xref: /freebsd/sys/compat/linux/linux_uid16.c (revision 031beb4e239bfce798af17f5fe8dba8bcaf13d99)
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/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/fcntl.h>
32 #include <sys/lock.h>
33 #include <sys/malloc.h>
34 #include <sys/mutex.h>
35 #include <sys/priv.h>
36 #include <sys/proc.h>
37 #include <sys/syscallsubr.h>
38 #include <sys/sysproto.h>
39 
40 #ifdef COMPAT_LINUX32
41 #include <machine/../linux32/linux.h>
42 #include <machine/../linux32/linux32_proto.h>
43 #else
44 #include <machine/../linux/linux.h>
45 #include <machine/../linux/linux_proto.h>
46 #endif
47 
48 #include <compat/linux/linux_dtrace.h>
49 #include <compat/linux/linux_util.h>
50 
51 /* DTrace init */
52 LIN_SDT_PROVIDER_DECLARE(LINUX_DTRACE);
53 
54 /**
55  * DTrace probes in this module.
56  */
57 LIN_SDT_PROBE_DEFINE1(uid16, linux_chown16, conv_path, "char *");
58 LIN_SDT_PROBE_DEFINE1(uid16, linux_lchown16, conv_path, "char *");
59 LIN_SDT_PROBE_DEFINE1(uid16, linux_setgroups16, copyin_error, "int");
60 LIN_SDT_PROBE_DEFINE1(uid16, linux_setgroups16, priv_check_cred_error, "int");
61 LIN_SDT_PROBE_DEFINE1(uid16, linux_getgroups16, copyout_error, "int");
62 
63 DUMMY(setfsuid16);
64 DUMMY(setfsgid16);
65 DUMMY(getresuid16);
66 DUMMY(getresgid16);
67 
68 #define	CAST_NOCHG(x)	((x == 0xFFFF) ? -1 : x)
69 
70 int
71 linux_chown16(struct thread *td, struct linux_chown16_args *args)
72 {
73 
74 	return (kern_fchownat(td, AT_FDCWD, args->path, UIO_USERSPACE,
75 	    CAST_NOCHG(args->uid), CAST_NOCHG(args->gid), 0));
76 }
77 
78 int
79 linux_lchown16(struct thread *td, struct linux_lchown16_args *args)
80 {
81 
82 	return (kern_fchownat(td, AT_FDCWD, args->path, UIO_USERSPACE,
83 	    CAST_NOCHG(args->uid), CAST_NOCHG(args->gid), AT_SYMLINK_NOFOLLOW));
84 }
85 
86 int
87 linux_setgroups16(struct thread *td, struct linux_setgroups16_args *args)
88 {
89 	struct ucred *newcred, *oldcred;
90 	l_gid16_t *linux_gidset;
91 	gid_t *bsd_gidset;
92 	int ngrp, error;
93 	struct proc *p;
94 
95 	ngrp = args->gidsetsize;
96 	if (ngrp < 0 || ngrp >= ngroups_max + 1)
97 		return (EINVAL);
98 	linux_gidset = malloc(ngrp * sizeof(*linux_gidset), M_LINUX, M_WAITOK);
99 	error = copyin(args->gidset, linux_gidset, ngrp * sizeof(l_gid16_t));
100 	if (error) {
101 		LIN_SDT_PROBE1(uid16, linux_setgroups16, copyin_error, error);
102 		free(linux_gidset, M_LINUX);
103 		return (error);
104 	}
105 	newcred = crget();
106 	p = td->td_proc;
107 	PROC_LOCK(p);
108 	oldcred = crcopysafe(p, newcred);
109 
110 	/*
111 	 * cr_groups[0] holds egid. Setting the whole set from
112 	 * the supplied set will cause egid to be changed too.
113 	 * Keep cr_groups[0] unchanged to prevent that.
114 	 */
115 
116 	if ((error = priv_check_cred(oldcred, PRIV_CRED_SETGROUPS)) != 0) {
117 		PROC_UNLOCK(p);
118 		crfree(newcred);
119 
120 		LIN_SDT_PROBE1(uid16, linux_setgroups16, priv_check_cred_error,
121 		    error);
122 		goto out;
123 	}
124 
125 	if (ngrp > 0) {
126 		newcred->cr_ngroups = ngrp + 1;
127 
128 		bsd_gidset = newcred->cr_groups;
129 		ngrp--;
130 		while (ngrp >= 0) {
131 			bsd_gidset[ngrp + 1] = linux_gidset[ngrp];
132 			ngrp--;
133 		}
134 	}
135 	else
136 		newcred->cr_ngroups = 1;
137 
138 	setsugid(td->td_proc);
139 	proc_set_cred(p, newcred);
140 	PROC_UNLOCK(p);
141 	crfree(oldcred);
142 	error = 0;
143 out:
144 	free(linux_gidset, M_LINUX);
145 
146 	return (error);
147 }
148 
149 int
150 linux_getgroups16(struct thread *td, struct linux_getgroups16_args *args)
151 {
152 	struct ucred *cred;
153 	l_gid16_t *linux_gidset;
154 	gid_t *bsd_gidset;
155 	int bsd_gidsetsz, ngrp, error;
156 
157 	cred = td->td_ucred;
158 	bsd_gidset = cred->cr_groups;
159 	bsd_gidsetsz = cred->cr_ngroups - 1;
160 
161 	/*
162 	 * cr_groups[0] holds egid. Returning the whole set
163 	 * here will cause a duplicate. Exclude cr_groups[0]
164 	 * to prevent that.
165 	 */
166 
167 	if ((ngrp = args->gidsetsize) == 0) {
168 		td->td_retval[0] = bsd_gidsetsz;
169 		return (0);
170 	}
171 
172 	if (ngrp < bsd_gidsetsz)
173 		return (EINVAL);
174 
175 	ngrp = 0;
176 	linux_gidset = malloc(bsd_gidsetsz * sizeof(*linux_gidset),
177 	    M_LINUX, M_WAITOK);
178 	while (ngrp < bsd_gidsetsz) {
179 		linux_gidset[ngrp] = bsd_gidset[ngrp + 1];
180 		ngrp++;
181 	}
182 
183 	error = copyout(linux_gidset, args->gidset, ngrp * sizeof(l_gid16_t));
184 	free(linux_gidset, M_LINUX);
185 	if (error) {
186 		LIN_SDT_PROBE1(uid16, linux_getgroups16, copyout_error, error);
187 		return (error);
188 	}
189 
190 	td->td_retval[0] = ngrp;
191 
192 	return (0);
193 }
194 
195 int
196 linux_getgid16(struct thread *td, struct linux_getgid16_args *args)
197 {
198 
199 	td->td_retval[0] = td->td_ucred->cr_rgid;
200 
201 	return (0);
202 }
203 
204 int
205 linux_getuid16(struct thread *td, struct linux_getuid16_args *args)
206 {
207 
208 	td->td_retval[0] = td->td_ucred->cr_ruid;
209 
210 	return (0);
211 }
212 
213 int
214 linux_getegid16(struct thread *td, struct linux_getegid16_args *args)
215 {
216 	struct getegid_args bsd;
217 	int error;
218 
219 	error = sys_getegid(td, &bsd);
220 
221 	return (error);
222 }
223 
224 int
225 linux_geteuid16(struct thread *td, struct linux_geteuid16_args *args)
226 {
227 	struct geteuid_args bsd;
228 	int error;
229 
230 	error = sys_geteuid(td, &bsd);
231 
232 	return (error);
233 }
234 
235 int
236 linux_setgid16(struct thread *td, struct linux_setgid16_args *args)
237 {
238 	struct setgid_args bsd;
239 	int error;
240 
241 	bsd.gid = args->gid;
242 	error = sys_setgid(td, &bsd);
243 
244 	return (error);
245 }
246 
247 int
248 linux_setuid16(struct thread *td, struct linux_setuid16_args *args)
249 {
250 	struct setuid_args bsd;
251 	int error;
252 
253 	bsd.uid = args->uid;
254 	error = sys_setuid(td, &bsd);
255 
256 	return (error);
257 }
258 
259 int
260 linux_setregid16(struct thread *td, struct linux_setregid16_args *args)
261 {
262 	struct setregid_args bsd;
263 	int error;
264 
265 	bsd.rgid = CAST_NOCHG(args->rgid);
266 	bsd.egid = CAST_NOCHG(args->egid);
267 	error = sys_setregid(td, &bsd);
268 
269 	return (error);
270 }
271 
272 int
273 linux_setreuid16(struct thread *td, struct linux_setreuid16_args *args)
274 {
275 	struct setreuid_args bsd;
276 	int error;
277 
278 	bsd.ruid = CAST_NOCHG(args->ruid);
279 	bsd.euid = CAST_NOCHG(args->euid);
280 	error = sys_setreuid(td, &bsd);
281 
282 	return (error);
283 }
284 
285 int
286 linux_setresgid16(struct thread *td, struct linux_setresgid16_args *args)
287 {
288 	struct setresgid_args bsd;
289 	int error;
290 
291 	bsd.rgid = CAST_NOCHG(args->rgid);
292 	bsd.egid = CAST_NOCHG(args->egid);
293 	bsd.sgid = CAST_NOCHG(args->sgid);
294 	error = sys_setresgid(td, &bsd);
295 
296 	return (error);
297 }
298 
299 int
300 linux_setresuid16(struct thread *td, struct linux_setresuid16_args *args)
301 {
302 	struct setresuid_args bsd;
303 	int error;
304 
305 	bsd.ruid = CAST_NOCHG(args->ruid);
306 	bsd.euid = CAST_NOCHG(args->euid);
307 	bsd.suid = CAST_NOCHG(args->suid);
308 	error = sys_setresuid(td, &bsd);
309 
310 	return (error);
311 }
312