CURLOPT_PROXY_SSL_VERIFYPEER(3)

1CURLOPT_PROXY_SSL_VERIFYPEER(3)     libcurl    CURLOPT_PROXY_SSL_VERIFYPEER(3)
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NAME

6       CURLOPT_PROXY_SSL_VERIFYPEER - verify the proxy's SSL certificate
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_SSL_VERIFYPEER,
12                                 long verify);
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DESCRIPTION

15       Pass a long as parameter set to 1L to enable or 0L to disable.
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17       This  option tells curl to verify the authenticity of the HTTPS proxy's
18       certificate. A value of 1 means curl verifies; 0 (zero) means  it  does
19       not.
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21       This is the proxy version of CURLOPT_SSL_VERIFYPEER(3) that is used for
22       ordinary HTTPS servers.
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24       When negotiating a TLS or SSL connection, the server sends  a  certifi‐
25       cate  indicating its identity. Curl verifies whether the certificate is
26       authentic, i.e. that you can trust that the server is who the  certifi‐
27       cate says it is.  This trust is based on a chain of digital signatures,
28       rooted in certification authority (CA) certificates you  supply.   curl
29       uses  a  default bundle of CA certificates (the path for that is deter‐
30       mined at build time) and you can specify  alternate  certificates  with
31       the  CURLOPT_PROXY_CAINFO(3)  option or the CURLOPT_PROXY_CAPATH(3) op‐
32       tion.
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34       When CURLOPT_PROXY_SSL_VERIFYPEER(3) is enabled, and  the  verification
35       fails to prove that the certificate is authentic, the connection fails.
36       When the option is zero, the peer certificate verification succeeds re‐
37       gardless.
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39       Authenticating  the  certificate  is  not  enough  to be sure about the
40       server. You typically also want to ensure that the server is the server
41       you  mean  to  be  talking to.  Use CURLOPT_PROXY_SSL_VERIFYHOST(3) for
42       that. The check that the host name in the certificate is valid for  the
43       host  name  you  are  connecting  to  is done independently of the CUR‐
44       LOPT_PROXY_SSL_VERIFYPEER(3) option.
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46       WARNING: disabling verification of the certificate allows bad  guys  to
47       man-in-the-middle  the  communication without you knowing it. Disabling
48       verification makes the communication insecure. Just  having  encryption
49       on a transfer is not enough as you cannot be sure that you are communi‐
50       cating with the correct end-point.
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DEFAULT

53       1
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PROTOCOLS

56       All
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EXAMPLE

59       CURL *curl = curl_easy_init();
60       if(curl) {
61         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
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63         /* Set the default value: strict certificate check please */
64         curl_easy_setopt(curl, CURLOPT_PROXY_SSL_VERIFYPEER, 1L);
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66         curl_easy_perform(curl);
67       }
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AVAILABILITY

70       Added in 7.52.0
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72       If built TLS enabled.
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RETURN VALUE

75       Returns CURLE_OK if the option is supported,  and  CURLE_UNKNOWN_OPTION
76       if not.
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