From 584c495d3201bbf01190cff673533bc405cee53f Mon Sep 17 00:00:00 2001 From: Peter Harper Date: Fri, 22 Sep 2023 18:46:08 +0530 Subject: [PATCH] shared/netutils/dhcpserver: Reply on correct netif. The DHCP server broadcasts messages. They are being sent via the default netif which might be completely the wrong network. We want to send messages to the netif we got the original message from. Original author: [Peter Harper](https://github.com/peterharperuk) Source: https://github.com/raspberrypi/pico-examples/pull/392 Signed-off-by: Samveen --- shared/netutils/dhcpserver.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/shared/netutils/dhcpserver.c b/shared/netutils/dhcpserver.c index 50cd69a1eb..dca95507d3 100644 --- a/shared/netutils/dhcpserver.c +++ b/shared/netutils/dhcpserver.c @@ -118,7 +118,7 @@ static int dhcp_socket_bind(struct udp_pcb **udp, uint32_t ip, uint16_t port) { return udp_bind(*udp, &addr, port); } -static int dhcp_socket_sendto(struct udp_pcb **udp, const void *buf, size_t len, uint32_t ip, uint16_t port) { +static int dhcp_socket_sendto(struct udp_pcb **udp, struct netif *netif, const void *buf, size_t len, uint32_t ip, uint16_t port) { if (len > 0xffff) { len = 0xffff; } @@ -132,7 +132,12 @@ static int dhcp_socket_sendto(struct udp_pcb **udp, const void *buf, size_t len, ip_addr_t dest; IP4_ADDR(&dest, ip >> 24 & 0xff, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff); - err_t err = udp_sendto(*udp, p, &dest, port); + err_t err; + if (netif != NULL) { + err = udp_sendto_if(*udp, p, &dest, port, netif); + } else { + err = udp_sendto(*udp, p, &dest, port); + } pbuf_free(p); @@ -153,7 +158,7 @@ static uint8_t *opt_find(uint8_t *opt, uint8_t cmd) { return NULL; } -static void opt_write_n(uint8_t **opt, uint8_t cmd, size_t n, void *data) { +static void opt_write_n(uint8_t **opt, uint8_t cmd, size_t n, const void *data) { uint8_t *o = *opt; *o++ = cmd; *o++ = n; @@ -281,7 +286,8 @@ static void dhcp_server_process(void *arg, struct udp_pcb *upcb, struct pbuf *p, 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; - dhcp_socket_sendto(&d->udp, &dhcp_msg, opt - (uint8_t *)&dhcp_msg, 0xffffffff, PORT_DHCP_CLIENT); + struct netif *netif = ip_current_input_netif(); + dhcp_socket_sendto(&d->udp, netif, &dhcp_msg, opt - (uint8_t *)&dhcp_msg, 0xffffffff, PORT_DHCP_CLIENT); ignore_request: pbuf_free(p);