add ShortId TBF header

README.md

@@ -31,6 +31,7 @@ Options:
       --write_id <write_id>                            A storage ID used for writing data
       --read_ids <read_ids>...                         Storage IDs that this app is allowed to read
       --access_ids <access_ids>...                     Storage IDs that this app is allowed to write
+      --short-id <short-id>                            ShortId to request in the app's header
       --kernel-major <kernel-major-version>            The kernel version that the app requires
       --kernel-minor <kernel-minor-version>            The minimum kernel minor version that the app requires
       --supported-boards <supported-boards>            comma separated list of boards this app is compatible with

src/cmdline.rs

@@ -157,6 +157,14 @@ pub struct Opt {
     )]
     pub access_ids: Option<Vec<u32>>,
 
+    #[arg(
+        long = "short-id",
+        id = "short-id",
+        help = "ShortId to request in the app's header",
+        value_parser=clap_num::maybe_hex::<u32>,
+    )]
+    pub short_id: Option<u32>,
+
     #[arg(
         long = "kernel-major",
         id = "kernel-major-version",

src/convert.rs

@@ -134,6 +134,7 @@ pub fn elf_to_tbf(
     permissions: Vec<(u32, u32)>,
     storage_ids: (Option<u32>, Option<Vec<u32>>, Option<Vec<u32>>),
     kernel_version: Option<(u16, u16)>,
+    short_id: Option<u32>,
     disabled: bool,
     minimum_footer_size: u32,
     app_version: u32,
@@ -460,6 +461,7 @@ pub fn elf_to_tbf(
         permissions,
         storage_ids,
         kernel_version,
+        short_id,
         disabled,
     );
 

src/header.rs

@@ -18,8 +18,8 @@ pub enum TbfHeaderTypes {
     Permissions = 6,
     Persistent = 7,
     KernelVersion = 8,
-
     Program = 9,
+    ShortId = 10,
 
     Credentials = 128,
 }
@@ -124,6 +124,13 @@ struct TbfHeaderKernelVersion {
     minor: u16,
 }
 
+#[repr(C)]
+#[derive(Clone, Copy, Debug)]
+struct TbfHeaderShortId {
+    base: TbfHeaderTlv,
+    short_id: u32,
+}
+
 #[repr(C)]
 #[derive(Debug)]
 pub struct TbfFooterCredentials {
@@ -275,6 +282,18 @@ impl fmt::Display for TbfHeaderKernelVersion {
     }
 }
 
+impl fmt::Display for TbfHeaderShortId {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        // ^x.y means >= x.y, < (x+1).0
+        writeln!(
+            f,
+            "
+               ShortId: {0:>#10X}",
+            self.short_id
+        )
+    }
+}
+
 const FLAGS_ENABLE: u32 = 0x0000_0001;
 
 pub struct TbfHeader {
@@ -287,6 +306,7 @@ pub struct TbfHeader {
     hdr_permissions: Option<TbfHeaderPermissions>,
     hdr_persistent: Option<TbfHeaderPersistentAcl>,
     hdr_kernel_version: Option<TbfHeaderKernelVersion>,
+    hdr_short_id: Option<TbfHeaderShortId>,
     package_name: String,
     package_name_pad: usize,
 }
@@ -318,6 +338,7 @@ impl TbfHeader {
             hdr_permissions: None,
             hdr_persistent: None,
             hdr_kernel_version: None,
+            hdr_short_id: None,
             package_name: String::new(),
             package_name_pad: 0,
         }
@@ -340,6 +361,7 @@ impl TbfHeader {
         permissions: Vec<(u32, u32)>,
         storage_ids: (Option<u32>, Option<Vec<u32>>, Option<Vec<u32>>),
         kernel_version: Option<(u16, u16)>,
+        short_id: Option<u32>,
         disabled: bool,
     ) -> usize {
         // Need to calculate lengths ahead of time. Need the base and the
@@ -435,6 +457,11 @@ impl TbfHeader {
             header_length += mem::size_of::<TbfHeaderKernelVersion>();
         }
 
+        // Check if we have to include a kernel version header.
+        if short_id.is_some() {
+            header_length += mem::size_of::<TbfHeaderShortId>();
+        }
+
         let mut flags = 0x0000_0000;
 
         if !disabled {
@@ -534,6 +561,17 @@ impl TbfHeader {
             });
         }
 
+        // If short_id is set, we have to include the header.
+        if let Some(short_id_num) = short_id {
+            self.hdr_short_id = Some(TbfHeaderShortId {
+                base: TbfHeaderTlv {
+                    tipe: TbfHeaderTypes::ShortId,
+                    length: 4,
+                },
+                short_id: short_id_num,
+            });
+        }
+
         // Return the length by generating the header and seeing how long it is.
         self.generate()
             .expect("No header was generated")
@@ -678,6 +716,11 @@ impl TbfHeader {
             header_buf.write_all(unsafe { util::as_byte_slice(&self.hdr_kernel_version) })?;
         }
 
+        // If the short id is set, include that TLV
+        if self.hdr_short_id.is_some() {
+            header_buf.write_all(unsafe { util::as_byte_slice(&self.hdr_short_id) })?;
+        }
+
         let current_length = header_buf.get_ref().len();
         util::do_pad(
             &mut header_buf,
@@ -746,6 +789,8 @@ impl fmt::Display for TbfHeader {
             .map_or(Ok(()), |hdr| write!(f, "{}", hdr))?;
         self.hdr_kernel_version
             .map_or(Ok(()), |hdr| write!(f, "{}", hdr))?;
+        self.hdr_short_id
+            .map_or(Ok(()), |hdr| write!(f, "{}", hdr))?;
         Ok(())
     }
 }

src/main.rs

@@ -138,6 +138,7 @@ fn main() {
             opt.permissions.to_vec(),
             (opt.write_id, opt.read_ids.clone(), opt.access_ids.clone()),
             minimum_tock_kernel_version,
+            opt.short_id,
             opt.disabled,
             opt.minimum_footer_size,
             opt.app_version,