always seek file to start before starting extractor

src/formats/amlogic/mod.rs

@@ -4,7 +4,7 @@ use crate::AppContext;
 
 use std::path::Path;
 use std::fs::{self, OpenOptions};
-use std::io::{Write, Seek, SeekFrom};
+use std::io::Write;
 use binrw::BinReaderExt;
 
 use crate::utils::common;
@@ -25,9 +25,7 @@ pub fn is_amlogic_file(app_ctx: &AppContext) -> Result<Option<Box<dyn Any>>, Box
 pub fn extract_amlogic(app_ctx: &AppContext, _ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
     let mut file = app_ctx.file().ok_or("Extractor expected file")?;
 
-    file.seek(SeekFrom::Start(0))?;
     let header: ImageHeader = file.read_le()?;
-
     println!("File info -\nImage size: {}\nItem align size: {}\nItem count: {}\nFormat version: {}", 
             header.image_size, header.item_align_size, header.item_count, header.version);
 

src/formats/epk/mod.rs

@@ -1,4 +1,5 @@
 use std::any::Any;
+use std::io::Seek;
 use crate::AppContext;
 
 use crate::utils::common;
@@ -49,7 +50,7 @@ fn match_with_pattern(data: &[u8], pattern: &str) -> bool {
 }
 
 pub fn extract_epk(app_ctx: &AppContext, ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
-    let file = app_ctx.file().ok_or("Extractor expected file")?;
+    let mut file = app_ctx.file().ok_or("Extractor expected file")?;
     let ctx = ctx.downcast::<EpkContext>().expect("Missing context");
 
     let versions = common::read_file(&file, 1712, 36)?;
@@ -58,6 +59,8 @@ pub fn extract_epk(app_ctx: &AppContext, ctx: Box<dyn Any>) -> Result<(), Box<dy
     let sdk_version = common::string_from_bytes(&versions[20..36]);
     println!("Platform version: {}\nSDK version: {}", platform_version, sdk_version);
     
+    file.seek(std::io::SeekFrom::Start(0))?;
+
     if ctx.epk_version == 2 {
         println!("EPK2 detected!\n");
         formats::epk2::extract_epk2(app_ctx, Box::new(()))?;

src/formats/epk2/mod.rs

@@ -25,7 +25,6 @@ pub fn is_epk2_file(app_ctx: &AppContext) -> Result<Option<Box<dyn Any>>, Box<dy
 
 pub fn extract_epk2(app_ctx: &AppContext, _ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
     let mut file = app_ctx.file().ok_or("Extractor expected file")?;
-    file.seek(SeekFrom::Start(0))?;
 
     let _header_signature = common::read_exact(&mut file, SIGNATURE_SIZE as usize)?;
     let stored_header = common::read_exact(&mut file, 1584)?; //max header size

src/formats/epk2b/mod.rs

@@ -13,8 +13,8 @@ use include::*;
 pub fn is_epk2b_file(app_ctx: &AppContext) -> Result<Option<Box<dyn Any>>, Box<dyn std::error::Error>> {
     let file = match app_ctx.file() {Some(f) => f, None => return Ok(None)};
 
-    let epk2_magic = common::read_file(&file, 12, 4)?;
     let epak_magic = common::read_file(&file, 0, 4)?;
+    let epk2_magic = common::read_file(&file, 12, 4)?;    
     if epak_magic == b"epak" && epk2_magic == b"EPK2" {
         Ok(Some(Box::new(())))
     } else {

src/formats/epk3/mod.rs

@@ -4,7 +4,7 @@ use crate::AppContext;
 
 use std::fs::{self, OpenOptions};
 use std::path::Path;
-use std::io::{Write, Seek, SeekFrom, Cursor};
+use std::io::{Write, Cursor};
 use binrw::BinReaderExt;
 
 use crate::utils::common;
@@ -18,7 +18,7 @@ pub fn is_epk3_file(_app_ctx: &AppContext) -> Result<Option<Box<dyn Any>>, Box<d
 
 pub fn extract_epk3(app_ctx: &AppContext, _ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
     let mut file = app_ctx.file().ok_or("Extractor expected file")?;
-    file.seek(SeekFrom::Start(0))?;
+
     let stored_header = common::read_exact(&mut file, 1712)?;
     let header: Vec<u8>;
     let _header_signature;

src/formats/rvp/mod.rs

@@ -9,13 +9,16 @@ use std::io::{Write, Read, Cursor, Seek};
 use crate::utils::common;
 use include::*;
 
+pub struct RvpContext {
+    header_offset: u64,
+}
+
 pub fn is_rvp_file(app_ctx: &AppContext) -> Result<Option<Box<dyn Any>>, Box<dyn std::error::Error>> {
-    let mut file = match app_ctx.file() {Some(f) => f, None => return Ok(None)};
+    let file = match app_ctx.file() {Some(f) => f, None => return Ok(None)};
     //MVP
     let header = common::read_file(&file, 0, 4)?;
     if header == b"UPDT" {
-        file.seek(std::io::SeekFrom::Start(36))?; //skip rest of header // NOT GOOD PRACTICE SHOULD BE REMOVED
-        return Ok(Some(Box::new(())))
+        return Ok(Some(Box::new(RvpContext {header_offset: 36})))
     }
 
     //RVP
@@ -26,12 +29,14 @@ pub fn is_rvp_file(app_ctx: &AppContext) -> Result<Option<Box<dyn Any>>, Box<dyn
         }
     }
     
-    file.seek(std::io::SeekFrom::Start(64))?; //skip rest of header // NOT GOOD PRACTICE SHOULD BE REMOVED
-    Ok(Some(Box::new(())))
+    Ok(Some(Box::new(RvpContext {header_offset: 64})))
 }
 
-pub fn extract_rvp(app_ctx: &AppContext, _ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
+pub fn extract_rvp(app_ctx: &AppContext, ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
     let mut file = app_ctx.file().ok_or("Extractor expected file")?;
+    let ctx = ctx.downcast::<RvpContext>().expect("Missing context");
+
+    file.seek(std::io::SeekFrom::Start(ctx.header_offset))?;
 
     let mut obf_data = Vec::new();  //we sadly cannot deXOR on the fly because of its 32 byte pattern
     file.read_to_end(&mut obf_data)?;

src/formats/sddl_sec/mod.rs

@@ -66,7 +66,6 @@ fn parse_tdi_to_modules(tdi_data: Vec<u8>) -> Result<Vec<TdiTgtInf>, Box<dyn std
 
 pub fn extract_sddl_sec(app_ctx: &AppContext, _ctx: Box<dyn Any>) -> Result<(), Box<dyn std::error::Error>> {
     let mut file = app_ctx.file().ok_or("Extractor expected file")?;
-    file.seek(SeekFrom::Start(0))?;
     let mut secfile_hdr_reader = Cursor::new(decipher(&common::read_exact(&mut file, 32)?));
     let secfile_header: SecHeader = secfile_hdr_reader.read_be()?;