1 /* $OpenBSD: ssh-pkcs11-client.c,v 1.19 2023/12/18 14:46:56 djm Exp $ */
2 /*
3 * Copyright (c) 2010 Markus Friedl. All rights reserved.
4 * Copyright (c) 2014 Pedro Martelletto. All rights reserved.
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <sys/types.h>
20 #include <sys/time.h>
21 #include <sys/socket.h>
22
23 #include <stdarg.h>
24 #include <string.h>
25 #include <unistd.h>
26 #include <errno.h>
27 #include <limits.h>
28
29 #include <openssl/ecdsa.h>
30 #include <openssl/rsa.h>
31
32 #include "pathnames.h"
33 #include "xmalloc.h"
34 #include "sshbuf.h"
35 #include "log.h"
36 #include "misc.h"
37 #include "sshkey.h"
38 #include "authfd.h"
39 #include "atomicio.h"
40 #include "ssh-pkcs11.h"
41 #include "ssherr.h"
42
43 /* borrows code from sftp-server and ssh-agent */
44
45 /*
46 * Maintain a list of ssh-pkcs11-helper subprocesses. These may be looked up
47 * by provider path or their unique EC/RSA METHOD pointers.
48 */
49 struct helper {
50 char *path;
51 pid_t pid;
52 int fd;
53 RSA_METHOD *rsa_meth;
54 EC_KEY_METHOD *ec_meth;
55 int (*rsa_finish)(RSA *rsa);
56 void (*ec_finish)(EC_KEY *key);
57 size_t nrsa, nec; /* number of active keys of each type */
58 };
59 static struct helper **helpers;
60 static size_t nhelpers;
61
62 static struct helper *
helper_by_provider(const char * path)63 helper_by_provider(const char *path)
64 {
65 size_t i;
66
67 for (i = 0; i < nhelpers; i++) {
68 if (helpers[i] == NULL || helpers[i]->path == NULL ||
69 helpers[i]->fd == -1)
70 continue;
71 if (strcmp(helpers[i]->path, path) == 0)
72 return helpers[i];
73 }
74 return NULL;
75 }
76
77 static struct helper *
helper_by_rsa(const RSA * rsa)78 helper_by_rsa(const RSA *rsa)
79 {
80 size_t i;
81 const RSA_METHOD *meth;
82
83 if ((meth = RSA_get_method(rsa)) == NULL)
84 return NULL;
85 for (i = 0; i < nhelpers; i++) {
86 if (helpers[i] != NULL && helpers[i]->rsa_meth == meth)
87 return helpers[i];
88 }
89 return NULL;
90
91 }
92
93 static struct helper *
helper_by_ec(const EC_KEY * ec)94 helper_by_ec(const EC_KEY *ec)
95 {
96 size_t i;
97 const EC_KEY_METHOD *meth;
98
99 if ((meth = EC_KEY_get_method(ec)) == NULL)
100 return NULL;
101 for (i = 0; i < nhelpers; i++) {
102 if (helpers[i] != NULL && helpers[i]->ec_meth == meth)
103 return helpers[i];
104 }
105 return NULL;
106
107 }
108
109 static void
helper_free(struct helper * helper)110 helper_free(struct helper *helper)
111 {
112 size_t i;
113 int found = 0;
114
115 if (helper == NULL)
116 return;
117 if (helper->path == NULL || helper->ec_meth == NULL ||
118 helper->rsa_meth == NULL)
119 fatal_f("inconsistent helper");
120 debug3_f("free helper for provider %s", helper->path);
121 for (i = 0; i < nhelpers; i++) {
122 if (helpers[i] == helper) {
123 if (found)
124 fatal_f("helper recorded more than once");
125 found = 1;
126 }
127 else if (found)
128 helpers[i - 1] = helpers[i];
129 }
130 if (found) {
131 helpers = xrecallocarray(helpers, nhelpers,
132 nhelpers - 1, sizeof(*helpers));
133 nhelpers--;
134 }
135 free(helper->path);
136 EC_KEY_METHOD_free(helper->ec_meth);
137 RSA_meth_free(helper->rsa_meth);
138 free(helper);
139 }
140
141 static void
helper_terminate(struct helper * helper)142 helper_terminate(struct helper *helper)
143 {
144 if (helper == NULL) {
145 return;
146 } else if (helper->fd == -1) {
147 debug3_f("already terminated");
148 } else {
149 debug3_f("terminating helper for %s; "
150 "remaining %zu RSA %zu ECDSA",
151 helper->path, helper->nrsa, helper->nec);
152 close(helper->fd);
153 /* XXX waitpid() */
154 helper->fd = -1;
155 helper->pid = -1;
156 }
157 /*
158 * Don't delete the helper entry until there are no remaining keys
159 * that reference it. Otherwise, any signing operation would call
160 * a free'd METHOD pointer and that would be bad.
161 */
162 if (helper->nrsa == 0 && helper->nec == 0)
163 helper_free(helper);
164 }
165
166 static void
send_msg(int fd,struct sshbuf * m)167 send_msg(int fd, struct sshbuf *m)
168 {
169 u_char buf[4];
170 size_t mlen = sshbuf_len(m);
171 int r;
172
173 if (fd == -1)
174 return;
175 POKE_U32(buf, mlen);
176 if (atomicio(vwrite, fd, buf, 4) != 4 ||
177 atomicio(vwrite, fd, sshbuf_mutable_ptr(m),
178 sshbuf_len(m)) != sshbuf_len(m))
179 error("write to helper failed");
180 if ((r = sshbuf_consume(m, mlen)) != 0)
181 fatal_fr(r, "consume");
182 }
183
184 static int
recv_msg(int fd,struct sshbuf * m)185 recv_msg(int fd, struct sshbuf *m)
186 {
187 u_int l, len;
188 u_char c, buf[1024];
189 int r;
190
191 sshbuf_reset(m);
192 if (fd == -1)
193 return 0; /* XXX */
194 if ((len = atomicio(read, fd, buf, 4)) != 4) {
195 error("read from helper failed: %u", len);
196 return (0); /* XXX */
197 }
198 len = PEEK_U32(buf);
199 if (len > 256 * 1024)
200 fatal("response too long: %u", len);
201 /* read len bytes into m */
202 while (len > 0) {
203 l = len;
204 if (l > sizeof(buf))
205 l = sizeof(buf);
206 if (atomicio(read, fd, buf, l) != l) {
207 error("response from helper failed.");
208 return (0); /* XXX */
209 }
210 if ((r = sshbuf_put(m, buf, l)) != 0)
211 fatal_fr(r, "sshbuf_put");
212 len -= l;
213 }
214 if ((r = sshbuf_get_u8(m, &c)) != 0)
215 fatal_fr(r, "parse type");
216 return c;
217 }
218
219 int
pkcs11_init(int interactive)220 pkcs11_init(int interactive)
221 {
222 return 0;
223 }
224
225 void
pkcs11_terminate(void)226 pkcs11_terminate(void)
227 {
228 size_t i;
229
230 debug3_f("terminating %zu helpers", nhelpers);
231 for (i = 0; i < nhelpers; i++)
232 helper_terminate(helpers[i]);
233 }
234
235 static int
rsa_encrypt(int flen,const u_char * from,u_char * to,RSA * rsa,int padding)236 rsa_encrypt(int flen, const u_char *from, u_char *to, RSA *rsa, int padding)
237 {
238 struct sshkey *key = NULL;
239 struct sshbuf *msg = NULL;
240 u_char *blob = NULL, *signature = NULL;
241 size_t blen, slen = 0;
242 int r, ret = -1;
243 struct helper *helper;
244
245 if ((helper = helper_by_rsa(rsa)) == NULL || helper->fd == -1)
246 fatal_f("no helper for PKCS11 key");
247 debug3_f("signing with PKCS11 provider %s", helper->path);
248 if (padding != RSA_PKCS1_PADDING)
249 goto fail;
250 key = sshkey_new(KEY_UNSPEC);
251 if (key == NULL) {
252 error_f("sshkey_new failed");
253 goto fail;
254 }
255 key->type = KEY_RSA;
256 RSA_up_ref(rsa);
257 key->rsa = rsa;
258 if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) {
259 error_fr(r, "encode key");
260 goto fail;
261 }
262 if ((msg = sshbuf_new()) == NULL)
263 fatal_f("sshbuf_new failed");
264 if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_SIGN_REQUEST)) != 0 ||
265 (r = sshbuf_put_string(msg, blob, blen)) != 0 ||
266 (r = sshbuf_put_string(msg, from, flen)) != 0 ||
267 (r = sshbuf_put_u32(msg, 0)) != 0)
268 fatal_fr(r, "compose");
269 send_msg(helper->fd, msg);
270 sshbuf_reset(msg);
271
272 if (recv_msg(helper->fd, msg) == SSH2_AGENT_SIGN_RESPONSE) {
273 if ((r = sshbuf_get_string(msg, &signature, &slen)) != 0)
274 fatal_fr(r, "parse");
275 if (slen <= (size_t)RSA_size(rsa)) {
276 memcpy(to, signature, slen);
277 ret = slen;
278 }
279 free(signature);
280 }
281 fail:
282 free(blob);
283 sshkey_free(key);
284 sshbuf_free(msg);
285 return (ret);
286 }
287
288 static int
rsa_finish(RSA * rsa)289 rsa_finish(RSA *rsa)
290 {
291 struct helper *helper;
292
293 if ((helper = helper_by_rsa(rsa)) == NULL)
294 fatal_f("no helper for PKCS11 key");
295 debug3_f("free PKCS11 RSA key for provider %s", helper->path);
296 if (helper->rsa_finish != NULL)
297 helper->rsa_finish(rsa);
298 if (helper->nrsa == 0)
299 fatal_f("RSA refcount error");
300 helper->nrsa--;
301 debug3_f("provider %s remaining keys: %zu RSA %zu ECDSA",
302 helper->path, helper->nrsa, helper->nec);
303 if (helper->nrsa == 0 && helper->nec == 0)
304 helper_terminate(helper);
305 return 1;
306 }
307
308 static ECDSA_SIG *
ecdsa_do_sign(const unsigned char * dgst,int dgst_len,const BIGNUM * inv,const BIGNUM * rp,EC_KEY * ec)309 ecdsa_do_sign(const unsigned char *dgst, int dgst_len, const BIGNUM *inv,
310 const BIGNUM *rp, EC_KEY *ec)
311 {
312 struct sshkey *key = NULL;
313 struct sshbuf *msg = NULL;
314 ECDSA_SIG *ret = NULL;
315 const u_char *cp;
316 u_char *blob = NULL, *signature = NULL;
317 size_t blen, slen = 0;
318 int r, nid;
319 struct helper *helper;
320
321 if ((helper = helper_by_ec(ec)) == NULL || helper->fd == -1)
322 fatal_f("no helper for PKCS11 key");
323 debug3_f("signing with PKCS11 provider %s", helper->path);
324 nid = sshkey_ecdsa_key_to_nid(ec);
325 if (nid < 0) {
326 error_f("couldn't get curve nid");
327 goto fail;
328 }
329
330 key = sshkey_new(KEY_UNSPEC);
331 if (key == NULL) {
332 error_f("sshkey_new failed");
333 goto fail;
334 }
335 key->ecdsa = ec;
336 key->ecdsa_nid = nid;
337 key->type = KEY_ECDSA;
338 EC_KEY_up_ref(ec);
339
340 if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) {
341 error_fr(r, "encode key");
342 goto fail;
343 }
344 if ((msg = sshbuf_new()) == NULL)
345 fatal_f("sshbuf_new failed");
346 if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_SIGN_REQUEST)) != 0 ||
347 (r = sshbuf_put_string(msg, blob, blen)) != 0 ||
348 (r = sshbuf_put_string(msg, dgst, dgst_len)) != 0 ||
349 (r = sshbuf_put_u32(msg, 0)) != 0)
350 fatal_fr(r, "compose");
351 send_msg(helper->fd, msg);
352 sshbuf_reset(msg);
353
354 if (recv_msg(helper->fd, msg) == SSH2_AGENT_SIGN_RESPONSE) {
355 if ((r = sshbuf_get_string(msg, &signature, &slen)) != 0)
356 fatal_fr(r, "parse");
357 cp = signature;
358 ret = d2i_ECDSA_SIG(NULL, &cp, slen);
359 free(signature);
360 }
361
362 fail:
363 free(blob);
364 sshkey_free(key);
365 sshbuf_free(msg);
366 return (ret);
367 }
368
369 static void
ecdsa_do_finish(EC_KEY * ec)370 ecdsa_do_finish(EC_KEY *ec)
371 {
372 struct helper *helper;
373
374 if ((helper = helper_by_ec(ec)) == NULL)
375 fatal_f("no helper for PKCS11 key");
376 debug3_f("free PKCS11 ECDSA key for provider %s", helper->path);
377 if (helper->ec_finish != NULL)
378 helper->ec_finish(ec);
379 if (helper->nec == 0)
380 fatal_f("ECDSA refcount error");
381 helper->nec--;
382 debug3_f("provider %s remaining keys: %zu RSA %zu ECDSA",
383 helper->path, helper->nrsa, helper->nec);
384 if (helper->nrsa == 0 && helper->nec == 0)
385 helper_terminate(helper);
386 }
387
388 /* redirect private key crypto operations to the ssh-pkcs11-helper */
389 static void
wrap_key(struct helper * helper,struct sshkey * k)390 wrap_key(struct helper *helper, struct sshkey *k)
391 {
392 debug3_f("wrap %s for provider %s", sshkey_type(k), helper->path);
393 if (k->type == KEY_RSA) {
394 RSA_set_method(k->rsa, helper->rsa_meth);
395 if (helper->nrsa++ >= INT_MAX)
396 fatal_f("RSA refcount error");
397 } else if (k->type == KEY_ECDSA) {
398 EC_KEY_set_method(k->ecdsa, helper->ec_meth);
399 if (helper->nec++ >= INT_MAX)
400 fatal_f("EC refcount error");
401 } else
402 fatal_f("unknown key type");
403 k->flags |= SSHKEY_FLAG_EXT;
404 debug3_f("provider %s remaining keys: %zu RSA %zu ECDSA",
405 helper->path, helper->nrsa, helper->nec);
406 }
407
408 /*
409 * Make a private PKCS#11-backed certificate by grafting a previously-loaded
410 * PKCS#11 private key and a public certificate key.
411 */
412 int
pkcs11_make_cert(const struct sshkey * priv,const struct sshkey * certpub,struct sshkey ** certprivp)413 pkcs11_make_cert(const struct sshkey *priv,
414 const struct sshkey *certpub, struct sshkey **certprivp)
415 {
416 struct helper *helper = NULL;
417 struct sshkey *ret;
418 int r;
419
420 debug3_f("private key type %s cert type %s", sshkey_type(priv),
421 sshkey_type(certpub));
422 *certprivp = NULL;
423 if (!sshkey_is_cert(certpub) || sshkey_is_cert(priv) ||
424 !sshkey_equal_public(priv, certpub)) {
425 error_f("private key %s doesn't match cert %s",
426 sshkey_type(priv), sshkey_type(certpub));
427 return SSH_ERR_INVALID_ARGUMENT;
428 }
429 *certprivp = NULL;
430 if (priv->type == KEY_RSA) {
431 if ((helper = helper_by_rsa(priv->rsa)) == NULL ||
432 helper->fd == -1)
433 fatal_f("no helper for PKCS11 RSA key");
434 if ((r = sshkey_from_private(priv, &ret)) != 0)
435 fatal_fr(r, "copy key");
436 RSA_set_method(ret->rsa, helper->rsa_meth);
437 if (helper->nrsa++ >= INT_MAX)
438 fatal_f("RSA refcount error");
439 } else if (priv->type == KEY_ECDSA) {
440 if ((helper = helper_by_ec(priv->ecdsa)) == NULL ||
441 helper->fd == -1)
442 fatal_f("no helper for PKCS11 EC key");
443 if ((r = sshkey_from_private(priv, &ret)) != 0)
444 fatal_fr(r, "copy key");
445 EC_KEY_set_method(ret->ecdsa, helper->ec_meth);
446 if (helper->nec++ >= INT_MAX)
447 fatal_f("EC refcount error");
448 } else
449 fatal_f("unknown key type %s", sshkey_type(priv));
450
451 ret->flags |= SSHKEY_FLAG_EXT;
452 if ((r = sshkey_to_certified(ret)) != 0 ||
453 (r = sshkey_cert_copy(certpub, ret)) != 0)
454 fatal_fr(r, "graft certificate");
455 debug3_f("provider %s remaining keys: %zu RSA %zu ECDSA",
456 helper->path, helper->nrsa, helper->nec);
457 /* success */
458 *certprivp = ret;
459 return 0;
460 }
461
462 static int
pkcs11_start_helper_methods(struct helper * helper)463 pkcs11_start_helper_methods(struct helper *helper)
464 {
465 int (*ec_init)(EC_KEY *key);
466 int (*ec_copy)(EC_KEY *dest, const EC_KEY *src);
467 int (*ec_set_group)(EC_KEY *key, const EC_GROUP *grp);
468 int (*ec_set_private)(EC_KEY *key, const BIGNUM *priv_key);
469 int (*ec_set_public)(EC_KEY *key, const EC_POINT *pub_key);
470 int (*ec_sign)(int, const unsigned char *, int, unsigned char *,
471 unsigned int *, const BIGNUM *, const BIGNUM *, EC_KEY *) = NULL;
472 RSA_METHOD *rsa_meth;
473 EC_KEY_METHOD *ec_meth;
474
475 if ((ec_meth = EC_KEY_METHOD_new(EC_KEY_OpenSSL())) == NULL)
476 return -1;
477 EC_KEY_METHOD_get_sign(ec_meth, &ec_sign, NULL, NULL);
478 EC_KEY_METHOD_set_sign(ec_meth, ec_sign, NULL, ecdsa_do_sign);
479 EC_KEY_METHOD_get_init(ec_meth, &ec_init, &helper->ec_finish,
480 &ec_copy, &ec_set_group, &ec_set_private, &ec_set_public);
481 EC_KEY_METHOD_set_init(ec_meth, ec_init, ecdsa_do_finish,
482 ec_copy, ec_set_group, ec_set_private, ec_set_public);
483
484 if ((rsa_meth = RSA_meth_dup(RSA_get_default_method())) == NULL)
485 fatal_f("RSA_meth_dup failed");
486 helper->rsa_finish = RSA_meth_get_finish(rsa_meth);
487 if (!RSA_meth_set1_name(rsa_meth, "ssh-pkcs11-helper") ||
488 !RSA_meth_set_priv_enc(rsa_meth, rsa_encrypt) ||
489 !RSA_meth_set_finish(rsa_meth, rsa_finish))
490 fatal_f("failed to prepare method");
491
492 helper->ec_meth = ec_meth;
493 helper->rsa_meth = rsa_meth;
494 return 0;
495 }
496
497 static struct helper *
pkcs11_start_helper(const char * path)498 pkcs11_start_helper(const char *path)
499 {
500 int pair[2];
501 char *prog, *verbosity = NULL;
502 struct helper *helper;
503 pid_t pid;
504
505 if (nhelpers >= INT_MAX)
506 fatal_f("too many helpers");
507 debug3_f("start helper for %s", path);
508 if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1) {
509 error_f("socketpair: %s", strerror(errno));
510 return NULL;
511 }
512 helper = xcalloc(1, sizeof(*helper));
513 if (pkcs11_start_helper_methods(helper) == -1) {
514 error_f("pkcs11_start_helper_methods failed");
515 goto fail;
516 }
517 if ((pid = fork()) == -1) {
518 error_f("fork: %s", strerror(errno));
519 fail:
520 close(pair[0]);
521 close(pair[1]);
522 RSA_meth_free(helper->rsa_meth);
523 EC_KEY_METHOD_free(helper->ec_meth);
524 free(helper);
525 return NULL;
526 } else if (pid == 0) {
527 if ((dup2(pair[1], STDIN_FILENO) == -1) ||
528 (dup2(pair[1], STDOUT_FILENO) == -1)) {
529 fprintf(stderr, "dup2: %s\n", strerror(errno));
530 _exit(1);
531 }
532 close(pair[0]);
533 close(pair[1]);
534 prog = getenv("SSH_PKCS11_HELPER");
535 if (prog == NULL || strlen(prog) == 0)
536 prog = _PATH_SSH_PKCS11_HELPER;
537 if (log_level_get() >= SYSLOG_LEVEL_DEBUG1)
538 verbosity = "-vvv";
539 debug_f("starting %s %s", prog,
540 verbosity == NULL ? "" : verbosity);
541 execlp(prog, prog, verbosity, (char *)NULL);
542 fprintf(stderr, "exec: %s: %s\n", prog, strerror(errno));
543 _exit(1);
544 }
545 close(pair[1]);
546 helper->fd = pair[0];
547 helper->path = xstrdup(path);
548 helper->pid = pid;
549 debug3_f("helper %zu for \"%s\" on fd %d pid %ld", nhelpers,
550 helper->path, helper->fd, (long)helper->pid);
551 helpers = xrecallocarray(helpers, nhelpers,
552 nhelpers + 1, sizeof(*helpers));
553 helpers[nhelpers++] = helper;
554 return helper;
555 }
556
557 int
pkcs11_add_provider(char * name,char * pin,struct sshkey *** keysp,char *** labelsp)558 pkcs11_add_provider(char *name, char *pin, struct sshkey ***keysp,
559 char ***labelsp)
560 {
561 struct sshkey *k;
562 int r, type;
563 u_char *blob;
564 char *label;
565 size_t blen;
566 u_int nkeys, i;
567 struct sshbuf *msg;
568 struct helper *helper;
569
570 if ((helper = helper_by_provider(name)) == NULL &&
571 (helper = pkcs11_start_helper(name)) == NULL)
572 return -1;
573
574 if ((msg = sshbuf_new()) == NULL)
575 fatal_f("sshbuf_new failed");
576 if ((r = sshbuf_put_u8(msg, SSH_AGENTC_ADD_SMARTCARD_KEY)) != 0 ||
577 (r = sshbuf_put_cstring(msg, name)) != 0 ||
578 (r = sshbuf_put_cstring(msg, pin)) != 0)
579 fatal_fr(r, "compose");
580 send_msg(helper->fd, msg);
581 sshbuf_reset(msg);
582
583 type = recv_msg(helper->fd, msg);
584 if (type == SSH2_AGENT_IDENTITIES_ANSWER) {
585 if ((r = sshbuf_get_u32(msg, &nkeys)) != 0)
586 fatal_fr(r, "parse nkeys");
587 *keysp = xcalloc(nkeys, sizeof(struct sshkey *));
588 if (labelsp)
589 *labelsp = xcalloc(nkeys, sizeof(char *));
590 for (i = 0; i < nkeys; i++) {
591 /* XXX clean up properly instead of fatal() */
592 if ((r = sshbuf_get_string(msg, &blob, &blen)) != 0 ||
593 (r = sshbuf_get_cstring(msg, &label, NULL)) != 0)
594 fatal_fr(r, "parse key");
595 if ((r = sshkey_from_blob(blob, blen, &k)) != 0)
596 fatal_fr(r, "decode key");
597 wrap_key(helper, k);
598 (*keysp)[i] = k;
599 if (labelsp)
600 (*labelsp)[i] = label;
601 else
602 free(label);
603 free(blob);
604 }
605 } else if (type == SSH2_AGENT_FAILURE) {
606 if ((r = sshbuf_get_u32(msg, &nkeys)) != 0)
607 nkeys = -1;
608 } else {
609 nkeys = -1;
610 }
611 sshbuf_free(msg);
612 return (nkeys);
613 }
614
615 int
pkcs11_del_provider(char * name)616 pkcs11_del_provider(char *name)
617 {
618 struct helper *helper;
619
620 /*
621 * ssh-agent deletes keys before calling this, so the helper entry
622 * should be gone before we get here.
623 */
624 debug3_f("delete %s", name);
625 if ((helper = helper_by_provider(name)) != NULL)
626 helper_terminate(helper);
627 return 0;
628 }
629