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, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
6  * Copyright (c) 2005-2007 Roland McGrath <roland@redhat.com>
7  * Copyright (c) 2006-2007 Ulrich Drepper <drepper@redhat.com>
8  * Copyright (c) 2009-2013 Denys Vlasenko <dvlasenk@redhat.com>
9  * Copyright (c) 2005-2015 Dmitry V. Levin <ldv@altlinux.org>
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include "defs.h"
36 
37 #include <fcntl.h>
38 
39 /* some libcs are guilty of messing up with O_ACCMODE */
40 #undef O_ACCMODE
41 #define O_ACCMODE 03
42 
43 #ifdef O_LARGEFILE
44 # if O_LARGEFILE == 0          /* biarch platforms in 64-bit mode */
45 #  undef O_LARGEFILE
46 #  ifdef SPARC64
47 #   define O_LARGEFILE 0x40000
48 #  elif defined X86_64 || defined S390X
49 #   define O_LARGEFILE 0100000
50 #  endif
51 # endif
52 #endif
53 
54 #include "xlat/open_access_modes.h"
55 #include "xlat/open_mode_flags.h"
56 
57 #ifndef AT_FDCWD
58 # define AT_FDCWD                -100
59 #endif
60 
61 /* The fd is an "int", so when decoding x86 on x86_64, we need to force sign
62  * extension to get the right value.  We do this by declaring fd as int here.
63  */
64 void
print_dirfd(struct tcb * tcp,int fd)65 print_dirfd(struct tcb *tcp, int fd)
66 {
67 	if (fd == AT_FDCWD)
68 		tprints("AT_FDCWD, ");
69 	else {
70 		printfd(tcp, fd);
71 		tprints(", ");
72 	}
73 }
74 
75 /*
76  * low bits of the open(2) flags define access mode,
77  * other bits are real flags.
78  */
79 const char *
sprint_open_modes(unsigned int flags)80 sprint_open_modes(unsigned int flags)
81 {
82 	static char outstr[(1 + ARRAY_SIZE(open_mode_flags)) * sizeof("O_LARGEFILE")];
83 	char *p;
84 	char sep;
85 	const char *str;
86 	const struct xlat *x;
87 
88 	sep = ' ';
89 	p = stpcpy(outstr, "flags");
90 	str = xlookup(open_access_modes, flags & 3);
91 	if (str) {
92 		*p++ = sep;
93 		p = stpcpy(p, str);
94 		flags &= ~3;
95 		if (!flags)
96 			return outstr;
97 		sep = '|';
98 	}
99 
100 	for (x = open_mode_flags; x->str; x++) {
101 		if ((flags & x->val) == x->val) {
102 			*p++ = sep;
103 			p = stpcpy(p, x->str);
104 			flags &= ~x->val;
105 			if (!flags)
106 				return outstr;
107 			sep = '|';
108 		}
109 	}
110 	/* flags is still nonzero */
111 	*p++ = sep;
112 	sprintf(p, "%#x", flags);
113 	return outstr;
114 }
115 
116 void
tprint_open_modes(unsigned int flags)117 tprint_open_modes(unsigned int flags)
118 {
119 	tprints(sprint_open_modes(flags) + sizeof("flags"));
120 }
121 
122 #ifdef O_TMPFILE
123 /* The kernel & C libraries often inline O_DIRECTORY. */
124 # define STRACE_O_TMPFILE (O_TMPFILE & ~O_DIRECTORY)
125 #else /* !O_TMPFILE */
126 # define STRACE_O_TMPFILE 0
127 #endif
128 
129 static int
decode_open(struct tcb * tcp,int offset)130 decode_open(struct tcb *tcp, int offset)
131 {
132 	printpath(tcp, tcp->u_arg[offset]);
133 	tprints(", ");
134 	/* flags */
135 	tprint_open_modes(tcp->u_arg[offset + 1]);
136 	if (tcp->u_arg[offset + 1] & (O_CREAT | STRACE_O_TMPFILE)) {
137 		/* mode */
138 		tprints(", ");
139 		print_numeric_umode_t(tcp->u_arg[offset + 2]);
140 	}
141 
142 	return RVAL_DECODED | RVAL_FD;
143 }
144 
SYS_FUNC(open)145 SYS_FUNC(open)
146 {
147 	return decode_open(tcp, 0);
148 }
149 
SYS_FUNC(openat)150 SYS_FUNC(openat)
151 {
152 	print_dirfd(tcp, tcp->u_arg[0]);
153 	return decode_open(tcp, 1);
154 }
155 
SYS_FUNC(creat)156 SYS_FUNC(creat)
157 {
158 	printpath(tcp, tcp->u_arg[0]);
159 	tprints(", ");
160 	print_numeric_umode_t(tcp->u_arg[1]);
161 
162 	return RVAL_DECODED | RVAL_FD;
163 }
164