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.TH CURLOPT_SSL_OPTIONS 3 "January 29, 2019" "libcurl 7.64.0" "curl_easy_setopt options"

.SH NAME
CURLOPT_SSL_OPTIONS \- set SSL behavior options
.SH SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_OPTIONS, long bitmask);
.SH DESCRIPTION
Pass a long with a bitmask to tell libcurl about specific SSL behaviors.

\fICURLSSLOPT_ALLOW_BEAST\fP tells libcurl to not attempt to use any
workarounds for a security flaw in the SSL3 and TLS1.0 protocols.  If this
option isn't used or this bit is set to 0, the SSL layer libcurl uses may use a
work-around for this flaw although it might cause interoperability problems
with some (older) SSL implementations. WARNING: avoiding this work-around
lessens the security, and by setting this option to 1 you ask for exactly that.
This option is only supported for DarwinSSL, NSS and OpenSSL.

Added in 7.44.0:

\fICURLSSLOPT_NO_REVOKE\fP tells libcurl to disable certificate revocation
checks for those SSL backends where such behavior is present. \fBCurrently this
option is only supported for Schannel (the native Windows SSL library), with an
exception in the case of Windows' Untrusted Publishers blacklist which it seems
can't be bypassed.\fP This option may have broader support to accommodate other
SSL backends in the future.
https://curl.haxx.se/docs/ssl-compared.html
.SH DEFAULT
0
.SH PROTOCOLS
All TLS-based protocols
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
  /* weaken TLS only for use with silly servers */
  curl_easy_setopt(curl, CURLOPT_SSL_OPTIONS, CURLSSLOPT_ALLOW_BEAST |
                   CURLSSLOPT_NO_REVOKE);
  ret = curl_easy_perform(curl);
  curl_easy_cleanup(curl);
}
.fi
.SH AVAILABILITY
Added in 7.25.0
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLOPT_SSLVERSION "(3), " CURLOPT_SSL_CIPHER_LIST "(3), "