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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:14:35 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-09 13:14:35 +0000
commit9b8a97db9ec4b795e29e72289005fbc58484ebeb (patch)
treee24ca2d68215e57b4759fe5c032629821eabb250 /lib/mnl_utils.c
parentInitial commit. (diff)
downloadiproute2-9b8a97db9ec4b795e29e72289005fbc58484ebeb.tar.xz
iproute2-9b8a97db9ec4b795e29e72289005fbc58484ebeb.zip
Adding upstream version 6.8.0.upstream/6.8.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--lib/mnl_utils.c376
1 files changed, 376 insertions, 0 deletions
diff --git a/lib/mnl_utils.c b/lib/mnl_utils.c
new file mode 100644
index 0000000..af5aa4f
--- /dev/null
+++ b/lib/mnl_utils.c
@@ -0,0 +1,376 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * mnl_utils.c Helpers for working with libmnl.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <libmnl/libmnl.h>
+#include <linux/genetlink.h>
+
+#include "libnetlink.h"
+#include "mnl_utils.h"
+#include "utils.h"
+
+struct mnl_socket *mnlu_socket_open(int bus)
+{
+ struct mnl_socket *nl;
+ int one = 1;
+
+ nl = mnl_socket_open(bus);
+ if (nl == NULL)
+ return NULL;
+
+ mnl_socket_setsockopt(nl, NETLINK_CAP_ACK, &one, sizeof(one));
+ mnl_socket_setsockopt(nl, NETLINK_EXT_ACK, &one, sizeof(one));
+
+ if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0)
+ goto err_bind;
+
+ return nl;
+
+err_bind:
+ mnl_socket_close(nl);
+ return NULL;
+}
+
+struct nlmsghdr *mnlu_msg_prepare(void *buf, uint32_t nlmsg_type, uint16_t flags,
+ void *extra_header, size_t extra_header_size)
+{
+ struct nlmsghdr *nlh;
+ void *eh;
+
+ nlh = mnl_nlmsg_put_header(buf);
+ nlh->nlmsg_type = nlmsg_type;
+ nlh->nlmsg_flags = flags;
+ nlh->nlmsg_seq = time(NULL);
+
+ eh = mnl_nlmsg_put_extra_header(nlh, extra_header_size);
+ memcpy(eh, extra_header, extra_header_size);
+
+ return nlh;
+}
+
+static int mnlu_cb_noop(const struct nlmsghdr *nlh, void *data)
+{
+ return MNL_CB_OK;
+}
+
+static int mnlu_cb_error(const struct nlmsghdr *nlh, void *data)
+{
+ const struct nlmsgerr *err = mnl_nlmsg_get_payload(nlh);
+
+ if (mnl_nlmsg_get_payload_len(nlh) < sizeof(*err))
+ return MNL_CB_STOP;
+ /* Netlink subsystems returns the errno value with different signess */
+ if (err->error < 0)
+ errno = -err->error;
+ else
+ errno = err->error;
+
+ if (nl_dump_ext_ack(nlh, NULL))
+ return MNL_CB_ERROR;
+
+ return err->error == 0 ? MNL_CB_STOP : MNL_CB_ERROR;
+}
+
+static int mnlu_cb_stop(const struct nlmsghdr *nlh, void *data)
+{
+ int len;
+
+ if (mnl_nlmsg_get_payload_len(nlh) < sizeof(len))
+ return MNL_CB_STOP;
+ len = *(int *)mnl_nlmsg_get_payload(nlh);
+ if (len < 0) {
+ errno = -len;
+ nl_dump_ext_ack_done(nlh, sizeof(int), len);
+ return MNL_CB_ERROR;
+ }
+ return MNL_CB_STOP;
+}
+
+static mnl_cb_t mnlu_cb_array[NLMSG_MIN_TYPE] = {
+ [NLMSG_NOOP] = mnlu_cb_noop,
+ [NLMSG_ERROR] = mnlu_cb_error,
+ [NLMSG_DONE] = mnlu_cb_stop,
+ [NLMSG_OVERRUN] = mnlu_cb_noop,
+};
+
+int mnlu_socket_recv_run(struct mnl_socket *nl, unsigned int seq, void *buf, size_t buf_size,
+ mnl_cb_t cb, void *data)
+{
+ unsigned int portid = mnl_socket_get_portid(nl);
+ int err;
+
+ do {
+ err = mnl_socket_recvfrom(nl, buf, buf_size);
+ if (err <= 0)
+ break;
+ err = mnl_cb_run2(buf, err, seq, portid,
+ cb, data, mnlu_cb_array,
+ ARRAY_SIZE(mnlu_cb_array));
+ } while (err > 0);
+
+ return err;
+}
+
+static int ctrl_attrs_cb(const struct nlattr *attr, void *data)
+{
+ int type = mnl_attr_get_type(attr);
+ const struct nlattr **tb = data;
+
+ if (mnl_attr_type_valid(attr, CTRL_ATTR_MAX) < 0)
+ return MNL_CB_ERROR;
+
+ if (type == CTRL_ATTR_FAMILY_ID &&
+ mnl_attr_validate(attr, MNL_TYPE_U16) < 0)
+ return MNL_CB_ERROR;
+ if (type == CTRL_ATTR_MAXATTR &&
+ mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+ return MNL_CB_ERROR;
+ if (type == CTRL_ATTR_POLICY &&
+ mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
+ return MNL_CB_ERROR;
+ if (type == CTRL_ATTR_OP_POLICY &&
+ mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
+ return MNL_CB_ERROR;
+ tb[type] = attr;
+ return MNL_CB_OK;
+}
+
+static int get_family_cb(const struct nlmsghdr *nlh, void *data)
+{
+ struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
+ struct nlattr *tb[CTRL_ATTR_MAX + 1] = {};
+ struct mnlu_gen_socket *nlg = data;
+
+ mnl_attr_parse(nlh, sizeof(*genl), ctrl_attrs_cb, tb);
+ if (!tb[CTRL_ATTR_FAMILY_ID])
+ return MNL_CB_ERROR;
+ if (!tb[CTRL_ATTR_MAXATTR])
+ return MNL_CB_ERROR;
+ nlg->family = mnl_attr_get_u16(tb[CTRL_ATTR_FAMILY_ID]);
+ nlg->maxattr = mnl_attr_get_u32(tb[CTRL_ATTR_MAXATTR]);
+ return MNL_CB_OK;
+}
+
+static int family_get(struct mnlu_gen_socket *nlg, const char *family_name)
+{
+ struct genlmsghdr hdr = {};
+ struct nlmsghdr *nlh;
+ int err;
+
+ hdr.cmd = CTRL_CMD_GETFAMILY;
+ hdr.version = 0x1;
+
+ nlh = mnlu_msg_prepare(nlg->buf, GENL_ID_CTRL,
+ NLM_F_REQUEST | NLM_F_ACK,
+ &hdr, sizeof(hdr));
+
+ mnl_attr_put_strz(nlh, CTRL_ATTR_FAMILY_NAME, family_name);
+
+ err = mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
+ if (err < 0)
+ return err;
+
+ err = mnlu_socket_recv_run(nlg->nl, nlh->nlmsg_seq, nlg->buf,
+ MNL_SOCKET_BUFFER_SIZE,
+ get_family_cb, nlg);
+ return err;
+}
+
+int mnlu_gen_socket_open(struct mnlu_gen_socket *nlg, const char *family_name,
+ uint8_t version)
+{
+ int err;
+
+ nlg->buf = malloc(MNL_SOCKET_BUFFER_SIZE);
+ if (!nlg->buf)
+ goto err_buf_alloc;
+
+ nlg->nl = mnlu_socket_open(NETLINK_GENERIC);
+ if (!nlg->nl)
+ goto err_socket_open;
+
+ err = family_get(nlg, family_name);
+ if (err)
+ goto err_socket;
+
+ return 0;
+
+err_socket:
+ mnl_socket_close(nlg->nl);
+err_socket_open:
+ free(nlg->buf);
+err_buf_alloc:
+ return -1;
+}
+
+void mnlu_gen_socket_close(struct mnlu_gen_socket *nlg)
+{
+ mnl_socket_close(nlg->nl);
+ free(nlg->buf);
+}
+
+struct nlmsghdr *
+_mnlu_gen_socket_cmd_prepare(struct mnlu_gen_socket *nlg,
+ uint8_t cmd, uint16_t flags,
+ uint32_t id, uint8_t version)
+{
+ struct genlmsghdr hdr = {};
+ struct nlmsghdr *nlh;
+
+ hdr.cmd = cmd;
+ hdr.version = version;
+ nlh = mnlu_msg_prepare(nlg->buf, id, flags, &hdr, sizeof(hdr));
+ nlg->seq = nlh->nlmsg_seq;
+ return nlh;
+}
+
+struct nlmsghdr *mnlu_gen_socket_cmd_prepare(struct mnlu_gen_socket *nlg,
+ uint8_t cmd, uint16_t flags)
+{
+ return _mnlu_gen_socket_cmd_prepare(nlg, cmd, flags, nlg->family,
+ nlg->version);
+}
+
+int mnlu_gen_socket_sndrcv(struct mnlu_gen_socket *nlg, const struct nlmsghdr *nlh,
+ mnl_cb_t data_cb, void *data)
+{
+ int err;
+
+ err = mnl_socket_sendto(nlg->nl, nlh, nlh->nlmsg_len);
+ if (err < 0) {
+ perror("Failed to send data");
+ return -errno;
+ }
+
+ err = mnlu_socket_recv_run(nlg->nl, nlh->nlmsg_seq, nlg->buf,
+ MNL_SOCKET_BUFFER_SIZE,
+ data_cb, data);
+ if (err < 0) {
+ fprintf(stderr, "kernel answers: %s\n", strerror(errno));
+ return -errno;
+ }
+ return 0;
+}
+
+int mnlu_gen_socket_recv_run(struct mnlu_gen_socket *nlg, mnl_cb_t cb,
+ void *data)
+{
+ return mnlu_socket_recv_run(nlg->nl, nlg->seq, nlg->buf,
+ MNL_SOCKET_BUFFER_SIZE,
+ cb, data);
+}
+
+static int ctrl_policy_attrs_cb(const struct nlattr *attr, void *data)
+{
+ int type = mnl_attr_get_type(attr);
+ const struct nlattr **tb = data;
+
+ if (mnl_attr_type_valid(attr, CTRL_ATTR_POLICY_DUMP_MAX) < 0)
+ return MNL_CB_ERROR;
+
+ if (type == CTRL_ATTR_POLICY_DO &&
+ mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+ return MNL_CB_ERROR;
+ if (type == CTRL_ATTR_POLICY_DUMP &&
+ mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+ return MNL_CB_ERROR;
+
+ tb[type] = attr;
+ return MNL_CB_OK;
+}
+
+struct cmd_dump_policy_ctx {
+ uint8_t cmd;
+ uint8_t do_policy_idx_found:1,
+ dump_policy_idx_found:1;
+ uint32_t do_policy_idx;
+ uint32_t dump_policy_idx;
+ uint32_t dump_policy_attr_count;
+};
+
+static void process_dump_op_policy_nest(const struct nlattr *op_policy_nest,
+ struct cmd_dump_policy_ctx *ctx)
+{
+ struct nlattr *tb[CTRL_ATTR_POLICY_DUMP_MAX + 1] = {};
+ const struct nlattr *attr;
+ int err;
+
+ mnl_attr_for_each_nested(attr, op_policy_nest) {
+ if (ctx->cmd != (attr->nla_type & ~NLA_F_NESTED))
+ continue;
+ err = mnl_attr_parse_nested(attr, ctrl_policy_attrs_cb, tb);
+ if (err != MNL_CB_OK)
+ continue;
+ if (tb[CTRL_ATTR_POLICY_DO]) {
+ ctx->do_policy_idx = mnl_attr_get_u32(tb[CTRL_ATTR_POLICY_DO]);
+ ctx->do_policy_idx_found = true;
+ }
+ if (tb[CTRL_ATTR_POLICY_DUMP]) {
+ ctx->dump_policy_idx = mnl_attr_get_u32(tb[CTRL_ATTR_POLICY_DUMP]);
+ ctx->dump_policy_idx_found = true;
+ }
+ break;
+ }
+}
+
+static void process_dump_policy_nest(const struct nlattr *policy_nest,
+ struct cmd_dump_policy_ctx *ctx)
+{
+ const struct nlattr *attr;
+
+ if (!ctx->dump_policy_idx_found)
+ return;
+
+ mnl_attr_for_each_nested(attr, policy_nest)
+ if (ctx->dump_policy_idx == (attr->nla_type & ~NLA_F_NESTED))
+ ctx->dump_policy_attr_count++;
+}
+
+static int cmd_dump_policy_cb(const struct nlmsghdr *nlh, void *data)
+{
+ struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
+ struct nlattr *tb[CTRL_ATTR_MAX + 1] = {};
+ struct cmd_dump_policy_ctx *ctx = data;
+
+ mnl_attr_parse(nlh, sizeof(*genl), ctrl_attrs_cb, tb);
+ if (!tb[CTRL_ATTR_FAMILY_ID])
+ return MNL_CB_OK;
+
+ if (tb[CTRL_ATTR_OP_POLICY])
+ process_dump_op_policy_nest(tb[CTRL_ATTR_OP_POLICY], ctx);
+
+ if (tb[CTRL_ATTR_POLICY])
+ process_dump_policy_nest(tb[CTRL_ATTR_POLICY], ctx);
+
+ return MNL_CB_OK;
+}
+
+int mnlu_gen_cmd_dump_policy(struct mnlu_gen_socket *nlg, uint8_t cmd)
+{
+ struct cmd_dump_policy_ctx ctx = {
+ .cmd = cmd,
+ };
+ struct nlmsghdr *nlh;
+ int err;
+
+ nlh = _mnlu_gen_socket_cmd_prepare(nlg, CTRL_CMD_GETPOLICY,
+ NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP,
+ GENL_ID_CTRL, 1);
+
+ mnl_attr_put_u16(nlh, CTRL_ATTR_FAMILY_ID, nlg->family);
+
+ err = mnlu_gen_socket_sndrcv(nlg, nlh, cmd_dump_policy_cb, &ctx);
+ if (err)
+ return err;
+
+ if (!ctx.dump_policy_idx_found || !ctx.do_policy_idx_found ||
+ ctx.do_policy_idx == ctx.dump_policy_idx ||
+ !ctx.dump_policy_attr_count)
+ return -ENOTSUP;
+
+ return 0;
+}