1 /*
2  * Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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 #include <stdio.h>
11 #include <stdlib.h>
12 #include <string.h>
13 #include "apps.h"
14 #include "progs.h"
15 #include <openssl/bio.h>
16 #include <openssl/err.h>
17 #include <openssl/x509.h>
18 #include <openssl/x509v3.h>
19 #include <openssl/pem.h>
20 
21 static int cb(int ok, X509_STORE_CTX *ctx);
22 static int check(X509_STORE *ctx, const char *file,
23                  STACK_OF(X509) *uchain, STACK_OF(X509) *tchain,
24                  STACK_OF(X509_CRL) *crls, int show_chain,
25                  STACK_OF(OPENSSL_STRING) *opts);
26 static int v_verbose = 0, vflags = 0;
27 
28 typedef enum OPTION_choice {
29     OPT_COMMON,
30     OPT_ENGINE, OPT_CAPATH, OPT_CAFILE, OPT_CASTORE,
31     OPT_NOCAPATH, OPT_NOCAFILE, OPT_NOCASTORE,
32     OPT_UNTRUSTED, OPT_TRUSTED, OPT_CRLFILE, OPT_CRL_DOWNLOAD, OPT_SHOW_CHAIN,
33     OPT_V_ENUM, OPT_NAMEOPT, OPT_VFYOPT,
34     OPT_VERBOSE,
35     OPT_PROV_ENUM
36 } OPTION_CHOICE;
37 
38 const OPTIONS verify_options[] = {
39     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [cert...]\n"},
40 
41     OPT_SECTION("General"),
42     {"help", OPT_HELP, '-', "Display this summary"},
43 #ifndef OPENSSL_NO_ENGINE
44     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
45 #endif
46     {"verbose", OPT_VERBOSE, '-',
47         "Print extra information about the operations being performed."},
48     {"nameopt", OPT_NAMEOPT, 's', "Certificate subject/issuer name printing options"},
49 
50     OPT_SECTION("Certificate chain"),
51     {"trusted", OPT_TRUSTED, '<', "A file of trusted certificates"},
52     {"CAfile", OPT_CAFILE, '<', "A file of trusted certificates"},
53     {"CApath", OPT_CAPATH, '/', "A directory of files with trusted certificates"},
54     {"CAstore", OPT_CASTORE, ':', "URI to a store of trusted certificates"},
55     {"no-CAfile", OPT_NOCAFILE, '-',
56      "Do not load the default trusted certificates file"},
57     {"no-CApath", OPT_NOCAPATH, '-',
58      "Do not load trusted certificates from the default directory"},
59     {"no-CAstore", OPT_NOCASTORE, '-',
60      "Do not load trusted certificates from the default certificates store"},
61     {"untrusted", OPT_UNTRUSTED, '<', "A file of untrusted certificates"},
62     {"CRLfile", OPT_CRLFILE, '<',
63         "File containing one or more CRL's (in PEM format) to load"},
64     {"crl_download", OPT_CRL_DOWNLOAD, '-',
65         "Try downloading CRL information for certificates via their CDP entries"},
66     {"show_chain", OPT_SHOW_CHAIN, '-',
67         "Display information about the certificate chain"},
68 
69     OPT_V_OPTIONS,
70     {"vfyopt", OPT_VFYOPT, 's', "Verification parameter in n:v form"},
71 
72     OPT_PROV_OPTIONS,
73 
74     OPT_PARAMETERS(),
75     {"cert", 0, 0, "Certificate(s) to verify (optional; stdin used otherwise)"},
76     {NULL}
77 };
78 
verify_main(int argc,char ** argv)79 int verify_main(int argc, char **argv)
80 {
81     ENGINE *e = NULL;
82     STACK_OF(X509) *untrusted = NULL, *trusted = NULL;
83     STACK_OF(X509_CRL) *crls = NULL;
84     STACK_OF(OPENSSL_STRING) *vfyopts = NULL;
85     X509_STORE *store = NULL;
86     X509_VERIFY_PARAM *vpm = NULL;
87     const char *prog, *CApath = NULL, *CAfile = NULL, *CAstore = NULL;
88     int noCApath = 0, noCAfile = 0, noCAstore = 0;
89     int vpmtouched = 0, crl_download = 0, show_chain = 0, i = 0, ret = 1;
90     OPTION_CHOICE o;
91 
92     if ((vpm = X509_VERIFY_PARAM_new()) == NULL)
93         goto end;
94 
95     prog = opt_init(argc, argv, verify_options);
96     while ((o = opt_next()) != OPT_EOF) {
97         switch (o) {
98         case OPT_EOF:
99         case OPT_ERR:
100  opthelp:
101             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
102             goto end;
103         case OPT_HELP:
104             opt_help(verify_options);
105             BIO_printf(bio_err, "\nRecognized certificate chain purposes:\n");
106             for (i = 0; i < X509_PURPOSE_get_count(); i++) {
107                 X509_PURPOSE *ptmp = X509_PURPOSE_get0(i);
108 
109                 BIO_printf(bio_err, "  %-15s  %s\n",
110                         X509_PURPOSE_get0_sname(ptmp),
111                         X509_PURPOSE_get0_name(ptmp));
112             }
113 
114             BIO_printf(bio_err, "Recognized certificate policy names:\n");
115             for (i = 0; i < X509_VERIFY_PARAM_get_count(); i++) {
116                 const X509_VERIFY_PARAM *vptmp = X509_VERIFY_PARAM_get0(i);
117 
118                 BIO_printf(bio_err, "  %s\n",
119                         X509_VERIFY_PARAM_get0_name(vptmp));
120             }
121             ret = 0;
122             goto end;
123         case OPT_V_CASES:
124             if (!opt_verify(o, vpm))
125                 goto end;
126             vpmtouched++;
127             break;
128         case OPT_CAPATH:
129             CApath = opt_arg();
130             break;
131         case OPT_CAFILE:
132             CAfile = opt_arg();
133             break;
134         case OPT_CASTORE:
135             CAstore = opt_arg();
136             break;
137         case OPT_NOCAPATH:
138             noCApath = 1;
139             break;
140         case OPT_NOCAFILE:
141             noCAfile = 1;
142             break;
143         case OPT_NOCASTORE:
144             noCAstore = 1;
145             break;
146         case OPT_UNTRUSTED:
147             /* Zero or more times */
148             if (!load_certs(opt_arg(), 0, &untrusted, NULL,
149                             "untrusted certificates"))
150                 goto end;
151             break;
152         case OPT_TRUSTED:
153             /* Zero or more times */
154             noCAfile = 1;
155             noCApath = 1;
156             noCAstore = 1;
157             if (!load_certs(opt_arg(), 0, &trusted, NULL, "trusted certificates"))
158                 goto end;
159             break;
160         case OPT_CRLFILE:
161             /* Zero or more times */
162             if (!load_crls(opt_arg(), &crls, NULL, "other CRLs"))
163                 goto end;
164             break;
165         case OPT_CRL_DOWNLOAD:
166             crl_download = 1;
167             break;
168         case OPT_ENGINE:
169             if ((e = setup_engine(opt_arg(), 0)) == NULL) {
170                 /* Failure message already displayed */
171                 goto end;
172             }
173             break;
174         case OPT_SHOW_CHAIN:
175             show_chain = 1;
176             break;
177         case OPT_NAMEOPT:
178             if (!set_nameopt(opt_arg()))
179                 goto end;
180             break;
181         case OPT_VFYOPT:
182             if (!vfyopts)
183                 vfyopts = sk_OPENSSL_STRING_new_null();
184             if (!vfyopts || !sk_OPENSSL_STRING_push(vfyopts, opt_arg()))
185                 goto opthelp;
186             break;
187         case OPT_VERBOSE:
188             v_verbose = 1;
189             break;
190         case OPT_PROV_CASES:
191             if (!opt_provider(o))
192                 goto end;
193             break;
194         }
195     }
196 
197     /* Extra arguments are certificates to verify. */
198     argc = opt_num_rest();
199     argv = opt_rest();
200 
201     if (trusted != NULL
202         && (CAfile != NULL || CApath != NULL || CAstore != NULL)) {
203         BIO_printf(bio_err,
204                    "%s: Cannot use -trusted with -CAfile, -CApath or -CAstore\n",
205                    prog);
206         goto end;
207     }
208 
209     if ((store = setup_verify(CAfile, noCAfile, CApath, noCApath,
210                               CAstore, noCAstore)) == NULL)
211         goto end;
212     X509_STORE_set_verify_cb(store, cb);
213 
214     if (vpmtouched)
215         X509_STORE_set1_param(store, vpm);
216 
217     ERR_clear_error();
218 
219     if (crl_download)
220         store_setup_crl_download(store);
221 
222     ret = 0;
223     if (argc < 1) {
224         if (check(store, NULL, untrusted, trusted, crls, show_chain,
225                   vfyopts) != 1)
226             ret = -1;
227     } else {
228         for (i = 0; i < argc; i++)
229             if (check(store, argv[i], untrusted, trusted, crls, show_chain,
230                       vfyopts) != 1)
231                 ret = -1;
232     }
233 
234  end:
235     X509_VERIFY_PARAM_free(vpm);
236     X509_STORE_free(store);
237     sk_X509_pop_free(untrusted, X509_free);
238     sk_X509_pop_free(trusted, X509_free);
239     sk_X509_CRL_pop_free(crls, X509_CRL_free);
240     sk_OPENSSL_STRING_free(vfyopts);
241     release_engine(e);
242     return (ret < 0 ? 2 : ret);
243 }
244 
check(X509_STORE * ctx,const char * file,STACK_OF (X509)* uchain,STACK_OF (X509)* tchain,STACK_OF (X509_CRL)* crls,int show_chain,STACK_OF (OPENSSL_STRING)* opts)245 static int check(X509_STORE *ctx, const char *file,
246                  STACK_OF(X509) *uchain, STACK_OF(X509) *tchain,
247                  STACK_OF(X509_CRL) *crls, int show_chain,
248                  STACK_OF(OPENSSL_STRING) *opts)
249 {
250     X509 *x = NULL;
251     int i = 0, ret = 0;
252     X509_STORE_CTX *csc;
253     STACK_OF(X509) *chain = NULL;
254     int num_untrusted;
255 
256     x = load_cert(file, FORMAT_UNDEF, "certificate file");
257     if (x == NULL)
258         goto end;
259 
260     if (opts != NULL) {
261         for (i = 0; i < sk_OPENSSL_STRING_num(opts); i++) {
262             char *opt = sk_OPENSSL_STRING_value(opts, i);
263             if (x509_ctrl_string(x, opt) <= 0) {
264                 BIO_printf(bio_err, "parameter error \"%s\"\n", opt);
265                 ERR_print_errors(bio_err);
266                 X509_free(x);
267                 return 0;
268             }
269         }
270     }
271 
272     csc = X509_STORE_CTX_new();
273     if (csc == NULL) {
274         BIO_printf(bio_err, "error %s: X.509 store context allocation failed\n",
275                    (file == NULL) ? "stdin" : file);
276         goto end;
277     }
278 
279     X509_STORE_set_flags(ctx, vflags);
280     if (!X509_STORE_CTX_init(csc, ctx, x, uchain)) {
281         X509_STORE_CTX_free(csc);
282         BIO_printf(bio_err,
283                    "error %s: X.509 store context initialization failed\n",
284                    (file == NULL) ? "stdin" : file);
285         goto end;
286     }
287     if (tchain != NULL)
288         X509_STORE_CTX_set0_trusted_stack(csc, tchain);
289     if (crls != NULL)
290         X509_STORE_CTX_set0_crls(csc, crls);
291     i = X509_verify_cert(csc);
292     if (i > 0 && X509_STORE_CTX_get_error(csc) == X509_V_OK) {
293         BIO_printf(bio_out, "%s: OK\n", (file == NULL) ? "stdin" : file);
294         ret = 1;
295         if (show_chain) {
296             int j;
297 
298             chain = X509_STORE_CTX_get1_chain(csc);
299             num_untrusted = X509_STORE_CTX_get_num_untrusted(csc);
300             BIO_printf(bio_out, "Chain:\n");
301             for (j = 0; j < sk_X509_num(chain); j++) {
302                 X509 *cert = sk_X509_value(chain, j);
303                 BIO_printf(bio_out, "depth=%d: ", j);
304                 X509_NAME_print_ex_fp(stdout,
305                                       X509_get_subject_name(cert),
306                                       0, get_nameopt());
307                 if (j < num_untrusted)
308                     BIO_printf(bio_out, " (untrusted)");
309                 BIO_printf(bio_out, "\n");
310             }
311             sk_X509_pop_free(chain, X509_free);
312         }
313     } else {
314         BIO_printf(bio_err,
315                    "error %s: verification failed\n",
316                    (file == NULL) ? "stdin" : file);
317     }
318     X509_STORE_CTX_free(csc);
319 
320  end:
321     if (i <= 0)
322         ERR_print_errors(bio_err);
323     X509_free(x);
324 
325     return ret;
326 }
327 
cb(int ok,X509_STORE_CTX * ctx)328 static int cb(int ok, X509_STORE_CTX *ctx)
329 {
330     int cert_error = X509_STORE_CTX_get_error(ctx);
331     X509 *current_cert = X509_STORE_CTX_get_current_cert(ctx);
332 
333     if (!ok) {
334         if (current_cert != NULL) {
335             X509_NAME_print_ex(bio_err,
336                             X509_get_subject_name(current_cert),
337                             0, get_nameopt());
338             BIO_printf(bio_err, "\n");
339         }
340         BIO_printf(bio_err, "%serror %d at %d depth lookup: %s\n",
341                X509_STORE_CTX_get0_parent_ctx(ctx) ? "[CRL path] " : "",
342                cert_error,
343                X509_STORE_CTX_get_error_depth(ctx),
344                X509_verify_cert_error_string(cert_error));
345 
346         /*
347          * Pretend that some errors are ok, so they don't stop further
348          * processing of the certificate chain.  Setting ok = 1 does this.
349          * After X509_verify_cert() is done, we verify that there were
350          * no actual errors, even if the returned value was positive.
351          */
352         switch (cert_error) {
353         case X509_V_ERR_NO_EXPLICIT_POLICY:
354             policies_print(ctx);
355             /* fall thru */
356         case X509_V_ERR_CERT_HAS_EXPIRED:
357             /* Continue even if the leaf is a self-signed cert */
358         case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
359             /* Continue after extension errors too */
360         case X509_V_ERR_INVALID_CA:
361         case X509_V_ERR_INVALID_NON_CA:
362         case X509_V_ERR_PATH_LENGTH_EXCEEDED:
363         case X509_V_ERR_CRL_HAS_EXPIRED:
364         case X509_V_ERR_CRL_NOT_YET_VALID:
365         case X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION:
366             /* errors due to strict conformance checking (-x509_strict) */
367         case X509_V_ERR_INVALID_PURPOSE:
368         case X509_V_ERR_PATHLEN_INVALID_FOR_NON_CA:
369         case X509_V_ERR_PATHLEN_WITHOUT_KU_KEY_CERT_SIGN:
370         case X509_V_ERR_CA_BCONS_NOT_CRITICAL:
371         case X509_V_ERR_CA_CERT_MISSING_KEY_USAGE:
372         case X509_V_ERR_KU_KEY_CERT_SIGN_INVALID_FOR_NON_CA:
373         case X509_V_ERR_ISSUER_NAME_EMPTY:
374         case X509_V_ERR_SUBJECT_NAME_EMPTY:
375         case X509_V_ERR_EMPTY_SUBJECT_SAN_NOT_CRITICAL:
376         case X509_V_ERR_EMPTY_SUBJECT_ALT_NAME:
377         case X509_V_ERR_SIGNATURE_ALGORITHM_INCONSISTENCY:
378         case X509_V_ERR_AUTHORITY_KEY_IDENTIFIER_CRITICAL:
379         case X509_V_ERR_SUBJECT_KEY_IDENTIFIER_CRITICAL:
380         case X509_V_ERR_MISSING_AUTHORITY_KEY_IDENTIFIER:
381         case X509_V_ERR_MISSING_SUBJECT_KEY_IDENTIFIER:
382         case X509_V_ERR_EXTENSIONS_REQUIRE_VERSION_3:
383             ok = 1;
384         }
385         return ok;
386 
387     }
388     if (cert_error == X509_V_OK && ok == 2)
389         policies_print(ctx);
390     if (!v_verbose)
391         ERR_clear_error();
392     return ok;
393 }
394