linux/include
Johannes Berg d07dcf9aad netlink: add infrastructure to expose policies to userspace
Add, and use in generic netlink, helpers to dump out a netlink
policy to userspace, including all the range validation data,
nested policies etc.

This lets userspace discover what the kernel understands.

For families/commands other than generic netlink, the helpers
need to be used directly in an appropriate command, or we can
add some infrastructure (a new netlink family) that those can
register their policies with for introspection. I'm not that
familiar with non-generic netlink, so that's left out for now.

The data exposed to userspace also includes min and max length
for binary/string data, I've done that instead of letting the
userspace tools figure out whether min/max is intended based
on the type so that we can extend this later in the kernel, we
might want to just use the range data for example.

Because of this, I opted to not directly expose the NLA_*
values, even if some of them are already exposed via BPF, as
with min/max length we don't need to have different types here
for NLA_BINARY/NLA_MIN_LEN/NLA_EXACT_LEN, we just make them
all NL_ATTR_TYPE_BINARY with min/max length optionally set.

Similarly, we don't really need NLA_MSECS, and perhaps can
remove it in the future - but not if we encode it into the
userspace API now. It gets mapped to NL_ATTR_TYPE_U64 here.

Note that the exposing here corresponds to the strict policy
interpretation, and NLA_UNSPEC items are omitted entirely.
To get those, change them to NLA_MIN_LEN which behaves in
exactly the same way, but is exposed.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30 17:51:42 -07:00
..
acpi Additional ACPI updates for 5.7-rc1 2020-04-06 10:35:06 -07:00
asm-generic arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h> 2020-04-23 10:50:26 +09:00
clocksource
crypto crypto: curve25519 - do not pollute dispatcher based on assembler 2020-04-09 00:01:59 +09:00
drm drm/bridge: analogix_dp: Split bind() into probe() and real bind() 2020-04-09 10:29:35 +02:00
dt-bindings RISC-V Patches for the 5.7 Merge Window, Part 1 2020-04-09 10:51:30 -07:00
keys
kunit
kvm
linux tcp: add tp->dup_ack_counter 2020-04-30 13:24:01 -07:00
math-emu
media
misc
net netlink: add infrastructure to expose policies to userspace 2020-04-30 17:51:42 -07:00
pcmcia
ras
rdma
scsi SCSI misc on 20200402 2020-04-02 17:03:53 -07:00
soc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-04-25 20:18:53 -07:00
sound ASoC: Fixes for v5.7 2020-04-21 21:41:36 +02:00
target
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-04-25 20:18:53 -07:00
uapi netlink: add infrastructure to expose policies to userspace 2020-04-30 17:51:42 -07:00
vdso vdso/datapage: Use correct clock mode name in comment 2020-04-20 19:19:52 +02:00
video
xen xen: Use evtchn_type_t as a type for event channels 2020-04-07 12:12:54 +02:00