2 * Copyright (c) 2005 Doug Rabson
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/lib/libgssapi/gss_accept_sec_context.c,v 1.1 2005/12/29 14:40:20 dfr Exp $
29 #include "mech_locl.h"
32 parse_header(const gss_buffer_t input_token
, gss_OID mech_oid
)
34 unsigned char *p
= input_token
->value
;
35 size_t len
= input_token
->length
;
39 * Token must start with [APPLICATION 0] SEQUENCE.
40 * But if it doesn't assume it is DCE-STYLE Kerberos!
43 return (GSS_S_DEFECTIVE_TOKEN
);
49 * Decode the length and make sure it agrees with the
53 return (GSS_S_DEFECTIVE_TOKEN
);
54 if ((*p
& 0x80) == 0) {
63 return (GSS_S_DEFECTIVE_TOKEN
);
73 return (GSS_S_DEFECTIVE_TOKEN
);
76 * Decode the OID for the mechanism. Simplify life by
77 * assuming that the OID length is less than 128 bytes.
79 if (len
< 2 || *p
!= 0x06)
80 return (GSS_S_DEFECTIVE_TOKEN
);
81 if ((p
[1] & 0x80) || p
[1] > (len
- 2))
82 return (GSS_S_DEFECTIVE_TOKEN
);
83 mech_oid
->length
= p
[1];
86 mech_oid
->elements
= p
;
88 return GSS_S_COMPLETE
;
91 static gss_OID_desc krb5_mechanism
=
92 {9, rk_UNCONST("\x2a\x86\x48\x86\xf7\x12\x01\x02\x02")};
93 static gss_OID_desc ntlm_mechanism
=
94 {10, rk_UNCONST("\x2b\x06\x01\x04\x01\x82\x37\x02\x02\x0a")};
95 static gss_OID_desc spnego_mechanism
=
96 {6, rk_UNCONST("\x2b\x06\x01\x05\x05\x02")};
99 choose_mech(const gss_buffer_t input
, gss_OID mech_oid
)
104 * First try to parse the gssapi token header and see if it's a
105 * correct header, use that in the first hand.
108 status
= parse_header(input
, mech_oid
);
109 if (status
== GSS_S_COMPLETE
)
110 return GSS_S_COMPLETE
;
113 * Lets guess what mech is really is, callback function to mech ??
116 if (input
->length
> 8 &&
117 memcmp((const char *)input
->value
, "NTLMSSP\x00", 8) == 0)
119 *mech_oid
= ntlm_mechanism
;
120 return GSS_S_COMPLETE
;
121 } else if (input
->length
!= 0 &&
122 ((const char *)input
->value
)[0] == 0x6E)
124 /* Could be a raw AP-REQ (check for APPLICATION tag) */
125 *mech_oid
= krb5_mechanism
;
126 return GSS_S_COMPLETE
;
127 } else if (input
->length
== 0) {
129 * There is the a wierd mode of SPNEGO (in CIFS and
130 * SASL GSS-SPENGO where the first token is zero
131 * length and the acceptor returns a mech_list, lets
132 * hope that is what is happening now.
134 * http://msdn.microsoft.com/en-us/library/cc213114.aspx
135 * "NegTokenInit2 Variation for Server-Initiation"
137 *mech_oid
= spnego_mechanism
;
138 return GSS_S_COMPLETE
;
144 GSSAPI_LIB_FUNCTION OM_uint32 GSSAPI_LIB_CALL
145 gss_accept_sec_context(OM_uint32
*minor_status
,
146 gss_ctx_id_t
*context_handle
,
147 gss_const_cred_id_t acceptor_cred_handle
,
148 const gss_buffer_t input_token
,
149 const gss_channel_bindings_t input_chan_bindings
,
150 gss_name_t
*src_name
,
152 gss_buffer_t output_token
,
153 OM_uint32
*ret_flags
,
155 gss_cred_id_t
*delegated_cred_handle
)
157 OM_uint32 major_status
, mech_ret_flags
, junk
;
158 gssapi_mech_interface m
;
159 struct _gss_context
*ctx
= (struct _gss_context
*) *context_handle
;
160 struct _gss_cred
*cred
= (struct _gss_cred
*) acceptor_cred_handle
;
161 struct _gss_mechanism_cred
*mc
;
162 gss_cred_id_t acceptor_mc
, delegated_mc
;
164 gss_OID mech_ret_type
= NULL
;
168 *src_name
= GSS_C_NO_NAME
;
170 *mech_type
= GSS_C_NO_OID
;
175 if (delegated_cred_handle
)
176 *delegated_cred_handle
= GSS_C_NO_CREDENTIAL
;
177 _mg_buffer_zero(output_token
);
181 * If this is the first call (*context_handle is NULL), we must
182 * parse the input token to figure out the mechanism to use.
184 if (*context_handle
== GSS_C_NO_CONTEXT
) {
185 gss_OID_desc mech_oid
;
187 major_status
= choose_mech(input_token
, &mech_oid
);
188 if (major_status
!= GSS_S_COMPLETE
)
192 * Now that we have a mechanism, we can find the
195 ctx
= malloc(sizeof(struct _gss_context
));
197 *minor_status
= ENOMEM
;
198 return (GSS_S_DEFECTIVE_TOKEN
);
200 memset(ctx
, 0, sizeof(struct _gss_context
));
201 m
= ctx
->gc_mech
= __gss_get_mechanism(&mech_oid
);
204 return (GSS_S_BAD_MECH
);
206 *context_handle
= (gss_ctx_id_t
) ctx
;
212 HEIM_SLIST_FOREACH(mc
, &cred
->gc_mc
, gmc_link
)
213 if (mc
->gmc_mech
== m
)
216 gss_delete_sec_context(&junk
, context_handle
, NULL
);
217 return (GSS_S_BAD_MECH
);
219 acceptor_mc
= mc
->gmc_cred
;
221 acceptor_mc
= GSS_C_NO_CREDENTIAL
;
223 delegated_mc
= GSS_C_NO_CREDENTIAL
;
226 major_status
= m
->gm_accept_sec_context(minor_status
,
237 if (major_status
!= GSS_S_COMPLETE
&&
238 major_status
!= GSS_S_CONTINUE_NEEDED
)
240 _gss_mg_error(m
, major_status
, *minor_status
);
241 gss_delete_sec_context(&junk
, context_handle
, NULL
);
242 return (major_status
);
246 *mech_type
= mech_ret_type
;
248 if (src_name
&& src_mn
) {
250 * Make a new name and mark it as an MN.
252 struct _gss_name
*name
= _gss_make_name(m
, src_mn
);
255 m
->gm_release_name(minor_status
, &src_mn
);
256 gss_delete_sec_context(&junk
, context_handle
, NULL
);
257 return (GSS_S_FAILURE
);
259 *src_name
= (gss_name_t
) name
;
261 m
->gm_release_name(minor_status
, &src_mn
);
264 if (mech_ret_flags
& GSS_C_DELEG_FLAG
) {
265 if (!delegated_cred_handle
) {
266 m
->gm_release_cred(minor_status
, &delegated_mc
);
268 ~(GSS_C_DELEG_FLAG
|GSS_C_DELEG_POLICY_FLAG
);
269 } else if (gss_oid_equal(mech_ret_type
, &m
->gm_mech_oid
) == 0) {
271 * If the returned mech_type is not the same
272 * as the mech, assume its pseudo mech type
273 * and the returned type is already a
276 *delegated_cred_handle
= delegated_mc
;
278 } else if (delegated_mc
) {
279 struct _gss_cred
*dcred
;
280 struct _gss_mechanism_cred
*dmc
;
282 dcred
= malloc(sizeof(struct _gss_cred
));
284 *minor_status
= ENOMEM
;
285 gss_delete_sec_context(&junk
, context_handle
, NULL
);
286 return (GSS_S_FAILURE
);
288 HEIM_SLIST_INIT(&dcred
->gc_mc
);
289 dmc
= malloc(sizeof(struct _gss_mechanism_cred
));
292 *minor_status
= ENOMEM
;
293 gss_delete_sec_context(&junk
, context_handle
, NULL
);
294 return (GSS_S_FAILURE
);
297 dmc
->gmc_mech_oid
= &m
->gm_mech_oid
;
298 dmc
->gmc_cred
= delegated_mc
;
299 HEIM_SLIST_INSERT_HEAD(&dcred
->gc_mc
, dmc
, gmc_link
);
301 *delegated_cred_handle
= (gss_cred_id_t
) dcred
;
306 *ret_flags
= mech_ret_flags
;
307 return (major_status
);