summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJakub Kicinski <kuba@kernel.org>2020-10-03 10:44:46 +0200
committerDavid S. Miller <davem@davemloft.net>2020-10-03 14:18:29 -0700
commite992a6eda9a1eeeab73a8d2792464e4a2b1ebc3b (patch)
tree292af9635b3bb0714677337afc0effaff69d0406
parent50a896cf2d6f34e884a00139d6e6012c9833ace3 (diff)
genetlink: allow dumping command-specific policy
Right now CTRL_CMD_GETPOLICY can only dump the family-wide policy. Support dumping policy of a specific op. v3: - rebase after per-op policy export and handle that v2: - make cmd U32, just in case. v1: - don't echo op in the output in a naive way, this should make it cleaner to extend the output format for dumping policies for all the commands at once in the future. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/r/20201001225933.1373426-11-kuba@kernel.org Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--include/uapi/linux/genetlink.h1
-rw-r--r--net/netlink/genetlink.c41
2 files changed, 37 insertions, 5 deletions
diff --git a/include/uapi/linux/genetlink.h b/include/uapi/linux/genetlink.h
index bc9c98e84828..d83f214b4134 100644
--- a/include/uapi/linux/genetlink.h
+++ b/include/uapi/linux/genetlink.h
@@ -65,6 +65,7 @@ enum {
CTRL_ATTR_MCAST_GROUPS,
CTRL_ATTR_POLICY,
CTRL_ATTR_OP_POLICY,
+ CTRL_ATTR_OP,
__CTRL_ATTR_MAX,
};
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index eb916c44884f..c992424e4d63 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -123,7 +123,7 @@ static void genl_op_from_full(const struct genl_family *family,
op->policy = family->policy;
}
-static int genl_get_cmd_full(u8 cmd, const struct genl_family *family,
+static int genl_get_cmd_full(u32 cmd, const struct genl_family *family,
struct genl_ops *op)
{
int i;
@@ -152,7 +152,7 @@ static void genl_op_from_small(const struct genl_family *family,
op->policy = family->policy;
}
-static int genl_get_cmd_small(u8 cmd, const struct genl_family *family,
+static int genl_get_cmd_small(u32 cmd, const struct genl_family *family,
struct genl_ops *op)
{
int i;
@@ -166,7 +166,7 @@ static int genl_get_cmd_small(u8 cmd, const struct genl_family *family,
return -ENOENT;
}
-static int genl_get_cmd(u8 cmd, const struct genl_family *family,
+static int genl_get_cmd(u32 cmd, const struct genl_family *family,
struct genl_ops *op)
{
if (!genl_get_cmd_full(cmd, family, op))
@@ -1114,14 +1114,17 @@ struct ctrl_dump_policy_ctx {
struct netlink_policy_dump_state *state;
const struct genl_family *rt;
unsigned int opidx;
+ u32 op;
u16 fam_id;
- u8 policies:1;
+ u8 policies:1,
+ single_op:1;
};
static const struct nla_policy ctrl_policy_policy[] = {
[CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 },
[CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING,
.len = GENL_NAMSIZ - 1 },
+ [CTRL_ATTR_OP] = { .type = NLA_U32 },
};
static int ctrl_dumppolicy_start(struct netlink_callback *cb)
@@ -1154,6 +1157,23 @@ static int ctrl_dumppolicy_start(struct netlink_callback *cb)
ctx->rt = rt;
+ if (tb[CTRL_ATTR_OP]) {
+ ctx->single_op = true;
+ ctx->op = nla_get_u32(tb[CTRL_ATTR_OP]);
+
+ err = genl_get_cmd(ctx->op, rt, &op);
+ if (err) {
+ NL_SET_BAD_ATTR(cb->extack, tb[CTRL_ATTR_OP]);
+ return err;
+ }
+
+ if (!op.policy)
+ return -ENODATA;
+
+ return netlink_policy_dump_add_policy(&ctx->state, op.policy,
+ op.maxattr);
+ }
+
for (i = 0; i < genl_get_cmd_cnt(rt); i++) {
genl_get_cmd_by_index(i, rt, &op);
@@ -1248,7 +1268,18 @@ static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb)
while (ctx->opidx < genl_get_cmd_cnt(ctx->rt)) {
struct genl_ops op;
- genl_get_cmd_by_index(ctx->opidx, ctx->rt, &op);
+ if (ctx->single_op) {
+ int err;
+
+ err = genl_get_cmd(ctx->op, ctx->rt, &op);
+ if (WARN_ON(err))
+ return skb->len;
+
+ /* break out of the loop after this one */
+ ctx->opidx = genl_get_cmd_cnt(ctx->rt);
+ } else {
+ genl_get_cmd_by_index(ctx->opidx, ctx->rt, &op);
+ }
if (ctrl_dumppolicy_put_op(skb, cb, &op))
return skb->len;