xref: /freebsd/sys/compat/linux/linux_uid16.c (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
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 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/lock.h>
32 #include <sys/malloc.h>
33 #include <sys/mutex.h>
34 #include <sys/proc.h>
35 #include <sys/syscallsubr.h>
36 #include <sys/sysproto.h>
37 #include <sys/systm.h>
38 
39 #include "opt_compat.h"
40 
41 #ifdef COMPAT_LINUX32
42 #include <machine/../linux32/linux.h>
43 #include <machine/../linux32/linux32_proto.h>
44 #else
45 #include <machine/../linux/linux.h>
46 #include <machine/../linux/linux_proto.h>
47 #endif
48 
49 #include <compat/linux/linux_util.h>
50 
51 DUMMY(setfsuid16);
52 DUMMY(setfsgid16);
53 DUMMY(getresuid16);
54 DUMMY(getresgid16);
55 
56 #define	CAST_NOCHG(x)	((x == 0xFFFF) ? -1 : x)
57 
58 int
59 linux_chown16(struct thread *td, struct linux_chown16_args *args)
60 {
61 	char *path;
62 	int error;
63 
64 	LCONVPATHEXIST(td, args->path, &path);
65 
66 #ifdef DEBUG
67 	if (ldebug(chown16))
68 		printf(ARGS(chown16, "%s, %d, %d"), path, args->uid, args->gid);
69 #endif
70 	error = kern_chown(td, path, UIO_SYSSPACE, CAST_NOCHG(args->uid),
71 	    CAST_NOCHG(args->gid));
72 	LFREEPATH(path);
73 	return (error);
74 }
75 
76 int
77 linux_lchown16(struct thread *td, struct linux_lchown16_args *args)
78 {
79 	char *path;
80 	int error;
81 
82 	LCONVPATHEXIST(td, args->path, &path);
83 
84 #ifdef DEBUG
85 	if (ldebug(lchown16))
86 		printf(ARGS(lchown16, "%s, %d, %d"), path, args->uid,
87 		    args->gid);
88 #endif
89 	error = kern_lchown(td, path, UIO_SYSSPACE, CAST_NOCHG(args->uid),
90 	    CAST_NOCHG(args->gid));
91 	LFREEPATH(path);
92 	return (error);
93 }
94 
95 int
96 linux_setgroups16(struct thread *td, struct linux_setgroups16_args *args)
97 {
98 	struct ucred *newcred, *oldcred;
99 	l_gid16_t linux_gidset[NGROUPS];
100 	gid_t *bsd_gidset;
101 	int ngrp, error;
102 	struct proc *p;
103 
104 #ifdef DEBUG
105 	if (ldebug(setgroups16))
106 		printf(ARGS(setgroups16, "%d, *"), args->gidsetsize);
107 #endif
108 
109 	ngrp = args->gidsetsize;
110 	if (ngrp < 0 || ngrp >= NGROUPS)
111 		return (EINVAL);
112 	error = copyin(args->gidset, linux_gidset, ngrp * sizeof(l_gid16_t));
113 	if (error)
114 		return (error);
115 	newcred = crget();
116 	p = td->td_proc;
117 	PROC_LOCK(p);
118 	oldcred = p->p_ucred;
119 
120 	/*
121 	 * cr_groups[0] holds egid. Setting the whole set from
122 	 * the supplied set will cause egid to be changed too.
123 	 * Keep cr_groups[0] unchanged to prevent that.
124 	 */
125 
126 	if ((error = suser_cred(oldcred, SUSER_ALLOWJAIL)) != 0) {
127 		PROC_UNLOCK(p);
128 		crfree(newcred);
129 		return (error);
130 	}
131 
132 	crcopy(newcred, oldcred);
133 	if (ngrp > 0) {
134 		newcred->cr_ngroups = ngrp + 1;
135 
136 		bsd_gidset = newcred->cr_groups;
137 		ngrp--;
138 		while (ngrp >= 0) {
139 			bsd_gidset[ngrp + 1] = linux_gidset[ngrp];
140 			ngrp--;
141 		}
142 	}
143 	else
144 		newcred->cr_ngroups = 1;
145 
146 	setsugid(td->td_proc);
147 	p->p_ucred = newcred;
148 	PROC_UNLOCK(p);
149 	crfree(oldcred);
150 	return (0);
151 }
152 
153 int
154 linux_getgroups16(struct thread *td, struct linux_getgroups16_args *args)
155 {
156 	struct ucred *cred;
157 	l_gid16_t linux_gidset[NGROUPS];
158 	gid_t *bsd_gidset;
159 	int bsd_gidsetsz, ngrp, error;
160 
161 #ifdef DEBUG
162 	if (ldebug(getgroups16))
163 		printf(ARGS(getgroups16, "%d, *"), args->gidsetsize);
164 #endif
165 
166 	cred = td->td_ucred;
167 	bsd_gidset = cred->cr_groups;
168 	bsd_gidsetsz = cred->cr_ngroups - 1;
169 
170 	/*
171 	 * cr_groups[0] holds egid. Returning the whole set
172 	 * here will cause a duplicate. Exclude cr_groups[0]
173 	 * to prevent that.
174 	 */
175 
176 	if ((ngrp = args->gidsetsize) == 0) {
177 		td->td_retval[0] = bsd_gidsetsz;
178 		return (0);
179 	}
180 
181 	if (ngrp < bsd_gidsetsz)
182 		return (EINVAL);
183 
184 	ngrp = 0;
185 	while (ngrp < bsd_gidsetsz) {
186 		linux_gidset[ngrp] = bsd_gidset[ngrp + 1];
187 		ngrp++;
188 	}
189 
190 	error = copyout(linux_gidset, args->gidset, ngrp * sizeof(l_gid16_t));
191 	if (error)
192 		return (error);
193 
194 	td->td_retval[0] = ngrp;
195 	return (0);
196 }
197 
198 /*
199  * The FreeBSD native getgid(2) and getuid(2) also modify td->td_retval[1]
200  * when COMPAT_43 is defined. This globbers registers that
201  * are assumed to be preserved. The following lightweight syscalls fixes
202  * this. See also linux_getpid(2), linux_getgid(2) and linux_getuid(2) in
203  * linux_misc.c
204  *
205  * linux_getgid16() - MP SAFE
206  * linux_getuid16() - MP SAFE
207  */
208 
209 int
210 linux_getgid16(struct thread *td, struct linux_getgid16_args *args)
211 {
212 
213 	td->td_retval[0] = td->td_ucred->cr_rgid;
214 	return (0);
215 }
216 
217 int
218 linux_getuid16(struct thread *td, struct linux_getuid16_args *args)
219 {
220 
221 	td->td_retval[0] = td->td_ucred->cr_ruid;
222 	return (0);
223 }
224 
225 int
226 linux_getegid16(struct thread *td, struct linux_getegid16_args *args)
227 {
228 	struct getegid_args bsd;
229 
230 	return (getegid(td, &bsd));
231 }
232 
233 int
234 linux_geteuid16(struct thread *td, struct linux_geteuid16_args *args)
235 {
236 	struct geteuid_args bsd;
237 
238 	return (geteuid(td, &bsd));
239 }
240 
241 int
242 linux_setgid16(struct thread *td, struct linux_setgid16_args *args)
243 {
244 	struct setgid_args bsd;
245 
246 	bsd.gid = args->gid;
247 	return (setgid(td, &bsd));
248 }
249 
250 int
251 linux_setuid16(struct thread *td, struct linux_setuid16_args *args)
252 {
253 	struct setuid_args bsd;
254 
255 	bsd.uid = args->uid;
256 	return (setuid(td, &bsd));
257 }
258 
259 int
260 linux_setregid16(struct thread *td, struct linux_setregid16_args *args)
261 {
262 	struct setregid_args bsd;
263 
264 	bsd.rgid = CAST_NOCHG(args->rgid);
265 	bsd.egid = CAST_NOCHG(args->egid);
266 	return (setregid(td, &bsd));
267 }
268 
269 int
270 linux_setreuid16(struct thread *td, struct linux_setreuid16_args *args)
271 {
272 	struct setreuid_args bsd;
273 
274 	bsd.ruid = CAST_NOCHG(args->ruid);
275 	bsd.euid = CAST_NOCHG(args->euid);
276 	return (setreuid(td, &bsd));
277 }
278 
279 int
280 linux_setresgid16(struct thread *td, struct linux_setresgid16_args *args)
281 {
282 	struct setresgid_args bsd;
283 
284 	bsd.rgid = CAST_NOCHG(args->rgid);
285 	bsd.egid = CAST_NOCHG(args->egid);
286 	bsd.sgid = CAST_NOCHG(args->sgid);
287 	return (setresgid(td, &bsd));
288 }
289 
290 int
291 linux_setresuid16(struct thread *td, struct linux_setresuid16_args *args)
292 {
293 	struct setresuid_args bsd;
294 
295 	bsd.ruid = CAST_NOCHG(args->ruid);
296 	bsd.euid = CAST_NOCHG(args->euid);
297 	bsd.suid = CAST_NOCHG(args->suid);
298 	return (setresuid(td, &bsd));
299 }
300