1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2013 Tom Gundersen <teg@jklm.no>
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 #include <netinet/in.h>
23 #include <netinet/ether.h>
26 #include <linux/netlink.h>
27 #include <linux/veth.h>
30 #include <linux/if_tunnel.h>
31 #include <linux/if_bridge.h>
38 #include "rtnl-util.h"
39 #include "rtnl-internal.h"
40 #include "rtnl-types.h"
42 #define GET_CONTAINER(m, i) ((i) < (m)->n_containers ? (struct rtattr*)((uint8_t*)(m)->hdr + (m)->container_offsets[i]) : NULL)
43 #define PUSH_CONTAINER(m, new) (m)->container_offsets[(m)->n_containers ++] = (uint8_t*)(new) - (uint8_t*)(m)->hdr;
45 static int message_new_empty(sd_rtnl *rtnl, sd_rtnl_message **ret) {
48 assert_return(ret, -EINVAL);
50 /* Note that 'rtnl' is curretly unused, if we start using it internally
51 we must take care to avoid problems due to mutual references between
52 busses and their queued messages. See sd-bus.
55 m = new0(sd_rtnl_message, 1);
59 m->n_ref = REFCNT_INIT;
68 int message_new(sd_rtnl *rtnl, sd_rtnl_message **ret, uint16_t type) {
69 _cleanup_rtnl_message_unref_ sd_rtnl_message *m = NULL;
70 const NLType *nl_type;
74 r = type_system_get_type(NULL, &nl_type, type);
78 assert(nl_type->type == NLA_NESTED);
80 r = message_new_empty(rtnl, &m);
84 size = NLMSG_SPACE(nl_type->size);
86 assert(size >= sizeof(struct nlmsghdr));
87 m->hdr = malloc0(size);
91 m->hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
93 m->container_type_system[0] = nl_type->type_system;
94 m->hdr->nlmsg_len = size;
95 m->hdr->nlmsg_type = type;
103 int sd_rtnl_message_route_set_dst_prefixlen(sd_rtnl_message *m, unsigned char prefixlen) {
106 assert_return(m, -EINVAL);
107 assert_return(m->hdr, -EINVAL);
108 assert_return(rtnl_message_type_is_route(m->hdr->nlmsg_type), -EINVAL);
110 rtm = NLMSG_DATA(m->hdr);
112 if ((rtm->rtm_family == AF_INET && prefixlen > 32) ||
113 (rtm->rtm_family == AF_INET6 && prefixlen > 128))
116 rtm->rtm_dst_len = prefixlen;
121 int sd_rtnl_message_route_set_scope(sd_rtnl_message *m, unsigned char scope) {
124 assert_return(m, -EINVAL);
125 assert_return(m->hdr, -EINVAL);
126 assert_return(rtnl_message_type_is_route(m->hdr->nlmsg_type), -EINVAL);
128 rtm = NLMSG_DATA(m->hdr);
130 rtm->rtm_scope = scope;
135 int sd_rtnl_message_new_route(sd_rtnl *rtnl, sd_rtnl_message **ret,
136 uint16_t nlmsg_type, unsigned char rtm_family) {
140 assert_return(rtnl_message_type_is_route(nlmsg_type), -EINVAL);
141 assert_return(rtm_family == AF_INET || rtm_family == AF_INET6, -EINVAL);
142 assert_return(ret, -EINVAL);
144 r = message_new(rtnl, ret, nlmsg_type);
148 if (nlmsg_type == RTM_NEWROUTE)
149 (*ret)->hdr->nlmsg_flags |= NLM_F_CREATE | NLM_F_APPEND;
151 rtm = NLMSG_DATA((*ret)->hdr);
153 rtm->rtm_family = rtm_family;
154 rtm->rtm_scope = RT_SCOPE_UNIVERSE;
155 rtm->rtm_type = RTN_UNICAST;
156 rtm->rtm_table = RT_TABLE_MAIN;
157 rtm->rtm_protocol = RTPROT_BOOT;
162 int sd_rtnl_message_link_set_flags(sd_rtnl_message *m, unsigned flags, unsigned change) {
163 struct ifinfomsg *ifi;
165 assert_return(m, -EINVAL);
166 assert_return(m->hdr, -EINVAL);
167 assert_return(rtnl_message_type_is_link(m->hdr->nlmsg_type), -EINVAL);
168 assert_return(change, -EINVAL);
170 ifi = NLMSG_DATA(m->hdr);
172 ifi->ifi_flags = flags;
173 ifi->ifi_change = change;
178 int sd_rtnl_message_link_set_type(sd_rtnl_message *m, unsigned type) {
179 struct ifinfomsg *ifi;
181 assert_return(m, -EINVAL);
182 assert_return(m->hdr, -EINVAL);
183 assert_return(rtnl_message_type_is_link(m->hdr->nlmsg_type), -EINVAL);
185 ifi = NLMSG_DATA(m->hdr);
187 ifi->ifi_type = type;
192 int sd_rtnl_message_new_link(sd_rtnl *rtnl, sd_rtnl_message **ret,
193 uint16_t nlmsg_type, int index) {
194 struct ifinfomsg *ifi;
197 assert_return(rtnl_message_type_is_link(nlmsg_type), -EINVAL);
198 assert_return(nlmsg_type != RTM_DELLINK || index > 0, -EINVAL);
199 assert_return(ret, -EINVAL);
201 r = message_new(rtnl, ret, nlmsg_type);
205 if (nlmsg_type == RTM_NEWLINK)
206 (*ret)->hdr->nlmsg_flags |= NLM_F_CREATE | NLM_F_EXCL;
208 ifi = NLMSG_DATA((*ret)->hdr);
210 ifi->ifi_family = AF_UNSPEC;
211 ifi->ifi_index = index;
216 int sd_rtnl_message_request_dump(sd_rtnl_message *m, int dump) {
217 assert_return(m, -EINVAL);
218 assert_return(m->hdr, -EINVAL);
219 assert_return(m->hdr->nlmsg_type == RTM_GETLINK ||
220 m->hdr->nlmsg_type == RTM_GETADDR ||
221 m->hdr->nlmsg_type == RTM_GETROUTE,
225 m->hdr->nlmsg_flags |= NLM_F_DUMP;
227 m->hdr->nlmsg_flags &= ~NLM_F_DUMP;
232 int sd_rtnl_message_addr_set_prefixlen(sd_rtnl_message *m, unsigned char prefixlen) {
233 struct ifaddrmsg *ifa;
235 assert_return(m, -EINVAL);
236 assert_return(m->hdr, -EINVAL);
237 assert_return(rtnl_message_type_is_addr(m->hdr->nlmsg_type), -EINVAL);
239 ifa = NLMSG_DATA(m->hdr);
241 if ((ifa->ifa_family == AF_INET && prefixlen > 32) ||
242 (ifa->ifa_family == AF_INET6 && prefixlen > 128))
245 ifa->ifa_prefixlen = prefixlen;
250 int sd_rtnl_message_addr_set_flags(sd_rtnl_message *m, unsigned char flags) {
251 struct ifaddrmsg *ifa;
253 assert_return(m, -EINVAL);
254 assert_return(m->hdr, -EINVAL);
255 assert_return(rtnl_message_type_is_addr(m->hdr->nlmsg_type), -EINVAL);
257 ifa = NLMSG_DATA(m->hdr);
259 ifa->ifa_flags = flags;
264 int sd_rtnl_message_addr_set_scope(sd_rtnl_message *m, unsigned char scope) {
265 struct ifaddrmsg *ifa;
267 assert_return(m, -EINVAL);
268 assert_return(m->hdr, -EINVAL);
269 assert_return(rtnl_message_type_is_addr(m->hdr->nlmsg_type), -EINVAL);
271 ifa = NLMSG_DATA(m->hdr);
273 ifa->ifa_scope = scope;
278 int sd_rtnl_message_addr_get_family(sd_rtnl_message *m, unsigned char *family) {
279 struct ifaddrmsg *ifa;
281 assert_return(m, -EINVAL);
282 assert_return(m->hdr, -EINVAL);
283 assert_return(rtnl_message_type_is_addr(m->hdr->nlmsg_type), -EINVAL);
284 assert_return(family, -EINVAL);
286 ifa = NLMSG_DATA(m->hdr);
288 *family = ifa->ifa_family;
293 int sd_rtnl_message_addr_get_scope(sd_rtnl_message *m, unsigned char *scope) {
294 struct ifaddrmsg *ifa;
296 assert_return(m, -EINVAL);
297 assert_return(m->hdr, -EINVAL);
298 assert_return(rtnl_message_type_is_addr(m->hdr->nlmsg_type), -EINVAL);
299 assert_return(scope, -EINVAL);
301 ifa = NLMSG_DATA(m->hdr);
303 *scope = ifa->ifa_scope;
308 int sd_rtnl_message_addr_get_flags(sd_rtnl_message *m, unsigned char *flags) {
309 struct ifaddrmsg *ifa;
311 assert_return(m, -EINVAL);
312 assert_return(m->hdr, -EINVAL);
313 assert_return(rtnl_message_type_is_addr(m->hdr->nlmsg_type), -EINVAL);
314 assert_return(flags, -EINVAL);
316 ifa = NLMSG_DATA(m->hdr);
318 *flags = ifa->ifa_flags;
323 int sd_rtnl_message_addr_get_ifindex(sd_rtnl_message *m, int *ifindex) {
324 struct ifaddrmsg *ifa;
326 assert_return(m, -EINVAL);
327 assert_return(m->hdr, -EINVAL);
328 assert_return(rtnl_message_type_is_addr(m->hdr->nlmsg_type), -EINVAL);
329 assert_return(ifindex, -EINVAL);
331 ifa = NLMSG_DATA(m->hdr);
333 *ifindex = ifa->ifa_index;
338 int sd_rtnl_message_new_addr(sd_rtnl *rtnl, sd_rtnl_message **ret,
339 uint16_t nlmsg_type, int index,
340 unsigned char family) {
341 struct ifaddrmsg *ifa;
344 assert_return(rtnl_message_type_is_addr(nlmsg_type), -EINVAL);
345 assert_return((nlmsg_type == RTM_GETADDR && index == 0) ||
347 assert_return((nlmsg_type == RTM_GETADDR && family == AF_UNSPEC) ||
348 family == AF_INET || family == AF_INET6, -EINVAL);
349 assert_return(ret, -EINVAL);
351 r = message_new(rtnl, ret, nlmsg_type);
355 if (nlmsg_type == RTM_GETADDR)
356 (*ret)->hdr->nlmsg_flags |= NLM_F_DUMP;
358 ifa = NLMSG_DATA((*ret)->hdr);
360 ifa->ifa_index = index;
361 ifa->ifa_family = family;
362 if (family == AF_INET)
363 ifa->ifa_prefixlen = 32;
364 else if (family == AF_INET6)
365 ifa->ifa_prefixlen = 128;
370 int sd_rtnl_message_new_addr_update(sd_rtnl *rtnl, sd_rtnl_message **ret,
371 int index, unsigned char family) {
374 r = sd_rtnl_message_new_addr(rtnl, ret, RTM_NEWADDR, index, family);
378 (*ret)->hdr->nlmsg_flags |= NLM_F_REPLACE;
383 sd_rtnl_message *sd_rtnl_message_ref(sd_rtnl_message *m) {
385 assert_se(REFCNT_INC(m->n_ref) >= 2);
390 sd_rtnl_message *sd_rtnl_message_unref(sd_rtnl_message *m) {
391 if (m && REFCNT_DEC(m->n_ref) <= 0) {
396 for (i = 0; i <= m->n_containers; i++)
397 free(m->rta_offset_tb[i]);
399 sd_rtnl_message_unref(m->next);
407 int sd_rtnl_message_get_type(sd_rtnl_message *m, uint16_t *type) {
408 assert_return(m, -EINVAL);
409 assert_return(type, -EINVAL);
411 *type = m->hdr->nlmsg_type;
416 int sd_rtnl_message_is_broadcast(sd_rtnl_message *m) {
417 assert_return(m, -EINVAL);
419 return !m->hdr->nlmsg_pid;
422 int sd_rtnl_message_link_get_ifindex(sd_rtnl_message *m, int *ifindex) {
423 struct ifinfomsg *ifi;
425 assert_return(m, -EINVAL);
426 assert_return(m->hdr, -EINVAL);
427 assert_return(rtnl_message_type_is_link(m->hdr->nlmsg_type), -EINVAL);
428 assert_return(ifindex, -EINVAL);
430 ifi = NLMSG_DATA(m->hdr);
432 *ifindex = ifi->ifi_index;
437 int sd_rtnl_message_link_get_flags(sd_rtnl_message *m, unsigned *flags) {
438 struct ifinfomsg *ifi;
440 assert_return(m, -EINVAL);
441 assert_return(m->hdr, -EINVAL);
442 assert_return(rtnl_message_type_is_link(m->hdr->nlmsg_type), -EINVAL);
443 assert_return(flags, -EINVAL);
445 ifi = NLMSG_DATA(m->hdr);
447 *flags = ifi->ifi_flags;
452 /* If successful the updated message will be correctly aligned, if
453 unsuccessful the old message is untouched. */
454 static int add_rtattr(sd_rtnl_message *m, unsigned short type, const void *data, size_t data_length) {
455 uint32_t rta_length, message_length;
456 struct nlmsghdr *new_hdr;
464 assert(NLMSG_ALIGN(m->hdr->nlmsg_len) == m->hdr->nlmsg_len);
465 assert(!data || data_length > 0);
466 assert(data || m->n_containers < RTNL_CONTAINER_DEPTH);
468 /* get the size of the new rta attribute (with padding at the end) */
469 rta_length = RTA_LENGTH(data_length);
471 /* get the new message size (with padding at the end) */
472 message_length = m->hdr->nlmsg_len + RTA_ALIGN(rta_length);
474 /* realloc to fit the new attribute */
475 new_hdr = realloc(m->hdr, message_length);
480 /* get pointer to the attribute we are about to add */
481 rta = (struct rtattr *) ((uint8_t *) m->hdr + m->hdr->nlmsg_len);
483 /* if we are inside containers, extend them */
484 for (i = 0; i < m->n_containers; i++)
485 GET_CONTAINER(m, i)->rta_len += message_length - m->hdr->nlmsg_len;
487 /* fill in the attribute */
488 rta->rta_type = type;
489 rta->rta_len = rta_length;
491 //TODO: simply return this value rather than check for !data
492 /* this is the start of a new container */
493 m->container_offsets[m->n_containers ++] = m->hdr->nlmsg_len;
495 /* we don't deal with the case where the user lies about the type
496 * and gives us too little data (so don't do that)
498 padding = mempcpy(RTA_DATA(rta), data, data_length);
499 /* make sure also the padding at the end of the message is initialized */
501 (uint8_t *) m->hdr + message_length - (uint8_t *) padding);
504 /* update message size */
505 m->hdr->nlmsg_len = message_length;
510 static int message_attribute_has_type(sd_rtnl_message *m, uint16_t attribute_type, uint16_t data_type) {
514 r = type_system_get_type(m->container_type_system[m->n_containers], &type, attribute_type);
518 if (type->type != data_type)
524 int sd_rtnl_message_append_string(sd_rtnl_message *m, unsigned short type, const char *data) {
528 assert_return(m, -EINVAL);
529 assert_return(!m->sealed, -EPERM);
530 assert_return(data, -EINVAL);
532 r = message_attribute_has_type(m, type, NLA_STRING);
539 length = strnlen(data, size);
543 length = strlen(data);
545 r = add_rtattr(m, type, data, length + 1);
552 int sd_rtnl_message_append_u8(sd_rtnl_message *m, unsigned short type, uint8_t data) {
555 assert_return(m, -EINVAL);
556 assert_return(!m->sealed, -EPERM);
558 r = message_attribute_has_type(m, type, NLA_U8);
562 r = add_rtattr(m, type, &data, sizeof(uint8_t));
570 int sd_rtnl_message_append_u16(sd_rtnl_message *m, unsigned short type, uint16_t data) {
573 assert_return(m, -EINVAL);
574 assert_return(!m->sealed, -EPERM);
576 r = message_attribute_has_type(m, type, NLA_U16);
580 r = add_rtattr(m, type, &data, sizeof(uint16_t));
587 int sd_rtnl_message_append_u32(sd_rtnl_message *m, unsigned short type, uint32_t data) {
590 assert_return(m, -EINVAL);
591 assert_return(!m->sealed, -EPERM);
593 r = message_attribute_has_type(m, type, NLA_U32);
597 r = add_rtattr(m, type, &data, sizeof(uint32_t));
604 int sd_rtnl_message_append_in_addr(sd_rtnl_message *m, unsigned short type, const struct in_addr *data) {
607 assert_return(m, -EINVAL);
608 assert_return(!m->sealed, -EPERM);
609 assert_return(data, -EINVAL);
611 r = message_attribute_has_type(m, type, NLA_IN_ADDR);
615 r = add_rtattr(m, type, data, sizeof(struct in_addr));
622 int sd_rtnl_message_append_in6_addr(sd_rtnl_message *m, unsigned short type, const struct in6_addr *data) {
625 assert_return(m, -EINVAL);
626 assert_return(!m->sealed, -EPERM);
627 assert_return(data, -EINVAL);
629 r = message_attribute_has_type(m, type, NLA_IN_ADDR);
633 r = add_rtattr(m, type, data, sizeof(struct in6_addr));
640 int sd_rtnl_message_append_ether_addr(sd_rtnl_message *m, unsigned short type, const struct ether_addr *data) {
643 assert_return(m, -EINVAL);
644 assert_return(!m->sealed, -EPERM);
645 assert_return(data, -EINVAL);
647 r = message_attribute_has_type(m, type, NLA_ETHER_ADDR);
651 r = add_rtattr(m, type, data, ETH_ALEN);
658 int sd_rtnl_message_append_cache_info(sd_rtnl_message *m, unsigned short type, const struct ifa_cacheinfo *info) {
661 assert_return(m, -EINVAL);
662 assert_return(!m->sealed, -EPERM);
663 assert_return(info, -EINVAL);
665 r = message_attribute_has_type(m, type, NLA_CACHE_INFO);
669 r = add_rtattr(m, type, info, sizeof(struct ifa_cacheinfo));
676 int sd_rtnl_message_open_container(sd_rtnl_message *m, unsigned short type) {
680 assert_return(m, -EINVAL);
681 assert_return(!m->sealed, -EPERM);
683 r = message_attribute_has_type(m, type, NLA_NESTED);
689 r = type_system_get_type_system(m->container_type_system[m->n_containers],
690 &m->container_type_system[m->n_containers + 1],
695 r = add_rtattr(m, type, NULL, size);
702 int sd_rtnl_message_open_container_union(sd_rtnl_message *m, unsigned short type, const char *key) {
703 const NLTypeSystemUnion *type_system_union;
706 assert_return(m, -EINVAL);
707 assert_return(!m->sealed, -EPERM);
709 r = type_system_get_type_system_union(m->container_type_system[m->n_containers], &type_system_union, type);
713 r = type_system_union_get_type_system(type_system_union,
714 &m->container_type_system[m->n_containers + 1],
719 r = sd_rtnl_message_append_string(m, type_system_union->match, key);
723 /* do we evere need non-null size */
724 r = add_rtattr(m, type, NULL, 0);
732 int sd_rtnl_message_close_container(sd_rtnl_message *m) {
733 assert_return(m, -EINVAL);
734 assert_return(!m->sealed, -EPERM);
735 assert_return(m->n_containers > 0, -EINVAL);
737 m->container_type_system[m->n_containers] = NULL;
743 int rtnl_message_read_internal(sd_rtnl_message *m, unsigned short type, void **data) {
746 assert_return(m, -EINVAL);
747 assert_return(m->sealed, -EPERM);
748 assert_return(data, -EINVAL);
749 assert(m->n_containers <= RTNL_CONTAINER_DEPTH);
750 assert(m->rta_offset_tb[m->n_containers]);
751 assert(type < m->rta_tb_size[m->n_containers]);
753 if(!m->rta_offset_tb[m->n_containers][type])
756 rta = (struct rtattr*)((uint8_t *) m->hdr + m->rta_offset_tb[m->n_containers][type]);
758 *data = RTA_DATA(rta);
760 return RTA_PAYLOAD(rta);
763 int sd_rtnl_message_read_string(sd_rtnl_message *m, unsigned short type, char **data) {
767 r = message_attribute_has_type(m, type, NLA_STRING);
771 r = rtnl_message_read_internal(m, type, &attr_data);
774 else if (strnlen(attr_data, r) >= (size_t) r)
777 *data = (char *) attr_data;
782 int sd_rtnl_message_read_u8(sd_rtnl_message *m, unsigned short type, uint8_t *data) {
786 r = message_attribute_has_type(m, type, NLA_U8);
790 r = rtnl_message_read_internal(m, type, &attr_data);
793 else if ((size_t) r < sizeof(uint8_t))
796 *data = *(uint8_t *) attr_data;
801 int sd_rtnl_message_read_u16(sd_rtnl_message *m, unsigned short type, uint16_t *data) {
805 r = message_attribute_has_type(m, type, NLA_U16);
809 r = rtnl_message_read_internal(m, type, &attr_data);
812 else if ((size_t) r < sizeof(uint16_t))
815 *data = *(uint16_t *) attr_data;
820 int sd_rtnl_message_read_u32(sd_rtnl_message *m, unsigned short type, uint32_t *data) {
824 r = message_attribute_has_type(m, type, NLA_U32);
828 r = rtnl_message_read_internal(m, type, &attr_data);
831 else if ((size_t)r < sizeof(uint32_t))
834 *data = *(uint32_t *) attr_data;
839 int sd_rtnl_message_read_ether_addr(sd_rtnl_message *m, unsigned short type, struct ether_addr *data) {
843 r = message_attribute_has_type(m, type, NLA_ETHER_ADDR);
847 r = rtnl_message_read_internal(m, type, &attr_data);
850 else if ((size_t)r < sizeof(struct ether_addr))
853 memcpy(data, attr_data, sizeof(struct ether_addr));
858 int sd_rtnl_message_read_cache_info(sd_rtnl_message *m, unsigned short type, struct ifa_cacheinfo *info) {
862 r = message_attribute_has_type(m, type, NLA_CACHE_INFO);
866 r = rtnl_message_read_internal(m, type, &attr_data);
869 else if ((size_t)r < sizeof(struct ifa_cacheinfo))
872 memcpy(info, attr_data, sizeof(struct ifa_cacheinfo));
877 int sd_rtnl_message_read_in_addr(sd_rtnl_message *m, unsigned short type, struct in_addr *data) {
881 r = message_attribute_has_type(m, type, NLA_IN_ADDR);
885 r = rtnl_message_read_internal(m, type, &attr_data);
888 else if ((size_t)r < sizeof(struct in_addr))
891 memcpy(data, attr_data, sizeof(struct in_addr));
896 int sd_rtnl_message_read_in6_addr(sd_rtnl_message *m, unsigned short type, struct in6_addr *data) {
900 r = message_attribute_has_type(m, type, NLA_IN_ADDR);
904 r = rtnl_message_read_internal(m, type, &attr_data);
907 else if ((size_t)r < sizeof(struct in6_addr))
910 memcpy(data, attr_data, sizeof(struct in6_addr));
915 int sd_rtnl_message_enter_container(sd_rtnl_message *m, unsigned short type) {
916 const NLType *nl_type;
917 const NLTypeSystem *type_system;
922 assert_return(m, -EINVAL);
923 assert_return(m->n_containers < RTNL_CONTAINER_DEPTH, -EINVAL);
925 r = type_system_get_type(m->container_type_system[m->n_containers],
931 if (nl_type->type == NLA_NESTED) {
932 r = type_system_get_type_system(m->container_type_system[m->n_containers],
937 } else if (nl_type->type == NLA_UNION) {
938 const NLTypeSystemUnion *type_system_union;
941 r = type_system_get_type_system_union(m->container_type_system[m->n_containers],
947 r = sd_rtnl_message_read_string(m, type_system_union->match, &key);
951 r = type_system_union_get_type_system(type_system_union,
959 r = rtnl_message_read_internal(m, type, &container);
967 r = rtnl_message_parse(m,
968 &m->rta_offset_tb[m->n_containers],
969 &m->rta_tb_size[m->n_containers],
978 m->container_type_system[m->n_containers] = type_system;
983 int sd_rtnl_message_exit_container(sd_rtnl_message *m) {
984 assert_return(m, -EINVAL);
985 assert_return(m->sealed, -EINVAL);
986 assert_return(m->n_containers > 0, -EINVAL);
988 free(m->rta_offset_tb[m->n_containers]);
989 m->rta_offset_tb[m->n_containers] = NULL;
990 m->container_type_system[m->n_containers] = NULL;
997 uint32_t rtnl_message_get_serial(sd_rtnl_message *m) {
1001 return m->hdr->nlmsg_seq;
1004 int sd_rtnl_message_get_errno(sd_rtnl_message *m) {
1005 struct nlmsgerr *err;
1007 assert_return(m, -EINVAL);
1008 assert_return(m->hdr, -EINVAL);
1010 if (m->hdr->nlmsg_type != NLMSG_ERROR)
1013 err = NLMSG_DATA(m->hdr);
1018 int rtnl_message_parse(sd_rtnl_message *m,
1019 size_t **rta_offset_tb,
1020 unsigned short *rta_tb_size,
1023 unsigned int rt_len) {
1024 unsigned short type;
1027 tb = new0(size_t, max + 1);
1031 *rta_tb_size = max + 1;
1033 for (; RTA_OK(rta, rt_len); rta = RTA_NEXT(rta, rt_len)) {
1034 type = rta->rta_type;
1036 /* if the kernel is newer than the headers we used
1037 when building, we ignore out-of-range attributes
1043 log_debug("rtnl: message parse - overwriting repeated attribute");
1045 tb[type] = (uint8_t *) rta - (uint8_t *) m->hdr;
1048 *rta_offset_tb = tb;
1053 /* returns the number of bytes sent, or a negative error code */
1054 int socket_write_message(sd_rtnl *nl, sd_rtnl_message *m) {
1057 struct sockaddr_nl nl;
1059 .nl.nl_family = AF_NETLINK,
1067 k = sendto(nl->fd, m->hdr, m->hdr->nlmsg_len,
1068 0, &addr.sa, sizeof(addr));
1070 return (errno == EAGAIN) ? 0 : -errno;
1075 /* On success, the number of bytes received is returned and *ret points to the received message
1076 * which has a valid header and the correct size.
1077 * If nothing useful was received 0 is returned.
1078 * On failure, a negative error code is returned.
1080 int socket_read_message(sd_rtnl *rtnl) {
1081 _cleanup_rtnl_message_unref_ sd_rtnl_message *first = NULL;
1082 uint8_t cred_buffer[CMSG_SPACE(sizeof(struct ucred))];
1083 struct iovec iov = {};
1084 struct msghdr msg = {
1087 .msg_control = cred_buffer,
1088 .msg_controllen = sizeof(cred_buffer),
1090 struct cmsghdr *cmsg;
1091 bool auth = false, multi_part = false, done = false;
1092 struct nlmsghdr *new_msg;
1098 assert(rtnl->rbuffer);
1099 assert(rtnl->rbuffer_allocated >= sizeof(struct nlmsghdr));
1101 /* read nothing, just get the pending message size */
1102 r = recvmsg(rtnl->fd, &msg, MSG_PEEK | MSG_TRUNC);
1105 return (errno == EAGAIN) ? 0 : -errno;
1107 /* connection was closed by the kernel */
1112 /* make room for the pending message */
1113 if (!greedy_realloc((void **)&rtnl->rbuffer,
1114 &rtnl->rbuffer_allocated,
1115 len, sizeof(uint8_t)))
1118 iov.iov_base = rtnl->rbuffer;
1119 iov.iov_len = rtnl->rbuffer_allocated;
1121 r = recvmsg(rtnl->fd, &msg, MSG_TRUNC);
1124 return (errno == EAGAIN) ? 0 : -errno;
1126 /* connection was closed by the kernel */
1131 if (len > rtnl->rbuffer_allocated)
1132 /* message did not fit in read buffer */
1135 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
1136 if (cmsg->cmsg_level == SOL_SOCKET &&
1137 cmsg->cmsg_type == SCM_CREDENTIALS &&
1138 cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred))) {
1139 struct ucred *ucred = (void *)CMSG_DATA(cmsg);
1141 /* from the kernel */
1142 if (ucred->uid == 0 && ucred->pid == 0) {
1150 /* not from the kernel, ignore */
1153 if (NLMSG_OK(rtnl->rbuffer, len) && rtnl->rbuffer->nlmsg_flags & NLM_F_MULTI) {
1156 for (i = 0; i < rtnl->rqueue_partial_size; i++) {
1157 if (rtnl_message_get_serial(rtnl->rqueue_partial[i]) ==
1158 rtnl->rbuffer->nlmsg_seq) {
1159 first = rtnl->rqueue_partial[i];
1165 for (new_msg = rtnl->rbuffer; NLMSG_OK(new_msg, len); new_msg = NLMSG_NEXT(new_msg, len)) {
1166 _cleanup_rtnl_message_unref_ sd_rtnl_message *m = NULL;
1167 const NLType *nl_type;
1169 if (new_msg->nlmsg_pid && new_msg->nlmsg_pid != rtnl->sockaddr.nl.nl_pid)
1170 /* not broadcast and not for us */
1173 if (new_msg->nlmsg_type == NLMSG_NOOP)
1174 /* silently drop noop messages */
1177 if (new_msg->nlmsg_type == NLMSG_DONE) {
1178 /* finished reading multi-part message */
1183 /* check that we support this message type */
1184 r = type_system_get_type(NULL, &nl_type, new_msg->nlmsg_type);
1187 log_debug("sd-rtnl: ignored message with unknown type: %u",
1188 new_msg->nlmsg_type);
1193 /* check that the size matches the message type */
1194 if (new_msg->nlmsg_len < NLMSG_LENGTH(nl_type->size))
1197 r = message_new_empty(rtnl, &m);
1201 m->hdr = memdup(new_msg, new_msg->nlmsg_len);
1205 /* seal and parse the top-level message */
1206 r = sd_rtnl_message_rewind(m);
1210 /* push the message onto the multi-part message stack */
1218 log_debug("sd-rtnl: discarding %zu bytes of incoming message", len);
1223 if (!multi_part || done) {
1224 /* we got a complete message, push it on the read queue */
1225 r = rtnl_rqueue_make_room(rtnl);
1229 rtnl->rqueue[rtnl->rqueue_size ++] = first;
1232 if (multi_part && (i < rtnl->rqueue_partial_size)) {
1233 /* remove the message form the partial read queue */
1234 memmove(rtnl->rqueue_partial + i,rtnl->rqueue_partial + i + 1,
1235 sizeof(sd_rtnl_message*) * (rtnl->rqueue_partial_size - i - 1));
1236 rtnl->rqueue_partial_size --;
1241 /* we only got a partial multi-part message, push it on the
1242 partial read queue */
1243 if (i < rtnl->rqueue_partial_size) {
1244 rtnl->rqueue_partial[i] = first;
1246 r = rtnl_rqueue_partial_make_room(rtnl);
1250 rtnl->rqueue_partial[rtnl->rqueue_partial_size ++] = first;
1258 int sd_rtnl_message_rewind(sd_rtnl_message *m) {
1263 assert_return(m, -EINVAL);
1265 /* don't allow appending to message once parsed */
1267 rtnl_message_seal(m);
1269 for (i = 1; i <= m->n_containers; i++) {
1270 free(m->rta_offset_tb[i]);
1271 m->rta_offset_tb[i] = NULL;
1272 m->rta_tb_size[i] = 0;
1273 m->container_type_system[i] = NULL;
1276 m->n_containers = 0;
1278 if (m->rta_offset_tb[0]) {
1279 /* top-level attributes have already been parsed */
1285 r = type_system_get_type(NULL, &type, m->hdr->nlmsg_type);
1289 if (type->type == NLA_NESTED) {
1290 const NLTypeSystem *type_system = type->type_system;
1292 assert(type_system);
1294 m->container_type_system[0] = type_system;
1296 r = rtnl_message_parse(m,
1297 &m->rta_offset_tb[m->n_containers],
1298 &m->rta_tb_size[m->n_containers],
1300 (struct rtattr*)((uint8_t*)NLMSG_DATA(m->hdr) +
1301 NLMSG_ALIGN(type->size)),
1302 NLMSG_PAYLOAD(m->hdr, type->size));
1310 void rtnl_message_seal(sd_rtnl_message *m) {
1317 sd_rtnl_message *sd_rtnl_message_next(sd_rtnl_message *m) {
1318 assert_return(m, NULL);