How to Use Secure Sockets in C on Linux

netprivacypro.com

I would have liked to see the logic on client side to decide if the certificate presented by the server is valid.

I'm a little surprised the OpenSSL API doesn't force you to consider this by default, but indeed it does not: https://www.openssl.org/docs/manmaster/man3/SSL_CTX_new.html...

> On session establishment, by default, no peer credentials verification is done. This must be explicitly requested, typically using SSL_CTX_set_verify(3).

Aside: According to those docs, SSLv23_client_method() is deprecated.

Yeah, not verifying server cert or OCSP/CRLs is a problem. DNS attacks can redirect and you'd be none the wiser.

The page was updated to include that.

Well done!

This is a really nice part 1. I think a series building from this up to what would be considered "secure" in modern day, with the other topics already mentioned in comments here and on the article, would be awesome. I could easily see it becoming a very popular resource among students or new devs who are solving these problems for the first time themselves. The writing is very clear and concise.

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