curl/docs/libcurl/opts/CURLOPT_SSLKEY_BLOB.md

---

c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Title: CURLOPT_SSLKEY_BLOB Section: 3 Source: libcurl See-also:

• CURLOPT_SSLKEY (3)
• CURLOPT_SSLKEYTYPE (3) Protocol:
• TLS TLS-backend:
• OpenSSL
• wolfSSL Added-in: 7.71.0 ---

NAME

CURLOPT_SSLKEY_BLOB - private key for client cert from memory blob

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLKEY_BLOB,
                          struct curl_blob *blob);

DESCRIPTION

Pass a pointer to a curl_blob structure, which contains information (pointer and size) for a private key. Compatible with OpenSSL. The format (like "PEM") must be specified with CURLOPT_SSLKEYTYPE(3).

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.

This option is an alternative to CURLOPT_SSLKEY(3) which instead expects a filename as input.

DEFAULT

NULL

%PROTOCOLS%

EXAMPLE

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

extern char *privateKeyData; /* point to key */
extern size_t privateKeySize; /* size of key */

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

    blob.data = privateKeyData;
    blob.len = privateKeySize;
    curl_easy_setopt(curl, CURLOPT_SSLKEY_BLOB, &blob);
    curl_easy_setopt(curl, CURLOPT_KEYPASSWD, "s3cret");
    curl_easy_setopt(curl, CURLOPT_SSLKEYTYPE, "PEM");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

%AVAILABILITY%

RETURN VALUE

Returns CURLE_OK if TLS enabled, CURLE_UNKNOWN_OPTION if not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.