[opentitantool] Finish renaming legacy Google rescue protocol

Previous generation of Google Titan security chips supported a UART
"rescue" bootstrapping protocol.  This PR ensures that that protocol is
exclusively referred to as the "legacy rescue" protocol.  This makes
room for an implementation of the OpenTitan UART rescue protocol to be
invoked by the short form `--protocol=rescue`.

Change-Id: Ice36b21e1a44b55a32be963c8c47934a6799bf81
Signed-off-by: Jes B. Klinke <[email protected]>
(cherry picked from commit 6eed8df)

sw/host/opentitanlib/BUILD

@@ -67,9 +67,9 @@ rust_library(
         "src/backend/verilator.rs",
         "src/bootstrap/eeprom.rs",
         "src/bootstrap/legacy.rs",
+        "src/bootstrap/legacy_rescue.rs",
         "src/bootstrap/mod.rs",
         "src/bootstrap/primitive.rs",
-        "src/bootstrap/rescue.rs",
         "src/chip/alert.rs",
         "src/chip/autogen/mod.rs",
         "src/chip/boolean.rs",

sw/host/opentitanlib/src/bootstrap/rescue.rs → sw/host/opentitanlib/src/bootstrap/legacy_rescue.rs

@@ -82,7 +82,7 @@ impl Frame {
 
         ensure!(
             payload.starts_with(&Self::MAGIC_HEADER),
-            RescueError::ImageFormatError
+            LegacyRescueError::ImageFormatError
         );
 
         // Find second occurrence of magic value, not followed by signature of encrypted
@@ -92,7 +92,7 @@ impl Frame {
             .position(|c| c[0..4] == Self::MAGIC_HEADER && c[4..8] != Self::CRYPTOLIB_TELL)
         {
             Some(n) => (n + 1) * Self::HEADER_ALIGNMENT,
-            None => bail!(RescueError::ImageFormatError),
+            None => bail!(LegacyRescueError::ImageFormatError),
         };
 
         // Inspect the length field of the RW header.
@@ -160,27 +160,27 @@ impl Frame {
 }
 
 #[derive(Debug, Error, serde::Serialize, serde::Deserialize)]
-pub enum RescueError {
+pub enum LegacyRescueError {
     #[error("Unrecognized image file format")]
     ImageFormatError,
     #[error("Synchronization error communicating with boot rom")]
     SyncError,
     #[error("Repeated errors communicating with boot rom")]
     RepeatedErrors,
 }
-impl_serializable_error!(RescueError);
+impl_serializable_error!(LegacyRescueError);
 
 /// Implements the UART rescue protocol of Google Ti50 firmware.
-pub struct Rescue {}
+pub struct LegacyRescue {}
 
-impl Rescue {
+impl LegacyRescue {
     /// Abort if a block has not been accepted after this number of retries.
     const MAX_CONSECUTIVE_ERRORS: u32 = 50;
     /// Take some measure to regain protocol synchronization, in case of this number of retries
     /// of the same block.
     const RESYNC_AFTER_CONSECUTIVE_ERRORS: u32 = 3;
 
-    /// Creates a new `Rescue` protocol updater from `options`.
+    /// Creates a new `LegacyRescue` protocol updater from `options`.
     pub fn new(_options: &BootstrapOptions) -> Self {
         Self {}
     }
@@ -248,7 +248,7 @@ impl Rescue {
                 }
             }
         }
-        Err(RescueError::SyncError.into())
+        Err(LegacyRescueError::SyncError.into())
     }
 
     /// Reset the chip and send the magic 'r' character at the opportune moment during boot in
@@ -286,11 +286,11 @@ impl Rescue {
             }
             eprintln!(" Failed to enter rescue mode.");
         }
-        Err(RescueError::RepeatedErrors.into())
+        Err(LegacyRescueError::RepeatedErrors.into())
     }
 }
 
-impl UpdateProtocol for Rescue {
+impl UpdateProtocol for LegacyRescue {
     fn verify_capabilities(
         &self,
         _container: &Bootstrap,
@@ -360,7 +360,7 @@ impl UpdateProtocol for Rescue {
                     }
                 }
             }
-            bail!(RescueError::RepeatedErrors);
+            bail!(LegacyRescueError::RepeatedErrors);
         }
 
         // Reset, in order to leave rescue mode.

sw/host/opentitanlib/src/bootstrap/mod.rs

@@ -19,11 +19,11 @@ use crate::transport::{Capability, ProgressIndicator};
 
 mod eeprom;
 mod legacy;
+mod legacy_rescue;
 mod primitive;
-mod rescue;
 
 pub use legacy::LegacyBootstrapError;
-pub use rescue::RescueError;
+pub use legacy_rescue::LegacyRescueError;
 
 #[derive(Debug, Error, Serialize, Deserialize)]
 pub enum BootstrapError {
@@ -37,7 +37,6 @@ impl_serializable_error!(BootstrapError);
 /// The `Legacy` SPI protocol is used by previous generations of Google Titan-class chips.
 /// The `LegacyRescue` UART protocol is used by previous generations of Google Titan-class chips.
 /// The `Eeprom` SPI protocol is planned to be implemented for OpenTitan.
-/// The `Rescue` value is a deprecated alias for `LegacyRescue`.
 /// The 'Emulator' value indicates that this tool has a direct way
 /// of communicating with the OpenTitan emulator, to replace the
 /// contents of the emulated flash storage.
@@ -47,7 +46,6 @@ pub enum BootstrapProtocol {
     Legacy,
     LegacyRescue,
     Eeprom,
-    Rescue,
     Emulator,
 }
 
@@ -147,8 +145,7 @@ impl<'a> Bootstrap<'a> {
         let updater: Box<dyn UpdateProtocol> = match options.protocol {
             BootstrapProtocol::Primitive => Box::new(primitive::Primitive::new(options)),
             BootstrapProtocol::Legacy => Box::new(legacy::Legacy::new(options)),
-            BootstrapProtocol::LegacyRescue => Box::new(rescue::Rescue::new(options)),
-            BootstrapProtocol::Rescue => Box::new(rescue::Rescue::new(options)),
+            BootstrapProtocol::LegacyRescue => Box::new(legacy_rescue::LegacyRescue::new(options)),
             BootstrapProtocol::Eeprom => Box::new(eeprom::Eeprom::new()),
             BootstrapProtocol::Emulator => {
                 // Not intended to be implemented by this struct.

sw/host/opentitanlib/src/proxy/errors.rs

@@ -111,7 +111,7 @@ impl From<anyhow::Error> for SerializedError {
             Box::new,
             crate::bootstrap::BootstrapError,
             crate::bootstrap::LegacyBootstrapError,
-            crate::bootstrap::RescueError,
+            crate::bootstrap::LegacyRescueError,
             crate::io::console::ConsoleError,
             crate::io::emu::EmuError,
             crate::io::gpio::GpioError,