1/*
2 * Copyright (c) 1997 - 2003 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 the Institute nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include "krb5_locl.h"
35
36static krb5_error_code
37make_etypelist(krb5_context context,
38	       krb5_authdata **auth_data)
39{
40    EtypeList etypes;
41    krb5_error_code ret;
42    krb5_authdata ad;
43    u_char *buf;
44    size_t len = 0;
45    size_t buf_size;
46
47    ret = _krb5_init_etype(context, KRB5_PDU_NONE,
48			   &etypes.len, &etypes.val,
49			   NULL);
50    if (ret)
51	return ret;
52
53    ASN1_MALLOC_ENCODE(EtypeList, buf, buf_size, &etypes, &len, ret);
54    if (ret) {
55	free_EtypeList(&etypes);
56	return ret;
57    }
58    if(buf_size != len)
59	krb5_abortx(context, "internal error in ASN.1 encoder");
60    free_EtypeList(&etypes);
61
62    ALLOC_SEQ(&ad, 1);
63    if (ad.val == NULL) {
64	free(buf);
65	krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
66	return ENOMEM;
67    }
68
69    ad.val[0].ad_type = KRB5_AUTHDATA_GSS_API_ETYPE_NEGOTIATION;
70    ad.val[0].ad_data.length = len;
71    ad.val[0].ad_data.data = buf;
72
73    ASN1_MALLOC_ENCODE(AD_IF_RELEVANT, buf, buf_size, &ad, &len, ret);
74    if (ret) {
75	free_AuthorizationData(&ad);
76	return ret;
77    }
78    if(buf_size != len)
79	krb5_abortx(context, "internal error in ASN.1 encoder");
80    free_AuthorizationData(&ad);
81
82    ALLOC(*auth_data, 1);
83    if (*auth_data == NULL) {
84        free(buf);
85	krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
86	return ENOMEM;
87    }
88
89    ALLOC_SEQ(*auth_data, 1);
90    if ((*auth_data)->val == NULL) {
91        free(*auth_data);
92	free(buf);
93	krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
94	return ENOMEM;
95    }
96
97    (*auth_data)->val[0].ad_type = KRB5_AUTHDATA_IF_RELEVANT;
98    (*auth_data)->val[0].ad_data.length = len;
99    (*auth_data)->val[0].ad_data.data = buf;
100
101    return 0;
102}
103
104KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
105_krb5_build_authenticator (krb5_context context,
106			   krb5_auth_context auth_context,
107			   krb5_enctype enctype,
108			   krb5_creds *cred,
109			   Checksum *cksum,
110			   krb5_data *result,
111			   krb5_key_usage usage)
112{
113    Authenticator auth;
114    u_char *buf = NULL;
115    size_t buf_size;
116    size_t len = 0;
117    krb5_error_code ret;
118    krb5_crypto crypto;
119
120    memset(&auth, 0, sizeof(auth));
121
122    auth.authenticator_vno = 5;
123    copy_Realm(&cred->client->realm, &auth.crealm);
124    copy_PrincipalName(&cred->client->name, &auth.cname);
125
126    krb5_us_timeofday (context, &auth.ctime, &auth.cusec);
127
128    ret = krb5_auth_con_getlocalsubkey(context, auth_context, &auth.subkey);
129    if(ret)
130	goto fail;
131
132    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
133	if(auth_context->local_seqnumber == 0)
134	    krb5_generate_seq_number (context,
135				      &cred->session,
136				      &auth_context->local_seqnumber);
137	ALLOC(auth.seq_number, 1);
138	if(auth.seq_number == NULL) {
139	    ret = ENOMEM;
140	    goto fail;
141	}
142	*auth.seq_number = auth_context->local_seqnumber;
143    } else
144	auth.seq_number = NULL;
145    auth.authorization_data = NULL;
146
147    if (cksum) {
148	ALLOC(auth.cksum, 1);
149	if (auth.cksum == NULL) {
150	    ret = ENOMEM;
151	    goto fail;
152	}
153	ret = copy_Checksum(cksum, auth.cksum);
154	if (ret)
155	    goto fail;
156
157	if (auth.cksum->cksumtype == CKSUMTYPE_GSSAPI) {
158	    /*
159	     * This is not GSS-API specific, we only enable it for
160	     * GSS for now
161	     */
162	    ret = make_etypelist(context, &auth.authorization_data);
163	    if (ret)
164		goto fail;
165	}
166    }
167
168    /* XXX - Copy more to auth_context? */
169
170    auth_context->authenticator->ctime = auth.ctime;
171    auth_context->authenticator->cusec = auth.cusec;
172
173    ASN1_MALLOC_ENCODE(Authenticator, buf, buf_size, &auth, &len, ret);
174    if (ret)
175	goto fail;
176    if(buf_size != len)
177	krb5_abortx(context, "internal error in ASN.1 encoder");
178
179    ret = krb5_crypto_init(context, &cred->session, enctype, &crypto);
180    if (ret)
181	goto fail;
182    ret = krb5_encrypt (context,
183			crypto,
184			usage /* KRB5_KU_AP_REQ_AUTH */,
185			buf,
186			len,
187			result);
188    krb5_crypto_destroy(context, crypto);
189
190    if (ret)
191	goto fail;
192
193 fail:
194    free_Authenticator (&auth);
195    free (buf);
196
197    return ret;
198}
199