xref: /freebsd/crypto/krb5/src/lib/krb5/krb/princ_comp.c (revision 7f2fe78b9dd5f51c821d771b63d2e096f6fd49e9)
1 /* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
2 /* lib/krb5/krb/princ_comp.c - Compare two principals for equality */
3 /*
4  * Copyright 1990,1991,2007 by the Massachusetts Institute of Technology.
5  * All Rights Reserved.
6  *
7  * Export of this software from the United States of America may
8  *   require a specific license from the United States Government.
9  *   It is the responsibility of any person or organization contemplating
10  *   export to obtain such a license before exporting.
11  *
12  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
13  * distribute this software and its documentation for any purpose and
14  * without fee is hereby granted, provided that the above copyright
15  * notice appear in all copies and that both that copyright notice and
16  * this permission notice appear in supporting documentation, and that
17  * the name of M.I.T. not be used in advertising or publicity pertaining
18  * to distribution of the software without specific, written prior
19  * permission.  Furthermore if you modify this software you must label
20  * your software as modified software and not distribute it in such a
21  * fashion that it might be confused with the original M.I.T. software.
22  * M.I.T. makes no representations about the suitability of
23  * this software for any purpose.  It is provided "as is" without express
24  * or implied warranty.
25  */
26 
27 #include "k5-int.h"
28 #include "k5-unicode.h"
29 
30 static krb5_boolean
realm_compare_flags(krb5_context context,krb5_const_principal princ1,krb5_const_principal princ2,int flags)31 realm_compare_flags(krb5_context context,
32                     krb5_const_principal princ1,
33                     krb5_const_principal princ2,
34                     int flags)
35 {
36     const krb5_data *realm1 = &princ1->realm;
37     const krb5_data *realm2 = &princ2->realm;
38 
39     if (realm1->length != realm2->length)
40         return FALSE;
41     if (realm1->length == 0)
42         return TRUE;
43 
44     return (flags & KRB5_PRINCIPAL_COMPARE_CASEFOLD) ?
45         (strncasecmp(realm1->data, realm2->data, realm2->length) == 0) :
46         (memcmp(realm1->data, realm2->data, realm2->length) == 0);
47 }
48 
49 krb5_boolean KRB5_CALLCONV
krb5_realm_compare(krb5_context context,krb5_const_principal princ1,krb5_const_principal princ2)50 krb5_realm_compare(krb5_context context, krb5_const_principal princ1, krb5_const_principal princ2)
51 {
52     return realm_compare_flags(context, princ1, princ2, 0);
53 }
54 
55 static krb5_error_code
upn_to_principal(krb5_context context,krb5_const_principal princ,krb5_principal * upn)56 upn_to_principal(krb5_context context,
57                  krb5_const_principal princ,
58                  krb5_principal *upn)
59 {
60     char *unparsed_name;
61     krb5_error_code code;
62 
63     code = krb5_unparse_name_flags(context, princ,
64                                    KRB5_PRINCIPAL_UNPARSE_NO_REALM,
65                                    &unparsed_name);
66     if (code) {
67         *upn = NULL;
68         return code;
69     }
70 
71     code = krb5_parse_name(context, unparsed_name, upn);
72 
73     free(unparsed_name);
74 
75     return code;
76 }
77 
78 krb5_boolean KRB5_CALLCONV
krb5_principal_compare_flags(krb5_context context,krb5_const_principal princ1,krb5_const_principal princ2,int flags)79 krb5_principal_compare_flags(krb5_context context,
80                              krb5_const_principal princ1,
81                              krb5_const_principal princ2,
82                              int flags)
83 {
84     krb5_int32 i;
85     unsigned int utf8 = (flags & KRB5_PRINCIPAL_COMPARE_UTF8) != 0;
86     unsigned int casefold = (flags & KRB5_PRINCIPAL_COMPARE_CASEFOLD) != 0;
87     krb5_principal upn1 = NULL;
88     krb5_principal upn2 = NULL;
89     krb5_boolean ret = FALSE;
90 
91     if (flags & KRB5_PRINCIPAL_COMPARE_ENTERPRISE) {
92         /* Treat UPNs as if they were real principals */
93         if (princ1->type == KRB5_NT_ENTERPRISE_PRINCIPAL) {
94             if (upn_to_principal(context, princ1, &upn1) == 0)
95                 princ1 = upn1;
96         }
97         if (princ2->type == KRB5_NT_ENTERPRISE_PRINCIPAL) {
98             if (upn_to_principal(context, princ2, &upn2) == 0)
99                 princ2 = upn2;
100         }
101     }
102 
103     if (princ1->length != princ2->length)
104         goto out;
105 
106     if ((flags & KRB5_PRINCIPAL_COMPARE_IGNORE_REALM) == 0 &&
107         !realm_compare_flags(context, princ1, princ2, flags))
108         goto out;
109 
110     for (i = 0; i < princ1->length; i++) {
111         const krb5_data *p1 = &princ1->data[i];
112         const krb5_data *p2 = &princ2->data[i];
113         krb5_boolean eq;
114 
115         if (casefold) {
116             if (utf8)
117                 eq = (krb5int_utf8_normcmp(p1, p2, KRB5_UTF8_CASEFOLD) == 0);
118             else
119                 eq = (p1->length == p2->length
120                       && strncasecmp(p1->data, p2->data, p2->length) == 0);
121         } else
122             eq = data_eq(*p1, *p2);
123 
124         if (!eq)
125             goto out;
126     }
127 
128     ret = TRUE;
129 
130 out:
131     if (upn1 != NULL)
132         krb5_free_principal(context, upn1);
133     if (upn2 != NULL)
134         krb5_free_principal(context, upn2);
135 
136     return ret;
137 }
138 
krb5_is_referral_realm(const krb5_data * r)139 krb5_boolean KRB5_CALLCONV krb5_is_referral_realm(const krb5_data *r)
140 {
141     /*
142      * Check for a match with KRB5_REFERRAL_REALM.  Currently this relies
143      * on that string constant being zero-length.  (Unlike principal realm
144      * names, KRB5_REFERRAL_REALM is known to be a string.)
145      */
146     assert(strlen(KRB5_REFERRAL_REALM)==0);
147     if (r->length==0)
148         return TRUE;
149     else
150         return FALSE;
151 }
152 
153 krb5_boolean KRB5_CALLCONV
krb5_principal_compare(krb5_context context,krb5_const_principal princ1,krb5_const_principal princ2)154 krb5_principal_compare(krb5_context context,
155                        krb5_const_principal princ1,
156                        krb5_const_principal princ2)
157 {
158     return krb5_principal_compare_flags(context, princ1, princ2, 0);
159 }
160 
161 krb5_boolean KRB5_CALLCONV
krb5_principal_compare_any_realm(krb5_context context,krb5_const_principal princ1,krb5_const_principal princ2)162 krb5_principal_compare_any_realm(krb5_context context,
163                                  krb5_const_principal princ1,
164                                  krb5_const_principal princ2)
165 {
166     return krb5_principal_compare_flags(context, princ1, princ2, KRB5_PRINCIPAL_COMPARE_IGNORE_REALM);
167 }
168