CURLOPT_PROXY_ISSUERCERT.md (2358B)
1 --- 2 c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3 SPDX-License-Identifier: curl 4 Title: CURLOPT_PROXY_ISSUERCERT 5 Section: 3 6 Source: libcurl 7 See-also: 8 - CURLOPT_ISSUERCERT (3) 9 - CURLOPT_PROXY_SSL_VERIFYHOST (3) 10 - CURLOPT_PROXY_SSL_VERIFYPEER (3) 11 - CURLOPT_SSL_VERIFYHOST (3) 12 - CURLOPT_SSL_VERIFYPEER (3) 13 Protocol: 14 - TLS 15 TLS-backend: 16 - OpenSSL 17 - GnuTLS 18 Added-in: 7.71.0 19 --- 20 21 # NAME 22 23 CURLOPT_PROXY_ISSUERCERT - proxy issuer SSL certificate filename 24 25 # SYNOPSIS 26 27 ~~~c 28 #include <curl/curl.h> 29 30 CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_ISSUERCERT, char *file); 31 ~~~ 32 33 # DESCRIPTION 34 35 Pass a char pointer to a null-terminated string naming a *file* holding a CA 36 certificate in PEM format. If the option is set, an additional check against 37 the peer certificate is performed to verify the issuer of the HTTPS proxy is 38 indeed the one associated with the certificate provided by the option. This 39 additional check is useful in multi-level PKI where one needs to enforce that 40 the peer certificate is from a specific branch of the tree. 41 42 This option makes sense only when used in combination with the 43 CURLOPT_PROXY_SSL_VERIFYPEER(3) option. Otherwise, the result of the check is 44 not considered as failure. 45 46 A specific error code (CURLE_SSL_ISSUER_ERROR) is defined with the option, 47 which is returned if the setup of the SSL/TLS session has failed due to a 48 mismatch with the issuer of peer certificate (CURLOPT_PROXY_SSL_VERIFYPEER(3) 49 has to be set too for the check to fail). 50 51 The application does not have to keep the string around after setting this 52 option. 53 54 Using this option multiple times makes the last set string override the 55 previous ones. Set it to NULL to disable its use again. 56 57 # DEFAULT 58 59 NULL 60 61 # %PROTOCOLS% 62 63 # EXAMPLE 64 65 ~~~c 66 int main(void) 67 { 68 CURL *curl = curl_easy_init(); 69 if(curl) { 70 CURLcode res; 71 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/"); 72 /* using an HTTPS proxy */ 73 curl_easy_setopt(curl, CURLOPT_PROXY, "https://localhost:443"); 74 curl_easy_setopt(curl, CURLOPT_PROXY_ISSUERCERT, "/etc/certs/cacert.pem"); 75 res = curl_easy_perform(curl); 76 curl_easy_cleanup(curl); 77 } 78 } 79 ~~~ 80 81 # %AVAILABILITY% 82 83 # RETURN VALUE 84 85 curl_easy_setopt(3) returns a CURLcode indicating success or error. 86 87 CURLE_OK (0) means everything was OK, non-zero means an error occurred, see 88 libcurl-errors(3).