1 /* $OpenBSD: ssh-pkcs11-helper.c,v 1.3 2010/02/24 06:12:53 djm Exp $ */
3 * Copyright (c) 2010 Markus Friedl. All rights reserved.
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 #include <sys/types.h>
21 #ifdef HAVE_SYS_TIME_H
22 # include <sys/time.h>
25 #include "openbsd-compat/sys-queue.h"
38 #include "ssh-pkcs11.h"
42 /* borrows code from sftp-server and ssh-agent */
44 struct pkcs11_keyinfo {
47 TAILQ_ENTRY(pkcs11_keyinfo) next;
50 TAILQ_HEAD(, pkcs11_keyinfo) pkcs11_keylist;
52 #define MAX_MSG_LENGTH 10240 /*XXX*/
55 #define get_int() buffer_get_int(&iqueue);
56 #define get_string(lenp) buffer_get_string(&iqueue, lenp);
58 /* input and output queue */
63 add_key(Key *k, char *name)
65 struct pkcs11_keyinfo *ki;
67 ki = xcalloc(1, sizeof(*ki));
68 ki->providername = xstrdup(name);
70 TAILQ_INSERT_TAIL(&pkcs11_keylist, ki, next);
74 del_keys_by_name(char *name)
76 struct pkcs11_keyinfo *ki, *nxt;
78 for (ki = TAILQ_FIRST(&pkcs11_keylist); ki; ki = nxt) {
79 nxt = TAILQ_NEXT(ki, next);
80 if (!strcmp(ki->providername, name)) {
81 TAILQ_REMOVE(&pkcs11_keylist, ki, next);
82 xfree(ki->providername);
89 /* lookup matching 'private' key */
93 struct pkcs11_keyinfo *ki;
95 TAILQ_FOREACH(ki, &pkcs11_keylist, next) {
96 debug("check %p %s", ki, ki->providername);
97 if (key_equal(k, ki->key))
106 int mlen = buffer_len(m);
108 buffer_put_int(&oqueue, mlen);
109 buffer_append(&oqueue, buffer_ptr(m), mlen);
110 buffer_consume(m, mlen);
124 name = get_string(NULL);
125 pin = get_string(NULL);
126 if ((nkeys = pkcs11_add_provider(name, pin, &keys)) > 0) {
127 buffer_put_char(&msg, SSH2_AGENT_IDENTITIES_ANSWER);
128 buffer_put_int(&msg, nkeys);
129 for (i = 0; i < nkeys; i++) {
130 key_to_blob(keys[i], &blob, &blen);
131 buffer_put_string(&msg, blob, blen);
132 buffer_put_cstring(&msg, name);
134 add_key(keys[i], name);
138 buffer_put_char(&msg, SSH_AGENT_FAILURE);
153 name = get_string(NULL);
154 pin = get_string(NULL);
155 del_keys_by_name(name);
156 if (pkcs11_del_provider(name) == 0)
157 buffer_put_char(&msg, SSH_AGENT_SUCCESS);
159 buffer_put_char(&msg, SSH_AGENT_FAILURE);
169 u_char *blob, *data, *signature = NULL;
170 u_int blen, dlen, slen = 0;
171 int ok = -1, flags, ret;
175 blob = get_string(&blen);
176 data = get_string(&dlen);
177 flags = get_int(); /* XXX ignore */
179 if ((key = key_from_blob(blob, blen)) != NULL) {
180 if ((found = lookup_key(key)) != NULL) {
181 slen = RSA_size(key->rsa);
182 signature = xmalloc(slen);
183 if ((ret = RSA_private_encrypt(dlen, data, signature,
184 found->rsa, RSA_PKCS1_PADDING)) != -1) {
193 buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
194 buffer_put_string(&msg, signature, slen);
196 buffer_put_char(&msg, SSH_AGENT_FAILURE);
200 if (signature != NULL)
215 buf_len = buffer_len(&iqueue);
217 return; /* Incomplete message. */
218 cp = buffer_ptr(&iqueue);
219 msg_len = get_u32(cp);
220 if (msg_len > MAX_MSG_LENGTH) {
221 error("bad message len %d", msg_len);
224 if (buf_len < msg_len + 4)
226 buffer_consume(&iqueue, 4);
228 type = buffer_get_char(&iqueue);
230 case SSH_AGENTC_ADD_SMARTCARD_KEY:
231 debug("process_add");
234 case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
235 debug("process_del");
238 case SSH2_AGENTC_SIGN_REQUEST:
239 debug("process_sign");
243 error("Unknown message %d", type);
246 /* discard the remaining bytes from the current packet */
247 if (buf_len < buffer_len(&iqueue)) {
248 error("iqueue grew unexpectedly");
251 consumed = buf_len - buffer_len(&iqueue);
252 if (msg_len < consumed) {
253 error("msg_len %d < consumed %d", msg_len, consumed);
256 if (msg_len > consumed)
257 buffer_consume(&iqueue, msg_len - consumed);
268 main(int argc, char **argv)
271 int in, out, max, log_stderr = 0;
272 ssize_t len, olen, set_size;
273 SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
274 LogLevel log_level = SYSLOG_LEVEL_ERROR;
278 extern char *__progname;
280 TAILQ_INIT(&pkcs11_keylist);
284 __progname = ssh_get_progname(argv[0]);
286 log_init(__progname, log_level, log_facility, log_stderr);
297 buffer_init(&iqueue);
298 buffer_init(&oqueue);
300 set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
301 rset = (fd_set *)xmalloc(set_size);
302 wset = (fd_set *)xmalloc(set_size);
305 memset(rset, 0, set_size);
306 memset(wset, 0, set_size);
309 * Ensure that we can read a full buffer and handle
310 * the worst-case length packet it can generate,
311 * otherwise apply backpressure by stopping reads.
313 if (buffer_check_alloc(&iqueue, sizeof(buf)) &&
314 buffer_check_alloc(&oqueue, MAX_MSG_LENGTH))
317 olen = buffer_len(&oqueue);
321 if (select(max+1, rset, wset, NULL, NULL) < 0) {
324 error("select: %s", strerror(errno));
328 /* copy stdin to iqueue */
329 if (FD_ISSET(in, rset)) {
330 len = read(in, buf, sizeof buf);
334 } else if (len < 0) {
335 error("read: %s", strerror(errno));
338 buffer_append(&iqueue, buf, len);
341 /* send oqueue to stdout */
342 if (FD_ISSET(out, wset)) {
343 len = write(out, buffer_ptr(&oqueue), olen);
345 error("write: %s", strerror(errno));
348 buffer_consume(&oqueue, len);
353 * Process requests from client if we can fit the results
354 * into the output buffer, otherwise stop processing input
355 * and let the output queue drain.
357 if (buffer_check_alloc(&oqueue, MAX_MSG_LENGTH))
361 #else /* ENABLE_PKCS11 */
363 main(int argc, char **argv)
365 extern char *__progname;
367 __progname = ssh_get_progname(argv[0]);
368 log_init(__progname, SYSLOG_LEVEL_ERROR, SYSLOG_FACILITY_AUTH, 0);
369 fatal("PKCS#11 support disabled at compile time");
371 #endif /* ENABLE_PKCS11 */