add first version of uefi client

.gitignore

@@ -19,3 +19,4 @@ Cargo.lock
 # Added by cargo
 
 /target
+build/

Cargo.toml

@@ -3,6 +3,8 @@ name = "http_boot_client"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
 [dependencies]
+log = "0.4.19"
+uefi = { version = "0.24.0", features = ["alloc"] }
+uefi-raw = "0.3.0"
+uefi-services = "0.21.0"

Makefile

@@ -0,0 +1,12 @@
+.PHONY: build
+
+build:
+	cargo build --target x86_64-unknown-uefi
+
+testvm:
+	cp target/x86_64-unknown-uefi/debug/http_boot_client.efi build/esp/efi/httpboot/httpboot.efi
+	qemu-system-x86_64 -enable-kvm \
+		-drive if=pflash,format=raw,readonly=on,file=build/OVMF_CODE.fd \
+		-drive if=pflash,format=raw,readonly=off,file=build/OVMF_VARS.fd \
+		-drive format=raw,file=fat:rw:build/esp \
+		-netdev user,id=n1 -device virtio-net-pci,netdev=n1

README.md

@@ -1,2 +1,16 @@
 # http-boot-client
 
+Commands to add the correct values to UEFI shell
+
+```
+# 0x2a corresponds to 42
+setvar -rt -nv -guid 638a24ce-a0ce-4908-8152-b2a4e8b2f29d HTTP_BOOT_MCAST_PORT =2a
+setvar -rt -nv -guid 638a24ce-a0ce-4908-8152-b2a4e8b2f29d HTTP_BOOT_MCAST_GROUP =ff0200000000000000000000abcd1234
+setvar -rt -nv -guid 638a24ce-a0ce-4908-8152-b2a4e8b2f29d HTTP_BOOT_UUID ="ffaf8813-fe27-4b1d-9d24-edb1baee9db9"
+```
+
+View current values
+
+```
+dmpstore -guid 638a24ce-a0ce-4908-8152-b2a4e8b2f29d
+```

rust-toolchain.toml

@@ -0,0 +1,2 @@
+[toolchain]
+targets = ["aarch64-unknown-uefi", "i686-unknown-uefi", "x86_64-unknown-uefi"]

src/config.rs

@@ -0,0 +1,71 @@
+use alloc::string::String;
+use log::{debug, info};
+use uefi::prelude::*;
+use uefi::proto::network::IpAddress;
+use uefi::CStr16;
+use uefi::{Error, Result};
+use uefi_raw::table::runtime::VariableVendor;
+use uefi_raw::{Guid, Status};
+
+extern crate alloc;
+
+const HTTP_BOOT_VENDOR: VariableVendor =
+    VariableVendor(Guid::parse_or_panic("638a24ce-a0ce-4908-8152-b2a4e8b2f29d"));
+
+pub struct Config {
+    pub multicast_group: IpAddress,
+    pub multicast_port: u16,
+    pub client_uuid: String,
+}
+
+fn get_var<'a>(
+    runtime_services: &RuntimeServices,
+    var_name: &'a CStr16,
+    res: &'a mut [u8],
+) -> Result<()> {
+    match runtime_services.get_variable(var_name, &HTTP_BOOT_VENDOR, res) {
+        Err(e) => Err(e),
+        Ok(_r) => Ok(()),
+    }
+}
+
+pub fn read_config(runtime_services: &RuntimeServices) -> Result<Config> {
+    info!("Reading EFI configuration from EFI vars");
+
+    let mut conf = Config {
+        multicast_group: IpAddress::new_v6([
+            0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+            0x00, 0x01,
+        ]),
+        multicast_port: 42,
+        client_uuid: String::from("24609104-7ec6-423f-b57f-632b99b7566a"),
+    };
+
+    let mut port_buf: [u8; 2] = [0; 2]; // port is 16 bytes encoded
+    get_var(
+        runtime_services,
+        cstr16!("HTTP_BOOT_MCAST_PORT"),
+        &mut port_buf,
+    )?;
+    conf.multicast_port = u16::from_ne_bytes(port_buf);
+    debug!("Got port {}", conf.multicast_port);
+
+    let mut group_buf: [u8; 16] = [0; 16]; // at most ipv6 is 16 bytes
+    get_var(
+        runtime_services,
+        cstr16!("HTTP_BOOT_MCAST_GROUP"),
+        &mut group_buf,
+    )?;
+    conf.multicast_group = IpAddress::new_v6(group_buf);
+    debug!("Got group {:?}", conf.multicast_group);
+
+    let mut uid_buf: [u8; 36] = [0; 36]; // uuid is 36 bytes
+    get_var(runtime_services, cstr16!("HTTP_BOOT_UUID"), &mut uid_buf)?;
+    conf.client_uuid = match String::from_utf8(uid_buf.to_vec()) {
+        Err(_e) => return Err(Error::from(Status::INVALID_PARAMETER)),
+        Ok(s) => s,
+    };
+    debug!("Got uuid {:?}", conf.client_uuid);
+
+    Ok(conf)
+}

src/main.rs

@@ -1,3 +1,44 @@
-fn main() {
-    println!("Hello, world!");
+#![no_main]
+#![no_std]
+
+pub mod config;
+pub mod multicast;
+
+use log::info;
+use uefi::fs::PathBuf;
+use uefi::prelude::*;
+use uefi::table::boot::LoadImageSource;
+use uefi::{Error, Result, Status};
+
+fn load_efi_app_from_path(boot_services: &BootServices, app_path: PathBuf) -> Result {
+    let mut fs_handler = boot_services.get_image_file_system(boot_services.image_handle())?;
+    let app_content = match fs_handler.read(app_path) {
+        Err(_e) => return Err(Error::from(Status::PROTOCOL_ERROR)),
+        Ok(x) => x,
+    };
+    let image_source = LoadImageSource::FromBuffer {
+        buffer: &app_content,
+        file_path: None,
+    };
+    let img_handler = boot_services.load_image(boot_services.image_handle(), image_source)?;
+    boot_services.start_image(img_handler)
+}
+
+#[entry]
+fn main(_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
+    info!("init service");
+
+    uefi_services::init(&mut system_table).unwrap();
+
+    info!("init boot services");
+    let boot_services = system_table.boot_services();
+
+    info!("init runtime services");
+    let runtime_services = system_table.runtime_services();
+
+    let conf = config::read_config(runtime_services).unwrap();
+    let app_path = multicast::send_mcast(boot_services, &conf).unwrap();
+    load_efi_app_from_path(boot_services, app_path).unwrap();
+
+    Status::SUCCESS
 }

src/multicast.rs

@@ -0,0 +1,145 @@
+use alloc::string::String;
+use log::{debug, error, info};
+use uefi::prelude::*;
+use uefi::proto::network::pxe::{BaseCode, UdpOpFlags};
+use uefi::proto::network::IpAddress;
+use uefi::table::boot::{ScopedProtocol, SearchType};
+use uefi::{Error, Identify, Result};
+extern crate alloc;
+use crate::config::Config;
+use uefi::data_types::CStr16;
+use uefi::fs::{Path, PathBuf};
+
+fn split_arg(raw_val: &str) -> Option<(&str, &str)> {
+    let mut splitted = raw_val.split("=");
+    let arg_name = match splitted.next() {
+        None => return None,
+        Some(v) => v,
+    };
+    let arg_value = match splitted.next() {
+        None => return None,
+        Some(v) => v,
+    };
+    return Some((arg_name, arg_value));
+}
+
+fn get_boot_path<'a>(msg: String) -> Result<PathBuf, &'a str> {
+    debug!("Splitting message");
+
+    // a message has the following format: "ACTION arg1=val1,arg2=val2"
+    let mut splitted_msg_iter = msg.split_ascii_whitespace();
+
+    debug!("Checking if message is a valid BOOT_ACCEPT message");
+    match splitted_msg_iter.next() {
+        None => return Err(Error::new(Status::UNSUPPORTED, "empty message")),
+        Some(action) => match action {
+            "BOOT_ACCEPT" => (),
+            "BOOT_DENY" => return Err(Error::new(Status::UNSUPPORTED, "boot refused")),
+            _ => return Err(Error::new(Status::UNSUPPORTED, "unexpected action")),
+        },
+    }
+
+    debug!("Parsing message arguments");
+    match splitted_msg_iter.next() {
+        None => return Err(Error::new(Status::UNSUPPORTED, "empty list of arguments")),
+        Some(args_list) => {
+            // split all the arguments in a comma separated list
+            for arg in args_list.split(",") {
+                match split_arg(arg) {
+                    None => debug!("unexpected format for argument {}", arg),
+                    Some((arg_name, arg_value)) => match arg_name {
+                        "id" => debug!("found id {}", arg_value),
+                        "efi_app" => {
+                            debug!("found efi app {}", arg_value);
+                            let mut buf = [0; 128];
+                            let path_raw = CStr16::from_str_with_buf(arg_value, &mut buf)
+                                .expect("invalid str format");
+                            let p = Path::new(path_raw);
+                            let mut res = PathBuf::new();
+                            res.push(p);
+                            return Ok(res);
+                        }
+                        _ => debug!("unexpected argument {} with value {}", arg_name, arg_value),
+                    },
+                }
+            }
+        }
+    }
+    Err(Error::new(Status::UNSUPPORTED, "no efi app defined"))
+}
+
+fn read_mcast_response<'a>(base_client: &mut ScopedProtocol<'_, BaseCode>) -> Result<PathBuf> {
+    let mut buf: [u8; 200] = [0; 200];
+
+    let n = base_client
+        .udp_read(
+            UdpOpFlags::ANY_DEST_IP
+                | UdpOpFlags::ANY_DEST_PORT
+                | UdpOpFlags::ANY_SRC_IP
+                | UdpOpFlags::ANY_SRC_PORT,
+            None,
+            None,
+            None,
+            None,
+            None,
+            &mut buf,
+        )
+        .unwrap();
+
+    info!("Read {} bytes", n);
+    let received_msg = String::from_utf8(buf[..n].to_vec()).unwrap();
+    info!("Received message {}", received_msg);
+    match get_boot_path(received_msg) {
+        Ok(r) => Ok(r),
+        Err(e) => {
+            error!("failed to get boot path: {}", e.data());
+            Err(e.to_err_without_payload())
+        }
+    }
+}
+
+pub fn send_mcast<'a>(boot_service: &BootServices, conf: &Config) -> Result<PathBuf> {
+    debug!("Initializing base bootservice client handle");
+    let base_client_handle = *boot_service
+        .locate_handle_buffer(SearchType::ByProtocol(&BaseCode::GUID))?
+        .first()
+        .expect("DevicePathToText is missing");
+
+    let mut base_client = boot_service.open_protocol_exclusive::<BaseCode>(base_client_handle)?;
+
+    debug!("Initializing source IP address");
+    let src_bytes: [u8; 16] = [
+        0x20, 0x01, 0x0d, 0xb8, 0x00, 0x00, 0x00, 0x00, 0x02, 0x16, 0x3e, 0xff, 0xfe, 0xc2, 0x16,
+        0xb7,
+    ];
+    let src_address: IpAddress = IpAddress::new_v6(src_bytes);
+
+    let mut req_msg = String::from("BOOT_REQUEST id=");
+    req_msg.push_str(&conf.client_uuid);
+
+    info!("Starting PXE client");
+    debug!("Starting PXE client");
+    base_client.start(true)?;
+
+    debug!("Setting IP address for PXE client");
+    base_client.set_station_ip(Some(&src_address), None)?;
+
+    info!("Sending UDP multicast message");
+    base_client.udp_write(
+        UdpOpFlags::MAY_FRAGMENT,
+        &conf.multicast_group,
+        conf.multicast_port,
+        None,
+        Some(&src_address),
+        None,
+        None,
+        req_msg.as_bytes(),
+    )?;
+    let res = read_mcast_response(&mut base_client);
+
+    info!("Stopping PXE client");
+    base_client.stop()?;
+
+    info!("PXE client successfully executed");
+    res
+}