Commit Graph

486 Commits

Author SHA1 Message Date
Tom Thorogood 0d29b283ac
Optimise sprintX functions in types.go (#757)
* 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.
2018-10-06 02:06:59 +09:30
Tom Thorogood 7ca2be95a9 NSEC type bitmap packing bug (#768)
* Add test case for NSEC after packing and unpacking

This is ported from:
https://gist.github.com/cesarkuroiwa/ebc2b4fb1103a7e88824865184f0c73c

* Clear msg data after pointer in packDomainName
2018-10-04 07:39:45 +01:00
Tom Thorogood 7f61c6631b
Fix dominikh/go-tools nits (#758)
* Remove unused functions and consts

* Address gosimple nits

* Address staticcheck nits

This excludes several that were intentional or weren't actual errors.

* Reduce size of lex struct

This reduces the size of the lex struct by 8 bytes from:
  lex.token string: 0-16 (size 16, align 8)
  lex.tokenUpper string: 16-32 (size 16, align 8)
  lex.length int: 32-40 (size 8, align 8)
  lex.err bool: 40-41 (size 1, align 1)
  lex.value uint8: 41-42 (size 1, align 1)
  padding: 42-48 (size 6, align 0)
  lex.line int: 48-56 (size 8, align 8)
  lex.column int: 56-64 (size 8, align 8)
  lex.torc uint16: 64-66 (size 2, align 2)
  padding: 66-72 (size 6, align 0)
  lex.comment string: 72-88 (size 16, align 8)
to:
  lex.token string: 0-16 (size 16, align 8)
  lex.tokenUpper string: 16-32 (size 16, align 8)
  lex.length int: 32-40 (size 8, align 8)
  lex.err bool: 40-41 (size 1, align 1)
  lex.value uint8: 41-42 (size 1, align 1)
  lex.torc uint16: 42-44 (size 2, align 2)
  padding: 44-48 (size 4, align 0)
  lex.line int: 48-56 (size 8, align 8)
  lex.column int: 56-64 (size 8, align 8)
  lex.comment string: 64-80 (size 16, align 8)

* Reduce size of response struct

This reduces the size of the response struct by 8 bytes from:
  response.msg []byte: 0-24 (size 24, align 8)
  response.hijacked bool: 24-25 (size 1, align 1)
  padding: 25-32 (size 7, align 0)
  response.tsigStatus error: 32-48 (size 16, align 8)
  response.tsigTimersOnly bool: 48-49 (size 1, align 1)
  padding: 49-56 (size 7, align 0)
  response.tsigRequestMAC string: 56-72 (size 16, align 8)
  response.tsigSecret map[string]string: 72-80 (size 8, align 8)
  response.udp *net.UDPConn: 80-88 (size 8, align 8)
  response.tcp net.Conn: 88-104 (size 16, align 8)
  response.udpSession *github.com/tmthrgd/dns.SessionUDP: 104-112 (size 8, align 8)
  response.writer github.com/tmthrgd/dns.Writer: 112-128 (size 16, align 8)
  response.wg *sync.WaitGroup: 128-136 (size 8, align 8)
to:
  response.msg []byte: 0-24 (size 24, align 8)
  response.hijacked bool: 24-25 (size 1, align 1)
  response.tsigTimersOnly bool: 25-26 (size 1, align 1)
  padding: 26-32 (size 6, align 0)
  response.tsigStatus error: 32-48 (size 16, align 8)
  response.tsigRequestMAC string: 48-64 (size 16, align 8)
  response.tsigSecret map[string]string: 64-72 (size 8, align 8)
  response.udp *net.UDPConn: 72-80 (size 8, align 8)
  response.tcp net.Conn: 80-96 (size 16, align 8)
  response.udpSession *github.com/tmthrgd/dns.SessionUDP: 96-104 (size 8, align 8)
  response.writer github.com/tmthrgd/dns.Writer: 104-120 (size 16, align 8)
  response.wg *sync.WaitGroup: 120-128 (size 8, align 8)
2018-09-27 04:02:05 +09:30
Tom Thorogood f195b71879 Replace unpackTxtString with identical unpackString (#751)
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.
2018-09-26 09:14:19 +01:00
Tom Thorogood c9b812d1d9 Remove redundant parenthesis (#727)
* 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.
2018-08-16 17:05:27 +01:00
Miek Gieben 3745b9737d
Small comment tweaks (#678)
Some post #668 comments nits.
2018-05-16 08:53:51 +01:00
Pierre Souchay 09649115c1 Fixed len computation when size just goes beyond 14 bits (#668)
* 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
2018-05-16 07:20:13 +01:00
chantra 1f2aa4c780 do not modify dns.Rcode when packing to wire format (#675)
* 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
2018-05-13 08:36:02 +01:00
Miek Gieben dfb943b13e
Take the max compression offset into account in Len(). (#658)
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.
2018-04-01 09:45:32 +01:00
chantra 5b169d1842 [msg] Add UnpackRRWithHeader (#643)
This function allow to extra the raw content of a record type based on
an existing header.
Fixes #633
2018-03-15 09:09:45 +00:00
Lorenz Bauer 9088876525 Don't use untrusted lengths from Header to pre-allocate (#610)
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.
2017-12-21 10:24:07 +00:00
Miek Gieben 5f2d7c7013
Unpack: return header (#608)
When we unpack a message and only have the header consider it a valid
message and don't return an error.
2017-12-20 10:51:13 +00:00
Miek Gieben b38dc3dcb7
Cleanup: gofmt -w -s *.go (#548)
Some renames of internal names to make go lint happier.
2017-11-03 16:15:35 +00:00
Tom Thorogood 5f64fb22f9 Simplify compressed length code (#527)
* Add BenchmarkMsgLengthNoCompression

* Simplify compressedLen loops

* Fix typo in compressionLenSlice
2017-10-13 17:21:12 +02:00
Danny Berger 113c7538ea Fix minor typos in comments (#486) 2017-04-26 18:46:52 +01:00
Richard Gibson c1bdeb82b2 Domain name limits (#478)
* 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
2017-03-29 20:43:02 +01:00
Miek Gieben 25ac7f1714 Revert "limiting domain names to 255/63 octets/labels (#463)"
This reverts commit 0b729df06c.
2017-03-21 07:03:31 +00:00
Olafur Gudmundsson 0b729df06c limiting domain names to 255/63 octets/labels (#463) 2017-02-21 22:36:40 +00:00
Miek Gieben 75229eecb7 msg.go: don't fiddle with Compress (#460)
Don't set Compress to false on dns to calucate the uncompressed length,
instead a a function where the compression is a flag and use that.
2017-02-17 12:10:30 +00:00
Miek Gieben 74ec3b2433 Generate the compressionHelper functions (#454)
* 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
2017-02-17 09:48:37 +00:00
Tom Thorogood f3c59acd3d Work around golang/go#11833 predictable random issue in Id. (#447)
* 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()`
2017-02-05 08:47:07 +00:00
Matthijs Mekking 99f84ae56e return errTruncated after setting header bits (#442) 2017-01-30 10:53:01 +00:00
Richard Gibson 21314e1838 Fix TXT RDATA parsing (#421)
* 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
2016-12-02 09:34:49 +00:00
Preet Bhinder 3f1f7c8ec9 Fix a couple of comments (#386) 2016-10-03 19:18:08 +01:00
Miek Gieben e6b37d00af Cleanup and removals (#377)
* 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
2016-06-13 19:44:38 +01:00
Miek Gieben b51e305bc6 Remove reflection (#376)
Everything is generated. Remove all uses of packStruct/unpackStruct and
make the library reflectionless.
2016-06-12 21:06:46 +01:00
Miek Gieben dbffa4b057 Kill all reflection when packing/unpacking RR (#372)
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.
2016-06-12 18:31:50 +01:00
Miek Gieben 6ae3b9f061 Skip reflection for most types (#369)
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
2016-06-12 16:09:37 +01:00
Miek Gieben 331ecbbc51 Add RcodeBadCookie (23) 2016-06-12 13:10:24 +01:00
Michael Haro 1be7320498 Use t.Errorf in tests and make the error variable naming more consistent. (#367)
* 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.
2016-06-09 07:00:08 +01:00
Michael Haro a465e84f54 Use encoding/binary's conversion functions when possible. (#364)
* 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.
2016-06-08 16:38:42 +01:00
Miek Gieben 799de7044d Remove WKS support
Support for WKS was incomplete, i.e. len() method was incorrect.
Remove support for the record and handle it as an unknown one.

Fixes #361
2016-06-05 08:23:44 +01:00
Miek Gieben 907a4aef57 Generate pack/unpack for all RRs (#360)
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.
2016-06-05 07:53:12 +01:00
Roland Bracewell Shoemaker 3f53d75269 Seed math/rand with crypto/rand (#359)
* 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
2016-06-05 07:51:30 +01:00
Miek Gieben 475ab80867 Remove (most) reflection
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.
2016-06-03 12:45:22 +01:00
Miek Gieben f53eb22bfb Check length before packing OPT (#352)
fixes #351
2016-05-05 16:56:17 +01:00
Shumon Huque b534177a1a small patch for EDNS0 cookie support (#350)
* Add EDNS0 Cookie (option 10) support.

* Add EDNS0 Cookie processing.

* Fix nits.

* Add EDNS0 cookie support mention.
2016-05-03 16:19:28 +01:00
Matthijs Mekking 5107215070 Len returns the rr len of the uncompressed format. 2016-03-17 15:07:51 +01:00
Nick Galbreath 5cbabd2322 spelling 2016-01-19 14:23:11 -08:00
James Hartig 2d2c2ebcfc Instead of removing all RRs on Truncated, attempt to unpack 2015-11-01 15:51:09 -05:00
Filippo Valsorda 023972bb19 Expose TypeToRR 2015-10-16 23:36:49 +01:00
Filippo Valsorda d4a4e089d0 Generate programmatically per-type code, including .len()
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".
2015-10-07 05:48:12 +01:00
Miek Gieben 79547a0341 Add Dedup function
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.
2015-08-24 22:02:57 +01:00
Miek Gieben 9bf52083d1 golint fixes 2015-08-23 08:03:13 +01:00
Miek Gieben 21b35db538 Remove the NSAP record
The NSAP was not implemented correctly, see #239. Just remove it. It will still work as unknown RR.
2015-08-10 07:26:35 +01:00
Miek Gieben 8eb292db07 Doc update for future change in TC handling
Update the comment in msg.go#L1700 about the TC bit handling

Small cleanups.
2015-08-09 16:26:25 +01:00
Miek Gieben 58c5f4cf6e Small doc updates 2015-08-07 20:58:26 +01:00
Filippo Valsorda 40484667f4 rewrite NSEC bitmap [un]packing to account for out-of-order 2015-08-05 00:18:02 +01:00
Filippo Valsorda 2b564cd047 UnpackDomainName: fix infinite loop where it would lower 'off'
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].
2015-08-05 00:18:02 +01:00
Filippo Valsorda 77aa064ef9 packStructValue: rewrite dns:"wks" packing which was writing out of bounds 2015-08-05 00:18:02 +01:00