Spanify production code in services/network/p2p/

This largely involves migrating to the newer span-based net::IOBuffer
APIs.

Bug: 351564777
Change-Id: I88e9717ba51593e18d11f070b2ac9210a8dda01b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6506171
Commit-Queue: Harald Alvestrand <hta@chromium.org>
Reviewed-by: Harald Alvestrand <hta@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1456966}

services/network/p2p/socket_manager.cc

@@ -2,11 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifdef UNSAFE_BUFFERS_BUILD
-// TODO(crbug.com/351564777): Remove this and convert code to safer constructs.
-#pragma allow_unsafe_buffers
-#endif
-
 #include "services/network/p2p/socket_manager.h"
 
 #include <stddef.h>
@@ -270,8 +265,8 @@ void P2PSocketManager::DumpPacket(base::span<const uint8_t> packet,
     NOTREACHED();
   }
 
-  std::vector<uint8_t> header_buffer(rtp_packet.data(),
-                                     rtp_packet.data() + header_size);
+  std::vector<uint8_t> header_buffer(rtp_packet.begin(),
+                                     rtp_packet.begin() + header_size);
   trusted_socket_manager_client_->DumpPacket(header_buffer, rtp_packet.size(),
                                              incoming);
 }

services/network/p2p/socket_tcp.cc

@@ -2,16 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifdef UNSAFE_BUFFERS_BUILD
-// TODO(crbug.com/351564777): Remove this and convert code to safer constructs.
-#pragma allow_unsafe_buffers
-#endif
-
 #include "services/network/p2p/socket_tcp.h"
 
 #include <stddef.h>
 
 #include <utility>
+#include <vector>
 
 #include "base/containers/span.h"
 #include "base/containers/span_writer.h"
@@ -466,9 +462,10 @@ void P2PSocketTcp::DoSend(const net::IPEndPoint& to,
     CHECK_EQ(writer.remaining(), 0u);
   }
 
-  webrtc::ApplyPacketOptions(
-      send_buffer.buffer->bytes() + kPacketHeaderSize,
-      send_buffer.buffer->BytesRemaining() - kPacketHeaderSize,
+  base::span<uint8_t> send_buffer_without_header =
+      send_buffer.buffer->span().subspan(kPacketHeaderSize);
+  webrtc::ApplyPacketOptions(send_buffer_without_header.data(),
+                             send_buffer_without_header.size(),
                              options.packet_time_params, webrtc::TimeMicros());
 
   WriteOrQueue(send_buffer);
@@ -527,28 +524,25 @@ void P2PSocketStunTcp::DoSend(const net::IPEndPoint& to,
 
   // Add any pad bytes to the total size.
   int buffer_size = data.size() + pad_bytes;
+  std::vector<uint8_t> buffer;
+  buffer.reserve(buffer_size);
+  buffer.assign(data.begin(), data.end());
+  if (pad_bytes) {
+    DCHECK_LE(pad_bytes, 4);
+    buffer.insert(buffer.end(), pad_bytes, 0);
+  }
 
   SendBuffer send_buffer(
       options.packet_id,
       base::MakeRefCounted<net::DrainableIOBuffer>(
-          base::MakeRefCounted<net::IOBufferWithSize>(buffer_size),
+          base::MakeRefCounted<net::VectorIOBuffer>(std::move(buffer)),
           buffer_size));
-  memcpy(send_buffer.buffer->data(), data.data(), data.size());
 
   webrtc::ApplyPacketOptions(send_buffer.buffer->bytes(), data.size(),
                              options.packet_time_params, webrtc::TimeMicros());
 
-  if (pad_bytes) {
-    char padding[4] = {};
-    DCHECK_LE(pad_bytes, 4);
-    memcpy(send_buffer.buffer->data() + data.size(), padding, pad_bytes);
-  }
-
   // WriteOrQueue may free the memory, so dump it first.
-  delegate_->DumpPacket(
-      base::span(reinterpret_cast<const uint8_t*>(send_buffer.buffer->data()),
-                 data.size()),
-      false);
+  delegate_->DumpPacket(send_buffer.buffer->span(), false);
 
   WriteOrQueue(send_buffer);
 }

services/network/p2p/socket_udp.cc

@@ -2,11 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifdef UNSAFE_BUFFERS_BUILD
-// TODO(crbug.com/351564777): Remove this and convert code to safer constructs.
-#pragma allow_unsafe_buffers
-#endif
-
 #include "services/network/p2p/socket_udp.h"
 
 #include <tuple>
@@ -115,12 +110,10 @@ P2PPendingPacket::P2PPendingPacket(
     const webrtc::AsyncSocketPacketOptions& options,
     uint64_t id)
     : to(to),
-      data(base::MakeRefCounted<net::IOBufferWithSize>(content.size())),
+      data(base::MakeRefCounted<net::VectorIOBuffer>(content)),
       size(content.size()),
       packet_options(options),
-      id(id) {
-  memcpy(data->data(), content.data(), content.size());
-}
+      id(id) {}
 
 P2PPendingPacket::P2PPendingPacket(const P2PPendingPacket& other) = default;
 P2PPendingPacket::~P2PPendingPacket() = default;
@@ -298,9 +291,7 @@ void P2PSocketUdp::MaybeDrainReceivedPackets(bool force) {
 
 bool P2PSocketUdp::HandleReadResult(int result) {
   if (result > 0) {
-    auto data =
-        base::span(reinterpret_cast<const uint8_t*>(recv_buffer_->data()),
-                   static_cast<size_t>(result));
+    auto data = recv_buffer_->first(static_cast<size_t>(result));
 
     if (!base::Contains(connected_peers_, recv_address_)) {
       P2PSocket::StunMessageType type;
@@ -364,10 +355,7 @@ bool P2PSocketUdp::DoSend(const P2PPendingPacket& packet) {
   // messages are sent in correct order.
   if (!base::Contains(connected_peers_, packet.to)) {
     P2PSocket::StunMessageType type = P2PSocket::StunMessageType();
-    bool stun = GetStunPacketType(
-        base::span(reinterpret_cast<const uint8_t*>(packet.data->data()),
-                   packet.size),
-        &type);
+    bool stun = GetStunPacketType(packet.data->first(packet.size), &type);
     if (!stun || type == STUN_DATA_INDICATION) {
       LOG(ERROR) << "Page tried to send a data packet to "
                  << packet.to.ToString() << " before STUN binding is finished.";
@@ -437,10 +425,7 @@ bool P2PSocketUdp::DoSend(const P2PPendingPacket& packet) {
     }
   }
 
-  delegate_->DumpPacket(
-      base::span(reinterpret_cast<const uint8_t*>(packet.data->data()),
-                 packet.size),
-      false);
+  delegate_->DumpPacket(packet.data->first(packet.size), false);
 
   return true;
 }