1 /*
2  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 
7 /*
8  * lib/krb5/krb/mk_priv.c
9  *
10  * Copyright 1990,1991 by the Massachusetts Institute of Technology.
11  * All Rights Reserved.
12  *
13  * Export of this software from the United States of America may
14  *   require a specific license from the United States Government.
15  *   It is the responsibility of any person or organization contemplating
16  *   export to obtain such a license before exporting.
17  *
18  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
19  * distribute this software and its documentation for any purpose and
20  * without fee is hereby granted, provided that the above copyright
21  * notice appear in all copies and that both that copyright notice and
22  * this permission notice appear in supporting documentation, and that
23  * the name of M.I.T. not be used in advertising or publicity pertaining
24  * to distribution of the software without specific, written prior
25  * permission.  Furthermore if you modify this software you must label
26  * your software as modified software and not distribute it in such a
27  * fashion that it might be confused with the original M.I.T. software.
28  * M.I.T. makes no representations about the suitability of
29  * this software for any purpose.  It is provided "as is" without express
30  * or implied warranty.
31  *
32  *
33  * krb5_mk_priv()
34  */
35 
36 #include "k5-int.h"
37 #include "cleanup.h"
38 #include "auth_con.h"
39 
40 /*ARGSUSED*/
41 static krb5_error_code
krb5_mk_priv_basic(krb5_context context,const krb5_data * userdata,const krb5_keyblock * keyblock,krb5_replay_data * replaydata,krb5_address * local_addr,krb5_address * remote_addr,krb5_pointer i_vector,krb5_data * outbuf)42 krb5_mk_priv_basic(krb5_context context, const krb5_data *userdata, const krb5_keyblock *keyblock, krb5_replay_data *replaydata, krb5_address *local_addr, krb5_address *remote_addr, krb5_pointer i_vector, krb5_data *outbuf)
43 {
44     krb5_error_code 	retval;
45     krb5_priv 		privmsg;
46     krb5_priv_enc_part 	privmsg_enc_part;
47     krb5_data 		*scratch1, *scratch2, ivdata;
48     size_t		blocksize, enclen;
49 
50     privmsg.enc_part.kvno = 0;	/* XXX allow user-set? */
51     privmsg.enc_part.enctype = keyblock->enctype;
52 
53     privmsg_enc_part.user_data = *userdata;
54     privmsg_enc_part.s_address = local_addr;
55     privmsg_enc_part.r_address = remote_addr;
56 
57     /* We should check too make sure one exists. */
58     privmsg_enc_part.timestamp  = replaydata->timestamp;
59     privmsg_enc_part.usec 	= replaydata->usec;
60     privmsg_enc_part.seq_number = replaydata->seq;
61 
62     /* start by encoding to-be-encrypted part of the message */
63     if ((retval = encode_krb5_enc_priv_part(&privmsg_enc_part, &scratch1)))
64 	return retval;
65 
66     /* put together an eblock for this encryption */
67     if ((retval = krb5_c_encrypt_length(context, keyblock->enctype,
68 					scratch1->length, &enclen)))
69 	goto clean_scratch;
70 
71     privmsg.enc_part.ciphertext.length = enclen;
72     if (!(privmsg.enc_part.ciphertext.data =
73 	  malloc(privmsg.enc_part.ciphertext.length))) {
74         retval = ENOMEM;
75         goto clean_scratch;
76     }
77 
78     /* call the encryption routine */
79     if (i_vector) {
80 	if ((retval = krb5_c_block_size(context, keyblock->enctype,
81 					&blocksize)))
82 	    goto clean_encpart;
83 
84 	ivdata.length = blocksize;
85 	ivdata.data = i_vector;
86     }
87 
88     if ((retval = krb5_c_encrypt(context, keyblock,
89 				 KRB5_KEYUSAGE_KRB_PRIV_ENCPART,
90 				 i_vector?&ivdata:0,
91 				 scratch1, &privmsg.enc_part)))
92 	goto clean_encpart;
93 
94     if ((retval = encode_krb5_priv(&privmsg, &scratch2)))
95         goto clean_encpart;
96 
97     *outbuf = *scratch2;
98     krb5_xfree(scratch2);
99     retval = 0;
100 
101 clean_encpart:
102     memset(privmsg.enc_part.ciphertext.data, 0,
103 	   privmsg.enc_part.ciphertext.length);
104     free(privmsg.enc_part.ciphertext.data);
105     privmsg.enc_part.ciphertext.length = 0;
106     privmsg.enc_part.ciphertext.data = 0;
107 
108 clean_scratch:
109     memset(scratch1->data, 0, scratch1->length);
110     krb5_free_data(context, scratch1);
111 
112     return retval;
113 }
114 
115 
116 krb5_error_code KRB5_CALLCONV
krb5_mk_priv(krb5_context context,krb5_auth_context auth_context,const krb5_data * userdata,krb5_data * outbuf,krb5_replay_data * outdata)117 krb5_mk_priv(krb5_context context, krb5_auth_context auth_context,
118 	     const krb5_data *userdata, krb5_data *outbuf,
119 	     krb5_replay_data *outdata)
120 {
121     krb5_error_code 	  retval;
122     krb5_keyblock       * keyblock;
123     krb5_replay_data      replaydata;
124 
125     /* Clear replaydata block */
126     memset((char *) &replaydata, 0, sizeof(krb5_replay_data));
127 
128     /* Get keyblock */
129     if ((keyblock = auth_context->send_subkey) == NULL)
130 	keyblock = auth_context->keyblock;
131 
132     /* Get replay info */
133     if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_TIME) &&
134       (auth_context->rcache == NULL))
135 	return KRB5_RC_REQUIRED;
136 
137     if (((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_TIME) ||
138       (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE)) &&
139       (outdata == NULL))
140 	/* Need a better error */
141 	return KRB5_RC_REQUIRED;
142 
143     if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_TIME) ||
144 	(auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_TIME)) {
145 	if ((retval = krb5_us_timeofday(context, &replaydata.timestamp,
146 					&replaydata.usec)))
147 	    return retval;
148 	if (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_TIME) {
149     	    outdata->timestamp = replaydata.timestamp;
150     	    outdata->usec = replaydata.usec;
151 	}
152     }
153     if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) ||
154 	(auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE)) {
155 	replaydata.seq = auth_context->local_seq_number;
156 	if (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
157 	    auth_context->local_seq_number++;
158 	} else {
159     	    outdata->seq = replaydata.seq;
160 	}
161     }
162 
163 {
164     krb5_address * premote_fulladdr = NULL;
165     krb5_address * plocal_fulladdr = NULL;
166     krb5_address remote_fulladdr;
167     krb5_address local_fulladdr;
168     CLEANUP_INIT(2);
169 
170     if (auth_context->local_addr) {
171 	if (auth_context->local_port) {
172 	    if (!(retval = krb5_make_fulladdr(context, auth_context->local_addr,
173 				  	      auth_context->local_port,
174 					      &local_fulladdr))) {
175 	    	CLEANUP_PUSH(local_fulladdr.contents, free);
176 	    	plocal_fulladdr = &local_fulladdr;
177             } else {
178     	    	goto error;
179             }
180 	} else {
181 	    plocal_fulladdr = auth_context->local_addr;
182 	}
183     }
184 
185     if (auth_context->remote_addr) {
186     	if (auth_context->remote_port) {
187 	    if (!(retval = krb5_make_fulladdr(context,auth_context->remote_addr,
188 				 	      auth_context->remote_port,
189 					      &remote_fulladdr))){
190 	    	CLEANUP_PUSH(remote_fulladdr.contents, free);
191 	    	premote_fulladdr = &remote_fulladdr;
192  	    } else {
193 	        CLEANUP_DONE();
194 	        goto error;
195 	    }
196 	} else {
197 	    premote_fulladdr = auth_context->remote_addr;
198 	}
199     }
200 
201     if ((retval = krb5_mk_priv_basic(context, userdata, keyblock, &replaydata,
202 				     plocal_fulladdr, premote_fulladdr,
203 				     auth_context->i_vector, outbuf))) {
204 	CLEANUP_DONE();
205 	goto error;
206     }
207 
208     CLEANUP_DONE();
209 }
210 
211     if (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_TIME) {
212 	krb5_donot_replay replay;
213 
214 	if ((retval = krb5_gen_replay_name(context, auth_context->local_addr,
215 					   "_priv", &replay.client))) {
216     	    krb5_xfree(outbuf);
217 	    goto error;
218 	}
219 
220 	replay.server = "";		/* XXX */
221 	replay.cusec = replaydata.usec;
222 	replay.ctime = replaydata.timestamp;
223 	if ((retval = krb5_rc_store(context, auth_context->rcache, &replay))) {
224 	    /* should we really error out here? XXX */
225     	    krb5_xfree(replay.client);
226 	    goto error;
227 	}
228 	krb5_xfree(replay.client);
229     }
230 
231     return 0;
232 
233 error:
234     if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) ||
235       (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE))
236 	auth_context->local_seq_number--;
237 
238     return retval;
239 }
240 
241