Extremely large RSA keys in certificate chains can cause a client/server
to expend significant CPU time verifying signatures. Limit this by
restricting the size of RSA keys transmitted during handshakes to <=
8192 bits.
Based on a survey of publicly trusted RSA keys, there are currently only
three certificates in circulation with keys larger than this, and all
three appear to be test certificates that are not actively deployed. It
is possible there are larger keys in use in private PKIs, but we target
the web PKI, so causing breakage here in the interests of increasing the
default safety of users of crypto/tls seems reasonable.
Thanks to Mateusz Poliwczak for reporting this issue.
Fixes#61460
Fixes CVE-2023-29409
Change-Id: Ie35038515a649199a36a12fc2c5df3af855dca6c
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1912161
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Tatiana Bradley <tatianabradley@google.com>
Run-TryBot: Roland Shoemaker <bracewell@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/515257
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
This change updates the makeClientHello logic to only advertise TLS
1.3 ciphers when tls.Config.MinVersion is set to tls.VersionTLS13
(i.e the client only supports TLS 1.3). Previously, TLS 1.2 ciphers
would be included in the client hello message.
Fixes#57771
Change-Id: Ife4123037b0a4609578ffffb1cdf1e1d4e0a8df6
GitHub-Last-Rev: 45f4275
GitHub-Pull-Request: #49293
Reviewed-on: https://go-review.googlesource.com/c/go/+/360794
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Run-TryBot: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Marten Seemann <martenseemann@gmail.com>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
We used to inconsistently run certificate verification on the server on
resumption, but not on the client. This made TLS 1.3 resumption pretty
much useless, as it didn't save bytes, CPU, or round-trips.
This requires serializing the verified chains into the session ticket,
so it's a tradeoff making the ticket bigger to save computation (and for
consistency).
The previous behavior also had a "stickyness" issue: if a ticket
contained invalid certificates, they would be used even if the client
had in the meantime configured valid certificates for a full handshake.
We also didn't check expiration on the client side on resumption if
InsecureSkipVerify was set. Again for consistency, we do that now.
Also, we used to run VerifyPeerCertificates on resumption even if
NoClientCerts was set.
Fixes#31641
Change-Id: Icc88269ea4adb544fa81158114aae76f3c91a15f
Reviewed-on: https://go-review.googlesource.com/c/go/+/497895
Reviewed-by: Damien Neil <dneil@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
All OpenSSL tests now test operation with EMS. To test a handshake
*without* EMS we need to pass -Options=-ExtendedMasterSecret which is
only available in OpenSSL 3.1, which breaks a number of other tests.
Updates #43922
Change-Id: Ib9ac79a1d03fab6bfba5fe9cd66689cff661cda7
Reviewed-on: https://go-review.googlesource.com/c/go/+/497376
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Damien Neil <dneil@google.com>
Another internal change, that allows exposing the new APIs easily in
following CLs.
For #60105
Change-Id: I9c61b9f6e9d29af633f952444f514bcbbe82fe4e
Reviewed-on: https://go-review.googlesource.com/c/go/+/496819
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
Run-TryBot: Filippo Valsorda <filippo@golang.org>
Add a QUICConn type for use by QUIC implementations.
A QUICConn provides unencrypted handshake bytes and connection
secrets to the QUIC layer, and receives handshake bytes.
For #44886
Change-Id: I859dda4cc6d466a1df2fb863a69d3a2a069110d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/493655
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Run-TryBot: Damien Neil <dneil@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Marten Seemann <martenseemann@gmail.com>
Message marshalling makes use of BytesOrPanic a lot, under the
assumption that it will never panic. This assumption was incorrect, and
specifically crafted handshakes could trigger panics. Rather than just
surgically replacing the usages of BytesOrPanic in paths that could
panic, replace all usages of it with proper error returns in case there
are other ways of triggering panics which we didn't find.
In one specific case, the tree routed by expandLabel, we replace the
usage of BytesOrPanic, but retain a panic. This function already
explicitly panicked elsewhere, and returning an error from it becomes
rather painful because it requires changing a large number of APIs.
The marshalling is unlikely to ever panic, as the inputs are all either
fixed length, or already limited to the sizes required. If it were to
panic, it'd likely only be during development. A close inspection shows
no paths for a user to cause a panic currently.
This patches ends up being rather large, since it requires routing
errors back through functions which previously had no error returns.
Where possible I've tried to use helpers that reduce the verbosity
of frequently repeated stanzas, and to make the diffs as minimal as
possible.
Thanks to Marten Seemann for reporting this issue.
Fixes#58001
Fixes CVE-2022-41724
Change-Id: Ieb55867ef0a3e1e867b33f09421932510cb58851
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1679436
Reviewed-by: Julie Qiu <julieqiu@google.com>
TryBot-Result: Security TryBots <security-trybots@go-security-trybots.iam.gserviceaccount.com>
Run-TryBot: Roland Shoemaker <bracewell@google.com>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/468125
Run-TryBot: Michael Pratt <mpratt@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Michael Pratt <mpratt@google.com>
