1 /*
2  * Copyright (c) 2009 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of KTH nor the names of its contributors may be
18  *    used to endorse or promote products derived from this software without
19  *    specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY KTH AND ITS CONTRIBUTORS ``AS IS'' AND ANY
22  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL KTH OR ITS CONTRIBUTORS BE
25  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
28  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "mech_locl.h"
35 #include <krb5.h>
36 
37 /*
38  * format: any number of:
39  *     mech-len: int32
40  *     mech-data: char * (not alligned)
41  *     cred-len: int32
42  *     cred-data char * (not alligned)
43 */
44 
45 GSSAPI_LIB_FUNCTION OM_uint32 GSSAPI_LIB_CALL
46 gss_export_cred(OM_uint32 * minor_status,
47 		gss_cred_id_t cred_handle,
48 		gss_buffer_t token)
49 {
50     struct _gss_cred *cred = (struct _gss_cred *)cred_handle;
51     struct _gss_mechanism_cred *mc;
52     gss_buffer_desc buffer;
53     krb5_error_code ret;
54     krb5_storage *sp;
55     OM_uint32 major;
56     krb5_data data;
57 
58     _mg_buffer_zero(token);
59 
60     if (cred == NULL) {
61 	*minor_status = 0;
62 	return GSS_S_NO_CRED;
63     }
64 
65     HEIM_SLIST_FOREACH(mc, &cred->gc_mc, gmc_link) {
66 	if (mc->gmc_mech->gm_export_cred == NULL) {
67 	    *minor_status = 0;
68 	    return GSS_S_NO_CRED;
69 	}
70     }
71 
72     sp = krb5_storage_emem();
73     if (sp == NULL) {
74 	*minor_status = ENOMEM;
75 	return GSS_S_FAILURE;
76     }
77 
78     HEIM_SLIST_FOREACH(mc, &cred->gc_mc, gmc_link) {
79 
80 	major = mc->gmc_mech->gm_export_cred(minor_status,
81 					     mc->gmc_cred, &buffer);
82 	if (major) {
83 	    krb5_storage_free(sp);
84 	    return major;
85 	}
86 
87 	ret = krb5_storage_write(sp, buffer.value, buffer.length);
88 	if (ret < 0 || (size_t)ret != buffer.length) {
89 	    gss_release_buffer(minor_status, &buffer);
90 	    krb5_storage_free(sp);
91 	    *minor_status = EINVAL;
92 	    return GSS_S_FAILURE;
93 	}
94 	gss_release_buffer(minor_status, &buffer);
95     }
96 
97     ret = krb5_storage_to_data(sp, &data);
98     krb5_storage_free(sp);
99     if (ret) {
100 	*minor_status = ret;
101 	return GSS_S_FAILURE;
102     }
103 
104     token->value = data.data;
105     token->length = data.length;
106 
107     return GSS_S_COMPLETE;
108 }
109 
110 GSSAPI_LIB_FUNCTION OM_uint32 GSSAPI_LIB_CALL
111 gss_import_cred(OM_uint32 * minor_status,
112 		gss_buffer_t token,
113 		gss_cred_id_t * cred_handle)
114 {
115     gssapi_mech_interface m;
116     krb5_error_code ret;
117     struct _gss_cred *cred;
118     krb5_storage *sp = NULL;
119     OM_uint32 major, junk;
120     krb5_data data;
121 
122     *cred_handle = GSS_C_NO_CREDENTIAL;
123 
124     if (token->length == 0) {
125 	*minor_status = ENOMEM;
126 	return GSS_S_FAILURE;
127     }
128 
129     sp = krb5_storage_from_readonly_mem(token->value, token->length);
130     if (sp == NULL) {
131 	*minor_status = ENOMEM;
132 	return GSS_S_FAILURE;
133     }
134 
135     cred = calloc(1, sizeof(struct _gss_cred));
136     if (cred == NULL) {
137 	krb5_storage_free(sp);
138 	*minor_status = ENOMEM;
139 	return GSS_S_FAILURE;
140     }
141     HEIM_SLIST_INIT(&cred->gc_mc);
142 
143     *cred_handle = (gss_cred_id_t)cred;
144 
145     while(1) {
146 	struct _gss_mechanism_cred *mc;
147 	gss_buffer_desc buffer;
148 	gss_cred_id_t mcred;
149 	gss_OID_desc oid;
150 
151 	ret = krb5_ret_data(sp, &data);
152 	if (ret == HEIM_ERR_EOF) {
153 	    break;
154 	} else if (ret) {
155 	    *minor_status = ret;
156 	    major = GSS_S_FAILURE;
157 	    goto out;
158 	}
159 	oid.elements = data.data;
160 	oid.length = data.length;
161 
162 	m = __gss_get_mechanism(&oid);
163 	krb5_data_free(&data);
164 	if (!m) {
165 	    *minor_status = 0;
166 	    major = GSS_S_BAD_MECH;
167 	    goto out;
168 	}
169 
170 	if (m->gm_import_cred == NULL) {
171 	    *minor_status = 0;
172 	    major = GSS_S_BAD_MECH;
173 	    goto out;
174 	}
175 
176 	ret = krb5_ret_data(sp, &data);
177 	if (ret) {
178 	    *minor_status = ret;
179 	    major = GSS_S_FAILURE;
180 	    goto out;
181 	}
182 
183 	buffer.value = data.data;
184 	buffer.length = data.length;
185 
186 	major = m->gm_import_cred(minor_status,
187 				  &buffer, &mcred);
188 	krb5_data_free(&data);
189 	if (major) {
190 	    goto out;
191 	}
192 
193 	mc = malloc(sizeof(struct _gss_mechanism_cred));
194 	if (mc == NULL) {
195 	    *minor_status = EINVAL;
196 	    major = GSS_S_FAILURE;
197 	    goto out;
198 	}
199 
200 	mc->gmc_mech = m;
201 	mc->gmc_mech_oid = &m->gm_mech_oid;
202 	mc->gmc_cred = mcred;
203 
204 	HEIM_SLIST_INSERT_HEAD(&cred->gc_mc, mc, gmc_link);
205     }
206     krb5_storage_free(sp);
207     sp = NULL;
208 
209     if (HEIM_SLIST_EMPTY(&cred->gc_mc)) {
210 	major = GSS_S_NO_CRED;
211 	goto out;
212     }
213 
214     return GSS_S_COMPLETE;
215 
216  out:
217     if (sp)
218 	krb5_storage_free(sp);
219 
220     gss_release_cred(&junk, cred_handle);
221 
222     return major;
223 
224 }
225