From 1b0ee15bf8cd72dc82c4ff20f638ac375007aea6 Mon Sep 17 00:00:00 2001
From: Jesper Brynolf <jesper.brynolf@gmail.com>
Date: Fri, 13 Sep 2024 22:02:11 +0200
Subject: [PATCH] Adds a TBS TctiNameConf.

When #477 got merged it became possible to build
using a path to the ```tpm2-tss``` installation
instead of depending on ```pkg-config```.

This made it possible to build under Windows. To
further increase the support for the windows
platform this commit moves the option for TBS
TCTI that is being introduced in #523 into a
separate commit.

This commit also updates the documentation
regarding building using an installation
folder.

Co-author: Thomas Thomas Epperson <thomas.epperson@gmail.com>
Signed-off-by: Jesper Brynolf <jesper.brynolf@gmail.com>
---
 tss-esapi-sys/README.md   | 21 +++++++++++++++++++++
 tss-esapi/src/tcti_ldr.rs | 15 +++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/tss-esapi-sys/README.md b/tss-esapi-sys/README.md
index 6f87584f..d4eeddc1 100644
--- a/tss-esapi-sys/README.md
+++ b/tss-esapi-sys/README.md
@@ -62,4 +62,25 @@ wrapper script around `pkg-config` can be seen
 Be advised that in some cases the linker used might need to be set manually in
 `.cargo/config`.
 
+## Locally built tpm2-tss
+It is now possible to specify an installation path when building the crate. This will
+make the build process trying to find all the libraries and header files it needs from
+installation path instead of using `pkg-config`.
+
+The `TPM2_TSS_PATH` environment variable name is used to specify the path to the installation.
+The installation is required to have a specific layout.
+
+```bash
+├── <'Installation folder'>
+|   ├── bin (optional)
+|   |   ├── tss2-*.dll (Windows)
+│   ├── include
+│   │   ├── tss2
+│   │       ├── tss2_*.h
+│   ├── lib
+│   │   ├── tss2-*.lib (Windows)
+|   |   ├── tss2-*.so  (Nix)
+│   │   ├── tss2-*.pdb (Windows)
+│   └── VERSION
+```
 *Copyright 2021 Contributors to the Parsec project.*
diff --git a/tss-esapi/src/tcti_ldr.rs b/tss-esapi/src/tcti_ldr.rs
index f564baf8..a59f6ea4 100644
--- a/tss-esapi/src/tcti_ldr.rs
+++ b/tss-esapi/src/tcti_ldr.rs
@@ -21,6 +21,7 @@ const DEVICE: &str = "device";
 const MSSIM: &str = "mssim";
 const SWTPM: &str = "swtpm";
 const TABRMD: &str = "tabrmd";
+const TBS: &str = "tbs";
 
 /// TCTI Context created via a TCTI Loader Library.
 /// Wrapper around the TSS2_TCTI_CONTEXT structure.
@@ -143,6 +144,10 @@ pub enum TctiNameConf {
     ///
     /// For more information about configuration, see [this page](https://www.mankier.com/3/Tss2_Tcti_Tabrmd_Init)
     Tabrmd(TabrmdConfig),
+    /// Connect to the tpm using the Trusted Platform Module (TPM) Base Services (TBS) on Windows.
+    ///
+    /// For more information about TBS, see [this page](https://learn.microsoft.com/en-us/windows/win32/tbs/about-tbs)
+    Tbs,
 }
 
 impl TctiNameConf {
@@ -174,6 +179,7 @@ impl TryFrom<TctiNameConf> for CString {
             TctiNameConf::Mssim(..) => MSSIM,
             TctiNameConf::Swtpm(..) => SWTPM,
             TctiNameConf::Tabrmd(..) => TABRMD,
+            TctiNameConf::Tbs => TBS,
         };
 
         let tcti_conf = match tcti {
@@ -204,6 +210,7 @@ impl TryFrom<TctiNameConf> for CString {
             TctiNameConf::Tabrmd(config) => {
                 format!("bus_name={},bus_type={}", config.bus_name, config.bus_type)
             }
+            TctiNameConf::Tbs => String::new(),
         };
 
         if tcti_conf.is_empty() {
@@ -247,6 +254,10 @@ impl FromStr for TctiNameConf {
             )?));
         }
 
+        if config_str.trim() == TBS {
+            return Ok(TctiNameConf::Tbs);
+        }
+
         Err(Error::WrapperError(WrapperErrorKind::InvalidParam))
     }
 }
@@ -327,6 +338,10 @@ fn validate_from_str_tcti() {
 
     let tcti = TctiNameConf::from_str("tabrmd").unwrap();
     assert_eq!(tcti, TctiNameConf::Tabrmd(Default::default()));
+
+    let tcti_tbs = TctiNameConf::from_str("tbs")
+        .expect("It should be possible to convert the string 'tbs' into a TctiNameConf object.");
+    assert!(tcti_tbs, TctiNameConf::Tbs);
 }
 
 /// Configuration for a Device TCTI context