Updating trunk VERSION from 1014.0 to 1015.0
[chromium-blink-merge.git] / net / base / dns_util.cc
blob816095b0bd8156c24532bc2d52682704a799d1a7
1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "net/base/dns_util.h"
7 #include <cstring>
9 namespace net {
11 // Based on DJB's public domain code.
12 bool DNSDomainFromDot(const base::StringPiece& dotted, std::string* out) {
13 const char* buf = dotted.data();
14 unsigned n = dotted.size();
15 char label[63];
16 unsigned int labellen = 0; /* <= sizeof label */
17 char name[255];
18 unsigned int namelen = 0; /* <= sizeof name */
19 char ch;
21 for (;;) {
22 if (!n)
23 break;
24 ch = *buf++;
25 --n;
26 if (ch == '.') {
27 if (labellen) {
28 if (namelen + labellen + 1 > sizeof name)
29 return false;
30 name[namelen++] = labellen;
31 memcpy(name + namelen, label, labellen);
32 namelen += labellen;
33 labellen = 0;
35 continue;
37 if (labellen >= sizeof label)
38 return false;
39 label[labellen++] = ch;
42 if (labellen) {
43 if (namelen + labellen + 1 > sizeof name)
44 return false;
45 name[namelen++] = labellen;
46 memcpy(name + namelen, label, labellen);
47 namelen += labellen;
48 labellen = 0;
51 if (namelen + 1 > sizeof name)
52 return false;
53 name[namelen++] = 0; // This is the root label (of length 0).
55 *out = std::string(name, namelen);
56 return true;
59 std::string DNSDomainToString(const base::StringPiece& domain) {
60 std::string ret;
62 for (unsigned i = 0; i < domain.size() && domain[i]; i += domain[i] + 1) {
63 #if CHAR_MIN < 0
64 if (domain[i] < 0)
65 return "";
66 #endif
67 if (domain[i] > 63)
68 return "";
70 if (i)
71 ret += ".";
73 if (static_cast<unsigned>(domain[i]) + i + 1 > domain.size())
74 return "";
76 domain.substr(i + 1, domain[i]).AppendToString(&ret);
78 return ret;
81 bool IsSTD3ASCIIValidCharacter(char c) {
82 if (c <= 0x2c)
83 return false;
84 if (c >= 0x7b)
85 return false;
86 if (c >= 0x2e && c <= 0x2f)
87 return false;
88 if (c >= 0x3a && c <= 0x40)
89 return false;
90 if (c >= 0x5b && c <= 0x60)
91 return false;
92 return true;
95 std::string TrimEndingDot(const base::StringPiece& host) {
96 base::StringPiece host_trimmed = host;
97 size_t len = host_trimmed.length();
98 if (len > 1 && host_trimmed[len - 1] == '.') {
99 host_trimmed.remove_suffix(1);
101 return host_trimmed.as_string();
104 } // namespace net