|
|
|
|
.Fa "gss_cred_id_t *delegated_cred_handle"
|
|
|
|
.Fc
|
|
|
|
.Sh DESCRIPTION
|
|
|
|
Allows a remotely initiated security context between the application
|
|
|
|
and a remote peer to be established. The routine may return a
|
|
|
|
.Fa output_token
|
|
|
|
which should be transferred to the peer application,
|
|
|
|
where the peer application will present it to
|
|
|
|
.Xr gss_init_sec_context 3 .
|
|
|
|
If no token need be sent,
|
|
|
|
.Fn gss_accept_sec_context
|
|
|
|
will indicate this
|
|
|
|
by setting the length field of the
|
|
|
|
.Fa output_token
|
|
|
|
argument to zero.
|
|
|
|
To complete the context establishment, one or more reply tokens may be
|
|
|
|
required from the peer application; if so,
|
|
|
|
.Fn gss_accept_sec_context
|
|
|
|
will return a status flag of
|
|
|
|
.Dv GSS_S_CONTINUE_NEEDED , in which case it
|
|
|
|
should be called again when the reply token is received from the peer
|
|
|
|
application, passing the token to
|
|
|
|
.Fn gss_accept_sec_context
|
|
|
|
via the
|
|
|
|
.Fa input_token
|
|
|
|
parameters.
|
|
|
|
.Pp
|
|
|
|
Portable applications should be constructed to use the token length
|
|
|
|
and return status to determine whether a token needs to be sent or
|
|
|
|
waited for. Thus a typical portable caller should always invoke
|
|
|
|
.Fn gss_accept_sec_context
|
|
|
|
within a loop:
|
|
|
|
.Bd -literal
|
|
|
|
gss_ctx_id_t context_hdl = GSS_C_NO_CONTEXT;
|
|
|
|
|
|
|
|
do {
|
|
|
|
receive_token_from_peer(input_token);
|
|
|
|
maj_stat = gss_accept_sec_context(&min_stat,
|
|
|
|
&context_hdl,
|
|
|
|
cred_hdl,
|
|
|
|
input_token,
|
|
|
|
input_bindings,
|
|
|
|
&client_name,
|
|
|
|
&mech_type,
|
|
|
|
output_token,
|
|
|
|
&ret_flags,
|
|
|
|
&time_rec,
|
|
|
|
&deleg_cred);
|
|
|
|
if (GSS_ERROR(maj_stat)) {
|
|
|
|
report_error(maj_stat, min_stat);
|
|
|
|
};
|
|
|
|
if (output_token->length != 0) {
|
|
|
|
send_token_to_peer(output_token);
|
|
|
|
|
|
|
|
gss_release_buffer(&min_stat, output_token);
|
|
|
|
};
|
|
|
|
if (GSS_ERROR(maj_stat)) {
|
|
|
|
if (context_hdl != GSS_C_NO_CONTEXT)
|
|
|
|
gss_delete_sec_context(&min_stat,
|
|
|
|
&context_hdl,
|
|
|
|
GSS_C_NO_BUFFER);
|
|
|
|
break;
|
|
|
|
};
|
|
|
|
} while (maj_stat & GSS_S_CONTINUE_NEEDED);
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Whenever the routine returns a major status that includes the value
|
|
|
|
.Dv GSS_S_CONTINUE_NEEDED , the context is not fully established and the
|
|
|
|
following restrictions apply to the output parameters:
|
|
|
|
.Pp
|
|
|
|
The value returned via the
|
|
|
|
.Fa time_rec
|
2010-08-16 15:18:30 +00:00
|
|
|
parameter is undefined unless the
|
2005-12-29 14:40:22 +00:00
|
|
|
accompanying
|
|
|
|
.Fa ret_flags
|
|
|
|
parameter contains the bit
|
|
|
|
.Dv GSS_C_PROT_READY_FLAG , indicating that per-message services may be
|
|
|
|
applied in advance of a successful completion status, the value
|
|
|
|
returned via the
|
|
|
|
.Fa mech_type
|
|
|
|
parameter may be undefined until the
|
|
|
|
routine returns a major status value of
|
|
|
|
.Dv GSS_S_COMPLETE .
|
|
|
|
.Pp
|
|
|
|
The values of the
|
|
|
|
.Dv GSS_C_DELEG_FLAG ,
|
|
|
|
.Dv GSS_C_MUTUAL_FLAG ,
|
|
|
|
.Dv GSS_C_REPLAY_FLAG ,
|
|
|
|
.Dv GSS_C_SEQUENCE_FLAG ,
|
|
|
|
.Dv GSS_C_CONF_FLAG ,
|
|
|
|
.Dv GSS_C_INTEG_FLAG
|
|
|
|
and
|
|
|
|
.Dv GSS_C_ANON_FLAG bits returned
|
|
|
|
via the
|
|
|
|
.Fa ret_flags
|
|
|
|
parameter should contain the values that the
|
|
|
|
implementation expects would be valid if context establishment were
|
|
|
|
to succeed.
|
|
|
|
.Pp
|
|
|
|
The values of the
|
|
|
|
.Dv GSS_C_PROT_READY_FLAG
|
|
|
|
and
|
|
|
|
.Dv GSS_C_TRANS_FLAG bits
|
|
|
|
within
|
|
|
|
.Fa ret_flags
|
|
|
|
should indicate the actual state at the time
|
|
|
|
.Fn gss_accept_sec_context
|
|
|
|
returns, whether or not the context is fully established.
|
|
|
|
.Pp
|
|
|
|
Although this requires that GSS-API implementations set the
|
|
|
|
.Dv GSS_C_PROT_READY_FLAG
|
|
|
|
in the final
|
|
|
|
.Fa ret_flags
|
|
|
|
returned to a caller
|
|
|
|
(i.e. when accompanied by a
|
|
|
|
.Dv GSS_S_COMPLETE
|
|
|
|
status code), applications
|
|
|
|
should not rely on this behavior as the flag was not defined in
|
|
|
|
Version 1 of the GSS-API. Instead, applications should be prepared to
|
|
|
|
use per-message services after a successful context establishment,
|
|
|
|
according to the
|
|
|
|
.Dv GSS_C_INTEG_FLAG
|
|
|
|
and
|
|
|
|
.Dv GSS_C_CONF_FLAG values.
|
|
|
|
.Pp
|
|
|
|
All other bits within the
|
|
|
|
.Fa ret_flags
|
|
|
|
argument should be set to zero.
|
|
|
|
While the routine returns
|
|
|
|
.Dv GSS_S_CONTINUE_NEEDED , the values returned
|
|
|
|
via the
|
|
|
|
.Fa ret_flags
|
|
|
|
argument indicate the services that the
|
|
|
|
implementation expects to be available from the established context.
|
|
|
|
.Pp
|
|
|
|
If the initial call of
|
|
|
|
.Fn gss_accept_sec_context
|
|
|
|
fails, the
|
|
|
|
implementation should not create a context object, and should leave
|
|
|
|
the value of the context_handle parameter set to
|
|
|
|
.Dv GSS_C_NO_CONTEXT to
|
|
|
|
indicate this. In the event of a failure on a subsequent call, the
|
|
|
|
implementation is permitted to delete the "half-built" security
|
|
|
|
context (in which case it should set the
|
|
|
|
.Fa context_handle
|
|
|
|
parameter to
|
|
|
|
.Dv GSS_C_NO_CONTEXT ), but the preferred behavior is to leave the
|
|
|
|
security context (and the context_handle parameter) untouched for the
|
|
|
|
application to delete (using
|
|
|
|
.Xr gss_delete_sec_context 3 ).
|
|
|
|
.Pp
|
|
|
|
During context establishment, the informational status bits
|
|
|
|
.Dv GSS_S_OLD_TOKEN
|
|
|
|
and
|
|
|
|
.Dv GSS_S_DUPLICATE_TOKEN
|
|
|
|
indicate fatal errors, and
|
|
|
|
GSS-API mechanisms should always return them in association with a
|
|
|
|
routine error of
|
|
|
|
.Dv GSS_S_FAILURE . This requirement for pairing did not
|
|
|
|
exist in version 1 of the GSS-API specification, so applications that
|
|
|
|
wish to run over version 1 implementations must special-case these
|
|
|
|
codes.
|
|
|
|
.Sh PARAMETERS
|
2012-06-08 12:09:00 +00:00
|
|
|
.Bl -tag -width ".It input_chan_bindings"
|
2005-12-29 14:40:22 +00:00
|
|
|
.It context_handle
|
|
|
|
Context handle for new context.
|
|
|
|
Supply
|
|
|
|
.Dv GSS_C_NO_CONTEXT for first
|
|
|
|
call; use value returned in subsequent calls.
|
|
|
|
Once
|
|
|
|
.Fn gss_accept_sec_context
|
|
|
|
has returned a
|
|
|
|
value via this parameter, resources have been
|
|
|
|
assigned to the corresponding context, and must
|
|
|
|
be freed by the application after use with a
|
|
|
|
call to
|
|
|
|
.Xr gss_delete_sec_context 3 .
|
|
|
|
.It acceptor_cred_handle
|
|
|
|
Credential handle claimed by context acceptor.
|
|
|
|
Specify
|
|
|
|
.Dv GSS_C_NO_CREDENTIAL to accept the context as a
|
|
|
|
default principal.
|
|
|
|
If
|
|
|
|
.Dv GSS_C_NO_CREDENTIAL is
|
|
|
|
specified, but no default acceptor principal is
|
|
|
|
defined,
|
|
|
|
.Dv GSS_S_NO_CRED will be returned.
|
|
|
|
.It input_token_buffer
|
|
|
|
Token obtained from remote application.
|
|
|
|
.It input_chan_bindings
|
|
|
|
Application-specified bindings.
|
|
|
|
Allows application to securely bind channel identification information
|
|
|
|
to the security context.
|
|
|
|
If channel bindings are not used, specify
|
|
|
|
.Dv GSS_C_NO_CHANNEL_BINDINGS .
|
|
|
|
.It src_name
|
|
|
|
Authenticated name of context initiator.
|
|
|
|
After use, this name should be deallocated by passing it to
|
|
|
|
.Xr gss_release_name 3 .
|
|
|
|
If not required, specify
|
|
|
|
.Dv NULL .
|
|
|
|
.It mech_type
|
|
|
|
Security mechanism used.
|
|
|
|
The returned OID value will be a pointer into static storage,
|
|
|
|
and should be treated as read-only by the caller
|
|
|
|
(in particular, it does not need to be freed).
|
|
|
|
If not required, specify
|
|
|
|
.Dv NULL .
|
|
|
|
.It output_token
|
|
|
|
Token to be passed to peer application.
|
|
|
|
If the length field of the returned token buffer is 0,
|
|
|
|
then no token need be passed to the peer application.
|
|
|
|
If a non-zero length field is returned,
|
|
|
|
the associated storage must be freed after use by the
|
|
|
|
application with a call to
|
|
|
|
.Xr gss_release_buffer 3 .
|
|
|
|
.It ret_flags
|
|
|
|
Contains various independent flags,
|
|
|
|
each of which indicates that the context supports a specific service option.
|
|
|
|
If not needed, specify
|
|
|
|
.Dv NULL .
|
|
|
|
Symbolic names are provided for each flag,
|
|
|
|
and the symbolic names corresponding to the required flags should be
|
|
|
|
logically-ANDed with the
|
|
|
|
.Fa ret_flags
|
|
|
|
value to test whether a given option is supported by the context.
|
|
|
|
The flags are:
|
|
|
|
.Bl -tag -width "WW"
|
|
|
|
.It GSS_C_DELEG_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
Delegated credentials are available via the delegated_cred_handle parameter
|
|
|
|
.It False
|
|
|
|
No credentials were delegated
|
|
|
|
.El
|
|
|
|
.It GSS_C_MUTUAL_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
Remote peer asked for mutual authentication
|
|
|
|
.It False
|
|
|
|
Remote peer did not ask for mutual authentication
|
|
|
|
.El
|
|
|
|
.It GSS_C_REPLAY_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
Replay of protected messages will be detected
|
|
|
|
.It False
|
|
|
|
Replayed messages will not be detected
|
|
|
|
.El
|
|
|
|
.It GSS_C_SEQUENCE_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
Out-of-sequence protected messages will be detected
|
|
|
|
.It False
|
|
|
|
Out-of-sequence messages will not be detected
|
|
|
|
.El
|
|
|
|
.It GSS_C_CONF_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
Confidentiality service may be invoked by calling the
|
|
|
|
.Xr gss_wrap 3
|
|
|
|
routine
|
|
|
|
.It False
|
|
|
|
No confidentiality service (via
|
|
|
|
.Xr gss_wrap 3 )
|
|
|
|
available.
|
|
|
|
.Xr gss_wrap 3
|
|
|
|
will provide message encapsulation,
|
|
|
|
data-origin authentication and integrity services only.
|
|
|
|
.El
|
|
|
|
.It GSS_C_INTEG_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
Integrity service may be invoked by calling either
|
|
|
|
.Xr gss_get_mic 3
|
|
|
|
or
|
|
|
|
.Xr gss_wrap 3
|
|
|
|
routines.
|
|
|
|
.It False
|
|
|
|
Per-message integrity service unavailable.
|
|
|
|
.El
|
|
|
|
.It GSS_C_ANON_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
The initiator does not wish to be authenticated; the
|
|
|
|
.Fa src_name
|
|
|
|
parameter (if requested) contains an anonymous internal name.
|
|
|
|
.It False
|
|
|
|
The initiator has been authenticated normally.
|
|
|
|
.El
|
|
|
|
.It GSS_C_PROT_READY_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
Protection services (as specified by the states of the
|
|
|
|
.Dv GSS_C_CONF_FLAG
|
|
|
|
and
|
|
|
|
.Dv GSS_C_INTEG_FLAG )
|
|
|
|
are available if the accompanying major status return value is either
|
|
|
|
.Dv GSS_S_COMPLETE
|
|
|
|
or
|
|
|
|
.Dv GSS_S_CONTINUE_NEEDED.
|
|
|
|
.It False
|
|
|
|
Protection services (as specified by the states of the
|
|
|
|
.Dv GSS_C_CONF_FLAG
|
|
|
|
and
|
|
|
|
.Dv GSS_C_INTEG_FLAG )
|
|
|
|
are available only if the accompanying major status return value is
|
|
|
|
.Dv GSS_S_COMPLETE .
|
|
|
|
.El
|
|
|
|
.It GSS_C_TRANS_FLAG
|
|
|
|
.Bl -tag -width "False"
|
|
|
|
.It True
|
|
|
|
The resultant security context may be transferred to other processes
|
|
|
|
via a call to
|
|
|
|
.Xr gss_export_sec_context 3 .
|
|
|
|
.It False
|
|
|
|
The security context is not transferable.
|
|
|
|
.El
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
All other bits should be set to zero.
|
|
|
|
.It time_rec
|
|
|
|
Number of seconds for which the context will remain valid.
|
|
|
|
Specify
|
|
|
|
.Dv NULL
|
|
|
|
if not required.
|
|
|
|
.It delegated_cred_handle
|
|
|
|
Credential
|
|
|
|
handle for credentials received from context initiator.
|
|
|
|
Only valid if
|
|
|
|
.Dv GSS_C_DELEG_FLAG
|
|
|
|
in
|
|
|
|
.Fa ret_flags
|
|
|
|
is true,
|
|
|
|
in which case an explicit credential handle
|
|
|
|
(i.e. not
|
|
|
|
.Dv GSS_C_NO_CREDENTIAL )
|
|
|
|
will be returned; if false,
|
|
|
|
.Fn gss_accept_context
|
|
|
|
will set this parameter to
|
|
|
|
.Dv GSS_C_NO_CREDENTIAL .
|
|
|
|
If a credential handle is returned,
|
|
|
|
the associated resources must be released by the application after use
|
|
|
|
with a call to
|
|
|
|
.Xr gss_release_cred 3 .
|
|
|
|
Specify
|
|
|
|
.Dv NULL if not required.
|
|
|
|
.It minor_status
|
|
|
|
Mechanism specific status code.
|
|
|
|
.El
|
|
|
|
.Sh RETURN VALUES
|
2012-06-08 12:09:00 +00:00
|
|
|
.Bl -tag -width ".It GSS_S_DEFECTIVE_CREDENTIAL"
|
2005-12-29 14:40:22 +00:00
|
|
|
.It GSS_S_CONTINUE_NEEDED
|
|
|
|
Indicates that a token from the peer application is required to
|
|
|
|
complete the context,
|
|
|
|
and that gss_accept_sec_context must be called again with that token.
|
|
|
|
.It GSS_S_DEFECTIVE_TOKEN
|
|
|
|
Indicates that consistency checks performed on the input_token failed.
|
|
|
|
.It GSS_S_DEFECTIVE_CREDENTIAL
|
|
|
|
Indicates that consistency checks performed on the credential failed.
|
|
|
|
.It GSS_S_NO_CRED
|
|
|
|
The supplied credentials were not valid for context acceptance,
|
|
|
|
or the credential handle did not reference any credentials.
|
|
|
|
.It GSS_S_CREDENTIALS_EXPIRED
|
|
|
|
The referenced credentials have expired.
|
|
|
|
.It GSS_S_BAD_BINDINGS
|
|
|
|
The input_token contains different channel bindings to those specified via the
|
|
|
|
input_chan_bindings parameter.
|
|
|
|
.It GSS_S_NO_CONTEXT
|
|
|
|
Indicates that the supplied context handle did not refer to a valid context.
|
|
|
|
.It GSS_S_BAD_SIG
|
|
|
|
The input_token contains an invalid MIC.
|
|
|
|
.It GSS_S_OLD_TOKEN
|
|
|
|
The input_token was too old.
|
|
|
|
This is a fatal error during context establishment.
|
|
|
|
.It GSS_S_DUPLICATE_TOKEN
|
|
|
|
The input_token is valid,
|
|
|
|
but is a duplicate of a token already processed.
|
|
|
|
This is a fatal error during context establishment.
|
|
|
|
.It GSS_S_BAD_MECH
|
|
|
|
The received token specified a mechanism that is not supported by
|
|
|
|
the implementation or the provided credential.
|
|
|
|
.El
|
|
|
|
.Sh SEE ALSO
|
|
|
|
.Xr gss_delete_sec_context 3 ,
|
|
|
|
.Xr gss_export_sec_context 3 ,
|
|
|
|
.Xr gss_get_mic 3 ,
|
|
|
|
.Xr gss_init_sec_context 3 ,
|
|
|
|
.Xr gss_release_buffer 3 ,
|
|
|
|
.Xr gss_release_cred 3 ,
|
|
|
|
.Xr gss_release_name 3 ,
|
|
|
|
.Xr gss_wrap 3
|
|
|
|
.Sh STANDARDS
|
2012-06-08 12:09:00 +00:00
|
|
|
.Bl -tag -width ".It RFC 2743"
|
2005-12-29 14:40:22 +00:00
|
|
|
.It RFC 2743
|
|
|
|
Generic Security Service Application Program Interface Version 2, Update 1
|
|
|
|
.It RFC 2744
|
|
|
|
Generic Security Service API Version 2 : C-bindings
|
|
|
|
.El
|
|
|
|
.Sh HISTORY
|
|
|
|
The
|
|
|
|
.Nm
|
2010-01-26 15:03:33 +00:00
|
|
|
function first appeared in
|
2005-12-29 14:40:22 +00:00
|
|
|
.Fx 7.0 .
|
|
|
|
.Sh AUTHORS
|
|
|
|
John Wray, Iris Associates
|
2006-01-25 10:06:28 +00:00
|
|
|
.Sh COPYRIGHT
|
|
|
|
Copyright (C) The Internet Society (2000). All Rights Reserved.
|
|
|
|
.Pp
|
|
|
|
This document and translations of it may be copied and furnished to
|
|
|
|
others, and derivative works that comment on or otherwise explain it
|
|
|
|
or assist in its implementation may be prepared, copied, published
|
|
|
|
and distributed, in whole or in part, without restriction of any
|
|
|
|
kind, provided that the above copyright notice and this paragraph are
|
|
|
|
included on all such copies and derivative works. However, this
|
|
|
|
document itself may not be modified in any way, such as by removing
|
|
|
|
the copyright notice or references to the Internet Society or other
|
|
|
|
Internet organizations, except as needed for the purpose of
|
|
|
|
developing Internet standards in which case the procedures for
|
|
|
|
copyrights defined in the Internet Standards process must be
|
|
|
|
followed, or as required to translate it into languages other than
|
|
|
|
English.
|
|
|
|
.Pp
|
|
|
|
The limited permissions granted above are perpetual and will not be
|
|
|
|
revoked by the Internet Society or its successors or assigns.
|
|
|
|
.Pp
|
|
|
|
This document and the information contained herein is provided on an
|
|
|
|
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
|
|
|
|
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
|
|
|
|
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
|
|
|
|
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
|
|
|
|
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
|