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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
#include "curl_setup.h"
#include "keylog.h"
#include <curl/curl.h>
/* The last #include files should be: */
#include "curl_memory.h"
#include "memdebug.h"
#define KEYLOG_LABEL_MAXLEN (sizeof("CLIENT_HANDSHAKE_TRAFFIC_SECRET") - 1)
#define CLIENT_RANDOM_SIZE 32
/*
* The master secret in TLS 1.2 and before is always 48 bytes. In TLS 1.3, the
* secret size depends on the cipher suite's hash function which is 32 bytes
* for SHA-256 and 48 bytes for SHA-384.
*/
#define SECRET_MAXLEN 48
/* The fp for the open SSLKEYLOGFILE, or NULL if not open */
static FILE *keylog_file_fp;
void
Curl_tls_keylog_open(void)
{
char *keylog_file_name;
if(!keylog_file_fp) {
keylog_file_name = curl_getenv("SSLKEYLOGFILE");
if(keylog_file_name) {
keylog_file_fp = fopen(keylog_file_name, FOPEN_APPENDTEXT);
if(keylog_file_fp) {
#ifdef WIN32
if(setvbuf(keylog_file_fp, NULL, _IONBF, 0))
#else
if(setvbuf(keylog_file_fp, NULL, _IOLBF, 4096))
#endif
{
fclose(keylog_file_fp);
keylog_file_fp = NULL;
}
}
Curl_safefree(keylog_file_name);
}
}
}
void
Curl_tls_keylog_close(void)
{
if(keylog_file_fp) {
fclose(keylog_file_fp);
keylog_file_fp = NULL;
}
}
bool
Curl_tls_keylog_enabled(void)
{
return keylog_file_fp != NULL;
}
bool
Curl_tls_keylog_write_line(const char *line)
{
/* The current maximum valid keylog line length LF and NUL is 195. */
size_t linelen;
char buf[256];
if(!keylog_file_fp || !line) {
return false;
}
linelen = strlen(line);
if(linelen == 0 || linelen > sizeof(buf) - 2) {
/* Empty line or too big to fit in a LF and NUL. */
return false;
}
memcpy(buf, line, linelen);
if(line[linelen - 1] != '\n') {
buf[linelen++] = '\n';
}
buf[linelen] = '\0';
/* Using fputs here instead of fprintf since libcurl's fprintf replacement
may not be thread-safe. */
fputs(buf, keylog_file_fp);
return true;
}
bool
Curl_tls_keylog_write(const char *label,
const unsigned char client_random[CLIENT_RANDOM_SIZE],
const unsigned char *secret, size_t secretlen)
{
const char *hex = "0123456789ABCDEF";
size_t pos, i;
char line[KEYLOG_LABEL_MAXLEN + 1 + 2 * CLIENT_RANDOM_SIZE + 1 +
2 * SECRET_MAXLEN + 1 + 1];
if(!keylog_file_fp) {
return false;
}
pos = strlen(label);
if(pos > KEYLOG_LABEL_MAXLEN || !secretlen || secretlen > SECRET_MAXLEN) {
/* Should never happen - sanity check anyway. */
return false;
}
memcpy(line, label, pos);
line[pos++] = ' ';
/* Client Random */
for(i = 0; i < CLIENT_RANDOM_SIZE; i++) {
line[pos++] = hex[client_random[i] >> 4];
line[pos++] = hex[client_random[i] & 0xF];
}
line[pos++] = ' ';
/* Secret */
for(i = 0; i < secretlen; i++) {
line[pos++] = hex[secret[i] >> 4];
line[pos++] = hex[secret[i] & 0xF];
}
line[pos++] = '\n';
line[pos] = '\0';
/* Using fputs here instead of fprintf since libcurl's fprintf replacement
may not be thread-safe. */
fputs(line, keylog_file_fp);
return true;
}
|
