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 * Copyright (c) 2014-2017 The strace developers.
11 * All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. The name of the author may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #include "defs.h"
37
38 #include <fcntl.h>
39
40 /* some libcs are guilty of messing up with O_ACCMODE */
41 #undef O_ACCMODE
42 #define O_ACCMODE 03
43
44 #ifdef O_LARGEFILE
45 # if O_LARGEFILE == 0 /* biarch platforms in 64-bit mode */
46 # undef O_LARGEFILE
47 # ifdef SPARC64
48 # define O_LARGEFILE 0x40000
49 # elif defined X86_64 || defined S390X
50 # define O_LARGEFILE 0100000
51 # endif
52 # endif
53 #endif
54
55 #include "xlat/open_access_modes.h"
56 #include "xlat/open_mode_flags.h"
57
58 #ifndef AT_FDCWD
59 # define AT_FDCWD -100
60 #endif
61
62 /* The fd is an "int", so when decoding x86 on x86_64, we need to force sign
63 * extension to get the right value. We do this by declaring fd as int here.
64 */
65 void
print_dirfd(struct tcb * tcp,int fd)66 print_dirfd(struct tcb *tcp, int fd)
67 {
68 if (fd == AT_FDCWD)
69 tprints("AT_FDCWD, ");
70 else {
71 printfd(tcp, fd);
72 tprints(", ");
73 }
74 }
75
76 /*
77 * low bits of the open(2) flags define access mode,
78 * other bits are real flags.
79 */
80 const char *
sprint_open_modes(unsigned int flags)81 sprint_open_modes(unsigned int flags)
82 {
83 static char outstr[(1 + ARRAY_SIZE(open_mode_flags)) * sizeof("O_LARGEFILE")];
84 char *p;
85 char sep;
86 const char *str;
87 const struct xlat *x;
88
89 sep = ' ';
90 p = stpcpy(outstr, "flags");
91 str = xlookup(open_access_modes, flags & 3);
92 if (str) {
93 *p++ = sep;
94 p = stpcpy(p, str);
95 flags &= ~3;
96 if (!flags)
97 return outstr;
98 sep = '|';
99 }
100
101 for (x = open_mode_flags; x->str; x++) {
102 if ((flags & x->val) == x->val) {
103 *p++ = sep;
104 p = stpcpy(p, x->str);
105 flags &= ~x->val;
106 if (!flags)
107 return outstr;
108 sep = '|';
109 }
110 }
111 /* flags is still nonzero */
112 *p++ = sep;
113 sprintf(p, "%#x", flags);
114 return outstr;
115 }
116
117 void
tprint_open_modes(unsigned int flags)118 tprint_open_modes(unsigned int flags)
119 {
120 tprints(sprint_open_modes(flags) + sizeof("flags"));
121 }
122
123 #ifdef O_TMPFILE
124 /* The kernel & C libraries often inline O_DIRECTORY. */
125 # define STRACE_O_TMPFILE (O_TMPFILE & ~O_DIRECTORY)
126 #else /* !O_TMPFILE */
127 # define STRACE_O_TMPFILE 0
128 #endif
129
130 static int
decode_open(struct tcb * tcp,int offset)131 decode_open(struct tcb *tcp, int offset)
132 {
133 printpath(tcp, tcp->u_arg[offset]);
134 tprints(", ");
135 /* flags */
136 tprint_open_modes(tcp->u_arg[offset + 1]);
137 if (tcp->u_arg[offset + 1] & (O_CREAT | STRACE_O_TMPFILE)) {
138 /* mode */
139 tprints(", ");
140 print_numeric_umode_t(tcp->u_arg[offset + 2]);
141 }
142
143 return RVAL_DECODED | RVAL_FD;
144 }
145
SYS_FUNC(open)146 SYS_FUNC(open)
147 {
148 return decode_open(tcp, 0);
149 }
150
SYS_FUNC(openat)151 SYS_FUNC(openat)
152 {
153 print_dirfd(tcp, tcp->u_arg[0]);
154 return decode_open(tcp, 1);
155 }
156
SYS_FUNC(creat)157 SYS_FUNC(creat)
158 {
159 printpath(tcp, tcp->u_arg[0]);
160 tprints(", ");
161 print_numeric_umode_t(tcp->u_arg[1]);
162
163 return RVAL_DECODED | RVAL_FD;
164 }
165