xref: /openbsd-src/usr.bin/ssh/ssh-pkcs11.c (revision 91f110e064cd7c194e59e019b83bb7496c1c84d4)
1 /* $OpenBSD: ssh-pkcs11.c,v 1.11 2013/11/13 13:48:20 markus Exp $ */
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/types.h>
19 #include <sys/queue.h>
20 #include <stdarg.h>
21 #include <stdio.h>
22 
23 #include <string.h>
24 #include <dlfcn.h>
25 
26 #include <openssl/x509.h>
27 
28 #define CRYPTOKI_COMPAT
29 #include "pkcs11.h"
30 
31 #include "log.h"
32 #include "misc.h"
33 #include "key.h"
34 #include "ssh-pkcs11.h"
35 #include "xmalloc.h"
36 
37 struct pkcs11_slotinfo {
38 	CK_TOKEN_INFO		token;
39 	CK_SESSION_HANDLE	session;
40 	int			logged_in;
41 };
42 
43 struct pkcs11_provider {
44 	char			*name;
45 	void			*handle;
46 	CK_FUNCTION_LIST	*function_list;
47 	CK_INFO			info;
48 	CK_ULONG		nslots;
49 	CK_SLOT_ID		*slotlist;
50 	struct pkcs11_slotinfo	*slotinfo;
51 	int			valid;
52 	int			refcount;
53 	TAILQ_ENTRY(pkcs11_provider) next;
54 };
55 
56 TAILQ_HEAD(, pkcs11_provider) pkcs11_providers;
57 
58 struct pkcs11_key {
59 	struct pkcs11_provider	*provider;
60 	CK_ULONG		slotidx;
61 	int			(*orig_finish)(RSA *rsa);
62 	RSA_METHOD		rsa_method;
63 	char			*keyid;
64 	int			keyid_len;
65 };
66 
67 int pkcs11_interactive = 0;
68 
69 int
70 pkcs11_init(int interactive)
71 {
72 	pkcs11_interactive = interactive;
73 	TAILQ_INIT(&pkcs11_providers);
74 	return (0);
75 }
76 
77 /*
78  * finalize a provider shared libarary, it's no longer usable.
79  * however, there might still be keys referencing this provider,
80  * so the actuall freeing of memory is handled by pkcs11_provider_unref().
81  * this is called when a provider gets unregistered.
82  */
83 static void
84 pkcs11_provider_finalize(struct pkcs11_provider *p)
85 {
86 	CK_RV rv;
87 	CK_ULONG i;
88 
89 	debug("pkcs11_provider_finalize: %p refcount %d valid %d",
90 	    p, p->refcount, p->valid);
91 	if (!p->valid)
92 		return;
93 	for (i = 0; i < p->nslots; i++) {
94 		if (p->slotinfo[i].session &&
95 		    (rv = p->function_list->C_CloseSession(
96 		    p->slotinfo[i].session)) != CKR_OK)
97 			error("C_CloseSession failed: %lu", rv);
98 	}
99 	if ((rv = p->function_list->C_Finalize(NULL)) != CKR_OK)
100 		error("C_Finalize failed: %lu", rv);
101 	p->valid = 0;
102 	p->function_list = NULL;
103 #ifdef HAVE_DLOPEN
104 	dlclose(p->handle);
105 #endif
106 }
107 
108 /*
109  * remove a reference to the provider.
110  * called when a key gets destroyed or when the provider is unregistered.
111  */
112 static void
113 pkcs11_provider_unref(struct pkcs11_provider *p)
114 {
115 	debug("pkcs11_provider_unref: %p refcount %d", p, p->refcount);
116 	if (--p->refcount <= 0) {
117 		if (p->valid)
118 			error("pkcs11_provider_unref: %p still valid", p);
119 		free(p->slotlist);
120 		free(p->slotinfo);
121 		free(p);
122 	}
123 }
124 
125 /* unregister all providers, keys might still point to the providers */
126 void
127 pkcs11_terminate(void)
128 {
129 	struct pkcs11_provider *p;
130 
131 	while ((p = TAILQ_FIRST(&pkcs11_providers)) != NULL) {
132 		TAILQ_REMOVE(&pkcs11_providers, p, next);
133 		pkcs11_provider_finalize(p);
134 		pkcs11_provider_unref(p);
135 	}
136 }
137 
138 /* lookup provider by name */
139 static struct pkcs11_provider *
140 pkcs11_provider_lookup(char *provider_id)
141 {
142 	struct pkcs11_provider *p;
143 
144 	TAILQ_FOREACH(p, &pkcs11_providers, next) {
145 		debug("check %p %s", p, p->name);
146 		if (!strcmp(provider_id, p->name))
147 			return (p);
148 	}
149 	return (NULL);
150 }
151 
152 /* unregister provider by name */
153 int
154 pkcs11_del_provider(char *provider_id)
155 {
156 	struct pkcs11_provider *p;
157 
158 	if ((p = pkcs11_provider_lookup(provider_id)) != NULL) {
159 		TAILQ_REMOVE(&pkcs11_providers, p, next);
160 		pkcs11_provider_finalize(p);
161 		pkcs11_provider_unref(p);
162 		return (0);
163 	}
164 	return (-1);
165 }
166 
167 /* openssl callback for freeing an RSA key */
168 static int
169 pkcs11_rsa_finish(RSA *rsa)
170 {
171 	struct pkcs11_key	*k11;
172 	int rv = -1;
173 
174 	if ((k11 = RSA_get_app_data(rsa)) != NULL) {
175 		if (k11->orig_finish)
176 			rv = k11->orig_finish(rsa);
177 		if (k11->provider)
178 			pkcs11_provider_unref(k11->provider);
179 		free(k11->keyid);
180 		free(k11);
181 	}
182 	return (rv);
183 }
184 
185 /* find a single 'obj' for given attributes */
186 static int
187 pkcs11_find(struct pkcs11_provider *p, CK_ULONG slotidx, CK_ATTRIBUTE *attr,
188     CK_ULONG nattr, CK_OBJECT_HANDLE *obj)
189 {
190 	CK_FUNCTION_LIST	*f;
191 	CK_SESSION_HANDLE	session;
192 	CK_ULONG		nfound = 0;
193 	CK_RV			rv;
194 	int			ret = -1;
195 
196 	f = p->function_list;
197 	session = p->slotinfo[slotidx].session;
198 	if ((rv = f->C_FindObjectsInit(session, attr, nattr)) != CKR_OK) {
199 		error("C_FindObjectsInit failed (nattr %lu): %lu", nattr, rv);
200 		return (-1);
201 	}
202 	if ((rv = f->C_FindObjects(session, obj, 1, &nfound)) != CKR_OK ||
203 	    nfound != 1) {
204 		debug("C_FindObjects failed (nfound %lu nattr %lu): %lu",
205 		    nfound, nattr, rv);
206 	} else
207 		ret = 0;
208 	if ((rv = f->C_FindObjectsFinal(session)) != CKR_OK)
209 		error("C_FindObjectsFinal failed: %lu", rv);
210 	return (ret);
211 }
212 
213 /* openssl callback doing the actual signing operation */
214 static int
215 pkcs11_rsa_private_encrypt(int flen, const u_char *from, u_char *to, RSA *rsa,
216     int padding)
217 {
218 	struct pkcs11_key	*k11;
219 	struct pkcs11_slotinfo	*si;
220 	CK_FUNCTION_LIST	*f;
221 	CK_OBJECT_HANDLE	obj;
222 	CK_ULONG		tlen = 0;
223 	CK_RV			rv;
224 	CK_OBJECT_CLASS		private_key_class = CKO_PRIVATE_KEY;
225 	CK_BBOOL		true_val = CK_TRUE;
226 	CK_MECHANISM		mech = {
227 		CKM_RSA_PKCS, NULL_PTR, 0
228 	};
229 	CK_ATTRIBUTE		key_filter[] = {
230 		{CKA_CLASS, &private_key_class, sizeof(private_key_class) },
231 		{CKA_ID, NULL, 0},
232 		{CKA_SIGN, &true_val, sizeof(true_val) }
233 	};
234 	char			*pin, prompt[1024];
235 	int			rval = -1;
236 
237 	if ((k11 = RSA_get_app_data(rsa)) == NULL) {
238 		error("RSA_get_app_data failed for rsa %p", rsa);
239 		return (-1);
240 	}
241 	if (!k11->provider || !k11->provider->valid) {
242 		error("no pkcs11 (valid) provider for rsa %p", rsa);
243 		return (-1);
244 	}
245 	f = k11->provider->function_list;
246 	si = &k11->provider->slotinfo[k11->slotidx];
247 	if ((si->token.flags & CKF_LOGIN_REQUIRED) && !si->logged_in) {
248 		if (!pkcs11_interactive) {
249 			error("need pin");
250 			return (-1);
251 		}
252 		snprintf(prompt, sizeof(prompt), "Enter PIN for '%s': ",
253 		    si->token.label);
254 		pin = read_passphrase(prompt, RP_ALLOW_EOF);
255 		if (pin == NULL)
256 			return (-1);	/* bail out */
257 		if ((rv = f->C_Login(si->session, CKU_USER,
258 		    (u_char *)pin, strlen(pin))) != CKR_OK) {
259 			free(pin);
260 			error("C_Login failed: %lu", rv);
261 			return (-1);
262 		}
263 		free(pin);
264 		si->logged_in = 1;
265 	}
266 	key_filter[1].pValue = k11->keyid;
267 	key_filter[1].ulValueLen = k11->keyid_len;
268 	/* try to find object w/CKA_SIGN first, retry w/o */
269 	if (pkcs11_find(k11->provider, k11->slotidx, key_filter, 3, &obj) < 0 &&
270 	    pkcs11_find(k11->provider, k11->slotidx, key_filter, 2, &obj) < 0) {
271 		error("cannot find private key");
272 	} else if ((rv = f->C_SignInit(si->session, &mech, obj)) != CKR_OK) {
273 		error("C_SignInit failed: %lu", rv);
274 	} else {
275 		/* XXX handle CKR_BUFFER_TOO_SMALL */
276 		tlen = RSA_size(rsa);
277 		rv = f->C_Sign(si->session, (CK_BYTE *)from, flen, to, &tlen);
278 		if (rv == CKR_OK)
279 			rval = tlen;
280 		else
281 			error("C_Sign failed: %lu", rv);
282 	}
283 	return (rval);
284 }
285 
286 static int
287 pkcs11_rsa_private_decrypt(int flen, const u_char *from, u_char *to, RSA *rsa,
288     int padding)
289 {
290 	return (-1);
291 }
292 
293 /* redirect private key operations for rsa key to pkcs11 token */
294 static int
295 pkcs11_rsa_wrap(struct pkcs11_provider *provider, CK_ULONG slotidx,
296     CK_ATTRIBUTE *keyid_attrib, RSA *rsa)
297 {
298 	struct pkcs11_key	*k11;
299 	const RSA_METHOD	*def = RSA_get_default_method();
300 
301 	k11 = xcalloc(1, sizeof(*k11));
302 	k11->provider = provider;
303 	provider->refcount++;	/* provider referenced by RSA key */
304 	k11->slotidx = slotidx;
305 	/* identify key object on smartcard */
306 	k11->keyid_len = keyid_attrib->ulValueLen;
307 	k11->keyid = xmalloc(k11->keyid_len);
308 	memcpy(k11->keyid, keyid_attrib->pValue, k11->keyid_len);
309 	k11->orig_finish = def->finish;
310 	memcpy(&k11->rsa_method, def, sizeof(k11->rsa_method));
311 	k11->rsa_method.name = "pkcs11";
312 	k11->rsa_method.rsa_priv_enc = pkcs11_rsa_private_encrypt;
313 	k11->rsa_method.rsa_priv_dec = pkcs11_rsa_private_decrypt;
314 	k11->rsa_method.finish = pkcs11_rsa_finish;
315 	RSA_set_method(rsa, &k11->rsa_method);
316 	RSA_set_app_data(rsa, k11);
317 	return (0);
318 }
319 
320 /* remove trailing spaces */
321 static void
322 rmspace(u_char *buf, size_t len)
323 {
324 	size_t i;
325 
326 	if (!len)
327 		return;
328 	for (i = len - 1;  i > 0; i--)
329 		if (i == len - 1 || buf[i] == ' ')
330 			buf[i] = '\0';
331 		else
332 			break;
333 }
334 
335 /*
336  * open a pkcs11 session and login if required.
337  * if pin == NULL we delay login until key use
338  */
339 static int
340 pkcs11_open_session(struct pkcs11_provider *p, CK_ULONG slotidx, char *pin)
341 {
342 	CK_RV			rv;
343 	CK_FUNCTION_LIST	*f;
344 	CK_SESSION_HANDLE	session;
345 	int			login_required;
346 
347 	f = p->function_list;
348 	login_required = p->slotinfo[slotidx].token.flags & CKF_LOGIN_REQUIRED;
349 	if (pin && login_required && !strlen(pin)) {
350 		error("pin required");
351 		return (-1);
352 	}
353 	if ((rv = f->C_OpenSession(p->slotlist[slotidx], CKF_RW_SESSION|
354 	    CKF_SERIAL_SESSION, NULL, NULL, &session))
355 	    != CKR_OK) {
356 		error("C_OpenSession failed: %lu", rv);
357 		return (-1);
358 	}
359 	if (login_required && pin) {
360 		if ((rv = f->C_Login(session, CKU_USER,
361 		    (u_char *)pin, strlen(pin))) != CKR_OK) {
362 			error("C_Login failed: %lu", rv);
363 			if ((rv = f->C_CloseSession(session)) != CKR_OK)
364 				error("C_CloseSession failed: %lu", rv);
365 			return (-1);
366 		}
367 		p->slotinfo[slotidx].logged_in = 1;
368 	}
369 	p->slotinfo[slotidx].session = session;
370 	return (0);
371 }
372 
373 /*
374  * lookup public keys for token in slot identified by slotidx,
375  * add 'wrapped' public keys to the 'keysp' array and increment nkeys.
376  * keysp points to an (possibly empty) array with *nkeys keys.
377  */
378 static int pkcs11_fetch_keys_filter(struct pkcs11_provider *, CK_ULONG,
379     CK_ATTRIBUTE [], CK_ATTRIBUTE [3], Key ***, int *)
380 	__attribute__((__bounded__(__minbytes__,4, 3 * sizeof(CK_ATTRIBUTE))));
381 
382 static int
383 pkcs11_fetch_keys(struct pkcs11_provider *p, CK_ULONG slotidx,
384     Key ***keysp, int *nkeys)
385 {
386 	CK_OBJECT_CLASS		pubkey_class = CKO_PUBLIC_KEY;
387 	CK_OBJECT_CLASS		cert_class = CKO_CERTIFICATE;
388 	CK_ATTRIBUTE		pubkey_filter[] = {
389 		{ CKA_CLASS, &pubkey_class, sizeof(pubkey_class) }
390 	};
391 	CK_ATTRIBUTE		cert_filter[] = {
392 		{ CKA_CLASS, &cert_class, sizeof(cert_class) }
393 	};
394 	CK_ATTRIBUTE		pubkey_attribs[] = {
395 		{ CKA_ID, NULL, 0 },
396 		{ CKA_MODULUS, NULL, 0 },
397 		{ CKA_PUBLIC_EXPONENT, NULL, 0 }
398 	};
399 	CK_ATTRIBUTE		cert_attribs[] = {
400 		{ CKA_ID, NULL, 0 },
401 		{ CKA_SUBJECT, NULL, 0 },
402 		{ CKA_VALUE, NULL, 0 }
403 	};
404 
405 	if (pkcs11_fetch_keys_filter(p, slotidx, pubkey_filter, pubkey_attribs,
406 	    keysp, nkeys) < 0 ||
407 	    pkcs11_fetch_keys_filter(p, slotidx, cert_filter, cert_attribs,
408 	    keysp, nkeys) < 0)
409 		return (-1);
410 	return (0);
411 }
412 
413 static int
414 pkcs11_key_included(Key ***keysp, int *nkeys, Key *key)
415 {
416 	int i;
417 
418 	for (i = 0; i < *nkeys; i++)
419 		if (key_equal(key, (*keysp)[i]))
420 			return (1);
421 	return (0);
422 }
423 
424 static int
425 pkcs11_fetch_keys_filter(struct pkcs11_provider *p, CK_ULONG slotidx,
426     CK_ATTRIBUTE filter[], CK_ATTRIBUTE attribs[3],
427     Key ***keysp, int *nkeys)
428 {
429 	Key			*key;
430 	RSA			*rsa;
431 	X509 			*x509;
432 	EVP_PKEY		*evp;
433 	int			i;
434 	const u_char		*cp;
435 	CK_RV			rv;
436 	CK_OBJECT_HANDLE	obj;
437 	CK_ULONG		nfound;
438 	CK_SESSION_HANDLE	session;
439 	CK_FUNCTION_LIST	*f;
440 
441 	f = p->function_list;
442 	session = p->slotinfo[slotidx].session;
443 	/* setup a filter the looks for public keys */
444 	if ((rv = f->C_FindObjectsInit(session, filter, 1)) != CKR_OK) {
445 		error("C_FindObjectsInit failed: %lu", rv);
446 		return (-1);
447 	}
448 	while (1) {
449 		/* XXX 3 attributes in attribs[] */
450 		for (i = 0; i < 3; i++) {
451 			attribs[i].pValue = NULL;
452 			attribs[i].ulValueLen = 0;
453 		}
454 		if ((rv = f->C_FindObjects(session, &obj, 1, &nfound)) != CKR_OK
455 		    || nfound == 0)
456 			break;
457 		/* found a key, so figure out size of the attributes */
458 		if ((rv = f->C_GetAttributeValue(session, obj, attribs, 3))
459 		    != CKR_OK) {
460 			error("C_GetAttributeValue failed: %lu", rv);
461 			continue;
462 		}
463 		/* check that none of the attributes are zero length */
464 		if (attribs[0].ulValueLen == 0 ||
465 		    attribs[1].ulValueLen == 0 ||
466 		    attribs[2].ulValueLen == 0) {
467 			continue;
468 		}
469 		/* allocate buffers for attributes */
470 		for (i = 0; i < 3; i++)
471 			attribs[i].pValue = xmalloc(attribs[i].ulValueLen);
472 		/*
473 		 * retrieve ID, modulus and public exponent of RSA key,
474 		 * or ID, subject and value for certificates.
475 		 */
476 		rsa = NULL;
477 		if ((rv = f->C_GetAttributeValue(session, obj, attribs, 3))
478 		    != CKR_OK) {
479 			error("C_GetAttributeValue failed: %lu", rv);
480 		} else if (attribs[1].type == CKA_MODULUS ) {
481 			if ((rsa = RSA_new()) == NULL) {
482 				error("RSA_new failed");
483 			} else {
484 				rsa->n = BN_bin2bn(attribs[1].pValue,
485 				    attribs[1].ulValueLen, NULL);
486 				rsa->e = BN_bin2bn(attribs[2].pValue,
487 				    attribs[2].ulValueLen, NULL);
488 			}
489 		} else {
490 			cp = attribs[2].pValue;
491 			if ((x509 = X509_new()) == NULL) {
492 				error("X509_new failed");
493 			} else if (d2i_X509(&x509, &cp, attribs[2].ulValueLen)
494 			    == NULL) {
495 				error("d2i_X509 failed");
496 			} else if ((evp = X509_get_pubkey(x509)) == NULL ||
497 			    evp->type != EVP_PKEY_RSA ||
498 			    evp->pkey.rsa == NULL) {
499 				debug("X509_get_pubkey failed or no rsa");
500 			} else if ((rsa = RSAPublicKey_dup(evp->pkey.rsa))
501 			    == NULL) {
502 				error("RSAPublicKey_dup");
503 			}
504 			if (x509)
505 				X509_free(x509);
506 		}
507 		if (rsa && rsa->n && rsa->e &&
508 		    pkcs11_rsa_wrap(p, slotidx, &attribs[0], rsa) == 0) {
509 			key = key_new(KEY_UNSPEC);
510 			key->rsa = rsa;
511 			key->type = KEY_RSA;
512 			key->flags |= KEY_FLAG_EXT;
513 			if (pkcs11_key_included(keysp, nkeys, key)) {
514 				key_free(key);
515 			} else {
516 				/* expand key array and add key */
517 				*keysp = xrealloc(*keysp, *nkeys + 1,
518 				    sizeof(Key *));
519 				(*keysp)[*nkeys] = key;
520 				*nkeys = *nkeys + 1;
521 				debug("have %d keys", *nkeys);
522 			}
523 		} else if (rsa) {
524 			RSA_free(rsa);
525 		}
526 		for (i = 0; i < 3; i++)
527 			free(attribs[i].pValue);
528 	}
529 	if ((rv = f->C_FindObjectsFinal(session)) != CKR_OK)
530 		error("C_FindObjectsFinal failed: %lu", rv);
531 	return (0);
532 }
533 
534 #ifdef HAVE_DLOPEN
535 /* register a new provider, fails if provider already exists */
536 int
537 pkcs11_add_provider(char *provider_id, char *pin, Key ***keyp)
538 {
539 	int nkeys, need_finalize = 0;
540 	struct pkcs11_provider *p = NULL;
541 	void *handle = NULL;
542 	CK_RV (*getfunctionlist)(CK_FUNCTION_LIST **);
543 	CK_RV rv;
544 	CK_FUNCTION_LIST *f = NULL;
545 	CK_TOKEN_INFO *token;
546 	CK_ULONG i;
547 
548 	*keyp = NULL;
549 	if (pkcs11_provider_lookup(provider_id) != NULL) {
550 		error("provider already registered: %s", provider_id);
551 		goto fail;
552 	}
553 	/* open shared pkcs11-libarary */
554 	if ((handle = dlopen(provider_id, RTLD_NOW)) == NULL) {
555 		error("dlopen %s failed: %s", provider_id, dlerror());
556 		goto fail;
557 	}
558 	if ((getfunctionlist = dlsym(handle, "C_GetFunctionList")) == NULL) {
559 		error("dlsym(C_GetFunctionList) failed: %s", dlerror());
560 		goto fail;
561 	}
562 	p = xcalloc(1, sizeof(*p));
563 	p->name = xstrdup(provider_id);
564 	p->handle = handle;
565 	/* setup the pkcs11 callbacks */
566 	if ((rv = (*getfunctionlist)(&f)) != CKR_OK) {
567 		error("C_GetFunctionList failed: %lu", rv);
568 		goto fail;
569 	}
570 	p->function_list = f;
571 	if ((rv = f->C_Initialize(NULL)) != CKR_OK) {
572 		error("C_Initialize failed: %lu", rv);
573 		goto fail;
574 	}
575 	need_finalize = 1;
576 	if ((rv = f->C_GetInfo(&p->info)) != CKR_OK) {
577 		error("C_GetInfo failed: %lu", rv);
578 		goto fail;
579 	}
580 	rmspace(p->info.manufacturerID, sizeof(p->info.manufacturerID));
581 	rmspace(p->info.libraryDescription, sizeof(p->info.libraryDescription));
582 	debug("manufacturerID <%s> cryptokiVersion %d.%d"
583 	    " libraryDescription <%s> libraryVersion %d.%d",
584 	    p->info.manufacturerID,
585 	    p->info.cryptokiVersion.major,
586 	    p->info.cryptokiVersion.minor,
587 	    p->info.libraryDescription,
588 	    p->info.libraryVersion.major,
589 	    p->info.libraryVersion.minor);
590 	if ((rv = f->C_GetSlotList(CK_TRUE, NULL, &p->nslots)) != CKR_OK) {
591 		error("C_GetSlotList failed: %lu", rv);
592 		goto fail;
593 	}
594 	if (p->nslots == 0) {
595 		error("no slots");
596 		goto fail;
597 	}
598 	p->slotlist = xcalloc(p->nslots, sizeof(CK_SLOT_ID));
599 	if ((rv = f->C_GetSlotList(CK_TRUE, p->slotlist, &p->nslots))
600 	    != CKR_OK) {
601 		error("C_GetSlotList failed: %lu", rv);
602 		goto fail;
603 	}
604 	p->slotinfo = xcalloc(p->nslots, sizeof(struct pkcs11_slotinfo));
605 	p->valid = 1;
606 	nkeys = 0;
607 	for (i = 0; i < p->nslots; i++) {
608 		token = &p->slotinfo[i].token;
609 		if ((rv = f->C_GetTokenInfo(p->slotlist[i], token))
610 		    != CKR_OK) {
611 			error("C_GetTokenInfo failed: %lu", rv);
612 			continue;
613 		}
614 		rmspace(token->label, sizeof(token->label));
615 		rmspace(token->manufacturerID, sizeof(token->manufacturerID));
616 		rmspace(token->model, sizeof(token->model));
617 		rmspace(token->serialNumber, sizeof(token->serialNumber));
618 		debug("label <%s> manufacturerID <%s> model <%s> serial <%s>"
619 		    " flags 0x%lx",
620 		    token->label, token->manufacturerID, token->model,
621 		    token->serialNumber, token->flags);
622 		/* open session, login with pin and retrieve public keys */
623 		if (pkcs11_open_session(p, i, pin) == 0)
624 			pkcs11_fetch_keys(p, i, keyp, &nkeys);
625 	}
626 	if (nkeys > 0) {
627 		TAILQ_INSERT_TAIL(&pkcs11_providers, p, next);
628 		p->refcount++;	/* add to provider list */
629 		return (nkeys);
630 	}
631 	error("no keys");
632 	/* don't add the provider, since it does not have any keys */
633 fail:
634 	if (need_finalize && (rv = f->C_Finalize(NULL)) != CKR_OK)
635 		error("C_Finalize failed: %lu", rv);
636 	if (p) {
637 		free(p->slotlist);
638 		free(p->slotinfo);
639 		free(p);
640 	}
641 	if (handle)
642 		dlclose(handle);
643 	return (-1);
644 }
645 #else
646 int
647 pkcs11_add_provider(char *provider_id, char *pin, Key ***keyp)
648 {
649 	error("dlopen() not supported");
650 	return (-1);
651 }
652 #endif
653