xref: /freebsd/crypto/heimdal/lib/gssapi/mech/gss_init_sec_context.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1 /*-
2  * Copyright (c) 2005 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
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.
13  *
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
24  * SUCH DAMAGE.
25  *
26  *	$FreeBSD: src/lib/libgssapi/gss_init_sec_context.c,v 1.1 2005/12/29 14:40:20 dfr Exp $
27  */
28 
29 #include "mech_locl.h"
30 
31 static gss_cred_id_t
32 _gss_mech_cred_find(gss_cred_id_t cred_handle, gss_OID mech_type)
33 {
34 	struct _gss_cred *cred = (struct _gss_cred *)cred_handle;
35 	struct _gss_mechanism_cred *mc;
36 
37 	if (cred == NULL)
38 		return GSS_C_NO_CREDENTIAL;
39 
40 	HEIM_SLIST_FOREACH(mc, &cred->gc_mc, gmc_link) {
41 		if (gss_oid_equal(mech_type, mc->gmc_mech_oid))
42 			return mc->gmc_cred;
43 	}
44 	return GSS_C_NO_CREDENTIAL;
45 }
46 
47 /**
48  * As the initiator build a context with an acceptor.
49  *
50  * Returns in the major
51  * - GSS_S_COMPLETE - if the context if build
52  * - GSS_S_CONTINUE_NEEDED -  if the caller needs  to continue another
53  *	round of gss_i nit_sec_context
54  * - error code - any other error code
55  *
56  * @param minor_status minor status code.
57  *
58  * @param initiator_cred_handle the credential to use when building
59  *        the context, if GSS_C_NO_CREDENTIAL is passed, the default
60  *        credential for the mechanism will be used.
61  *
62  * @param context_handle a pointer to a context handle, will be
63  * 	  returned as long as there is not an error.
64  *
65  * @param target_name the target name of acceptor, created using
66  * 	  gss_import_name(). The name is can be of any name types the
67  * 	  mechanism supports, check supported name types with
68  * 	  gss_inquire_names_for_mech().
69  *
70  * @param input_mech_type mechanism type to use, if GSS_C_NO_OID is
71  *        used, Kerberos (GSS_KRB5_MECHANISM) will be tried. Other
72  *        available mechanism are listed in the @ref gssapi_mechs_intro
73  *        section.
74  *
75  * @param req_flags flags using when building the context, see @ref
76  *        gssapi_context_flags
77  *
78  * @param time_req time requested this context should be valid in
79  *        seconds, common used value is GSS_C_INDEFINITE
80  *
81  * @param input_chan_bindings Channel bindings used, if not exepected
82  *        otherwise, used GSS_C_NO_CHANNEL_BINDINGS
83  *
84  * @param input_token input token sent from the acceptor, for the
85  * 	  initial packet the buffer of { NULL, 0 } should be used.
86  *
87  * @param actual_mech_type the actual mech used, MUST NOT be freed
88  *        since it pointing to static memory.
89  *
90  * @param output_token if there is an output token, regardless of
91  * 	  complete, continue_needed, or error it should be sent to the
92  * 	  acceptor
93  *
94  * @param ret_flags return what flags was negotitated, caller should
95  * 	  check if they are accetable. For example, if
96  * 	  GSS_C_MUTUAL_FLAG was negotiated with the acceptor or not.
97  *
98  * @param time_rec amount of time this context is valid for
99  *
100  * @returns a gss_error code, see gss_display_status() about printing
101  *          the error code.
102  *
103  * @ingroup gssapi
104  */
105 
106 
107 
108 GSSAPI_LIB_FUNCTION OM_uint32 GSSAPI_LIB_CALL
109 gss_init_sec_context(OM_uint32 * minor_status,
110     const gss_cred_id_t initiator_cred_handle,
111     gss_ctx_id_t * context_handle,
112     const gss_name_t target_name,
113     const gss_OID input_mech_type,
114     OM_uint32 req_flags,
115     OM_uint32 time_req,
116     const gss_channel_bindings_t input_chan_bindings,
117     const gss_buffer_t input_token,
118     gss_OID * actual_mech_type,
119     gss_buffer_t output_token,
120     OM_uint32 * ret_flags,
121     OM_uint32 * time_rec)
122 {
123 	OM_uint32 major_status;
124 	gssapi_mech_interface m;
125 	struct _gss_name *name = (struct _gss_name *) target_name;
126 	struct _gss_mechanism_name *mn;
127 	struct _gss_context *ctx = (struct _gss_context *) *context_handle;
128 	gss_cred_id_t cred_handle;
129 	int allocated_ctx;
130 	gss_OID mech_type = input_mech_type;
131 
132 	*minor_status = 0;
133 
134 	_mg_buffer_zero(output_token);
135 	if (actual_mech_type)
136 	    *actual_mech_type = GSS_C_NO_OID;
137 	if (ret_flags)
138 	    *ret_flags = 0;
139 	if (time_rec)
140 	    *time_rec = 0;
141 
142 	/*
143 	 * If we haven't allocated a context yet, do so now and lookup
144 	 * the mechanism switch table. If we have one already, make
145 	 * sure we use the same mechanism switch as before.
146 	 */
147 	if (!ctx) {
148 		if (mech_type == NULL)
149 			mech_type = GSS_KRB5_MECHANISM;
150 
151 		ctx = malloc(sizeof(struct _gss_context));
152 		if (!ctx) {
153 			*minor_status = ENOMEM;
154 			return (GSS_S_FAILURE);
155 		}
156 		memset(ctx, 0, sizeof(struct _gss_context));
157 		m = ctx->gc_mech = __gss_get_mechanism(mech_type);
158 		if (!m) {
159 			free(ctx);
160 			return (GSS_S_BAD_MECH);
161 		}
162 		allocated_ctx = 1;
163 	} else {
164 		m = ctx->gc_mech;
165 		mech_type = &ctx->gc_mech->gm_mech_oid;
166 		allocated_ctx = 0;
167 	}
168 
169 	/*
170 	 * Find the MN for this mechanism.
171 	 */
172 	major_status = _gss_find_mn(minor_status, name, mech_type, &mn);
173 	if (major_status != GSS_S_COMPLETE) {
174 		if (allocated_ctx)
175 			free(ctx);
176 		return major_status;
177 	}
178 
179 	/*
180 	 * If we have a cred, find the cred for this mechanism.
181 	 */
182 	if (m->gm_flags & GM_USE_MG_CRED)
183 		cred_handle = initiator_cred_handle;
184 	else
185 		cred_handle = _gss_mech_cred_find(initiator_cred_handle, mech_type);
186 
187 	major_status = m->gm_init_sec_context(minor_status,
188 	    cred_handle,
189 	    &ctx->gc_ctx,
190 	    mn->gmn_name,
191 	    mech_type,
192 	    req_flags,
193 	    time_req,
194 	    input_chan_bindings,
195 	    input_token,
196 	    actual_mech_type,
197 	    output_token,
198 	    ret_flags,
199 	    time_rec);
200 
201 	if (major_status != GSS_S_COMPLETE
202 	    && major_status != GSS_S_CONTINUE_NEEDED) {
203 		if (allocated_ctx)
204 			free(ctx);
205 		_mg_buffer_zero(output_token);
206 		_gss_mg_error(m, major_status, *minor_status);
207 	} else {
208 		*context_handle = (gss_ctx_id_t) ctx;
209 	}
210 
211 	return (major_status);
212 }
213