CURLOPT_SSL_VERIFYPEER(3) curl_easy_setopt options CURLOPT_SSL_VERIFYPEER(3)NAMECURLOPT_SSL_VERIFYPEER - verify the peer's SSL certificate
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_VERIFYPEER, long
verify);
DESCRIPTION
Pass a long as parameter to enable or disable.
This option determines whether curl verifies the authenticity of the
peer's certificate. A value of 1 means curl verifies; 0 (zero) means it
doesn't.
When negotiating a TLS or SSL connection, the server sends a certifi‐
cate indicating its identity. Curl verifies whether the certificate is
authentic, i.e. that you can trust that the server is who the certifi‐
cate 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 deter‐
mined at build time) and you can specify alternate certificates with
the CURLOPT_CAINFO(3) option or the CURLOPT_CAPATH(3) option.
When CURLOPT_SSL_VERIFYPEER(3) 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 regard‐
less.
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 CURLOPT_SSL_VERIFYHOST(3) 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 CURLOPT_SSL_VERI‐
FYPEER(3) 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 communi‐
cating with the correct end-point.
DEFAULT
By default, curl assumes a value of 1.
PROTOCOLS
All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
EXAMPLE
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
/* Set the default value: strict certificate check please */
curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);
curl_easy_perform(curl);
}
AVAILABILITY
If built TLS enabled.
RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
if not.
SEE ALSOCURLOPT_SSL_VERIFYHOST(3),
libcurl 7.37.0 17 Jun 2014 CURLOPT_SSL_VERIFYPEER(3)
