recvauth.c revision 259065 
1/*
2 * Copyright (c) 1997-2007 Kungliga Tekniska H��gskolan
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
36/*
37 * See `sendauth.c' for the format.
38 */
39
40static krb5_boolean
41match_exact(const void *data, const char *appl_version)
42{
43    return strcmp(data, appl_version) == 0;
44}
45
46KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
47krb5_recvauth(krb5_context context,
48	      krb5_auth_context *auth_context,
49	      krb5_pointer p_fd,
50	      const char *appl_version,
51	      krb5_principal server,
52	      int32_t flags,
53	      krb5_keytab keytab,
54	      krb5_ticket **ticket)
55{
56    return krb5_recvauth_match_version(context, auth_context, p_fd,
57				       match_exact, appl_version,
58				       server, flags,
59				       keytab, ticket);
60}
61
62KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
63krb5_recvauth_match_version(krb5_context context,
64			    krb5_auth_context *auth_context,
65			    krb5_pointer p_fd,
66			    krb5_boolean (*match_appl_version)(const void *,
67							       const char*),
68			    const void *match_data,
69			    krb5_principal server,
70			    int32_t flags,
71			    krb5_keytab keytab,
72			    krb5_ticket **ticket)
73{
74    krb5_error_code ret;
75    const char *version = KRB5_SENDAUTH_VERSION;
76    char her_version[sizeof(KRB5_SENDAUTH_VERSION)];
77    char *her_appl_version;
78    uint32_t len;
79    u_char repl;
80    krb5_data data;
81    krb5_flags ap_options;
82    ssize_t n;
83
84    /*
85     * If there are no addresses in auth_context, get them from `fd'.
86     */
87
88    if (*auth_context == NULL) {
89	ret = krb5_auth_con_init (context, auth_context);
90	if (ret)
91	    return ret;
92    }
93
94    ret = krb5_auth_con_setaddrs_from_fd (context,
95					  *auth_context,
96					  p_fd);
97    if (ret)
98	return ret;
99
100    if(!(flags & KRB5_RECVAUTH_IGNORE_VERSION)) {
101	n = krb5_net_read (context, p_fd, &len, 4);
102	if (n < 0) {
103	    ret = errno;
104	    krb5_set_error_message(context, ret, "read: %s", strerror(ret));
105	    return ret;
106	}
107	if (n == 0) {
108	    krb5_set_error_message(context, KRB5_SENDAUTH_BADAUTHVERS,
109				   N_("Failed to receive sendauth data", ""));
110	    return KRB5_SENDAUTH_BADAUTHVERS;
111	}
112	len = ntohl(len);
113	if (len != sizeof(her_version)
114	    || krb5_net_read (context, p_fd, her_version, len) != len
115	    || strncmp (version, her_version, len)) {
116	    repl = 1;
117	    krb5_net_write (context, p_fd, &repl, 1);
118	    krb5_clear_error_message (context);
119	    return KRB5_SENDAUTH_BADAUTHVERS;
120	}
121    }
122
123    n = krb5_net_read (context, p_fd, &len, 4);
124    if (n < 0) {
125	ret = errno;
126	krb5_set_error_message(context, ret, "read: %s", strerror(ret));
127	return ret;
128    }
129    if (n == 0) {
130	krb5_clear_error_message (context);
131	return KRB5_SENDAUTH_BADAPPLVERS;
132    }
133    len = ntohl(len);
134    her_appl_version = malloc (len);
135    if (her_appl_version == NULL) {
136	repl = 2;
137	krb5_net_write (context, p_fd, &repl, 1);
138	krb5_set_error_message(context, ENOMEM,
139			       N_("malloc: out of memory", ""));
140	return ENOMEM;
141    }
142    if (krb5_net_read (context, p_fd, her_appl_version, len) != len
143	|| !(*match_appl_version)(match_data, her_appl_version)) {
144	repl = 2;
145	krb5_net_write (context, p_fd, &repl, 1);
146	krb5_set_error_message(context, KRB5_SENDAUTH_BADAPPLVERS,
147			       N_("wrong sendauth version (%s)", ""),
148			       her_appl_version);
149	free (her_appl_version);
150	return KRB5_SENDAUTH_BADAPPLVERS;
151    }
152    free (her_appl_version);
153
154    repl = 0;
155    if (krb5_net_write (context, p_fd, &repl, 1) != 1) {
156	ret = errno;
157	krb5_set_error_message(context, ret, "write: %s", strerror(ret));
158	return ret;
159    }
160
161    krb5_data_zero (&data);
162    ret = krb5_read_message (context, p_fd, &data);
163    if (ret)
164	return ret;
165
166    ret = krb5_rd_req (context,
167		       auth_context,
168		       &data,
169		       server,
170		       keytab,
171		       &ap_options,
172		       ticket);
173    krb5_data_free (&data);
174    if (ret) {
175	krb5_data error_data;
176	krb5_error_code ret2;
177
178	ret2 = krb5_mk_error (context,
179			      ret,
180			      NULL,
181			      NULL,
182			      NULL,
183			      server,
184			      NULL,
185			      NULL,
186			      &error_data);
187	if (ret2 == 0) {
188	    krb5_write_message (context, p_fd, &error_data);
189	    krb5_data_free (&error_data);
190	}
191	return ret;
192    }
193
194    len = 0;
195    if (krb5_net_write (context, p_fd, &len, 4) != 4) {
196	ret = errno;
197	krb5_set_error_message(context, ret, "write: %s", strerror(ret));
198	krb5_free_ticket(context, *ticket);
199	*ticket = NULL;
200	return ret;
201    }
202
203    if (ap_options & AP_OPTS_MUTUAL_REQUIRED) {
204	ret = krb5_mk_rep (context, *auth_context, &data);
205	if (ret) {
206	    krb5_free_ticket(context, *ticket);
207	    *ticket = NULL;
208	    return ret;
209	}
210
211	ret = krb5_write_message (context, p_fd, &data);
212	if (ret) {
213	    krb5_free_ticket(context, *ticket);
214	    *ticket = NULL;
215	    return ret;
216	}
217	krb5_data_free (&data);
218    }
219    return 0;
220}
221