ProxyConf

A small command line tool to set proxy configuration on Windows.

Why does it exists

Using command-line only windows version (Core or Nano) behind a proxy can be problematic: some windows applications use IE settings but there is no good way to set them, other use WinHTTP settings that netsh winhttp can configure but it's not available on latest nano server images.

proxyconf aim to be a simple command line tool that can do this configuration and is suitable to use in containers (Docker).

Sample usage

FROM microsoft/nanoserver:1803

COPY proxyconf.exe .
RUN proxyconf set proxy 10.0.0.1:8080 "*.my-company;<local>"

Command line

• proxyconf show Show the current proxy configuration
• proxyconf set Set the proxy configuration. One of theses must be specified:
  • no-proxy No proxy should be used.
  • auto-detect Automatically detect settings. Windows will use the Web Proxy Autodiscovery Protocol or fallback to direct connection
  • proxy <ADDRESS:PORT> [BYPASS_LIST]
    • ADDRESS:PORT The proxy server and optional port to use.
    • BYPASS_LIST Optional list of addresses that bypass the proxy separated by semicolons (;). Use <local> to bypass all short name hosts. Default to <local> if not specified.
  • setup-script <URL> Use Proxy auto-config (PAC) from the specified URL.

Technical information

This tool set some specific keys in the registry, with the following format:

Internet explorer settings

They are stored in the registry key HKCU:SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Connections in the REG_BINARY DefaultConnectionSettings value.

The (undocumented) format is (With all values in little endian):

• version: u32 Seem to be a version number unconfirmed.
• counter: u32 An incremential counter used to detect changes.
• configuration_bits: u32 A bit field with the following bits:
  1. Always set
  2. Use manual proxy
  3. Use setup script
  4. Automatically detect settings
• proxy_address_len: u32 Length of the proxy address string.
• proxy_addres: Vec<u8> Proxy address (ASCII).
• bypass_list_len: u32 Length of the bypass list string.
• bypass_list: Vec<u8> Bypass list (ASCII).
• setup_script_len: u32 Length of the setup script url string.
• setup_script: Vec<u8> Setup script url (ASCII).