On Thursday, May 23, 2024 9:56 AM, Wiebe Cazemier wrote:
>> From: "Neil Horman" <[email protected]>
>> from:
>> [ https://www.openssl.org/docs/man1.0.2/man3/SSL_CTX_set_mode.html |
>> https://www.openssl.org/docs/man1.0.2/man3/SSL_CTX_set_mode.html ]
>
>> SSL_MODE_AUTO_RETRY in non-blocking mode should cause
>> SSL_reaa/SSL_write to return -1 with an error code of
>> WANT_READ/WANT_WRITE until such time as the re-negotiation has
>> completed. I need to confirm thats the case in the code, but it seems
>> to be. If the underlying socket is in non-blocking mode, there should
>> be no way for calls to block in SSL_read/SSL_write on the socket read/write system
>call.
>
>I still don't really see what the difference is between SSL_MODE_AUTO_RETRY on or
>off in non-blocking mode?
>
>The person at [1] seems to have had a similar issue, and was convinced clearing
>SSL_MODE_AUTO_RETRY fixed it. But I agree, I don't know how it could be.
>OpenSSL would have to remove the O_NONBLOCK, or do select/poll, and I can't
>find it doing that.
>
>I hope it happens again soon and I'm around to attach a debugger.
I may be incorrect here, but my interpretation is as follows:
SSL_MODE_AUTO_RETRY on - if there is a packet ready to read on the socket, the packet is retrieved. Same for write. If not ready, because EWOULDBLOCK, the operation is retried automatically by OpenSSL.
SSL_MODE_AUTO_RETRY off - if there is a packet ready to read on the socket, the packet is retrieved. Same for write. If not ready, the OpenSSL operation reports an error.
Randall
lmpx.com only provides a reader for public news (NNTP) servers. It is not
affiliated with the servers or forums shown here and is not responsible for
the content of articles, which is written by their respective authors.