* limiting domain names to 255/63 octets/labels (#463)
(cherry picked from commit 0b729df06c)
* account for \ and \xxx in presentation format
(cherry picked from commit a094f774892fb4305051d185c2488cb43200c4d9)
* go fmt
* Add tests for UnpackDomainName
Domain names must not exceed 255 octets in wire format.
Ref gh-463
Ref gh-469
* Fix UnpackDomainName
* Introduce a long-domain sentinel error
A typed error would be better, but inconsistent with this library.
cf. https://dave.cheney.net/2016/04/27/dont-just-check-errors-handle-them-gracefully
* Generate the compressionHelper functions and fix compression.
This was a long standing TODO: generate the compression helper
functions. This now automatically picks up new names that can be
used for compression.
When packing add names to compression map:
When packing a message we should only compress when compress is true.
But whenever the compression map is not nil we should still add names
to it that can be *used* for future compression. The packing
inadvertently only added those names when compress would be true.
* Removed unused functions
* Work around golang/go#11833 predictable random issue.
In certain circumstances crypto/rand.Reader will return non-random
bytes. The most likely case is near boot, and as init is run when
the go program is started, it's possible that a non-random seed
could be used. While this is very unlikely to ever be an issue,
it is a very easy fix and it is preferable to be resilient.
Instead of seeding the global math/rand rng during init, a separate
math/rand.Rand is seeded upon the first call to Id. This also avoids
polluting the global math/rand rng which might be seeded elsewhere.
If crypto/rand.Reader fails, math/rand.Int63 will be called to
provide a seed. This is better than the current fallback to a seed
of 1.
This change introduces no noticeable performance overhead as the
global math/rand rng already uses a sync.Mutex internally.
* Document lack of performance overhead from mutex in `func id()`
* Test for proper parsing of whitespace-separated (TXT) character-strings
* Properly parse whitespace-separated (TXT) character-strings
* Remove non-RFC treatment of backslash sequences in character-strings
Fixes gh-420
* For tests, remove non-RFC treatment of backslashes in domain names
* Cleanup and removals
Gut rawmsg.go as most functions are not used. Reword some documentation.
Add more types to be checked for name compression.
* Yeah, we do use these
* Remove this function as well - only used one
Update the size-xxx-member tags to point to another field in the struct
that should be used for the length in that field. Fix NSEC3/HIP and TSIG
to use to this and generate the correct pack/unpack functions for them.
Remove IPSECKEY from the lib and handle it as an unknown record - it is
such a horrible RR, needed kludges before - now just handle it as an
unknown RR.
All types now use generated pack and unpack functions. The blacklist is
removed.
Make the reflection types a black list (these types use (or should use)
the tag 'size-xxx' in their struct definition.s
HIP, IPSECKEY, NSEC3, TSIG
All other types don't use reflection anymore.
* Return a pointer to the header when there is no rdata, this restores old
behavior. The rest of the conversion mostly hangs on getting size-hex
right, but then packStruct and packStructValue and the unpack variant
can be killed.
* Generate pack and unpack for all embedded types as well.
* Fix PrivateRRs, register an unpack function as well, when you register
a new PrivateRR.
* Add the tag octet, nsec, []domains and more to msg_helper.go
* Make the error variable always named err.
Sometimes the error variable was named 'err' sometimes 'e'. Sometimes
'e' refered to an EDNS or string and not an error type.
* Use t.Errorf instead of t.Logf & t.Fail.
* Remove {un,}packUint{16,32}Msg functions.
unpackUint16Msg unpackUint32Msg packUint16Msg packUint32Msg implemented
functionality that is part of the encoding/binary package.
* Use encoding/binary's encoding in more places.
Add dns:txt parsing helper to prevent compile errors. This allows
us to generate all unpack/pack function.
Add pack to the RR interface definition and add this method to
PrivateRR.
We still use typeToUnpack to select which types don't use reflection.
* Use crypto/rand to seed math/rand instead of using the default seed
* Better seeding+generation and fallback on crypto/rand.Read failure
* Remove user warning
Remove the use of reflection when packing and unpacking, instead
generate all the pack and unpack functions using msg_generate.
This will generate zmsg.go which in turn calls the helper functions from
msg_helper.go.
This increases the speed by about ~30% while cutting back on memory
usage. Not all RRs are using it, but that will be rectified in upcoming
PR.
Most of the speed increase is in the header/question section parsing.
These functions *are* not generated, but straight forward enough. The
implementation can be found in msg.go.
The new code has been fuzzed by go-fuzz, which turned up some issues.
All files that started with 'z', and not autogenerated were renamed,
i.e. zscan.go is now scan.go.
Reflection is still used, in subsequent PRs it will be removed entirely.
This process probably fixes a bug in NSAPPTR.len(), after a similar one was
found in HINFO.len().
This should also make it easier to make changes to these functions, and
check their correctness.
Generate the code by running "go generate".
Add function that dedups a list of RRs. Work on strings, which
adds garbage, but seems to be the least intrusive and takes the
last amount of memory.
Some fmt changes snook in as well.
When a pointer points to a empty name, the "return '.'" special case used to
kick in which is not pointer-aware so it would reset the parsing offset to
the pointer target
This was independently found and fixed in c13d4ee, I'm submitting this patch
anyway as it seems a bit more robust and DRY [citation needed].
If the root label is compressed (which is 2 bytes, the root label
itself is only 1 byte, so why do it?), go dns incorrectly set the
offset when encountering such a name.
Fixes#234
A handful of EDNS options have been standardized, and they each have a type defined in GoDNS. However there is currently no way a development team can use GoDNS with internally defined options, or with new options that may be proposed in the future.
This change solves the problem by giving users an EDNS0_CUSTOM type to allow clients to send, and servers to receive, custom EDNS options.
Danny Berger
Richard Gibson
Miek Gieben
Olafur Gudmundsson
Tom Thorogood
Matthijs Mekking
Preet Bhinder
Michael Haro
Roland Bracewell Shoemaker
Shumon Huque
Nick Galbreath
James Hartig
Filippo Valsorda
Harvo Jones