Re: Blocking on a non-blocking socket?
Wiebe Cazemier via openssl-users <[email protected]>
| Newsgroups | gmane.comp.encryption.openssl.user |
|---|---|
| Message-ID | <[email protected]> |
Hi Neil, ----- Original Message ----- > From: "Neil Horman" <[email protected]> > To: "Wiebe Cazemier" <[email protected]> > Cc: "udhayakumar" <udhayakumar-lPYBU9dLbzqBUy7/[email protected]>, [email protected] > Sent: Thursday, 23 May, 2024 23:42:18 > Subject: Re: Blocking on a non-blocking socket? > 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. Regards, Wiebe [1] https://github.com/alanxz/rabbitmq-c/issues/586