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
|
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <stdio.h>
#include "error/s2n_errno.h"
#include "utils/s2n_rfc5952.h"
#include "utils/s2n_safety.h"
static uint8_t dec[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
static uint8_t hex[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
S2N_RESULT s2n_inet_ntop(int af, const void *addr, struct s2n_blob *dst)
{
const uint8_t *bytes = addr;
uint8_t *cursor = dst->data;
if (af == AF_INET) {
RESULT_ENSURE(dst->size >= sizeof("111.222.333.444"), S2N_ERR_SIZE_MISMATCH);
for (int i = 0; i < 4; i++) {
if (bytes[i] / 100) {
*cursor++ = dec[bytes[i] / 100];
}
if (bytes[i] >= 10) {
*cursor++ = dec[(bytes[i] % 100) / 10];
}
*cursor++ = dec[(bytes[i] % 10)];
*cursor++ = '.';
}
*--cursor = '\0';
return S2N_RESULT_OK;
}
if (af == AF_INET6) {
RESULT_ENSURE(dst->size >= sizeof("1111:2222:3333:4444:5555:6666:7777:8888"), S2N_ERR_SIZE_MISMATCH);
/* See Section 4 of RFC5952 for the rules we are going to follow here
*
* Here's the general algorithm:
*
* 1/ Treat the bytes as 8 16-bit fields
* 2/ Find the longest run of 16-bit fields.
* 3/ or if there are two or more equal length longest runs, go with the left-most run
* 4/ Make that run ::
* 5/ Print the remaining 16-bit fields in lowercase hex, no leading zeroes
*/
uint16_t octets[8] = { 0 };
int longest_run_start = 0;
int longest_run_length = 0;
int current_run_length = 0;
/* 2001:db8::1:0:0:1 */
/* Find the longest run of zeroes */
for (int i = 0; i < 8; i++) {
octets[i] = (bytes[i * 2] << 8) + bytes[(i * 2) + 1];
if (octets[i]) {
current_run_length = 0;
}
else {
current_run_length++;
}
if (current_run_length > longest_run_length) {
longest_run_length = current_run_length;
longest_run_start = (i - current_run_length) + 1;
}
}
for (int i = 0; i < 8; i++) {
if (i == longest_run_start && longest_run_length > 1) {
if (i == 0) {
*cursor++ = ':';
}
if (longest_run_length == 8) {
*cursor++ = ':';
}
i += longest_run_length - 1;
}
else {
uint8_t nibbles[4] = { (octets[i] & 0xF000) >> 12,
(octets[i] & 0x0F00) >> 8,
(octets[i] & 0x00F0) >> 4,
(octets[i] & 0x000F) };
/* Skip up to three leading zeroes */
int j;
for (j = 0; j < 3; j++) {
if (nibbles[j]) {
break;
}
}
for (; j < 4; j++) {
*cursor++ = hex[ nibbles[j] ];
}
}
*cursor++ = ':';
}
*--cursor = '\0';
return S2N_RESULT_OK;
}
RESULT_BAIL(S2N_ERR_INVALID_ARGUMENT);
}
|
