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autorid: introduce idmap_autorid_domsid_is_for_alloc()
[Samba.git] / ctdb / common / system_linux.c
blob9aaa1fdd7cea8ab25d292e70f435e4432a65b71e
1 /*
2 ctdb system specific code to manage raw sockets on linux
3
4 Copyright (C) Ronnie Sahlberg 2007
5 Copyright (C) Andrew Tridgell 2007
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "includes.h"
22 #include "system/network.h"
23 #include "system/filesys.h"
24 #include "system/wait.h"
25 #include "../include/ctdb_private.h"
26 #include <netinet/if_ether.h>
27 #include <netinet/ip6.h>
28 #include <netinet/icmp6.h>
29 #include <net/if_arp.h>
30 #include <netpacket/packet.h>
31 #include <sys/prctl.h>
32
33 #ifndef ETHERTYPE_IP6
34 #define ETHERTYPE_IP6 0x86dd
35 #endif
36
37 /*
38 calculate the tcp checksum for tcp over ipv6
39 */
40 static uint16_t tcp_checksum6(uint16_t *data, size_t n, struct ip6_hdr *ip6)
41 {
42 uint32_t phdr[2];
43 uint32_t sum = 0;
44 uint16_t sum2;
45
46 sum += uint16_checksum((uint16_t *)(void *)&ip6->ip6_src, 16);
47 sum += uint16_checksum((uint16_t *)(void *)&ip6->ip6_dst, 16);
48
49 phdr[0] = htonl(n);
50 phdr[1] = htonl(ip6->ip6_nxt);
51 sum += uint16_checksum((uint16_t *)phdr, 8);
52
53 sum += uint16_checksum(data, n);
54
55 sum = (sum & 0xFFFF) + (sum >> 16);
56 sum = (sum & 0xFFFF) + (sum >> 16);
57 sum2 = htons(sum);
58 sum2 = ~sum2;
59 if (sum2 == 0) {
60 return 0xFFFF;
61 }
62 return sum2;
63 }
64
65 /*
66 send gratuitous arp reply after we have taken over an ip address
67
68 saddr is the address we are trying to claim
69 iface is the interface name we will be using to claim the address
70 */
71 int ctdb_sys_send_arp(const ctdb_sock_addr *addr, const char *iface)
72 {
73 int s, ret;
74 struct sockaddr_ll sall;
75 struct ether_header *eh;
76 struct arphdr *ah;
77 struct ip6_hdr *ip6;
78 struct nd_neighbor_solicit *nd_ns;
79 struct ifreq if_hwaddr;
80 unsigned char buffer[78]; /* ipv6 neigh solicitation size */
81 char *ptr;
82 char bdcast[] = {0xff,0xff,0xff,0xff,0xff,0xff};
83 struct ifreq ifr;
84
85 ZERO_STRUCT(sall);
86 ZERO_STRUCT(ifr);
87 ZERO_STRUCT(if_hwaddr);
88
89 switch (addr->ip.sin_family) {
90 case AF_INET:
91 s = socket(PF_PACKET, SOCK_RAW, htons(ETHERTYPE_ARP));
92 if (s == -1){
93 DEBUG(DEBUG_CRIT,(__location__ " failed to open raw socket\n"));
94 return -1;
95 }
96
97 DEBUG(DEBUG_DEBUG, (__location__ " Created SOCKET FD:%d for sending arp\n", s));
98 strncpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name)-1);
99 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
100 DEBUG(DEBUG_CRIT,(__location__ " interface '%s' not found\n", iface));
101 close(s);
102 return -1;
103 }
104
105 /* get the mac address */
106 strncpy(if_hwaddr.ifr_name, iface, sizeof(if_hwaddr.ifr_name)-1);
107 ret = ioctl(s, SIOCGIFHWADDR, &if_hwaddr);
108 if ( ret < 0 ) {
109 close(s);
110 DEBUG(DEBUG_CRIT,(__location__ " ioctl failed\n"));
111 return -1;
112 }
113 if (ARPHRD_LOOPBACK == if_hwaddr.ifr_hwaddr.sa_family) {
114 DEBUG(DEBUG_DEBUG,("Ignoring loopback arp request\n"));
115 close(s);
116 return 0;
117 }
118 if (if_hwaddr.ifr_hwaddr.sa_family != AF_LOCAL) {
119 close(s);
120 errno = EINVAL;
121 DEBUG(DEBUG_CRIT,(__location__ " not an ethernet address family (0x%x)\n",
122 if_hwaddr.ifr_hwaddr.sa_family));
123 return -1;
124 }
125
126
127 memset(buffer, 0 , 64);
128 eh = (struct ether_header *)buffer;
129 memset(eh->ether_dhost, 0xff, ETH_ALEN);
130 memcpy(eh->ether_shost, if_hwaddr.ifr_hwaddr.sa_data, ETH_ALEN);
131 eh->ether_type = htons(ETHERTYPE_ARP);
132
133 ah = (struct arphdr *)&buffer[sizeof(struct ether_header)];
134 ah->ar_hrd = htons(ARPHRD_ETHER);
135 ah->ar_pro = htons(ETH_P_IP);
136 ah->ar_hln = ETH_ALEN;
137 ah->ar_pln = 4;
138
139 /* send a gratious arp */
140 ah->ar_op = htons(ARPOP_REQUEST);
141 ptr = (char *)&ah[1];
142 memcpy(ptr, if_hwaddr.ifr_hwaddr.sa_data, ETH_ALEN);
143 ptr+=ETH_ALEN;
144 memcpy(ptr, &addr->ip.sin_addr, 4);
145 ptr+=4;
146 memset(ptr, 0, ETH_ALEN);
147 ptr+=ETH_ALEN;
148 memcpy(ptr, &addr->ip.sin_addr, 4);
149 ptr+=4;
150
151 sall.sll_family = AF_PACKET;
152 sall.sll_halen = 6;
153 memcpy(&sall.sll_addr[0], bdcast, sall.sll_halen);
154 sall.sll_protocol = htons(ETH_P_ALL);
155 sall.sll_ifindex = ifr.ifr_ifindex;
156 ret = sendto(s, buffer, 64, 0, (struct sockaddr *)&sall, sizeof(sall));
157 if (ret < 0 ){
158 close(s);
159 DEBUG(DEBUG_CRIT,(__location__ " failed sendto\n"));
160 return -1;
161 }
162
163 /* send unsolicited arp reply broadcast */
164 ah->ar_op = htons(ARPOP_REPLY);
165 ptr = (char *)&ah[1];
166 memcpy(ptr, if_hwaddr.ifr_hwaddr.sa_data, ETH_ALEN);
167 ptr+=ETH_ALEN;
168 memcpy(ptr, &addr->ip.sin_addr, 4);
169 ptr+=4;
170 memcpy(ptr, if_hwaddr.ifr_hwaddr.sa_data, ETH_ALEN);
171 ptr+=ETH_ALEN;
172 memcpy(ptr, &addr->ip.sin_addr, 4);
173 ptr+=4;
174
175 ret = sendto(s, buffer, 64, 0, (struct sockaddr *)&sall, sizeof(sall));
176 if (ret < 0 ){
177 DEBUG(DEBUG_CRIT,(__location__ " failed sendto\n"));
178 close(s);
179 return -1;
180 }
181
182 close(s);
183 break;
184 case AF_INET6:
185 s = socket(PF_PACKET, SOCK_RAW, htons(ETHERTYPE_ARP));
186 if (s == -1){
187 DEBUG(DEBUG_CRIT,(__location__ " failed to open raw socket\n"));
188 return -1;
189 }
190
191 DEBUG(DEBUG_DEBUG, (__location__ " Created SOCKET FD:%d for sending arp\n", s));
192 strncpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name));
193 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
194 DEBUG(DEBUG_CRIT,(__location__ " interface '%s' not found\n", iface));
195 close(s);
196 return -1;
197 }
198
199 /* get the mac address */
200 strncpy(if_hwaddr.ifr_name, iface, sizeof(if_hwaddr.ifr_name)-1);
201 ret = ioctl(s, SIOCGIFHWADDR, &if_hwaddr);
202 if ( ret < 0 ) {
203 close(s);
204 DEBUG(DEBUG_CRIT,(__location__ " ioctl failed\n"));
205 return -1;
206 }
207 if (ARPHRD_LOOPBACK == if_hwaddr.ifr_hwaddr.sa_family) {
208 DEBUG(DEBUG_DEBUG,("Ignoring loopback arp request\n"));
209 close(s);
210 return 0;
211 }
212 if (if_hwaddr.ifr_hwaddr.sa_family != AF_LOCAL) {
213 close(s);
214 errno = EINVAL;
215 DEBUG(DEBUG_CRIT,(__location__ " not an ethernet address family (0x%x)\n",
216 if_hwaddr.ifr_hwaddr.sa_family));
217 return -1;
218 }
219
220 memset(buffer, 0 , sizeof(buffer));
221 eh = (struct ether_header *)buffer;
222 memset(eh->ether_dhost, 0xff, ETH_ALEN);
223 memcpy(eh->ether_shost, if_hwaddr.ifr_hwaddr.sa_data, ETH_ALEN);
224 eh->ether_type = htons(ETHERTYPE_IP6);
225
226 ip6 = (struct ip6_hdr *)(eh+1);
227 ip6->ip6_vfc = 0x60;
228 ip6->ip6_plen = htons(sizeof(*nd_ns));
229 ip6->ip6_nxt = IPPROTO_ICMPV6;
230 ip6->ip6_hlim = 255;
231 ip6->ip6_dst = addr->ip6.sin6_addr;
232
233 nd_ns = (struct nd_neighbor_solicit *)(ip6+1);
234 nd_ns->nd_ns_type = ND_NEIGHBOR_SOLICIT;
235 nd_ns->nd_ns_code = 0;
236 nd_ns->nd_ns_reserved = 0;
237 nd_ns->nd_ns_target = addr->ip6.sin6_addr;
238
239 nd_ns->nd_ns_cksum = tcp_checksum6((uint16_t *)nd_ns, ntohs(ip6->ip6_plen), ip6);
240
241 sall.sll_family = AF_PACKET;
242 sall.sll_halen = 6;
243 memcpy(&sall.sll_addr[0], bdcast, sall.sll_halen);
244 sall.sll_protocol = htons(ETH_P_ALL);
245 sall.sll_ifindex = ifr.ifr_ifindex;
246 ret = sendto(s, buffer, 78, 0, (struct sockaddr *)&sall, sizeof(sall));
247 if (ret < 0 ){
248 close(s);
249 DEBUG(DEBUG_CRIT,(__location__ " failed sendto\n"));
250 return -1;
251 }
252
253 close(s);
254 break;
255 default:
256 DEBUG(DEBUG_CRIT,(__location__ " not an ipv4/ipv6 address (family is %u)\n", addr->ip.sin_family));
257 return -1;
258 }
259
260 return 0;
261 }
262
263
264 /*
265 simple TCP checksum - assumes data is multiple of 2 bytes long
266 */
267 static uint16_t tcp_checksum(uint16_t *data, size_t n, struct iphdr *ip)
268 {
269 uint32_t sum = uint16_checksum(data, n);
270 uint16_t sum2;
271 sum += uint16_checksum((uint16_t *)(void *)&ip->saddr,
272 sizeof(ip->saddr));
273 sum += uint16_checksum((uint16_t *)(void *)&ip->daddr,
274 sizeof(ip->daddr));
275 sum += ip->protocol + n;
276 sum = (sum & 0xFFFF) + (sum >> 16);
277 sum = (sum & 0xFFFF) + (sum >> 16);
278 sum2 = htons(sum);
279 sum2 = ~sum2;
280 if (sum2 == 0) {
281 return 0xFFFF;
282 }
283 return sum2;
284 }
285
286 /*
287 Send tcp segment from the specified IP/port to the specified
288 destination IP/port.
289
290 This is used to trigger the receiving host into sending its own ACK,
291 which should trigger early detection of TCP reset by the client
292 after IP takeover
293
294 This can also be used to send RST segments (if rst is true) and also
295 if correct seq and ack numbers are provided.
296 */
297 int ctdb_sys_send_tcp(const ctdb_sock_addr *dest,
298 const ctdb_sock_addr *src,
299 uint32_t seq, uint32_t ack, int rst)
300 {
301 int s;
302 int ret;
303 uint32_t one = 1;
304 uint16_t tmpport;
305 ctdb_sock_addr *tmpdest;
306 struct {
307 struct iphdr ip;
308 struct tcphdr tcp;
309 } ip4pkt;
310 struct {
311 struct ip6_hdr ip6;
312 struct tcphdr tcp;
313 } ip6pkt;
314
315 switch (src->ip.sin_family) {
316 case AF_INET:
317 ZERO_STRUCT(ip4pkt);
318 ip4pkt.ip.version = 4;
319 ip4pkt.ip.ihl = sizeof(ip4pkt.ip)/4;
320 ip4pkt.ip.tot_len = htons(sizeof(ip4pkt));
321 ip4pkt.ip.ttl = 255;
322 ip4pkt.ip.protocol = IPPROTO_TCP;
323 ip4pkt.ip.saddr = src->ip.sin_addr.s_addr;
324 ip4pkt.ip.daddr = dest->ip.sin_addr.s_addr;
325 ip4pkt.ip.check = 0;
326
327 ip4pkt.tcp.source = src->ip.sin_port;
328 ip4pkt.tcp.dest = dest->ip.sin_port;
329 ip4pkt.tcp.seq = seq;
330 ip4pkt.tcp.ack_seq = ack;
331 ip4pkt.tcp.ack = 1;
332 if (rst) {
333 ip4pkt.tcp.rst = 1;
334 }
335 ip4pkt.tcp.doff = sizeof(ip4pkt.tcp)/4;
336 /* this makes it easier to spot in a sniffer */
337 ip4pkt.tcp.window = htons(1234);
338 ip4pkt.tcp.check = tcp_checksum((uint16_t *)&ip4pkt.tcp, sizeof(ip4pkt.tcp), &ip4pkt.ip);
339
340 /* open a raw socket to send this segment from */
341 s = socket(AF_INET, SOCK_RAW, htons(IPPROTO_RAW));
342 if (s == -1) {
343 DEBUG(DEBUG_CRIT,(__location__ " failed to open raw socket (%s)\n",
344 strerror(errno)));
345 return -1;
346 }
347
348 ret = setsockopt(s, SOL_IP, IP_HDRINCL, &one, sizeof(one));
349 if (ret != 0) {
350 DEBUG(DEBUG_CRIT,(__location__ " failed to setup IP headers (%s)\n",
351 strerror(errno)));
352 close(s);
353 return -1;
354 }
355
356 set_nonblocking(s);
357 set_close_on_exec(s);
358
359 ret = sendto(s, &ip4pkt, sizeof(ip4pkt), 0,
360 (const struct sockaddr *)&dest->ip,
361 sizeof(dest->ip));
362 close(s);
363 if (ret != sizeof(ip4pkt)) {
364 DEBUG(DEBUG_CRIT,(__location__ " failed sendto (%s)\n", strerror(errno)));
365 return -1;
366 }
367 break;
368 case AF_INET6:
369 ZERO_STRUCT(ip6pkt);
370 ip6pkt.ip6.ip6_vfc = 0x60;
371 ip6pkt.ip6.ip6_plen = htons(20);
372 ip6pkt.ip6.ip6_nxt = IPPROTO_TCP;
373 ip6pkt.ip6.ip6_hlim = 64;
374 ip6pkt.ip6.ip6_src = src->ip6.sin6_addr;
375 ip6pkt.ip6.ip6_dst = dest->ip6.sin6_addr;
376
377 ip6pkt.tcp.source = src->ip6.sin6_port;
378 ip6pkt.tcp.dest = dest->ip6.sin6_port;
379 ip6pkt.tcp.seq = seq;
380 ip6pkt.tcp.ack_seq = ack;
381 ip6pkt.tcp.ack = 1;
382 if (rst) {
383 ip6pkt.tcp.rst = 1;
384 }
385 ip6pkt.tcp.doff = sizeof(ip6pkt.tcp)/4;
386 /* this makes it easier to spot in a sniffer */
387 ip6pkt.tcp.window = htons(1234);
388 ip6pkt.tcp.check = tcp_checksum6((uint16_t *)&ip6pkt.tcp, sizeof(ip6pkt.tcp), &ip6pkt.ip6);
389
390 s = socket(PF_INET6, SOCK_RAW, IPPROTO_RAW);
391 if (s == -1) {
392 DEBUG(DEBUG_CRIT, (__location__ " Failed to open sending socket\n"));
393 return -1;
394
395 }
396 /* sendto() dont like if the port is set and the socket is
397 in raw mode.
398 */
399 tmpdest = discard_const(dest);
400 tmpport = tmpdest->ip6.sin6_port;
401
402 tmpdest->ip6.sin6_port = 0;
403 ret = sendto(s, &ip6pkt, sizeof(ip6pkt), 0,
404 (const struct sockaddr *)&dest->ip6,
405 sizeof(dest->ip6));
406 tmpdest->ip6.sin6_port = tmpport;
407 close(s);
408
409 if (ret != sizeof(ip6pkt)) {
410 DEBUG(DEBUG_CRIT,(__location__ " failed sendto (%s)\n", strerror(errno)));
411 return -1;
412 }
413 break;
414
415 default:
416 DEBUG(DEBUG_CRIT,(__location__ " not an ipv4/v6 address\n"));
417 return -1;
418 }
419
420 return 0;
421 }
422
423 /*
424 This function is used to open a raw socket to capture from
425 */
426 int ctdb_sys_open_capture_socket(const char *iface, void **private_data)
427 {
428 int s;
429
430 /* Open a socket to capture all traffic */
431 s = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
432 if (s == -1) {
433 DEBUG(DEBUG_CRIT,(__location__ " failed to open raw socket\n"));
434 return -1;
435 }
436
437 DEBUG(DEBUG_DEBUG, (__location__ " Created RAW SOCKET FD:%d for tcp tickle\n", s));
438
439 set_nonblocking(s);
440 set_close_on_exec(s);
441
442 return s;
443 }
444
445 /*
446 This function is used to do any additional cleanup required when closing
447 a capture socket.
448 Note that the socket itself is closed automatically in the caller.
449 */
450 int ctdb_sys_close_capture_socket(void *private_data)
451 {
452 return 0;
453 }
454
455
456 /*
457 called when the raw socket becomes readable
458 */
459 int ctdb_sys_read_tcp_packet(int s, void *private_data,
460 ctdb_sock_addr *src, ctdb_sock_addr *dst,
461 uint32_t *ack_seq, uint32_t *seq)
462 {
463 int ret;
464 #define RCVPKTSIZE 100
465 char pkt[RCVPKTSIZE];
466 struct ether_header *eth;
467 struct iphdr *ip;
468 struct ip6_hdr *ip6;
469 struct tcphdr *tcp;
470
471 ret = recv(s, pkt, RCVPKTSIZE, MSG_TRUNC);
472 if (ret < sizeof(*eth)+sizeof(*ip)) {
473 return -1;
474 }
475
476 /* Ethernet */
477 eth = (struct ether_header *)pkt;
478
479 /* we want either IPv4 or IPv6 */
480 if (ntohs(eth->ether_type) == ETHERTYPE_IP) {
481 /* IP */
482 ip = (struct iphdr *)(eth+1);
483
484 /* We only want IPv4 packets */
485 if (ip->version != 4) {
486 return -1;
487 }
488 /* Dont look at fragments */
489 if ((ntohs(ip->frag_off)&0x1fff) != 0) {
490 return -1;
491 }
492 /* we only want TCP */
493 if (ip->protocol != IPPROTO_TCP) {
494 return -1;
495 }
496
497 /* make sure its not a short packet */
498 if (offsetof(struct tcphdr, ack_seq) + 4 +
499 (ip->ihl*4) + sizeof(*eth) > ret) {
500 return -1;
501 }
502 /* TCP */
503 tcp = (struct tcphdr *)((ip->ihl*4) + (char *)ip);
504
505 /* tell the caller which one we've found */
506 src->ip.sin_family = AF_INET;
507 src->ip.sin_addr.s_addr = ip->saddr;
508 src->ip.sin_port = tcp->source;
509 dst->ip.sin_family = AF_INET;
510 dst->ip.sin_addr.s_addr = ip->daddr;
511 dst->ip.sin_port = tcp->dest;
512 *ack_seq = tcp->ack_seq;
513 *seq = tcp->seq;
514
515 return 0;
516 } else if (ntohs(eth->ether_type) == ETHERTYPE_IP6) {
517 /* IP6 */
518 ip6 = (struct ip6_hdr *)(eth+1);
519
520 /* we only want TCP */
521 if (ip6->ip6_nxt != IPPROTO_TCP) {
522 return -1;
523 }
524
525 /* TCP */
526 tcp = (struct tcphdr *)(ip6+1);
527
528 /* tell the caller which one we've found */
529 src->ip6.sin6_family = AF_INET6;
530 src->ip6.sin6_port = tcp->source;
531 src->ip6.sin6_addr = ip6->ip6_src;
532
533 dst->ip6.sin6_family = AF_INET6;
534 dst->ip6.sin6_port = tcp->dest;
535 dst->ip6.sin6_addr = ip6->ip6_dst;
536
537 *ack_seq = tcp->ack_seq;
538 *seq = tcp->seq;
539
540 return 0;
541 }
542
543 return -1;
544 }
545
546
547 bool ctdb_sys_check_iface_exists(const char *iface)
548 {
549 int s;
550 struct ifreq ifr;
551
552 s = socket(PF_PACKET, SOCK_RAW, 0);
553 if (s == -1){
554 /* We dont know if the interface exists, so assume yes */
555 DEBUG(DEBUG_CRIT,(__location__ " failed to open raw socket\n"));
556 return true;
557 }
558
559 strncpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name)-1);
560 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0 && errno == ENODEV) {
561 DEBUG(DEBUG_CRIT,(__location__ " interface '%s' not found\n", iface));
562 close(s);
563 return false;
564 }
565 close(s);
566
567 return true;
568 }
569
570 int ctdb_get_peer_pid(const int fd, pid_t *peer_pid)
571 {
572 struct ucred cr;
573 socklen_t crl = sizeof(struct ucred);
574 int ret;
575 if ((ret = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &cr, &crl) == 0)) {
576 *peer_pid = cr.pid;
577 }
578 return ret;
579 }
580
581 /*
582 * Find the process name from process ID
583 */
584 char *ctdb_get_process_name(pid_t pid)
585 {
586 char path[32];
587 char buf[PATH_MAX];
588 char *ptr;
589 int n;
590
591 snprintf(path, sizeof(path), "/proc/%d/exe", pid);
592 n = readlink(path, buf, sizeof(buf)-1);
593 if (n < 0) {
594 return NULL;
595 }
596
597 /* Remove any extra fields */
598 buf[n] = '\0';
599 ptr = strtok(buf, " ");
600 return (ptr == NULL ? ptr : strdup(ptr));
601 }
602
603 /*
604 * Set process name
605 */
606 int ctdb_set_process_name(const char *name)
607 {
608 char procname[16];
609
610 strncpy(procname, name, 15);
611 procname[15] = '\0';
612 return prctl(PR_SET_NAME, (unsigned long)procname, 0, 0, 0);
613 }
614
615 /*
616 * Parsing a line from /proc/locks,
617 */
618 static bool parse_proc_locks_line(char *line, pid_t *pid,
619 struct ctdb_lock_info *curlock)
620 {
621 char *ptr, *saveptr;
622
623 /* output of /proc/locks
624 *
625 * lock assigned
626 * 1: POSIX ADVISORY WRITE 25945 fd:00:6424820 212 212
627 *
628 * lock waiting
629 * 1: -> POSIX ADVISORY WRITE 25946 fd:00:6424820 212 212
630 */
631
632 /* Id: */
633 ptr = strtok_r(line, " ", &saveptr);
634 if (ptr == NULL) return false;
635
636 /* -> */
637 ptr = strtok_r(NULL, " ", &saveptr);
638 if (ptr == NULL) return false;
639 if (strcmp(ptr, "->") == 0) {
640 curlock->waiting = true;
641 ptr = strtok_r(NULL, " ", &saveptr);
642 } else {
643 curlock->waiting = false;
644 }
645
646 /* POSIX */
647 if (ptr == NULL || strcmp(ptr, "POSIX") != 0) {
648 return false;
649 }
650
651 /* ADVISORY */
652 ptr = strtok_r(NULL, " ", &saveptr);
653 if (ptr == NULL) return false;
654
655 /* WRITE */
656 ptr = strtok_r(NULL, " ", &saveptr);
657 if (ptr == NULL) return false;
658 if (strcmp(ptr, "READ") == 0) {
659 curlock->read_only = true;
660 } else if (strcmp(ptr, "WRITE") == 0) {
661 curlock->read_only = false;
662 } else {
663 return false;
664 }
665
666 /* PID */
667 ptr = strtok_r(NULL, " ", &saveptr);
668 if (ptr == NULL) return false;
669 *pid = atoi(ptr);
670
671 /* MAJOR:MINOR:INODE */
672 ptr = strtok_r(NULL, " :", &saveptr);
673 if (ptr == NULL) return false;
674 ptr = strtok_r(NULL, " :", &saveptr);
675 if (ptr == NULL) return false;
676 ptr = strtok_r(NULL, " :", &saveptr);
677 if (ptr == NULL) return false;
678 curlock->inode = atol(ptr);
679
680 /* START OFFSET */
681 ptr = strtok_r(NULL, " ", &saveptr);
682 if (ptr == NULL) return false;
683 curlock->start = atol(ptr);
684
685 /* END OFFSET */
686 ptr = strtok_r(NULL, " ", &saveptr);
687 if (ptr == NULL) return false;
688 if (strncmp(ptr, "EOF", 3) == 0) {
689 curlock->end = (off_t)-1;
690 } else {
691 curlock->end = atol(ptr);
692 }
693
694 return true;
695 }
696
697 /*
698 * Find information of lock being waited on for given process ID
699 */
700 bool ctdb_get_lock_info(pid_t req_pid, struct ctdb_lock_info *lock_info)
701 {
702 FILE *fp;
703 struct ctdb_lock_info curlock;
704 pid_t pid;
705 char buf[1024];
706 bool status = false;
707
708 if ((fp = fopen("/proc/locks", "r")) == NULL) {
709 DEBUG(DEBUG_ERR, ("Failed to read locks information"));
710 return false;
711 }
712 while (fgets(buf, sizeof(buf), fp) != NULL) {
713 if (! parse_proc_locks_line(buf, &pid, &curlock)) {
714 continue;
715 }
716 if (pid == req_pid && curlock.waiting) {
717 *lock_info = curlock;
718 status = true;
719 break;
720 }
721 }
722 fclose(fp);
723
724 return status;
725 }
726
727 /*
728 * Find process ID which holds an overlapping byte lock for required
729 * inode and byte range.
730 */
731 bool ctdb_get_blocker_pid(struct ctdb_lock_info *reqlock, pid_t *blocker_pid)
732 {
733 FILE *fp;
734 struct ctdb_lock_info curlock;
735 pid_t pid;
736 char buf[1024];
737 bool status = false;
738
739 if ((fp = fopen("/proc/locks", "r")) == NULL) {
740 DEBUG(DEBUG_ERR, ("Failed to read locks information"));
741 return false;
742 }
743 while (fgets(buf, sizeof(buf), fp) != NULL) {
744 if (! parse_proc_locks_line(buf, &pid, &curlock)) {
745 continue;
746 }
747
748 if (curlock.waiting) {
749 continue;
750 }
751
752 if (curlock.inode != reqlock->inode) {
753 continue;
754 }
755
756 if (curlock.start > reqlock->end ||
757 curlock.end < reqlock->start) {
758 /* Outside the required range */
759 continue;
760 }
761 *blocker_pid = pid;
762 status = true;
763 break;
764 }
765 fclose(fp);
766
767 return status;
768 }
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