1 /*
2  * Copyright (c) 2000 Wichert Akkerman <wakkerma@debian.org>
3  * Copyright (c) 2011 Denys Vlasenko <dvlasenk@redhat.com>
4  * Copyright (c) 2005-2015 Dmitry V. Levin <ldv@altlinux.org>
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  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include "defs.h"
31 
32 /* these constants are the same as in <linux/capability.h> */
33 enum {
34 #include "caps0.h"
35 };
36 
37 #include "xlat/cap_mask0.h"
38 
39 /* these constants are CAP_TO_INDEX'ed constants from <linux/capability.h> */
40 enum {
41 #include "caps1.h"
42 };
43 
44 #include "xlat/cap_mask1.h"
45 
46 /* these constants are the same as in <linux/capability.h> */
47 enum {
48 	_LINUX_CAPABILITY_VERSION_1 = 0x19980330,
49 	_LINUX_CAPABILITY_VERSION_2 = 0x20071026,
50 	_LINUX_CAPABILITY_VERSION_3 = 0x20080522
51 };
52 
53 #include "xlat/cap_version.h"
54 
55 typedef struct user_cap_header_struct {
56 	uint32_t version;
57 	int pid;
58 } *cap_user_header_t;
59 
60 typedef struct user_cap_data_struct {
61 	uint32_t effective;
62 	uint32_t permitted;
63 	uint32_t inheritable;
64 } *cap_user_data_t;
65 
66 static cap_user_header_t
get_cap_header(struct tcb * tcp,unsigned long addr)67 get_cap_header(struct tcb *tcp, unsigned long addr)
68 {
69 	static struct user_cap_header_struct header;
70 
71 	if (!addr || !verbose(tcp))
72 		return NULL;
73 
74 	if (umove(tcp, addr, &header) < 0)
75 		return NULL;
76 
77 	return &header;
78 }
79 
80 static void
print_cap_header(struct tcb * tcp,unsigned long addr,cap_user_header_t h)81 print_cap_header(struct tcb *tcp, unsigned long addr, cap_user_header_t h)
82 {
83 	if (!addr || !h) {
84 		printaddr(addr);
85 		return;
86 	}
87 
88 	tprints("{");
89 	printxval(cap_version, h->version,
90 		  "_LINUX_CAPABILITY_VERSION_???");
91 	tprintf(", %d}", h->pid);
92 }
93 
94 static void
print_cap_bits(const uint32_t lo,const uint32_t hi)95 print_cap_bits(const uint32_t lo, const uint32_t hi)
96 {
97 	if (lo || !hi)
98 		printflags(cap_mask0, lo, "CAP_???");
99 
100 	if (hi) {
101 		if (lo)
102 			tprints("|");
103 		printflags(cap_mask1, hi, "CAP_???");
104 	}
105 }
106 
107 static void
print_cap_data(struct tcb * tcp,unsigned long addr,const cap_user_header_t h)108 print_cap_data(struct tcb *tcp, unsigned long addr, const cap_user_header_t h)
109 {
110 	struct user_cap_data_struct data[2];
111 	unsigned int len;
112 
113 	if (!addr || !h) {
114 		printaddr(addr);
115 		return;
116 	}
117 
118 	if (_LINUX_CAPABILITY_VERSION_2 == h->version ||
119 	    _LINUX_CAPABILITY_VERSION_3 == h->version)
120 		len = 2;
121 	else
122 		len = 1;
123 
124 	if (umoven_or_printaddr(tcp, addr, len * sizeof(data[0]), data))
125 		return;
126 
127 	tprints("{");
128 	print_cap_bits(data[0].effective, len > 1 ? data[1].effective : 0);
129 	tprints(", ");
130 	print_cap_bits(data[0].permitted, len > 1 ? data[1].permitted : 0);
131 	tprints(", ");
132 	print_cap_bits(data[0].inheritable, len > 1 ? data[1].inheritable : 0);
133 	tprints("}");
134 }
135 
SYS_FUNC(capget)136 SYS_FUNC(capget)
137 {
138 	cap_user_header_t h;
139 
140 	if (entering(tcp)) {
141 		h = get_cap_header(tcp, tcp->u_arg[0]);
142 		print_cap_header(tcp, tcp->u_arg[0], h);
143 		tprints(", ");
144 	} else {
145 		h = syserror(tcp) ? NULL : get_cap_header(tcp, tcp->u_arg[0]);
146 		print_cap_data(tcp, tcp->u_arg[1], h);
147 	}
148 	return 0;
149 }
150 
SYS_FUNC(capset)151 SYS_FUNC(capset)
152 {
153 	cap_user_header_t h = get_cap_header(tcp, tcp->u_arg[0]);
154 	print_cap_header(tcp, tcp->u_arg[0], h);
155 	tprints(", ");
156 	print_cap_data(tcp, tcp->u_arg[1], h);
157 
158 	return RVAL_DECODED;
159 }
160