Gzip support for inflate

fuzz/fuzz_targets/end_to_end.rs

@@ -10,7 +10,7 @@ use std::ffi::{c_char, c_int, c_uint};
 fuzz_target!(|input: (String, DeflateConfig)| {
     let (data, config) = input;
 
-    if !(0..=15).contains(&config.window_bits) {
+    if !(0..32).contains(&config.window_bits) {
         // lower is raw, higher is gzip
         return;
     }

libz-rs-sys/src/lib.rs

@@ -199,9 +199,20 @@ pub unsafe extern "C" fn inflateSetDictionary(
     zlib_rs::inflate::set_dictionary(stream, dict) as _
 }
 
-// pub unsafe extern "C" fn inflateGetHeader(strm: z_streamp, head: gz_headerp) -> c_int {
-//     todo!("part of gzip support")
-// }
+// part of gzip
+pub unsafe extern "C" fn inflateGetHeader(strm: z_streamp, head: gz_headerp) -> c_int {
+    if let Some(stream) = InflateStream::from_stream_mut(strm) {
+        let header = if head.is_null() {
+            None
+        } else {
+            Some(unsafe { &mut *(head) })
+        };
+
+        zlib_rs::inflate::get_header(stream, header) as i32
+    } else {
+        ReturnCode::StreamError as _
+    }
+}
 
 // undocumented but exposed function
 pub unsafe extern "C" fn inflateUndermine(strm: *mut z_stream, subvert: i32) -> c_int {

libz-rs-sys/src/tests/inflate.rs

@@ -2,9 +2,11 @@ use std::mem::ManuallyDrop;
 
 use crate as libz_rs_sys;
 
-use std::ffi::{c_char, c_int, c_void};
+use std::ffi::{c_char, c_int, c_void, CStr};
 
 use libz_rs_sys::*;
+use zlib_rs::deflate::compress_slice;
+use zlib_rs::inflate::{uncompress_slice, INFLATE_STATE_SIZE};
 use zlib_rs::{Flush, MAX_WBITS};
 
 const VERSION: *const c_char = "2.3.0\0".as_ptr() as *const c_char;
@@ -181,8 +183,31 @@ fn inf(input: &[u8], _what: &str, step: usize, win: i32, len: usize, err: c_int)
 
     let mut out = vec![0u8; len];
 
+    let extra: [u8; 1024] = [0; 1024];
+    let name: [u8; 64] = [0; 64];
+    let comment: [u8; 64] = [0; 64];
+
+    // Set header
+    // See: https://www.zlib.net/manual.html
+    let mut header = gz_header {
+        text: 0,
+        time: 0,
+        xflags: 0,
+        os: 0,
+        extra: extra.as_ptr() as *mut u8,
+        extra_len: 0,
+        extra_max: 1024,
+        name: name.as_ptr() as *mut u8,
+        name_max: 64, // How / where should this be set?
+        comment: comment.as_ptr() as *mut u8,
+        comm_max: 64,
+        hcrc: 0,
+        done: 0,
+    };
+
     if win == 47 {
-        todo!("gzip")
+        let err = unsafe { inflateGetHeader(&mut stream, &mut header) };
+        assert_eq!(ReturnCode::from(err), ReturnCode::Ok);
     }
 
     let mut have = input.len();
@@ -199,7 +224,9 @@ fn inf(input: &[u8], _what: &str, step: usize, win: i32, len: usize, err: c_int)
         let ret = unsafe { inflate(&mut stream, Flush::NoFlush as _) };
 
         if let Some(err) = err {
-            assert_eq!(ret, err)
+            if err != 9 {
+                assert_eq!(ret, err)
+            }
         }
 
         if !matches!(ret, Z_OK | Z_BUF_ERROR | Z_NEED_DICT) {
@@ -320,7 +347,7 @@ fn cover_wrap() {
 
     // ------------------------------
 
-    let size = 2 * zlib_rs::inflate::INFLATE_STATE_SIZE + 256;
+    let size = 2 * INFLATE_STATE_SIZE + 256;
     mem_limit(&mut strm, size);
 
     ret = unsafe { inflatePrime(&mut strm, 16, 0) };
@@ -402,7 +429,6 @@ fn check_adler32() {
     )
 }
 #[test]
-#[ignore = "gzip"]
 fn bad_header_crc() {
     inf(
         &[
@@ -417,7 +443,6 @@ fn bad_header_crc() {
 }
 
 #[test]
-#[ignore = "gzip"]
 fn check_gzip_length() {
     inf(
         &[
@@ -433,7 +458,6 @@ fn check_gzip_length() {
 }
 
 #[test]
-#[ignore = "gzip"]
 fn bad_zlib_header_check() {
     inf(
         &[0x78, 0x90],
@@ -814,7 +838,6 @@ fn copy_direct_from_output() {
 }
 
 #[test]
-#[ignore = "gzip"]
 fn cover_cve_2022_37434() {
     inf(
         &[
@@ -1070,3 +1093,195 @@ fn inflate_adler() {
     let length = Ord::min(stream.total_out as usize, ORIGINAL.len());
     assert_eq!(&uncompressed[..length], &ORIGINAL.as_bytes()[..length])
 }
+
+#[test]
+fn inflate_get_header_non_gzip_stream() {
+    let mut stream = mem_setup();
+
+    let win = 15; // i.e. zlib compression (and not gzip)
+    let init_err = unsafe { inflateInit2_(&mut stream, win, VERSION, STREAM_SIZE) };
+    if init_err != Z_OK {
+        mem_done(&mut stream);
+        return;
+    }
+
+    let mut header = gz_header::default();
+
+    assert_eq!(
+        unsafe { inflateGetHeader(&mut stream, &mut header) },
+        ReturnCode::StreamError as i32
+    );
+}
+
+#[test]
+fn inflate_window_bits_0_is_15() {
+    let input = b"Hello World!\n";
+
+    let mut compressed = [0; 64];
+    let (compressed, err) = compress_slice(&mut compressed, input, DeflateConfig::new(6));
+    assert_eq!(err, ReturnCode::Ok);
+
+    let config = InflateConfig { window_bits: 15 };
+    let mut output_15 = [0; 64];
+    let (output_15, err) = uncompress_slice(&mut output_15, compressed, config);
+    assert_eq!(err, ReturnCode::Ok);
+
+    let config = InflateConfig { window_bits: 0 };
+    let mut output_0 = [0; 64];
+    let (output_0, err) = uncompress_slice(&mut output_0, compressed, config);
+    assert_eq!(err, ReturnCode::Ok);
+
+    // for window size 0, the default of 15 is picked
+    // NOTE: the window size does not actually influence
+    // the output for an input this small.
+    assert_eq!(output_15, output_0);
+
+    assert_eq!(output_15, input);
+}
+
+#[test]
+fn gzip_chunked() {
+    let input = b"Hello World\n";
+
+    let extra =
+        "Scheduling and executing async tasks is a job handled by an async runtime, such as\0";
+    let name =
+        "tokio, async-std, and smol. You’ve probably used them at some point, either directly or\0";
+    let comment =
+        "indirectly. They, along with many frameworks that require async, do their best to hide\0";
+
+    let config = DeflateConfig {
+        window_bits: 31,
+        ..Default::default()
+    };
+
+    let mut stream = MaybeUninit::<libz_rs_sys::z_stream>::zeroed();
+
+    const VERSION: *const c_char = "2.1.4\0".as_ptr() as *const c_char;
+    const STREAM_SIZE: c_int = std::mem::size_of::<libz_rs_sys::z_stream>() as c_int;
+
+    let err = unsafe {
+        libz_rs_sys::deflateInit2_(
+            stream.as_mut_ptr(),
+            config.level,
+            config.method as i32,
+            config.window_bits,
+            config.mem_level,
+            config.strategy as i32,
+            VERSION,
+            STREAM_SIZE,
+        )
+    };
+    assert_eq!(err, 0);
+
+    let stream = unsafe { stream.assume_init_mut() };
+
+    let mut header = libz_rs_sys::gz_header {
+        text: 0,
+        time: 0,
+        xflags: 0,
+        os: 0,
+        extra: extra.as_ptr() as *mut _,
+        extra_len: extra.len() as _,
+        extra_max: 0,
+        name: name.as_ptr() as *mut _,
+        name_max: 0,
+        comment: comment.as_ptr() as *mut _,
+        comm_max: 0,
+        hcrc: 1,
+        done: 0,
+    };
+
+    let err = unsafe { libz_rs_sys::deflateSetHeader(stream, &mut header) };
+    assert_eq!(err, 0);
+
+    stream.next_in = input.as_ptr() as *mut _;
+    stream.avail_in = input.len() as _;
+
+    let mut output_rs = [0u8; 512];
+    stream.next_out = output_rs.as_mut_ptr();
+    stream.avail_out = output_rs.len() as _;
+
+    let err = unsafe { libz_rs_sys::deflate(stream, Flush::Finish as _) };
+    assert_eq!(err, ReturnCode::StreamEnd as i32);
+
+    let output_rs = &mut output_rs[..stream.total_out as usize];
+
+    let err = unsafe { libz_rs_sys::deflateEnd(stream) };
+    assert_eq!(err, 0);
+
+    {
+        let mut stream = MaybeUninit::<libz_rs_sys::z_stream>::zeroed();
+
+        const VERSION: *const c_char = "2.1.4\0".as_ptr() as *const c_char;
+        const STREAM_SIZE: c_int = std::mem::size_of::<libz_rs_sys::z_stream>() as c_int;
+
+        let err = unsafe {
+            libz_rs_sys::inflateInit2_(
+                stream.as_mut_ptr(),
+                config.window_bits,
+                VERSION,
+                STREAM_SIZE,
+            )
+        };
+        assert_eq!(err, 0);
+
+        let stream = unsafe { stream.assume_init_mut() };
+
+        stream.next_in = output_rs.as_mut_ptr() as _;
+        stream.avail_in = output_rs.len() as _;
+
+        let mut output = [0u8; 64];
+        stream.next_out = output.as_mut_ptr();
+        stream.avail_out = output.len() as _;
+
+        let mut extra_buf = [0u8; 64];
+        let mut name_buf = [0u8; 64];
+        let mut comment_buf = [0u8; 256];
+
+        let mut header = libz_rs_sys::gz_header {
+            text: 0,
+            time: 0,
+            xflags: 0,
+            os: 0,
+            extra: extra_buf.as_mut_ptr(),
+            extra_len: 0,
+            extra_max: extra_buf.len() as _,
+            name: name_buf.as_mut_ptr(),
+            name_max: name_buf.len() as _,
+            comment: comment_buf.as_mut_ptr(),
+            comm_max: comment_buf.len() as _,
+            hcrc: 0,
+            done: 0,
+        };
+
+        let err = unsafe { libz_rs_sys::inflateGetHeader(stream, &mut header) };
+        assert_eq!(err, 0);
+
+        let err = unsafe { libz_rs_sys::inflate(stream, Flush::NoFlush as _) };
+        assert_eq!(err, ReturnCode::StreamEnd as i32);
+
+        let err = unsafe { libz_rs_sys::inflateEnd(stream) };
+        assert_eq!(err, ReturnCode::Ok as i32);
+
+        assert!(!header.extra.is_null());
+        assert_eq!(
+            std::str::from_utf8(&extra_buf).unwrap(),
+            &extra[..extra_buf.len()]
+        );
+
+        assert!(!header.name.is_null());
+        assert_eq!(
+            std::str::from_utf8(&name_buf).unwrap(),
+            &name[..name_buf.len()]
+        );
+
+        assert!(!header.comment.is_null());
+        assert_eq!(
+            unsafe { CStr::from_ptr(comment_buf.as_ptr().cast()) }
+                .to_str()
+                .unwrap(),
+            comment.trim_end_matches('\0')
+        );
+    }
+}

load-dynamic-libz-ng/src/lib.rs

@@ -90,7 +90,7 @@ pub unsafe fn compress(
     f(dest, destLen, source, sourceLen)
 }
 
-unsafe fn deflate(strm: *mut libz_ng_sys::z_stream, flush: i32) -> std::ffi::c_int {
+pub unsafe fn deflate(strm: *mut libz_ng_sys::z_stream, flush: i32) -> std::ffi::c_int {
     const LIBZ_NG_SO: &str = "/home/folkertdev/rust/zlib-ng/libz-ng.so";
 
     let lib = libloading::Library::new(LIBZ_NG_SO).unwrap();

zlib-rs/src/c_api.rs

@@ -160,6 +160,26 @@ pub struct gz_header {
     pub done: i32,
 }
 
+impl Default for gz_header {
+    fn default() -> Self {
+        Self {
+            text: 0,
+            time: 0,
+            xflags: 0,
+            os: 0,
+            extra: std::ptr::null_mut(),
+            extra_len: 0,
+            extra_max: 0,
+            name: std::ptr::null_mut(),
+            name_max: 0,
+            comment: std::ptr::null_mut(),
+            comm_max: 0,
+            hcrc: 0,
+            done: 0,
+        }
+    }
+}
+
 impl gz_header {
     // based on the spec https://www.ietf.org/rfc/rfc1952.txt
     //