xref: /freebsd/sys/compat/linux/linux_uid16.c (revision ee2ea5ceafed78a5bd9810beb9e3ca927180c226)
1 /*-
2  * Copyright (c) 2001  The FreeBSD Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include "opt_compat.h"
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/lock.h>
34 #include <sys/mutex.h>
35 #include <sys/proc.h>
36 #include <sys/sysproto.h>
37 
38 #include <machine/../linux/linux.h>
39 #include <machine/../linux/linux_proto.h>
40 #include <compat/linux/linux_util.h>
41 
42 DUMMY(setfsuid16);
43 DUMMY(setfsgid16);
44 DUMMY(getresuid16);
45 DUMMY(getresgid16);
46 
47 #define	CAST_NOCHG(x)	(x == 0xFFFF) ? -1 : x;
48 
49 int
50 linux_chown16(struct thread *td, struct linux_chown16_args *args)
51 {
52 	struct chown_args bsd;
53 	caddr_t sg;
54 
55 	sg = stackgap_init();
56 	CHECKALTEXIST(td, &sg, args->path);
57 
58 #ifdef DEBUG
59 	if (ldebug(chown16))
60 		printf(ARGS(chown16, "%s, %d, %d"), args->path, args->uid,
61 		    args->gid);
62 #endif
63 
64 	bsd.path = args->path;
65 	bsd.uid = CAST_NOCHG(args->uid);
66 	bsd.gid = CAST_NOCHG(args->gid);
67 	return (chown(td, &bsd));
68 }
69 
70 int
71 linux_lchown16(struct thread *td, struct linux_lchown16_args *args)
72 {
73 	struct lchown_args bsd;
74 	caddr_t sg;
75 
76 	sg = stackgap_init();
77 	CHECKALTEXIST(td, &sg, args->path);
78 
79 #ifdef DEBUG
80 	if (ldebug(lchown16))
81 		printf(ARGS(lchown16, "%s, %d, %d"), args->path, args->uid,
82 		    args->gid);
83 #endif
84 
85 	bsd.path = args->path;
86 	bsd.uid = CAST_NOCHG(args->uid);
87 	bsd.gid = CAST_NOCHG(args->gid);
88 	return (lchown(td, &bsd));
89 }
90 
91 int
92 linux_setgroups16(struct thread *td, struct linux_setgroups16_args *args)
93 {
94 	struct ucred *newcred, *oldcred;
95 	l_gid16_t linux_gidset[NGROUPS];
96 	gid_t *bsd_gidset;
97 	int ngrp, error;
98 	struct proc *p;
99 
100 #ifdef DEBUG
101 	if (ldebug(setgroups16))
102 		printf(ARGS(setgroups16, "%d, *"), args->gidsetsize);
103 #endif
104 
105 	ngrp = args->gidsetsize;
106 	if (ngrp >= NGROUPS)
107 		return (EINVAL);
108 	error = copyin((caddr_t)args->gidset, linux_gidset,
109 	    ngrp * sizeof(l_gid16_t));
110 	if (error)
111 		return (error);
112 	newcred = crget();
113 	p = td->td_proc;
114 	PROC_LOCK(p);
115 	oldcred = p->p_ucred;
116 
117 	/*
118 	 * cr_groups[0] holds egid. Setting the whole set from
119 	 * the supplied set will cause egid to be changed too.
120 	 * Keep cr_groups[0] unchanged to prevent that.
121 	 */
122 
123 	if ((error = suser_cred(oldcred, PRISON_ROOT)) != 0) {
124 		PROC_UNLOCK(p);
125 		crfree(newcred);
126 		return (error);
127 	}
128 
129 	crcopy(newcred, oldcred);
130 	if (ngrp > 0) {
131 		newcred->cr_ngroups = ngrp + 1;
132 
133 		bsd_gidset = newcred->cr_groups;
134 		ngrp--;
135 		while (ngrp >= 0) {
136 			bsd_gidset[ngrp + 1] = linux_gidset[ngrp];
137 			ngrp--;
138 		}
139 	}
140 	else
141 		newcred->cr_ngroups = 1;
142 
143 	setsugid(td->td_proc);
144 	p->p_ucred = newcred;
145 	PROC_UNLOCK(p);
146 	crfree(oldcred);
147 	return (0);
148 }
149 
150 int
151 linux_getgroups16(struct thread *td, struct linux_getgroups16_args *args)
152 {
153 	struct ucred *cred;
154 	l_gid16_t linux_gidset[NGROUPS];
155 	gid_t *bsd_gidset;
156 	int bsd_gidsetsz, ngrp, error;
157 
158 #ifdef DEBUG
159 	if (ldebug(getgroups16))
160 		printf(ARGS(getgroups16, "%d, *"), args->gidsetsize);
161 #endif
162 
163 	cred = td->td_ucred;
164 	bsd_gidset = cred->cr_groups;
165 	bsd_gidsetsz = cred->cr_ngroups - 1;
166 
167 	/*
168 	 * cr_groups[0] holds egid. Returning the whole set
169 	 * here will cause a duplicate. Exclude cr_groups[0]
170 	 * to prevent that.
171 	 */
172 
173 	if ((ngrp = args->gidsetsize) == 0) {
174 		td->td_retval[0] = bsd_gidsetsz;
175 		return (0);
176 	}
177 
178 	if (ngrp < bsd_gidsetsz)
179 		return (EINVAL);
180 
181 	ngrp = 0;
182 	while (ngrp < bsd_gidsetsz) {
183 		linux_gidset[ngrp] = bsd_gidset[ngrp + 1];
184 		ngrp++;
185 	}
186 
187 	error = copyout(linux_gidset, (caddr_t)args->gidset,
188 	    ngrp * sizeof(l_gid16_t));
189 	if (error)
190 		return (error);
191 
192 	td->td_retval[0] = ngrp;
193 	return (0);
194 }
195 
196 /*
197  * The FreeBSD native getgid(2) and getuid(2) also modify td->td_retval[1]
198  * when COMPAT_43 or COMPAT_SUNOS is defined. This globbers registers that
199  * are assumed to be preserved. The following lightweight syscalls fixes
200  * this. See also linux_getpid(2), linux_getgid(2) and linux_getuid(2) in
201  * linux_misc.c
202  *
203  * linux_getgid16() - MP SAFE
204  * linux_getuid16() - MP SAFE
205  */
206 
207 int
208 linux_getgid16(struct thread *td, struct linux_getgid16_args *args)
209 {
210 
211 	td->td_retval[0] = td->td_ucred->cr_rgid;
212 	return (0);
213 }
214 
215 int
216 linux_getuid16(struct thread *td, struct linux_getuid16_args *args)
217 {
218 
219 	td->td_retval[0] = td->td_ucred->cr_ruid;
220 	return (0);
221 }
222 
223 int
224 linux_getegid16(struct thread *td, struct linux_getegid16_args *args)
225 {
226 	struct getegid_args bsd;
227 
228 	return (getegid(td, &bsd));
229 }
230 
231 int
232 linux_geteuid16(struct thread *td, struct linux_geteuid16_args *args)
233 {
234 	struct geteuid_args bsd;
235 
236 	return (geteuid(td, &bsd));
237 }
238 
239 int
240 linux_setgid16(struct thread *td, struct linux_setgid16_args *args)
241 {
242 	struct setgid_args bsd;
243 
244 	bsd.gid = args->gid;
245 	return (setgid(td, &bsd));
246 }
247 
248 int
249 linux_setuid16(struct thread *td, struct linux_setuid16_args *args)
250 {
251 	struct setuid_args bsd;
252 
253 	bsd.uid = args->uid;
254 	return (setuid(td, &bsd));
255 }
256 
257 int
258 linux_setregid16(struct thread *td, struct linux_setregid16_args *args)
259 {
260 	struct setregid_args bsd;
261 
262 	bsd.rgid = CAST_NOCHG(args->rgid);
263 	bsd.egid = CAST_NOCHG(args->egid);
264 	return (setregid(td, &bsd));
265 }
266 
267 int
268 linux_setreuid16(struct thread *td, struct linux_setreuid16_args *args)
269 {
270 	struct setreuid_args bsd;
271 
272 	bsd.ruid = CAST_NOCHG(args->ruid);
273 	bsd.euid = CAST_NOCHG(args->euid);
274 	return (setreuid(td, &bsd));
275 }
276 
277 int
278 linux_setresgid16(struct thread *td, struct linux_setresgid16_args *args)
279 {
280 	struct setresgid_args bsd;
281 
282 	bsd.rgid = CAST_NOCHG(args->rgid);
283 	bsd.egid = CAST_NOCHG(args->egid);
284 	bsd.sgid = CAST_NOCHG(args->sgid);
285 	return (setresgid(td, &bsd));
286 }
287 
288 int
289 linux_setresuid16(struct thread *td, struct linux_setresuid16_args *args)
290 {
291 	struct setresuid_args bsd;
292 
293 	bsd.ruid = CAST_NOCHG(args->ruid);
294 	bsd.euid = CAST_NOCHG(args->euid);
295 	bsd.suid = CAST_NOCHG(args->suid);
296 	return (setresuid(td, &bsd));
297 }
298