xtask/starfive/visionfive2: rework header to using structs

This is based on what the vendor tool does. No clue how the secure boot flow or setup really works. Reference: starfive-tech/Tools#8 Signed-off-by: Daniel Maslowski <[email protected]>
orangecms · Feb 9, 2024 · d100b0a · d100b0a
1 parent 53a8983
commit d100b0a
Showing 1 changed file with 93 additions and 22 deletions.
diff --git a/xtask/src/starfive/visionfive2_hdr.rs b/xtask/src/starfive/visionfive2_hdr.rs
@@ -36,18 +36,49 @@ const BACKUP_OFFSET_BYTES: [u8; 4] = BACKUP_OFFSET.to_le_bytes();
 const HEADER_SIZE: u32 = 0x0400;
 const HEADER_SIZE_BYTES: [u8; 4] = HEADER_SIZE.to_le_bytes();
 
-/* this is a shortcut */
-const VERSION_OFFSET: usize = HEADER_OFFSET as usize + 0x0044;
+#[repr(C)]
+struct Version {
+    major: u8,
+    minor: u8,
+    revision: u16,
+}
+
+#[repr(C)]
+struct JH7110CommonHeader {
+    // the offset to the other header
+    size: u32,
+    backup_offset: u32,
+    _unknown1: u64,
+    _skip1: [u8; 48],
+    // 0x040
+    ec_param_p: [u8; 32],
+    ec_param_a: [u8; 32],
+    ec_param_b: [u8; 32],
+    ec_param_gx: [u8; 32],
+    ec_param_gy: [u8; 32],
+    ec_param_n: [u8; 32],
+    _skip2: [u8; 64],
+    // 0x140
+    ec_key_1: [u8; 64],
+    ec_key_2: [u8; 64],
+    ec_key_3: [u8; 64],
+    ec_key_4: [u8; 64],
+}
 
-/* version: shall be 0x01010101
- * (from https://doc-en.rvspace.org/VisionFive2/SWTRM/VisionFive2_SW_TRM/create_spl.html) */
-const VERSION: u32 = 0x0101_0101;
-const VERSION_BYTES: [u8; 4] = VERSION.to_le_bytes();
+#[repr(C)]
+struct JH7110SBLHeader {
+    // NOTE: there may be other optional fields here; unclear
+    _skip1: [u8; 0x40],
+    ec_key_select: u32,
+    version: Version,
+    payload_size: u32,
+    header_size: u32,
+    checksum: u32,
+    aes_iv: [u8; 16],
+    ec_key_revoke: [u8; 32],
+    sbl_ver_cipher: [u8; 16],
+}
 
-// The use of a packed struct is kind of pointless.
-// Just emit the proper things in the proper order.
-// Push them into the output.
-// Also, let's get real: there are no big-endian machines left. Assume LE.
 pub fn spl_create_hdr(dat: Vec<u8>) -> Vec<u8> {
     /*
         // need to find out which one to use, but it's not this one.
@@ -58,20 +89,60 @@ pub fn spl_create_hdr(dat: Vec<u8>) -> Vec<u8> {
         let crcout = digest.finalize();
     }
     */
-    let v = crc32(CRC_IV, CRC_SV, dat.clone());
-    let checksum: [u8; 4] = v.to_le_bytes();
-    let data_len: [u8; 4] = (dat.len() as u32).to_le_bytes();
+    let checksum = crc32(CRC_IV, CRC_SV, dat.clone());
+
+    let common_header = JH7110CommonHeader {
+        size: HEADER_OFFSET,
+        backup_offset: BACKUP_OFFSET,
+        _unknown1: 0,
+        _skip1: [0u8; 0x30],
+        ec_param_p: [0u8; 0x20],
+        ec_param_a: [0u8; 0x20],
+        ec_param_b: [0u8; 0x20],
+        ec_param_gx: [0u8; 0x20],
+        ec_param_gy: [0u8; 0x20],
+        ec_param_n: [0u8; 0x20],
+        _skip2: [0u8; 0x40],
+        ec_key_1: [0u8; 0x40],
+        ec_key_2: [0u8; 0x40],
+        ec_key_3: [0u8; 0x40],
+        ec_key_4: [0u8; 0x40],
+    };
+
+    let sbl_header = JH7110SBLHeader {
+        _skip1: [0u8; 0x40],
+        // TODO: This needs to be a parameter for "secure boot" setup.
+        // 4 slots are available; 0 means use none, 1 means first, 4 is maximum.
+        ec_key_select: 0,
+        /* version: shall be 0x01010101
+         * https://doc-en.rvspace.org/VisionFive2/SWTRM/VisionFive2_SW_TRM/create_spl.html */
+        version: Version {
+            major: 1,
+            minor: 1,
+            revision: 0x101,
+        },
+        payload_size: dat.len() as u32,
+        header_size: HEADER_SIZE,
+        checksum,
+        aes_iv: [0u8; 16],
+        ec_key_revoke: [0u8; 32],
+        sbl_ver_cipher: [0u8; 16],
+    };
 
     let mut hdr = vec![];
-    hdr.extend_from_slice(&HEADER_OFFSET_BYTES);
-    hdr.extend_from_slice(&BACKUP_OFFSET_BYTES);
-    hdr.resize(HEADER_OFFSET as usize, 0);
-    // NOTE: there are apparently other optional fields, unused here as of now
-    hdr.resize(VERSION_OFFSET, 0);
-    hdr.extend_from_slice(&VERSION_BYTES);
-    hdr.extend_from_slice(&data_len);
-    hdr.extend_from_slice(&HEADER_SIZE_BYTES);
-    hdr.extend_from_slice(&checksum);
+
+    let ch = unsafe {
+        std::slice::from_raw_parts(
+            (&common_header as *const JH7110CommonHeader) as *const u8,
+            0x240,
+        )
+    };
+    let sh = unsafe {
+        std::slice::from_raw_parts((&sbl_header as *const JH7110SBLHeader) as *const u8, 0x94)
+    };
+    hdr.extend_from_slice(ch);
+    hdr.extend_from_slice(sh);
+
     hdr.resize(HEADER_SIZE as usize, 0);
     hdr.extend(&dat);
     hdr