thiserror, docs, remove general Failure case (#9741)

automerge

sdk/src/hash.rs

@@ -1,5 +1,6 @@
 //! The `hash` module provides functions for creating SHA-256 hashes.
 
+use crate::sanitize::Sanitize;
 use sha2::{Digest, Sha256};
 use std::{convert::TryFrom, fmt, mem, str::FromStr};
 use thiserror::Error;
@@ -30,6 +31,8 @@ impl Hasher {
     }
 }
 
+impl Sanitize for Hash {}
+
 impl AsRef<[u8]> for Hash {
     fn as_ref(&self) -> &[u8] {
         &self.0[..]

sdk/src/instruction.rs

@@ -1,5 +1,6 @@
 //! Defines a composable Instruction type and a memory-efficient CompiledInstruction.
 
+use crate::sanitize::Sanitize;
 use crate::{pubkey::Pubkey, short_vec, system_instruction::SystemError};
 use bincode::serialize;
 use serde::Serialize;
@@ -252,6 +253,8 @@ pub struct CompiledInstruction {
     pub data: Vec<u8>,
 }
 
+impl Sanitize for CompiledInstruction {}
+
 impl CompiledInstruction {
     pub fn new<T: Serialize>(program_ids_index: u8, data: &T, accounts: Vec<u8>) -> Self {
         let data = serialize(data).unwrap();

sdk/src/message.rs

@@ -184,6 +184,9 @@ impl Sanitize for Message {
                 }
             }
         }
+        self.account_keys.sanitize()?;
+        self.recent_blockhash.sanitize()?;
+        self.instructions.sanitize()?;
         Ok(())
     }
 }

sdk/src/sanitize.rs

@@ -1,11 +1,22 @@
-#[derive(PartialEq, Debug)]
+use thiserror::Error;
+
+#[derive(PartialEq, Debug, Error, Eq, Clone)]
 pub enum SanitizeError {
-    Failed,
+    #[error("index out of bounds")]
     IndexOutOfBounds,
-    ValueOutOfRange,
+    #[error("value out of bounds")]
+    ValueOutOfBounds,
+    #[error("invalid value")]
     InvalidValue,
 }
 
+/// Trait for sanitizing values and members of over the wire messages.
+/// Implementation should recursively decent through the data structure
+/// and sanitize all struct members and enum clauses.  Sanitize excludes
+/// signature verification checks, those are handled by another pass.
+/// Sanitize checks should include but are not limited too:
+///   * All index values are in range
+///   * All values are within their static max/min bounds
 pub trait Sanitize {
     fn sanitize(&self) -> Result<(), SanitizeError> {
         Ok(())