virtfw-igvm-tools 0.1.1

//!
//! wrap classic native firmware image as igvm
//!
use log::{error, info};
use std::cmp::min;
use std::env;
use std::fs;
use std::process::ExitCode;

use igvm::{
    Arch, IgvmDirectiveHeader, IgvmFile, IgvmInitializationHeader, IgvmPlatformHeader, IgvmRevision,
};
use igvm_defs::{
    IgvmPageDataFlags, IgvmPageDataType, IgvmPlatformType, IGVM_VHS_SUPPORTED_PLATFORM,
    PAGE_SIZE_4K,
};

pub const NATIVE_COMPAT: u32 = 1u32 << 0;

struct Builder {
    revision: IgvmRevision,
    platforms: Vec<IgvmPlatformHeader>,
    initializations: Vec<IgvmInitializationHeader>,
    directives: Vec<IgvmDirectiveHeader>,
}

impl Builder {
    fn new() -> Builder {
        let revision = IgvmRevision::V2 {
            arch: Arch::X64,
            page_size: PAGE_SIZE_4K.try_into().unwrap(),
        };
        let platforms = Vec::new();
        let initializations = Vec::new();
        let directives = Vec::new();
        Builder {
            revision,
            platforms,
            initializations,
            directives,
        }
    }

    fn add_native_platform(&mut self) -> &mut Builder {
        let native = IgvmPlatformHeader::SupportedPlatform(IGVM_VHS_SUPPORTED_PLATFORM {
            compatibility_mask: NATIVE_COMPAT,
            highest_vtl: 2,
            platform_type: IgvmPlatformType::NATIVE,
            platform_version: 1,
            shared_gpa_boundary: 0,
        });
        self.platforms.push(native);
        self
    }

    fn add_pages(&mut self, base: usize, data: &[u8]) -> &mut Builder {
        let pages = data.len() / PAGE_SIZE_4K as usize;
        for pg in 0..pages {
            let start = pg * PAGE_SIZE_4K as usize;
            let end = start + PAGE_SIZE_4K as usize;
            let page = IgvmDirectiveHeader::PageData {
                gpa: (base + start) as u64,
                compatibility_mask: NATIVE_COMPAT,
                flags: IgvmPageDataFlags::new(),
                data_type: IgvmPageDataType::NORMAL,
                data: data[start..end].to_vec(),
            };
            self.directives.push(page);
        }
        self
    }

    fn add_firmware(&mut self, firmware: &[u8]) -> &mut Builder {
        // all below 4GB
        let fwbase = (1u64 << 32) as usize - firmware.len();
        self.add_pages(fwbase, firmware);
        // 128k below 1MB
        let lowsize = min(128 * 1024, firmware.len());
        let lowbase = (1u64 << 20) as usize - lowsize;
        let offset = firmware.len() - lowsize;
        self.add_pages(lowbase, &firmware[offset..]);
        self
    }

    fn finalize(&self) -> Result<IgvmFile, igvm::Error> {
        IgvmFile::new(
            self.revision,
            self.platforms.clone(),
            self.initializations.clone(),
            self.directives.clone(),
        )
    }
}

fn parse_args() -> Option<getopts::Matches> {
    let args: Vec<String> = env::args().collect();
    let mut opts = getopts::Options::new();
    opts.optflag("h", "help", "print this help text");

    opts.optopt("i", "input", "input bios image", "BIOS");
    opts.optopt("o", "output", "output igvm image", "IGVM");

    let cfg_res = opts.parse(&args[1..]);
    let Ok(cfg) = cfg_res else {
        println!("{:?}", cfg_res.err());
        return None;
    };
    if cfg.opt_present("help") {
        print!(
            "{}",
            opts.usage("igvm-wrap -- wrap classic native firmware image as igvm")
        );
        return None;
    };

    Some(cfg)
}

fn main() -> ExitCode {
    let Some(cfg) = parse_args() else {
        return ExitCode::from(1);
    };

    stderrlog::new()
        .module(module_path!())
        .verbosity(stderrlog::LogLevelNum::Debug)
        .init()
        .unwrap();

    if let Some(infile) = cfg.opt_str("input") {
        info!("reading {}", &infile);

        let firmware_res = fs::read(&infile);
        if let Err(e) = firmware_res {
            error!("read {}: {}", &infile, e);
            return ExitCode::from(1);
        }
        let firmware = firmware_res.unwrap();

        let mut builder = Builder::new();
        builder.add_native_platform().add_firmware(&firmware);
        let igvm_res = builder.finalize();
        if let Err(e) = igvm_res {
            error!("build igvm: {}", e);
            return ExitCode::from(1);
        }

        if let Some(outfile) = cfg.opt_str("output") {
            let mut blob = Vec::new();
            let res = igvm_res.unwrap().serialize(&mut blob);
            if let Err(e) = res {
                error!("serialize igvm: {}", e);
                return ExitCode::from(1);
            }

            info!("writing {}", &outfile);
            let res = fs::write(&outfile, blob);
            if let Err(e) = res {
                error!("write {}: {}", &outfile, e);
                return ExitCode::from(1);
            }
        } else {
            info!("igvm ok");
        }
    }

    ExitCode::from(0)
}