1 /*
2 Bacula(R) - The Network Backup Solution
3
4 Copyright (C) 2000-2020 Kern Sibbald
5
6 The original author of Bacula is Kern Sibbald, with contributions
7 from many others, a complete list can be found in the file AUTHORS.
8
9 You may use this file and others of this release according to the
10 license defined in the LICENSE file, which includes the Affero General
11 Public License, v3.0 ("AGPLv3") and some additional permissions and
12 terms pursuant to its AGPLv3 Section 7.
13
14 This notice must be preserved when any source code is
15 conveyed and/or propagated.
16
17 Bacula(R) is a registered trademark of Kern Sibbald.
18 */
19
20 /*
21 * Written by Eric Bollengier MMXVIII
22 */
23
24 /* Code to handle Bacula Client behind a NAT without a VPN
25 * We keep a connection idle with a short TCP keepalive to detect
26 * any problem very quickly.
27 *
28 * A thread can be responsible to listen all sockets and reply to
29 * a ISALIVE request. A ISALIVE request can be send after a wake up
30 * for example.
31 */
32
33 #include "bacula.h"
34 #include "bsock_meeting.h"
35
36 static int dbglvl = DT_NETWORK|50;
37
BsockMeeting()38 BsockMeeting::BsockMeeting(): socket(NULL), keepidle(0), keepintvl(0) {
39 pthread_mutex_init(&mutex, NULL);
40 pthread_cond_init(&cond, NULL);
41 };
42
~BsockMeeting()43 BsockMeeting::~BsockMeeting() {
44 pthread_mutex_destroy(&mutex);
45 pthread_cond_destroy(&cond);
46 free_bsock(socket);
47 };
48
set(BSOCK * s)49 void BsockMeeting::set(BSOCK *s) {
50 int turnon=1;
51 P(mutex);
52 free_bsock(socket); /* We are the owner of the socket object, we can use free */
53 socket = s;
54
55 /*
56 * Keep socket from timing out from inactivity
57 */
58 if (setsockopt(socket->m_fd, SOL_SOCKET, SO_KEEPALIVE, (sockopt_val_t)&turnon, sizeof(turnon)) < 0) {
59 berrno be;
60 Dmsg1(dbglvl, _("Cannot set SO_KEEPALIVE on socket: %s\n"), be.bstrerror());
61 }
62 #if defined(TCP_KEEPIDLE)
63 if (getsockopt(socket->m_fd, SOL_TCP, TCP_KEEPIDLE, (sockopt_val_t)&keepidle, sizeof(keepidle)) < 0) {
64 berrno be;
65 Dmsg1(dbglvl, _("Cannot get TCP_KEEPIDLE on socket: %s\n"), be.bstrerror());
66 }
67 opt = 10000;
68 if (setsockopt(socket->m_fd, SOL_TCP, TCP_KEEPIDLE, (sockopt_val_t)&opt, sizeof(opt)) < 0) {
69 berrno be;
70 Dmsg1(dbglvl, _("Cannot set TCP_KEEPIDLE on socket: %s\n"), be.bstrerror());
71 }
72 #endif
73 #if defined(TCP_KEEPINTVL)
74 if (getsockopt(socket->m_fd, SOL_TCP, TCP_KEEPINTVL, (sockopt_val_t)&keepintvl, sizeof(keepintvl)) < 0) {
75 berrno be;
76 Dmsg1(dbglvl, _("Cannot get TCP_KEEPINTVL on socket: %s\n"), be.bstrerror());
77 }
78 opt = 5000;
79 if (setsockopt(socket->m_fd, SOL_TCP, TCP_KEEPINTVL, (sockopt_val_t)&opt, sizeof(opt)) < 0) {
80 berrno be;
81 Dmsg1(dbglvl, _("Cannot set TCP_KEEPINTVL on socket: %s\n"), be.bstrerror());
82 }
83 #endif
84 pthread_cond_signal(&cond);
85 V(mutex);
86 };
87
88 /* Get the current Socket, wait timeout to get it */
get(int timeout)89 BSOCK *BsockMeeting::get(int timeout) {
90 BSOCK *ret=NULL;
91 struct timespec to;
92 btimer_t *t;
93 int32_t sig=0;
94
95 P(mutex);
96 to.tv_sec = time(NULL) + timeout;
97 to.tv_nsec = 0;
98 while (socket == NULL) {
99 Dmsg0(dbglvl, "socket is null...\n");
100 int err = pthread_cond_timedwait(&cond, &mutex, &to);
101 if (err == ETIMEDOUT) {
102 Dmsg0(dbglvl, "Timeout\n");
103 /* timeout, do something */
104 break;
105 } else {
106 Dmsg2(dbglvl, "timedwait=%d socket=%p\n", err, socket);
107 }
108 }
109 /* TODO: We need to test if the socket is still valid, and we need a read() to raise
110 * an error. We don't want to give a broken socket to the job
111 */
112 if (socket) {
113 Dmsg0(dbglvl, "Found a socket in the proxy\n");
114 t = start_bsock_timer(socket, 10);
115 socket->signal(BNET_ISALIVE);
116 sig = socket->recv();
117 stop_bsock_timer(t);
118
119 if (sig != -1 || socket->msglen != BNET_ISALIVE) {
120 Dmsg2(dbglvl, "Socket seems broken sig=%d msglen=%d\n", sig, socket->msglen);
121 free_bsock(socket);
122 V(mutex); /* Let's get a new one */
123 return get(timeout);
124 }
125 Dmsg0(dbglvl, "Socket seems OK\n");
126 }
127 if (socket) {
128 #if defined(TCP_KEEPIDLE)
129 if (setsockopt(socket->m_fd, SOL_TCP, TCP_KEEPIDLE, (sockopt_val_t)&keepidle, sizeof(keepidle)) < 0) {
130 berrno be;
131 Dmsg1(dbglvl, _("Cannot set TCP_KEEPIDLE on socket: %s\n"), be.bstrerror());
132 }
133 #endif
134 #if defined(TCP_KEEPINTVL)
135 if (setsockopt(socket->m_fd, SOL_TCP, TCP_KEEPINTVL, (sockopt_val_t)&keepintvl, sizeof(keepintvl)) < 0) {
136 berrno be;
137 Dmsg1(dbglvl, _("Cannot set TCP_KEEPINTVL on socket: %s\n"), be.bstrerror());
138 }
139 #endif
140 }
141 ret = socket;
142 socket = NULL;
143 V(mutex);
144 return ret;
145 };
146
is_set(POOLMEM * & address)147 bool BsockMeeting::is_set(POOLMEM *&address)
148 {
149 lock_guard g(mutex);
150 if (address) {
151 *address = 0;
152 }
153 if (!socket) {
154 return false;
155 }
156 if (address) {
157 pm_strcpy(address, socket->host());
158 }
159 return true;
160 }
161
wait_request(BSOCK * dir)162 void BsockMeeting::wait_request(BSOCK *dir) {
163 int32_t sig = dir->recv();
164 if (sig == -1 && dir->msglen == BNET_ISALIVE) {
165 /* nop */
166 dir->signal(BNET_ISALIVE);
167 } else {
168 Dmsg1(dbglvl, "got incorrect message sig=%d\n", sig);
169 dir->close();
170 }
171 };
172