1---
2c: Copyright (C) Daniel Stenberg, <daniel.se>, et al.
3SPDX-License-Identifier: curl
4Title: CURLOPT_PROXY_CRLFILE
5Section: 3
6Source: libcurl
7See-also:
8  - CURLOPT_PROXY_SSL_VERIFYHOST (3)
9  - CURLOPT_PROXY_SSL_VERIFYPEER (3)
10  - CURLOPT_SSL_VERIFYHOST (3)
11  - CURLOPT_SSL_VERIFYPEER (3)
12---
13
14# NAME
15
16CURLOPT_PROXY_CRLFILE - HTTPS proxy Certificate Revocation List file
17
18# SYNOPSIS
19
20~~~c
21#include <curl/curl.h>
22
23CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_CRLFILE, char *file);
24~~~
25
26# DESCRIPTION
27
28This option is for connecting to an HTTPS proxy, not an HTTPS server.
29
30Pass a char pointer to a null-terminated string naming a *file* with the
31concatenation of CRL (in PEM format) to use in the certificate validation that
32occurs during the SSL exchange.
33
34When curl is built to use GnuTLS, there is no way to influence the use of CRL
35passed to help in the verification process. When libcurl is built with OpenSSL
36support, X509_V_FLAG_CRL_CHECK and X509_V_FLAG_CRL_CHECK_ALL are both set,
37requiring CRL check against all the elements of the certificate chain if a CRL
38file is passed.
39
40This option makes sense only when used in combination with the
41CURLOPT_PROXY_SSL_VERIFYPEER(3) option.
42
43A specific error code (*CURLE_SSL_CRL_BADFILE*) is defined with the option. It
44is returned when the SSL exchange fails because the CRL file cannot be loaded.
45A failure in certificate verification due to a revocation information found in
46the CRL does not trigger this specific error.
47
48The application does not have to keep the string around after setting this
49option.
50
51# DEFAULT
52
53NULL
54
55# PROTOCOLS
56
57Used with HTTPS proxy.
58
59# EXAMPLE
60
61~~~c
62int main(void)
63{
64  CURL *curl = curl_easy_init();
65  if(curl) {
66    CURLcode res;
67    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
68    curl_easy_setopt(curl, CURLOPT_PROXY, "https://localhost:80");
69    curl_easy_setopt(curl, CURLOPT_PROXY_CRLFILE, "/etc/certs/crl.pem");
70    res = curl_easy_perform(curl);
71    curl_easy_cleanup(curl);
72  }
73}
74~~~
75
76# AVAILABILITY
77
78Added in 7.52.0
79
80# RETURN VALUE
81
82Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, or
83CURLE_OUT_OF_MEMORY if there was insufficient heap space.
84