Cannot connect to IP addresses on OpenBSD (LibreSSL)

[matteocorti]

Describe the bug

The script fails to connect to hosts specified with an IP address on OpenBSD with LibreSSL

To Reproduce

./check_ssl_cert -H 138.201.94.172
SSL_CERT CRITICAL 138.201.94.172:443: SSL error: Unable to set TLS servername extension. 

Expected behavior

/check_ssl_cert -H 138.201.94.172
SSL_CERT OK - 138.201.94.172:443, https, x509 certificate 'corti.li' from 'Let's Encrypt' valid until Feb  1 19:04:54 2024 GMT (expires in 72 days)|days_chain_elem1=72;20;15;; days_chain_elem2=664;20;15;; days_chain_elem3=314;20;15;;

System (please complete the following information):

• OS: OpenBSD
• OS version: 7.4
• check_ssl_cert version: 2.76.0
• OpenSSL version (openssl version): LibreSSL 3.8.2

Additional context/output

LibreSSL does not accept an IP as -servername:

$ /usr/bin/openssl s_client     -crlf  -connect 138.201.94.172:443 -servername 138.201.94.172   -showcerts -verify 6
verify depth is 6
Unable to set TLS servername extension.
77968620024:error:1404E13F:SSL routines:ST_BEFORE_CONNECT:ssl3 ext invalid servername:/usr/src/lib/libssl/s3_lib.c:1838:

[matteocorti]

Fixed with 7f0a507