libpcap  1.10.1
About: libpcap is a packet filter library used by tools like tcpdump.
  Fossies Dox: libpcap-1.10.1.tar.gz  ("unofficial" and yet experimental doxygen-generated source code documentation)  

etherent.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 1990, 1993, 1994, 1995, 1996
3  * The Regents of the University of California. All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #ifdef HAVE_CONFIG_H
23 #include <config.h>
24 #endif
25 
26 #include <pcap-types.h>
27 
28 #include <memory.h>
29 #include <stdio.h>
30 #include <string.h>
31 
32 #include "pcap-int.h"
33 
34 #include <pcap/namedb.h>
35 
36 #ifdef HAVE_OS_PROTO_H
37 #include "os-proto.h"
38 #endif
39 
40 static inline int skip_space(FILE *);
41 static inline int skip_line(FILE *);
42 
43 /* Hex digit to integer. */
44 static inline u_char
45 xdtoi(u_char c)
46 {
47  if (c >= '0' && c <= '9')
48  return (u_char)(c - '0');
49  else if (c >= 'a' && c <= 'f')
50  return (u_char)(c - 'a' + 10);
51  else
52  return (u_char)(c - 'A' + 10);
53 }
54 
55 /*
56  * Skip linear white space (space and tab) and any CRs before LF.
57  * Stop when we hit a non-white-space character or an end-of-line LF.
58  */
59 static inline int
60 skip_space(FILE *f)
61 {
62  int c;
63 
64  do {
65  c = getc(f);
66  } while (c == ' ' || c == '\t' || c == '\r');
67 
68  return c;
69 }
70 
71 static inline int
72 skip_line(FILE *f)
73 {
74  int c;
75 
76  do
77  c = getc(f);
78  while (c != '\n' && c != EOF);
79 
80  return c;
81 }
82 
83 struct pcap_etherent *
85 {
86  register int c, i;
87  u_char d;
88  char *bp;
89  size_t namesize;
90  static struct pcap_etherent e;
91 
92  memset((char *)&e, 0, sizeof(e));
93  for (;;) {
94  /* Find addr */
95  c = skip_space(fp);
96  if (c == EOF)
97  return (NULL);
98  if (c == '\n')
99  continue;
100 
101  /* If this is a comment, or first thing on line
102  cannot be Ethernet address, skip the line. */
103  if (!PCAP_ISXDIGIT(c)) {
104  c = skip_line(fp);
105  if (c == EOF)
106  return (NULL);
107  continue;
108  }
109 
110  /* must be the start of an address */
111  for (i = 0; i < 6; i += 1) {
112  d = xdtoi((u_char)c);
113  c = getc(fp);
114  if (c == EOF)
115  return (NULL);
116  if (PCAP_ISXDIGIT(c)) {
117  d <<= 4;
118  d |= xdtoi((u_char)c);
119  c = getc(fp);
120  if (c == EOF)
121  return (NULL);
122  }
123  e.addr[i] = d;
124  if (c != ':')
125  break;
126  c = getc(fp);
127  if (c == EOF)
128  return (NULL);
129  }
130 
131  /* Must be whitespace */
132  if (c != ' ' && c != '\t' && c != '\r' && c != '\n') {
133  c = skip_line(fp);
134  if (c == EOF)
135  return (NULL);
136  continue;
137  }
138  c = skip_space(fp);
139  if (c == EOF)
140  return (NULL);
141 
142  /* hit end of line... */
143  if (c == '\n')
144  continue;
145 
146  if (c == '#') {
147  c = skip_line(fp);
148  if (c == EOF)
149  return (NULL);
150  continue;
151  }
152 
153  /* pick up name */
154  bp = e.name;
155  /* Use 'namesize' to prevent buffer overflow. */
156  namesize = sizeof(e.name) - 1;
157  do {
158  *bp++ = (u_char)c;
159  c = getc(fp);
160  if (c == EOF)
161  return (NULL);
162  } while (c != ' ' && c != '\t' && c != '\r' && c != '\n'
163  && --namesize != 0);
164  *bp = '\0';
165 
166  /* Eat trailing junk */
167  if (c != '\n')
168  (void)skip_line(fp);
169 
170  return &e;
171  }
172 }
static u_char xdtoi(u_char c)
Definition: etherent.c:45
struct pcap_etherent * pcap_next_etherent(FILE *fp)
Definition: etherent.c:84
static int skip_space(FILE *)
Definition: etherent.c:60
static int skip_line(FILE *)
Definition: etherent.c:72
#define PCAP_ISXDIGIT(c)
Definition: pcap-int.h:140
u_char addr[6]
Definition: namedb.h:52
char name[122]
Definition: namedb.h:53