TC uses all possible sub-message formats:
- nested attrs
- fixed headers + nested attrs
- fixed headers
- empty
Nested attrs are already supported for rt-link. Add support
for remaining 3. The empty and fixed headers ones are fairly
trivial, we can fake a Binary or Flags type instead of a Nest.
For fixed headers + nest we need to teach nest parsing and
nest put to handle fixed headers.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250520161916.413298-10-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reverse parsing lets YNL convert bad and missing attr pointers
from extack into a string like "missing attribute nest1.nest2.attr_name".
It's a feature that's unique to YNL C AFAIU (even the Python YNL
can't do nested reverse parsing). Add support for reverse-parsing
of sub-messages.
To simplify the logic and the code annotate the type policies
with extra metadata. Mark the selectors and the messages with
the information we need. We assume that key / selector always
precedes the sub-message while parsing (and also if there are
multiple sub-messages like in rt-link they are interleaved
selector 1 ... submsg 1 ... selector 2 .. submsg 2, not
selector 1 ... selector 2 ... submsg 1 ... submsg 2).
The rt-link sample in a subsequent changes shows reverse parsing
of sub-messages in action.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250515231650.1325372-8-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Adjust parsing and rendering appropriately to make sub-messages work.
Rendering is pretty trivial, as the submsg -> netlink conversion looks
like rendering a nest in which only one attr was set. Only trick
is that we use the enum value of the sub-message rather than the nest
as the type, and effectively skip one layer of nesting. A real double
nested struct would look like this:
[SELECTOR]
[SUBMSG]
[NEST]
[MSG1-ATTR]
A submsg "is" the nest so by skipping I mean:
[SELECTOR]
[SUBMSG]
[MSG1-ATTR]
There is no extra validation in YNL if caller has set the selector
matching the submsg type (e.g. link type = "macvlan" but the nest
attrs are set to carry "veth"). Let the kernel handle that.
Parsing side is a little more specialized as we need to render and
insert a new kind of function which switches between what to parse
based on the selector. But code isn't too complicated.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250515231650.1325372-7-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Strings from the kernel are guaranteed to be null terminated and
ynl_attr_validate() checks for this. But it doesn't check if the string
has a len of 0, which would cause problems when trying to access
data[len - 1]. Fix this by checking that len is positive.
Signed-off-by: David Wei <dw@davidwei.uk>
Link: https://patch.msgid.link/20250503043050.861238-1-dw@davidwei.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rtnetlink has variety of ops with different fixed headers.
Detect that op fixed header is not the same as family one,
and use sizeof() directly. For reverse parsing we need to
pass the fixed header len along the policy (in the socket
state).
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20250429154704.2613851-13-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add support for multi attr strings (needed for link alt_names).
We record the length individual strings in a len member, to do
the same for multi-attr create a struct ynl_string in ynl.h
and use it as a layer holding both the string and its length.
Since strings may be arbitrary length dynamically allocate each
individual one.
Adjust arg_member and struct member to avoid spacing the double
pointers to get "type **name;" rather than "type * *name;"
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20250429154704.2613851-8-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Classic netlink makes extensive use of flags. Support specifying
them the same way as attributes are specified (using a helper),
for example:
rt_link_newlink_req_set_nlflags(req, NLM_F_CREATE | NLM_F_ECHO);
Wrap the code up in a RenderInfo predicate. I think that some
genetlink families may want this, too. It should be easy to
add a spec property later.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20250429154704.2613851-5-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Make sure the codegen calls the right YNL lib helper to start
the request based on family type. Classic netlink request must
not include the genl header.
Conversely don't expect genl headers in the responses.
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250410014658.782120-10-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Classic netlink has static family IDs specified in YAML,
there is no family name -> ID lookup. Support providing
the ID info to the library via the generated struct and
make library use it. Since NETLINK_ROUTE is ID 0 we need
an extra boolean to indicate classic_id is to be used.
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250410014658.782120-8-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netlink reports which attribute was incorrect by sending back
an attribute offset. Offset points to the address of struct nlattr,
but to interpret the type we also need the nesting path.
Attribute IDs have different meaning in different nests
of the same message.
Correct the condition for "is the offset within current attribute".
ynl_attr_data_len() does not include the attribute header,
so the end offset was off by 4 bytes.
This means that we'd always skip over flags and empty nests.
The devmem tests, for example, issues an invalid request with
empty queue nests, resulting in the following error:
YNL failed: Kernel error: missing attribute: .queues.ifindex
The message is incorrect, "queues" nest does not have an "ifindex"
attribute defined. With this fix we decend correctly into the nest:
YNL failed: Kernel error: missing attribute: .queues.id
Fixes: 86878f14d7 ("tools: ynl: user space helpers")
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250124012130.1121227-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Move python code to a separate directory so it can be
packaged as a python module. Updates existing references
in selftests and docs.
Also rename ynl-gen-[c|rst] to ynl_gen_[c|rst], avoid
dashes as these prevent easy imports for entrypoints.
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/a4151bad0e6984e7164d395125ce87fd2e048bf1.1736343575.git.jstancek@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When parsing throws an exception one often has to figure out which
attribute couldn't be parsed from first principles. For families
with large message parsing trees like rtnetlink guessing the
attribute can be hard.
Print a bit of information as the exception travels out, e.g.:
# when dumping rt links
Error decoding 'flags' from 'linkinfo-ip6tnl-attrs'
Error decoding 'data' from 'linkinfo-attrs'
Error decoding 'linkinfo' from 'link-attrs'
Traceback (most recent call last):
File "/home/kicinski/linux/./tools/net/ynl/cli.py", line 119, in <module>
main()
File "/home/kicinski/linux/./tools/net/ynl/cli.py", line 100, in main
reply = ynl.dump(args.dump, attrs)
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 1064, in dump
return self._op(method, vals, dump=True)
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 1058, in _op
return self._ops(ops)[0]
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 1045, in _ops
rsp_msg = self._decode(decoded.raw_attrs, op.attr_set.name)
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 738, in _decode
subdict = self._decode(NlAttrs(attr.raw), attr_spec['nested-attributes'], search_attrs)
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 763, in _decode
decoded = self._decode_sub_msg(attr, attr_spec, search_attrs)
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 714, in _decode_sub_msg
subdict = self._decode(NlAttrs(attr.raw, offset), msg_format.attr_set)
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 749, in _decode
decoded = attr.as_scalar(attr_spec['type'], attr_spec.byte_order)
File "/home/kicinski/linux/tools/net/ynl/lib/ynl.py", line 147, in as_scalar
return format.unpack(self.raw)[0]
struct.error: unpack requires a buffer of 2 bytes
The Traceback is what we would previously see, the "Error..."
messages are new. We print a message per level (in the stack
order). Printing single combined message gets tricky quickly
given sub-messages etc.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250107022820.2087101-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the correct attribute space for sub-message key lookup in nested
attributes when adding attributes. This fixes rt_link where the "kind"
key and "data" sub-message are nested attributes in "linkinfo".
For example:
./tools/net/ynl/cli.py \
--create \
--spec Documentation/netlink/specs/rt_link.yaml \
--do newlink \
--json '{"link": 99,
"linkinfo": { "kind": "vlan", "data": {"id": 4 } }
}'
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Fixes: ab463c4342 ("tools/net/ynl: Add support for encoding sub-messages")
Link: https://patch.msgid.link/20241213130711.40267-1-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The notification handling in ynl is currently very simple, using sleep()
to wait a period of time and then handling all the buffered messages in
a single batch.
This patch adds async notification handling so that messages can be
processed as they are received. This makes it possible to use ynl as a
library that supplies notifications in a timely manner.
- Add poll_ntf() to be a generator that yields 1 notification at a
time and blocks until a notification is available.
- Add a --duration parameter to the CLI, with --sleep as an alias.
./tools/net/ynl/cli.py \
--spec <SPEC> --subscribe <TOPIC> [ --duration <SECS> ]
The cli will report any notifications for duration seconds and then
exit. If duration is not specified, then it will poll forever, until
interrupted.
Here is an example python snippet that shows how to use ynl as a library
for receiving notifications:
ynl = YnlFamily(f"{dir}/rt_route.yaml")
ynl.ntf_subscribe('rtnlgrp-ipv4-route')
for event in ynl.poll_ntf():
handle(event)
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20241113090843.72917-3-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit 1bf70e6c3a.
This modification to check_ntf() is being reverted so that its behaviour
remains equivalent to ynl_ntf_check() in the C YNL. Instead a new
poll_ntf() will be added in a separate patch.
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20241113090843.72917-2-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Package build environments like Fedora rpmbuild introduced hardening
options (e.g. -pie -Wl,-z,now) by passing a -spec option to CFLAGS
and LDFLAGS.
ynl Makefiles currently override CFLAGS but not LDFLAGS, which leads
to a mismatch and build failure:
CC sample devlink
/usr/bin/ld: devlink.o: relocation R_X86_64_32 against symbol `ynl_devlink_family' can not be used when making a PIE object; recompile with -fPIE
/usr/bin/ld: failed to set dynamic section sizes: bad value
collect2: error: ld returned 1 exit status
Extend CFLAGS to support hardening options set by build environment.
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/265b2d5d3a6d4721a161219f081058ed47dc846a.1731399562.git.jstancek@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sometimes the names of the enum entries are self-explanatory
or come from standards. Forcing authors to write trivial kdoc
for each of such entries seems unreasonable, but kdoc would
complain about undocumented entries.
Detect enums which only have documentation for the entire
type and no documentation for entries. Render their doc
as a plain comment.
Link: https://patch.msgid.link/20241103165314.1631237-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The notification handling in ynl is currently very simple, using sleep()
to wait a period of time and then handling all the buffered messages in
a single batch.
This patch changes the notification handling so that messages are
processed as they are received. This makes it possible to use ynl as a
library that supplies notifications in a timely manner.
- Change check_ntf() to be a generator that yields 1 notification at a
time and blocks until a notification is available.
- Use the --sleep parameter to set an alarm and exit when it fires.
This means that the CLI has the same interface, but notifications get
printed as they are received:
./tools/net/ynl/cli.py --spec <SPEC> --subscribe <TOPIC> [ --sleep <SECS> ]
Here is an example python snippet that shows how to use ynl as a library
for receiving notifications:
ynl = YnlFamily(f"{dir}/rt_route.yaml")
ynl.ntf_subscribe('rtnlgrp-ipv4-route')
for event in ynl.check_ntf():
handle(event)
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Tested-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20241018093228.25477-1-donald.hunter@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ncdevmem is a devmem TCP netcat. It works similarly to netcat, but it
sends and receives data using the devmem TCP APIs. It uses udmabuf as
the dmabuf provider. It is compatible with a regular netcat running on
a peer, or a ncdevmem running on a peer.
In addition to normal netcat support, ncdevmem has a validation mode,
where it sends a specific pattern and validates this pattern on the
receiver side to ensure data integrity.
Suggested-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20240910171458.219195-13-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Execution of command:
./tools/net/ynl/cli.py --spec Documentation/netlink/specs/dpll.yaml /
--subscribe "monitor" --sleep 10
fails with:
File "/repo/./tools/net/ynl/cli.py", line 109, in main
ynl.check_ntf()
File "/repo/tools/net/ynl/lib/ynl.py", line 924, in check_ntf
op = self.rsp_by_value[nl_msg.cmd()]
KeyError: 19
Parsing Generic Netlink notification messages performs lookup for op in
the message. The message was not yet decoded, and is not yet considered
GenlMsg, thus msg.cmd() returns Generic Netlink family id (19) instead of
proper notification command id (i.e.: DPLL_CMD_PIN_CHANGE_NTF=13).
Allow the op to be obtained within NetlinkProtocol.decode(..) itself if the
op was not passed to the decode function, thus allow parsing of Generic
Netlink notifications without causing the failure.
Suggested-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/netdev/m2le0n5xpn.fsf@gmail.com/
Fixes: 0a966d606c ("tools/net/ynl: Fix extack decoding for directional ops")
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20240904135034.316033-1-arkadiusz.kubalewski@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There are a couple of statements with two following semicolons,
replace these with just one semicolon.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20240802113436.448939-1-colin.i.king@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Support building the C YNL userspace library into one big static file.
We can then link selftests against it for easy to use C netlink
interface.
Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20240628003253.1694510-14-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use display hints for formatting scalar attrs. This is specifically
useful for formatting IPv4 addresses carried typically as u32.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20240626201234.2572964-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Dan, who's working on C++ YNL, pointed out that the C code
does not make policies const. Sprinkle some 'const's around.
Reported-by: Dan Melnic <dmm@meta.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Folks working on a C++ codegen would like to reuse the attribute
helpers directly. Add the few necessary casts, it's not too ugly.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/20240529192031.3785761-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
I often forget the exact naming of ops and have to look at
the spec to find it. Add support for listing the operations:
$ ./cli.py --spec .../netdev.yaml --list-ops
dev-get [ do, dump ]
page-pool-get [ do, dump ]
page-pool-stats-get [ do, dump ]
queue-get [ do, dump ]
napi-get [ do, dump ]
qstats-get [ dump ]
For completeness also support listing all ops (including
notifications:
# ./cli.py --spec .../netdev.yaml --list-msgs
dev-get [ dump, do ]
dev-add-ntf [ notify ]
dev-del-ntf [ notify ]
dev-change-ntf [ notify ]
page-pool-get [ dump, do ]
page-pool-add-ntf [ notify ]
page-pool-del-ntf [ notify ]
page-pool-change-ntf [ notify ]
page-pool-stats-get [ dump, do ]
queue-get [ dump, do ]
napi-get [ dump, do ]
qstats-get [ dump ]
Use double space after the name for slightly easier to read
output.
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240502164043.2130184-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When using YNL in tests appending the doc string to the type
name makes it harder to check that we got the correct error.
Put the doc under a separate key.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240426003111.359285-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
NLMSG_DONE contains an error code, it has to be extracted.
Prior to this change all dumps will end in success,
and in case of failure the result is silently truncated.
Fixes: e4b48ed460 ("tools: ynl: add a completely generic client")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240420020827.3288615-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add a "--multi <do-op> <json>" command line to ynl that makes it
possible to add several operations to a single netlink request payload.
The --multi command line option is repeated for each operation.
This is used by the nftables family for transaction batches. For
example:
./tools/net/ynl/cli.py \
--spec Documentation/netlink/specs/nftables.yaml \
--multi batch-begin '{"res-id": 10}' \
--multi newtable '{"name": "test", "nfgen-family": 1}' \
--multi newchain '{"name": "chain", "table": "test", "nfgen-family": 1}' \
--multi batch-end '{"res-id": 10}'
[None, None, None, None]
It can also be used for bundling get requests:
./tools/net/ynl/cli.py \
--spec Documentation/netlink/specs/nftables.yaml \
--multi gettable '{"name": "test", "nfgen-family": 1}' \
--multi getchain '{"name": "chain", "table": "test", "nfgen-family": 1}' \
--output-json
[{"name": "test", "use": 1, "handle": 1, "flags": [],
"nfgen-family": 1, "version": 0, "res-id": 2},
{"table": "test", "name": "chain", "handle": 1, "use": 0,
"nfgen-family": 1, "version": 0, "res-id": 2}]
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240418104737.77914-4-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
NetlinkProtocol.decode() was looking up ops by response value which breaks
when it is used for extack decoding of directional ops. Instead, pass
the op to decode().
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240418104737.77914-3-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
YNL currently reports None for empty dump:
$ cli.py ...netdev.yaml --dump page-pool-get
None
This doesn't matter for the CLI but when writing YNL based tests
having to deal with either list or None is annoying. Limit the
None conversion to non-dump ops:
$ cli.py ...netdev.yaml --dump page-pool-get
[]
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240412141436.828666-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add binary and integer sub-type support for indexed-array to display bond
arp and ns targets. Here is what the result looks like:
# ip link add bond0 type bond mode 1 \
arp_ip_target 192.168.1.1,192.168.1.2 ns_ip6_target 2001::1,2001::2
# ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/rt_link.yaml \
--do getlink --json '{"ifname": "bond0"}' --output-json | jq '.linkinfo'
"arp-ip-target": [
"192.168.1.1",
"192.168.1.2"
],
[...]
"ns-ip6-target": [
"2001::1",
"2001::2"
],
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20240404063114.1221532-3-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Typing e.nl_msg.error when processing exception is a bit tedious
and counter-intuitive. Set a local .error member to the positive
value of the netlink level error.
Reviewed-by: Petr Machata <petrm@nvidia.com>
Link: https://lore.kernel.org/r/20240403023426.1762996-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Checking if dump is empty requires a couple of casts.
Add a convenient wrapper.
Add an example use in the netdev sample, loopback is always
present so an empty dump is an error.
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://lore.kernel.org/r/20240329181651.319326-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The NLMSGERR_ATTR_POLICY extack attribute has been ignored by ynl up to
now. Extend extack decoding to include _POLICY and the nested
NL_POLICY_TYPE_ATTR_* attributes.
For example:
./tools/net/ynl/cli.py \
--spec Documentation/netlink/specs/rt_link.yaml \
--create --do newlink --json '{
"ifname": "12345678901234567890",
"linkinfo": {"kind": "bridge"}
}'
Netlink error: Numerical result out of range
nl_len = 104 (88) nl_flags = 0x300 nl_type = 2
error: -34 extack: {'msg': 'Attribute failed policy validation',
'policy': {'max-length': 15, 'type': 'string'}, 'bad-attr': '.ifname'}
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240328155636.64688-1-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some times it would be convenient to read the integer as hex, like
mask values.
Suggested-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20240327123130.1322921-2-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The family struct is auto-generated for new families, support
use of the sock_priv_* mechanism added in commit a731132424
("genetlink: introduce per-sock family private storage").
For example if the family wants to use struct sk_buff as its
private struct (unrealistic but just for illustration), it would
add to its spec:
kernel-family:
headers: [ "linux/skbuff.h" ]
sock-priv: struct sk_buff
ynl-gen-c will declare the appropriate priv size and hook
in function prototypes to be implemented by the family.
Link: https://lore.kernel.org/r/20240308190319.2523704-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The nlctrl genetlink-legacy family uses nest-type-value encoding as
described in Documentation/userspace-api/netlink/genetlink-legacy.rst
Add nest-type-value decoding to ynl.
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240306231046.97158-5-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ynl does not handle NlError exceptions so they get reported like program
failures. Handle the NlError exceptions and report the netlink errors
more cleanly.
Example now:
Netlink error: No such file or directory
nl_len = 44 (28) nl_flags = 0x300 nl_type = 2
error: -2 extack: {'bad-attr': '.op'}
Example before:
Traceback (most recent call last):
File "/home/donaldh/net-next/./tools/net/ynl/cli.py", line 81, in <module>
main()
File "/home/donaldh/net-next/./tools/net/ynl/cli.py", line 69, in main
reply = ynl.dump(args.dump, attrs)
^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/donaldh/net-next/tools/net/ynl/lib/ynl.py", line 906, in dump
return self._op(method, vals, [], dump=True)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/donaldh/net-next/tools/net/ynl/lib/ynl.py", line 872, in _op
raise NlError(nl_msg)
lib.ynl.NlError: Netlink error: No such file or directory
nl_len = 44 (28) nl_flags = 0x300 nl_type = 2
error: -2 extack: {'bad-attr': '.op'}
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240306231046.97158-3-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Extack decoding was using a hard-coded msg header size of 20 but
netlink-raw has a header size of 16.
Use a protocol specific msghdr_size() when decoding the attr offssets.
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240306231046.97158-2-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Donald points out that we don't check for overflows.
Stash the length of the message on nlmsg_pid (nlmsg_seq would
do as well). This allows the attribute helpers to remain
self-contained (no extra arguments). Also let the put
helpers continue to return nothing. The error is checked
only in (newly introduced) ynl_msg_end().
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20240305185000.964773-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For manual debug, allow printing the netlink level messages
to stderr.
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the size of the buffer we use for recv() configurable.
The details of the buffer sizing in netlink are somewhat
arcane, we could spend a lot of time polishing this API.
Let's just leave some hopefully helpful comments for now.
This is a for-developers-only feature, anyway.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
