CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256 - SHA256 hash of SSH server public key

Added in curl 7.80.0

NULL

Pass a char pointer pointing to a string containing a Base64-encoded SHA256 hash of the remote host's public key. The transfer fails if the given hash does not match the hash the remote host provides. The application does not have to keep the string around after setting this option. Using this option multiple times makes the last set string override the previous ones. Set it to NULL to disable its use again.

int main(void) { CURL *curl = curl_easy_init(); if(curl) { CURLcode res; curl_easy_setopt(curl, CURLOPT_URL, "sftp://example.com/file"); curl_easy_setopt(curl, CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256, "NDVkMTQxMGQ1ODdmMjQ3MjczYjAyOTY5MmRkMjVmNDQ="); res = curl_easy_perform(curl); curl_easy_cleanup(curl); } }

CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256 - SHA256 hash of SSH server public key

Requires the libssh2 backend.

This functionality affects scp and sftp

curl_easy_setopt(3) returns a CURLcode indicating success or error. CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).

CURLOPT_SSH_AUTH_TYPES(3), CURLOPT_SSH_HOST_PUBLIC_KEY_MD5(3), CURLOPT_SSH_PUBLIC_KEYFILE(3) libcurl 2025-06-16 CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256(3)

#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256, char *sha256);