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Diffstat (limited to 'src/libsystemd/sd-netlink/netlink-message-nfnl.c')
-rw-r--r--src/libsystemd/sd-netlink/netlink-message-nfnl.c420
1 files changed, 420 insertions, 0 deletions
diff --git a/src/libsystemd/sd-netlink/netlink-message-nfnl.c b/src/libsystemd/sd-netlink/netlink-message-nfnl.c
new file mode 100644
index 0000000..55287d4
--- /dev/null
+++ b/src/libsystemd/sd-netlink/netlink-message-nfnl.c
@@ -0,0 +1,420 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <netinet/in.h>
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nf_tables.h>
+#include <linux/netfilter.h>
+
+#include "sd-netlink.h"
+
+#include "io-util.h"
+#include "netlink-internal.h"
+#include "netlink-types.h"
+#include "netlink-util.h"
+
+static bool nfproto_is_valid(int nfproto) {
+ return IN_SET(nfproto,
+ NFPROTO_UNSPEC,
+ NFPROTO_INET,
+ NFPROTO_IPV4,
+ NFPROTO_ARP,
+ NFPROTO_NETDEV,
+ NFPROTO_BRIDGE,
+ NFPROTO_IPV6,
+ NFPROTO_DECNET);
+}
+
+int sd_nfnl_message_new(sd_netlink *nfnl, sd_netlink_message **ret, int nfproto, uint16_t subsys, uint16_t msg_type, uint16_t flags) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ assert_return(nfnl, -EINVAL);
+ assert_return(ret, -EINVAL);
+ assert_return(nfproto_is_valid(nfproto), -EINVAL);
+ assert_return(NFNL_MSG_TYPE(msg_type) == msg_type, -EINVAL);
+
+ r = message_new(nfnl, &m, subsys << 8 | msg_type);
+ if (r < 0)
+ return r;
+
+ m->hdr->nlmsg_flags |= flags;
+
+ *(struct nfgenmsg*) NLMSG_DATA(m->hdr) = (struct nfgenmsg) {
+ .nfgen_family = nfproto,
+ .version = NFNETLINK_V0,
+ };
+
+ *ret = TAKE_PTR(m);
+ return 0;
+}
+
+static int nfnl_message_set_res_id(sd_netlink_message *m, uint16_t res_id) {
+ struct nfgenmsg *nfgen;
+
+ assert(m);
+ assert(m->hdr);
+
+ nfgen = NLMSG_DATA(m->hdr);
+ nfgen->res_id = htobe16(res_id);
+
+ return 0;
+}
+
+static int nfnl_message_get_subsys(sd_netlink_message *m, uint16_t *ret) {
+ uint16_t t;
+ int r;
+
+ assert(m);
+ assert(ret);
+
+ r = sd_netlink_message_get_type(m, &t);
+ if (r < 0)
+ return r;
+
+ *ret = NFNL_SUBSYS_ID(t);
+ return 0;
+}
+
+static int nfnl_message_new_batch(sd_netlink *nfnl, sd_netlink_message **ret, uint16_t subsys, uint16_t msg_type) {
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ assert_return(nfnl, -EINVAL);
+ assert_return(ret, -EINVAL);
+ assert_return(NFNL_MSG_TYPE(msg_type) == msg_type, -EINVAL);
+
+ r = sd_nfnl_message_new(nfnl, &m, NFPROTO_UNSPEC, NFNL_SUBSYS_NONE, msg_type, 0);
+ if (r < 0)
+ return r;
+
+ r = nfnl_message_set_res_id(m, subsys);
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(m);
+ return 0;
+}
+
+int sd_nfnl_send_batch(
+ sd_netlink *nfnl,
+ sd_netlink_message **messages,
+ size_t n_messages,
+ uint32_t **ret_serials) {
+
+ /* iovs refs batch_begin and batch_end, hence, free iovs first, then free batch_begin and batch_end. */
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *batch_begin = NULL, *batch_end = NULL;
+ _cleanup_free_ struct iovec *iovs = NULL;
+ _cleanup_free_ uint32_t *serials = NULL;
+ uint16_t subsys;
+ ssize_t k;
+ size_t c = 0;
+ int r;
+
+ assert_return(nfnl, -EINVAL);
+ assert_return(!netlink_pid_changed(nfnl), -ECHILD);
+ assert_return(messages, -EINVAL);
+ assert_return(n_messages > 0, -EINVAL);
+
+ iovs = new(struct iovec, n_messages + 2);
+ if (!iovs)
+ return -ENOMEM;
+
+ if (ret_serials) {
+ serials = new(uint32_t, n_messages);
+ if (!serials)
+ return -ENOMEM;
+ }
+
+ r = nfnl_message_get_subsys(messages[0], &subsys);
+ if (r < 0)
+ return r;
+
+ r = nfnl_message_new_batch(nfnl, &batch_begin, subsys, NFNL_MSG_BATCH_BEGIN);
+ if (r < 0)
+ return r;
+
+ netlink_seal_message(nfnl, batch_begin);
+ iovs[c++] = IOVEC_MAKE(batch_begin->hdr, batch_begin->hdr->nlmsg_len);
+
+ for (size_t i = 0; i < n_messages; i++) {
+ uint16_t s;
+
+ r = nfnl_message_get_subsys(messages[i], &s);
+ if (r < 0)
+ return r;
+
+ if (s != subsys)
+ return -EINVAL;
+
+ netlink_seal_message(nfnl, messages[i]);
+ if (serials)
+ serials[i] = message_get_serial(messages[i]);
+
+ /* It seems that the kernel accepts an arbitrary number. Let's set the lower 16 bits of the
+ * serial of the first message. */
+ nfnl_message_set_res_id(messages[i], (uint16_t) (message_get_serial(batch_begin) & UINT16_MAX));
+
+ iovs[c++] = IOVEC_MAKE(messages[i]->hdr, messages[i]->hdr->nlmsg_len);
+ }
+
+ r = nfnl_message_new_batch(nfnl, &batch_end, subsys, NFNL_MSG_BATCH_END);
+ if (r < 0)
+ return r;
+
+ netlink_seal_message(nfnl, batch_end);
+ iovs[c++] = IOVEC_MAKE(batch_end->hdr, batch_end->hdr->nlmsg_len);
+
+ assert(c == n_messages + 2);
+ k = writev(nfnl->fd, iovs, n_messages + 2);
+ if (k < 0)
+ return -errno;
+
+ if (ret_serials)
+ *ret_serials = TAKE_PTR(serials);
+
+ return 0;
+}
+
+int sd_nfnl_call_batch(
+ sd_netlink *nfnl,
+ sd_netlink_message **messages,
+ size_t n_messages,
+ uint64_t usec,
+ sd_netlink_message ***ret_messages) {
+
+ _cleanup_free_ sd_netlink_message **replies = NULL;
+ _cleanup_free_ uint32_t *serials = NULL;
+ int k, r;
+
+ assert_return(nfnl, -EINVAL);
+ assert_return(!netlink_pid_changed(nfnl), -ECHILD);
+ assert_return(messages, -EINVAL);
+ assert_return(n_messages > 0, -EINVAL);
+
+ if (ret_messages) {
+ replies = new0(sd_netlink_message*, n_messages);
+ if (!replies)
+ return -ENOMEM;
+ }
+
+ r = sd_nfnl_send_batch(nfnl, messages, n_messages, &serials);
+ if (r < 0)
+ return r;
+
+ for (size_t i = 0; i < n_messages; i++) {
+ k = sd_netlink_read(nfnl, serials[i], usec, ret_messages ? replies + i : NULL);
+ if (k < 0 && r >= 0)
+ r = k;
+ }
+ if (r < 0)
+ return r;
+
+ if (ret_messages)
+ *ret_messages = TAKE_PTR(replies);
+
+ return 0;
+}
+
+int sd_nfnl_nft_message_new_basechain(
+ sd_netlink *nfnl,
+ sd_netlink_message **ret,
+ int nfproto,
+ const char *table,
+ const char *chain,
+ const char *type,
+ uint8_t hook,
+ int prio) {
+
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ r = sd_nfnl_message_new(nfnl, &m, nfproto, NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWCHAIN, NLM_F_CREATE);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_CHAIN_TABLE, table);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_CHAIN_NAME, chain);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_CHAIN_TYPE, type);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_open_container(m, NFTA_CHAIN_HOOK);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_u32(m, NFTA_HOOK_HOOKNUM, htobe32(hook));
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_u32(m, NFTA_HOOK_PRIORITY, htobe32(prio));
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_close_container(m);
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(m);
+ return 0;
+}
+
+int sd_nfnl_nft_message_new_table(
+ sd_netlink *nfnl,
+ sd_netlink_message **ret,
+ int nfproto,
+ const char *table) {
+
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ r = sd_nfnl_message_new(nfnl, &m, nfproto, NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWTABLE, NLM_F_CREATE | NLM_F_EXCL);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_TABLE_NAME, table);
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(m);
+ return r;
+}
+
+int sd_nfnl_nft_message_new_rule(
+ sd_netlink *nfnl,
+ sd_netlink_message **ret,
+ int nfproto,
+ const char *table,
+ const char *chain) {
+
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ r = sd_nfnl_message_new(nfnl, &m, nfproto, NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWRULE, NLM_F_CREATE);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_RULE_TABLE, table);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_RULE_CHAIN, chain);
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(m);
+ return r;
+}
+
+int sd_nfnl_nft_message_new_set(
+ sd_netlink *nfnl,
+ sd_netlink_message **ret,
+ int nfproto,
+ const char *table,
+ const char *set_name,
+ uint32_t set_id,
+ uint32_t klen) {
+
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ r = sd_nfnl_message_new(nfnl, &m, nfproto, NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWSET, NLM_F_CREATE);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_SET_TABLE, table);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_SET_NAME, set_name);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_u32(m, NFTA_SET_ID, ++set_id);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_u32(m, NFTA_SET_KEY_LEN, htobe32(klen));
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(m);
+ return r;
+}
+
+int sd_nfnl_nft_message_new_setelems(
+ sd_netlink *nfnl,
+ sd_netlink_message **ret,
+ int add, /* boolean */
+ int nfproto,
+ const char *table,
+ const char *set_name) {
+
+ _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+ int r;
+
+ if (add)
+ r = sd_nfnl_message_new(nfnl, &m, nfproto, NFNL_SUBSYS_NFTABLES, NFT_MSG_NEWSETELEM, NLM_F_CREATE);
+ else
+ r = sd_nfnl_message_new(nfnl, &m, nfproto, NFNL_SUBSYS_NFTABLES, NFT_MSG_DELSETELEM, 0);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_SET_ELEM_LIST_TABLE, table);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_string(m, NFTA_SET_ELEM_LIST_SET, set_name);
+ if (r < 0)
+ return r;
+
+ *ret = TAKE_PTR(m);
+ return r;
+}
+
+int sd_nfnl_nft_message_append_setelem(
+ sd_netlink_message *m,
+ uint32_t index,
+ const void *key,
+ size_t key_len,
+ const void *data,
+ size_t data_len,
+ uint32_t flags) {
+
+ int r;
+
+ r = sd_netlink_message_open_array(m, index);
+ if (r < 0)
+ return r;
+
+ r = sd_netlink_message_append_container_data(m, NFTA_SET_ELEM_KEY, NFTA_DATA_VALUE, key, key_len);
+ if (r < 0)
+ goto cancel;
+
+ if (data) {
+ r = sd_netlink_message_append_container_data(m, NFTA_SET_ELEM_DATA, NFTA_DATA_VALUE, data, data_len);
+ if (r < 0)
+ goto cancel;
+ }
+
+ if (flags != 0) {
+ r = sd_netlink_message_append_u32(m, NFTA_SET_ELEM_FLAGS, htobe32(flags));
+ if (r < 0)
+ goto cancel;
+ }
+
+ return sd_netlink_message_close_container(m); /* array */
+
+cancel:
+ (void) sd_netlink_message_cancel_array(m);
+ return r;
+}
+
+int sd_nfnl_socket_open(sd_netlink **ret) {
+ return netlink_open_family(ret, NETLINK_NETFILTER);
+}
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