There were two issues with the carp key configuration in the new netlink
code.
The first is that userspace failed to actually pass the CARP_NL_KEY
attribute to the kernel, so a key was never set.
The second issue is that snl_attr_get_string() returns a pointer to the
string inside the netlink message. It does not copy the string to the
target buffer. That's somewhat inconvenient to work with in libifconfig
where we have a static buffer for the key.
Introduce snl_attr_copy_string() which can copy a string to a target
buffer and uses the 'arg' parameter to pass the buffer size, so it
doesn't accidentally exceed the available space.
Reviewed by: melifaro
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D39874
Replacing rtsock with netlink also means providing similar tracing facilities,
rtsock provides `route -n monitor` interface, where each message can be traced
to the originating PID.
This diff closes the feature gap between rtsock and netlink in that regard.
Netlink works slightly differently from rtsock, as it is a generic message
"broker". It calls some kernel KPIs and returns the result to the caller.
Other Netlink consumers gets notified on the changed kernel state using the
relevant subsystem callbacks. Typically, it is close to impossible to pass
some data through these KPIs to enhance the notification.
This diff approaches the problem by using osd(9) to assign the relevant
socket pointer (`'nlp`) to the per-socket taskqueue execution thread.
This change allows to recover the pointer in the aforementioned notification
callbacks and extract some additional data.
Using `osd(9)` (and adding additional metadata) to the notification receiver
comes with some additional cost attached, so this interface needs to be
enabled explicitly by using a newly-created `NETLINK_MSG_INFO` `SOL_NETLINK`
socket option.
The actual medatadata (which includes the originator PID) is provided via
control messages. To enable extensibility, the control message data is
encoded in the standard netlink(TLV-based) fashion. The list of the
currently-provided properties can be found in `nlmsginfo_attrs`.
snl(3) is extended to enable decoding of netlink messages with metadata
(`snl_read_message_dbg()` stores the parsed structure in the provided buffer).
Differential Revision: https://reviews.freebsd.org/D39391
* Move LLT_ADDEDPROXY handling into lltable_link_entry() to
reduct duplication
* Use standard lltable_delete_addr() for entry deletion
* Add (forgotten) call to llt_post_resolved handler after
adding the entry via netlink.
MFC after: 2 weeks
This change adds netlink create/modify/dump interfaces to the `if_clone.c`.
The previous attempt with storing the logic inside `netlink/route/iface_drivers.c`
did not quite work, as, for example, dumping interface-specific state
(like vlan id or vlan parent) required some peeking into the private interfaces.
The new interfaces are added in a compatible way - callers don't have to do anything
unless they are extended with Netlink.
Reviewed by: kp
Differential Revision: https://reviews.freebsd.org/D39032
MFC after: 1 month
Current Netlink message writer code relies on executing callbacks
with arbitrary data (pointer or integer) to flush the completed
messages.
This arbitrary data is stored as a union of { void *, uint64_t }.
At some stage, the message flushing code copied this data, using
direct uint64_t assignment instead of copying the union. It lead
to failure on CHERI, as sizeof(pointer) == 16 there.
Fix the code by making union non-anonymous and copying it entirely.
Reviewed by: br, jhb, jrtc27
Differential Revision: https://reviews.freebsd.org/D39557
MFC after: 2 weeks
Use route destination sockaddr when the gateway is eiter AF_LINK or
has the different family (IPv4 over IPv6). This change ensures
the nexthop IFA has the same family as the destination.
Reported by: Dmitriy Smirnov <fox@sage.su>
Tested by: Dmitriy Smirnov <fox@sage.su>
MFC after: 3 days
Use already-existing RTM_F_PREFIX rtm_flag to indicate that the
request assumes exact-prefix lookup instead of the
longest-prefix-match.
MFC after: 2 weeks
Use full-featured ifa_ifwithroute() to guess route ifa/ifp
instead of ifa_ifwithnet(). This change makes the route addition
logic closer to the rt_getifa_fib() used by rtsock.
Reported by: glebius
Tested by: glebius
Differential Revision: https://reviews.freebsd.org/D39335
MFC after: 2 weeks
This change does the following:
Base Netlink KPIs (ability to register the family, parse and/or
write a Netlink message) are always present in the kernel. Specifically,
* Implementation of genetlink family/group registration/removal,
some base accessors (netlink_generic_kpi.c, 260 LoC) are compiled in
unconditionally.
* Basic TLV parser functions (netlink_message_parser.c, 507 LoC) are
compiled in unconditionally.
* Glue functions (netlink<>rtsock), malloc/core sysctl definitions
(netlink_glue.c, 259 LoC) are compiled in unconditionally.
* The rest of the KPI _functions_ are defined in the netlink_glue.c,
but their implementation calls a pointer to either the stub function
or the actual function, depending on whether the module is loaded or not.
This approach allows to have only 1k LoC out of ~3.7k LoC (current
sys/netlink implementation) in the kernel, which will not grow further.
It also allows for the generic netlink kernel customers to load
successfully without requiring Netlink module and operate correctly
once Netlink module is loaded.
Reviewed by: imp
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D39269
This change allow to open Netlink sockets in the non-vnet jails, even for
unpriviledged processes.
The security model largely follows the existing one. To be more specific:
* by default, every `NETLINK_ROUTE` command is **NOT** allowed in non-VNET
jail UNLESS `RTNL_F_ALLOW_NONVNET_JAIL` flag is specified in the command
handler.
* All notifications are **disabled** for non-vnet jails (requests to
subscribe for the notifications are ignored). This will change to be more
fine-grained model once the first netlink provider requiring this gets
committed.
* Listing interfaces (RTM_GETLINK) is **allowed** w/o limits (**including**
interfaces w/o any addresses attached to the jail). The value of this is
questionable, but it follows the existing approach.
* Listing ARP/NDP neighbours is **forbidden**. This is a **change** from the
current approach - currently we list static ARP/ND entries belonging to the
addresses attached to the jail.
* Listing interface addresses is **allowed**, but the addresses are filtered
to match only ones attached to the jail.
* Listing routes is **allowed**, but the routes are filtered to provide only
host routes matching the addresses attached to the jail.
* By default, every `NETLINK_GENERIC` command is **allowed** in non-VNET jail
(as sub-families may be unrelated to network at all).
It is the goal of the family author to implement the restriction if
necessary.
Differential Revision: https://reviews.freebsd.org/D39206
MFC after: 1 month
Allow users to configure the address to send carp messages to. This
allows carp to be used in unicast mode, which is useful in certain
virtual configurations (e.g. AWS, VMWare ESXi, ...)
Reviewed by: melifaro
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D38940
Summary:
* add snl_send_message() as a convenient send wrapper
* add signed integer parsers
* add snl_read_reply_code() to simplify operation result checks
* add snl_read_reply_multi() to simplify reading multipart messages
* add snl_create_genl_msg_request()
* add snl_get_genl_family() to simplify family name->id resolution
* add tests for some of the functionality
Reviewed by: kp
Differential Revision: https://reviews.freebsd.org/D39092
MFC after: 2 weeks
This change adds the "default" parsers of _all_ route/link attributes
exported by the kernel.
It removes the need to declare similar parsers in the userland applications,
simplifying their logic.
Differential Revision: https://reviews.freebsd.org/D38979
MFC after: 2 weeks
Some routing socket defines (`RTM_` and `RTA_` ones) clash with the ones
used by the the Netlink.
As some rtsock definitions like interface flags or route flags are used in
both netlink and rtsock, provide a convenient way to include those without
running into the define collision.
Differential Revision: https://reviews.freebsd.org/D38982
MFC after: 2 weeks
* Remove unused nlattr_add_nla() - that's a duplicate of nlattr_add_raw().
* Calculate alignment only once in nlmsg_reserve_data_raw()
MFC after: 2 weeks
