[GENL]: Provide more information to userspace about registered genl families
Additionaly exports the following information when providing
the list of registered generic netlink families:
- protocol version
- header size
- maximum number of attributes
- list of available operations including
- id
- flags
- avaiability of policy and doit/dumpit function
libnl HEAD provides a utility to read this new information:
0x0010 nlctrl version 1
hdrsize 0 maxattr 6
op GETFAMILY (0x03) [POLICY,DOIT,DUMPIT]
0x0011 NLBL_MGMT version 1
hdrsize 0 maxattr 0
op unknown (0x02) [DOIT]
op unknown (0x03) [DOIT]
....
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/genetlink.h b/include/linux/genetlink.h
index 84f12a4..9049dc6 100644
--- a/include/linux/genetlink.h
+++ b/include/linux/genetlink.h
@@ -16,6 +16,8 @@
#define GENL_HDRLEN NLMSG_ALIGN(sizeof(struct genlmsghdr))
+#define GENL_ADMIN_PERM 0x01
+
/*
* List of reserved static generic netlink identifiers:
*/
@@ -43,9 +45,25 @@
CTRL_ATTR_UNSPEC,
CTRL_ATTR_FAMILY_ID,
CTRL_ATTR_FAMILY_NAME,
+ CTRL_ATTR_VERSION,
+ CTRL_ATTR_HDRSIZE,
+ CTRL_ATTR_MAXATTR,
+ CTRL_ATTR_OPS,
__CTRL_ATTR_MAX,
};
#define CTRL_ATTR_MAX (__CTRL_ATTR_MAX - 1)
+enum {
+ CTRL_ATTR_OP_UNSPEC,
+ CTRL_ATTR_OP_ID,
+ CTRL_ATTR_OP_FLAGS,
+ CTRL_ATTR_OP_POLICY,
+ CTRL_ATTR_OP_DOIT,
+ CTRL_ATTR_OP_DUMPIT,
+ __CTRL_ATTR_OP_MAX,
+};
+
+#define CTRL_ATTR_OP_MAX (__CTRL_ATTR_OP_MAX - 1)
+
#endif /* __LINUX_GENERIC_NETLINK_H */
diff --git a/include/net/genetlink.h b/include/net/genetlink.h
index 97d6d3a..4a38d85 100644
--- a/include/net/genetlink.h
+++ b/include/net/genetlink.h
@@ -27,8 +27,6 @@
struct list_head family_list; /* private */
};
-#define GENL_ADMIN_PERM 0x01
-
/**
* struct genl_info - receiving information
* @snd_seq: sending sequence number
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 3ac942c..49bc2db 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -387,7 +387,10 @@
static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq,
u32 flags, struct sk_buff *skb, u8 cmd)
{
+ struct nlattr *nla_ops;
+ struct genl_ops *ops;
void *hdr;
+ int idx = 1;
hdr = genlmsg_put(skb, pid, seq, GENL_ID_CTRL, 0, flags, cmd,
family->version);
@@ -396,6 +399,37 @@
NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name);
NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id);
+ NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version);
+ NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize);
+ NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr);
+
+ nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS);
+ if (nla_ops == NULL)
+ goto nla_put_failure;
+
+ list_for_each_entry(ops, &family->ops_list, ops_list) {
+ struct nlattr *nest;
+
+ nest = nla_nest_start(skb, idx++);
+ if (nest == NULL)
+ goto nla_put_failure;
+
+ NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd);
+ NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags);
+
+ if (ops->policy)
+ NLA_PUT_FLAG(skb, CTRL_ATTR_OP_POLICY);
+
+ if (ops->doit)
+ NLA_PUT_FLAG(skb, CTRL_ATTR_OP_DOIT);
+
+ if (ops->dumpit)
+ NLA_PUT_FLAG(skb, CTRL_ATTR_OP_DUMPIT);
+
+ nla_nest_end(skb, nest);
+ }
+
+ nla_nest_end(skb, nla_ops);
return genlmsg_end(skb, hdr);
@@ -411,6 +445,9 @@
int chains_to_skip = cb->args[0];
int fams_to_skip = cb->args[1];
+ if (chains_to_skip != 0)
+ genl_lock();
+
for (i = 0; i < GENL_FAM_TAB_SIZE; i++) {
if (i < chains_to_skip)
continue;
@@ -428,6 +465,9 @@
}
errout:
+ if (chains_to_skip != 0)
+ genl_unlock();
+
cb->args[0] = i;
cb->args[1] = n;