1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
|
/*
* Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the Computer Systems
* Engineering Group at Lawrence Berkeley Laboratory.
* 4. Neither the name of the University nor of the Laboratory may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Utilities for message formatting used both by libpcap and rpcapd.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "ftmacros.h"
#include <stddef.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <pcap/pcap.h>
#include "portability.h"
#include "fmtutils.h"
/*
* Generate an error message based on a format, arguments, and an
* errno, with a message for the errno after the formatted output.
*/
void
pcap_fmt_errmsg_for_errno(char *errbuf, size_t errbuflen, int errnum,
const char *fmt, ...)
{
va_list ap;
size_t msglen;
char *p;
size_t errbuflen_remaining;
va_start(ap, fmt);
pcap_vsnprintf(errbuf, errbuflen, fmt, ap);
va_end(ap);
msglen = strlen(errbuf);
/*
* Do we have enough space to append ": "?
* Including the terminating '\0', that's 3 bytes.
*/
if (msglen + 3 > errbuflen) {
/* No - just give them what we've produced. */
return;
}
p = errbuf + msglen;
errbuflen_remaining = errbuflen - msglen;
*p++ = ':';
*p++ = ' ';
*p = '\0';
msglen += 2;
errbuflen_remaining -= 2;
/*
* Now append the string for the error code.
*/
#if defined(HAVE_STRERROR_S)
/*
* We have a Windows-style strerror_s().
*/
errno_t err = strerror_s(p, errbuflen_remaining, errnum);
if (err != 0) {
/*
* It doesn't appear to be documented anywhere obvious
* what the error returns from strerror_s().
*/
pcap_snprintf(p, errbuflen_remaining, "Error %d", errnum);
}
#elif defined(HAVE_GNU_STRERROR_R)
/*
* We have a GNU-style strerror_r(), which is *not* guaranteed to
* do anything to the buffer handed to it, and which returns a
* pointer to the error string, which may or may not be in
* the buffer.
*
* It is, however, guaranteed to succeed.
*/
char strerror_buf[PCAP_ERRBUF_SIZE];
char *errstring = strerror_r(errnum, strerror_buf, PCAP_ERRBUF_SIZE);
pcap_snprintf(p, errbuflen_remaining, "%s", errstring);
#elif defined(HAVE_POSIX_STRERROR_R)
/*
* We have a POSIX-style strerror_r(), which is guaranteed to fill
* in the buffer, but is not guaranteed to succeed.
*/
int err = strerror_r(errnum, p, errbuflen_remaining);
if (err == EINVAL) {
/*
* UNIX 03 says this isn't guaranteed to produce a
* fallback error message.
*/
pcap_snprintf(p, errbuflen_remaining, "Unknown error: %d",
errnum);
} else if (err == ERANGE) {
/*
* UNIX 03 says this isn't guaranteed to produce a
* fallback error message.
*/
pcap_snprintf(p, errbuflen_remaining,
"Message for error %d is too long", errnum);
}
#else
/*
* We have neither strerror_s() nor strerror_r(), so we're
* stuck with using pcap_strerror().
*/
pcap_snprintf(p, errbuflen_remaining, "%s", pcap_strerror(errnum));
#endif
}
#ifdef _WIN32
/*
* Generate an error message based on a format, arguments, and a
* Win32 error, with a message for the Win32 error after the formatted output.
*/
void
pcap_fmt_errmsg_for_win32_err(char *errbuf, size_t errbuflen, DWORD errnum,
const char *fmt, ...)
{
va_list ap;
size_t msglen;
char *p;
size_t errbuflen_remaining;
DWORD retval;
char win32_errbuf[PCAP_ERRBUF_SIZE+1];
va_start(ap, fmt);
pcap_vsnprintf(errbuf, errbuflen, fmt, ap);
va_end(ap);
msglen = strlen(errbuf);
/*
* Do we have enough space to append ": "?
* Including the terminating '\0', that's 3 bytes.
*/
if (msglen + 3 > errbuflen) {
/* No - just give them what we've produced. */
return;
}
p = errbuf + msglen;
errbuflen_remaining = errbuflen - msglen;
*p++ = ':';
*p++ = ' ';
*p = '\0';
msglen += 2;
errbuflen_remaining -= 2;
/*
* Now append the string for the error code.
*
* XXX - what language ID to use?
*
* For UN*Xes, pcap_strerror() may or may not return localized
* strings.
*
* We currently don't have localized messages for libpcap, but
* we might want to do so. On the other hand, if most of these
* messages are going to be read by libpcap developers and
* perhaps by developers of libpcap-based applications, English
* might be a better choice, so the developer doesn't have to
* get the message translated if it's in a language they don't
* happen to understand.
*/
retval = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS|FORMAT_MESSAGE_MAX_WIDTH_MASK,
NULL, errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
win32_errbuf, PCAP_ERRBUF_SIZE, NULL);
if (retval == 0) {
/*
* Failed.
*/
pcap_snprintf(p, errbuflen_remaining,
"Couldn't get error message for error (%lu)", errnum);
return;
}
pcap_snprintf(p, errbuflen_remaining, "%s (%lu)", win32_errbuf, errnum);
}
#endif
|
