1 /*
2  * Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
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  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "defs.h"
29 
30 #ifndef MAX_HANDLE_SZ
31 # define MAX_HANDLE_SZ 128
32 #endif
33 
34 typedef struct {
35 	unsigned int handle_bytes;
36 	int handle_type;
37 } file_handle_header;
38 
SYS_FUNC(name_to_handle_at)39 SYS_FUNC(name_to_handle_at)
40 {
41 	file_handle_header h;
42 	const long addr = tcp->u_arg[2];
43 
44 	if (entering(tcp)) {
45 		/* dirfd */
46 		print_dirfd(tcp, tcp->u_arg[0]);
47 
48 		/* pathname */
49 		printpath(tcp, tcp->u_arg[1]);
50 		tprints(", ");
51 
52 		/* handle */
53 		if (umove_or_printaddr(tcp, addr, &h)) {
54 			tprints(", ");
55 
56 			/* mount_id */
57 			printaddr(tcp->u_arg[3]);
58 			tprints(", ");
59 
60 			/* flags */
61 			printflags(at_flags, tcp->u_arg[4], "AT_???");
62 
63 			return RVAL_DECODED;
64 		}
65 		tprintf("{handle_bytes=%u", h.handle_bytes);
66 
67 		/*
68 		 * Abusing tcp->auxstr as a temporary storage.
69 		 * Will be used and cleared on syscall exit.
70 		 */
71 		tcp->auxstr = (void *) (unsigned long) h.handle_bytes;
72 
73 		return 0;
74 	} else {
75 		unsigned int i = (unsigned long) tcp->auxstr;
76 
77 		if ((!syserror(tcp) || EOVERFLOW == tcp->u_error)
78 		    && !umove(tcp, addr, &h)) {
79 			unsigned char f_handle[MAX_HANDLE_SZ];
80 
81 			if (i != h.handle_bytes)
82 				tprintf(" => %u", h.handle_bytes);
83 			if (!syserror(tcp)) {
84 				tprintf(", handle_type=%d", h.handle_type);
85 				if (h.handle_bytes > MAX_HANDLE_SZ)
86 					h.handle_bytes = MAX_HANDLE_SZ;
87 				if (!umoven(tcp, addr + sizeof(h), h.handle_bytes,
88 					    f_handle)) {
89 					tprints(", f_handle=0x");
90 					for (i = 0; i < h.handle_bytes; ++i)
91 						tprintf("%02x", f_handle[i]);
92 				}
93 			}
94 		}
95 		tprints("}, ");
96 		tcp->auxstr = NULL;
97 
98 		/* mount_id */
99 		printnum_int(tcp, tcp->u_arg[3], "%d");
100 		tprints(", ");
101 
102 		/* flags */
103 		printflags(at_flags, tcp->u_arg[4], "AT_???");
104 	}
105 	return 0;
106 }
107 
SYS_FUNC(open_by_handle_at)108 SYS_FUNC(open_by_handle_at)
109 {
110 	file_handle_header h;
111 	const long addr = tcp->u_arg[1];
112 
113 	/* mount_fd */
114 	printfd(tcp, tcp->u_arg[0]);
115 	tprints(", ");
116 
117 	/* handle */
118 	if (!umove_or_printaddr(tcp, addr, &h)) {
119 		unsigned char f_handle[MAX_HANDLE_SZ];
120 
121 		tprintf("{handle_bytes=%u, handle_type=%d",
122 			h.handle_bytes, h.handle_type);
123 		if (h.handle_bytes > MAX_HANDLE_SZ)
124 			h.handle_bytes = MAX_HANDLE_SZ;
125 		if (!umoven(tcp, addr + sizeof(h), h.handle_bytes, &f_handle)) {
126 			unsigned int i;
127 
128 			tprints(", f_handle=0x");
129 			for (i = 0; i < h.handle_bytes; ++i)
130 				tprintf("%02x", f_handle[i]);
131 		}
132 		tprints("}");
133 	}
134 	tprints(", ");
135 
136 	/* flags */
137 	tprint_open_modes(tcp->u_arg[2]);
138 
139 	return RVAL_DECODED;
140 }
141