1 files changed, 62 insertions, 0 deletions
diff --git a/fs-tracer-ebpf/src/syscalls/write.rs b/fs-tracer-ebpf/src/syscalls/write.rs
new file mode 100644
index 0000000..b204b45
--- /dev/null
+++ b/fs-tracer-ebpf/src/syscalls/write.rs
@@ -0,0 +1,62 @@
+use crate::*;
+
+pub fn handle_sys_write(ctx: TracePointContext, syscall_type: SyscallType) -> Result<u32, u32> {
+    match syscall_type {
+        SyscallType::Enter => unsafe { handle_sys_write_enter(ctx) },
+        SyscallType::Exit => unsafe { handle_sys_write_exit(ctx) },
+    }
+}
+
+unsafe fn handle_sys_write_enter(ctx: TracePointContext) -> Result<u32, u32> {
+    // info!(&ctx, "handle_sys_write start");
+    #[derive(Clone, Copy)]
+    struct WriteSyscallArgs {
+        fd: u64,
+        buf: *const u8,
+        count: u64,
+    }
+    let args = *ptr_at::<WriteSyscallArgs>(&ctx, 16).unwrap_unchecked();
+
+    // if fd is stdout, stderr or stdin, ignore
+    if args.fd <= 2 {
+        return Ok(0);
+    }
+
+    let mut buf = [0u8; 96]; //we need to make this muuuuuch bigger, we could use some sync with a bpf ds
+    let _ = bpf_probe_read_user_str_bytes(args.buf, &mut buf);
+    let buf_ref = &buf;
+
+    let mut anotherbuf = [0u8; 96];
+    let _ = bpf_probe_read_kernel_str_bytes(buf_ref.as_ptr(), &mut anotherbuf);
+
+    let tgid: u32 = ctx.tgid();
+    let _ = SYSCALL_ENTERS.insert(
+        &tgid,
+        &SyscallInfo::Write(WriteSyscallBPF {
+            pid: ctx.pid(),
+            fd: args.fd,
+            buf: anotherbuf,
+            count: args.count,
+            ret: -9999,
+        }),
+        0,
+    );
+
+    Ok(0)
+}
+
+unsafe fn handle_sys_write_exit(ctx: TracePointContext) -> Result<u32, u32> {
+    //info!(&ctx, "handle_sys_write_exit start");
+    let ret = *ptr_at::<i64>(&ctx, 16).unwrap_unchecked(); //TODO: We cant use unwrap, thats why we couldnt use the aya helper fns
+
+    let tgid = ctx.tgid();
+    if let Some(syscall) = SYSCALL_ENTERS.get(&tgid) {
+        let SyscallInfo::Write(mut syscall_write) = syscall;
+        syscall_write.ret = ret;
+        EVENTS.output(&ctx, &SyscallInfo::Write(syscall_write), 0);
+        let _ = SYSCALL_ENTERS.remove(&tgid);
+        return Ok(0);
+    }
+
+    Err(0)
+}