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) 1999-2017 The strace developers.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. The name of the author may not be used to endorse or promote products
18 * derived from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include "defs.h"
33
SYS_FUNC(close)34 SYS_FUNC(close)
35 {
36 printfd(tcp, tcp->u_arg[0]);
37
38 return RVAL_DECODED;
39 }
40
SYS_FUNC(dup)41 SYS_FUNC(dup)
42 {
43 printfd(tcp, tcp->u_arg[0]);
44
45 return RVAL_DECODED | RVAL_FD;
46 }
47
48 static int
do_dup2(struct tcb * tcp,int flags_arg)49 do_dup2(struct tcb *tcp, int flags_arg)
50 {
51 printfd(tcp, tcp->u_arg[0]);
52 tprints(", ");
53 printfd(tcp, tcp->u_arg[1]);
54 if (flags_arg >= 0) {
55 tprints(", ");
56 printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
57 }
58
59 return RVAL_DECODED | RVAL_FD;
60 }
61
SYS_FUNC(dup2)62 SYS_FUNC(dup2)
63 {
64 return do_dup2(tcp, -1);
65 }
66
SYS_FUNC(dup3)67 SYS_FUNC(dup3)
68 {
69 return do_dup2(tcp, 2);
70 }
71
72 static int
decode_select(struct tcb * const tcp,const kernel_ulong_t * const args,void (* const print_tv_ts)(struct tcb *,kernel_ulong_t),const char * (* const sprint_tv_ts)(struct tcb *,kernel_ulong_t))73 decode_select(struct tcb *const tcp, const kernel_ulong_t *const args,
74 void (*const print_tv_ts) (struct tcb *, kernel_ulong_t),
75 const char * (*const sprint_tv_ts) (struct tcb *, kernel_ulong_t))
76 {
77 int i, j;
78 int nfds, fdsize;
79 fd_set *fds = NULL;
80 const char *sep;
81 kernel_ulong_t addr;
82
83 /* Kernel truncates args[0] to int, we do the same. */
84 nfds = (int) args[0];
85
86 /* Kernel rejects negative nfds, so we don't parse it either. */
87 if (nfds < 0)
88 nfds = 0;
89
90 /* Beware of select(2^31-1, NULL, NULL, NULL) and similar... */
91 if (nfds > 1024*1024)
92 nfds = 1024*1024;
93
94 /*
95 * We had bugs a-la "while (j < args[0])" and "umoven(args[0])" below.
96 * Instead of args[0], use nfds for fd count, fdsize for array lengths.
97 */
98 fdsize = (((nfds + 7) / 8) + current_wordsize-1) & -current_wordsize;
99
100 if (entering(tcp)) {
101 tprintf("%d", (int) args[0]);
102
103 if (verbose(tcp) && fdsize > 0)
104 fds = malloc(fdsize);
105 for (i = 0; i < 3; i++) {
106 addr = args[i+1];
107 tprints(", ");
108 if (!fds) {
109 printaddr(addr);
110 continue;
111 }
112 if (umoven_or_printaddr(tcp, addr, fdsize, fds))
113 continue;
114 tprints("[");
115 for (j = 0, sep = "";; j++) {
116 j = next_set_bit(fds, j, nfds);
117 if (j < 0)
118 break;
119 tprints(sep);
120 printfd(tcp, j);
121 sep = " ";
122 }
123 tprints("]");
124 }
125 free(fds);
126 tprints(", ");
127 print_tv_ts(tcp, args[4]);
128 } else {
129 static char outstr[1024];
130 char *outptr;
131 #define end_outstr (outstr + sizeof(outstr))
132 int ready_fds;
133
134 if (syserror(tcp))
135 return 0;
136
137 ready_fds = tcp->u_rval;
138 if (ready_fds == 0) {
139 tcp->auxstr = "Timeout";
140 return RVAL_STR;
141 }
142
143 fds = malloc(fdsize);
144
145 outptr = outstr;
146 sep = "";
147 for (i = 0; i < 3 && ready_fds > 0; i++) {
148 int first = 1;
149
150 addr = args[i+1];
151 if (!addr || !fds || umoven(tcp, addr, fdsize, fds) < 0)
152 continue;
153 for (j = 0;; j++) {
154 j = next_set_bit(fds, j, nfds);
155 if (j < 0)
156 break;
157 /* +2 chars needed at the end: ']',NUL */
158 if (outptr < end_outstr - (sizeof(", except [") + sizeof(int)*3 + 2)) {
159 if (first) {
160 outptr += sprintf(outptr, "%s%s [%u",
161 sep,
162 i == 0 ? "in" : i == 1 ? "out" : "except",
163 j
164 );
165 first = 0;
166 sep = ", ";
167 } else {
168 outptr += sprintf(outptr, " %u", j);
169 }
170 }
171 if (--ready_fds == 0)
172 break;
173 }
174 if (outptr != outstr)
175 *outptr++ = ']';
176 }
177 free(fds);
178 /* This contains no useful information on SunOS. */
179 if (args[4]) {
180 const char *str = sprint_tv_ts(tcp, args[4]);
181 if (outptr + sizeof("left ") + strlen(sep) + strlen(str) < end_outstr) {
182 outptr += sprintf(outptr, "%sleft %s", sep, str);
183 }
184 }
185 *outptr = '\0';
186 tcp->auxstr = outstr;
187 return RVAL_STR;
188 #undef end_outstr
189 }
190 return 0;
191 }
192
SYS_FUNC(oldselect)193 SYS_FUNC(oldselect)
194 {
195 kernel_ulong_t select_args[5];
196 unsigned int oldselect_args[5];
197
198 if (sizeof(*select_args) == sizeof(*oldselect_args)) {
199 if (umove_or_printaddr(tcp, tcp->u_arg[0], &select_args)) {
200 return 0;
201 }
202 } else {
203 unsigned int i;
204
205 if (umove_or_printaddr(tcp, tcp->u_arg[0], &oldselect_args)) {
206 return 0;
207 }
208
209 for (i = 0; i < 5; ++i) {
210 select_args[i] = oldselect_args[i];
211 }
212 }
213
214 return decode_select(tcp, select_args, print_timeval, sprint_timeval);
215 }
216
217 #ifdef ALPHA
SYS_FUNC(osf_select)218 SYS_FUNC(osf_select)
219 {
220 return decode_select(tcp, tcp->u_arg, print_timeval32, sprint_timeval32);
221 }
222 #endif
223
SYS_FUNC(select)224 SYS_FUNC(select)
225 {
226 return decode_select(tcp, tcp->u_arg, print_timeval, sprint_timeval);
227 }
228
229 static int
umove_kulong_array_or_printaddr(struct tcb * const tcp,const kernel_ulong_t addr,kernel_ulong_t * const ptr,const size_t n)230 umove_kulong_array_or_printaddr(struct tcb *const tcp, const kernel_ulong_t addr,
231 kernel_ulong_t *const ptr, const size_t n)
232 {
233 #ifndef current_klongsize
234 if (current_klongsize < sizeof(*ptr)) {
235 uint32_t ptr32[n];
236 int r = umove_or_printaddr(tcp, addr, &ptr32);
237 if (!r) {
238 size_t i;
239
240 for (i = 0; i < n; ++i)
241 ptr[i] = ptr32[i];
242 }
243 return r;
244 }
245 #endif /* !current_klongsize */
246 return umoven_or_printaddr(tcp, addr, n * sizeof(*ptr), ptr);
247 }
248
SYS_FUNC(pselect6)249 SYS_FUNC(pselect6)
250 {
251 int rc = decode_select(tcp, tcp->u_arg, print_timespec, sprint_timespec);
252 if (entering(tcp)) {
253 kernel_ulong_t data[2];
254
255 tprints(", ");
256 if (!umove_kulong_array_or_printaddr(tcp, tcp->u_arg[5],
257 data, ARRAY_SIZE(data))) {
258 tprints("{");
259 /* NB: kernel requires data[1] == NSIG_BYTES */
260 print_sigset_addr_len(tcp, data[0], data[1]);
261 tprintf(", %" PRI_klu "}", data[1]);
262 }
263 }
264
265 return rc;
266 }
267