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Whether to verify the DOH SSL certificate.

Component Version macOS Windows Linux Server iOS SDK
CURL 11.2 ✅ Yes ✅ Yes ✅ Yes ✅ Yes ✅ Yes
MBS( "CURL.SetOptionDOHSSLVerifyPeer"; curl; Value )   More


Parameter Description Example
curl The CURL session handle. $curl
Value The new setting. 1


Returns OK or error.


Whether to verify the DOH SSL certificate.
Pass 1 to enable or 0 to disable.
This option tells curl to verify the authenticity of the DOH (DNS-over-HTTPS) server's certificate. A value of 1 means curl verifies; 0 (zero) means it doesn't.
This option is the DOH equivalent of CURL.SetOptionSSLVerifyPeer and only affects requests to the DOH server.
When negotiating a TLS or SSL connection, the server sends a certificate indicating its identity. Curl verifies whether the certificate is authentic, i.e. that you can trust that the server is who the certificate says it is. This trust is based on a chain of digital signatures, rooted in certification authority (CA) certificates you supply. curl uses a default bundle of CA certificates (the path for that is determined at build time) and you can specify alternate certificates with the CURL.SetOptionCAInfo option or the CURL.SetOptionCAPATH option.
When CURL.SetOptionDOHSSLVerifyPeer is enabled, and the verification fails to prove that the certificate is authentic, the connection fails. When the option is zero, the peer certificate verification succeeds regardless.
Authenticating the certificate is not enough to be sure about the server. You typically also want to ensure that the server is the server you mean to be talking to. Use CURL.SetOptionDOHSSLVerifyHost for that. The check that the host name in the certificate is valid for the host name you're connecting to is done independently of the CURL.SetOptionDOHSSLVerifyPeer option.

WARNING: disabling verification of the certificate allows bad guys to man-in-the-middle the communication without you knowing it. Disabling verification makes the communication insecure. Just having encryption on a transfer is not enough as you cannot be sure that you are communicating with the correct end-point.

See also DOH_SSL_VERIFYPEER option in CURL manual.

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Created 31st March 2021, last changed 31st March 2021

CURL.SetOptionDOHSSLVerifyHost - CURL.SetOptionDOHSSLVerifyStatus