xref: /netbsd-src/crypto/external/bsd/openssl/dist/ssl/ssl_cert.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*
2  * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the OpenSSL license (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 /* ====================================================================
11  * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
12  * ECC cipher suite support in OpenSSL originally developed by
13  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
14  */
15 
16 #include <stdio.h>
17 #include <sys/types.h>
18 
19 #include "e_os.h"
20 #include "internal/o_dir.h"
21 #include <openssl/lhash.h>
22 #include <openssl/bio.h>
23 #include <openssl/pem.h>
24 #include <openssl/x509v3.h>
25 #include <openssl/dh.h>
26 #include <openssl/bn.h>
27 #include <openssl/crypto.h>
28 #include "ssl_locl.h"
29 #include "internal/thread_once.h"
30 
31 static int ssl_security_default_callback(const SSL *s, const SSL_CTX *ctx,
32                                          int op, int bits, int nid, void *other,
33                                          void *ex);
34 
35 static CRYPTO_ONCE ssl_x509_store_ctx_once = CRYPTO_ONCE_STATIC_INIT;
36 static volatile int ssl_x509_store_ctx_idx = -1;
37 
38 DEFINE_RUN_ONCE_STATIC(ssl_x509_store_ctx_init)
39 {
40     ssl_x509_store_ctx_idx = X509_STORE_CTX_get_ex_new_index(0,
41                                                              "SSL for verify callback",
42                                                              NULL, NULL, NULL);
43     return ssl_x509_store_ctx_idx >= 0;
44 }
45 
46 int SSL_get_ex_data_X509_STORE_CTX_idx(void)
47 {
48 
49     if (!RUN_ONCE(&ssl_x509_store_ctx_once, ssl_x509_store_ctx_init))
50         return -1;
51     return ssl_x509_store_ctx_idx;
52 }
53 
54 CERT *ssl_cert_new(void)
55 {
56     CERT *ret = OPENSSL_zalloc(sizeof(*ret));
57 
58     if (ret == NULL) {
59         SSLerr(SSL_F_SSL_CERT_NEW, ERR_R_MALLOC_FAILURE);
60         return NULL;
61     }
62 
63     ret->key = &(ret->pkeys[SSL_PKEY_RSA_ENC]);
64     ret->references = 1;
65     ret->sec_cb = ssl_security_default_callback;
66     ret->sec_level = OPENSSL_TLS_SECURITY_LEVEL;
67     ret->sec_ex = NULL;
68     ret->lock = CRYPTO_THREAD_lock_new();
69     if (ret->lock == NULL) {
70         SSLerr(SSL_F_SSL_CERT_NEW, ERR_R_MALLOC_FAILURE);
71         OPENSSL_free(ret);
72         return NULL;
73     }
74 
75     return ret;
76 }
77 
78 CERT *ssl_cert_dup(CERT *cert)
79 {
80     CERT *ret = OPENSSL_zalloc(sizeof(*ret));
81     int i;
82 
83     if (ret == NULL) {
84         SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
85         return NULL;
86     }
87 
88     ret->references = 1;
89     ret->key = &ret->pkeys[cert->key - cert->pkeys];
90     ret->lock = CRYPTO_THREAD_lock_new();
91     if (ret->lock == NULL) {
92         SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
93         OPENSSL_free(ret);
94         return NULL;
95     }
96 #ifndef OPENSSL_NO_DH
97     if (cert->dh_tmp != NULL) {
98         ret->dh_tmp = cert->dh_tmp;
99         EVP_PKEY_up_ref(ret->dh_tmp);
100     }
101     ret->dh_tmp_cb = cert->dh_tmp_cb;
102     ret->dh_tmp_auto = cert->dh_tmp_auto;
103 #endif
104 
105     for (i = 0; i < SSL_PKEY_NUM; i++) {
106         CERT_PKEY *cpk = cert->pkeys + i;
107         CERT_PKEY *rpk = ret->pkeys + i;
108         if (cpk->x509 != NULL) {
109             rpk->x509 = cpk->x509;
110             X509_up_ref(rpk->x509);
111         }
112 
113         if (cpk->privatekey != NULL) {
114             rpk->privatekey = cpk->privatekey;
115             EVP_PKEY_up_ref(cpk->privatekey);
116         }
117 
118         if (cpk->chain) {
119             rpk->chain = X509_chain_up_ref(cpk->chain);
120             if (!rpk->chain) {
121                 SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
122                 goto err;
123             }
124         }
125         if (cert->pkeys[i].serverinfo != NULL) {
126             /* Just copy everything. */
127             ret->pkeys[i].serverinfo =
128                 OPENSSL_malloc(cert->pkeys[i].serverinfo_length);
129             if (ret->pkeys[i].serverinfo == NULL) {
130                 SSLerr(SSL_F_SSL_CERT_DUP, ERR_R_MALLOC_FAILURE);
131                 goto err;
132             }
133             ret->pkeys[i].serverinfo_length = cert->pkeys[i].serverinfo_length;
134             memcpy(ret->pkeys[i].serverinfo,
135                    cert->pkeys[i].serverinfo, cert->pkeys[i].serverinfo_length);
136         }
137     }
138 
139     /* Configured sigalgs copied across */
140     if (cert->conf_sigalgs) {
141         ret->conf_sigalgs = OPENSSL_malloc(cert->conf_sigalgslen);
142         if (ret->conf_sigalgs == NULL)
143             goto err;
144         memcpy(ret->conf_sigalgs, cert->conf_sigalgs, cert->conf_sigalgslen);
145         ret->conf_sigalgslen = cert->conf_sigalgslen;
146     } else
147         ret->conf_sigalgs = NULL;
148 
149     if (cert->client_sigalgs) {
150         ret->client_sigalgs = OPENSSL_malloc(cert->client_sigalgslen);
151         if (ret->client_sigalgs == NULL)
152             goto err;
153         memcpy(ret->client_sigalgs, cert->client_sigalgs,
154                cert->client_sigalgslen);
155         ret->client_sigalgslen = cert->client_sigalgslen;
156     } else
157         ret->client_sigalgs = NULL;
158     /* Shared sigalgs also NULL */
159     ret->shared_sigalgs = NULL;
160     /* Copy any custom client certificate types */
161     if (cert->ctypes) {
162         ret->ctypes = OPENSSL_malloc(cert->ctype_num);
163         if (ret->ctypes == NULL)
164             goto err;
165         memcpy(ret->ctypes, cert->ctypes, cert->ctype_num);
166         ret->ctype_num = cert->ctype_num;
167     }
168 
169     ret->cert_flags = cert->cert_flags;
170 
171     ret->cert_cb = cert->cert_cb;
172     ret->cert_cb_arg = cert->cert_cb_arg;
173 
174     if (cert->verify_store) {
175         X509_STORE_up_ref(cert->verify_store);
176         ret->verify_store = cert->verify_store;
177     }
178 
179     if (cert->chain_store) {
180         X509_STORE_up_ref(cert->chain_store);
181         ret->chain_store = cert->chain_store;
182     }
183 
184     ret->sec_cb = cert->sec_cb;
185     ret->sec_level = cert->sec_level;
186     ret->sec_ex = cert->sec_ex;
187 
188     if (!custom_exts_copy(&ret->cli_ext, &cert->cli_ext))
189         goto err;
190     if (!custom_exts_copy(&ret->srv_ext, &cert->srv_ext))
191         goto err;
192 #ifndef OPENSSL_NO_PSK
193     if (cert->psk_identity_hint) {
194         ret->psk_identity_hint = OPENSSL_strdup(cert->psk_identity_hint);
195         if (ret->psk_identity_hint == NULL)
196             goto err;
197     }
198 #endif
199     return ret;
200 
201  err:
202     ssl_cert_free(ret);
203 
204     return NULL;
205 }
206 
207 /* Free up and clear all certificates and chains */
208 
209 void ssl_cert_clear_certs(CERT *c)
210 {
211     int i;
212     if (c == NULL)
213         return;
214     for (i = 0; i < SSL_PKEY_NUM; i++) {
215         CERT_PKEY *cpk = c->pkeys + i;
216         X509_free(cpk->x509);
217         cpk->x509 = NULL;
218         EVP_PKEY_free(cpk->privatekey);
219         cpk->privatekey = NULL;
220         sk_X509_pop_free(cpk->chain, X509_free);
221         cpk->chain = NULL;
222         OPENSSL_free(cpk->serverinfo);
223         cpk->serverinfo = NULL;
224         cpk->serverinfo_length = 0;
225     }
226 }
227 
228 void ssl_cert_free(CERT *c)
229 {
230     int i;
231 
232     if (c == NULL)
233         return;
234 
235     CRYPTO_atomic_add(&c->references, -1, &i, c->lock);
236     REF_PRINT_COUNT("CERT", c);
237     if (i > 0)
238         return;
239     REF_ASSERT_ISNT(i < 0);
240 
241 #ifndef OPENSSL_NO_DH
242     EVP_PKEY_free(c->dh_tmp);
243 #endif
244 
245     ssl_cert_clear_certs(c);
246     OPENSSL_free(c->conf_sigalgs);
247     OPENSSL_free(c->client_sigalgs);
248     OPENSSL_free(c->shared_sigalgs);
249     OPENSSL_free(c->ctypes);
250     X509_STORE_free(c->verify_store);
251     X509_STORE_free(c->chain_store);
252     custom_exts_free(&c->cli_ext);
253     custom_exts_free(&c->srv_ext);
254 #ifndef OPENSSL_NO_PSK
255     OPENSSL_free(c->psk_identity_hint);
256 #endif
257     CRYPTO_THREAD_lock_free(c->lock);
258     OPENSSL_free(c);
259 }
260 
261 int ssl_cert_set0_chain(SSL *s, SSL_CTX *ctx, STACK_OF(X509) *chain)
262 {
263     int i, r;
264     CERT_PKEY *cpk = s ? s->cert->key : ctx->cert->key;
265     if (!cpk)
266         return 0;
267     for (i = 0; i < sk_X509_num(chain); i++) {
268         r = ssl_security_cert(s, ctx, sk_X509_value(chain, i), 0, 0);
269         if (r != 1) {
270             SSLerr(SSL_F_SSL_CERT_SET0_CHAIN, r);
271             return 0;
272         }
273     }
274     sk_X509_pop_free(cpk->chain, X509_free);
275     cpk->chain = chain;
276     return 1;
277 }
278 
279 int ssl_cert_set1_chain(SSL *s, SSL_CTX *ctx, STACK_OF(X509) *chain)
280 {
281     STACK_OF(X509) *dchain;
282     if (!chain)
283         return ssl_cert_set0_chain(s, ctx, NULL);
284     dchain = X509_chain_up_ref(chain);
285     if (!dchain)
286         return 0;
287     if (!ssl_cert_set0_chain(s, ctx, dchain)) {
288         sk_X509_pop_free(dchain, X509_free);
289         return 0;
290     }
291     return 1;
292 }
293 
294 int ssl_cert_add0_chain_cert(SSL *s, SSL_CTX *ctx, X509 *x)
295 {
296     int r;
297     CERT_PKEY *cpk = s ? s->cert->key : ctx->cert->key;
298     if (!cpk)
299         return 0;
300     r = ssl_security_cert(s, ctx, x, 0, 0);
301     if (r != 1) {
302         SSLerr(SSL_F_SSL_CERT_ADD0_CHAIN_CERT, r);
303         return 0;
304     }
305     if (!cpk->chain)
306         cpk->chain = sk_X509_new_null();
307     if (!cpk->chain || !sk_X509_push(cpk->chain, x))
308         return 0;
309     return 1;
310 }
311 
312 int ssl_cert_add1_chain_cert(SSL *s, SSL_CTX *ctx, X509 *x)
313 {
314     if (!ssl_cert_add0_chain_cert(s, ctx, x))
315         return 0;
316     X509_up_ref(x);
317     return 1;
318 }
319 
320 int ssl_cert_select_current(CERT *c, X509 *x)
321 {
322     int i;
323     if (x == NULL)
324         return 0;
325     for (i = 0; i < SSL_PKEY_NUM; i++) {
326         CERT_PKEY *cpk = c->pkeys + i;
327         if (cpk->x509 == x && cpk->privatekey) {
328             c->key = cpk;
329             return 1;
330         }
331     }
332 
333     for (i = 0; i < SSL_PKEY_NUM; i++) {
334         CERT_PKEY *cpk = c->pkeys + i;
335         if (cpk->privatekey && cpk->x509 && !X509_cmp(cpk->x509, x)) {
336             c->key = cpk;
337             return 1;
338         }
339     }
340     return 0;
341 }
342 
343 int ssl_cert_set_current(CERT *c, long op)
344 {
345     int i, idx;
346     if (!c)
347         return 0;
348     if (op == SSL_CERT_SET_FIRST)
349         idx = 0;
350     else if (op == SSL_CERT_SET_NEXT) {
351         idx = (int)(c->key - c->pkeys + 1);
352         if (idx >= SSL_PKEY_NUM)
353             return 0;
354     } else
355         return 0;
356     for (i = idx; i < SSL_PKEY_NUM; i++) {
357         CERT_PKEY *cpk = c->pkeys + i;
358         if (cpk->x509 && cpk->privatekey) {
359             c->key = cpk;
360             return 1;
361         }
362     }
363     return 0;
364 }
365 
366 void ssl_cert_set_cert_cb(CERT *c, int (*cb) (SSL *ssl, void *arg), void *arg)
367 {
368     c->cert_cb = cb;
369     c->cert_cb_arg = arg;
370 }
371 
372 int ssl_verify_cert_chain(SSL *s, STACK_OF(X509) *sk)
373 {
374     X509 *x;
375     int i = 0;
376     X509_STORE *verify_store;
377     X509_STORE_CTX *ctx = NULL;
378     X509_VERIFY_PARAM *param;
379 
380     if ((sk == NULL) || (sk_X509_num(sk) == 0))
381         return 0;
382 
383     if (s->cert->verify_store)
384         verify_store = s->cert->verify_store;
385     else
386         verify_store = s->ctx->cert_store;
387 
388     ctx = X509_STORE_CTX_new();
389     if (ctx == NULL) {
390         SSLerr(SSL_F_SSL_VERIFY_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
391         return 0;
392     }
393 
394     x = sk_X509_value(sk, 0);
395     if (!X509_STORE_CTX_init(ctx, verify_store, x, sk)) {
396         SSLerr(SSL_F_SSL_VERIFY_CERT_CHAIN, ERR_R_X509_LIB);
397         goto end;
398     }
399     param = X509_STORE_CTX_get0_param(ctx);
400     /*
401      * XXX: Separate @AUTHSECLEVEL and @TLSSECLEVEL would be useful at some
402      * point, for now a single @SECLEVEL sets the same policy for TLS crypto
403      * and PKI authentication.
404      */
405     X509_VERIFY_PARAM_set_auth_level(param, SSL_get_security_level(s));
406 
407     /* Set suite B flags if needed */
408     X509_STORE_CTX_set_flags(ctx, tls1_suiteb(s));
409     if (!X509_STORE_CTX_set_ex_data
410         (ctx, SSL_get_ex_data_X509_STORE_CTX_idx(), s)) {
411         goto end;
412     }
413 
414     /* Verify via DANE if enabled */
415     if (DANETLS_ENABLED(&s->dane))
416         X509_STORE_CTX_set0_dane(ctx, &s->dane);
417 
418     /*
419      * We need to inherit the verify parameters. These can be determined by
420      * the context: if its a server it will verify SSL client certificates or
421      * vice versa.
422      */
423 
424     X509_STORE_CTX_set_default(ctx, s->server ? "ssl_client" : "ssl_server");
425     /*
426      * Anything non-default in "s->param" should overwrite anything in the ctx.
427      */
428     X509_VERIFY_PARAM_set1(param, s->param);
429 
430     if (s->verify_callback)
431         X509_STORE_CTX_set_verify_cb(ctx, s->verify_callback);
432 
433     if (s->ctx->app_verify_callback != NULL)
434         i = s->ctx->app_verify_callback(ctx, s->ctx->app_verify_arg);
435     else
436         i = X509_verify_cert(ctx);
437 
438     s->verify_result = X509_STORE_CTX_get_error(ctx);
439     sk_X509_pop_free(s->verified_chain, X509_free);
440     s->verified_chain = NULL;
441     if (X509_STORE_CTX_get0_chain(ctx) != NULL) {
442         s->verified_chain = X509_STORE_CTX_get1_chain(ctx);
443         if (s->verified_chain == NULL) {
444             SSLerr(SSL_F_SSL_VERIFY_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
445             i = 0;
446         }
447     }
448 
449     /* Move peername from the store context params to the SSL handle's */
450     X509_VERIFY_PARAM_move_peername(s->param, param);
451 
452  end:
453     X509_STORE_CTX_free(ctx);
454     return i;
455 }
456 
457 static void set_client_CA_list(STACK_OF(X509_NAME) **ca_list,
458                                STACK_OF(X509_NAME) *name_list)
459 {
460     sk_X509_NAME_pop_free(*ca_list, X509_NAME_free);
461     *ca_list = name_list;
462 }
463 
464 STACK_OF(X509_NAME) *SSL_dup_CA_list(STACK_OF(X509_NAME) *sk)
465 {
466     int i;
467     STACK_OF(X509_NAME) *ret;
468     X509_NAME *name;
469 
470     ret = sk_X509_NAME_new_null();
471     if (ret == NULL) {
472         SSLerr(SSL_F_SSL_DUP_CA_LIST, ERR_R_MALLOC_FAILURE);
473         return NULL;
474     }
475     for (i = 0; i < sk_X509_NAME_num(sk); i++) {
476         name = X509_NAME_dup(sk_X509_NAME_value(sk, i));
477         if (name == NULL || !sk_X509_NAME_push(ret, name)) {
478             sk_X509_NAME_pop_free(ret, X509_NAME_free);
479             X509_NAME_free(name);
480             return NULL;
481         }
482     }
483     return (ret);
484 }
485 
486 void SSL_set_client_CA_list(SSL *s, STACK_OF(X509_NAME) *name_list)
487 {
488     set_client_CA_list(&(s->client_CA), name_list);
489 }
490 
491 void SSL_CTX_set_client_CA_list(SSL_CTX *ctx, STACK_OF(X509_NAME) *name_list)
492 {
493     set_client_CA_list(&(ctx->client_CA), name_list);
494 }
495 
496 STACK_OF(X509_NAME) *SSL_CTX_get_client_CA_list(const SSL_CTX *ctx)
497 {
498     return (ctx->client_CA);
499 }
500 
501 STACK_OF(X509_NAME) *SSL_get_client_CA_list(const SSL *s)
502 {
503     if (!s->server) {           /* we are in the client */
504         if (((s->version >> 8) == SSL3_VERSION_MAJOR) && (s->s3 != NULL))
505             return (s->s3->tmp.ca_names);
506         else
507             return (NULL);
508     } else {
509         if (s->client_CA != NULL)
510             return (s->client_CA);
511         else
512             return (s->ctx->client_CA);
513     }
514 }
515 
516 static int add_client_CA(STACK_OF(X509_NAME) **sk, X509 *x)
517 {
518     X509_NAME *name;
519 
520     if (x == NULL)
521         return (0);
522     if ((*sk == NULL) && ((*sk = sk_X509_NAME_new_null()) == NULL))
523         return (0);
524 
525     if ((name = X509_NAME_dup(X509_get_subject_name(x))) == NULL)
526         return (0);
527 
528     if (!sk_X509_NAME_push(*sk, name)) {
529         X509_NAME_free(name);
530         return (0);
531     }
532     return (1);
533 }
534 
535 int SSL_add_client_CA(SSL *ssl, X509 *x)
536 {
537     return (add_client_CA(&(ssl->client_CA), x));
538 }
539 
540 int SSL_CTX_add_client_CA(SSL_CTX *ctx, X509 *x)
541 {
542     return (add_client_CA(&(ctx->client_CA), x));
543 }
544 
545 static int xname_sk_cmp(const X509_NAME *const *a, const X509_NAME *const *b)
546 {
547     return (X509_NAME_cmp(*a, *b));
548 }
549 
550 static int xname_cmp(const X509_NAME *a, const X509_NAME *b)
551 {
552     return X509_NAME_cmp(a, b);
553 }
554 
555 static unsigned long xname_hash(const X509_NAME *a)
556 {
557     return X509_NAME_hash((X509_NAME *)a);
558 }
559 
560 /**
561  * Load CA certs from a file into a ::STACK. Note that it is somewhat misnamed;
562  * it doesn't really have anything to do with clients (except that a common use
563  * for a stack of CAs is to send it to the client). Actually, it doesn't have
564  * much to do with CAs, either, since it will load any old cert.
565  * \param file the file containing one or more certs.
566  * \return a ::STACK containing the certs.
567  */
568 STACK_OF(X509_NAME) *SSL_load_client_CA_file(const char *file)
569 {
570     BIO *in = BIO_new(BIO_s_file());
571     X509 *x = NULL;
572     X509_NAME *xn = NULL;
573     STACK_OF(X509_NAME) *ret = NULL;
574     LHASH_OF(X509_NAME) *name_hash = lh_X509_NAME_new(xname_hash, xname_cmp);
575 
576     if ((name_hash == NULL) || (in == NULL)) {
577         SSLerr(SSL_F_SSL_LOAD_CLIENT_CA_FILE, ERR_R_MALLOC_FAILURE);
578         goto err;
579     }
580 
581     if (!BIO_read_filename(in, file))
582         goto err;
583 
584     for (;;) {
585         if (PEM_read_bio_X509(in, &x, NULL, NULL) == NULL)
586             break;
587         if (ret == NULL) {
588             ret = sk_X509_NAME_new_null();
589             if (ret == NULL) {
590                 SSLerr(SSL_F_SSL_LOAD_CLIENT_CA_FILE, ERR_R_MALLOC_FAILURE);
591                 goto err;
592             }
593         }
594         if ((xn = X509_get_subject_name(x)) == NULL)
595             goto err;
596         /* check for duplicates */
597         xn = X509_NAME_dup(xn);
598         if (xn == NULL)
599             goto err;
600         if (lh_X509_NAME_retrieve(name_hash, xn) != NULL) {
601             /* Duplicate. */
602             X509_NAME_free(xn);
603             xn = NULL;
604         } else {
605             lh_X509_NAME_insert(name_hash, xn);
606             if (!sk_X509_NAME_push(ret, xn))
607                 goto err;
608         }
609     }
610     goto done;
611 
612  err:
613     X509_NAME_free(xn);
614     sk_X509_NAME_pop_free(ret, X509_NAME_free);
615     ret = NULL;
616  done:
617     BIO_free(in);
618     X509_free(x);
619     lh_X509_NAME_free(name_hash);
620     if (ret != NULL)
621         ERR_clear_error();
622     return (ret);
623 }
624 
625 /**
626  * Add a file of certs to a stack.
627  * \param stack the stack to add to.
628  * \param file the file to add from. All certs in this file that are not
629  * already in the stack will be added.
630  * \return 1 for success, 0 for failure. Note that in the case of failure some
631  * certs may have been added to \c stack.
632  */
633 
634 int SSL_add_file_cert_subjects_to_stack(STACK_OF(X509_NAME) *stack,
635                                         const char *file)
636 {
637     BIO *in;
638     X509 *x = NULL;
639     X509_NAME *xn = NULL;
640     int ret = 1;
641     int (*oldcmp) (const X509_NAME *const *a, const X509_NAME *const *b);
642 
643     oldcmp = sk_X509_NAME_set_cmp_func(stack, xname_sk_cmp);
644 
645     in = BIO_new(BIO_s_file());
646 
647     if (in == NULL) {
648         SSLerr(SSL_F_SSL_ADD_FILE_CERT_SUBJECTS_TO_STACK, ERR_R_MALLOC_FAILURE);
649         goto err;
650     }
651 
652     if (!BIO_read_filename(in, file))
653         goto err;
654 
655     for (;;) {
656         if (PEM_read_bio_X509(in, &x, NULL, NULL) == NULL)
657             break;
658         if ((xn = X509_get_subject_name(x)) == NULL)
659             goto err;
660         xn = X509_NAME_dup(xn);
661         if (xn == NULL)
662             goto err;
663         if (sk_X509_NAME_find(stack, xn) >= 0) {
664             /* Duplicate. */
665             X509_NAME_free(xn);
666         } else if (!sk_X509_NAME_push(stack, xn)) {
667             X509_NAME_free(xn);
668             goto err;
669         }
670     }
671 
672     ERR_clear_error();
673     goto done;
674 
675  err:
676     ret = 0;
677  done:
678     BIO_free(in);
679     X509_free(x);
680     (void)sk_X509_NAME_set_cmp_func(stack, oldcmp);
681     return ret;
682 }
683 
684 /**
685  * Add a directory of certs to a stack.
686  * \param stack the stack to append to.
687  * \param dir the directory to append from. All files in this directory will be
688  * examined as potential certs. Any that are acceptable to
689  * SSL_add_dir_cert_subjects_to_stack() that are not already in the stack will be
690  * included.
691  * \return 1 for success, 0 for failure. Note that in the case of failure some
692  * certs may have been added to \c stack.
693  */
694 
695 int SSL_add_dir_cert_subjects_to_stack(STACK_OF(X509_NAME) *stack,
696                                        const char *dir)
697 {
698     OPENSSL_DIR_CTX *d = NULL;
699     const char *filename;
700     int ret = 0;
701 
702     /* Note that a side effect is that the CAs will be sorted by name */
703 
704     while ((filename = OPENSSL_DIR_read(&d, dir))) {
705         char buf[1024];
706         int r;
707 
708         if (strlen(dir) + strlen(filename) + 2 > sizeof(buf)) {
709             SSLerr(SSL_F_SSL_ADD_DIR_CERT_SUBJECTS_TO_STACK,
710                    SSL_R_PATH_TOO_LONG);
711             goto err;
712         }
713 #ifdef OPENSSL_SYS_VMS
714         r = BIO_snprintf(buf, sizeof(buf), "%s%s", dir, filename);
715 #else
716         r = BIO_snprintf(buf, sizeof(buf), "%s/%s", dir, filename);
717 #endif
718         if (r <= 0 || r >= (int)sizeof(buf))
719             goto err;
720         if (!SSL_add_file_cert_subjects_to_stack(stack, buf))
721             goto err;
722     }
723 
724     if (errno) {
725         SYSerr(SYS_F_OPENDIR, get_last_sys_error());
726         ERR_add_error_data(3, "OPENSSL_DIR_read(&ctx, '", dir, "')");
727         SSLerr(SSL_F_SSL_ADD_DIR_CERT_SUBJECTS_TO_STACK, ERR_R_SYS_LIB);
728         goto err;
729     }
730 
731     ret = 1;
732 
733  err:
734     if (d)
735         OPENSSL_DIR_end(&d);
736 
737     return ret;
738 }
739 
740 /* Add a certificate to a BUF_MEM structure */
741 
742 static int ssl_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x)
743 {
744     int n;
745     unsigned char *p;
746 
747     n = i2d_X509(x, NULL);
748     if (n < 0 || !BUF_MEM_grow_clean(buf, (int)(n + (*l) + 3))) {
749         SSLerr(SSL_F_SSL_ADD_CERT_TO_BUF, ERR_R_BUF_LIB);
750         return 0;
751     }
752     p = (unsigned char *)&(buf->data[*l]);
753     l2n3(n, p);
754     n = i2d_X509(x, &p);
755     if (n < 0) {
756         /* Shouldn't happen */
757         SSLerr(SSL_F_SSL_ADD_CERT_TO_BUF, ERR_R_BUF_LIB);
758         return 0;
759     }
760     *l += n + 3;
761 
762     return 1;
763 }
764 
765 /* Add certificate chain to internal SSL BUF_MEM structure */
766 int ssl_add_cert_chain(SSL *s, CERT_PKEY *cpk, unsigned long *l)
767 {
768     BUF_MEM *buf = s->init_buf;
769     int i, chain_count;
770     X509 *x;
771     STACK_OF(X509) *extra_certs;
772     STACK_OF(X509) *chain = NULL;
773     X509_STORE *chain_store;
774 
775     /* TLSv1 sends a chain with nothing in it, instead of an alert */
776     if (!BUF_MEM_grow_clean(buf, 10)) {
777         SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_BUF_LIB);
778         return 0;
779     }
780 
781     if (!cpk || !cpk->x509)
782         return 1;
783 
784     x = cpk->x509;
785 
786     /*
787      * If we have a certificate specific chain use it, else use parent ctx.
788      */
789     if (cpk->chain)
790         extra_certs = cpk->chain;
791     else
792         extra_certs = s->ctx->extra_certs;
793 
794     if ((s->mode & SSL_MODE_NO_AUTO_CHAIN) || extra_certs)
795         chain_store = NULL;
796     else if (s->cert->chain_store)
797         chain_store = s->cert->chain_store;
798     else
799         chain_store = s->ctx->cert_store;
800 
801     if (chain_store) {
802         X509_STORE_CTX *xs_ctx = X509_STORE_CTX_new();
803 
804         if (xs_ctx == NULL) {
805             SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
806             return (0);
807         }
808         if (!X509_STORE_CTX_init(xs_ctx, chain_store, x, NULL)) {
809             X509_STORE_CTX_free(xs_ctx);
810             SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_X509_LIB);
811             return (0);
812         }
813         /*
814          * It is valid for the chain not to be complete (because normally we
815          * don't include the root cert in the chain). Therefore we deliberately
816          * ignore the error return from this call. We're not actually verifying
817          * the cert - we're just building as much of the chain as we can
818          */
819         (void)X509_verify_cert(xs_ctx);
820         /* Don't leave errors in the queue */
821         ERR_clear_error();
822         chain = X509_STORE_CTX_get0_chain(xs_ctx);
823         i = ssl_security_cert_chain(s, chain, NULL, 0);
824         if (i != 1) {
825 #if 0
826             /* Dummy error calls so mkerr generates them */
827             SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_EE_KEY_TOO_SMALL);
828             SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_KEY_TOO_SMALL);
829             SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_MD_TOO_WEAK);
830 #endif
831             X509_STORE_CTX_free(xs_ctx);
832             SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i);
833             return 0;
834         }
835         chain_count = sk_X509_num(chain);
836         for (i = 0; i < chain_count; i++) {
837             x = sk_X509_value(chain, i);
838 
839             if (!ssl_add_cert_to_buf(buf, l, x)) {
840                 X509_STORE_CTX_free(xs_ctx);
841                 return 0;
842             }
843         }
844         X509_STORE_CTX_free(xs_ctx);
845     } else {
846         i = ssl_security_cert_chain(s, extra_certs, x, 0);
847         if (i != 1) {
848             SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i);
849             return 0;
850         }
851         if (!ssl_add_cert_to_buf(buf, l, x))
852             return 0;
853         for (i = 0; i < sk_X509_num(extra_certs); i++) {
854             x = sk_X509_value(extra_certs, i);
855             if (!ssl_add_cert_to_buf(buf, l, x))
856                 return 0;
857         }
858     }
859     return 1;
860 }
861 
862 /* Build a certificate chain for current certificate */
863 int ssl_build_cert_chain(SSL *s, SSL_CTX *ctx, int flags)
864 {
865     CERT *c = s ? s->cert : ctx->cert;
866     CERT_PKEY *cpk = c->key;
867     X509_STORE *chain_store = NULL;
868     X509_STORE_CTX *xs_ctx = NULL;
869     STACK_OF(X509) *chain = NULL, *untrusted = NULL;
870     X509 *x;
871     int i, rv = 0;
872     unsigned long error;
873 
874     if (!cpk->x509) {
875         SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, SSL_R_NO_CERTIFICATE_SET);
876         goto err;
877     }
878     /* Rearranging and check the chain: add everything to a store */
879     if (flags & SSL_BUILD_CHAIN_FLAG_CHECK) {
880         chain_store = X509_STORE_new();
881         if (chain_store == NULL)
882             goto err;
883         for (i = 0; i < sk_X509_num(cpk->chain); i++) {
884             x = sk_X509_value(cpk->chain, i);
885             if (!X509_STORE_add_cert(chain_store, x)) {
886                 error = ERR_peek_last_error();
887                 if (ERR_GET_LIB(error) != ERR_LIB_X509 ||
888                     ERR_GET_REASON(error) != X509_R_CERT_ALREADY_IN_HASH_TABLE)
889                     goto err;
890                 ERR_clear_error();
891             }
892         }
893         /* Add EE cert too: it might be self signed */
894         if (!X509_STORE_add_cert(chain_store, cpk->x509)) {
895             error = ERR_peek_last_error();
896             if (ERR_GET_LIB(error) != ERR_LIB_X509 ||
897                 ERR_GET_REASON(error) != X509_R_CERT_ALREADY_IN_HASH_TABLE)
898                 goto err;
899             ERR_clear_error();
900         }
901     } else {
902         if (c->chain_store)
903             chain_store = c->chain_store;
904         else if (s)
905             chain_store = s->ctx->cert_store;
906         else
907             chain_store = ctx->cert_store;
908 
909         if (flags & SSL_BUILD_CHAIN_FLAG_UNTRUSTED)
910             untrusted = cpk->chain;
911     }
912 
913     xs_ctx = X509_STORE_CTX_new();
914     if (xs_ctx == NULL) {
915         SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
916         goto err;
917     }
918     if (!X509_STORE_CTX_init(xs_ctx, chain_store, cpk->x509, untrusted)) {
919         SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, ERR_R_X509_LIB);
920         goto err;
921     }
922     /* Set suite B flags if needed */
923     X509_STORE_CTX_set_flags(xs_ctx,
924                              c->cert_flags & SSL_CERT_FLAG_SUITEB_128_LOS);
925 
926     i = X509_verify_cert(xs_ctx);
927     if (i <= 0 && flags & SSL_BUILD_CHAIN_FLAG_IGNORE_ERROR) {
928         if (flags & SSL_BUILD_CHAIN_FLAG_CLEAR_ERROR)
929             ERR_clear_error();
930         i = 1;
931         rv = 2;
932     }
933     if (i > 0)
934         chain = X509_STORE_CTX_get1_chain(xs_ctx);
935     if (i <= 0) {
936         SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, SSL_R_CERTIFICATE_VERIFY_FAILED);
937         i = X509_STORE_CTX_get_error(xs_ctx);
938         ERR_add_error_data(2, "Verify error:",
939                            X509_verify_cert_error_string(i));
940 
941         goto err;
942     }
943     /* Remove EE certificate from chain */
944     x = sk_X509_shift(chain);
945     X509_free(x);
946     if (flags & SSL_BUILD_CHAIN_FLAG_NO_ROOT) {
947         if (sk_X509_num(chain) > 0) {
948             /* See if last cert is self signed */
949             x = sk_X509_value(chain, sk_X509_num(chain) - 1);
950             if (X509_get_extension_flags(x) & EXFLAG_SS) {
951                 x = sk_X509_pop(chain);
952                 X509_free(x);
953             }
954         }
955     }
956     /*
957      * Check security level of all CA certificates: EE will have been checked
958      * already.
959      */
960     for (i = 0; i < sk_X509_num(chain); i++) {
961         x = sk_X509_value(chain, i);
962         rv = ssl_security_cert(s, ctx, x, 0, 0);
963         if (rv != 1) {
964             SSLerr(SSL_F_SSL_BUILD_CERT_CHAIN, rv);
965             sk_X509_pop_free(chain, X509_free);
966             rv = 0;
967             goto err;
968         }
969     }
970     sk_X509_pop_free(cpk->chain, X509_free);
971     cpk->chain = chain;
972     if (rv == 0)
973         rv = 1;
974  err:
975     if (flags & SSL_BUILD_CHAIN_FLAG_CHECK)
976         X509_STORE_free(chain_store);
977     X509_STORE_CTX_free(xs_ctx);
978 
979     return rv;
980 }
981 
982 int ssl_cert_set_cert_store(CERT *c, X509_STORE *store, int chain, int ref)
983 {
984     X509_STORE **pstore;
985     if (chain)
986         pstore = &c->chain_store;
987     else
988         pstore = &c->verify_store;
989     X509_STORE_free(*pstore);
990     *pstore = store;
991     if (ref && store)
992         X509_STORE_up_ref(store);
993     return 1;
994 }
995 
996 static int ssl_security_default_callback(const SSL *s, const SSL_CTX *ctx,
997                                          int op, int bits, int nid, void *other,
998                                          void *ex)
999 {
1000     int level, minbits;
1001     static const int minbits_table[5] = { 80, 112, 128, 192, 256 };
1002     if (ctx)
1003         level = SSL_CTX_get_security_level(ctx);
1004     else
1005         level = SSL_get_security_level(s);
1006 
1007     if (level <= 0) {
1008         /*
1009          * No EDH keys weaker than 1024-bits even at level 0, otherwise,
1010          * anything goes.
1011          */
1012         if (op == SSL_SECOP_TMP_DH && bits < 80)
1013             return 0;
1014         return 1;
1015     }
1016     if (level > 5)
1017         level = 5;
1018     minbits = minbits_table[level - 1];
1019     switch (op) {
1020     case SSL_SECOP_CIPHER_SUPPORTED:
1021     case SSL_SECOP_CIPHER_SHARED:
1022     case SSL_SECOP_CIPHER_CHECK:
1023         {
1024             const SSL_CIPHER *c = other;
1025             /* No ciphers below security level */
1026             if (bits < minbits)
1027                 return 0;
1028             /* No unauthenticated ciphersuites */
1029             if (c->algorithm_auth & SSL_aNULL)
1030                 return 0;
1031             /* No MD5 mac ciphersuites */
1032             if (c->algorithm_mac & SSL_MD5)
1033                 return 0;
1034             /* SHA1 HMAC is 160 bits of security */
1035             if (minbits > 160 && c->algorithm_mac & SSL_SHA1)
1036                 return 0;
1037             /* Level 2: no RC4 */
1038             if (level >= 2 && c->algorithm_enc == SSL_RC4)
1039                 return 0;
1040             /* Level 3: forward secure ciphersuites only */
1041             if (level >= 3 && !(c->algorithm_mkey & (SSL_kEDH | SSL_kEECDH)))
1042                 return 0;
1043             break;
1044         }
1045     case SSL_SECOP_VERSION:
1046         if (!SSL_IS_DTLS(s)) {
1047             /* SSLv3 not allowed at level 2 */
1048             if (nid <= SSL3_VERSION && level >= 2)
1049                 return 0;
1050             /* TLS v1.1 and above only for level 3 */
1051             if (nid <= TLS1_VERSION && level >= 3)
1052                 return 0;
1053             /* TLS v1.2 only for level 4 and above */
1054             if (nid <= TLS1_1_VERSION && level >= 4)
1055                 return 0;
1056         } else {
1057             /* DTLS v1.2 only for level 4 and above */
1058             if (DTLS_VERSION_LT(nid, DTLS1_2_VERSION) && level >= 4)
1059                 return 0;
1060         }
1061         break;
1062 
1063     case SSL_SECOP_COMPRESSION:
1064         if (level >= 2)
1065             return 0;
1066         break;
1067     case SSL_SECOP_TICKET:
1068         if (level >= 3)
1069             return 0;
1070         break;
1071     default:
1072         if (bits < minbits)
1073             return 0;
1074     }
1075     return 1;
1076 }
1077 
1078 int ssl_security(const SSL *s, int op, int bits, int nid, void *other)
1079 {
1080     return s->cert->sec_cb(s, NULL, op, bits, nid, other, s->cert->sec_ex);
1081 }
1082 
1083 int ssl_ctx_security(const SSL_CTX *ctx, int op, int bits, int nid, void *other)
1084 {
1085     return ctx->cert->sec_cb(NULL, ctx, op, bits, nid, other,
1086                              ctx->cert->sec_ex);
1087 }
1088