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curl/docs/libcurl/opts/CURLOPT_PROXY_SSLCERT.3

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proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.\" **************************************************************************
.\" * _ _ ____ _
.\" * Project ___| | | | _ \| |
.\" * / __| | | | |_) | |
.\" * | (__| |_| | _ <| |___
.\" * \___|\___/|_| \_\_____|
.\" *
.\" * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.\" *
.\" * This software is licensed as described in the file COPYING, which
.\" * you should have received as part of this distribution. The terms
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.\" * are also available at https://curl.se/docs/copyright.html.
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.\" *
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
.\" * copies of the Software, and permit persons to whom the Software is
.\" * furnished to do so, under the terms of the COPYING file.
.\" *
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
.\" * KIND, either express or implied.
.\" *
.\" **************************************************************************
.\"
.TH CURLOPT_PROXY_SSLCERT 3 "16 Nov 2016" "libcurl 7.52.0" "curl_easy_setopt options"
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.SH NAME
CURLOPT_PROXY_SSLCERT \- set SSL proxy client certificate
.SH SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_SSLCERT, char *cert);
.SH DESCRIPTION
This option is for connecting to an HTTPS proxy, not an HTTPS server.
Pass a pointer to a null-terminated string as parameter. The string should be
the file name of your client certificate used to connect to the HTTPS proxy.
The default format is "P12" on Secure Transport and "PEM" on other engines,
and can be changed with \fICURLOPT_PROXY_SSLCERTTYPE(3)\fP.
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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With NSS or Secure Transport, this can also be the nickname of the certificate
you wish to authenticate with as it is named in the security database. If you
want to use a file from the current directory, please precede it with "./"
prefix, in order to avoid confusion with a nickname.
When using a client certificate, you most likely also need to provide a
private key with \fICURLOPT_PROXY_SSLKEY(3)\fP.
The application does not have to keep the string around after setting this
option.
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.SH DEFAULT
NULL
.SH PROTOCOLS
Used with HTTPS proxy
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_PROXY, "https://proxy");
curl_easy_setopt(curl, CURLOPT_PROXY_SSLCERT, "client.pem");
curl_easy_setopt(curl, CURLOPT_PROXY_SSLKEY, "key.pem");
curl_easy_setopt(curl, CURLOPT_PROXY_KEYPASSWD, "s3cret");
ret = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
.fi
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.SH AVAILABILITY
Added in 7.52.0
proxy: Support HTTPS proxy and SOCKS+HTTP(s) * HTTPS proxies: An HTTPS proxy receives all transactions over an SSL/TLS connection. Once a secure connection with the proxy is established, the user agent uses the proxy as usual, including sending CONNECT requests to instruct the proxy to establish a [usually secure] TCP tunnel with an origin server. HTTPS proxies protect nearly all aspects of user-proxy communications as opposed to HTTP proxies that receive all requests (including CONNECT requests) in vulnerable clear text. With HTTPS proxies, it is possible to have two concurrent _nested_ SSL/TLS sessions: the "outer" one between the user agent and the proxy and the "inner" one between the user agent and the origin server (through the proxy). This change adds supports for such nested sessions as well. A secure connection with a proxy requires its own set of the usual SSL options (their actual descriptions differ and need polishing, see TODO): --proxy-cacert FILE CA certificate to verify peer against --proxy-capath DIR CA directory to verify peer against --proxy-cert CERT[:PASSWD] Client certificate file and password --proxy-cert-type TYPE Certificate file type (DER/PEM/ENG) --proxy-ciphers LIST SSL ciphers to use --proxy-crlfile FILE Get a CRL list in PEM format from the file --proxy-insecure Allow connections to proxies with bad certs --proxy-key KEY Private key file name --proxy-key-type TYPE Private key file type (DER/PEM/ENG) --proxy-pass PASS Pass phrase for the private key --proxy-ssl-allow-beast Allow security flaw to improve interop --proxy-sslv2 Use SSLv2 --proxy-sslv3 Use SSLv3 --proxy-tlsv1 Use TLSv1 --proxy-tlsuser USER TLS username --proxy-tlspassword STRING TLS password --proxy-tlsauthtype STRING TLS authentication type (default SRP) All --proxy-foo options are independent from their --foo counterparts, except --proxy-crlfile which defaults to --crlfile and --proxy-capath which defaults to --capath. Curl now also supports %{proxy_ssl_verify_result} --write-out variable, similar to the existing %{ssl_verify_result} variable. Supported backends: OpenSSL, GnuTLS, and NSS. * A SOCKS proxy + HTTP/HTTPS proxy combination: If both --socks* and --proxy options are given, Curl first connects to the SOCKS proxy and then connects (through SOCKS) to the HTTP or HTTPS proxy. TODO: Update documentation for the new APIs and --proxy-* options. Look for "Added in 7.XXX" marks.
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.SH RETURN VALUE
Returns CURLE_OK if TLS enabled, CURLE_UNKNOWN_OPTION if not, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.
.SH "SEE ALSO"
.BR CURLOPT_PROXY_SSLCERTTYPE "(3), " CURLOPT_PROXY_SSLKEY "(3), "
.BR CURLOPT_SSLCERT "(3), "