Replace memmove() emulation with copy_within()

Fixes #14
jedisct1 · Jan 19, 2021 · 4aa5d0f · 4aa5d0f
1 parent 9dc8b2a
commit 4aa5d0f
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Showing 2 changed files with 11 additions and 32 deletions.
diff --git a/src/parsed_packet.rs b/src/parsed_packet.rs
@@ -10,7 +10,6 @@ use crate::rr_iterator::*;
 use crate::synth::gen;
 use byteorder::{BigEndian, ByteOrder};
 use rand::prelude::*;
-use std::ptr;
 
 /// A `ParsedPacket` structure contains information about a successfully parsed
 /// DNS packet, that allows quick access to (extended) flags and to individual sections.
@@ -318,22 +317,16 @@ impl ParsedPacket {
             bail!(DSError::PacketTooLarge)
         }
         let insertion_offset = self.insertion_offset(section)?;
-        let new_len = self.packet().len() + rr_len;
+        let packet_len = self.packet().len();
+        let new_len = packet_len + rr_len;
         self.packet_mut().reserve(rr_len);
         if insertion_offset == new_len {
             self.packet_mut().extend_from_slice(&rr.packet);
         } else {
-            unsafe {
-                let packet_ptr = self.packet_mut().as_mut_ptr();
-                ptr::copy(
-                    packet_ptr.add(insertion_offset),
-                    packet_ptr.add(insertion_offset + rr_len),
-                    self.packet().len() - insertion_offset,
-                );
-                self.packet_mut().set_len(new_len);
-            }
-            self.packet_mut()[insertion_offset..insertion_offset + rr_len]
-                .copy_from_slice(&rr.packet);
+            let packet = self.packet_mut();
+            packet.resize(new_len, 0);
+            packet.copy_within(insertion_offset..packet_len, insertion_offset + rr_len);
+            packet[insertion_offset..insertion_offset + rr_len].copy_from_slice(&rr.packet);
         }
         self.rrcount_inc(section)?;
         match section {

diff --git a/src/rr_iterator.rs b/src/rr_iterator.rs
@@ -6,7 +6,6 @@ use crate::parsed_packet::*;
 use byteorder::{BigEndian, ByteOrder};
 use std::marker;
 use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};
-use std::ptr;
 
 /// Accessor to the raw packet data.
 /// `offset` is the offset to the current RR.
@@ -207,25 +206,12 @@ pub trait TypedIterable {
                     new_packet_len,
                     (offset as isize + shift) as usize + (packet_len - offset) as usize
                 );
-                unsafe {
-                    let packet_ptr = packet.as_mut_ptr();
-                    ptr::copy(
-                        packet_ptr.add(offset),
-                        packet_ptr.offset((offset as isize + shift) as isize),
-                        packet_len - offset,
-                    );
-                }
+                packet.copy_within(offset..offset + packet_len, offset + shift as usize);
             } else if shift < 0 {
-                assert!(packet_len >= (-shift) as usize);
-                unsafe {
-                    let packet_ptr = packet.as_mut_ptr();
-                    ptr::copy(
-                        packet_ptr.offset((offset as isize - shift) as isize),
-                        packet_ptr.add(offset),
-                        packet_len - (offset as isize - shift) as usize,
-                    );
-                }
-                packet.truncate((packet_len as isize + shift) as usize);
+                let shift = (-shift) as usize;
+                assert!(packet_len >= shift);
+                packet.copy_within(offset + shift.., offset);
+                packet.truncate(packet_len - shift);
             }
         }
         let new_offset_next = (self.offset_next() as isize + shift) as usize;