1/*
2 * Copyright 1995-2021 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#include <stdio.h>
11#include "internal/cryptlib.h"
12#include <openssl/asn1.h>
13#include <openssl/objects.h>
14#include <openssl/x509.h>
15#include <openssl/x509v3.h>
16#include "crypto/x509.h"
17
18int X509_issuer_and_serial_cmp(const X509 *a, const X509 *b)
19{
20    int i;
21    const X509_CINF *ai, *bi;
22
23    ai = &a->cert_info;
24    bi = &b->cert_info;
25    i = ASN1_INTEGER_cmp(&ai->serialNumber, &bi->serialNumber);
26    if (i)
27        return i;
28    return X509_NAME_cmp(ai->issuer, bi->issuer);
29}
30
31#ifndef OPENSSL_NO_MD5
32unsigned long X509_issuer_and_serial_hash(X509 *a)
33{
34    unsigned long ret = 0;
35    EVP_MD_CTX *ctx = EVP_MD_CTX_new();
36    unsigned char md[16];
37    char *f;
38
39    if (ctx == NULL)
40        goto err;
41    f = X509_NAME_oneline(a->cert_info.issuer, NULL, 0);
42    if (f == NULL)
43        goto err;
44    if (!EVP_DigestInit_ex(ctx, EVP_md5(), NULL))
45        goto err;
46    if (!EVP_DigestUpdate(ctx, (unsigned char *)f, strlen(f)))
47        goto err;
48    OPENSSL_free(f);
49    if (!EVP_DigestUpdate
50        (ctx, (unsigned char *)a->cert_info.serialNumber.data,
51         (unsigned long)a->cert_info.serialNumber.length))
52        goto err;
53    if (!EVP_DigestFinal_ex(ctx, &(md[0]), NULL))
54        goto err;
55    ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
56           ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
57        ) & 0xffffffffL;
58 err:
59    EVP_MD_CTX_free(ctx);
60    return ret;
61}
62#endif
63
64int X509_issuer_name_cmp(const X509 *a, const X509 *b)
65{
66    return X509_NAME_cmp(a->cert_info.issuer, b->cert_info.issuer);
67}
68
69int X509_subject_name_cmp(const X509 *a, const X509 *b)
70{
71    return X509_NAME_cmp(a->cert_info.subject, b->cert_info.subject);
72}
73
74int X509_CRL_cmp(const X509_CRL *a, const X509_CRL *b)
75{
76    return X509_NAME_cmp(a->crl.issuer, b->crl.issuer);
77}
78
79int X509_CRL_match(const X509_CRL *a, const X509_CRL *b)
80{
81    return memcmp(a->sha1_hash, b->sha1_hash, 20);
82}
83
84X509_NAME *X509_get_issuer_name(const X509 *a)
85{
86    return a->cert_info.issuer;
87}
88
89unsigned long X509_issuer_name_hash(X509 *x)
90{
91    return X509_NAME_hash(x->cert_info.issuer);
92}
93
94#ifndef OPENSSL_NO_MD5
95unsigned long X509_issuer_name_hash_old(X509 *x)
96{
97    return X509_NAME_hash_old(x->cert_info.issuer);
98}
99#endif
100
101X509_NAME *X509_get_subject_name(const X509 *a)
102{
103    return a->cert_info.subject;
104}
105
106ASN1_INTEGER *X509_get_serialNumber(X509 *a)
107{
108    return &a->cert_info.serialNumber;
109}
110
111const ASN1_INTEGER *X509_get0_serialNumber(const X509 *a)
112{
113    return &a->cert_info.serialNumber;
114}
115
116unsigned long X509_subject_name_hash(X509 *x)
117{
118    return X509_NAME_hash(x->cert_info.subject);
119}
120
121#ifndef OPENSSL_NO_MD5
122unsigned long X509_subject_name_hash_old(X509 *x)
123{
124    return X509_NAME_hash_old(x->cert_info.subject);
125}
126#endif
127
128/*
129 * Compare two certificates: they must be identical for this to work. NB:
130 * Although "cmp" operations are generally prototyped to take "const"
131 * arguments (eg. for use in STACKs), the way X509 handling is - these
132 * operations may involve ensuring the hashes are up-to-date and ensuring
133 * certain cert information is cached. So this is the point where the
134 * "depth-first" constification tree has to halt with an evil cast.
135 */
136int X509_cmp(const X509 *a, const X509 *b)
137{
138    int rv = 0;
139
140    if (a == b) /* for efficiency */
141        return 0;
142
143    /* try to make sure hash is valid */
144    (void)X509_check_purpose((X509 *)a, -1, 0);
145    (void)X509_check_purpose((X509 *)b, -1, 0);
146
147    if ((a->ex_flags & EXFLAG_NO_FINGERPRINT) == 0
148            && (b->ex_flags & EXFLAG_NO_FINGERPRINT) == 0)
149        rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
150    if (rv != 0)
151        return rv;
152
153    /* Check for match against stored encoding too */
154    if (!a->cert_info.enc.modified && !b->cert_info.enc.modified) {
155        if (a->cert_info.enc.len < b->cert_info.enc.len)
156            return -1;
157        if (a->cert_info.enc.len > b->cert_info.enc.len)
158            return 1;
159        return memcmp(a->cert_info.enc.enc, b->cert_info.enc.enc,
160                      a->cert_info.enc.len);
161    }
162    return rv;
163}
164
165int X509_NAME_cmp(const X509_NAME *a, const X509_NAME *b)
166{
167    int ret;
168
169    /* Ensure canonical encoding is present and up to date */
170
171    if (!a->canon_enc || a->modified) {
172        ret = i2d_X509_NAME((X509_NAME *)a, NULL);
173        if (ret < 0)
174            return -2;
175    }
176
177    if (!b->canon_enc || b->modified) {
178        ret = i2d_X509_NAME((X509_NAME *)b, NULL);
179        if (ret < 0)
180            return -2;
181    }
182
183    ret = a->canon_enclen - b->canon_enclen;
184
185    if (ret != 0 || a->canon_enclen == 0)
186        return ret;
187
188    return memcmp(a->canon_enc, b->canon_enc, a->canon_enclen);
189
190}
191
192unsigned long X509_NAME_hash(X509_NAME *x)
193{
194    unsigned long ret = 0;
195    unsigned char md[SHA_DIGEST_LENGTH];
196
197    /* Make sure X509_NAME structure contains valid cached encoding */
198    i2d_X509_NAME(x, NULL);
199    if (!EVP_Digest(x->canon_enc, x->canon_enclen, md, NULL, EVP_sha1(),
200                    NULL))
201        return 0;
202
203    ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
204           ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
205        ) & 0xffffffffL;
206    return ret;
207}
208
209#ifndef OPENSSL_NO_MD5
210/*
211 * I now DER encode the name and hash it.  Since I cache the DER encoding,
212 * this is reasonably efficient.
213 */
214
215unsigned long X509_NAME_hash_old(X509_NAME *x)
216{
217    EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
218    unsigned long ret = 0;
219    unsigned char md[16];
220
221    if (md_ctx == NULL)
222        return ret;
223
224    /* Make sure X509_NAME structure contains valid cached encoding */
225    i2d_X509_NAME(x, NULL);
226    EVP_MD_CTX_set_flags(md_ctx, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
227    if (EVP_DigestInit_ex(md_ctx, EVP_md5(), NULL)
228        && EVP_DigestUpdate(md_ctx, x->bytes->data, x->bytes->length)
229        && EVP_DigestFinal_ex(md_ctx, md, NULL))
230        ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
231               ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
232            ) & 0xffffffffL;
233    EVP_MD_CTX_free(md_ctx);
234
235    return ret;
236}
237#endif
238
239/* Search a stack of X509 for a match */
240X509 *X509_find_by_issuer_and_serial(STACK_OF(X509) *sk, X509_NAME *name,
241                                     ASN1_INTEGER *serial)
242{
243    int i;
244    X509 x, *x509 = NULL;
245
246    if (!sk)
247        return NULL;
248
249    x.cert_info.serialNumber = *serial;
250    x.cert_info.issuer = name;
251
252    for (i = 0; i < sk_X509_num(sk); i++) {
253        x509 = sk_X509_value(sk, i);
254        if (X509_issuer_and_serial_cmp(x509, &x) == 0)
255            return x509;
256    }
257    return NULL;
258}
259
260X509 *X509_find_by_subject(STACK_OF(X509) *sk, X509_NAME *name)
261{
262    X509 *x509;
263    int i;
264
265    for (i = 0; i < sk_X509_num(sk); i++) {
266        x509 = sk_X509_value(sk, i);
267        if (X509_NAME_cmp(X509_get_subject_name(x509), name) == 0)
268            return x509;
269    }
270    return NULL;
271}
272
273EVP_PKEY *X509_get0_pubkey(const X509 *x)
274{
275    if (x == NULL)
276        return NULL;
277    return X509_PUBKEY_get0(x->cert_info.key);
278}
279
280EVP_PKEY *X509_get_pubkey(X509 *x)
281{
282    if (x == NULL)
283        return NULL;
284    return X509_PUBKEY_get(x->cert_info.key);
285}
286
287int X509_check_private_key(const X509 *x, const EVP_PKEY *k)
288{
289    const EVP_PKEY *xk;
290    int ret;
291
292    xk = X509_get0_pubkey(x);
293
294    if (xk)
295        ret = EVP_PKEY_cmp(xk, k);
296    else
297        ret = -2;
298
299    switch (ret) {
300    case 1:
301        break;
302    case 0:
303        X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_KEY_VALUES_MISMATCH);
304        break;
305    case -1:
306        X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_KEY_TYPE_MISMATCH);
307        break;
308    case -2:
309        X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_UNKNOWN_KEY_TYPE);
310    }
311    if (ret > 0)
312        return 1;
313    return 0;
314}
315
316/*
317 * Check a suite B algorithm is permitted: pass in a public key and the NID
318 * of its signature (or 0 if no signature). The pflags is a pointer to a
319 * flags field which must contain the suite B verification flags.
320 */
321
322#ifndef OPENSSL_NO_EC
323
324static int check_suite_b(EVP_PKEY *pkey, int sign_nid, unsigned long *pflags)
325{
326    const EC_GROUP *grp = NULL;
327    int curve_nid;
328    if (pkey && EVP_PKEY_id(pkey) == EVP_PKEY_EC)
329        grp = EC_KEY_get0_group(EVP_PKEY_get0_EC_KEY(pkey));
330    if (!grp)
331        return X509_V_ERR_SUITE_B_INVALID_ALGORITHM;
332    curve_nid = EC_GROUP_get_curve_name(grp);
333    /* Check curve is consistent with LOS */
334    if (curve_nid == NID_secp384r1) { /* P-384 */
335        /*
336         * Check signature algorithm is consistent with curve.
337         */
338        if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA384)
339            return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
340        if (!(*pflags & X509_V_FLAG_SUITEB_192_LOS))
341            return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
342        /* If we encounter P-384 we cannot use P-256 later */
343        *pflags &= ~X509_V_FLAG_SUITEB_128_LOS_ONLY;
344    } else if (curve_nid == NID_X9_62_prime256v1) { /* P-256 */
345        if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA256)
346            return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
347        if (!(*pflags & X509_V_FLAG_SUITEB_128_LOS_ONLY))
348            return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
349    } else
350        return X509_V_ERR_SUITE_B_INVALID_CURVE;
351
352    return X509_V_OK;
353}
354
355int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
356                            unsigned long flags)
357{
358    int rv, i, sign_nid;
359    EVP_PKEY *pk;
360    unsigned long tflags = flags;
361
362    if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
363        return X509_V_OK;
364
365    /* If no EE certificate passed in must be first in chain */
366    if (x == NULL) {
367        x = sk_X509_value(chain, 0);
368        i = 1;
369    } else
370        i = 0;
371
372    pk = X509_get0_pubkey(x);
373
374    /*
375     * With DANE-EE(3) success, or DANE-EE(3)/PKIX-EE(1) failure we don't build
376     * a chain all, just report trust success or failure, but must also report
377     * Suite-B errors if applicable.  This is indicated via a NULL chain
378     * pointer.  All we need to do is check the leaf key algorithm.
379     */
380    if (chain == NULL)
381        return check_suite_b(pk, -1, &tflags);
382
383    if (X509_get_version(x) != 2) {
384        rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
385        /* Correct error depth */
386        i = 0;
387        goto end;
388    }
389
390    /* Check EE key only */
391    rv = check_suite_b(pk, -1, &tflags);
392    if (rv != X509_V_OK) {
393        /* Correct error depth */
394        i = 0;
395        goto end;
396    }
397    for (; i < sk_X509_num(chain); i++) {
398        sign_nid = X509_get_signature_nid(x);
399        x = sk_X509_value(chain, i);
400        if (X509_get_version(x) != 2) {
401            rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
402            goto end;
403        }
404        pk = X509_get0_pubkey(x);
405        rv = check_suite_b(pk, sign_nid, &tflags);
406        if (rv != X509_V_OK)
407            goto end;
408    }
409
410    /* Final check: root CA signature */
411    rv = check_suite_b(pk, X509_get_signature_nid(x), &tflags);
412 end:
413    if (rv != X509_V_OK) {
414        /* Invalid signature or LOS errors are for previous cert */
415        if ((rv == X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM
416             || rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED) && i)
417            i--;
418        /*
419         * If we have LOS error and flags changed then we are signing P-384
420         * with P-256. Use more meaningful error.
421         */
422        if (rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED && flags != tflags)
423            rv = X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256;
424        if (perror_depth)
425            *perror_depth = i;
426    }
427    return rv;
428}
429
430int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
431{
432    int sign_nid;
433    if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
434        return X509_V_OK;
435    sign_nid = OBJ_obj2nid(crl->crl.sig_alg.algorithm);
436    return check_suite_b(pk, sign_nid, &flags);
437}
438
439#else
440int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
441                            unsigned long flags)
442{
443    return 0;
444}
445
446int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
447{
448    return 0;
449}
450
451#endif
452/*
453 * Not strictly speaking an "up_ref" as a STACK doesn't have a reference
454 * count but it has the same effect by duping the STACK and upping the ref of
455 * each X509 structure.
456 */
457STACK_OF(X509) *X509_chain_up_ref(STACK_OF(X509) *chain)
458{
459    STACK_OF(X509) *ret;
460    int i;
461    ret = sk_X509_dup(chain);
462    if (ret == NULL)
463        return NULL;
464    for (i = 0; i < sk_X509_num(ret); i++) {
465        X509 *x = sk_X509_value(ret, i);
466        if (!X509_up_ref(x))
467            goto err;
468    }
469    return ret;
470 err:
471    while (i-- > 0)
472        X509_free (sk_X509_value(ret, i));
473    sk_X509_free(ret);
474    return NULL;
475}
476