static bool enable_name_policy(...) in ./src/udev/net/link-config.c
calls proc_cmdline(...) to get "line" initialized, but
proc_cmdline(...) does not guarantee that atleast when both
conditions (detect_container(NULL) > 0) and
read_full_file(...) returned < 0.
This essentially swaps the roles of rtnl and udev in networkd. After this
change libudev is only used for waiting for udev to initialize devices and
to get udev-specific information needed for some [Match] attributes.
This in particular simplifies the code in containers where udev is not really
useful, but also simplifies things and reduces round-trips in the non-container
case.
This does not belong in shared as it is mostly a detail of our networking subsystem.
Moreover, now we can use libudev here, which will simplify things.
Increase the chance of using the same link local address between reboots. The
pseudo random sequence of addresses we attempt is now seeded with data that is
very likely to stay the same between reboots, but at the same time be unique
to the specific machine/nic.
First we try to use the ID_NET_NAME_* data from the udev db combined with the
machin-id, which is guaranteed to be unique and persistent, if available. If
that is not possible (e.g., in containers where we don't have access to the
udev db) we fallback to using the MAC address of the interface, which is
guaranteed to be unique, and likely to be persistent.
[tomegun: three minor changes:
- don't expose HASH_KEY in the siphash24 header
- get rid of some compile-warnings (and some casts at the same time),
by using uint8_t[8] rather than uint64_t in the api
- added commit message]
safe_close() automatically becomes a NOP when a negative fd is passed,
and returns -1 unconditionally. This makes it easy to write lines like
this:
fd = safe_close(fd);
Which will close an fd if it is open, and reset the fd variable
correctly.
By making use of this new scheme we can drop a > 200 lines of code that
was required to test for non-negative fds or to reset the closed fd
variable afterwards.
Bring some arrays that are used for DEFINE_STRING_TABLE_LOOKUP() in the
same order than the enums they reference.
Also, pass the corresponding _MAX value to the array initalizer where
appropriate.
This also changes the names to MTUBytes and BitsPerSecond, respectively. Notice
that the speed was mistakenly documented to be in bytes before this change.
Previously the returned object of constructor functions where sometimes
returned as last, sometimes as first and sometimes as second parameter.
Let's clean this up a bit. Here are the new rules:
1. The object the new object is derived from is put first, if there is any
2. The object we are creating will be returned in the next arguments
3. This is followed by any additional arguments
Rationale:
For functions that operate on an object we always put that object first.
Constructors should probably not be too different in this regard. Also,
if the additional parameters might want to use varargs which suggests to
put them last.
Note that this new scheme only applies to constructor functions, not to
all other functions. We do give a lot of freedom for those.
Note that this commit only changes the order of the new functions we
added, for old ones we accept the wrong order and leave it like that.
- Add space between if/for and the opening parentheses
- Place the opening brace on same line as the function (not for udev)
From the CODING_STYLE
Try to use this:
void foo() {
}
instead of this:
void foo()
{
}
Use Description only internally, and allow Alias to be set
as a separate option. For instance SNMP uses ifalias for
a specific purpose, so let's not write to it by default.
Instead of individually checking for containers in each user do this
once in a new call proc_cmdline() that read the file only if we are not
in a container.
We set it to 10 secs (as we are only communicating with the kernel,
it seems we should be able to bail out sooner than sd-bus, which
uses 25).
When passing timout 0, the default is used, use this in link-config.
This introduces a new key MACAddressPolicy.
The possible policies are 'persistent' and 'random'.
'persistent' will do nothing if the current address is the hardware address,
but if the hardware does not have an address (or another address is set for
whatever reason), we will generate an address which will be random, but
persistent between boots (based on machineid and persistent netif name).
'random' will do nothing if the kernel already set a random address, otherwise
it will generate a random one and use that instead.
This patch sets MACAddressPolicy=persistent in the default .link file.
This introduces a new key NamePolicy, which takes an ordered list of naming
policies. The first successful one is applide. If all fail the value of Name
(if any) is used.
The possible policies are 'onboard', 'slot', 'path' and 'mac'.
This patch introduces a default link file, which replaces the equivalent udev
rule.
