netlink-message.c revision 0610939d6bd21873cd2a8d945daff86c477a5015
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer/***
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer This file is part of systemd.
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
fff87a35d9e26c0d4ea41273a963c0eb20e18da4Zbigniew Jędrzejewski-Szmek Copyright 2013 Tom Gundersen <teg@jklm.no>
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier systemd is free software; you can redistribute it and/or modify it
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer under the terms of the GNU Lesser General Public License as published by
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer the Free Software Foundation; either version 2.1 of the License, or
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer (at your option) any later version.
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier systemd is distributed in the hope that it will be useful, but
278d5115470919319c514ea37d7b14e3f7d0580bEvgeny Vereshchagin WITHOUT ANY WARRANTY; without even the implied warranty of
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier Lesser General Public License for more details.
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
32d965851d8cbb39f8ee0eeaf76a89e8f5fc174fLennart Poettering You should have received a copy of the GNU Lesser General Public License
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer along with systemd; If not, see <http://www.gnu.org/licenses/>.
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer***/
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
d9890f4ed47c0d565915360d8bae3b7a1428f285Harald Hoyer#include <netinet/in.h>
c6a77179a4097df355f0f04b8f3260c76b5e515cRonny Chevalier#include <stdbool.h>
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier#include <unistd.h>
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer
c6a77179a4097df355f0f04b8f3260c76b5e515cRonny Chevalier#include "util.h"
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer#include "socket-util.h"
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer#include "formats-util.h"
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier#include "refcnt.h"
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier#include "missing.h"
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer#include "sd-netlink.h"
7b17d413b11bfbdb4442c87b1db25b37ed5162acHarald Hoyer#include "netlink-util.h"
d9890f4ed47c0d565915360d8bae3b7a1428f285Harald Hoyer#include "netlink-internal.h"
d9890f4ed47c0d565915360d8bae3b7a1428f285Harald Hoyer#include "netlink-types.h"
d9890f4ed47c0d565915360d8bae3b7a1428f285Harald Hoyer
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer#define GET_CONTAINER(m, i) ((i) < (m)->n_containers ? (struct rtattr*)((uint8_t*)(m)->hdr + (m)->containers[i].offset) : NULL)
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier#define PUSH_CONTAINER(m, new) (m)->container_offsets[(m)->n_containers ++] = (uint8_t*)(new) - (uint8_t*)(m)->hdr;
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer#define RTA_TYPE(rta) ((rta)->rta_type & NLA_TYPE_MASK)
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer#define RTA_FLAGS(rta) ((rta)->rta_type & ~NLA_TYPE_MASK)
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyerint message_new_empty(sd_netlink *rtnl, sd_netlink_message **ret) {
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer sd_netlink_message *m;
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer assert_return(ret, -EINVAL);
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer /* Note that 'rtnl' is currently unused, if we start using it internally
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer we must take care to avoid problems due to mutual references between
6b197f2a03fa03a2a853cf726d47be2ea4c623b6Harald Hoyer buses and their queued messages. See sd-bus.
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer */
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer m = new0(sd_netlink_message, 1);
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer if (!m)
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer return -ENOMEM;
5c404f1ab8e96efedb983806443ca982a1b2a372Evgeny Vereshchagin
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer m->n_ref = REFCNT_INIT;
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
c90feab4ff8bc23d88d4f9c67d9652ba189cb51bMichal Schmidt m->sealed = false;
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer *ret = m;
889a90422dd47284dffa32b9234a6e58991b000cRonny Chevalier
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer return 0;
0d6e798a784ef0ba6b95512e4453067b2f84a91aHarald Hoyer}
d9890f4ed47c0d565915360d8bae3b7a1428f285Harald Hoyer
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyerint message_new(sd_netlink *rtnl, sd_netlink_message **ret, uint16_t type) {
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer const NLType *nl_type;
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer size_t size;
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer int r;
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer r = type_system_get_type(&type_system_root, &nl_type, type);
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer if (r < 0)
898720b7e9cf3bdf7a93e435cbed5dd6942ecf9bHarald Hoyer return r;
if (type_get_type(nl_type) != NETLINK_TYPE_NESTED)
return -EINVAL;
r = message_new_empty(rtnl, &m);
if (r < 0)
return r;
size = NLMSG_SPACE(type_get_size(nl_type));
assert(size >= sizeof(struct nlmsghdr));
m->hdr = malloc0(size);
if (!m->hdr)
return -ENOMEM;
m->hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
type_get_type_system(nl_type, &m->containers[0].type_system);
m->hdr->nlmsg_len = size;
m->hdr->nlmsg_type = type;
*ret = m;
m = NULL;
return 0;
}
int sd_netlink_message_request_dump(sd_netlink_message *m, int dump) {
assert_return(m, -EINVAL);
assert_return(m->hdr, -EINVAL);
assert_return(m->hdr->nlmsg_type == RTM_GETLINK ||
m->hdr->nlmsg_type == RTM_GETADDR ||
m->hdr->nlmsg_type == RTM_GETROUTE ||
m->hdr->nlmsg_type == RTM_GETNEIGH,
-EINVAL);
if (dump)
m->hdr->nlmsg_flags |= NLM_F_DUMP;
else
m->hdr->nlmsg_flags &= ~NLM_F_DUMP;
return 0;
}
sd_netlink_message *sd_netlink_message_ref(sd_netlink_message *m) {
if (m)
assert_se(REFCNT_INC(m->n_ref) >= 2);
return m;
}
sd_netlink_message *sd_netlink_message_unref(sd_netlink_message *m) {
if (m && REFCNT_DEC(m->n_ref) == 0) {
unsigned i;
free(m->hdr);
for (i = 0; i <= m->n_containers; i++)
free(m->containers[i].attributes);
sd_netlink_message_unref(m->next);
free(m);
}
return NULL;
}
int sd_netlink_message_get_type(sd_netlink_message *m, uint16_t *type) {
assert_return(m, -EINVAL);
assert_return(type, -EINVAL);
*type = m->hdr->nlmsg_type;
return 0;
}
int sd_netlink_message_is_broadcast(sd_netlink_message *m) {
assert_return(m, -EINVAL);
return m->broadcast;
}
/* If successful the updated message will be correctly aligned, if
unsuccessful the old message is untouched. */
static int add_rtattr(sd_netlink_message *m, unsigned short type, const void *data, size_t data_length) {
uint32_t rta_length;
size_t message_length, padding_length;
struct nlmsghdr *new_hdr;
struct rtattr *rta;
char *padding;
unsigned i;
int offset;
assert(m);
assert(m->hdr);
assert(!m->sealed);
assert(NLMSG_ALIGN(m->hdr->nlmsg_len) == m->hdr->nlmsg_len);
assert(!data || data_length);
/* get offset of the new attribute */
offset = m->hdr->nlmsg_len;
/* get the size of the new rta attribute (with padding at the end) */
rta_length = RTA_LENGTH(data_length);
/* get the new message size (with padding at the end) */
message_length = offset + RTA_ALIGN(rta_length);
/* realloc to fit the new attribute */
new_hdr = realloc(m->hdr, message_length);
if (!new_hdr)
return -ENOMEM;
m->hdr = new_hdr;
/* get pointer to the attribute we are about to add */
rta = (struct rtattr *) ((uint8_t *) m->hdr + offset);
/* if we are inside containers, extend them */
for (i = 0; i < m->n_containers; i++)
GET_CONTAINER(m, i)->rta_len += message_length - offset;
/* fill in the attribute */
rta->rta_type = type;
rta->rta_len = rta_length;
if (data)
/* we don't deal with the case where the user lies about the type
* and gives us too little data (so don't do that)
*/
padding = mempcpy(RTA_DATA(rta), data, data_length);
else {
/* if no data was passed, make sure we still initialize the padding
note that we can have data_length > 0 (used by some containers) */
padding = RTA_DATA(rta);
}
/* make sure also the padding at the end of the message is initialized */
padding_length = (uint8_t*)m->hdr + message_length - (uint8_t*)padding;
memzero(padding, padding_length);
/* update message size */
m->hdr->nlmsg_len = message_length;
return offset;
}
static int message_attribute_has_type(sd_netlink_message *m, size_t *out_size, uint16_t attribute_type, uint16_t data_type) {
const NLType *type;
int r;
assert(m);
r = type_system_get_type(m->containers[m->n_containers].type_system, &type, attribute_type);
if (r < 0)
return r;
if (type_get_type(type) != data_type)
return -EINVAL;
if (out_size)
*out_size = type_get_size(type);
return 0;
}
int sd_netlink_message_append_string(sd_netlink_message *m, unsigned short type, const char *data) {
size_t length, size;
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
assert_return(data, -EINVAL);
r = message_attribute_has_type(m, &size, type, NETLINK_TYPE_STRING);
if (r < 0)
return r;
if (size) {
length = strnlen(data, size+1);
if (length > size)
return -EINVAL;
} else
length = strlen(data);
r = add_rtattr(m, type, data, length + 1);
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_flag(sd_netlink_message *m, unsigned short type) {
size_t size;
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
r = message_attribute_has_type(m, &size, type, NETLINK_TYPE_FLAG);
if (r < 0)
return r;
r = add_rtattr(m, type, NULL, 0);
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_u8(sd_netlink_message *m, unsigned short type, uint8_t data) {
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_U8);
if (r < 0)
return r;
r = add_rtattr(m, type, &data, sizeof(uint8_t));
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_u16(sd_netlink_message *m, unsigned short type, uint16_t data) {
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_U16);
if (r < 0)
return r;
r = add_rtattr(m, type, &data, sizeof(uint16_t));
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_u32(sd_netlink_message *m, unsigned short type, uint32_t data) {
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_U32);
if (r < 0)
return r;
r = add_rtattr(m, type, &data, sizeof(uint32_t));
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_in_addr(sd_netlink_message *m, unsigned short type, const struct in_addr *data) {
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
assert_return(data, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_IN_ADDR);
if (r < 0)
return r;
r = add_rtattr(m, type, data, sizeof(struct in_addr));
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_in6_addr(sd_netlink_message *m, unsigned short type, const struct in6_addr *data) {
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
assert_return(data, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_IN_ADDR);
if (r < 0)
return r;
r = add_rtattr(m, type, data, sizeof(struct in6_addr));
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_ether_addr(sd_netlink_message *m, unsigned short type, const struct ether_addr *data) {
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
assert_return(data, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_ETHER_ADDR);
if (r < 0)
return r;
r = add_rtattr(m, type, data, ETH_ALEN);
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_append_cache_info(sd_netlink_message *m, unsigned short type, const struct ifa_cacheinfo *info) {
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
assert_return(info, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_CACHE_INFO);
if (r < 0)
return r;
r = add_rtattr(m, type, info, sizeof(struct ifa_cacheinfo));
if (r < 0)
return r;
return 0;
}
int sd_netlink_message_open_container(sd_netlink_message *m, unsigned short type) {
size_t size;
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
assert_return(m->n_containers < RTNL_CONTAINER_DEPTH, -ERANGE);
r = message_attribute_has_type(m, &size, type, NETLINK_TYPE_NESTED);
if (r < 0) {
const NLTypeSystemUnion *type_system_union;
int family;
r = message_attribute_has_type(m, &size, type, NETLINK_TYPE_UNION);
if (r < 0)
return r;
r = sd_rtnl_message_get_family(m, &family);
if (r < 0)
return r;
r = type_system_get_type_system_union(m->containers[m->n_containers].type_system, &type_system_union, type);
if (r < 0)
return r;
r = type_system_union_protocol_get_type_system(type_system_union,
&m->containers[m->n_containers + 1].type_system,
family);
if (r < 0)
return r;
} else {
r = type_system_get_type_system(m->containers[m->n_containers].type_system,
&m->containers[m->n_containers + 1].type_system,
type);
if (r < 0)
return r;
}
r = add_rtattr(m, type | NLA_F_NESTED, NULL, size);
if (r < 0)
return r;
m->containers[m->n_containers ++].offset = r;
return 0;
}
int sd_netlink_message_open_container_union(sd_netlink_message *m, unsigned short type, const char *key) {
const NLTypeSystemUnion *type_system_union;
int r;
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
r = type_system_get_type_system_union(m->containers[m->n_containers].type_system, &type_system_union, type);
if (r < 0)
return r;
r = type_system_union_get_type_system(type_system_union,
&m->containers[m->n_containers + 1].type_system,
key);
if (r < 0)
return r;
r = sd_netlink_message_append_string(m, type_system_union->match, key);
if (r < 0)
return r;
/* do we evere need non-null size */
r = add_rtattr(m, type | NLA_F_NESTED, NULL, 0);
if (r < 0)
return r;
m->containers[m->n_containers ++].offset = r;
return 0;
}
int sd_netlink_message_close_container(sd_netlink_message *m) {
assert_return(m, -EINVAL);
assert_return(!m->sealed, -EPERM);
assert_return(m->n_containers > 0, -EINVAL);
m->containers[m->n_containers].type_system = NULL;
m->n_containers --;
return 0;
}
static int netlink_message_read_internal(sd_netlink_message *m, unsigned short type, void **data, bool *net_byteorder) {
struct netlink_attribute *attribute;
struct rtattr *rta;
assert_return(m, -EINVAL);
assert_return(m->sealed, -EPERM);
assert_return(data, -EINVAL);
assert(m->n_containers < RTNL_CONTAINER_DEPTH);
assert(m->containers[m->n_containers].attributes);
assert(type < m->containers[m->n_containers].n_attributes);
attribute = &m->containers[m->n_containers].attributes[type];
if(!attribute->offset)
return -ENODATA;
rta = (struct rtattr*)((uint8_t *) m->hdr + attribute->offset);
*data = RTA_DATA(rta);
if (net_byteorder)
*net_byteorder = attribute->net_byteorder;
return RTA_PAYLOAD(rta);
}
int sd_netlink_message_read_string(sd_netlink_message *m, unsigned short type, const char **data) {
int r;
void *attr_data;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_STRING);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, NULL);
if (r < 0)
return r;
else if (strnlen(attr_data, r) >= (size_t) r)
return -EIO;
if (data)
*data = (const char *) attr_data;
return 0;
}
int sd_netlink_message_read_u8(sd_netlink_message *m, unsigned short type, uint8_t *data) {
int r;
void *attr_data;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_U8);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, NULL);
if (r < 0)
return r;
else if ((size_t) r < sizeof(uint8_t))
return -EIO;
if (data)
*data = *(uint8_t *) attr_data;
return 0;
}
int sd_netlink_message_read_u16(sd_netlink_message *m, unsigned short type, uint16_t *data) {
void *attr_data;
bool net_byteorder;
int r;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_U16);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, &net_byteorder);
if (r < 0)
return r;
else if ((size_t) r < sizeof(uint16_t))
return -EIO;
if (data) {
if (net_byteorder)
*data = be16toh(*(uint16_t *) attr_data);
else
*data = *(uint16_t *) attr_data;
}
return 0;
}
int sd_netlink_message_read_u32(sd_netlink_message *m, unsigned short type, uint32_t *data) {
void *attr_data;
bool net_byteorder;
int r;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_U32);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, &net_byteorder);
if (r < 0)
return r;
else if ((size_t)r < sizeof(uint32_t))
return -EIO;
if (data) {
if (net_byteorder)
*data = be32toh(*(uint32_t *) attr_data);
else
*data = *(uint32_t *) attr_data;
}
return 0;
}
int sd_netlink_message_read_ether_addr(sd_netlink_message *m, unsigned short type, struct ether_addr *data) {
int r;
void *attr_data;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_ETHER_ADDR);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, NULL);
if (r < 0)
return r;
else if ((size_t)r < sizeof(struct ether_addr))
return -EIO;
if (data)
memcpy(data, attr_data, sizeof(struct ether_addr));
return 0;
}
int sd_netlink_message_read_cache_info(sd_netlink_message *m, unsigned short type, struct ifa_cacheinfo *info) {
int r;
void *attr_data;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_CACHE_INFO);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, NULL);
if (r < 0)
return r;
else if ((size_t)r < sizeof(struct ifa_cacheinfo))
return -EIO;
if (info)
memcpy(info, attr_data, sizeof(struct ifa_cacheinfo));
return 0;
}
int sd_netlink_message_read_in_addr(sd_netlink_message *m, unsigned short type, struct in_addr *data) {
int r;
void *attr_data;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_IN_ADDR);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, NULL);
if (r < 0)
return r;
else if ((size_t)r < sizeof(struct in_addr))
return -EIO;
if (data)
memcpy(data, attr_data, sizeof(struct in_addr));
return 0;
}
int sd_netlink_message_read_in6_addr(sd_netlink_message *m, unsigned short type, struct in6_addr *data) {
int r;
void *attr_data;
assert_return(m, -EINVAL);
r = message_attribute_has_type(m, NULL, type, NETLINK_TYPE_IN_ADDR);
if (r < 0)
return r;
r = netlink_message_read_internal(m, type, &attr_data, NULL);
if (r < 0)
return r;
else if ((size_t)r < sizeof(struct in6_addr))
return -EIO;
if (data)
memcpy(data, attr_data, sizeof(struct in6_addr));
return 0;
}
static int netlink_container_parse(sd_netlink_message *m,
struct netlink_container *container,
int count,
struct rtattr *rta,
unsigned int rt_len) {
_cleanup_free_ struct netlink_attribute *attributes = NULL;
attributes = new0(struct netlink_attribute, count);
if(!attributes)
return -ENOMEM;
for (; RTA_OK(rta, rt_len); rta = RTA_NEXT(rta, rt_len)) {
unsigned short type;
type = RTA_TYPE(rta);
/* if the kernel is newer than the headers we used
when building, we ignore out-of-range attributes */
if (type >= count)
continue;
if (attributes[type].offset)
log_debug("rtnl: message parse - overwriting repeated attribute");
attributes[type].offset = (uint8_t *) rta - (uint8_t *) m->hdr;
attributes[type].nested = RTA_FLAGS(rta) & NLA_F_NESTED;
attributes[type].net_byteorder = RTA_FLAGS(rta) & NLA_F_NET_BYTEORDER;
}
container->attributes = attributes;
attributes = NULL;
container->n_attributes = count;
return 0;
}
int sd_netlink_message_enter_container(sd_netlink_message *m, unsigned short type_id) {
const NLType *nl_type;
const NLTypeSystem *type_system;
void *container;
uint16_t type;
size_t size;
int r;
assert_return(m, -EINVAL);
assert_return(m->n_containers < RTNL_CONTAINER_DEPTH, -EINVAL);
r = type_system_get_type(m->containers[m->n_containers].type_system,
&nl_type,
type_id);
if (r < 0)
return r;
type = type_get_type(nl_type);
if (type == NETLINK_TYPE_NESTED) {
r = type_system_get_type_system(m->containers[m->n_containers].type_system,
&type_system,
type_id);
if (r < 0)
return r;
} else if (type == NETLINK_TYPE_UNION) {
const NLTypeSystemUnion *type_system_union;
r = type_system_get_type_system_union(m->containers[m->n_containers].type_system,
&type_system_union,
type_id);
if (r < 0)
return r;
switch (type_system_union->match_type) {
case NL_MATCH_SIBLING:
{
const char *key;
r = sd_netlink_message_read_string(m, type_system_union->match, &key);
if (r < 0)
return r;
r = type_system_union_get_type_system(type_system_union,
&type_system,
key);
if (r < 0)
return r;
break;
}
case NL_MATCH_PROTOCOL:
{
int family;
r = sd_rtnl_message_get_family(m, &family);
if (r < 0)
return r;
r = type_system_union_protocol_get_type_system(type_system_union,
&type_system,
family);
if (r < 0)
return r;
break;
}
default:
assert_not_reached("sd-netlink: invalid type system union type");
}
} else
return -EINVAL;
r = netlink_message_read_internal(m, type_id, &container, NULL);
if (r < 0)
return r;
else
size = (size_t)r;
m->n_containers ++;
r = netlink_container_parse(m,
&m->containers[m->n_containers],
type_system_get_count(type_system),
container,
size);
if (r < 0) {
m->n_containers --;
return r;
}
m->containers[m->n_containers].type_system = type_system;
return 0;
}
int sd_netlink_message_exit_container(sd_netlink_message *m) {
assert_return(m, -EINVAL);
assert_return(m->sealed, -EINVAL);
assert_return(m->n_containers > 0, -EINVAL);
free(m->containers[m->n_containers].attributes);
m->containers[m->n_containers].attributes = NULL;
m->containers[m->n_containers].type_system = NULL;
m->n_containers --;
return 0;
}
uint32_t rtnl_message_get_serial(sd_netlink_message *m) {
assert(m);
assert(m->hdr);
return m->hdr->nlmsg_seq;
}
int sd_netlink_message_is_error(sd_netlink_message *m) {
assert_return(m, 0);
assert_return(m->hdr, 0);
return m->hdr->nlmsg_type == NLMSG_ERROR;
}
int sd_netlink_message_get_errno(sd_netlink_message *m) {
struct nlmsgerr *err;
assert_return(m, -EINVAL);
assert_return(m->hdr, -EINVAL);
if (!sd_netlink_message_is_error(m))
return 0;
err = NLMSG_DATA(m->hdr);
return err->error;
}
int sd_netlink_message_rewind(sd_netlink_message *m) {
const NLType *nl_type;
uint16_t type;
size_t size;
unsigned i;
int r;
assert_return(m, -EINVAL);
/* don't allow appending to message once parsed */
if (!m->sealed)
rtnl_message_seal(m);
for (i = 1; i <= m->n_containers; i++) {
free(m->containers[i].attributes);
m->containers[i].attributes = NULL;
}
m->n_containers = 0;
if (m->containers[0].attributes) {
/* top-level attributes have already been parsed */
return 0;
}
assert(m->hdr);
r = type_system_get_type(&type_system_root, &nl_type, m->hdr->nlmsg_type);
if (r < 0)
return r;
type = type_get_type(nl_type);
size = type_get_size(nl_type);
if (type == NETLINK_TYPE_NESTED) {
const NLTypeSystem *type_system;
type_get_type_system(nl_type, &type_system);
m->containers[0].type_system = type_system;
r = netlink_container_parse(m,
&m->containers[m->n_containers],
type_system_get_count(type_system),
(struct rtattr*)((uint8_t*)NLMSG_DATA(m->hdr) + NLMSG_ALIGN(size)),
NLMSG_PAYLOAD(m->hdr, size));
if (r < 0)
return r;
}
return 0;
}
void rtnl_message_seal(sd_netlink_message *m) {
assert(m);
assert(!m->sealed);
m->sealed = true;
}
sd_netlink_message *sd_netlink_message_next(sd_netlink_message *m) {
assert_return(m, NULL);
return m->next;
}