From 6db572ce650d76450db51739229472139b5b7ada Mon Sep 17 00:00:00 2001
From: Arnaud Gourlay <arnaud.gourlay@gmail.com>
Date: Thu, 23 May 2024 20:12:22 +0200
Subject: [PATCH] review & clippy

---
 src/aes.rs    |  8 +++++---
 src/read.rs   | 32 +++++++++++++++++++++++---------
 src/result.rs |  4 ----
 3 files changed, 28 insertions(+), 16 deletions(-)

diff --git a/src/aes.rs b/src/aes.rs
index 3050263a..45e20e3b 100644
--- a/src/aes.rs
+++ b/src/aes.rs
@@ -15,7 +15,7 @@ use std::io::{self, Error, ErrorKind, Read, Write};
 use zeroize::{Zeroize, Zeroizing};
 
 /// The length of the password verifcation value in bytes
-const PWD_VERIFY_LENGTH: usize = 2;
+pub const PWD_VERIFY_LENGTH: usize = 2;
 /// The length of the authentication code in bytes
 const AUTH_CODE_LENGTH: usize = 10;
 /// The number of iterations used with PBKDF2
@@ -130,14 +130,16 @@ impl<R: Read> AesReader<R> {
     /// # Returns
     ///
     /// the verification value and the salt
-    pub fn get_verification_value_and_salt(mut self) -> io::Result<(Vec<u8>, Vec<u8>)> {
+    pub fn get_verification_value_and_salt(
+        mut self,
+    ) -> io::Result<([u8; PWD_VERIFY_LENGTH], Vec<u8>)> {
         let salt_length = self.aes_mode.salt_length();
 
         let mut salt = vec![0; salt_length];
         self.reader.read_exact(&mut salt)?;
 
         // next are 2 bytes used for password verification
-        let mut pwd_verification_value = vec![0; PWD_VERIFY_LENGTH];
+        let mut pwd_verification_value = [0; PWD_VERIFY_LENGTH];
         self.reader.read_exact(&mut pwd_verification_value)?;
         Ok((pwd_verification_value, salt))
     }
diff --git a/src/read.rs b/src/read.rs
index 3c9b36b6..81d17100 100644
--- a/src/read.rs
+++ b/src/read.rs
@@ -82,6 +82,7 @@ pub(crate) mod zip_archive {
     }
 }
 
+use crate::aes::PWD_VERIFY_LENGTH;
 #[cfg(feature = "lzma")]
 use crate::read::lzma::LzmaDecoder;
 use crate::result::ZipError::{InvalidPassword, UnsupportedArchive};
@@ -647,33 +648,35 @@ impl<R: Read + Seek> ZipArchive<R> {
 
     /// Returns the verification value and salt for the AES encryption of the file
     ///
-    /// It fails if the file is not encrypted or if the file number is invalid.
+    /// It fails if the file number is invalid.
     ///
     /// # Returns
     ///
-    /// - Some with the verification value and the salt
     /// - None if the file is not encrypted with AES
     #[cfg(feature = "aes-crypto")]
     pub fn get_aes_verification_key_and_salt(
         &mut self,
         file_number: usize,
-    ) -> ZipResult<Option<(AesMode, Vec<u8>, Vec<u8>)>> {
+    ) -> ZipResult<Option<AesInfo>> {
         let (_, data) = self
             .shared
             .files
             .get_index(file_number)
             .ok_or(ZipError::FileNotFound)?;
 
-        if !data.encrypted {
-            return Err(ZipError::UnsupportedArchive(ZipError::ARCHIVE_NOT_ENCRYPTED));
-        }
         let limit_reader = find_content(data, &mut self.reader)?;
         match data.aes_mode {
             None => Ok(None),
             Some((aes_mode, _, _)) => {
-                let (key, salt) = AesReader::new(limit_reader, aes_mode, data.compressed_size)
-                    .get_verification_value_and_salt()?;
-                Ok(Some((aes_mode, key, salt)))
+                let (verification_value, salt) =
+                    AesReader::new(limit_reader, aes_mode, data.compressed_size)
+                        .get_verification_value_and_salt()?;
+                let aes_info = AesInfo {
+                    aes_mode,
+                    verification_value,
+                    salt,
+                };
+                Ok(Some(aes_info))
             }
         }
     }
@@ -970,6 +973,17 @@ impl<R: Read + Seek> ZipArchive<R> {
     }
 }
 
+/// Holds the AES information of a file in the zip archive
+#[derive(Debug)]
+pub struct AesInfo {
+    /// The AES encryption mode
+    pub aes_mode: AesMode,
+    /// The verification key
+    pub verification_value: [u8; PWD_VERIFY_LENGTH],
+    /// The salt
+    pub salt: Vec<u8>,
+}
+
 const fn unsupported_zip_error<T>(detail: &'static str) -> ZipResult<T> {
     Err(ZipError::UnsupportedArchive(detail))
 }
diff --git a/src/result.rs b/src/result.rs
index a3a467a8..7bd5cad5 100644
--- a/src/result.rs
+++ b/src/result.rs
@@ -46,10 +46,6 @@ impl ZipError {
     /// # ()
     /// ```
     pub const PASSWORD_REQUIRED: &'static str = "Password required to decrypt file";
-
-
-    /// The text used as an error when the archive is not encrypted
-    pub const ARCHIVE_NOT_ENCRYPTED: &'static str = "the archive is not encrypted";
 }
 
 impl From<ZipError> for io::Error {