xref: /freebsd/crypto/krb5/src/tests/fuzzing/fuzz_pac.c (revision f1c4c3daccbaf3820f0e2224de53df12fc952fcc)
1 /* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
2 /* tests/fuzzing/fuzz_pac.c */
3 /*
4  * Copyright (C) 2024 by Arjun. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * * Redistributions of source code must retain the above copyright
11  *   notice, this list of conditions and the following disclaimer.
12  *
13  * * Redistributions in binary form must reproduce the above copyright
14  *   notice, this list of conditions and the following disclaimer in
15  *   the documentation and/or other materials provided with the
16  *   distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
23  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
27  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
29  * OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Fuzzing harness implementation for krb5_pac_parse.
34  */
35 
36 #include "autoconf.h"
37 #include <k5-int.h>
38 
39 #define U(x) (uint8_t *)x
40 #define kMinInputLength 2
41 #define kMaxInputLength 1024
42 
43 static const krb5_keyblock kdc_keyblock = {
44     0, ENCTYPE_ARCFOUR_HMAC,
45     16, U("\xB2\x86\x75\x71\x48\xAF\x7F\xD2\x52\xC5\x36\x03\xA1\x50\xB7\xE7")
46 };
47 
48 static const krb5_keyblock member_keyblock = {
49     0, ENCTYPE_ARCFOUR_HMAC,
50     16, U("\xD2\x17\xFA\xEA\xE5\xE6\xB5\xF9\x5C\xCC\x94\x07\x7A\xB8\xA5\xFC")
51 };
52 
53 static time_t authtime = 1120440609;
54 static const char *user = "w2003final$@WIN2K3.THINKER.LOCAL";
55 
56 extern int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
57 
58 int
LLVMFuzzerTestOneInput(const uint8_t * data,size_t size)59 LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
60 {
61     krb5_error_code ret;
62     krb5_context context = NULL;
63     krb5_pac pac;
64     krb5_principal princ = NULL;
65 
66     if (size < kMinInputLength || size > kMaxInputLength)
67         return 0;
68 
69     ret = krb5_init_context(&context);
70     if (ret)
71         return 0;
72 
73     ret = krb5_parse_name(context, user, &princ);
74     if (ret)
75         goto cleanup;
76 
77     ret = krb5_pac_parse(context, data, size, &pac);
78     if (ret)
79         goto cleanup;
80 
81     krb5_pac_verify(context, pac, authtime, princ, NULL, NULL);
82     krb5_pac_verify_ext(context, pac, authtime, princ, NULL, NULL, TRUE);
83     krb5_pac_verify(context, pac, authtime, princ, &member_keyblock,
84                     &kdc_keyblock);
85 
86     krb5_pac_free(context, pac);
87 
88 cleanup:
89     krb5_free_principal(context, princ);
90     krb5_free_context(context);
91 
92     return 0;
93 }
94