2 * Copyright 2014 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #include "MacAddress.h"
19 #include <folly/Exception.h>
20 #include <folly/IPAddressV6.h>
22 using std::invalid_argument;
27 const MacAddress MacAddress::BROADCAST{Endian::big(uint64_t(0xffffffffffffU))};
28 const MacAddress MacAddress::ZERO;
30 MacAddress::MacAddress(StringPiece str) {
31 memset(&bytes_, 0, 8);
35 MacAddress MacAddress::createMulticast(IPAddressV6 v6addr) {
36 // This method should only be used for multicast addresses.
37 DCHECK(v6addr.isMulticast());
42 memcpy(bytes + 2, v6addr.bytes() + 12, 4);
43 return fromBinary(ByteRange(bytes, SIZE));
46 string MacAddress::toString() const {
47 static const char hexValues[] = "0123456789abcdef";
50 result[0] = hexValues[getByte(0) >> 4];
51 result[1] = hexValues[getByte(0) & 0xf];
53 result[3] = hexValues[getByte(1) >> 4];
54 result[4] = hexValues[getByte(1) & 0xf];
56 result[6] = hexValues[getByte(2) >> 4];
57 result[7] = hexValues[getByte(2) & 0xf];
59 result[9] = hexValues[getByte(3) >> 4];
60 result[10] = hexValues[getByte(3) & 0xf];
62 result[12] = hexValues[getByte(4) >> 4];
63 result[13] = hexValues[getByte(4) & 0xf];
65 result[15] = hexValues[getByte(5) >> 4];
66 result[16] = hexValues[getByte(5) & 0xf];
70 void MacAddress::parse(StringPiece str) {
71 // Helper function to convert a single hex char into an integer
72 auto unhex = [](char c) -> int {
73 return c >= '0' && c <= '9' ? c - '0' :
74 c >= 'A' && c <= 'F' ? c - 'A' + 10 :
75 c >= 'a' && c <= 'f' ? c - 'a' + 10 :
78 auto isSeparatorChar = [](char c) {
79 return c == ':' || c == '-';
84 for (unsigned int byteIndex = 0; byteIndex < SIZE; ++byteIndex) {
86 throw invalid_argument(to<string>("invalid MAC address \"", str,
87 "\": not enough digits"));
90 // Skip over ':' or '-' separators between bytes
91 if (byteIndex != 0 && isSeparatorChar(*p)) {
94 throw invalid_argument(to<string>("invalid MAC address \"", str,
95 "\": not enough digits"));
99 // Parse the upper nibble
100 int upper = unhex(*p);
102 throw invalid_argument(to<string>("invalid MAC address \"", str,
103 "\": contains non-hex digit"));
107 // Parse the lower nibble
109 if (p == str.end()) {
115 // Also accept ':', '-', or '\0', to handle the case where one
116 // of the bytes was represented by just a single digit.
117 if (isSeparatorChar(*p)) {
121 throw invalid_argument(to<string>("invalid MAC address \"", str,
122 "\": contains non-hex digit"));
128 // Update parsed with the newly parsed byte
129 parsed[byteIndex] = ((upper << 4) | lower);
132 if (p != str.end()) {
133 // String is too long to be a MAC address
134 throw invalid_argument(to<string>("invalid MAC address \"", str,
135 "\": found trailing characters"));
138 // Only update now that we have successfully parsed the entire
139 // string. This way we remain unchanged on error.
140 setFromBinary(ByteRange(parsed, SIZE));
143 void MacAddress::setFromBinary(ByteRange value) {
144 if (value.size() != SIZE) {
145 throw invalid_argument(to<string>("MAC address must be 6 bytes "
146 "long, got ", value.size()));
148 memcpy(bytes_ + 2, value.begin(), SIZE);
151 std::ostream& operator<<(std::ostream& os, MacAddress address) {
152 os << address.toString();