.\" generated by cd2nroff 0.1 from CURLOPT_PROXY_SSLKEY_BLOB.md
.TH CURLOPT_PROXY_SSLKEY_BLOB 3 "2026-10-31" libcurl
.SH NAME
CURLOPT_PROXY_SSLKEY_BLOB \- private key for proxy cert from memory blob
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_SSLKEY_BLOB,
                          struct curl_blob *blob);
.fi
.SH DESCRIPTION
Pass a pointer to a curl_blob structure that contains information (pointer and
size) about the private key for connecting to the HTTPS proxy. Compatible with
OpenSSL and Rustls. The format (like "PEM") must be specified with
\fICURLOPT_PROXY_SSLKEYTYPE(3)\fP.

If the blob is initialized with the flags member of struct curl_blob set to
CURL_BLOB_COPY, the application does not have to keep the buffer around after
setting this.
.SH DEFAULT
NULL
.SH PROTOCOLS
This functionality affects  all TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc. only

This option works only with the following TLS backends:
OpenSSL and Rustls
.SH EXAMPLE
.nf

extern char *certificateData; /* point to data */
extern size_t filesize; /* size of data */

extern char *privateKeyData; /* point to data */
extern size_t privateKeySize; /* size */

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    struct curl_blob blob;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    curl_easy_setopt(curl, CURLOPT_PROXY, "https://proxy.example");
    blob.data = certificateData;
    blob.len = filesize;
    blob.flags = CURL_BLOB_COPY;
    curl_easy_setopt(curl, CURLOPT_PROXY_SSLCERT_BLOB, &blob);
    curl_easy_setopt(curl, CURLOPT_PROXY_SSLCERTTYPE, "PEM");

    blob.data = privateKeyData;
    blob.len = privateKeySize;
    curl_easy_setopt(curl, CURLOPT_PROXY_SSLKEY_BLOB, &blob);
    curl_easy_setopt(curl, CURLOPT_PROXY_KEYPASSWD, "s3cret");
    result = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.71.0
.SH RETURN VALUE
\fIcurl_easy_setopt(3)\fP returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non\-zero means an error occurred, see
\fIlibcurl\-errors(3)\fP.
.SH SEE ALSO
.BR CURLOPT_SSLKEY (3),
.BR CURLOPT_SSLKEYTYPE (3),
.BR CURLOPT_SSLKEY_BLOB (3)