Tor  0.4.7.0-alpha-dev
recommend_pkg.c
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1 /* Copyright (c) 2001-2004, Roger Dingledine.
2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
3  * Copyright (c) 2007-2021, The Tor Project, Inc. */
4 /* See LICENSE for licensing information */
5 
6 /**
7  * \file recommend_pkg.c
8  * \brief Code related to the recommended-packages subsystem.
9  *
10  * Currently unused.
11  **/
12 
13 #include "core/or/or.h"
15 
16 /** Return true iff <b>line</b> is a valid RecommendedPackages line.
17  */
18 /*
19  The grammar is:
20 
21  "package" SP PACKAGENAME SP VERSION SP URL SP DIGESTS NL
22 
23  PACKAGENAME = NONSPACE
24  VERSION = NONSPACE
25  URL = NONSPACE
26  DIGESTS = DIGEST | DIGESTS SP DIGEST
27  DIGEST = DIGESTTYPE "=" DIGESTVAL
28 
29  NONSPACE = one or more non-space printing characters
30 
31  DIGESTVAL = DIGESTTYPE = one or more non-=, non-" " characters.
32 
33  SP = " "
34  NL = a newline
35 
36  */
37 int
39 {
40  const char *cp = line;
41 
42 #define WORD() \
43  do { \
44  if (*cp == ' ') \
45  return 0; \
46  cp = strchr(cp, ' '); \
47  if (!cp) \
48  return 0; \
49  } while (0)
50 
51  WORD(); /* skip packagename */
52  ++cp;
53  WORD(); /* skip version */
54  ++cp;
55  WORD(); /* Skip URL */
56  ++cp;
57 
58  /* Skip digesttype=digestval + */
59  int n_entries = 0;
60  while (1) {
61  const char *start_of_word = cp;
62  const char *end_of_word = strchr(cp, ' ');
63  if (! end_of_word)
64  end_of_word = cp + strlen(cp);
65 
66  if (start_of_word == end_of_word)
67  return 0;
68 
69  const char *eq = memchr(start_of_word, '=', end_of_word - start_of_word);
70 
71  if (!eq)
72  return 0;
73  if (eq == start_of_word)
74  return 0;
75  if (eq == end_of_word - 1)
76  return 0;
77  if (memchr(eq+1, '=', end_of_word - (eq+1)))
78  return 0;
79 
80  ++n_entries;
81  if (0 == *end_of_word)
82  break;
83 
84  cp = end_of_word + 1;
85  }
86 
87  /* If we reach this point, we have at least 1 entry. */
88  tor_assert(n_entries > 0);
89  return 1;
90 }
Master header file for Tor-specific functionality.
int validate_recommended_package_line(const char *line)
Definition: recommend_pkg.c:38
Header file for recommend_pkg.c.
#define tor_assert(expr)
Definition: util_bug.h:102