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Re: Difference between CURLOPT_SSL_VERIFYHOST and CURLOPT_SSL_VERIFYPEER?

From: Vadim Grinshpun <vgrinshp_at_akamai.com>
Date: Tue, 07 Jul 2015 13:23:36 -0400

On 7/7/15 10:12 AM, Dr. Roger Cuypers wrote:
>
> Greetings,
>
> can someone explain me what the difference between
> CURLOPT_SSL_VERIFYHOST and CURLOPT_SSL_VERIFYPEER is in the context of
> a client program? For a client, the host and the peer are both the server.
>
> The only difference I can make out at first glance is that verifypeer
> may cause the connection to fail while verifyhost is tested later.
>
The difference is visible if you look at the summary of each option:
CURLOPT_SSL_VERIFYPEER - verify the peer's SSL certificate
CURLOPT_SSL_VERIFYHOST - verify the certificate's name against host

Note the difference in the description.
VERIFYPEER basically makes sure the certificate itself is valid (i.e.,
signed by a trusted CA, the certificate chain is complete, etc).
VERIFYHOST checks that the host you're talking to is the host named in
the certificate.

(using a driver's license analogy: VERIFYPEER makes sure the license
itself is not fake; VERIFYHOST makes sure the person whose name and
photo are on the license is the same as the person showing the license :)

HTH,
-Vadim

> Regards
>
>
>
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Received on 2015-07-07