1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)ucred.h 8.4 (Berkeley) 1/9/95
32 */
33
34 #ifndef _SYS_UCRED_H_
35 #define _SYS_UCRED_H_
36
37 #include <sys/types.h>
38 #if defined(_KERNEL) || defined(_WANT_UCRED)
39 #include <sys/_lock.h>
40 #include <sys/_mutex.h>
41 #endif
42 #include <bsm/audit.h>
43
44 struct loginclass;
45
46 #define XU_NGROUPS 16
47
48 #if defined(_KERNEL) || defined(_WANT_UCRED)
49 /*
50 * Number of groups inlined in 'struct ucred'. It must stay reasonably low as
51 * it is also used by some functions to allocate an array of this size on the
52 * stack.
53 */
54 #define CRED_SMALLGROUPS_NB 16
55
56 /*
57 * Credentials.
58 *
59 * Please do not inspect cr_uid directly to determine superuserness. The
60 * priv(9) interface should be used to check for privilege.
61 *
62 * Lock reference:
63 * c - cr_mtx
64 *
65 * Unmarked fields are constant after creation.
66 *
67 * See "Credential management" comment in kern_prot.c for more information.
68 */
69 struct ucred {
70 struct mtx cr_mtx;
71 u_int cr_ref; /* (c) reference count */
72 u_int cr_users; /* (c) proc + thread using this cred */
73 struct auditinfo_addr cr_audit; /* Audit properties. */
74 #define cr_startcopy cr_uid
75 uid_t cr_uid; /* effective user id */
76 uid_t cr_ruid; /* real user id */
77 uid_t cr_svuid; /* saved user id */
78 /*
79 * XXXOC: On the next ABI change, please move 'cr_ngroups' out of the
80 * copied area (crcopy() already copes with this change).
81 */
82 int cr_ngroups; /* number of groups */
83 gid_t cr_rgid; /* real group id */
84 gid_t cr_svgid; /* saved group id */
85 struct uidinfo *cr_uidinfo; /* per euid resource consumption */
86 struct uidinfo *cr_ruidinfo; /* per ruid resource consumption */
87 struct prison *cr_prison; /* jail(2) */
88 struct loginclass *cr_loginclass; /* login class */
89 u_int cr_flags; /* credential flags */
90 void *cr_pspare2[2]; /* general use 2 */
91 #define cr_endcopy cr_label
92 struct label *cr_label; /* MAC label */
93 gid_t *cr_groups; /* groups */
94 int cr_agroups; /* Available groups */
95 /* storage for small groups */
96 gid_t cr_smallgroups[CRED_SMALLGROUPS_NB];
97 };
98 #define NOCRED ((struct ucred *)0) /* no credential available */
99 #define FSCRED ((struct ucred *)-1) /* filesystem credential */
100 #endif /* _KERNEL || _WANT_UCRED */
101
102 /*
103 * Flags for cr_flags.
104 */
105 #define CRED_FLAG_CAPMODE 0x00000001 /* In capability mode. */
106
107 /*
108 * This is the external representation of struct ucred.
109 */
110 struct xucred {
111 u_int cr_version; /* structure layout version */
112 uid_t cr_uid; /* effective user id */
113 short cr_ngroups; /* number of groups */
114 gid_t cr_groups[XU_NGROUPS]; /* groups */
115 union {
116 void *_cr_unused1; /* compatibility with old ucred */
117 pid_t cr_pid;
118 };
119 };
120 #define XUCRED_VERSION 0
121
122 /* This can be used for both ucred and xucred structures. */
123 #define cr_gid cr_groups[0]
124
125 #ifdef _KERNEL
126 struct proc;
127 struct thread;
128
129 struct credbatch {
130 struct ucred *cred;
131 int users;
132 int ref;
133 };
134
135 static inline void
credbatch_prep(struct credbatch * crb)136 credbatch_prep(struct credbatch *crb)
137 {
138 crb->cred = NULL;
139 crb->users = 0;
140 crb->ref = 0;
141 }
142 void credbatch_add(struct credbatch *crb, struct thread *td);
143
144 static inline void
credbatch_process(struct credbatch * crb __unused)145 credbatch_process(struct credbatch *crb __unused)
146 {
147
148 }
149
150 void credbatch_final(struct credbatch *crb);
151
152 void change_egid(struct ucred *newcred, gid_t egid);
153 void change_euid(struct ucred *newcred, struct uidinfo *euip);
154 void change_rgid(struct ucred *newcred, gid_t rgid);
155 void change_ruid(struct ucred *newcred, struct uidinfo *ruip);
156 void change_svgid(struct ucred *newcred, gid_t svgid);
157 void change_svuid(struct ucred *newcred, uid_t svuid);
158 void crcopy(struct ucred *dest, struct ucred *src);
159 struct ucred *crcopysafe(struct proc *p, struct ucred *cr);
160 struct ucred *crdup(struct ucred *cr);
161 void crextend(struct ucred *cr, int n);
162 void proc_set_cred(struct proc *p, struct ucred *newcred);
163 bool proc_set_cred_enforce_proc_lim(struct proc *p, struct ucred *newcred);
164 void proc_unset_cred(struct proc *p, bool decrement_proc_count);
165 void crfree(struct ucred *cr);
166 struct ucred *crcowsync(void);
167 struct ucred *crget(void);
168 struct ucred *crhold(struct ucred *cr);
169 struct ucred *crcowget(struct ucred *cr);
170 void crcowfree(struct thread *td);
171 void cru2x(struct ucred *cr, struct xucred *xcr);
172 void cru2xt(struct thread *td, struct xucred *xcr);
173 void crsetgroups(struct ucred *cr, int ngrp, const gid_t *groups);
174 void crsetgroups_fallback(struct ucred *cr, int ngrp, const gid_t *groups,
175 const gid_t fallback);
176
177 /*
178 * Returns whether gid designates a primary group in cred.
179 */
180 static inline int
group_is_primary(const gid_t gid,const struct ucred * const cred)181 group_is_primary(const gid_t gid, const struct ucred *const cred)
182 {
183 return (gid == cred->cr_groups[0] || gid == cred->cr_rgid ||
184 gid == cred->cr_svgid);
185 }
186 int group_is_supplementary(const gid_t gid, const struct ucred *const cred);
187 int groupmember(gid_t gid, const struct ucred *cred);
188 int realgroupmember(gid_t gid, const struct ucred *cred);
189 #endif /* _KERNEL */
190
191 #endif /* !_SYS_UCRED_H_ */
192