xref: /freebsd/sys/compat/linux/linux_uid16.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001  The FreeBSD Project
5  * 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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/fcntl.h>
31 #include <sys/lock.h>
32 #include <sys/malloc.h>
33 #include <sys/mutex.h>
34 #include <sys/priv.h>
35 #include <sys/proc.h>
36 #include <sys/syscallsubr.h>
37 #include <sys/sysproto.h>
38 
39 #ifdef COMPAT_LINUX32
40 #include <machine/../linux32/linux.h>
41 #include <machine/../linux32/linux32_proto.h>
42 #else
43 #include <machine/../linux/linux.h>
44 #include <machine/../linux/linux_proto.h>
45 #endif
46 
47 #include <compat/linux/linux_dtrace.h>
48 #include <compat/linux/linux_util.h>
49 
50 /* DTrace init */
51 LIN_SDT_PROVIDER_DECLARE(LINUX_DTRACE);
52 
53 /**
54  * DTrace probes in this module.
55  */
56 LIN_SDT_PROBE_DEFINE1(uid16, linux_chown16, conv_path, "char *");
57 LIN_SDT_PROBE_DEFINE1(uid16, linux_lchown16, conv_path, "char *");
58 LIN_SDT_PROBE_DEFINE1(uid16, linux_setgroups16, copyin_error, "int");
59 LIN_SDT_PROBE_DEFINE1(uid16, linux_setgroups16, priv_check_cred_error, "int");
60 LIN_SDT_PROBE_DEFINE1(uid16, linux_getgroups16, copyout_error, "int");
61 
62 DUMMY(setfsuid16);
63 DUMMY(setfsgid16);
64 DUMMY(getresuid16);
65 DUMMY(getresgid16);
66 
67 #define	CAST_NOCHG(x)	((x == 0xFFFF) ? -1 : x)
68 
69 int
70 linux_chown16(struct thread *td, struct linux_chown16_args *args)
71 {
72 
73 	return (kern_fchownat(td, AT_FDCWD, args->path, UIO_USERSPACE,
74 	    CAST_NOCHG(args->uid), CAST_NOCHG(args->gid), 0));
75 }
76 
77 int
78 linux_lchown16(struct thread *td, struct linux_lchown16_args *args)
79 {
80 
81 	return (kern_fchownat(td, AT_FDCWD, args->path, UIO_USERSPACE,
82 	    CAST_NOCHG(args->uid), CAST_NOCHG(args->gid), AT_SYMLINK_NOFOLLOW));
83 }
84 
85 int
86 linux_setgroups16(struct thread *td, struct linux_setgroups16_args *args)
87 {
88 	struct ucred *newcred, *oldcred;
89 	l_gid16_t *linux_gidset;
90 	gid_t *bsd_gidset;
91 	int ngrp, error;
92 	struct proc *p;
93 
94 	ngrp = args->gidsetsize;
95 	if (ngrp < 0 || ngrp >= ngroups_max + 1)
96 		return (EINVAL);
97 	linux_gidset = malloc(ngrp * sizeof(*linux_gidset), M_LINUX, M_WAITOK);
98 	error = copyin(args->gidset, linux_gidset, ngrp * sizeof(l_gid16_t));
99 	if (error) {
100 		LIN_SDT_PROBE1(uid16, linux_setgroups16, copyin_error, error);
101 		free(linux_gidset, M_LINUX);
102 		return (error);
103 	}
104 	newcred = crget();
105 	p = td->td_proc;
106 	PROC_LOCK(p);
107 	oldcred = crcopysafe(p, newcred);
108 
109 	/*
110 	 * cr_groups[0] holds egid. Setting the whole set from
111 	 * the supplied set will cause egid to be changed too.
112 	 * Keep cr_groups[0] unchanged to prevent that.
113 	 */
114 
115 	if ((error = priv_check_cred(oldcred, PRIV_CRED_SETGROUPS)) != 0) {
116 		PROC_UNLOCK(p);
117 		crfree(newcred);
118 
119 		LIN_SDT_PROBE1(uid16, linux_setgroups16, priv_check_cred_error,
120 		    error);
121 		goto out;
122 	}
123 
124 	if (ngrp > 0) {
125 		newcred->cr_ngroups = ngrp + 1;
126 
127 		bsd_gidset = newcred->cr_groups;
128 		ngrp--;
129 		while (ngrp >= 0) {
130 			bsd_gidset[ngrp + 1] = linux_gidset[ngrp];
131 			ngrp--;
132 		}
133 	}
134 	else
135 		newcred->cr_ngroups = 1;
136 
137 	setsugid(td->td_proc);
138 	proc_set_cred(p, newcred);
139 	PROC_UNLOCK(p);
140 	crfree(oldcred);
141 	error = 0;
142 out:
143 	free(linux_gidset, M_LINUX);
144 
145 	return (error);
146 }
147 
148 int
149 linux_getgroups16(struct thread *td, struct linux_getgroups16_args *args)
150 {
151 	struct ucred *cred;
152 	l_gid16_t *linux_gidset;
153 	gid_t *bsd_gidset;
154 	int bsd_gidsetsz, ngrp, error;
155 
156 	cred = td->td_ucred;
157 	bsd_gidset = cred->cr_groups;
158 	bsd_gidsetsz = cred->cr_ngroups - 1;
159 
160 	/*
161 	 * cr_groups[0] holds egid. Returning the whole set
162 	 * here will cause a duplicate. Exclude cr_groups[0]
163 	 * to prevent that.
164 	 */
165 
166 	if ((ngrp = args->gidsetsize) == 0) {
167 		td->td_retval[0] = bsd_gidsetsz;
168 		return (0);
169 	}
170 
171 	if (ngrp < bsd_gidsetsz)
172 		return (EINVAL);
173 
174 	ngrp = 0;
175 	linux_gidset = malloc(bsd_gidsetsz * sizeof(*linux_gidset),
176 	    M_LINUX, M_WAITOK);
177 	while (ngrp < bsd_gidsetsz) {
178 		linux_gidset[ngrp] = bsd_gidset[ngrp + 1];
179 		ngrp++;
180 	}
181 
182 	error = copyout(linux_gidset, args->gidset, ngrp * sizeof(l_gid16_t));
183 	free(linux_gidset, M_LINUX);
184 	if (error) {
185 		LIN_SDT_PROBE1(uid16, linux_getgroups16, copyout_error, error);
186 		return (error);
187 	}
188 
189 	td->td_retval[0] = ngrp;
190 
191 	return (0);
192 }
193 
194 int
195 linux_getgid16(struct thread *td, struct linux_getgid16_args *args)
196 {
197 
198 	td->td_retval[0] = td->td_ucred->cr_rgid;
199 
200 	return (0);
201 }
202 
203 int
204 linux_getuid16(struct thread *td, struct linux_getuid16_args *args)
205 {
206 
207 	td->td_retval[0] = td->td_ucred->cr_ruid;
208 
209 	return (0);
210 }
211 
212 int
213 linux_getegid16(struct thread *td, struct linux_getegid16_args *args)
214 {
215 	struct getegid_args bsd;
216 	int error;
217 
218 	error = sys_getegid(td, &bsd);
219 
220 	return (error);
221 }
222 
223 int
224 linux_geteuid16(struct thread *td, struct linux_geteuid16_args *args)
225 {
226 	struct geteuid_args bsd;
227 	int error;
228 
229 	error = sys_geteuid(td, &bsd);
230 
231 	return (error);
232 }
233 
234 int
235 linux_setgid16(struct thread *td, struct linux_setgid16_args *args)
236 {
237 	struct setgid_args bsd;
238 	int error;
239 
240 	bsd.gid = args->gid;
241 	error = sys_setgid(td, &bsd);
242 
243 	return (error);
244 }
245 
246 int
247 linux_setuid16(struct thread *td, struct linux_setuid16_args *args)
248 {
249 	struct setuid_args bsd;
250 	int error;
251 
252 	bsd.uid = args->uid;
253 	error = sys_setuid(td, &bsd);
254 
255 	return (error);
256 }
257 
258 int
259 linux_setregid16(struct thread *td, struct linux_setregid16_args *args)
260 {
261 	struct setregid_args bsd;
262 	int error;
263 
264 	bsd.rgid = CAST_NOCHG(args->rgid);
265 	bsd.egid = CAST_NOCHG(args->egid);
266 	error = sys_setregid(td, &bsd);
267 
268 	return (error);
269 }
270 
271 int
272 linux_setreuid16(struct thread *td, struct linux_setreuid16_args *args)
273 {
274 	struct setreuid_args bsd;
275 	int error;
276 
277 	bsd.ruid = CAST_NOCHG(args->ruid);
278 	bsd.euid = CAST_NOCHG(args->euid);
279 	error = sys_setreuid(td, &bsd);
280 
281 	return (error);
282 }
283 
284 int
285 linux_setresgid16(struct thread *td, struct linux_setresgid16_args *args)
286 {
287 	struct setresgid_args bsd;
288 	int error;
289 
290 	bsd.rgid = CAST_NOCHG(args->rgid);
291 	bsd.egid = CAST_NOCHG(args->egid);
292 	bsd.sgid = CAST_NOCHG(args->sgid);
293 	error = sys_setresgid(td, &bsd);
294 
295 	return (error);
296 }
297 
298 int
299 linux_setresuid16(struct thread *td, struct linux_setresuid16_args *args)
300 {
301 	struct setresuid_args bsd;
302 	int error;
303 
304 	bsd.ruid = CAST_NOCHG(args->ruid);
305 	bsd.euid = CAST_NOCHG(args->euid);
306 	bsd.suid = CAST_NOCHG(args->suid);
307 	error = sys_setresuid(td, &bsd);
308 
309 	return (error);
310 }
311