[tor-bugs] #28616 [Core Tor/Tor]: TLS internal error running Tor 0.3.4.9 on Debian Buster (OpenSSL 1.1.1a)

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#28616: TLS internal error running Tor 0.3.4.9 on Debian Buster (OpenSSL 1.1.1a)
--------------------------+------------------------------
 Reporter:  filippo       |          Owner:  (none)
     Type:  defect        |         Status:  new
 Priority:  Medium        |      Milestone:
Component:  Core Tor/Tor  |        Version:  Tor: 0.3.4.9
 Severity:  Normal        |     Resolution:
 Keywords:                |  Actual Points:
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
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Comment (by nickm):

 Found it!  This is an issue with this change in openssl 1.1a from commit
 ec0c5f5693e39c5:
 {{{
 +/*
 + * RFC 8446, 7.1 Key Schedule, says:
 + * Note: With common hash functions, any label longer than 12 characters
 + * requires an additional iteration of the hash function to compute.
 + * The labels in this specification have all been chosen to fit within
 + * this limit.
 + */
 +#define TLS13_MAX_LABEL_LEN     12
 }}}

 I've opened an OpenSSL issue at
 https://github.com/openssl/openssl/issues/7712 .  This does not seem like
 something we can work around ourselves.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/28616#comment:2>
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