network.c revision 059d84dbb3897d4ee494a9c842c5dda54316cb47
1/*
2 * security/tomoyo/network.c
3 *
4 * Copyright (C) 2005-2011  NTT DATA CORPORATION
5 */
6
7#include "common.h"
8#include <linux/slab.h>
9
10/* Structure for holding inet domain socket's address. */
11struct tomoyo_inet_addr_info {
12	__be16 port;           /* In network byte order. */
13	const __be32 *address; /* In network byte order. */
14	bool is_ipv6;
15};
16
17/* Structure for holding unix domain socket's address. */
18struct tomoyo_unix_addr_info {
19	u8 *addr; /* This may not be '\0' terminated string. */
20	unsigned int addr_len;
21};
22
23/* Structure for holding socket address. */
24struct tomoyo_addr_info {
25	u8 protocol;
26	u8 operation;
27	struct tomoyo_inet_addr_info inet;
28	struct tomoyo_unix_addr_info unix0;
29};
30
31/* String table for socket's protocols. */
32const char * const tomoyo_proto_keyword[TOMOYO_SOCK_MAX] = {
33	[SOCK_STREAM]    = "stream",
34	[SOCK_DGRAM]     = "dgram",
35	[SOCK_RAW]       = "raw",
36	[SOCK_SEQPACKET] = "seqpacket",
37	[0] = " ", /* Dummy for avoiding NULL pointer dereference. */
38	[4] = " ", /* Dummy for avoiding NULL pointer dereference. */
39};
40
41/**
42 * tomoyo_parse_ipaddr_union - Parse an IP address.
43 *
44 * @param: Pointer to "struct tomoyo_acl_param".
45 * @ptr:   Pointer to "struct tomoyo_ipaddr_union".
46 *
47 * Returns true on success, false otherwise.
48 */
49bool tomoyo_parse_ipaddr_union(struct tomoyo_acl_param *param,
50			       struct tomoyo_ipaddr_union *ptr)
51{
52	u8 * const min = ptr->ip[0].in6_u.u6_addr8;
53	u8 * const max = ptr->ip[1].in6_u.u6_addr8;
54	char *address = tomoyo_read_token(param);
55	const char *end;
56
57	if (!strchr(address, ':') &&
58	    in4_pton(address, -1, min, '-', &end) > 0) {
59		ptr->is_ipv6 = false;
60		if (!*end)
61			ptr->ip[1].s6_addr32[0] = ptr->ip[0].s6_addr32[0];
62		else if (*end++ != '-' ||
63			 in4_pton(end, -1, max, '\0', &end) <= 0 || *end)
64			return false;
65		return true;
66	}
67	if (in6_pton(address, -1, min, '-', &end) > 0) {
68		ptr->is_ipv6 = true;
69		if (!*end)
70			memmove(max, min, sizeof(u16) * 8);
71		else if (*end++ != '-' ||
72			 in6_pton(end, -1, max, '\0', &end) <= 0 || *end)
73			return false;
74		return true;
75	}
76	return false;
77}
78
79/**
80 * tomoyo_print_ipv4 - Print an IPv4 address.
81 *
82 * @buffer:     Buffer to write to.
83 * @buffer_len: Size of @buffer.
84 * @min_ip:     Pointer to __be32.
85 * @max_ip:     Pointer to __be32.
86 *
87 * Returns nothing.
88 */
89static void tomoyo_print_ipv4(char *buffer, const unsigned int buffer_len,
90			      const __be32 *min_ip, const __be32 *max_ip)
91{
92	snprintf(buffer, buffer_len, "%pI4%c%pI4", min_ip,
93		 *min_ip == *max_ip ? '\0' : '-', max_ip);
94}
95
96/**
97 * tomoyo_print_ipv6 - Print an IPv6 address.
98 *
99 * @buffer:     Buffer to write to.
100 * @buffer_len: Size of @buffer.
101 * @min_ip:     Pointer to "struct in6_addr".
102 * @max_ip:     Pointer to "struct in6_addr".
103 *
104 * Returns nothing.
105 */
106static void tomoyo_print_ipv6(char *buffer, const unsigned int buffer_len,
107			      const struct in6_addr *min_ip,
108			      const struct in6_addr *max_ip)
109{
110	snprintf(buffer, buffer_len, "%pI6c%c%pI6c", min_ip,
111		 !memcmp(min_ip, max_ip, 16) ? '\0' : '-', max_ip);
112}
113
114/**
115 * tomoyo_print_ip - Print an IP address.
116 *
117 * @buf:  Buffer to write to.
118 * @size: Size of @buf.
119 * @ptr:  Pointer to "struct ipaddr_union".
120 *
121 * Returns nothing.
122 */
123void tomoyo_print_ip(char *buf, const unsigned int size,
124		     const struct tomoyo_ipaddr_union *ptr)
125{
126	if (ptr->is_ipv6)
127		tomoyo_print_ipv6(buf, size, &ptr->ip[0], &ptr->ip[1]);
128	else
129		tomoyo_print_ipv4(buf, size, &ptr->ip[0].s6_addr32[0],
130				  &ptr->ip[1].s6_addr32[0]);
131}
132
133/*
134 * Mapping table from "enum tomoyo_network_acl_index" to
135 * "enum tomoyo_mac_index" for inet domain socket.
136 */
137static const u8 tomoyo_inet2mac
138[TOMOYO_SOCK_MAX][TOMOYO_MAX_NETWORK_OPERATION] = {
139	[SOCK_STREAM] = {
140		[TOMOYO_NETWORK_BIND]    = TOMOYO_MAC_NETWORK_INET_STREAM_BIND,
141		[TOMOYO_NETWORK_LISTEN]  =
142		TOMOYO_MAC_NETWORK_INET_STREAM_LISTEN,
143		[TOMOYO_NETWORK_CONNECT] =
144		TOMOYO_MAC_NETWORK_INET_STREAM_CONNECT,
145	},
146	[SOCK_DGRAM] = {
147		[TOMOYO_NETWORK_BIND]    = TOMOYO_MAC_NETWORK_INET_DGRAM_BIND,
148		[TOMOYO_NETWORK_SEND]    = TOMOYO_MAC_NETWORK_INET_DGRAM_SEND,
149	},
150	[SOCK_RAW]    = {
151		[TOMOYO_NETWORK_BIND]    = TOMOYO_MAC_NETWORK_INET_RAW_BIND,
152		[TOMOYO_NETWORK_SEND]    = TOMOYO_MAC_NETWORK_INET_RAW_SEND,
153	},
154};
155
156/*
157 * Mapping table from "enum tomoyo_network_acl_index" to
158 * "enum tomoyo_mac_index" for unix domain socket.
159 */
160static const u8 tomoyo_unix2mac
161[TOMOYO_SOCK_MAX][TOMOYO_MAX_NETWORK_OPERATION] = {
162	[SOCK_STREAM] = {
163		[TOMOYO_NETWORK_BIND]    = TOMOYO_MAC_NETWORK_UNIX_STREAM_BIND,
164		[TOMOYO_NETWORK_LISTEN]  =
165		TOMOYO_MAC_NETWORK_UNIX_STREAM_LISTEN,
166		[TOMOYO_NETWORK_CONNECT] =
167		TOMOYO_MAC_NETWORK_UNIX_STREAM_CONNECT,
168	},
169	[SOCK_DGRAM] = {
170		[TOMOYO_NETWORK_BIND]    = TOMOYO_MAC_NETWORK_UNIX_DGRAM_BIND,
171		[TOMOYO_NETWORK_SEND]    = TOMOYO_MAC_NETWORK_UNIX_DGRAM_SEND,
172	},
173	[SOCK_SEQPACKET] = {
174		[TOMOYO_NETWORK_BIND]    =
175		TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_BIND,
176		[TOMOYO_NETWORK_LISTEN]  =
177		TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_LISTEN,
178		[TOMOYO_NETWORK_CONNECT] =
179		TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_CONNECT,
180	},
181};
182
183/**
184 * tomoyo_same_inet_acl - Check for duplicated "struct tomoyo_inet_acl" entry.
185 *
186 * @a: Pointer to "struct tomoyo_acl_info".
187 * @b: Pointer to "struct tomoyo_acl_info".
188 *
189 * Returns true if @a == @b except permission bits, false otherwise.
190 */
191static bool tomoyo_same_inet_acl(const struct tomoyo_acl_info *a,
192				 const struct tomoyo_acl_info *b)
193{
194	const struct tomoyo_inet_acl *p1 = container_of(a, typeof(*p1), head);
195	const struct tomoyo_inet_acl *p2 = container_of(b, typeof(*p2), head);
196
197	return p1->protocol == p2->protocol &&
198		tomoyo_same_ipaddr_union(&p1->address, &p2->address) &&
199		tomoyo_same_number_union(&p1->port, &p2->port);
200}
201
202/**
203 * tomoyo_same_unix_acl - Check for duplicated "struct tomoyo_unix_acl" entry.
204 *
205 * @a: Pointer to "struct tomoyo_acl_info".
206 * @b: Pointer to "struct tomoyo_acl_info".
207 *
208 * Returns true if @a == @b except permission bits, false otherwise.
209 */
210static bool tomoyo_same_unix_acl(const struct tomoyo_acl_info *a,
211				 const struct tomoyo_acl_info *b)
212{
213	const struct tomoyo_unix_acl *p1 = container_of(a, typeof(*p1), head);
214	const struct tomoyo_unix_acl *p2 = container_of(b, typeof(*p2), head);
215
216	return p1->protocol == p2->protocol &&
217		tomoyo_same_name_union(&p1->name, &p2->name);
218}
219
220/**
221 * tomoyo_merge_inet_acl - Merge duplicated "struct tomoyo_inet_acl" entry.
222 *
223 * @a:         Pointer to "struct tomoyo_acl_info".
224 * @b:         Pointer to "struct tomoyo_acl_info".
225 * @is_delete: True for @a &= ~@b, false for @a |= @b.
226 *
227 * Returns true if @a is empty, false otherwise.
228 */
229static bool tomoyo_merge_inet_acl(struct tomoyo_acl_info *a,
230				  struct tomoyo_acl_info *b,
231				  const bool is_delete)
232{
233	u8 * const a_perm =
234		&container_of(a, struct tomoyo_inet_acl, head)->perm;
235	u8 perm = *a_perm;
236	const u8 b_perm = container_of(b, struct tomoyo_inet_acl, head)->perm;
237
238	if (is_delete)
239		perm &= ~b_perm;
240	else
241		perm |= b_perm;
242	*a_perm = perm;
243	return !perm;
244}
245
246/**
247 * tomoyo_merge_unix_acl - Merge duplicated "struct tomoyo_unix_acl" entry.
248 *
249 * @a:         Pointer to "struct tomoyo_acl_info".
250 * @b:         Pointer to "struct tomoyo_acl_info".
251 * @is_delete: True for @a &= ~@b, false for @a |= @b.
252 *
253 * Returns true if @a is empty, false otherwise.
254 */
255static bool tomoyo_merge_unix_acl(struct tomoyo_acl_info *a,
256				  struct tomoyo_acl_info *b,
257				  const bool is_delete)
258{
259	u8 * const a_perm =
260		&container_of(a, struct tomoyo_unix_acl, head)->perm;
261	u8 perm = *a_perm;
262	const u8 b_perm = container_of(b, struct tomoyo_unix_acl, head)->perm;
263
264	if (is_delete)
265		perm &= ~b_perm;
266	else
267		perm |= b_perm;
268	*a_perm = perm;
269	return !perm;
270}
271
272/**
273 * tomoyo_write_inet_network - Write "struct tomoyo_inet_acl" list.
274 *
275 * @param: Pointer to "struct tomoyo_acl_param".
276 *
277 * Returns 0 on success, negative value otherwise.
278 *
279 * Caller holds tomoyo_read_lock().
280 */
281int tomoyo_write_inet_network(struct tomoyo_acl_param *param)
282{
283	struct tomoyo_inet_acl e = { .head.type = TOMOYO_TYPE_INET_ACL };
284	int error = -EINVAL;
285	u8 type;
286	const char *protocol = tomoyo_read_token(param);
287	const char *operation = tomoyo_read_token(param);
288
289	for (e.protocol = 0; e.protocol < TOMOYO_SOCK_MAX; e.protocol++)
290		if (!strcmp(protocol, tomoyo_proto_keyword[e.protocol]))
291			break;
292	for (type = 0; type < TOMOYO_MAX_NETWORK_OPERATION; type++)
293		if (tomoyo_permstr(operation, tomoyo_socket_keyword[type]))
294			e.perm |= 1 << type;
295	if (e.protocol == TOMOYO_SOCK_MAX || !e.perm)
296		return -EINVAL;
297	if (param->data[0] == '@') {
298		param->data++;
299		e.address.group =
300			tomoyo_get_group(param, TOMOYO_ADDRESS_GROUP);
301		if (!e.address.group)
302			return -ENOMEM;
303	} else {
304		if (!tomoyo_parse_ipaddr_union(param, &e.address))
305			goto out;
306	}
307	if (!tomoyo_parse_number_union(param, &e.port) ||
308	    e.port.values[1] > 65535)
309		goto out;
310	error = tomoyo_update_domain(&e.head, sizeof(e), param,
311				     tomoyo_same_inet_acl,
312				     tomoyo_merge_inet_acl);
313out:
314	tomoyo_put_group(e.address.group);
315	tomoyo_put_number_union(&e.port);
316	return error;
317}
318
319/**
320 * tomoyo_write_unix_network - Write "struct tomoyo_unix_acl" list.
321 *
322 * @param: Pointer to "struct tomoyo_acl_param".
323 *
324 * Returns 0 on success, negative value otherwise.
325 */
326int tomoyo_write_unix_network(struct tomoyo_acl_param *param)
327{
328	struct tomoyo_unix_acl e = { .head.type = TOMOYO_TYPE_UNIX_ACL };
329	int error;
330	u8 type;
331	const char *protocol = tomoyo_read_token(param);
332	const char *operation = tomoyo_read_token(param);
333
334	for (e.protocol = 0; e.protocol < TOMOYO_SOCK_MAX; e.protocol++)
335		if (!strcmp(protocol, tomoyo_proto_keyword[e.protocol]))
336			break;
337	for (type = 0; type < TOMOYO_MAX_NETWORK_OPERATION; type++)
338		if (tomoyo_permstr(operation, tomoyo_socket_keyword[type]))
339			e.perm |= 1 << type;
340	if (e.protocol == TOMOYO_SOCK_MAX || !e.perm)
341		return -EINVAL;
342	if (!tomoyo_parse_name_union(param, &e.name))
343		return -EINVAL;
344	error = tomoyo_update_domain(&e.head, sizeof(e), param,
345				     tomoyo_same_unix_acl,
346				     tomoyo_merge_unix_acl);
347	tomoyo_put_name_union(&e.name);
348	return error;
349}
350
351/**
352 * tomoyo_audit_net_log - Audit network log.
353 *
354 * @r:         Pointer to "struct tomoyo_request_info".
355 * @family:    Name of socket family ("inet" or "unix").
356 * @protocol:  Name of protocol in @family.
357 * @operation: Name of socket operation.
358 * @address:   Name of address.
359 *
360 * Returns 0 on success, negative value otherwise.
361 */
362static int tomoyo_audit_net_log(struct tomoyo_request_info *r,
363				const char *family, const u8 protocol,
364				const u8 operation, const char *address)
365{
366	return tomoyo_supervisor(r, "network %s %s %s %s\n", family,
367				 tomoyo_proto_keyword[protocol],
368				 tomoyo_socket_keyword[operation], address);
369}
370
371/**
372 * tomoyo_audit_inet_log - Audit INET network log.
373 *
374 * @r: Pointer to "struct tomoyo_request_info".
375 *
376 * Returns 0 on success, negative value otherwise.
377 */
378static int tomoyo_audit_inet_log(struct tomoyo_request_info *r)
379{
380	char buf[128];
381	int len;
382	const __be32 *address = r->param.inet_network.address;
383
384	if (r->param.inet_network.is_ipv6)
385		tomoyo_print_ipv6(buf, sizeof(buf), (const struct in6_addr *)
386				  address, (const struct in6_addr *) address);
387	else
388		tomoyo_print_ipv4(buf, sizeof(buf), address, address);
389	len = strlen(buf);
390	snprintf(buf + len, sizeof(buf) - len, " %u",
391		 r->param.inet_network.port);
392	return tomoyo_audit_net_log(r, "inet", r->param.inet_network.protocol,
393				    r->param.inet_network.operation, buf);
394}
395
396/**
397 * tomoyo_audit_unix_log - Audit UNIX network log.
398 *
399 * @r: Pointer to "struct tomoyo_request_info".
400 *
401 * Returns 0 on success, negative value otherwise.
402 */
403static int tomoyo_audit_unix_log(struct tomoyo_request_info *r)
404{
405	return tomoyo_audit_net_log(r, "unix", r->param.unix_network.protocol,
406				    r->param.unix_network.operation,
407				    r->param.unix_network.address->name);
408}
409
410/**
411 * tomoyo_check_inet_acl - Check permission for inet domain socket operation.
412 *
413 * @r:   Pointer to "struct tomoyo_request_info".
414 * @ptr: Pointer to "struct tomoyo_acl_info".
415 *
416 * Returns true if granted, false otherwise.
417 */
418static bool tomoyo_check_inet_acl(struct tomoyo_request_info *r,
419				  const struct tomoyo_acl_info *ptr)
420{
421	const struct tomoyo_inet_acl *acl =
422		container_of(ptr, typeof(*acl), head);
423	const u8 size = r->param.inet_network.is_ipv6 ? 16 : 4;
424
425	if (!(acl->perm & (1 << r->param.inet_network.operation)) ||
426	    !tomoyo_compare_number_union(r->param.inet_network.port,
427					 &acl->port))
428		return false;
429	if (acl->address.group)
430		return tomoyo_address_matches_group
431			(r->param.inet_network.is_ipv6,
432			 r->param.inet_network.address, acl->address.group);
433	return acl->address.is_ipv6 == r->param.inet_network.is_ipv6 &&
434		memcmp(&acl->address.ip[0],
435		       r->param.inet_network.address, size) <= 0 &&
436		memcmp(r->param.inet_network.address,
437		       &acl->address.ip[1], size) <= 0;
438}
439
440/**
441 * tomoyo_check_unix_acl - Check permission for unix domain socket operation.
442 *
443 * @r:   Pointer to "struct tomoyo_request_info".
444 * @ptr: Pointer to "struct tomoyo_acl_info".
445 *
446 * Returns true if granted, false otherwise.
447 */
448static bool tomoyo_check_unix_acl(struct tomoyo_request_info *r,
449				  const struct tomoyo_acl_info *ptr)
450{
451	const struct tomoyo_unix_acl *acl =
452		container_of(ptr, typeof(*acl), head);
453
454	return (acl->perm & (1 << r->param.unix_network.operation)) &&
455		tomoyo_compare_name_union(r->param.unix_network.address,
456					  &acl->name);
457}
458
459/**
460 * tomoyo_inet_entry - Check permission for INET network operation.
461 *
462 * @address: Pointer to "struct tomoyo_addr_info".
463 *
464 * Returns 0 on success, negative value otherwise.
465 */
466static int tomoyo_inet_entry(const struct tomoyo_addr_info *address)
467{
468	const int idx = tomoyo_read_lock();
469	struct tomoyo_request_info r;
470	int error = 0;
471	const u8 type = tomoyo_inet2mac[address->protocol][address->operation];
472
473	if (type && tomoyo_init_request_info(&r, NULL, type)
474	    != TOMOYO_CONFIG_DISABLED) {
475		r.param_type = TOMOYO_TYPE_INET_ACL;
476		r.param.inet_network.protocol = address->protocol;
477		r.param.inet_network.operation = address->operation;
478		r.param.inet_network.is_ipv6 = address->inet.is_ipv6;
479		r.param.inet_network.address = address->inet.address;
480		r.param.inet_network.port = ntohs(address->inet.port);
481		do {
482			tomoyo_check_acl(&r, tomoyo_check_inet_acl);
483			error = tomoyo_audit_inet_log(&r);
484		} while (error == TOMOYO_RETRY_REQUEST);
485	}
486	tomoyo_read_unlock(idx);
487	return error;
488}
489
490/**
491 * tomoyo_check_inet_address - Check permission for inet domain socket's operation.
492 *
493 * @addr:     Pointer to "struct sockaddr".
494 * @addr_len: Size of @addr.
495 * @port:     Port number.
496 * @address:  Pointer to "struct tomoyo_addr_info".
497 *
498 * Returns 0 on success, negative value otherwise.
499 */
500static int tomoyo_check_inet_address(const struct sockaddr *addr,
501				     const unsigned int addr_len,
502				     const u16 port,
503				     struct tomoyo_addr_info *address)
504{
505	struct tomoyo_inet_addr_info *i = &address->inet;
506
507	switch (addr->sa_family) {
508	case AF_INET6:
509		if (addr_len < SIN6_LEN_RFC2133)
510			goto skip;
511		i->is_ipv6 = true;
512		i->address = (__be32 *)
513			((struct sockaddr_in6 *) addr)->sin6_addr.s6_addr;
514		i->port = ((struct sockaddr_in6 *) addr)->sin6_port;
515		break;
516	case AF_INET:
517		if (addr_len < sizeof(struct sockaddr_in))
518			goto skip;
519		i->is_ipv6 = false;
520		i->address = (__be32 *)
521			&((struct sockaddr_in *) addr)->sin_addr;
522		i->port = ((struct sockaddr_in *) addr)->sin_port;
523		break;
524	default:
525		goto skip;
526	}
527	if (address->protocol == SOCK_RAW)
528		i->port = htons(port);
529	return tomoyo_inet_entry(address);
530skip:
531	return 0;
532}
533
534/**
535 * tomoyo_unix_entry - Check permission for UNIX network operation.
536 *
537 * @address: Pointer to "struct tomoyo_addr_info".
538 *
539 * Returns 0 on success, negative value otherwise.
540 */
541static int tomoyo_unix_entry(const struct tomoyo_addr_info *address)
542{
543	const int idx = tomoyo_read_lock();
544	struct tomoyo_request_info r;
545	int error = 0;
546	const u8 type = tomoyo_unix2mac[address->protocol][address->operation];
547
548	if (type && tomoyo_init_request_info(&r, NULL, type)
549	    != TOMOYO_CONFIG_DISABLED) {
550		char *buf = address->unix0.addr;
551		int len = address->unix0.addr_len - sizeof(sa_family_t);
552
553		if (len <= 0) {
554			buf = "anonymous";
555			len = 9;
556		} else if (buf[0]) {
557			len = strnlen(buf, len);
558		}
559		buf = tomoyo_encode2(buf, len);
560		if (buf) {
561			struct tomoyo_path_info addr;
562
563			addr.name = buf;
564			tomoyo_fill_path_info(&addr);
565			r.param_type = TOMOYO_TYPE_UNIX_ACL;
566			r.param.unix_network.protocol = address->protocol;
567			r.param.unix_network.operation = address->operation;
568			r.param.unix_network.address = &addr;
569			do {
570				tomoyo_check_acl(&r, tomoyo_check_unix_acl);
571				error = tomoyo_audit_unix_log(&r);
572			} while (error == TOMOYO_RETRY_REQUEST);
573			kfree(buf);
574		} else
575			error = -ENOMEM;
576	}
577	tomoyo_read_unlock(idx);
578	return error;
579}
580
581/**
582 * tomoyo_check_unix_address - Check permission for unix domain socket's operation.
583 *
584 * @addr:     Pointer to "struct sockaddr".
585 * @addr_len: Size of @addr.
586 * @address:  Pointer to "struct tomoyo_addr_info".
587 *
588 * Returns 0 on success, negative value otherwise.
589 */
590static int tomoyo_check_unix_address(struct sockaddr *addr,
591				     const unsigned int addr_len,
592				     struct tomoyo_addr_info *address)
593{
594	struct tomoyo_unix_addr_info *u = &address->unix0;
595
596	if (addr->sa_family != AF_UNIX)
597		return 0;
598	u->addr = ((struct sockaddr_un *) addr)->sun_path;
599	u->addr_len = addr_len;
600	return tomoyo_unix_entry(address);
601}
602
603/**
604 * tomoyo_kernel_service - Check whether I'm kernel service or not.
605 *
606 * Returns true if I'm kernel service, false otherwise.
607 */
608static bool tomoyo_kernel_service(void)
609{
610	/* Nothing to do if I am a kernel service. */
611	return segment_eq(get_fs(), KERNEL_DS);
612}
613
614/**
615 * tomoyo_sock_family - Get socket's family.
616 *
617 * @sk: Pointer to "struct sock".
618 *
619 * Returns one of PF_INET, PF_INET6, PF_UNIX or 0.
620 */
621static u8 tomoyo_sock_family(struct sock *sk)
622{
623	u8 family;
624
625	if (tomoyo_kernel_service())
626		return 0;
627	family = sk->sk_family;
628	switch (family) {
629	case PF_INET:
630	case PF_INET6:
631	case PF_UNIX:
632		return family;
633	default:
634		return 0;
635	}
636}
637
638/**
639 * tomoyo_socket_listen_permission - Check permission for listening a socket.
640 *
641 * @sock: Pointer to "struct socket".
642 *
643 * Returns 0 on success, negative value otherwise.
644 */
645int tomoyo_socket_listen_permission(struct socket *sock)
646{
647	struct tomoyo_addr_info address;
648	const u8 family = tomoyo_sock_family(sock->sk);
649	const unsigned int type = sock->type;
650	struct sockaddr_storage addr;
651	int addr_len;
652
653	if (!family || (type != SOCK_STREAM && type != SOCK_SEQPACKET))
654		return 0;
655	{
656		const int error = sock->ops->getname(sock, (struct sockaddr *)
657						     &addr, &addr_len, 0);
658
659		if (error)
660			return error;
661	}
662	address.protocol = type;
663	address.operation = TOMOYO_NETWORK_LISTEN;
664	if (family == PF_UNIX)
665		return tomoyo_check_unix_address((struct sockaddr *) &addr,
666						 addr_len, &address);
667	return tomoyo_check_inet_address((struct sockaddr *) &addr, addr_len,
668					 0, &address);
669}
670
671/**
672 * tomoyo_socket_connect_permission - Check permission for setting the remote address of a socket.
673 *
674 * @sock:     Pointer to "struct socket".
675 * @addr:     Pointer to "struct sockaddr".
676 * @addr_len: Size of @addr.
677 *
678 * Returns 0 on success, negative value otherwise.
679 */
680int tomoyo_socket_connect_permission(struct socket *sock,
681				     struct sockaddr *addr, int addr_len)
682{
683	struct tomoyo_addr_info address;
684	const u8 family = tomoyo_sock_family(sock->sk);
685	const unsigned int type = sock->type;
686
687	if (!family)
688		return 0;
689	address.protocol = type;
690	switch (type) {
691	case SOCK_DGRAM:
692	case SOCK_RAW:
693		address.operation = TOMOYO_NETWORK_SEND;
694		break;
695	case SOCK_STREAM:
696	case SOCK_SEQPACKET:
697		address.operation = TOMOYO_NETWORK_CONNECT;
698		break;
699	default:
700		return 0;
701	}
702	if (family == PF_UNIX)
703		return tomoyo_check_unix_address(addr, addr_len, &address);
704	return tomoyo_check_inet_address(addr, addr_len, sock->sk->sk_protocol,
705					 &address);
706}
707
708/**
709 * tomoyo_socket_bind_permission - Check permission for setting the local address of a socket.
710 *
711 * @sock:     Pointer to "struct socket".
712 * @addr:     Pointer to "struct sockaddr".
713 * @addr_len: Size of @addr.
714 *
715 * Returns 0 on success, negative value otherwise.
716 */
717int tomoyo_socket_bind_permission(struct socket *sock, struct sockaddr *addr,
718				  int addr_len)
719{
720	struct tomoyo_addr_info address;
721	const u8 family = tomoyo_sock_family(sock->sk);
722	const unsigned int type = sock->type;
723
724	if (!family)
725		return 0;
726	switch (type) {
727	case SOCK_STREAM:
728	case SOCK_DGRAM:
729	case SOCK_RAW:
730	case SOCK_SEQPACKET:
731		address.protocol = type;
732		address.operation = TOMOYO_NETWORK_BIND;
733		break;
734	default:
735		return 0;
736	}
737	if (family == PF_UNIX)
738		return tomoyo_check_unix_address(addr, addr_len, &address);
739	return tomoyo_check_inet_address(addr, addr_len, sock->sk->sk_protocol,
740					 &address);
741}
742
743/**
744 * tomoyo_socket_sendmsg_permission - Check permission for sending a datagram.
745 *
746 * @sock: Pointer to "struct socket".
747 * @msg:  Pointer to "struct msghdr".
748 * @size: Unused.
749 *
750 * Returns 0 on success, negative value otherwise.
751 */
752int tomoyo_socket_sendmsg_permission(struct socket *sock, struct msghdr *msg,
753				     int size)
754{
755	struct tomoyo_addr_info address;
756	const u8 family = tomoyo_sock_family(sock->sk);
757	const unsigned int type = sock->type;
758
759	if (!msg->msg_name || !family ||
760	    (type != SOCK_DGRAM && type != SOCK_RAW))
761		return 0;
762	address.protocol = type;
763	address.operation = TOMOYO_NETWORK_SEND;
764	if (family == PF_UNIX)
765		return tomoyo_check_unix_address((struct sockaddr *)
766						 msg->msg_name,
767						 msg->msg_namelen, &address);
768	return tomoyo_check_inet_address((struct sockaddr *) msg->msg_name,
769					 msg->msg_namelen,
770					 sock->sk->sk_protocol, &address);
771}
772