Constant openssl::ssl::SSL_MODE_NO_AUTO_CHAIN

pub const SSL_MODE_NO_AUTO_CHAIN: SslMode = SslMode{bits: ffi::SSL_MODE_NO_AUTO_CHAIN,}

Disables automatic chain building when verifying a peer's certificate.

TLS peers are responsible for sending the entire certificate chain from the leaf to a trusted root, but some will incorrectly not do so. OpenSSL will try to build the chain out of certificates it knows of, and this option will disable that behavior.