extmod/modlwip: Support IPv6.

With these changes IPv6 works on the rp2 port (and possibly others that use
the lwIP socket implementation).

Things that have been tested and work:
- Neighbour solicitation for v6 link local address.
- Ping of v6 link-local address.
- Receiving a SLAAC address via router advertisement.
- Ping a v6 address allocated via SLAAC.
- Perform an outgoing connection to a routed v6-address (via default
  gateway).
- Create a listening IPv6 wildcard socked bound to ::, and trying to access
  it via link-local, SLAAC, and IPv4 (to ensure the dual-stack binding
  works).

Things that could be improved:
- socket.socket().getaddrinfo only returns the v4 address.  It could also
  return v6 addresses (getaddrinfo is actively programmed to only return a
  single address, and this is the v4-address by default, with fallback to
  the v6 address if both are enabled).

Signed-off-by: Felix Dörre <felix@dogcraft.de>

1 files changed, 7 insertions, 7 deletions

diff --git a/shared/netutils/dhcpserver.c b/shared/netutils/dhcpserver.c
index dca95507d3..9a4d461a93 100644
--- a/shared/netutils/dhcpserver.c
+++ b/shared/netutils/dhcpserver.c
@@ -113,7 +113,7 @@ static void dhcp_socket_free(struct udp_pcb **udp) {
 
 static int dhcp_socket_bind(struct udp_pcb **udp, uint32_t ip, uint16_t port) {
     ip_addr_t addr;
-    IP4_ADDR(&addr, ip >> 24 & 0xff, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff);
+    IP_ADDR4(&addr, ip >> 24 & 0xff, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff);
     // TODO convert lwIP errors to errno
     return udp_bind(*udp, &addr, port);
 }
@@ -131,7 +131,7 @@ static int dhcp_socket_sendto(struct udp_pcb **udp, struct netif *netif, const v
     memcpy(p->payload, buf, len);
 
     ip_addr_t dest;
-    IP4_ADDR(&dest, ip >> 24 & 0xff, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff);
+    IP_ADDR4(&dest, ip >> 24 & 0xff, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff);
     err_t err;
     if (netif != NULL) {
         err = udp_sendto_if(*udp, p, &dest, port, netif);
@@ -205,7 +205,7 @@ static void dhcp_server_process(void *arg, struct udp_pcb *upcb, struct pbuf *p,
     }
 
     dhcp_msg.op = DHCPOFFER;
-    memcpy(&dhcp_msg.yiaddr, &d->ip.addr, 4);
+    memcpy(&dhcp_msg.yiaddr, &ip_2_ip4(&d->ip)->addr, 4);
 
     uint8_t *opt = (uint8_t *)&dhcp_msg.options;
     opt += 4; // assume magic cookie: 99, 130, 83, 99
@@ -248,7 +248,7 @@ static void dhcp_server_process(void *arg, struct udp_pcb *upcb, struct pbuf *p,
                 // Should be NACK
                 goto ignore_request;
             }
-            if (memcmp(o + 2, &d->ip.addr, 3) != 0) {
+            if (memcmp(o + 2, &ip_2_ip4(&d->ip)->addr, 3) != 0) {
                 // Should be NACK
                 goto ignore_request;
             }
@@ -280,9 +280,9 @@ static void dhcp_server_process(void *arg, struct udp_pcb *upcb, struct pbuf *p,
             goto ignore_request;
     }
 
-    opt_write_n(&opt, DHCP_OPT_SERVER_ID, 4, &d->ip.addr);
-    opt_write_n(&opt, DHCP_OPT_SUBNET_MASK, 4, &d->nm.addr);
-    opt_write_n(&opt, DHCP_OPT_ROUTER, 4, &d->ip.addr); // aka gateway; can have multiple addresses
+    opt_write_n(&opt, DHCP_OPT_SERVER_ID, 4, &ip_2_ip4(&d->ip)->addr);
+    opt_write_n(&opt, DHCP_OPT_SUBNET_MASK, 4, &ip_2_ip4(&d->nm)->addr);
+    opt_write_n(&opt, DHCP_OPT_ROUTER, 4, &ip_2_ip4(&d->ip)->addr); // aka gateway; can have multiple addresses
     opt_write_u32(&opt, DHCP_OPT_DNS, DEFAULT_DNS); // can have multiple addresses
     opt_write_u32(&opt, DHCP_OPT_IP_LEASE_TIME, DEFAULT_LEASE_TIME_S);
     *opt++ = DHCP_OPT_END;