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Diffstat (limited to 'src/libsystemd/src/sd-netlink/netlink-message.c')
-rw-r--r--src/libsystemd/src/sd-netlink/netlink-message.c963
1 files changed, 963 insertions, 0 deletions
diff --git a/src/libsystemd/src/sd-netlink/netlink-message.c b/src/libsystemd/src/sd-netlink/netlink-message.c
new file mode 100644
index 0000000000..73afe876b6
--- /dev/null
+++ b/src/libsystemd/src/sd-netlink/netlink-message.c
@@ -0,0 +1,963 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2013 Tom Gundersen <teg@jklm.no>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <netinet/in.h>
+#include <stdbool.h>
+#include <unistd.h>
+
+#include "systemd-basic/alloc-util.h"
+#include "systemd-basic/formats-util.h"
+#include "systemd-basic/missing.h"
+#include "systemd-basic/refcnt.h"
+#include "systemd-basic/socket-util.h"
+#include "systemd-basic/util.h"
+#include "systemd-staging/sd-netlink.h"
+
+#include "netlink-internal.h"
+#include "netlink-types.h"
+#include "netlink-util.h"
+
+#define GET_CONTAINER(m, i) ((i) < (m)->n_containers ? (struct rtattr*)((uint8_t*)(m)->hdr + (m)->containers[i].offset) : NULL)
+#define PUSH_CONTAINER(m, new) (m)->container_offsets[(m)->n_containers++] = (uint8_t*)(new) - (uint8_t*)(m)->hdr;
+
+#define RTA_TYPE(rta) ((rta)->rta_type & NLA_TYPE_MASK)
+#define RTA_FLAGS(rta) ((rta)->rta_type & ~NLA_TYPE_MASK)
+
+int message_new_empty(sd_netlink *rtnl, sd_netlink_message **ret) {
+ sd_netlink_message *m;
+
+ assert_return(ret, -EINVAL);
+
+ /* Note that 'rtnl' is currently unused, if we start using it internally
+ we must take care to avoid problems due to mutual references between
+ buses and their queued messages. See sd-bus.
+ */
+
+ m = new0(sd_netlink_message, 1);
+ if (!m)
+ return -ENOMEM;
+
+ m->n_ref = REFCNT_INIT;
+
+ m->sealed = false;
+
+ *ret = m;
+
+ return 0;
+}
+
+int message_new(sd_netlink *rtnl, sd_netlink_message **ret, uint16_t type) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ const NLType *nl_type;
+ size_t size;
+ int r;
+
+ r = type_system_get_type(&type_system_root, &nl_type, type);
+ if (r < 0)
+ 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);
+
+ SET_FLAG(m->hdr->nlmsg_flags, NLM_F_DUMP, 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) {
+ sd_netlink_message *t;
+
+ while (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);
+
+ t = m;
+ m = m->next;
+ free(t);
+ }
+
+ 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_set_flags(sd_netlink_message *m, uint16_t flags) {
+ assert_return(m, -EINVAL);
+ assert_return(flags, -EINVAL);
+
+ m->hdr->nlmsg_flags = flags;
+
+ 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_data(sd_netlink_message *m, unsigned short type, const void *data, size_t len) {
+ int r;
+
+ assert_return(m, -EINVAL);
+ assert_return(!m->sealed, -EPERM);
+
+ r = add_rtattr(m, type, data, len);
+ 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);
+
+ m->containers[m->n_containers].attributes = mfree(m->containers[m->n_containers].attributes);
+ 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++)
+ m->containers[i].attributes = mfree(m->containers[i].attributes);
+
+ 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;
+}