.\" generated by cd2nroff 0.1 from CURLOPT_SSLCERT.md
.TH CURLOPT_SSLCERT 3 "2024-11-18" libcurl
.SH NAME
CURLOPT_SSLCERT \- SSL client certificate
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLCERT, char *cert);
.fi
.SH DESCRIPTION
Pass a pointer to a null\-terminated string as parameter. The string should be
the filename of your client certificate. The default format is \fIP12\fP on Secure
Transport and \fIPEM\fP on other engines, and can be changed with
\fICURLOPT_SSLCERTTYPE(3)\fP.

With 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 \fI./\fP prefix,
in order to avoid confusion with a nickname.

(Schannel only) Client certificates can be specified by a path expression to a
certificate store. (You can import \fIPFX\fP to a store first). You can use
\&"<store location>\\<store name>\\<thumbprint>" to refer to a certificate
in the system certificates store, for example,
\fB"CurrentUser\\MY\\934a7ac6f8a5d579285a74fa"\fP. The thumbprint is usually a
SHA\-1 hex string which you can see in certificate details. Following store
locations are supported: \fBCurrentUser\fP, \fBLocalMachine\fP,
\fBCurrentService\fP, \fBServices\fP, \fBCurrentUserGroupPolicy\fP,
\fBLocalMachineGroupPolicy\fP, \fBLocalMachineEnterprise\fP. Schannel also support
P12 certificate file, with the string \fIP12\fP specified with
\fICURLOPT_SSLCERTTYPE(3)\fP.

When using a client certificate, you most likely also need to provide a
private key with \fICURLOPT_SSLKEY(3)\fP.

The application does not have to keep the string around after setting this
option.
.SH DEFAULT
NULL
.SH PROTOCOLS
This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.

This option works only with the following TLS backends:
GnuTLS, OpenSSL, Schannel, Secure Transport, mbedTLS and wolfSSL
.SH EXAMPLE
.nf
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    curl_easy_setopt(curl, CURLOPT_SSLCERT, "client.pem");
    curl_easy_setopt(curl, CURLOPT_SSLKEY, "key.pem");
    curl_easy_setopt(curl, CURLOPT_KEYPASSWD, "s3cret");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.1
.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_KEYPASSWD (3),
.BR CURLOPT_SSLCERTTYPE (3),
.BR CURLOPT_SSLKEY (3)