CURLOPT_SSL_OPTIONS(3)

1CURLOPT_SSL_OPTIONS(3)     curl_easy_setopt options     CURLOPT_SSL_OPTIONS(3)
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NAME

6       CURLOPT_SSL_OPTIONS - set SSL behavior options
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLcode  curl_easy_setopt(CURL *handle, CURLOPT_SSL_OPTIONS, long bit‐
12       mask);
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DESCRIPTION

15       Pass a long with a bitmask to tell libcurl about  specific  SSL  behav‐
16       iors.
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18       CURLSSLOPT_ALLOW_BEAST  tells  libcurl  to not attempt to use any work‐
19       arounds for a security flaw in the SSL3 and TLS1.0 protocols.  If  this
20       option  isn't  used or this bit is set to 0, the SSL layer libcurl uses
21       may use a work-around for this flaw although it might cause  interoper‐
22       ability problems with some (older) SSL implementations. WARNING: avoid‐
23       ing this work-around lessens the security, and by setting  this  option
24       to  1 you ask for exactly that.  This option is only supported for Dar‐
25       winSSL, NSS and OpenSSL.
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27       Added in 7.44.0:
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29       CURLSSLOPT_NO_REVOKE tells libcurl to  disable  certificate  revocation
30       checks  for  those  SSL  backends  where such behavior is present. This
31       option is only supported for Schannel (the native Windows SSL library),
32       with  an  exception in the case of Windows' Untrusted Publishers black‐
33       list which it seems can't be bypassed.
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DEFAULT

36       0
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PROTOCOLS

39       All TLS-based protocols
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EXAMPLE

42       CURL *curl = curl_easy_init();
43       if(curl) {
44         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
45         /* weaken TLS only for use with silly servers */
46         curl_easy_setopt(curl, CURLOPT_SSL_OPTIONS, CURLSSLOPT_ALLOW_BEAST |
47                          CURLSSLOPT_NO_REVOKE);
48         ret = curl_easy_perform(curl);
49         curl_easy_cleanup(curl);
50       }
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AVAILABILITY

53       Added in 7.25.0
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RETURN VALUE

56       Returns CURLE_OK if the option is supported,  and  CURLE_UNKNOWN_OPTION
57       if not.
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