pk7_smime.c revision 296341
1/* pk7_smime.c */
2/*
3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
4 * project.
5 */
6/* ====================================================================
7 * Copyright (c) 1999-2004 The OpenSSL Project.  All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in
18 *    the documentation and/or other materials provided with the
19 *    distribution.
20 *
21 * 3. All advertising materials mentioning features or use of this
22 *    software must display the following acknowledgment:
23 *    "This product includes software developed by the OpenSSL Project
24 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 *
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 *    endorse or promote products derived from this software without
28 *    prior written permission. For written permission, please contact
29 *    licensing@OpenSSL.org.
30 *
31 * 5. Products derived from this software may not be called "OpenSSL"
32 *    nor may "OpenSSL" appear in their names without prior written
33 *    permission of the OpenSSL Project.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 *    acknowledgment:
37 *    "This product includes software developed by the OpenSSL Project
38 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
53 *
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com).  This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
57 *
58 */
59
60/* Simple PKCS#7 processing functions */
61
62#include <stdio.h>
63#include "cryptlib.h"
64#include <openssl/x509.h>
65#include <openssl/x509v3.h>
66
67static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si);
68
69PKCS7 *PKCS7_sign(X509 *signcert, EVP_PKEY *pkey, STACK_OF(X509) *certs,
70                  BIO *data, int flags)
71{
72    PKCS7 *p7;
73    int i;
74
75    if (!(p7 = PKCS7_new())) {
76        PKCS7err(PKCS7_F_PKCS7_SIGN, ERR_R_MALLOC_FAILURE);
77        return NULL;
78    }
79
80    if (!PKCS7_set_type(p7, NID_pkcs7_signed))
81        goto err;
82
83    if (!PKCS7_content_new(p7, NID_pkcs7_data))
84        goto err;
85
86    if (pkey && !PKCS7_sign_add_signer(p7, signcert, pkey, NULL, flags)) {
87        PKCS7err(PKCS7_F_PKCS7_SIGN, PKCS7_R_PKCS7_ADD_SIGNER_ERROR);
88        goto err;
89    }
90
91    if (!(flags & PKCS7_NOCERTS)) {
92        for (i = 0; i < sk_X509_num(certs); i++) {
93            if (!PKCS7_add_certificate(p7, sk_X509_value(certs, i)))
94                goto err;
95        }
96    }
97
98    if (flags & PKCS7_DETACHED)
99        PKCS7_set_detached(p7, 1);
100
101    if (flags & (PKCS7_STREAM | PKCS7_PARTIAL))
102        return p7;
103
104    if (PKCS7_final(p7, data, flags))
105        return p7;
106
107 err:
108    PKCS7_free(p7);
109    return NULL;
110}
111
112int PKCS7_final(PKCS7 *p7, BIO *data, int flags)
113{
114    BIO *p7bio;
115    int ret = 0;
116    if (!(p7bio = PKCS7_dataInit(p7, NULL))) {
117        PKCS7err(PKCS7_F_PKCS7_FINAL, ERR_R_MALLOC_FAILURE);
118        return 0;
119    }
120
121    SMIME_crlf_copy(data, p7bio, flags);
122
123    (void)BIO_flush(p7bio);
124
125    if (!PKCS7_dataFinal(p7, p7bio)) {
126        PKCS7err(PKCS7_F_PKCS7_FINAL, PKCS7_R_PKCS7_DATASIGN);
127        goto err;
128    }
129
130    ret = 1;
131
132 err:
133    BIO_free_all(p7bio);
134
135    return ret;
136
137}
138
139/* Check to see if a cipher exists and if so add S/MIME capabilities */
140
141static int add_cipher_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
142{
143    if (EVP_get_cipherbynid(nid))
144        return PKCS7_simple_smimecap(sk, nid, arg);
145    return 1;
146}
147
148static int add_digest_smcap(STACK_OF(X509_ALGOR) *sk, int nid, int arg)
149{
150    if (EVP_get_digestbynid(nid))
151        return PKCS7_simple_smimecap(sk, nid, arg);
152    return 1;
153}
154
155PKCS7_SIGNER_INFO *PKCS7_sign_add_signer(PKCS7 *p7, X509 *signcert,
156                                         EVP_PKEY *pkey, const EVP_MD *md,
157                                         int flags)
158{
159    PKCS7_SIGNER_INFO *si = NULL;
160    STACK_OF(X509_ALGOR) *smcap = NULL;
161    if (!X509_check_private_key(signcert, pkey)) {
162        PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
163                 PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
164        return NULL;
165    }
166
167    if (!(si = PKCS7_add_signature(p7, signcert, pkey, md))) {
168        PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER,
169                 PKCS7_R_PKCS7_ADD_SIGNATURE_ERROR);
170        return NULL;
171    }
172
173    if (!(flags & PKCS7_NOCERTS)) {
174        if (!PKCS7_add_certificate(p7, signcert))
175            goto err;
176    }
177
178    if (!(flags & PKCS7_NOATTR)) {
179        if (!PKCS7_add_attrib_content_type(si, NULL))
180            goto err;
181        /* Add SMIMECapabilities */
182        if (!(flags & PKCS7_NOSMIMECAP)) {
183            if (!(smcap = sk_X509_ALGOR_new_null())) {
184                PKCS7err(PKCS7_F_PKCS7_SIGN_ADD_SIGNER, ERR_R_MALLOC_FAILURE);
185                goto err;
186            }
187            if (!add_cipher_smcap(smcap, NID_aes_256_cbc, -1)
188                || !add_digest_smcap(smcap, NID_id_GostR3411_94, -1)
189                || !add_cipher_smcap(smcap, NID_id_Gost28147_89, -1)
190                || !add_cipher_smcap(smcap, NID_aes_192_cbc, -1)
191                || !add_cipher_smcap(smcap, NID_aes_128_cbc, -1)
192                || !add_cipher_smcap(smcap, NID_des_ede3_cbc, -1)
193                || !add_cipher_smcap(smcap, NID_rc2_cbc, 128)
194                || !add_cipher_smcap(smcap, NID_rc2_cbc, 64)
195                || !add_cipher_smcap(smcap, NID_des_cbc, -1)
196                || !add_cipher_smcap(smcap, NID_rc2_cbc, 40)
197                || !PKCS7_add_attrib_smimecap(si, smcap))
198                goto err;
199            sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
200            smcap = NULL;
201        }
202        if (flags & PKCS7_REUSE_DIGEST) {
203            if (!pkcs7_copy_existing_digest(p7, si))
204                goto err;
205            if (!(flags & PKCS7_PARTIAL) && !PKCS7_SIGNER_INFO_sign(si))
206                goto err;
207        }
208    }
209    return si;
210 err:
211    if (smcap)
212        sk_X509_ALGOR_pop_free(smcap, X509_ALGOR_free);
213    return NULL;
214}
215
216/*
217 * Search for a digest matching SignerInfo digest type and if found copy
218 * across.
219 */
220
221static int pkcs7_copy_existing_digest(PKCS7 *p7, PKCS7_SIGNER_INFO *si)
222{
223    int i;
224    STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
225    PKCS7_SIGNER_INFO *sitmp;
226    ASN1_OCTET_STRING *osdig = NULL;
227    sinfos = PKCS7_get_signer_info(p7);
228    for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
229        sitmp = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
230        if (si == sitmp)
231            break;
232        if (sk_X509_ATTRIBUTE_num(sitmp->auth_attr) <= 0)
233            continue;
234        if (!OBJ_cmp(si->digest_alg->algorithm, sitmp->digest_alg->algorithm)) {
235            osdig = PKCS7_digest_from_attributes(sitmp->auth_attr);
236            break;
237        }
238
239    }
240
241    if (osdig)
242        return PKCS7_add1_attrib_digest(si, osdig->data, osdig->length);
243
244    PKCS7err(PKCS7_F_PKCS7_COPY_EXISTING_DIGEST,
245             PKCS7_R_NO_MATCHING_DIGEST_TYPE_FOUND);
246    return 0;
247}
248
249int PKCS7_verify(PKCS7 *p7, STACK_OF(X509) *certs, X509_STORE *store,
250                 BIO *indata, BIO *out, int flags)
251{
252    STACK_OF(X509) *signers;
253    X509 *signer;
254    STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
255    PKCS7_SIGNER_INFO *si;
256    X509_STORE_CTX cert_ctx;
257    char buf[4096];
258    int i, j = 0, k, ret = 0;
259    BIO *p7bio;
260    BIO *tmpin, *tmpout;
261
262    if (!p7) {
263        PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_INVALID_NULL_POINTER);
264        return 0;
265    }
266
267    if (!PKCS7_type_is_signed(p7)) {
268        PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_WRONG_CONTENT_TYPE);
269        return 0;
270    }
271
272    /* Check for no data and no content: no data to verify signature */
273    if (PKCS7_get_detached(p7) && !indata) {
274        PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_CONTENT);
275        return 0;
276    }
277#if 0
278    /*
279     * NB: this test commented out because some versions of Netscape
280     * illegally include zero length content when signing data.
281     */
282
283    /* Check for data and content: two sets of data */
284    if (!PKCS7_get_detached(p7) && indata) {
285        PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_CONTENT_AND_DATA_PRESENT);
286        return 0;
287    }
288#endif
289
290    sinfos = PKCS7_get_signer_info(p7);
291
292    if (!sinfos || !sk_PKCS7_SIGNER_INFO_num(sinfos)) {
293        PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_NO_SIGNATURES_ON_DATA);
294        return 0;
295    }
296
297    signers = PKCS7_get0_signers(p7, certs, flags);
298
299    if (!signers)
300        return 0;
301
302    /* Now verify the certificates */
303
304    if (!(flags & PKCS7_NOVERIFY))
305        for (k = 0; k < sk_X509_num(signers); k++) {
306            signer = sk_X509_value(signers, k);
307            if (!(flags & PKCS7_NOCHAIN)) {
308                if (!X509_STORE_CTX_init(&cert_ctx, store, signer,
309                                         p7->d.sign->cert)) {
310                    PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
311                    sk_X509_free(signers);
312                    return 0;
313                }
314                X509_STORE_CTX_set_default(&cert_ctx, "smime_sign");
315            } else if (!X509_STORE_CTX_init(&cert_ctx, store, signer, NULL)) {
316                PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_X509_LIB);
317                sk_X509_free(signers);
318                return 0;
319            }
320            if (!(flags & PKCS7_NOCRL))
321                X509_STORE_CTX_set0_crls(&cert_ctx, p7->d.sign->crl);
322            i = X509_verify_cert(&cert_ctx);
323            if (i <= 0)
324                j = X509_STORE_CTX_get_error(&cert_ctx);
325            X509_STORE_CTX_cleanup(&cert_ctx);
326            if (i <= 0) {
327                PKCS7err(PKCS7_F_PKCS7_VERIFY,
328                         PKCS7_R_CERTIFICATE_VERIFY_ERROR);
329                ERR_add_error_data(2, "Verify error:",
330                                   X509_verify_cert_error_string(j));
331                sk_X509_free(signers);
332                return 0;
333            }
334            /* Check for revocation status here */
335        }
336
337    /*
338     * Performance optimization: if the content is a memory BIO then store
339     * its contents in a temporary read only memory BIO. This avoids
340     * potentially large numbers of slow copies of data which will occur when
341     * reading from a read write memory BIO when signatures are calculated.
342     */
343
344    if (indata && (BIO_method_type(indata) == BIO_TYPE_MEM)) {
345        char *ptr;
346        long len;
347        len = BIO_get_mem_data(indata, &ptr);
348        tmpin = BIO_new_mem_buf(ptr, len);
349        if (tmpin == NULL) {
350            PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
351            return 0;
352        }
353    } else
354        tmpin = indata;
355
356    if (!(p7bio = PKCS7_dataInit(p7, tmpin)))
357        goto err;
358
359    if (flags & PKCS7_TEXT) {
360        if (!(tmpout = BIO_new(BIO_s_mem()))) {
361            PKCS7err(PKCS7_F_PKCS7_VERIFY, ERR_R_MALLOC_FAILURE);
362            goto err;
363        }
364        BIO_set_mem_eof_return(tmpout, 0);
365    } else
366        tmpout = out;
367
368    /* We now have to 'read' from p7bio to calculate digests etc. */
369    for (;;) {
370        i = BIO_read(p7bio, buf, sizeof(buf));
371        if (i <= 0)
372            break;
373        if (tmpout)
374            BIO_write(tmpout, buf, i);
375    }
376
377    if (flags & PKCS7_TEXT) {
378        if (!SMIME_text(tmpout, out)) {
379            PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SMIME_TEXT_ERROR);
380            BIO_free(tmpout);
381            goto err;
382        }
383        BIO_free(tmpout);
384    }
385
386    /* Now Verify All Signatures */
387    if (!(flags & PKCS7_NOSIGS))
388        for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
389            si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
390            signer = sk_X509_value(signers, i);
391            j = PKCS7_signatureVerify(p7bio, p7, si, signer);
392            if (j <= 0) {
393                PKCS7err(PKCS7_F_PKCS7_VERIFY, PKCS7_R_SIGNATURE_FAILURE);
394                goto err;
395            }
396        }
397
398    ret = 1;
399
400 err:
401
402    if (tmpin == indata) {
403        if (indata)
404            BIO_pop(p7bio);
405    }
406    BIO_free_all(p7bio);
407
408    sk_X509_free(signers);
409
410    return ret;
411}
412
413STACK_OF(X509) *PKCS7_get0_signers(PKCS7 *p7, STACK_OF(X509) *certs,
414                                   int flags)
415{
416    STACK_OF(X509) *signers;
417    STACK_OF(PKCS7_SIGNER_INFO) *sinfos;
418    PKCS7_SIGNER_INFO *si;
419    PKCS7_ISSUER_AND_SERIAL *ias;
420    X509 *signer;
421    int i;
422
423    if (!p7) {
424        PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_INVALID_NULL_POINTER);
425        return NULL;
426    }
427
428    if (!PKCS7_type_is_signed(p7)) {
429        PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_WRONG_CONTENT_TYPE);
430        return NULL;
431    }
432
433    /* Collect all the signers together */
434
435    sinfos = PKCS7_get_signer_info(p7);
436
437    if (sk_PKCS7_SIGNER_INFO_num(sinfos) <= 0) {
438        PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, PKCS7_R_NO_SIGNERS);
439        return 0;
440    }
441
442    if (!(signers = sk_X509_new_null())) {
443        PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS, ERR_R_MALLOC_FAILURE);
444        return NULL;
445    }
446
447    for (i = 0; i < sk_PKCS7_SIGNER_INFO_num(sinfos); i++) {
448        si = sk_PKCS7_SIGNER_INFO_value(sinfos, i);
449        ias = si->issuer_and_serial;
450        signer = NULL;
451        /* If any certificates passed they take priority */
452        if (certs)
453            signer = X509_find_by_issuer_and_serial(certs,
454                                                    ias->issuer, ias->serial);
455        if (!signer && !(flags & PKCS7_NOINTERN)
456            && p7->d.sign->cert)
457            signer =
458                X509_find_by_issuer_and_serial(p7->d.sign->cert,
459                                               ias->issuer, ias->serial);
460        if (!signer) {
461            PKCS7err(PKCS7_F_PKCS7_GET0_SIGNERS,
462                     PKCS7_R_SIGNER_CERTIFICATE_NOT_FOUND);
463            sk_X509_free(signers);
464            return 0;
465        }
466
467        if (!sk_X509_push(signers, signer)) {
468            sk_X509_free(signers);
469            return NULL;
470        }
471    }
472    return signers;
473}
474
475/* Build a complete PKCS#7 enveloped data */
476
477PKCS7 *PKCS7_encrypt(STACK_OF(X509) *certs, BIO *in, const EVP_CIPHER *cipher,
478                     int flags)
479{
480    PKCS7 *p7;
481    BIO *p7bio = NULL;
482    int i;
483    X509 *x509;
484    if (!(p7 = PKCS7_new())) {
485        PKCS7err(PKCS7_F_PKCS7_ENCRYPT, ERR_R_MALLOC_FAILURE);
486        return NULL;
487    }
488
489    if (!PKCS7_set_type(p7, NID_pkcs7_enveloped))
490        goto err;
491    if (!PKCS7_set_cipher(p7, cipher)) {
492        PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_SETTING_CIPHER);
493        goto err;
494    }
495
496    for (i = 0; i < sk_X509_num(certs); i++) {
497        x509 = sk_X509_value(certs, i);
498        if (!PKCS7_add_recipient(p7, x509)) {
499            PKCS7err(PKCS7_F_PKCS7_ENCRYPT, PKCS7_R_ERROR_ADDING_RECIPIENT);
500            goto err;
501        }
502    }
503
504    if (flags & PKCS7_STREAM)
505        return p7;
506
507    if (PKCS7_final(p7, in, flags))
508        return p7;
509
510 err:
511
512    BIO_free_all(p7bio);
513    PKCS7_free(p7);
514    return NULL;
515
516}
517
518int PKCS7_decrypt(PKCS7 *p7, EVP_PKEY *pkey, X509 *cert, BIO *data, int flags)
519{
520    BIO *tmpmem;
521    int ret, i;
522    char buf[4096];
523
524    if (!p7) {
525        PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_INVALID_NULL_POINTER);
526        return 0;
527    }
528
529    if (!PKCS7_type_is_enveloped(p7)) {
530        PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_WRONG_CONTENT_TYPE);
531        return 0;
532    }
533
534    if (cert && !X509_check_private_key(cert, pkey)) {
535        PKCS7err(PKCS7_F_PKCS7_DECRYPT,
536                 PKCS7_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
537        return 0;
538    }
539
540    if (!(tmpmem = PKCS7_dataDecode(p7, pkey, NULL, cert))) {
541        PKCS7err(PKCS7_F_PKCS7_DECRYPT, PKCS7_R_DECRYPT_ERROR);
542        return 0;
543    }
544
545    if (flags & PKCS7_TEXT) {
546        BIO *tmpbuf, *bread;
547        /* Encrypt BIOs can't do BIO_gets() so add a buffer BIO */
548        if (!(tmpbuf = BIO_new(BIO_f_buffer()))) {
549            PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
550            BIO_free_all(tmpmem);
551            return 0;
552        }
553        if (!(bread = BIO_push(tmpbuf, tmpmem))) {
554            PKCS7err(PKCS7_F_PKCS7_DECRYPT, ERR_R_MALLOC_FAILURE);
555            BIO_free_all(tmpbuf);
556            BIO_free_all(tmpmem);
557            return 0;
558        }
559        ret = SMIME_text(bread, data);
560        if (ret > 0 && BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
561            if (!BIO_get_cipher_status(tmpmem))
562                ret = 0;
563        }
564        BIO_free_all(bread);
565        return ret;
566    } else {
567        for (;;) {
568            i = BIO_read(tmpmem, buf, sizeof(buf));
569            if (i <= 0) {
570                ret = 1;
571                if (BIO_method_type(tmpmem) == BIO_TYPE_CIPHER) {
572                    if (!BIO_get_cipher_status(tmpmem))
573                        ret = 0;
574                }
575
576                break;
577            }
578            if (BIO_write(data, buf, i) != i) {
579                ret = 0;
580                break;
581            }
582        }
583        BIO_free_all(tmpmem);
584        return ret;
585    }
586}
587