http2: follow range requests

Move the content-range parsing code to rust

rules/http2-events.rules

@@ -15,3 +15,4 @@ alert http2 any any -> any any (msg:"SURICATA HTTP2 too long frame data"; flow:e
 alert http2 any any -> any any (msg:"SURICATA HTTP2 stream identifier reuse"; flow:established; app-layer-event:http2.stream_id_reuse; classtype:protocol-command-decode; sid:2290007; rev:1;)
 alert http2 any any -> any any (msg:"SURICATA HTTP2 invalid HTTP1 settings during upgrade"; flow:established; app-layer-event:http2.invalid_http1_settings; classtype:protocol-command-decode; sid:2290008; rev:1;)
 alert http2 any any -> any any (msg:"SURICATA HTTP2 failed decompression"; flow:established; app-layer-event:http2.failed_decompression; classtype:protocol-command-decode; sid:2290009; rev:1;)
+alert http2 any any -> any any (msg:"SURICATA HTTP2 invalid range header"; flow:established; app-layer-event:http2.invalid_range; classtype:protocol-command-decode; sid:2290010; rev:1;)

rust/cbindgen.toml

@@ -87,6 +87,8 @@ exclude = [
     "CLuaState",
     "DetectEngineState",
     "Flow",
+    "StreamingBufferConfig",
+    "HttpRangeContainerBlock",
     "FileContainer",
     "JsonT",
     "IKEState",

rust/src/core.rs

@@ -99,6 +99,17 @@ pub type AppLayerDecoderEventsFreeEventsFunc =
 
 pub enum StreamingBufferConfig {}
 
+// Opaque flow type (defined in C)
+pub enum HttpRangeContainerBlock {}
+
+pub type SCHttpRangeFreeBlock = extern "C" fn (
+        c: *mut HttpRangeContainerBlock);
+pub type SCHTPFileCloseHandleRange = extern "C" fn (
+        fc: *mut FileContainer,
+        flags: u16,
+        c: *mut HttpRangeContainerBlock,
+        data: *const u8,
+        data_len: u32);
 pub type SCFileOpenFileWithId = extern "C" fn (
         file_container: &FileContainer,
         sbcfg: &StreamingBufferConfig,
@@ -144,6 +155,9 @@ pub struct SuricataContext {
     AppLayerDecoderEventsFreeEvents: AppLayerDecoderEventsFreeEventsFunc,
     pub AppLayerParserTriggerRawStreamReassembly: AppLayerParserTriggerRawStreamReassemblyFunc,
 
+    pub HttpRangeFreeBlock: SCHttpRangeFreeBlock,
+    pub HTPFileCloseHandleRange: SCHTPFileCloseHandleRange,
+
     pub FileOpenFile: SCFileOpenFileWithId,
     pub FileCloseFile: SCFileCloseFileById,
     pub FileAppendData: SCFileAppendDataById,

rust/src/http2/detect.rs

@@ -484,6 +484,44 @@ fn http2_frames_get_header_firstvalue<'a>(
     return Err(());
 }
 
+// same as http2_frames_get_header_value but returns a new Vec
+// instead of using the transation to store the result slice
+pub fn http2_frames_get_header_value_vec(
+    tx: &HTTP2Transaction, direction: u8, name: &str,
+) -> Result<Vec<u8>, ()> {
+    let mut found = 0;
+    let mut vec = Vec::new();
+    let frames = if direction == STREAM_TOSERVER {
+        &tx.frames_ts
+    } else {
+        &tx.frames_tc
+    };
+    for i in 0..frames.len() {
+        if let Some(blocks) = http2_header_blocks(&frames[i]) {
+            for block in blocks.iter() {
+                if block.name == name.as_bytes().to_vec() {
+                    if found == 0 {
+                        vec.extend_from_slice(&block.value);
+                        found = 1;
+                    } else if found == 1 {
+                        vec.extend_from_slice(&[b',', b' ']);
+                        vec.extend_from_slice(&block.value);
+                        found = 2;
+                    } else {
+                        vec.extend_from_slice(&[b',', b' ']);
+                        vec.extend_from_slice(&block.value);
+                    }
+                }
+            }
+        }
+    }
+    if found == 0 {
+        return Err(());
+    } else {
+        return Ok(vec);
+    }
+}
+
 fn http2_frames_get_header_value<'a>(
     tx: &'a mut HTTP2Transaction, direction: u8, name: &str,
 ) -> Result<&'a [u8], ()> {

rust/src/http2/http2.rs

@@ -16,11 +16,14 @@
  */
 
 use super::decompression;
+use super::detect;
 use super::parser;
+use super::range;
+
 use crate::applayer::{self, *};
 use crate::core::{
-    self, AppProto, Flow, SuricataFileContext, ALPROTO_FAILED, ALPROTO_UNKNOWN, IPPROTO_TCP,
-    STREAM_TOCLIENT, STREAM_TOSERVER,
+    self, AppProto, Flow, HttpRangeContainerBlock, SuricataFileContext, ALPROTO_FAILED,
+    ALPROTO_UNKNOWN, IPPROTO_TCP, SC, STREAM_TOCLIENT, STREAM_TOSERVER,
 };
 use crate::filecontainer::*;
 use crate::filetracker::*;
@@ -129,11 +132,12 @@ pub struct HTTP2Transaction {
     pub frames_ts: Vec<HTTP2Frame>,
 
     decoder: decompression::HTTP2Decoder,
+    pub file_range: *mut HttpRangeContainerBlock,
 
     de_state: Option<*mut core::DetectEngineState>,
     events: *mut core::AppLayerDecoderEvents,
     tx_data: AppLayerTxData,
-    ft_tc: FileTransferTracker,
+    pub ft_tc: FileTransferTracker,
     ft_ts: FileTransferTracker,
 
     //temporary escaped header for detection
@@ -151,6 +155,7 @@ impl HTTP2Transaction {
             frames_tc: Vec::new(),
             frames_ts: Vec::new(),
             decoder: decompression::HTTP2Decoder::new(),
+            file_range: std::ptr::null_mut(),
             de_state: None,
             events: std::ptr::null_mut(),
             tx_data: AppLayerTxData::new(),
@@ -167,6 +172,27 @@ impl HTTP2Transaction {
         if let Some(state) = self.de_state {
             core::sc_detect_engine_state_free(state);
         }
+        if self.file_range != std::ptr::null_mut() {
+            match unsafe { SC } {
+                None => panic!("BUG no suricata_config"),
+                Some(c) => {
+                    //TODO get a file container instead of NULL
+                    (c.HTPFileCloseHandleRange)(
+                        std::ptr::null_mut(),
+                        0,
+                        self.file_range,
+                        std::ptr::null_mut(),
+                        0,
+                    );
+                    (c.HttpRangeFreeBlock)(self.file_range);
+                }
+            }
+        }
+    }
+
+    pub fn set_event(&mut self, event: HTTP2Event) {
+        let ev = event as u8;
+        core::sc_app_layer_decoder_events_set_event_raw(&mut self.events, ev);
     }
 
     fn handle_headers(&mut self, blocks: &Vec<parser::HTTP2FrameHeaderBlock>, dir: u8) {
@@ -179,7 +205,7 @@ impl HTTP2Transaction {
 
     fn decompress<'a>(
         &'a mut self, input: &'a [u8], dir: u8, sfcm: &'static SuricataFileContext, over: bool,
-        files: &mut FileContainer, flags: u16,
+        files: &mut FileContainer, flags: u16, flow: *const Flow,
     ) -> io::Result<()> {
         let mut output = Vec::with_capacity(decompression::HTTP2_DECOMPRESSION_CHUNK_SIZE);
         let decompressed = self.decoder.decompress(input, &mut output, dir)?;
@@ -190,6 +216,31 @@ impl HTTP2Transaction {
                 // we are now sure that new_chunk will open a file
                 // even if it may close it right afterwards
                 self.tx_data.incr_files_opened();
+                if let Ok(value) = detect::http2_frames_get_header_value_vec(
+                    self,
+                    STREAM_TOCLIENT,
+                    "content-range",
+                ) {
+                    match range::http2_parse_content_range(&value) {
+                        Ok((_, v)) => {
+                            range::http2_range_open(self, &v, flow, sfcm, flags, decompressed);
+                            if over {
+                                range::http2_range_close(self, files, flags, &[])
+                            }
+                        }
+                        _ => {
+                            self.set_event(HTTP2Event::InvalidRange);
+                        }
+                    }
+                }
+            } else {
+                if self.file_range != std::ptr::null_mut() {
+                    if over {
+                        range::http2_range_close(self, files, flags, decompressed)
+                    } else {
+                        range::http2_range_append(self.file_range, decompressed)
+                    }
+                }
             }
             self.ft_tc.new_chunk(
                 sfcm,
@@ -321,6 +372,7 @@ pub enum HTTP2Event {
     StreamIdReuse,
     InvalidHTTP1Settings,
     FailedDecompression,
+    InvalidRange,
 }
 
 pub struct HTTP2DynTable {
@@ -350,6 +402,7 @@ pub struct HTTP2State {
     transactions: Vec<HTTP2Transaction>,
     progress: HTTP2ConnectionState,
     pub files: Files,
+    flow: *const Flow,
 }
 
 impl HTTP2State {
@@ -366,6 +419,7 @@ impl HTTP2State {
             transactions: Vec::new(),
             progress: HTTP2ConnectionState::Http2StateInit,
             files: Files::default(),
+            flow: std::ptr::null_mut(),
         }
     }
 
@@ -825,6 +879,7 @@ impl HTTP2State {
                                         over,
                                         files,
                                         flags,
+                                        self.flow,
                                     ) {
                                         Err(_e) => {
                                             self.set_event(HTTP2Event::FailedDecompression);
@@ -1025,6 +1080,7 @@ pub unsafe extern "C" fn rs_http2_parse_ts(
 
     state.files.flags_ts = FileFlowToFlags(flow, STREAM_TOSERVER);
     state.files.flags_ts = state.files.flags_ts | FILE_USE_DETECT;
+    state.flow = flow;
     return state.parse_ts(buf);
 }
 
@@ -1037,6 +1093,7 @@ pub unsafe extern "C" fn rs_http2_parse_tc(
     let buf = build_slice!(input, input_len as usize);
     state.files.flags_tc = FileFlowToFlags(flow, STREAM_TOCLIENT);
     state.files.flags_tc = state.files.flags_tc | FILE_USE_DETECT;
+    state.flow = flow;
     return state.parse_tc(buf);
 }
 

rust/src/http2/mod.rs

@@ -21,3 +21,4 @@ pub mod http2;
 mod huffman;
 pub mod logger;
 mod parser;
+mod range;