m_action.c revision b159a7f1aeb4c2fc3a9053d314bbc4d235beac67 
1/*
2 * m_action.c		Action Management
3 *
4 *		This program is free software; you can distribute it and/or
5 *		modify it under the terms of the GNU General Public License
6 *		as published by the Free Software Foundation; either version
7 *		2 of the License, or (at your option) any later version.
8 *
9 * Authors:  J Hadi Salim (hadi@cyberus.ca)
10 *
11 * TODO:
12 * - parse to be passed a filedescriptor for logging purposes
13 *
14*/
15
16#include <stdio.h>
17#include <stdlib.h>
18#include <unistd.h>
19#include <syslog.h>
20#include <fcntl.h>
21#include <sys/socket.h>
22#include <netinet/in.h>
23#include <arpa/inet.h>
24#include <string.h>
25#include <dlfcn.h>
26
27#include "utils.h"
28#include "tc_common.h"
29#include "tc_util.h"
30
31static struct action_util * action_list;
32#ifdef CONFIG_GACT
33int gact_ld = 0 ; //fuckin backward compatibility
34#endif
35int batch_c = 0;
36int tab_flush = 0;
37
38static void act_usage(void)
39{
40	/*XXX: In the near future add a action->print_help to improve
41	 * usability
42	 * This would mean new tc will not be backward compatible
43	 * with any action .so from the old days. But if someone really
44	 * does that, they would know how to fix this ..
45	 *
46	*/
47	fprintf (stderr, "usage: tc actions <ACTSPECOP>*\n");
48	fprintf(stderr,
49		"Where: \tACTSPECOP := ACR | GD | FL\n"
50			"\tACR := add | change | replace <ACTSPEC>* \n"
51			"\tGD := get | delete | <ACTISPEC>*\n"
52			"\tFL := ls | list | flush | <ACTNAMESPEC>\n"
53			"\tACTNAMESPEC :=  action <ACTNAME>\n"
54			"\tACTISPEC := <ACTNAMESPEC> <INDEXSPEC>\n"
55			"\tACTSPEC := action <ACTDETAIL> [INDEXSPEC]\n"
56			"\tINDEXSPEC := index <32 bit indexvalue>\n"
57			"\tACTDETAIL := <ACTNAME> <ACTPARAMS>\n"
58			"\t\tExample ACTNAME is gact, mirred etc\n"
59			"\t\tEach action has its own parameters (ACTPARAMS)\n"
60			"\n");
61
62	exit(-1);
63}
64
65static int print_noaopt(struct action_util *au, FILE *f, struct rtattr *opt)
66{
67	if (opt && RTA_PAYLOAD(opt))
68		fprintf(f, "[Unknown action, optlen=%u] ",
69			(unsigned) RTA_PAYLOAD(opt));
70	return 0;
71}
72
73static int parse_noaopt(struct action_util *au, int *argc_p, char ***argv_p, int code, struct nlmsghdr *n)
74{
75	int argc = *argc_p;
76	char **argv = *argv_p;
77
78	if (argc) {
79		fprintf(stderr, "Unknown action \"%s\", hence option \"%s\" is unparsable\n", au->id, *argv);
80	} else {
81		fprintf(stderr, "Unknown action \"%s\"\n", au->id);
82	}
83	return -1;
84}
85
86static struct action_util *get_action_kind(char *str)
87{
88	static void *aBODY;
89	void *dlh;
90	char buf[256];
91	struct action_util *a;
92#ifdef CONFIG_GACT
93	int looked4gact = 0;
94restart_s:
95#endif
96	for (a = action_list; a; a = a->next) {
97		if (strcmp(a->id, str) == 0)
98			return a;
99	}
100
101	snprintf(buf, sizeof(buf), "%s/m_%s.so", get_tc_lib(), str);
102	dlh = dlopen(buf, RTLD_LAZY | RTLD_GLOBAL);
103	if (dlh == NULL) {
104		dlh = aBODY;
105		if (dlh == NULL) {
106			dlh = aBODY = dlopen(NULL, RTLD_LAZY);
107			if (dlh == NULL)
108				goto noexist;
109		}
110	}
111
112	snprintf(buf, sizeof(buf), "%s_action_util", str);
113	a = dlsym(dlh, buf);
114	if (a == NULL)
115		goto noexist;
116
117reg:
118	a->next = action_list;
119	action_list = a;
120	return a;
121
122noexist:
123#ifdef CONFIG_GACT
124	if (!looked4gact) {
125		looked4gact = 1;
126		strcpy(str,"gact");
127		goto restart_s;
128	}
129#endif
130	a = malloc(sizeof(*a));
131	if (a) {
132		memset(a, 0, sizeof(*a));
133		strncpy(a->id, "noact", 15);
134		a->parse_aopt = parse_noaopt;
135		a->print_aopt = print_noaopt;
136		goto reg;
137	}
138	return a;
139}
140
141static int
142new_cmd(char **argv)
143{
144	if ((matches(*argv, "change") == 0) ||
145		(matches(*argv, "replace") == 0)||
146		(matches(*argv, "delete") == 0)||
147		(matches(*argv, "get") == 0)||
148		(matches(*argv, "add") == 0))
149			return 1;
150
151	return 0;
152
153}
154
155int
156parse_action(int *argc_p, char ***argv_p, int tca_id, struct nlmsghdr *n)
157{
158	int argc = *argc_p;
159	char **argv = *argv_p;
160	struct rtattr *tail, *tail2;
161	char k[16];
162	int ok = 0;
163	int eap = 0; /* expect action parameters */
164
165	int ret = 0;
166	int prio = 0;
167
168	if (argc <= 0)
169		return -1;
170
171	tail = tail2 = NLMSG_TAIL(n);
172
173	addattr_l(n, MAX_MSG, tca_id, NULL, 0);
174
175	while (argc > 0) {
176
177		memset(k, 0, sizeof (k));
178
179		if (strcmp(*argv, "action") == 0 ) {
180			argc--;
181			argv++;
182			eap = 1;
183#ifdef CONFIG_GACT
184			if (!gact_ld) {
185				get_action_kind("gact");
186			}
187#endif
188			continue;
189		} else if (strcmp(*argv, "help") == 0) {
190			return -1;
191		} else if (new_cmd(argv)) {
192			goto done0;
193		} else {
194			struct action_util *a = NULL;
195			strncpy(k, *argv, sizeof (k) - 1);
196			eap = 0;
197			if (argc > 0 ) {
198				a = get_action_kind(k);
199			} else {
200done0:
201				if (ok)
202					break;
203				else
204					goto done;
205			}
206
207			if (NULL == a) {
208				goto bad_val;
209			}
210
211			tail = NLMSG_TAIL(n);
212			addattr_l(n, MAX_MSG, ++prio, NULL, 0);
213			addattr_l(n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
214
215			ret = a->parse_aopt(a,&argc, &argv, TCA_ACT_OPTIONS, n);
216
217			if (ret < 0) {
218				fprintf(stderr,"bad action parsing\n");
219				goto bad_val;
220			}
221			tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
222			ok++;
223		}
224
225	}
226
227	if (eap > 0) {
228		fprintf(stderr,"bad action empty %d\n",eap);
229		goto bad_val;
230	}
231
232	tail2->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail2;
233
234done:
235	*argc_p = argc;
236	*argv_p = argv;
237	return 0;
238bad_val:
239	/* no need to undo things, returning from here should
240	 * cause enough pain */
241	fprintf(stderr, "parse_action: bad value (%d:%s)!\n",argc,*argv);
242	return -1;
243}
244
245static int
246tc_print_one_action(FILE * f, struct rtattr *arg)
247{
248
249	struct rtattr *tb[TCA_ACT_MAX + 1];
250	int err = 0;
251	struct action_util *a = NULL;
252
253	if (arg == NULL)
254		return -1;
255
256	parse_rtattr_nested(tb, TCA_ACT_MAX, arg);
257	if (tb[TCA_ACT_KIND] == NULL) {
258		fprintf(stderr, "NULL Action!\n");
259		return -1;
260	}
261
262
263	a = get_action_kind(RTA_DATA(tb[TCA_ACT_KIND]));
264	if (NULL == a)
265		return err;
266
267	if (tab_flush) {
268		fprintf(f," %s \n", a->id);
269		tab_flush = 0;
270		return 0;
271	}
272
273	err = a->print_aopt(a,f,tb[TCA_ACT_OPTIONS]);
274
275
276	if (0 > err)
277		return err;
278
279	if (show_stats && tb[TCA_ACT_STATS]) {
280		fprintf(f, "\tAction statistics:\n");
281		print_tcstats2_attr(f, tb[TCA_ACT_STATS], "\t", NULL);
282		fprintf(f, "\n");
283	}
284
285	return 0;
286}
287
288int
289tc_print_action(FILE * f, const struct rtattr *arg)
290{
291
292	int i;
293	struct rtattr *tb[TCA_ACT_MAX_PRIO + 1];
294
295	if (arg == NULL)
296		return 0;
297
298	parse_rtattr_nested(tb, TCA_ACT_MAX_PRIO, arg);
299
300	if (tab_flush && NULL != tb[0]  && NULL == tb[1]) {
301		int ret = tc_print_one_action(f, tb[0]);
302		return ret;
303	}
304
305	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
306		if (tb[i]) {
307			fprintf(f, "\n\taction order %d: ", i + batch_c);
308			if (0 > tc_print_one_action(f, tb[i])) {
309				fprintf(f, "Error printing action\n");
310			}
311		}
312
313	}
314
315	batch_c+=TCA_ACT_MAX_PRIO ;
316	return 0;
317}
318
319int print_action(const struct sockaddr_nl *who,
320			   struct nlmsghdr *n,
321			   void *arg)
322{
323	FILE *fp = (FILE*)arg;
324	struct tcamsg *t = NLMSG_DATA(n);
325	int len = n->nlmsg_len;
326	struct rtattr * tb[TCAA_MAX+1];
327
328	len -= NLMSG_LENGTH(sizeof(*t));
329
330	if (len < 0) {
331		fprintf(stderr, "Wrong len %d\n", len);
332		return -1;
333	}
334
335	parse_rtattr(tb, TCAA_MAX, TA_RTA(t), len);
336
337	if (NULL == tb[TCA_ACT_TAB]) {
338		if (n->nlmsg_type != RTM_GETACTION)
339			fprintf(stderr, "print_action: NULL kind\n");
340		return -1;
341	}
342
343	if (n->nlmsg_type == RTM_DELACTION) {
344		if (n->nlmsg_flags & NLM_F_ROOT) {
345			fprintf(fp, "Flushed table ");
346			tab_flush = 1;
347		} else {
348			fprintf(fp, "deleted action ");
349		}
350	}
351
352	if (n->nlmsg_type == RTM_NEWACTION)
353		fprintf(fp, "Added action ");
354	tc_print_action(fp, tb[TCA_ACT_TAB]);
355
356	return 0;
357}
358
359static int tc_action_gd(int cmd, unsigned flags, int *argc_p, char ***argv_p)
360{
361	char k[16];
362	struct action_util *a = NULL;
363	int argc = *argc_p;
364	char **argv = *argv_p;
365	int prio = 0;
366	int ret = 0;
367	__u32 i;
368	struct sockaddr_nl nladdr;
369	struct rtattr *tail;
370	struct rtattr *tail2;
371	struct nlmsghdr *ans = NULL;
372
373	struct {
374		struct nlmsghdr         n;
375		struct tcamsg           t;
376		char                    buf[MAX_MSG];
377	} req;
378
379	req.t.tca_family = AF_UNSPEC;
380
381	memset(&req, 0, sizeof(req));
382
383	memset(&nladdr, 0, sizeof(nladdr));
384	nladdr.nl_family = AF_NETLINK;
385
386	req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
387	req.n.nlmsg_flags = NLM_F_REQUEST|flags;
388	req.n.nlmsg_type = cmd;
389	argc -=1;
390	argv +=1;
391
392
393	tail = NLMSG_TAIL(&req.n);
394	addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
395
396	while (argc > 0) {
397		if (strcmp(*argv, "action") == 0 ) {
398			argc--;
399			argv++;
400			continue;
401		} else if (strcmp(*argv, "help") == 0) {
402			return -1;
403		}
404
405		strncpy(k, *argv, sizeof (k) - 1);
406		a = get_action_kind(k);
407		if (NULL == a) {
408			fprintf(stderr, "Error: non existent action: %s\n",k);
409			ret = -1;
410			goto bad_val;
411		}
412		if (strcmp(a->id, k) != 0) {
413			fprintf(stderr, "Error: non existent action: %s\n",k);
414			ret = -1;
415			goto bad_val;
416		}
417
418		argc -=1;
419		argv +=1;
420		if (argc <= 0) {
421			fprintf(stderr, "Error: no index specified action: %s\n",k);
422			ret = -1;
423			goto bad_val;
424		}
425
426		if (matches(*argv, "index") == 0) {
427			NEXT_ARG();
428			if (get_u32(&i, *argv, 10)) {
429				fprintf(stderr, "Illegal \"index\"\n");
430				ret = -1;
431				goto bad_val;
432			}
433			argc -=1;
434			argv +=1;
435		} else {
436			fprintf(stderr, "Error: no index specified action: %s\n",k);
437			ret = -1;
438			goto bad_val;
439		}
440
441		tail2 = NLMSG_TAIL(&req.n);
442		addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
443		addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
444		addattr32(&req.n, MAX_MSG, TCA_ACT_INDEX, i);
445		tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
446
447	}
448
449	tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
450
451	req.n.nlmsg_seq = rth.dump = ++rth.seq;
452	if (cmd == RTM_GETACTION)
453		ans = &req.n;
454
455	if (rtnl_talk(&rth, &req.n, 0, 0, ans) < 0) {
456		fprintf(stderr, "We have an error talking to the kernel\n");
457		return 1;
458	}
459
460	if (ans && print_action(NULL, &req.n, (void*)stdout) < 0) {
461		fprintf(stderr, "Dump terminated\n");
462		return 1;
463	}
464
465	*argc_p = argc;
466	*argv_p = argv;
467bad_val:
468	return ret;
469}
470
471static int tc_action_modify(int cmd, unsigned flags, int *argc_p, char ***argv_p)
472{
473	int argc = *argc_p;
474	char **argv = *argv_p;
475	int ret = 0;
476
477	struct rtattr *tail;
478	struct {
479		struct nlmsghdr         n;
480		struct tcamsg           t;
481		char                    buf[MAX_MSG];
482	} req;
483
484	req.t.tca_family = AF_UNSPEC;
485
486	memset(&req, 0, sizeof(req));
487
488	req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
489	req.n.nlmsg_flags = NLM_F_REQUEST|flags;
490	req.n.nlmsg_type = cmd;
491	tail = NLMSG_TAIL(&req.n);
492	argc -=1;
493	argv +=1;
494	if (parse_action(&argc, &argv, TCA_ACT_TAB, &req.n)) {
495		fprintf(stderr, "Illegal \"action\"\n");
496		return -1;
497	}
498	tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
499
500	if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0) {
501		fprintf(stderr, "We have an error talking to the kernel\n");
502		ret = -1;
503	}
504
505	*argc_p = argc;
506	*argv_p = argv;
507
508	return ret;
509}
510
511static int tc_act_list_or_flush(int argc, char **argv, int event)
512{
513	int ret = 0, prio = 0, msg_size = 0;
514	char k[16];
515	struct rtattr *tail,*tail2;
516	struct action_util *a = NULL;
517	struct {
518		struct nlmsghdr         n;
519		struct tcamsg           t;
520		char                    buf[MAX_MSG];
521	} req;
522
523	req.t.tca_family = AF_UNSPEC;
524
525	memset(&req, 0, sizeof(req));
526
527	req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
528
529	tail = NLMSG_TAIL(&req.n);
530	addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
531	tail2 = NLMSG_TAIL(&req.n);
532
533	strncpy(k, *argv, sizeof (k) - 1);
534#ifdef CONFIG_GACT
535	if (!gact_ld) {
536		get_action_kind("gact");
537	}
538#endif
539	a = get_action_kind(k);
540	if (NULL == a) {
541		fprintf(stderr,"bad action %s\n",k);
542		goto bad_val;
543	}
544	if (strcmp(a->id, k) != 0) {
545		fprintf(stderr,"bad action %s\n",k);
546		goto bad_val;
547	}
548	strncpy(k, *argv, sizeof (k) - 1);
549
550	addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
551	addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
552	tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
553	tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
554
555	msg_size = NLMSG_ALIGN(req.n.nlmsg_len) - NLMSG_ALIGN(sizeof(struct nlmsghdr));
556
557	if (event == RTM_GETACTION) {
558		if (rtnl_dump_request(&rth, event, (void *)&req.t, msg_size) < 0) {
559			perror("Cannot send dump request");
560			return 1;
561		}
562		ret = rtnl_dump_filter(&rth, print_action, stdout);
563	}
564
565	if (event == RTM_DELACTION) {
566		req.n.nlmsg_len = NLMSG_ALIGN(req.n.nlmsg_len);
567		req.n.nlmsg_type = RTM_DELACTION;
568		req.n.nlmsg_flags |= NLM_F_ROOT;
569		req.n.nlmsg_flags |= NLM_F_REQUEST;
570		if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0) {
571			fprintf(stderr, "We have an error flushing\n");
572			return 1;
573		}
574
575	}
576
577bad_val:
578
579	return ret;
580}
581
582int do_action(int argc, char **argv)
583{
584
585	int ret = 0;
586
587	while (argc > 0) {
588
589		if (matches(*argv, "add") == 0) {
590			ret =  tc_action_modify(RTM_NEWACTION, NLM_F_EXCL|NLM_F_CREATE, &argc, &argv);
591		} else if (matches(*argv, "change") == 0 ||
592			  matches(*argv, "replace") == 0) {
593			ret = tc_action_modify(RTM_NEWACTION, NLM_F_CREATE|NLM_F_REPLACE, &argc, &argv);
594		} else if (matches(*argv, "delete") == 0) {
595			argc -=1;
596			argv +=1;
597			ret = tc_action_gd(RTM_DELACTION, 0,  &argc, &argv);
598		} else if (matches(*argv, "get") == 0) {
599			argc -=1;
600			argv +=1;
601			ret = tc_action_gd(RTM_GETACTION, 0,  &argc, &argv);
602		} else if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
603						|| matches(*argv, "lst") == 0) {
604			if (argc <= 2) {
605				act_usage();
606				return -1;
607			}
608			return tc_act_list_or_flush(argc-2, argv+2, RTM_GETACTION);
609		} else if (matches(*argv, "flush") == 0) {
610			if (argc <= 2) {
611				act_usage();
612				return -1;
613			}
614			return tc_act_list_or_flush(argc-2, argv+2, RTM_DELACTION);
615		} else if (matches(*argv, "help") == 0) {
616			act_usage();
617			return -1;
618		} else {
619
620			ret = -1;
621		}
622
623		if (ret < 0) {
624			fprintf(stderr, "Command \"%s\" is unknown, try \"tc actions help\".\n", *argv);
625			return -1;
626		}
627	}
628
629	return 0;
630}
631
632