Re: [TLS] Servers sending CA names

2023-04-13 Thread Peter Gutmann
Ilari Liusvaara writes: >You mean overflow the maximum field size (64kB)? No, just the 16kB message size, so you get what should be a ~100-byte cert request that's 20-30kB long. The code assumed - and I know this is crazy talk here - that a 100-byte message would fit easily into a 16kB I/O

Re: [TLS] Servers sending CA names

2023-04-13 Thread Ilari Liusvaara
On Thu, Apr 13, 2023 at 02:35:50AM +, Peter Gutmann wrote: > Salz, Rich writes: > > >Is this generally used? Would things go badly if we stopped sending them? > > Just as a data point, in the SCADA world it seems to be universally ignored. > I've seen everything from servers that send a

Re: [TLS] Servers sending CA names

2023-04-13 Thread Achim Kraus
One purpose additional to the already mentioned selection of the "right" client certificate may be to truncate the sent client certificate path at such a CA certificate, though that certificate is already available at the server. If x509 is used at all for IoT, such a truncation may reduce the