1 /*
2  * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
3  * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
4  * Copyright (c) 1993-1996 Rick Sladkey <jrs@world.std.com>
5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
6  * Copyright (c) 2003-2016 Dmitry V. Levin <ldv@altlinux.org>
7  * Copyright (c) 2014-2018 The strace developers.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifdef STRACE_UID_SIZE
34 # if STRACE_UID_SIZE != 16
35 #  error invalid STRACE_UID_SIZE
36 # endif
37 
38 # define SIZEIFY(x)		SIZEIFY_(x, STRACE_UID_SIZE)
39 # define SIZEIFY_(x, size)	SIZEIFY__(x, size)
40 # define SIZEIFY__(x, size)	x ## size
41 
42 # define printuid	SIZEIFY(printuid)
43 # define sys_chown	SIZEIFY(sys_chown)
44 # define sys_fchown	SIZEIFY(sys_fchown)
45 # define sys_getgroups	SIZEIFY(sys_getgroups)
46 # define sys_getresuid	SIZEIFY(sys_getresuid)
47 # define sys_getuid	SIZEIFY(sys_getuid)
48 # define sys_setfsuid	SIZEIFY(sys_setfsuid)
49 # define sys_setgroups	SIZEIFY(sys_setgroups)
50 # define sys_setresuid	SIZEIFY(sys_setresuid)
51 # define sys_setreuid	SIZEIFY(sys_setreuid)
52 # define sys_setuid	SIZEIFY(sys_setuid)
53 #endif /* STRACE_UID_SIZE */
54 
55 #include "defs.h"
56 
57 #ifdef STRACE_UID_SIZE
58 # if !HAVE_ARCH_UID16_SYSCALLS
59 #  undef STRACE_UID_SIZE
60 # endif
61 #else
62 # define STRACE_UID_SIZE 32
63 #endif
64 
65 #ifdef STRACE_UID_SIZE
66 
67 # undef uid_t
68 # define uid_t		uid_t_(STRACE_UID_SIZE)
69 # define uid_t_(size)	uid_t__(size)
70 # define uid_t__(size)	uint ## size ## _t
71 
SYS_FUNC(getuid)72 SYS_FUNC(getuid)
73 {
74 	return RVAL_DECODED;
75 }
76 
SYS_FUNC(setfsuid)77 SYS_FUNC(setfsuid)
78 {
79 	printuid("", tcp->u_arg[0]);
80 
81 	return RVAL_DECODED;
82 }
83 
SYS_FUNC(setuid)84 SYS_FUNC(setuid)
85 {
86 	printuid("", tcp->u_arg[0]);
87 
88 	return RVAL_DECODED;
89 }
90 
91 static void
get_print_uid(struct tcb * const tcp,const char * const prefix,const kernel_ulong_t addr)92 get_print_uid(struct tcb *const tcp, const char *const prefix,
93 	      const kernel_ulong_t addr)
94 {
95 	uid_t uid;
96 
97 	tprints(prefix);
98 	if (!umove_or_printaddr(tcp, addr, &uid)) {
99 		printuid("[", uid);
100 		tprints("]");
101 	}
102 }
103 
SYS_FUNC(getresuid)104 SYS_FUNC(getresuid)
105 {
106 	if (entering(tcp))
107 		return 0;
108 
109 	get_print_uid(tcp, "", tcp->u_arg[0]);
110 	get_print_uid(tcp, ", ", tcp->u_arg[1]);
111 	get_print_uid(tcp, ", ", tcp->u_arg[2]);
112 
113 	return 0;
114 }
115 
SYS_FUNC(setreuid)116 SYS_FUNC(setreuid)
117 {
118 	printuid("", tcp->u_arg[0]);
119 	printuid(", ", tcp->u_arg[1]);
120 
121 	return RVAL_DECODED;
122 }
123 
SYS_FUNC(setresuid)124 SYS_FUNC(setresuid)
125 {
126 	printuid("", tcp->u_arg[0]);
127 	printuid(", ", tcp->u_arg[1]);
128 	printuid(", ", tcp->u_arg[2]);
129 
130 	return RVAL_DECODED;
131 }
132 
SYS_FUNC(chown)133 SYS_FUNC(chown)
134 {
135 	printpath(tcp, tcp->u_arg[0]);
136 	printuid(", ", tcp->u_arg[1]);
137 	printuid(", ", tcp->u_arg[2]);
138 
139 	return RVAL_DECODED;
140 }
141 
SYS_FUNC(fchown)142 SYS_FUNC(fchown)
143 {
144 	printfd(tcp, tcp->u_arg[0]);
145 	printuid(", ", tcp->u_arg[1]);
146 	printuid(", ", tcp->u_arg[2]);
147 
148 	return RVAL_DECODED;
149 }
150 
151 void
printuid(const char * text,const unsigned int uid)152 printuid(const char *text, const unsigned int uid)
153 {
154 	if ((uid_t) -1U == (uid_t) uid)
155 		tprintf("%s-1", text);
156 	else
157 		tprintf("%s%u", text, (uid_t) uid);
158 }
159 
160 static bool
print_gid(struct tcb * tcp,void * elem_buf,size_t elem_size,void * data)161 print_gid(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
162 {
163 	printuid("", (*(uid_t *) elem_buf));
164 
165 	return true;
166 }
167 
168 static void
print_groups(struct tcb * const tcp,const unsigned int len,const kernel_ulong_t addr)169 print_groups(struct tcb *const tcp, const unsigned int len,
170 	     const kernel_ulong_t addr)
171 {
172 	static unsigned long ngroups_max;
173 	if (!ngroups_max)
174 		ngroups_max = sysconf(_SC_NGROUPS_MAX);
175 
176 	if (len > ngroups_max) {
177 		printaddr(addr);
178 		return;
179 	}
180 
181 	uid_t gid;
182 	print_array(tcp, addr, len, &gid, sizeof(gid),
183 		    tfetch_mem, print_gid, 0);
184 }
185 
SYS_FUNC(setgroups)186 SYS_FUNC(setgroups)
187 {
188 	const int len = tcp->u_arg[0];
189 
190 	tprintf("%d, ", len);
191 	print_groups(tcp, len, tcp->u_arg[1]);
192 	return RVAL_DECODED;
193 }
194 
SYS_FUNC(getgroups)195 SYS_FUNC(getgroups)
196 {
197 	if (entering(tcp))
198 		tprintf("%d, ", (int) tcp->u_arg[0]);
199 	else
200 		print_groups(tcp, tcp->u_rval, tcp->u_arg[1]);
201 	return 0;
202 }
203 
204 #endif /* STRACE_UID_SIZE */
205