When the dname is found in the compression map and compress is true,
this copy is as it will simply be overwritten later. This could provide
a very slight speedup.
* properly set extended rcode when packing
When calling `SetExtendedRcode`, we expect to get the full extended
rcode, not the rcode after we shift 4 bytes right.
* fix extended rcode
* fix TestOPTTtl test
* set error messages in TestPackExtendedBadCookie
* Set Rcode with extended rcode
* |=
* Set extended RCODE field to 0 when RCODE is not an extended one.
+ unittests
* Force setting extended rcode if we have an OPT available.
* go fmt + @tmthrgd comments
* comments and nits
* reformat comment
* Simplify appendByte
* Add test case and benchmark for sprintName
* Add test case and benchmark for sprintTxtOctet
* Add test case and benchmark for sprintTxt
* Use strings.Builder for sprint* functions in types.go
* Use writeByte helper in unpackString
* Rename writeByte to writeEscapedByte
This better captures the purpose of this function.
These two functions were identical (sans-variable names) before I
optimized unpackString in 5debfeec63.
This will improve the performance of it's only caller unpackTxt and is
covered by the test and benchmark added in 5debfeec63.
* Remove redundant parenthesis
These were caught with:
gofmt -r '(a) -> a' -w *.go
This commit only includes the changes where the formatting makes the
ordering of operations clear.
* Remove more redundant parenthesis
These were caught with:
gofmt -r '(a) -> a' -w *.go
This commit includes the remaining changes where the formatting does not
make the ordering of operations as clear as the previous commit.
* Fixed len computation when size just goes beyond 14 bits
* Added bouds checks around 14bits
* Len() always right including when around 14bits boudaries
* Avoid splitting into labels when not applicable
* Fixed comments
* Added comments in code
* Added new test cases
* Fixed computation of Len() for SRV and all kind of records
* Fixed Sign that was relying on non-copy for Unit tests
* Removed unused padding
* Fixed typo in PackBuffer() function
* Added comment about packBufferWithCompressionMap() for testing purposes
* do not modify dns.Rcode when packing to wire format
When the message has an EDNS0 option in the additional section and
dns.Msg.Rcode is set to an extended rcode, dns.Msg.PackBuffer() modifies
dns.Msg.Rcode.
If you were to `Pack` the message and log it after, the Rcode would show
NOERROR.
Running the test before the change would error with:
```
=== RUN TestPackNoSideEffect
--- FAIL: TestPackNoSideEffect (0.00s)
msg_test.go:51: after pack: Rcode is expected to be BADVERS
```
after fixing dns.Msg.PackBuffer(), all tests are still passing.
Fixes#674
* address comments from PR#675
This offset max was not taking into account leading Len() to emit a
smaller value that could not be matched by Pack(), i.e all names can
be fully compressed or used as a target for compression.
Split length tests off in seperate file length_test.go to clean up
dns_test.og a bit.
We currently use information from a potential attacker to pre-allocate slices for the Question, Answer, etc. sections. This allows an attacker to force allocation of several MiB per parsed Msg.
Instead, don't pre-allocate those slices. append() always allocates in powers of two, which is probably the best we can do.
Fixes#609.
* 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 a094f77489)
* 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.
