let Manifest own its remaining data

orangecms · orangecms · commit 211c493d40fc · 2025-11-17T00:25:14.000+01:00
Split out the header and manifest key/signature material.

Signed-off-by: Daniel Maslowski &lt;info@orangecms.org&gt;
diff --git a/src/dir/gen2.rs b/src/dir/gen2.rs
@@ -8,7 +8,7 @@ use zerocopy::{FromBytes, Ref};
 use zerocopy_derive::{FromBytes, Immutable, IntoBytes};
 
 use crate::Removables;
-use crate::dir::man::{self, Manifest};
+use crate::dir::man::Manifest;
 
 // These must never be removed. They are essential for platform initialization.
 pub const ALWAYS_RETAIN: &[&str] = &[
@@ -197,7 +197,7 @@ pub struct Header {
 #[derive(Serialize, Deserialize, Clone, Debug)]
 #[repr(C)]
 pub struct Directory {
-    pub manifest: (Manifest, Vec<u8>),
+    pub manifest: Manifest,
     pub header: Header,
     pub modules: Vec<Module>,
     pub offset: usize,
@@ -210,7 +210,7 @@ impl Display for Directory {
         let n = &self.name;
         let o = self.offset;
         let s = self.size;
-        let (m, _) = self.manifest;
+        let m = &self.manifest;
         write!(f, "{n} @ {o:08x}, {s} bytes, {m}")
     }
 }
@@ -222,11 +222,7 @@ impl Directory {
         let Ok(manifest) = Manifest::new(data) else {
             return Err("cannot parse Gen 2 directory manifest".to_string());
         };
-
-        let data_len = manifest.data_len();
-        let mdata = &data[man::MANIFEST_SIZE..man::MANIFEST_SIZE + data_len];
-
-        let Ok((header, _)) = Header::read_from_prefix(mdata) else {
+        let Ok((header, _)) = Header::read_from_prefix(&manifest.mdata) else {
             return Err("cannot parse ME FW Gen 2 directory header".to_string());
         };
         let name = match from_utf8(&header.name) {
@@ -236,20 +232,17 @@ impl Directory {
 
         // Check magic bytes of first entry.
         let pos = HEADER_SIZE;
-        let m = &mdata[pos..pos + 4];
+        let slice = &manifest.mdata[pos..];
+        let m = &slice[..4];
         if !m.eq(MODULE_MAGIC_BYTES) {
             return Err(format!(
                 "entry magic not found, got {m:02x?}, wanted {MODULE_MAGIC_BYTES:02x?} ({MODULE_MAGIC})"
             ));
         }
         // Parse the entries themselves.
-        let slice = &mdata[pos..];
         let count = manifest.header.entries as usize;
         let Ok((r, _)) = Ref::<_, [Entry]>::from_prefix_with_elems(slice, count) else {
-            return Err(format!(
-                "cannot parse ME FW Gen 2 directory entries @ {:08x}",
-                pos
-            ));
+            return Err(format!("cannot parse ME FW Gen 2 directory entries",));
         };
         let entries = r.to_vec();
 
@@ -299,7 +292,7 @@ impl Directory {
 
         let size = data.len();
         Ok(Self {
-            manifest: (manifest, mdata.to_vec()),
+            manifest,
             header,
             modules,
             offset,
diff --git a/src/dir/gen3.rs b/src/dir/gen3.rs
@@ -104,7 +104,7 @@ impl Display for CPDEntry {
 #[repr(C)]
 pub struct CodePartitionDirectory {
     pub header: CPDHeader,
-    pub manifest: Result<(Manifest, Vec<u8>), String>,
+    pub manifest: Result<Manifest, String>,
     pub entries: Vec<CPDEntry>,
     pub offset: usize,
     pub size: usize,
@@ -125,7 +125,7 @@ impl Display for CodePartitionDirectory {
         let n = &self.name;
         let l1 = format!("{n} @ {o:08x}, checksum or version: {checksum:08x}");
         let l2 = match &self.manifest {
-            Ok((m, _)) => {
+            Ok(m) => {
                 let h = stringify_vec(m.hash_key());
                 let m = format!("{m}");
                 let kh = format!("Key hash: {h}");
@@ -174,16 +174,7 @@ impl CodePartitionDirectory {
             if let Some(e) = entries.iter().find(|e| e.name() == manifest_name) {
                 let o = e.flags_and_offset.offset() as usize;
                 let end = o + e.size as usize;
-                match Manifest::new(&data[o..end]) {
-                    Ok(m) => {
-                        // The manifest carries additional data after its header
-                        // and key material.
-                        let header_len = m.header_len();
-                        let mdata = data[o + header_len..end].to_vec();
-                        Ok((m, mdata))
-                    }
-                    Err(e) => Err(e),
-                }
+                Manifest::new(&data[o..end])
             } else {
                 Err("no manifest found".to_string())
             }
diff --git a/src/dir/man.rs b/src/dir/man.rs
@@ -64,7 +64,7 @@ pub struct Header {
     pub flags: u32,
     pub vendor: Vendor,
     pub date: Date,
-    pub size: u32, // in dwords, dword size is 32bit
+    pub manifest_len: u32, // in dwords, dword size is 32bit
     pub magic: [u8; 4],
     // NOTE: only for Gen 2 ME firmware
     pub entries: u32,
@@ -93,79 +93,106 @@ impl Display for Header {
     }
 }
 
+impl Header {
+    /// Get the header length including signature
+    pub fn header_len(&self) -> usize {
+        self.header_len as usize * 4
+    }
+
+    /// Get the length of the manifest including its data
+    pub fn manifest_len(&self) -> usize {
+        self.manifest_len as usize * 4
+    }
+
+    /// Get the length of the data after the header
+    pub fn data_len(&self) -> usize {
+        let mlen = self.manifest_len();
+        let hlen = self.header_len();
+        mlen - hlen
+    }
+}
+
 #[derive(Immutable, IntoBytes, FromBytes, Serialize, Deserialize, Clone, Copy, Debug)]
 #[repr(C)]
-pub struct Manifest {
-    pub header: Header,
+pub struct Signature {
     #[serde(with = "serde_bytes")]
     pub rsa_pub_key: [u8; 0x100],
     pub rsa_pub_exp: u32,
     #[serde(with = "serde_bytes")]
     pub rsa_sig: [u8; 0x100],
 }
 
+#[derive(Serialize, Deserialize, Clone, Debug)]
+#[repr(C)]
+pub struct Manifest {
+    pub header: Header,
+    pub signature: Signature,
+    pub mdata: Vec<u8>,
+}
+
 pub const MANIFEST_SIZE: usize = core::mem::size_of::<Manifest>();
 
 impl<'a> Manifest {
     pub fn new(data: &'a [u8]) -> Result<Self, String> {
-        let (manifest, _) = match Self::read_from_prefix(data) {
+        let (header, slice) = match Header::read_from_prefix(data) {
             Ok(r) => r,
             Err(e) => {
                 let err = format!("Manifest cannot be parsed: {e:?}");
                 return Err(err);
             }
         };
 
-        if manifest.header.magic != MANIFEST2_MAGIC_BYTES {
+        if header.magic != MANIFEST2_MAGIC_BYTES {
             let err = format!(
                 "Manifest magic not found: wanted {MANIFEST2_MAGIC_BYTES:02x?} ({MANIFEST2_MAGIC}), got {:02x?}",
-                manifest.header.magic
+                header.magic
             );
             return Err(err);
         }
 
-        Ok(manifest)
-    }
-
-    /// Get the header length
-    pub fn header_len(&self) -> usize {
-        self.header.header_len as usize * 4
-    }
-
-    /// Get the size of the manifest and its data
-    pub fn size(&self) -> usize {
-        self.header.size as usize * 4
-    }
+        let (signature, _) = match Signature::read_from_prefix(slice) {
+            Ok(r) => r,
+            Err(e) => {
+                let err = format!("Signature cannot be parsed: {e:?}");
+                return Err(err);
+            }
+        };
 
-    /// Get the length of the data after the manifest
-    pub fn data_len(&self) -> usize {
-        let mlen = self.size();
-        let hlen = self.header_len();
-        mlen - hlen
+        // The manifest carries additional data after its header and signature.
+        // Note that header_len includes the signature.
+        let header_len = header.header_len();
+        let size = header.manifest_len();
+        let mdata = &data[header_len..size];
+
+        Ok(Self {
+            header,
+            signature,
+            mdata: mdata.to_vec(),
+        })
     }
 
     /// Get the MD5 hash over the RSA public key and exponent.
-    pub fn hash_key(self: Self) -> Vec<u8> {
-        let k = self.rsa_pub_key.as_bytes();
-        let e = self.rsa_pub_exp;
+    pub fn hash_key(&self) -> Vec<u8> {
+        let k = self.signature.rsa_pub_key.as_bytes();
+        let e = self.signature.rsa_pub_exp;
         let ke = [k, &e.to_le_bytes()].concat();
         md5::compute(ke).to_vec()
     }
 
-    /// Verify the manifest. Pass extra bytes from after the manifest.
-    pub fn verify(&self, ebytes: &[u8]) -> bool {
+    /// Verify the manifest.
+    pub fn verify(&self) -> bool {
         use num_bigint::BigUint;
         use sha2::{Digest, Sha256};
 
-        let modulus = BigUint::from_bytes_le(&self.rsa_pub_key);
-        let exponent = BigUint::from(self.rsa_pub_exp);
-        let signature = BigUint::from_bytes_le(&self.rsa_sig);
+        let modulus = BigUint::from_bytes_le(&self.signature.rsa_pub_key);
+        let exponent = BigUint::from(self.signature.rsa_pub_exp);
+        let signature = BigUint::from_bytes_le(&self.signature.rsa_sig);
         let sb = signature.modpow(&exponent, &modulus).to_bytes_be();
 
         let header = self.header.as_bytes();
         let mut hasher = Sha256::new();
         hasher.update(&header);
-        hasher.update(&ebytes);
+        hasher.update(&self.mdata);
         let hash = hasher.finalize();
         let hb = hash.as_bytes();
 
@@ -177,7 +204,7 @@ impl<'a> Manifest {
 impl Display for Manifest {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let h = self.header;
-        let exp = self.rsa_pub_exp;
+        let exp = self.signature.rsa_pub_exp;
         write!(f, "{h}, RSA exp {exp}")
     }
 }
diff --git a/src/part/gen2.rs b/src/part/gen2.rs
@@ -20,8 +20,7 @@ pub struct DirPartition {
 
 impl DirPartition {
     pub fn check_signature(&self) -> Result<(), String> {
-        let (m, mdata) = &self.dir.manifest;
-        if m.verify(&mdata) {
+        if self.dir.manifest.verify() {
             return Ok(());
         } else {
             return Err("hash mismatch".into());
diff --git a/src/part/gen3.rs b/src/part/gen3.rs
@@ -21,8 +21,8 @@ pub struct CPDPartition {
 
 impl CPDPartition {
     pub fn check_signature(&self) -> Result<(), String> {
-        if let Ok((m, mdata)) = &self.cpd.manifest {
-            if m.verify(&mdata) {
+        if let Ok(m) = &self.cpd.manifest {
+            if m.verify() {
                 return Ok(());
             } else {
                 return Err("hash mismatch".into());
diff --git a/src/part/partitions.rs b/src/part/partitions.rs
@@ -79,7 +79,7 @@ impl Partitions {
                 if let Some(Gen2Partition::Dir(d)) =
                     parts.iter().find(|p| matches!(p, Gen2Partition::Dir(_)))
                 {
-                    let (m, _) = d.dir.manifest;
+                    let m = &d.dir.manifest;
                     Some(m.header.version)
                 } else {
                     None
@@ -89,7 +89,7 @@ impl Partitions {
                 if let Some(Gen3Partition::Dir(d)) =
                     parts.iter().find(|p| matches!(p, Gen3Partition::Dir(_)))
                 {
-                    if let Ok((m, _)) = d.cpd.manifest {
+                    if let Ok(m) = &d.cpd.manifest {
                         Some(m.header.version)
                     } else {
                         None
