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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
|
#include "../libnetdata.h"
#ifdef ENABLE_HTTPS
SSL_CTX *netdata_opentsdb_ctx=NULL;
SSL_CTX *netdata_client_ctx=NULL;
SSL_CTX *netdata_srv_ctx=NULL;
const char *security_key=NULL;
const char *security_cert=NULL;
const char *tls_version=NULL;
const char *tls_ciphers=NULL;
int netdata_validate_server = NETDATA_SSL_VALID_CERTIFICATE;
/**
* Info Callback
*
* Function used as callback for the OpenSSL Library
*
* @param ssl a pointer to the SSL structure of the client
* @param where the variable with the flags set.
* @param ret the return of the caller
*/
static void security_info_callback(const SSL *ssl, int where, int ret __maybe_unused) {
(void)ssl;
if (where & SSL_CB_ALERT) {
debug(D_WEB_CLIENT,"SSL INFO CALLBACK %s %s", SSL_alert_type_string(ret), SSL_alert_desc_string_long(ret));
}
}
/**
* OpenSSL Library
*
* Starts the openssl library for the Netdata.
*/
void security_openssl_library()
{
#if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110
# if (SSLEAY_VERSION_NUMBER >= OPENSSL_VERSION_097)
OPENSSL_config(NULL);
# endif
SSL_load_error_strings();
SSL_library_init();
#else
if (OPENSSL_init_ssl(OPENSSL_INIT_LOAD_CONFIG, NULL) != 1) {
error("SSL library cannot be initialized.");
}
#endif
}
#if OPENSSL_VERSION_NUMBER >= OPENSSL_VERSION_110
/**
* TLS version
*
* Returns the TLS version depending of the user input.
*
* @param lversion is the user input.
*
* @return it returns the version number.
*/
int tls_select_version(const char *lversion) {
if (!strcmp(lversion, "1") || !strcmp(lversion, "1.0"))
return TLS1_VERSION;
else if (!strcmp(lversion, "1.1"))
return TLS1_1_VERSION;
else if (!strcmp(lversion, "1.2"))
return TLS1_2_VERSION;
#if defined(TLS1_3_VERSION)
else if (!strcmp(lversion, "1.3"))
return TLS1_3_VERSION;
#endif
#if defined(TLS_MAX_VERSION)
return TLS_MAX_VERSION;
#else
return TLS1_2_VERSION;
#endif
}
#endif
/**
* OpenSSL common options
*
* Clients and SERVER have common options, this function is responsible to set them in the context.
*
* @param ctx the initialized SSL context.
* @param side 0 means server, and 1 client.
*/
void security_openssl_common_options(SSL_CTX *ctx, int side) {
#if OPENSSL_VERSION_NUMBER >= OPENSSL_VERSION_110
if (!side) {
int version = tls_select_version(tls_version) ;
#endif
#if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110
SSL_CTX_set_options (ctx,SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3|SSL_OP_NO_COMPRESSION);
#else
SSL_CTX_set_min_proto_version(ctx, TLS1_VERSION);
SSL_CTX_set_max_proto_version(ctx, version);
if(tls_ciphers && strcmp(tls_ciphers, "none") != 0) {
if (!SSL_CTX_set_cipher_list(ctx, tls_ciphers)) {
error("SSL error. cannot set the cipher list");
}
}
}
#endif
SSL_CTX_set_mode(ctx, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
}
/**
* Initialize Openssl Client
*
* Starts the client context with TLS 1.2.
*
* @return It returns the context on success or NULL otherwise
*/
SSL_CTX * security_initialize_openssl_client() {
SSL_CTX *ctx;
#if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110
ctx = SSL_CTX_new(SSLv23_client_method());
#else
ctx = SSL_CTX_new(TLS_client_method());
#endif
if(ctx) {
#if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110
SSL_CTX_set_options (ctx,SSL_OP_NO_SSLv2|SSL_OP_NO_SSLv3|SSL_OP_NO_COMPRESSION);
#else
SSL_CTX_set_min_proto_version(ctx, TLS1_VERSION);
# if defined(TLS_MAX_VERSION)
SSL_CTX_set_max_proto_version(ctx, TLS_MAX_VERSION);
# elif defined(TLS1_3_VERSION)
SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION);
# elif defined(TLS1_2_VERSION)
SSL_CTX_set_max_proto_version(ctx, TLS1_2_VERSION);
# endif
#endif
}
return ctx;
}
/**
* Initialize OpenSSL server
*
* Starts the server context with TLS 1.2 and load the certificate.
*
* @return It returns the context on success or NULL otherwise
*/
static SSL_CTX * security_initialize_openssl_server() {
SSL_CTX *ctx;
char lerror[512];
static int netdata_id_context = 1;
//TO DO: Confirm the necessity to check return for other OPENSSL function
#if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110
ctx = SSL_CTX_new(SSLv23_server_method());
if (!ctx) {
error("Cannot create a new SSL context, netdata won't encrypt communication");
return NULL;
}
SSL_CTX_use_certificate_file(ctx, security_cert, SSL_FILETYPE_PEM);
#else
ctx = SSL_CTX_new(TLS_server_method());
if (!ctx) {
error("Cannot create a new SSL context, netdata won't encrypt communication");
return NULL;
}
SSL_CTX_use_certificate_chain_file(ctx, security_cert);
#endif
security_openssl_common_options(ctx, 0);
SSL_CTX_use_PrivateKey_file(ctx,security_key,SSL_FILETYPE_PEM);
if (!SSL_CTX_check_private_key(ctx)) {
ERR_error_string_n(ERR_get_error(),lerror,sizeof(lerror));
error("SSL cannot check the private key: %s",lerror);
SSL_CTX_free(ctx);
return NULL;
}
SSL_CTX_set_session_id_context(ctx,(void*)&netdata_id_context,(unsigned int)sizeof(netdata_id_context));
SSL_CTX_set_info_callback(ctx,security_info_callback);
#if (OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_095)
SSL_CTX_set_verify_depth(ctx,1);
#endif
debug(D_WEB_CLIENT,"SSL GLOBAL CONTEXT STARTED\n");
return ctx;
}
/**
* Start SSL
*
* Call the correct function to start the SSL context.
*
* @param selector informs the context that must be initialized, the following list has the valid values:
* NETDATA_SSL_CONTEXT_SERVER - the server context
* NETDATA_SSL_CONTEXT_STREAMING - Starts the streaming context.
* NETDATA_SSL_CONTEXT_OPENTSDB - Starts the OpenTSDB contextv
*/
void security_start_ssl(int selector) {
switch (selector) {
case NETDATA_SSL_CONTEXT_SERVER: {
struct stat statbuf;
if (stat(security_key, &statbuf) || stat(security_cert, &statbuf)) {
info("To use encryption it is necessary to set \"ssl certificate\" and \"ssl key\" in [web] !\n");
return;
}
netdata_srv_ctx = security_initialize_openssl_server();
break;
}
case NETDATA_SSL_CONTEXT_STREAMING: {
netdata_client_ctx = security_initialize_openssl_client();
//This is necessary for the stream, because it is working sometimes with nonblock socket.
//It returns the bitmask afte to change, there is not any description of errors in the documentation
SSL_CTX_set_mode(netdata_client_ctx, SSL_MODE_ENABLE_PARTIAL_WRITE |SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER |SSL_MODE_AUTO_RETRY);
break;
}
case NETDATA_SSL_CONTEXT_OPENTSDB: {
netdata_opentsdb_ctx = security_initialize_openssl_client();
break;
}
}
}
/**
* Clean Open SSL
*
* Clean all the allocated contexts from netdata.
*/
void security_clean_openssl() {
if (netdata_srv_ctx)
{
SSL_CTX_free(netdata_srv_ctx);
}
if (netdata_client_ctx)
{
SSL_CTX_free(netdata_client_ctx);
}
if ( netdata_opentsdb_ctx )
{
SSL_CTX_free(netdata_opentsdb_ctx);
}
#if OPENSSL_VERSION_NUMBER < OPENSSL_VERSION_110
ERR_free_strings();
#endif
}
/**
* Process accept
*
* Process the SSL handshake with the client case it is necessary.
*
* @param ssl is a pointer for the SSL structure
* @param msg is a copy of the first 8 bytes of the initial message received
*
* @return it returns 0 case it performs the handshake, 8 case it is clean connection
* and another integer power of 2 otherwise.
*/
int security_process_accept(SSL *ssl,int msg) {
int sock = SSL_get_fd(ssl);
int test;
if (msg > 0x17)
{
return NETDATA_SSL_NO_HANDSHAKE;
}
ERR_clear_error();
if ((test = SSL_accept(ssl)) <= 0) {
int sslerrno = SSL_get_error(ssl, test);
switch(sslerrno) {
case SSL_ERROR_WANT_READ:
{
error("SSL handshake did not finish and it wanna read on socket %d!", sock);
return NETDATA_SSL_WANT_READ;
}
case SSL_ERROR_WANT_WRITE:
{
error("SSL handshake did not finish and it wanna read on socket %d!", sock);
return NETDATA_SSL_WANT_WRITE;
}
case SSL_ERROR_NONE:
case SSL_ERROR_SSL:
case SSL_ERROR_SYSCALL:
default:
{
u_long err;
char buf[256];
int counter = 0;
while ((err = ERR_get_error()) != 0) {
ERR_error_string_n(err, buf, sizeof(buf));
info("%d SSL Handshake error (%s) on socket %d ", counter++, ERR_error_string((long)SSL_get_error(ssl, test), NULL), sock);
}
return NETDATA_SSL_NO_HANDSHAKE;
}
}
}
if (SSL_is_init_finished(ssl))
{
debug(D_WEB_CLIENT_ACCESS,"SSL Handshake finished %s errno %d on socket fd %d", ERR_error_string((long)SSL_get_error(ssl, test), NULL), errno, sock);
}
return NETDATA_SSL_HANDSHAKE_COMPLETE;
}
/**
* Test Certificate
*
* Check the certificate of Netdata parent
*
* @param ssl is the connection structure
*
* @return It returns 0 on success and -1 otherwise
*/
in
|