From f29bd5a65e9688222474e54b4f5d0fb127a23db3 Mon Sep 17 00:00:00 2001
From: Jared Hancock <jared.hancock@centeredsolutions.com>
Date: Sun, 19 Jan 2025 15:37:55 -0600
Subject: [PATCH] extmod/modlwip: Fix incorrect peer address for IPv6.

For IPv6 connections, the peer address was previously defined as only the
first four bytes of the IP address. For IPv6 addresses, this resulted in an
incorrect IPv4 address. For instance, receiving a packet via `::recvfrom`
from `'fe80::87:e7ff:fe48:629a'` is returned as having a peer address of
`'254.128.0.0'`

Signed-off-by: Jared Hancock <jared.hancock@centeredsolutions.com>
---
 extmod/modlwip.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/extmod/modlwip.c b/extmod/modlwip.c
index ce70627c3..bcccd363e 100644
--- a/extmod/modlwip.c
+++ b/extmod/modlwip.c
@@ -37,7 +37,6 @@
 
 #if MICROPY_PY_LWIP
 
-#include "shared/netutils/netutils.h"
 #include "modnetwork.h"
 
 #include "lwip/init.h"
@@ -308,7 +307,7 @@ typedef struct _lwip_socket_obj_t {
         } connection;
     } incoming;
     mp_obj_t callback;
-    byte peer[4];
+    ip_addr_t peer;
     mp_uint_t peer_port;
     mp_uint_t timeout;
     uint16_t recv_offset;
@@ -638,7 +637,7 @@ static mp_uint_t lwip_raw_udp_send(lwip_socket_obj_t *socket, const byte *buf, m
 }
 
 // Helper function for recv/recvfrom to handle raw/UDP packets
-static mp_uint_t lwip_raw_udp_receive(lwip_socket_obj_t *socket, byte *buf, mp_uint_t len, byte *ip, mp_uint_t *port, int *_errno) {
+static mp_uint_t lwip_raw_udp_receive(lwip_socket_obj_t *socket, byte *buf, mp_uint_t len, ip_addr_t *ip, mp_uint_t *port, int *_errno) {
 
     if (socket->incoming.pbuf == NULL) {
         if (socket->timeout == 0) {
@@ -1132,7 +1131,7 @@ static mp_obj_t lwip_socket_connect(mp_obj_t self_in, mp_obj_t addr_in) {
                 mp_raise_OSError(error_lookup_table[-err]);
             }
             socket->peer_port = (mp_uint_t)port;
-            memcpy(socket->peer, &dest, sizeof(socket->peer));
+            memcpy(&socket->peer, &dest, sizeof(socket->peer));
             MICROPY_PY_LWIP_EXIT
 
             // And now we wait...
@@ -1294,13 +1293,13 @@ static mp_obj_t lwip_socket_recvfrom(mp_obj_t self_in, mp_obj_t len_in) {
     mp_int_t len = mp_obj_get_int(len_in);
     vstr_t vstr;
     vstr_init_len(&vstr, len);
-    byte ip[4];
+    ip_addr_t ip;
     mp_uint_t port;
 
     mp_uint_t ret = 0;
     switch (socket->type) {
         case MOD_NETWORK_SOCK_STREAM: {
-            memcpy(ip, &socket->peer, sizeof(socket->peer));
+            memcpy(&ip, &socket->peer, sizeof(socket->peer));
             port = (mp_uint_t)socket->peer_port;
             ret = lwip_tcp_receive(socket, (byte *)vstr.buf, len, &_errno);
             break;
@@ -1309,7 +1308,7 @@ static mp_obj_t lwip_socket_recvfrom(mp_obj_t self_in, mp_obj_t len_in) {
         #if MICROPY_PY_LWIP_SOCK_RAW
         case MOD_NETWORK_SOCK_RAW:
         #endif
-            ret = lwip_raw_udp_receive(socket, (byte *)vstr.buf, len, ip, &port, &_errno);
+            ret = lwip_raw_udp_receive(socket, (byte *)vstr.buf, len, &ip, &port, &_errno);
             break;
     }
     if (ret == -1) {
@@ -1323,7 +1322,8 @@ static mp_obj_t lwip_socket_recvfrom(mp_obj_t self_in, mp_obj_t len_in) {
         vstr.len = ret;
         tuple[0] = mp_obj_new_bytes_from_vstr(&vstr);
     }
-    tuple[1] = netutils_format_inet_addr(ip, port, NETUTILS_BIG);
+    tuple[1] = lwip_format_inet_addr(&ip, port);
+
     return mp_obj_new_tuple(2, tuple);
 }
 static MP_DEFINE_CONST_FUN_OBJ_2(lwip_socket_recvfrom_obj, lwip_socket_recvfrom);