This change factors out the code related to SOCKS protocol version 5
from the golang/x/net/proxy package and provides new SOCKS-specific
API to fix the following:
- inflexbility of forward proxy connection setup; e.g., no support for
  context-based deadline or canceling, no support for dial deadline,
  no support for working with external authentication mechanisms,
- useless error values for troubleshooting.

The new package socks is supposed to be used by the net/http package
of standard library and proxy package of golang.org/x/net repository.

Fixes golang/go#11682.
Updates golang/go#17759.
Updates golang/go#19354.
Updates golang/go#19688.
Fixes golang/go#21333.

Change-Id: I24098ac8522dcbdceb03d534147c5101ec9e7350
Reviewed-on: https://go-review.googlesource.com/38278
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The net.Listener interface specifies that on Close:
// Any blocked Accept operations will be unblocked and return errors.

Fixes golang/go#24458

Change-Id: I4a61a79db9579a40b536aa65c8077da87aa25156
Reviewed-on: https://go-review.googlesource.com/101535Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Change-Id: I008840a981179bb9397735b88155d7476ae76599
Reviewed-on: https://go-review.googlesource.com/101296Reviewed-by: Ian Gudger <igudger@google.com>

This change introduces OPTResourse type to support DNS messages
containing various extension options as defined in RFC 6891.
Parsing and building OPT pseudo records requires allocations like TXT
records.

Also adds DNSSECAllowed, ExtendedRCode and SetEDNS0 methods to
ResourceHeader for convenience.

Updates golang/go#6464.
Updates golang/go#16218.

Change-Id: Ib72cea277201e4122c6b5effa320084ff351c886
Reviewed-on: https://go-review.googlesource.com/47170Reviewed-by: Ian Gudger <igudger@google.com>

This change implements support for extended echo request and reply
messages, and interface identification object that can be used to test
the status of a probed interface via a proxy interface from a probing
interface as defined in RFC 8335.

It's package user's responsibility to make a complete RFC-compliant
PROBE initiator implementation using ipv4, ipv6 and icmp packages of
x/net repository.

Fixes golang/go#24440.

Change-Id: I87ab8a7581c4d41a0c579805b0e3043e48ac85f0
Reviewed-on: https://go-review.googlesource.com/63999Reviewed-by: Ian Lance Taylor <iant@golang.org>

Updates golang/go#24440.

Change-Id: Idbe22ca853ea4771bb979782ef3bac8b03c59b87
Reviewed-on: https://go-review.googlesource.com/63998
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Updates golang/go#24440.

Change-Id: Icd7dbb9b6748ba8dd165eec1c0021650b7f4d97d
Reviewed-on: https://go-review.googlesource.com/63997
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Updates golang/go#24440.

Change-Id: Ic56bb1add57831d6c94f148d209417be5aa22cb2
Reviewed-on: https://go-review.googlesource.com/63996
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This change reorganizes the existing test cases for supporting new
messages and extension in upcoming CLs. It also renames ping_test.go
to diag_test.go for clarification.

Updates golang/go#24440.

Change-Id: I5753a2ddbe76423d996a37f583fcf32b65d380e9
Reviewed-on: https://go-review.googlesource.com/63995Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates golang/go#10622

Change-Id: Iadf0ff0fd223a315130941464040aef5e71f6130
Reviewed-on: https://go-review.googlesource.com/100055
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Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Updates golang/go#24185

Change-Id: Ifbd5b9c8c8bb11635c49a390a8deda8bfed8e849
Reviewed-on: https://go-review.googlesource.com/100685Reviewed-by: Ian Lance Taylor <iant@golang.org>

Previously, we only accepted a single string for TXT records and then
chunked it into 255 byte segments. This is wrong. TXT records are a
sequence of strings, each up to 255 bytes.

Updates golang/go#24288

Change-Id: Ib2c085ec127ccecf0c7bda930100b667cabc1f4b
Reviewed-on: https://go-review.googlesource.com/100196Reviewed-by: Matthew Dempsky <mdempsky@google.com>
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Fixes golang/go#24346

Change-Id: I6b32d79135c0843d62425f4cc4c18f5a0eb9efd3
Reviewed-on: https://go-review.googlesource.com/100155Reviewed-by: Ian Lance Taylor <iant@golang.org>

CL generated mechanically with github.com/mdempsky/unconvert.

Change-Id: I22eea0b991462dd00f3fa28073a8b886e19bc068
Reviewed-on: https://go-review.googlesource.com/100095
Run-TryBot: Kunpei Sakai <namusyaka@gmail.com>
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Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>

This change protects fields mutated by Trace methods with a mutex.
In particular it fixes races caused by concurrent calls to IsError,
and viewing active traces in /debug/requests.

Includes changes from CL/67730.

Updates golang/go#24231

Change-Id: I07db54c2642efe0ea0e3ffeb54ec796ae51e70ef
Reviewed-on: https://go-review.googlesource.com/98535
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Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>

So https://http2.golang.org/reqinfo has a RemoteAddr of the client's
actual IP address.

Change-Id: I9db52b2f451ad937d013dd78078e4228e732ffe0
Reviewed-on: https://go-review.googlesource.com/99235Reviewed-by: David Anderson <danderson@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates golang/go#16218

Change-Id: I078395a8c3967c2ac6a6e86f1528a431346b8ff4
Reviewed-on: https://go-review.googlesource.com/98755Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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The new appending behavior is required for an efficient DNS client.

(*Builder).Start was intended to append, but didn't. This was a mistake
(all tests and examples assumed that it did).

In addition, message compression when appending has been fixed.

Updates golang/go#16218

Change-Id: I3f42aa6e653e2990fa90368a2803e588ea15b85a
Reviewed-on: https://go-review.googlesource.com/97716Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Change-Id: I5dc9a8fa647ccb34caae9a1342012cb36d1fcc22
Reviewed-on: https://go-review.googlesource.com/94975Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

See https://html.spec.whatwg.org/multipage/parsing.html#the-list-of-active-formatting-elements

Updates golang/go#23071

Change-Id: I015c394ed34d721e9e4a4d3e797d06d750c1864e
Reviewed-on: https://go-review.googlesource.com/94837Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates golang/go#23071

See https://html.spec.whatwg.org/multipage/

Change-Id: I1bde6e07ae9270ba7b320474b9bec8ec09a79f16
Reviewed-on: https://go-review.googlesource.com/94355Reviewed-by: Nigel Tao <nigeltao@golang.org>

Replace references to the obsoleted RFC 2616 with references to RFC
7230 through 7235, to avoid unnecessary confusion.

Updates golang/go#21974

Change-Id: Idbe3e73199f0bef9dbdbe1b75c39382799cd646c
Reviewed-on: https://go-review.googlesource.com/94555Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Update the list to revision 0f3b07d9aab6d6c9fe74990af98316468d40f488
(2018-01-25T09:22:16Z).

Change-Id: I3a41aeef98e1245cfd7f7fa5958f986ff313e65a
Reviewed-on: https://go-review.googlesource.com/91836Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We mustn't use data from p.header to pre-allocate slices for Message.Question, etc.
Otherwise an attacker can force the allocation of several MiB per parsed message,
which can lead to a DoS via putting pressure on the GC.

Fixes golang/go#23214

Change-Id: I6c99577f625b08331b438533adb6b8167bcd1ec5
Reviewed-on: https://go-review.googlesource.com/85135Reviewed-by: Ian Gudger <igudger@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I1cdb799ce509f94e3541bf3e94cb75b3797269f6
Reviewed-on: https://go-review.googlesource.com/91517Reviewed-by: Andrew Bonventre <andybons@golang.org>

This makes HTTP challenges work on https://http2.golang.org/ since
LetsEncrypted disabled the TLS-SNI challenges.

Also, move it from a systemd unit on CoreOS to GKE.

Updates golang/go#23627
Fixes golang/go#23034

Change-Id: Id8348e9e56ab43e277f1e12d563fd8fc490d6211
Reviewed-on: https://go-review.googlesource.com/91495Reviewed-by: Andrew Bonventre <andybons@golang.org>

Fixes golang/go#23507

Change-Id: Id39b28f211dfdb6a5464752b8b62e2528b46286b
Reviewed-on: https://go-review.googlesource.com/91315Reviewed-by: David Symonds <dsymonds@golang.org>

iana.org, www.iana.org and data.iana.org all present a valid TLS
certificate, so let's use it when fetching data to avoid errors in
transit.

Change-Id: I1f295442d24a221fe2b722c4782dceee38b960ec
Reviewed-on: https://go-review.googlesource.com/89415Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I39359b5fa52faf5b69005ba47b58be3beec16c4e
Reviewed-on: https://go-review.googlesource.com/87515Reviewed-by: David Symonds <dsymonds@golang.org>

In a given program there may be two separate copies of
ErrNoCachedConn: the h2_bundle.go version in net/http, and the user's
golang.org/x/net/http2 version. We need to be able to detect either
in net/http.

This CL adds a function to report whether an error value represents
that type of error, and then a subsequent CL to net/http will use it
instead of ==.

Updates golang/go#22091

Change-Id: I86f1e20704eee29b8980707b700d7a290107dfd4
Reviewed-on: https://go-review.googlesource.com/87297Reviewed-by: Tom Bergan <tombergan@google.com>

s/packet/message/g

Change-Id: I2adf809bb4b90e78cf894e4cb6832c117042deb7
Reviewed-on: https://go-review.googlesource.com/65830
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Tests will be in net/http in a separate CL.

Updates golang/go#23010

Change-Id: I91a6875b9a59b33a3c669e73dd6632ac523eb9f6
Reviewed-on: https://go-review.googlesource.com/86255Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Change-Id: Ic4e0dc9ef27522606061e2ab212a9d6b2b40dd64
Reviewed-on: https://go-review.googlesource.com/83435
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
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This reverts commit 5c0ad186.

Change-Id: I1b6fac0f88816f4464e732d2f8a3d5510decb255
Reviewed-on: https://go-review.googlesource.com/82697Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>

This reverts commit eb818ae5.

Change-Id: I2034119c7a512c7ceffa72e837e4bed3ff01ed8d
Reviewed-on: https://go-review.googlesource.com/82696Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>

This reverts commit a0df0836.

Change-Id: Iec23fd267fd74470dbc827aa6422c6e598b6e86c
Reviewed-on: https://go-review.googlesource.com/82695Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>

Change-Id: I21ec68eef6cf14e0ff30b437d717d46e1dc9fea5
Reviewed-on: https://go-review.googlesource.com/82456
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Change-Id: Ide52e52d6859378bc12bb97081f63d657cb2a76f
Reviewed-on: https://go-review.googlesource.com/82455
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Change-Id: I7c88abdd74effca1cd8dd72970f0bee914e82fc2
Reviewed-on: https://go-review.googlesource.com/82457
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Fixes golang/go#22301.

Change-Id: I29f4f8806e10aad59cf7f984fd346acc216b0fd0
Reviewed-on: https://go-review.googlesource.com/79855
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>