wip dhcplukeshu/dhcp

3 files changed, 80 insertions, 87 deletions

diff --git a/libdhcp/CMakeLists.txt b/libdhcp/CMakeLists.txt
index a14fd50..3830217 100644
--- a/libdhcp/CMakeLists.txt
+++ b/libdhcp/CMakeLists.txt
@@ -6,7 +6,7 @@
 add_library(libdhcp INTERFACE)
 target_include_directories(libdhcp SYSTEM INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}/include)
 target_sources(libdhcp INTERFACE
-	dhcp.c
+	client.c
 )
 target_link_libraries(libdhcp INTERFACE
 	libmisc
diff --git a/libdhcp/dhcp.c b/libdhcp/client.c
index 9786018..b8f1001 100644
--- a/libdhcp/dhcp.c
+++ b/libdhcp/client.c
@@ -1,4 +1,4 @@
-/* libdhcp/dhcp.c - A DHCP client
+/* libdhcp/client.c - A DHCP client
  *
  * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-License-Identifier: AGPL-3.0-or-later
@@ -68,7 +68,8 @@
 
 #include <libmisc/endian.h>
 #include <libmisc/vcall.h>
-#include <libdhcp/dhcp.h>
+
+#include <libdhcp/client.h>
 
 /* Config *********************************************************************/
 
@@ -83,6 +84,9 @@
 #ifndef CONFIG_DHCP_SECS
 	#define CONFIG_DHCP_SECS                0
 #endif
+#ifndef CONFIG_DHCP_SELECTING_NS
+	#define CONFIG_DHCP_SELECTING_NS        (5*NS_PER_S)
+#endif
 #ifndef CONFIG_DHCP_OPT_SIZE
 	#define CONFIG_DHCP_OPT_SIZE            312
 #endif
@@ -449,28 +453,38 @@ static void dhcp_send_DECLINE(implements_net_packet_conn *sock) {
 	VCALL(sock, sendto, pDHCPMSG, DHCP_MSG_BASE_SIZE + k, net_ip4_addr_broadcast, DHCP_PORT_SERVER);
 }
 
-static int8_t dhcp_msg_parse(implements_net_packet_conn *sock) {
+/**
+ * @return
+ *   - <0: -errno
+ *   -  0: ???
+ *   - >0 && <= UINT8_MAX: msgtyp
+ *   - >UINT8_MAX: ???
+ */
+static int dhcp_recv_msg(implements_net_packet_conn *sock) {
 	struct net_ip4_addr srv_addr;
 	uint16_t            srv_port;
-	size_t               msg_len;
+	ssize_t             msg_len;
+ restart:
 	msg_len = VCALL(sock, recvfrom, pDHCPMSG, sizeof(*pDHCPMSG), &srv_addr, &srv_port);
+	if (msg_len < 0)
+		return msg_len;
 	debugf("DHCP message : %d.%d.%d.%d(%d) %d received.",
 	       srv_addr.octets[0], srv_addr.octets[1], srv_addr.octets[2], srv_addr.octets[3], srv_port, msg_len);
 	/* Compare server port.  */
 	if (srv_port != DHCP_PORT_SERVER) {
-		return 0;
+		goto restart;
 	}
 	/* Compare our MAC address.  */
 	if (memcmp(pDHCPMSG->chaddr, self_eth_addr.octets, sizeof(self_eth_addr))) {
 		debugf("Not my DHCP Message.  This message is ignored.");
-		return 0;
+		goto restart;
 	}
 	/* Compare server IP address.  */
 	if (memcmp(DHCP_SIP.octets, ((struct net_ip4_addr){0}).octets, sizeof(struct net_ip4_addr))) {
 		if ( memcmp(srv_addr.octets, DHCP_SIP.octets, sizeof(srv_addr)) &&
 		     memcmp(srv_addr.octets, DHCP_REAL_SIP.octets, sizeof(srv_addr)) ) {
 			debugf("Another DHCP sever send a response message. This is ignored.");
-			return 0;
+			goto restart;
 		}
 	}
 
@@ -595,10 +609,10 @@ static int8_t dhcp_check_leasedIP(implements_net_packet_conn *sock) {
 	return 0;
 }
 
-COROUTINE DHCP_cr(struct w5500 *chip, uint8_t socknum,
-                  struct net_eth_addr self_eth_addr,
-                  char *self_hostname,
-                  dhcp_callback_t cb) {
+COROUTINE dhcp_client_cr(struct w5500 *chip, uint8_t socknum,
+                         struct net_eth_addr self_eth_addr,
+                         char *self_hostname,
+                         dhcp_callback_t cb) {
 	uint32_t xid;
 	implements_net_packet_conn *sock;
 
@@ -613,58 +627,65 @@ COROUTINE DHCP_cr(struct w5500 *chip, uint8_t socknum,
 	dhcp_tick_1s = 0;
 	dhcp_tick_next = DHCP_WAIT_TIME;
 	dhcp_retry_count = 0;
-	dhcp_state = STATE_DHCP_INIT;
 
 	sock = w5500_udp_conn(chip, socknum, DHCP_PORT_CLIENT);
 
-		ret = DHCP_RET_RUNNING;
-		msg_type = dhcp_msg_parse(sock);
+	int r;
+
+	dhcp_state = STATE_DHCP_INIT;
+	uint64_t time_ns_init;
 
 	for (;;) {
 		/* State transition diagram: https://datatracker.ietf.org/doc/html/rfc2131#page-35 */
 		switch (state) {
-	case STATE_DHCP_INIT:
-		dhcp_send_DISCOVER(sock);
-		dhcp_state = STATE_DHCP_DISCOVER;
-		break;
-	case STATE_DHCP_DISCOVER :
-		if (msg_type == DHCP_MSGTYP_OFFER){
-			debugf("> Receive DHCP_OFFER");
-			global_lease.addr = pDHCPMSG->yiaddr;
-
-			dhcp_send_REQUEST(sock);
-			dhcp_state = STATE_DHCP_REQUEST;
-		} else
-			ret = dhcp_check_timeout(sock);
-		break;
+		case STATE_DHCP_INIT:
+			dhcp_send_DISCOVER(sock);
+			time_ns_init = VCALL(bootclock, get_time_ns);
+			VCALL(sock, set_read_deadline(time_ns_init+CONFIG_DHCP_SELECTING_NS));
+			dhcp_state = STATE_DHCP_SELECTING;
+			break;
+		case STATE_DHCP_SELECTING :
+			switch ((r = dhcp_recv_msg(sock))) {
+			case DHCP_MSGTYP_OFFER:
+				debugf("> Receive DHCP_OFFER");
+				global_lease.addr = pDHCPMSG->yiaddr;
+				dhcp_send_REQUEST(sock);
+				dhcp_state = STATE_DHCP_REQUEST;
+				break;
+			case -NET_ETIMEDOUT:
+				break;
+			default:
+				debugf("unexpected error: %d", r);
+			}
+			break;
 
-	case STATE_DHCP_REQUEST :
-		if (msg_type == DHCP_MSGTYP_ACK) {
-			debugf("> Receive DHCP_ACK");
-			if (dhcp_check_leasedIP(sock)) {
-				/* Network info assignment from DHCP */
-				cb(DHCP_ASSIGN, global_lease);
-				dhcp_reset_timeout();
+		case STATE_DHCP_REQUEST :
+			if (msg_type == DHCP_MSGTYP_ACK) {
+				debugf("> Receive DHCP_ACK");
+				if (dhcp_check_leasedIP(sock)) {
+					/* Network info assignment from DHCP */
+					cb(DHCP_ASSIGN, global_lease);
+					dhcp_reset_timeout();
+
+					dhcp_state = STATE_DHCP_LEASED;
+				} else {
+					/* IP address conflict occurred */
+					dhcp_reset_timeout();
+					cb(DHCP_CONFLICT, global_lease);
+					dhcp_state = STATE_DHCP_INIT;
+				}
+			} else if (msg_type == DHCP_MSGTYP_NAK) {
+				debugf("> Receive DHCP_NACK");
 
-				dhcp_state = STATE_DHCP_LEASED;
-			} else {
-				/* IP address conflict occurred */
 				dhcp_reset_timeout();
-				cb(DHCP_CONFLICT, global_lease);
-				dhcp_state = STATE_DHCP_INIT;
-			}
-		} else if (msg_type == DHCP_MSGTYP_NAK) {
-			debugf("> Receive DHCP_NACK");
 
-			dhcp_reset_timeout();
-
-			dhcp_state = STATE_DHCP_DISCOVER;
-		} else
-			ret = dhcp_check_timeout(sock);
-		break;
+				dhcp_state = STATE_DHCP_DISCOVER;
+			} else
+				ret = dhcp_check_timeout(sock);
+			break;
 
-	case STATE_DHCP_LEASED :
-		ret = DHCP_RET_IP_LEASED;
+		case STATE_DHCP_LEASED :
+			ret = DHCP_RET_IP_LEASED;
 		if ((global_lease.lifetime != DHCP_INFINITY) && ((global_lease.lifetime/2) < dhcp_tick_1s)) {
 			debugf("> Maintains the IP address");
 
diff --git a/libdhcp/include/libdhcp/dhcp.h b/libdhcp/include/libdhcp/client.h
index 0b4c06f..fcff759 100644
--- a/libdhcp/include/libdhcp/dhcp.h
+++ b/libdhcp/include/libdhcp/client.h
@@ -1,4 +1,4 @@
-/* libdhcp/dhcp.h - A DHCP client
+/* libdhcp/client.h - A DHCP client
  *
  * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-License-Identifier: AGPL-3.0-or-later
@@ -68,7 +68,7 @@
 #define _LIBDHCP_DHCP_H_
 
 #include <libhw/generic/net.h>
-#include "hw/w5500.h"
+#include <libhw/w5500.h>
 
 enum dhcp_event {
 	DHCP_ASSIGN,
@@ -94,40 +94,12 @@ enum {
 	DHCP_RET_STOPPED      // Stop processing DHCP protocol
 };
 
-/*
- * @brief DHCP client initialization (outside of the main loop)
- * @param buf - buffer for processing DHCP message
- */
-void DHCP_init(void *buf);
-
-/*
- * @brief DHCP 1s Tick Timer handler
- * @note SHOULD BE register to your system 1s Tick timer handler
- */
-void DHCP_time_handler(void);
-
-/*
- * @brief DHCP client in the main loop
- * @return    The value is as the follow \n
- *            @ref DHCP_FAILED     \n
- *            @ref DHCP_RUNNING    \n
- *            @ref DHCP_IP_ASSIGN  \n
- *            @ref DHCP_IP_CHANGED \n
- * 			  @ref DHCP_IP_LEASED  \n
- *            @ref DHCP_STOPPED    \n
- *
- * @note This function is always called by you main task.
- */
-uint8_t DHCP_run(struct w5500 *chip, uint8_t socknum, dhcp_callback_t cb);
-//uint8_t DHCP_run(implements_net_packet_conn *sock, dhcp_callback_t cb);
-
-/*
- * @brief Stop DHCP processing
- * @note If you want to restart. call DHCP_init() and DHCP_run()
- */
-void    DHCP_stop(implements_net_packet_conn *sock);
+COROUTINE dhcp_client_cr(struct w5500 *chip, uint8_t socknum,
+                  struct net_eth_addr self_eth_addr,
+                  char *self_hostname,
+                  dhcp_callback_t cb);
 
-void xhandle(uint8_t opt_typ, uint8_t opt_len, uint8_t *opt_dat) {
+static void xhandle(uint8_t opt_typ, uint8_t opt_len, uint8_t *opt_dat) {
 	switch (opt_typ) {
 	case DHCP_OPT_SUBNET_MASK:
 		if (opt_len != 4)