CURLOPT_SOCKS5_GSSAPI_NEC(3)

CURLOPT_SOCKS5_GSSAPI_NEC3

Socks proxy gssapi negotiation protection

Usage

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SOCKS5_GSSAPI_NEC, long nec);

Overview

Pass a long set to 1 to enable or 0 to disable. As part of the GSSAPI negotiation a protection mode is negotiated. The RFC 1961 says in section 4.3/4.4 it should be protected, but the NEC reference implementation does not. If enabled, this option allows the unprotected exchange of the protection mode negotiation.

Default

?

Protocols

This functionality affects all supported protocols

Examples

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    curl_easy_setopt(curl, CURLOPT_PROXY, "socks5://proxy");
    curl_easy_setopt(curl, CURLOPT_SOCKS5_GSSAPI_NEC, 1L);
    result = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

Return value

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).

Releases

7 releases since Debian 8 (Jessie); the text changed 6 times.

  1. 8
  2. 9
  3. 10
  4. 11
  5. 12
  6. 13
  7. Arch

Availability

Added in curl 7.19.4

From curl 8.23.0-1 in Arch Linux 2026-11-01. Parsed by carta from the page's man source.