| commit | a10017c548b0805eb98e7847c37370dbd37cd8d6 | [log] [tgz] |
|---|---|---|
| author | David Benjamin <davidben@google.com> | Wed Jun 16 16:00:13 2021 -0400 |
| committer | Boringssl LUCI CQ <boringssl-scoped@luci-project-accounts.iam.gserviceaccount.com> | Thu Jun 24 00:58:33 2021 +0000 |
| tree | 40a881aaed9d2ede15b1290b3223a8e1291736e8 | |
| parent | 10a76acb0f2564a525887f88c4e3aea10f3fc1f2 [diff] |
Reduce bouncing on the cache lock in ssl_update_cache. ssl_update_cache takes the cache lock to add to the session cache, releases it, and then immediately takes and releases the lock to increment handshakes_since_cache_flush. Then, in 1/255 connections, does the same thing again to flush stale sessions. Merge the first two into one lock. In doing so, move ssl_update_cache to ssl_session.cc, so it can access a newly-extracted add_session_lock. Also remove the mode parameter (the SSL knows if it's a client or server), and move the established_session != session check to the caller, which more directly knows whether there was a new session. Also add some TSan coverage for this path in the tests. In an earlier iteration of this patch, I managed to introduce a double-locking bug because we weren't testing it at all. Confirmed this test catches both double-locking and insufficient locking. (It doesn't seem able to catch using a read lock instead of a write lock in SSL_CTX_flush_sessions, however. I suspect the hash table is distributing the cells each thread touches.) Update-Note: This reshuffles some locks around the session cache. (Hopefully for the better.) Change-Id: I78dca53fda74e036b90110cca7fbcc306a5c8ebe Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48133 Commit-Queue: David Benjamin <davidben@google.com> Reviewed-by: Adam Langley <agl@google.com>
BoringSSL is a fork of OpenSSL that is designed to meet Google's needs.
Although BoringSSL is an open source project, it is not intended for general use, as OpenSSL is. We don't recommend that third parties depend upon it. Doing so is likely to be frustrating because there are no guarantees of API or ABI stability.
Programs ship their own copies of BoringSSL when they use it and we update everything as needed when deciding to make API changes. This allows us to mostly avoid compromises in the name of compatibility. It works for us, but it may not work for you.
BoringSSL arose because Google used OpenSSL for many years in various ways and, over time, built up a large number of patches that were maintained while tracking upstream OpenSSL. As Google's product portfolio became more complex, more copies of OpenSSL sprung up and the effort involved in maintaining all these patches in multiple places was growing steadily.
Currently BoringSSL is the SSL library in Chrome/Chromium, Android (but it's not part of the NDK) and a number of other apps/programs.
Project links:
There are other files in this directory which might be helpful: