.\" generated by cd2nroff 0.1 from CURLOPT_SSH_HOST_PUBLIC_KEY_MD5.md
.TH CURLOPT_SSH_HOST_PUBLIC_KEY_MD5 3 "2025-10-19" libcurl
.SH NAME
CURLOPT_SSH_HOST_PUBLIC_KEY_MD5 \- MD5 checksum of SSH server public key
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSH_HOST_PUBLIC_KEY_MD5,
                          char *md5);
.fi
.SH DESCRIPTION
Pass a char pointer pointing to a string containing 32 hexadecimal digits. The
string should be the 128 bit MD5 checksum of the remote host\(aqs public key, and
libcurl aborts the connection to the host unless the MD5 checksum match.

MD5 is a weak algorithm. We strongly recommend using
\fICURLOPT_SSH_HOST_PUBLIC_KEY_SHA256(3)\fP instead.

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.
.SH DEFAULT
NULL
.SH PROTOCOLS
This functionality affects scp and sftp
.SH EXAMPLE
.nf
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_MD5,
                     "afe17cd62a0f3b61f1ab9cb22ba269a7");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.17.1
.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_SSH_AUTH_TYPES (3),
.BR CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256 (3),
.BR CURLOPT_SSH_KNOWNHOSTS (3),
.BR CURLOPT_SSH_PUBLIC_KEYFILE (3)