When user calls request_attrA_set() multiple times (for the same
attribute), and attrA is of type which allocates memory -
we try to free the previously associated values. For array
types (including multi-attr) we have only freed the array,
but the array may have contained pointers.
Refactor the code generation for free attr and reuse the generated
lines in setters to flush out the previous state. Since setters
are static inlines in the header we need to add forward declarations
for the free helpers of pure nested structs. Track which types get
used by arrays and include the right forwad declarations.
At least ethtool string set and bit set would not be freed without
this. Tho, admittedly, overriding already set attribute twice is likely
a very very rare thing to do.
Fixes: be5bea1cc0 ("net: add basic C code generators for Netlink")
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20250414211851.602096-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
YNL C can now generate code for simple classic netlink families.
Include rt-route in the Makefile for generation and add a sample.
$ ./tools/net/ynl/samples/rt-route
oif: wlp0s20f3 gateway: 192.168.1.1
oif: wlp0s20f3 dst: 192.168.1.0/24
oif: vpn0 dst: fe80::/64
oif: wlp0s20f3 dst: fe80::/64
oif: wlp0s20f3 gateway: fe80::200:5eff:fe00:201
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250410014658.782120-14-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If the type for the response to do and dump are the same we don't
generate it twice. This is called "type_consistent" in the generator.
Consider operations which only have dump to also be consistent.
This removes unnecessary "_dump" from the names. There's a number
of GET ops in classic Netlink which only have dump handlers.
Make sure we output the "onesided" types, normally if the type
is consistent we only output it when we render the do structures.
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20250410014658.782120-11-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
C codegen skips generating the structs if request/reply has no attrs.
In such cases the request op takes no argument and return int
(rather than response struct). In case of classic netlink a lot of
information gets passed using the fixed struct, however, so adjust
the logic to consider a request empty only if it has no attrs _and_
no fixed struct.
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20250410014658.782120-9-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>
The Makefile.deps lists uAPI headers to make the build work when
system headers are older than in-tree headers. The problem doesn't
occur for new headers, because system headers are not there at all.
But out-of-tree YNL clone on GH also uses this header to identify
header dependencies, and one day the system headers will exist,
and will get out of date. So let's add the headers we missed.
I don't think this is a fix, but FWIW the commits which added
the missing headers are:
commit 04e65df94b ("netlink: spec: add shaper YAML spec")
commit 49922401c2 ("ethtool: separate definitions that are gonna be generated")
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250205173352.446704-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A definition with a "header" property is an "external" definition
for C code, as in it is defined already in another C header file.
Other languages will need the exact value but C codegen should
not recreate it. So don't output those definitions in the uAPI
header.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20250203215510.1288728-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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>
Add a --family option to ynl to specify the spec by family name instead
of file path, with support for searching in-tree and system install
location and a --list-families option to show the available families.
./tools/net/ynl/pyynl/cli.py --family rt_addr --dump getaddr
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://patch.msgid.link/20250111154803.7496-1-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Empty nests are the same size as a flag at the netlink level
(just a 4 byte nlattr without a payload). They are sometimes
useful in case we want to only communicate a presence of
something but may want to add more details later.
This may be the case in the upcoming io_uring ZC patches,
for example.
Improve handling of nested empty structs. We already support
empty structs since a lot of netlink replies are empty, but
for nested ones we need minor tweaks to avoid pointless empty
lines and unused variables.
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Link: https://patch.msgid.link/20250108200758.2693155-1-kuba@kernel.org
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>
Essentially reverse the order of headers for userspace generated files.
Before (make -C tools/net/ynl/; cat tools/net/ynl/ethtool-user.h):
#include <linux/ethtool_netlink_generated.h>
#include <linux/ethtool.h>
#include <linux/ethtool.h>
#include <linux/ethtool.h>
After:
#include <linux/ethtool.h>
#include <linux/ethtool_netlink_generated.h>
While at it, make sure we track which headers we've already included
and include the headers only once.
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20241204155549.641348-6-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
