![[BACK]](/icons/back.gif){kind=icon}
Return to ssh-pkcs11-helper.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh|
Return to ssh-pkcs11-helper.c CVS log | Up to [local] / src / usr.bin / ssh |
1.5 ! dtucker 1: /* $OpenBSD: ssh-pkcs11-helper.c,v 1.4 2012/07/02 12:13:26 dtucker Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 2010 Markus Friedl. All rights reserved.
4: *
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.
8: *
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.
16: */
17:
18: #include <sys/queue.h>
19: #include <sys/types.h>
20: #include <sys/time.h>
21:
22: #include <stdarg.h>
23: #include <string.h>
24: #include <unistd.h>
25: #include <errno.h>
26:
27: #include "xmalloc.h"
28: #include "buffer.h"
29: #include "log.h"
30: #include "misc.h"
31: #include "key.h"
32: #include "authfd.h"
33: #include "ssh-pkcs11.h"
34:
35: /* borrows code from sftp-server and ssh-agent */
36:
37: struct pkcs11_keyinfo {
38: Key *key;
39: char *providername;
40: TAILQ_ENTRY(pkcs11_keyinfo) next;
41: };
42:
43: TAILQ_HEAD(, pkcs11_keyinfo) pkcs11_keylist;
44:
45: #define MAX_MSG_LENGTH 10240 /*XXX*/
46:
47: /* helper */
48: #define get_int() buffer_get_int(&iqueue);
49: #define get_string(lenp) buffer_get_string(&iqueue, lenp);
50:
51: /* input and output queue */
52: Buffer iqueue;
53: Buffer oqueue;
54:
55: static void
56: add_key(Key *k, char *name)
57: {
58: struct pkcs11_keyinfo *ki;
59:
60: ki = xcalloc(1, sizeof(*ki));
61: ki->providername = xstrdup(name);
62: ki->key = k;
63: TAILQ_INSERT_TAIL(&pkcs11_keylist, ki, next);
64: }
65:
66: static void
67: del_keys_by_name(char *name)
68: {
69: struct pkcs11_keyinfo *ki, *nxt;
70:
71: for (ki = TAILQ_FIRST(&pkcs11_keylist); ki; ki = nxt) {
72: nxt = TAILQ_NEXT(ki, next);
73: if (!strcmp(ki->providername, name)) {
74: TAILQ_REMOVE(&pkcs11_keylist, ki, next);
75: xfree(ki->providername);
76: key_free(ki->key);
77: free(ki);
78: }
79: }
80: }
81:
82: /* lookup matching 'private' key */
83: static Key *
84: lookup_key(Key *k)
85: {
86: struct pkcs11_keyinfo *ki;
87:
88: TAILQ_FOREACH(ki, &pkcs11_keylist, next) {
89: debug("check %p %s", ki, ki->providername);
90: if (key_equal(k, ki->key))
91: return (ki->key);
92: }
93: return (NULL);
94: }
95:
96: static void
97: send_msg(Buffer *m)
98: {
99: int mlen = buffer_len(m);
100:
101: buffer_put_int(&oqueue, mlen);
102: buffer_append(&oqueue, buffer_ptr(m), mlen);
103: buffer_consume(m, mlen);
104: }
105:
106: static void
107: process_add(void)
108: {
109: char *name, *pin;
110: Key **keys;
111: int i, nkeys;
112: u_char *blob;
113: u_int blen;
114: Buffer msg;
115:
116: buffer_init(&msg);
117: name = get_string(NULL);
118: pin = get_string(NULL);
119: if ((nkeys = pkcs11_add_provider(name, pin, &keys)) > 0) {
120: buffer_put_char(&msg, SSH2_AGENT_IDENTITIES_ANSWER);
121: buffer_put_int(&msg, nkeys);
122: for (i = 0; i < nkeys; i++) {
123: key_to_blob(keys[i], &blob, &blen);
124: buffer_put_string(&msg, blob, blen);
125: buffer_put_cstring(&msg, name);
126: xfree(blob);
127: add_key(keys[i], name);
128: }
129: xfree(keys);
130: } else {
131: buffer_put_char(&msg, SSH_AGENT_FAILURE);
132: }
133: xfree(pin);
134: xfree(name);
135: send_msg(&msg);
136: buffer_free(&msg);
137: }
138:
139: static void
140: process_del(void)
141: {
142: char *name, *pin;
143: Buffer msg;
144:
145: buffer_init(&msg);
146: name = get_string(NULL);
147: pin = get_string(NULL);
148: del_keys_by_name(name);
149: if (pkcs11_del_provider(name) == 0)
150: buffer_put_char(&msg, SSH_AGENT_SUCCESS);
151: else
152: buffer_put_char(&msg, SSH_AGENT_FAILURE);
153: xfree(pin);
154: xfree(name);
155: send_msg(&msg);
156: buffer_free(&msg);
157: }
158:
159: static void
160: process_sign(void)
161: {
162: u_char *blob, *data, *signature = NULL;
163: u_int blen, dlen, slen = 0;
1.4 dtucker 164: int ok = -1, ret;
1.1 markus 165: Key *key, *found;
166: Buffer msg;
167:
168: blob = get_string(&blen);
169: data = get_string(&dlen);
1.4 dtucker 170: (void)get_int(); /* XXX ignore flags */
1.1 markus 171:
172: if ((key = key_from_blob(blob, blen)) != NULL) {
173: if ((found = lookup_key(key)) != NULL) {
174: slen = RSA_size(key->rsa);
175: signature = xmalloc(slen);
176: if ((ret = RSA_private_encrypt(dlen, data, signature,
177: found->rsa, RSA_PKCS1_PADDING)) != -1) {
178: slen = ret;
179: ok = 0;
180: }
181: }
182: key_free(key);
183: }
184: buffer_init(&msg);
185: if (ok == 0) {
186: buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
187: buffer_put_string(&msg, signature, slen);
188: } else {
189: buffer_put_char(&msg, SSH_AGENT_FAILURE);
190: }
191: xfree(data);
192: xfree(blob);
193: if (signature != NULL)
194: xfree(signature);
195: send_msg(&msg);
196: buffer_free(&msg);
197: }
198:
199: static void
200: process(void)
201: {
202: u_int msg_len;
203: u_int buf_len;
204: u_int consumed;
205: u_int type;
206: u_char *cp;
207:
208: buf_len = buffer_len(&iqueue);
209: if (buf_len < 5)
210: return; /* Incomplete message. */
211: cp = buffer_ptr(&iqueue);
212: msg_len = get_u32(cp);
213: if (msg_len > MAX_MSG_LENGTH) {
214: error("bad message len %d", msg_len);
215: cleanup_exit(11);
216: }
217: if (buf_len < msg_len + 4)
218: return;
219: buffer_consume(&iqueue, 4);
220: buf_len -= 4;
221: type = buffer_get_char(&iqueue);
222: switch (type) {
223: case SSH_AGENTC_ADD_SMARTCARD_KEY:
224: debug("process_add");
225: process_add();
226: break;
227: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
228: debug("process_del");
229: process_del();
230: break;
231: case SSH2_AGENTC_SIGN_REQUEST:
232: debug("process_sign");
233: process_sign();
234: break;
235: default:
236: error("Unknown message %d", type);
237: break;
238: }
239: /* discard the remaining bytes from the current packet */
240: if (buf_len < buffer_len(&iqueue)) {
241: error("iqueue grew unexpectedly");
242: cleanup_exit(255);
243: }
244: consumed = buf_len - buffer_len(&iqueue);
245: if (msg_len < consumed) {
246: error("msg_len %d < consumed %d", msg_len, consumed);
247: cleanup_exit(255);
248: }
249: if (msg_len > consumed)
250: buffer_consume(&iqueue, msg_len - consumed);
251: }
252:
253: void
254: cleanup_exit(int i)
255: {
256: /* XXX */
257: _exit(i);
258: }
259:
260: int
261: main(int argc, char **argv)
262: {
263: fd_set *rset, *wset;
264: int in, out, max, log_stderr = 0;
265: ssize_t len, olen, set_size;
266: SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
267: LogLevel log_level = SYSLOG_LEVEL_ERROR;
268: char buf[4*4096];
1.2 deraadt 269: extern char *__progname;
1.1 markus 270:
271: TAILQ_INIT(&pkcs11_keylist);
272: pkcs11_init(0);
273:
274: log_init(__progname, log_level, log_facility, log_stderr);
275:
276: in = STDIN_FILENO;
277: out = STDOUT_FILENO;
278:
279: max = 0;
280: if (in > max)
281: max = in;
282: if (out > max)
283: max = out;
284:
285: buffer_init(&iqueue);
286: buffer_init(&oqueue);
287:
288: set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
289: rset = (fd_set *)xmalloc(set_size);
290: wset = (fd_set *)xmalloc(set_size);
291:
292: for (;;) {
293: memset(rset, 0, set_size);
294: memset(wset, 0, set_size);
295:
296: /*
297: * Ensure that we can read a full buffer and handle
298: * the worst-case length packet it can generate,
299: * otherwise apply backpressure by stopping reads.
300: */
301: if (buffer_check_alloc(&iqueue, sizeof(buf)) &&
302: buffer_check_alloc(&oqueue, MAX_MSG_LENGTH))
303: FD_SET(in, rset);
304:
305: olen = buffer_len(&oqueue);
306: if (olen > 0)
307: FD_SET(out, wset);
308:
309: if (select(max+1, rset, wset, NULL, NULL) < 0) {
310: if (errno == EINTR)
311: continue;
312: error("select: %s", strerror(errno));
313: cleanup_exit(2);
314: }
315:
316: /* copy stdin to iqueue */
317: if (FD_ISSET(in, rset)) {
318: len = read(in, buf, sizeof buf);
319: if (len == 0) {
320: debug("read eof");
321: cleanup_exit(0);
322: } else if (len < 0) {
323: error("read: %s", strerror(errno));
324: cleanup_exit(1);
325: } else {
326: buffer_append(&iqueue, buf, len);
327: }
328: }
329: /* send oqueue to stdout */
330: if (FD_ISSET(out, wset)) {
331: len = write(out, buffer_ptr(&oqueue), olen);
332: if (len < 0) {
333: error("write: %s", strerror(errno));
334: cleanup_exit(1);
335: } else {
336: buffer_consume(&oqueue, len);
337: }
338: }
339:
340: /*
341: * Process requests from client if we can fit the results
342: * into the output buffer, otherwise stop processing input
343: * and let the output queue drain.
344: */
345: if (buffer_check_alloc(&oqueue, MAX_MSG_LENGTH))
346: process();
347: }
348: }