Don't change client random in Client Hello in its second flight #4490
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richsalz
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Oct 8, 2017
dot-asm
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mattcaswell
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Oct 9, 2017
ssl/statem/statem_clnt.c
Outdated
| @@ -1036,7 +1036,7 @@ int tls_construct_client_hello(SSL *s, WPACKET *pkt) | |||
| } | |||
| } | |||
| } else | |||
| i = 1; | |||
| i = s->hello_retry_request == 0; | |||
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While we are touching this line anyway, could we enclose it in {}. The style guide says that if one branch of an if uses {} then both should.
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"{}" added in 5187e42
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Note also that this is only a partial fix for #4292. It addresses the random problem, but not the changing of extensions. That's ok though - we can address that in some later PR. |
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Yes, this is a partial fix. |
mattcaswell
approved these changes
Oct 9, 2017
mattcaswell
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approval: done
kaduk
approved these changes
Oct 9, 2017
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Should I push squashed commit? |
levitte
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Oct 10, 2017
Reviewed-by: Ben Kaduk <kaduk@mit.edu> Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from #4490)
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Squashed and pushed. A test would be nice, but I've pushed this for now anyway |
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Addresses #4292
It looks like https://tools.ietf.org/html/draft-ietf-tls-tls13-21#section-4.1.2 does not explicitly allow a client to send the difference client random in its second flight Client Hello.
At least picotls checks they are the same, and aborts a handshake if they are different.
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