Tool Command Language (TCL) Transport Layer Security (TLS) Extension Intro ===== This package provides an extension which implements Secure Socket Layer (SSL) and Transport Layer Security (TLS) encryption over Transmission Control Protocol (TCP) network communication channels utilizing the OpenSSL library. Description =========== This extension works by creating a layered TCL Channel on top of an existing bi-directional channel created by the TLS socket command. All existing socket functionality is supported in addition to several new options. Both client and server modes are supported. Documentation ============= See the doc directory for the full usage documentation. Compatibility ============= TCL --- This package requires TCL 8.5 or later. It will also work with TCL 9, but it is not binary compatible between major TCL versions. This means if this extension is built with TCL 8.x it will not load into TCL 9 or vice versa. It is best to compile both separately then install them with the compatible TCL versions. OpenSSL ------- This package is compatible with OpenSSL v1.1.1 or later, though 3.2 or later is preferred. See http://www.openssl.org/. Please note that there are a few API incompatibilities between OpenSSL 1.1.1 and 3.x, so if this extension is built against OpenSSL 1.1.1 it is not binary compatible with OpenSSL 3.x or vice versa. TCLTLS ------ There were several changes made in the callback command arguments between versions 1.7 and 2.0. See doc/tls.html for what changed and library/tls.tcl for example handler functions that are backwards compatible. Installation ============ This package uses the TCL Extension Architecture (TEA) to build and install on any supported Unix, Mac, or MS Windows system. It depends on the OpenSSL libraries being available prior to building the TCLTLS extension. UNIX and Linux -------------- The standard TEA config, make, and install process is supported. $ cd tcltls $ ./configure --enable-64bit $ make $ make test $ make install The supported configure options include all of the standard TEA configure script options, plus: --disable-tls1 disable TLS1 protocol --disable-tls1_1 disable TLS1.1 protocol --disable-tls1_2 disable TLS1.2 protocol --disable-tls1_3 disable TLS1.3 protocol --enable-debug enable debugging mode and output more status --enable-ssl-fastpath enable using the underlying file descriptor for talking directly to the SSL library --enable-hardening enable hardening attempts --enable-static-ssl enable static linking to the SSL library If either TCL or OpenSSL are installed in non-standard locations, the following configure options are available. For all options, see ./configure --help. --with-tcl= path to where tclCondig.sh file resides --with-tclinclude= directory containing the public Tcl header files --with-openssl-dir= path to root directory of OpenSSL installation --with-openssl-includedir= path to include directory of OpenSSL installation --with-openssl-libdir= path to lib directory of OpenSSL installation --with-openssl-pkgconfig= path to root directory of OpenSSL pkg-config directory MacOS ----- The standard TEA installation process is supported. Use the --with-tcl option to set the TCL path if the ActiveState or other non-Apple version of TCL is to be used. $ cd tcltls $ ./configure --with-tcl=/Library/Frameworks/Tcl.framework/ $ make $ make test $ make install Windows ------- If installing with MinGW, use the TEA build process. If using MS Visual C (MSVC), see win/README.txt for the build and installation instructions. Certificate Validation ---------------------- If OpenSSL is not installed on the system, the Certificate Authority (CA) provided certificates must be downloaded and installed with the software. These are used for certificate validation. The CURL team makes them available at https://curl.se/docs/caextract.html. Look for the cacert.pem file. Copyrights ========== Original TLS Copyright (C) 1997-2000 Matt Newman TLS 1.4.1 Copyright (C) 2000 Ajuba Solutions TLS 1.6 Copyright (C) 2008 ActiveState Software Inc. TLS 1.7 Copyright (C) 2016 Matt Newman, Ajuba Solutions, ActiveState Software Inc, Roy Keene TLS 1.8-2.0 Copyright (C) 2023-2024 Brian O'Hagan Acknowledgments =============== Non-exclusive credits for TLS are: Original work: Matt Newman @ Novadigm Updates: Jeff Hobbs @ ActiveState Tcl Channel mechanism: Andreas Kupries Impetus/Related work: tclSSL (Colin McCormack, Shared Technology) SSLtcl (Peter Antman) License ======= This code is licensed under the same terms as the Tcl Core.