gdhcp: Use host byte order internally

Convert to network byte order just before sending the packet.

5 files changed, 58 insertions, 71 deletions

diff --git a/gdhcp/client.c b/gdhcp/client.c
index cf04ced7..7340f3a0 100644
--- a/gdhcp/client.c
+++ b/gdhcp/client.c
@@ -367,7 +367,7 @@ static int send_discover(GDHCPClient *dhcp_client, uint32_t requested)
 
 	/* Explicitly saying that we want RFC-compliant packets helps
 	 * some buggy DHCP servers to NOT send bigger packets */
-	dhcp_add_simple_option(&packet, DHCP_MAX_SIZE, htons(576));
+	dhcp_add_simple_option(&packet, DHCP_MAX_SIZE, 576);
 
 	add_request_options(dhcp_client, &packet);
 
@@ -410,7 +410,7 @@ static int send_renew(GDHCPClient *dhcp_client)
 
 	init_packet(dhcp_client , &packet, DHCPREQUEST);
 	packet.xid = dhcp_client->xid;
-	packet.ciaddr = dhcp_client->requested_ip;
+	packet.ciaddr = htonl(dhcp_client->requested_ip);
 
 	add_request_options(dhcp_client, &packet);
 
@@ -429,7 +429,7 @@ static int send_rebound(GDHCPClient *dhcp_client)
 
 	init_packet(dhcp_client , &packet, DHCPREQUEST);
 	packet.xid = dhcp_client->xid;
-	packet.ciaddr = dhcp_client->requested_ip;
+	packet.ciaddr = htonl(dhcp_client->requested_ip);
 
 	add_request_options(dhcp_client, &packet);
 
@@ -449,7 +449,7 @@ static int send_release(GDHCPClient *dhcp_client,
 
 	init_packet(dhcp_client, &packet, DHCPRELEASE);
 	packet.xid = rand();
-	packet.ciaddr = ciaddr;
+	packet.ciaddr = htonl(ciaddr);
 
 	dhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
 
@@ -1134,7 +1134,7 @@ static int ipv4ll_recv_arp_packet(GDHCPClient *dhcp_client)
 			arp.arp_op != htons(ARPOP_REQUEST))
 		return -EINVAL;
 
-	ip_requested = ntohl(dhcp_client->requested_ip);
+	ip_requested = htonl(dhcp_client->requested_ip);
 	source_conflict = !memcmp(arp.arp_spa, &ip_requested,
 						sizeof(ip_requested));
 
@@ -1333,15 +1333,14 @@ static void start_request(GDHCPClient *dhcp_client)
 
 static uint32_t get_lease(struct dhcp_packet *packet)
 {
-	uint8_t *option_u8;
+	uint8_t *option;
 	uint32_t lease_seconds;
 
-	option_u8 = dhcp_get_option(packet, DHCP_LEASE_TIME);
-	if (option_u8 == NULL)
+	option = dhcp_get_option(packet, DHCP_LEASE_TIME);
+	if (option == NULL)
 		return 3600;
 
-	lease_seconds = dhcp_get_unaligned((uint32_t *) option_u8);
-	lease_seconds = ntohl(lease_seconds);
+	lease_seconds = get_be32(option);
 	/* paranoia: must not be prone to overflows */
 	lease_seconds &= 0x0fffffff;
 	if (lease_seconds < 10)
@@ -1518,16 +1517,13 @@ static char *malloc_option_value_string(uint8_t *option, GDHCPOptionType type)
 			dest += sprint_nip(dest, "", option);
 			break;
 		case OPTION_U16: {
-			uint16_t val_u16 = dhcp_get_unaligned(
-						(uint16_t *) option);
-			dest += sprintf(dest, "%u", ntohs(val_u16));
+			uint16_t val_u16 = get_be16(option);
+			dest += sprintf(dest, "%u", val_u16);
 			break;
 		}
 		case OPTION_U32: {
-			uint32_t val_u32 = dhcp_get_unaligned(
-						(uint32_t *) option);
-			dest += sprintf(dest, type == OPTION_U32 ? "%lu" :
-					"%ld", (unsigned long) ntohl(val_u32));
+			uint32_t val_u32 = get_be32(option);
+			dest += sprintf(dest, "%u", val_u32);
 			break;
 		}
 		case OPTION_STRING:
@@ -1821,7 +1817,7 @@ static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
 	GDHCPClient *dhcp_client = user_data;
 	struct dhcp_packet packet;
 	struct dhcpv6_packet *packet6 = NULL;
-	uint8_t *message_type = NULL, *client_id = NULL, *option_u8,
+	uint8_t *message_type = NULL, *client_id = NULL, *option,
 		*server_id = NULL;
 	uint16_t option_len = 0, status = 0;
 	gpointer pkt;
@@ -1882,15 +1878,15 @@ static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
 			return TRUE;
 		}
 
-		option_u8 = dhcpv6_get_option(packet6, pkt_len,
+		option = dhcpv6_get_option(packet6, pkt_len,
 				G_DHCPV6_STATUS_CODE, &option_len, NULL);
-		if (option_u8 != 0 && option_len > 0) {
-			status = option_u8[0]<<8 | option_u8[1];
+		if (option != 0 && option_len > 0) {
+			status = option[0]<<8 | option[1];
 			if (status != 0) {
 				debug(dhcp_client, "error code %d", status);
 				if (option_len > 2) {
 					gchar *txt = g_strndup(
-						(gchar *)&option_u8[2],
+						(gchar *)&option[2],
 						option_len - 2);
 					debug(dhcp_client, "error text: %s",
 						txt);
@@ -1923,10 +1919,9 @@ static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
 		dhcp_client->timeout = 0;
 		dhcp_client->retry_times = 0;
 
-		option_u8 = dhcp_get_option(&packet, DHCP_SERVER_ID);
-		dhcp_client->server_ip =
-				dhcp_get_unaligned((uint32_t *) option_u8);
-		dhcp_client->requested_ip = packet.yiaddr;
+		option = dhcp_get_option(&packet, DHCP_SERVER_ID);
+		dhcp_client->server_ip = get_be32(option);
+		dhcp_client->requested_ip = ntohl(packet.yiaddr);
 
 		dhcp_client->state = REQUESTING;
 
diff --git a/gdhcp/common.c b/gdhcp/common.c
index 8d5c284b..55fddcbf 100644
--- a/gdhcp/common.c
+++ b/gdhcp/common.c
@@ -280,11 +280,21 @@ void dhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code,
 	len = dhcp_option_lengths[type & OPTION_TYPE_MASK];
 	option[OPT_LEN] = len;
 
-#if __BYTE_ORDER == __BIG_ENDIAN
-	data <<= 8 * (4 - len);
-#endif
+	switch (len) {
+	case 1:
+		option[OPT_DATA] = data;
+		break;
+	case 2:
+		put_be16(data, option + OPT_DATA);
+		break;
+	case 4:
+		put_be32(data, option + OPT_DATA);
+		break;
+	default:
+		printf("Invalid option len %d for code 0x%x\n", len, code);
+		return;
+	}
 
-	dhcp_put_unaligned(data, (uint32_t *)(option + OPT_DATA));
 	dhcp_add_binary_option(packet, option);
 
 	return;
@@ -575,7 +585,7 @@ int dhcp_send_kernel_packet(struct dhcp_packet *dhcp_pkt,
 	memset(&client, 0, sizeof(client));
 	client.sin_family = AF_INET;
 	client.sin_port = htons(source_port);
-	client.sin_addr.s_addr = source_ip;
+	client.sin_addr.s_addr = htonl(source_ip);
 	if (bind(fd, (struct sockaddr *) &client, sizeof(client)) < 0) {
 		close(fd);
 		return -errno;
diff --git a/gdhcp/common.h b/gdhcp/common.h
index 13f49d8e..e2bfc6c8 100644
--- a/gdhcp/common.h
+++ b/gdhcp/common.h
@@ -24,24 +24,9 @@
 
 #include <glib.h>
 
+#include "unaligned.h"
 #include "gdhcp.h"
 
-#define dhcp_get_unaligned(ptr)			\
-({						\
-	struct __attribute__((packed)) {	\
-		typeof(*(ptr)) __v;		\
-	} *__p = (void *) (ptr);		\
-	__p->__v;				\
-})
-
-#define dhcp_put_unaligned(val, ptr)		\
-do {						\
-	struct __attribute__((packed)) {	\
-		typeof(*(ptr)) __v;		\
-	} *__p = (void *) (ptr);		\
-	__p->__v = (val);			\
-} while (0)
-
 #define CLIENT_PORT 68
 #define SERVER_PORT 67
 
diff --git a/gdhcp/ipv4ll.c b/gdhcp/ipv4ll.c
index 4c095722..007ffe6b 100644
--- a/gdhcp/ipv4ll.c
+++ b/gdhcp/ipv4ll.c
@@ -36,7 +36,7 @@
 #include "ipv4ll.h"
 
 /**
- * Return a random link local IP
+ * Return a random link local IP (in host byte order)
  */
 uint32_t ipv4ll_random_ip(int seed)
 {
@@ -53,7 +53,7 @@ uint32_t ipv4ll_random_ip(int seed)
 		tmp = rand();
 		tmp = tmp & IN_CLASSB_HOST;
 	} while (tmp > (IN_CLASSB_HOST - 0x0200));
-	return ((LINKLOCAL_ADDR + 0x0100) + tmp);
+	return ntohl(((LINKLOCAL_ADDR + 0x0100) + tmp));
 }
 
 /**
diff --git a/gdhcp/server.c b/gdhcp/server.c
index 9ac09b54..2de7db69 100644
--- a/gdhcp/server.c
+++ b/gdhcp/server.c
@@ -140,7 +140,7 @@ static int get_lease(GDHCPServer *dhcp_server, uint32_t yiaddr,
 	lease_mac = find_lease_by_mac(dhcp_server, mac);
 
 	lease_nip = g_hash_table_lookup(dhcp_server->nip_lease_hash,
-						GINT_TO_POINTER((int) yiaddr));
+					GINT_TO_POINTER((int) ntohl(yiaddr)));
 	debug(dhcp_server, "lease_mac %p lease_nip %p", lease_mac, lease_nip);
 
 	if (lease_nip != NULL) {
@@ -148,7 +148,7 @@ static int get_lease(GDHCPServer *dhcp_server, uint32_t yiaddr,
 				g_list_remove(dhcp_server->lease_list,
 								lease_nip);
 		g_hash_table_remove(dhcp_server->nip_lease_hash,
-					GINT_TO_POINTER((int) yiaddr));
+				GINT_TO_POINTER((int) ntohl(yiaddr)));
 
 		if (lease_mac == NULL)
 			*lease = lease_nip;
@@ -200,7 +200,7 @@ static struct dhcp_lease *add_lease(GDHCPServer *dhcp_server, uint32_t expire,
 	memset(lease, 0, sizeof(*lease));
 
 	memcpy(lease->lease_mac, chaddr, ETH_ALEN);
-	lease->lease_nip = yiaddr;
+	lease->lease_nip = ntohl(yiaddr);
 
 	if (expire == 0)
 		lease->expire = time(NULL) + dhcp_server->lease_seconds;
@@ -254,13 +254,12 @@ static uint32_t find_free_or_expired_nip(GDHCPServer *dhcp_server,
 		if ((ip_addr & 0xff) == 0xff)
 			continue;
 
-		lease = find_lease_by_nip(dhcp_server,
-				(uint32_t) htonl(ip_addr));
+		lease = find_lease_by_nip(dhcp_server, ip_addr);
 		if (lease != NULL)
 			continue;
 
 		if (arp_check(htonl(ip_addr), safe_mac) == TRUE)
-			return htonl(ip_addr);
+			return ip_addr;
 	}
 
 	/* The last lease is the oldest one */
@@ -471,7 +470,7 @@ static void add_option(gpointer key, gpointer value, gpointer user_data)
 			return;
 
 		dhcp_add_simple_option(packet, (uint8_t) option_code,
-								nip.s_addr);
+							ntohl(nip.s_addr));
 		break;
 	default:
 		return;
@@ -493,10 +492,10 @@ static gboolean check_requested_nip(GDHCPServer *dhcp_server,
 	if (requested_nip == 0)
 		return FALSE;
 
-	if (ntohl(requested_nip) < dhcp_server->start_ip)
+	if (requested_nip < dhcp_server->start_ip)
 		return FALSE;
 
-	if (ntohl(requested_nip) > dhcp_server->end_ip)
+	if (requested_nip > dhcp_server->end_ip)
 		return FALSE;
 
 	lease = find_lease_by_nip(dhcp_server, requested_nip);
@@ -543,12 +542,12 @@ static void send_offer(GDHCPServer *dhcp_server,
 	init_packet(dhcp_server, &packet, client_packet, DHCPOFFER);
 
 	if (lease)
-		packet.yiaddr = lease->lease_nip;
+		packet.yiaddr = htonl(lease->lease_nip);
 	else if (check_requested_nip(dhcp_server, requested_nip) == TRUE)
-		packet.yiaddr = requested_nip;
+		packet.yiaddr = htonl(requested_nip);
 	else
-		packet.yiaddr = find_free_or_expired_nip(
-				dhcp_server, client_packet->chaddr);
+		packet.yiaddr = htonl(find_free_or_expired_nip(
+					dhcp_server, client_packet->chaddr));
 
 	debug(dhcp_server, "find yiaddr %u", packet.yiaddr);
 
@@ -566,7 +565,7 @@ static void send_offer(GDHCPServer *dhcp_server,
 	}
 
 	dhcp_add_simple_option(&packet, DHCP_LEASE_TIME,
-				htonl(dhcp_server->lease_seconds));
+						dhcp_server->lease_seconds);
 	add_server_options(dhcp_server, &packet);
 
 	addr.s_addr = packet.yiaddr;
@@ -590,22 +589,22 @@ static void save_lease(GDHCPServer *dhcp_server)
 }
 
 static void send_ACK(GDHCPServer *dhcp_server,
-		struct dhcp_packet *client_packet, uint32_t yiaddr)
+		struct dhcp_packet *client_packet, uint32_t dest)
 {
 	struct dhcp_packet packet;
 	uint32_t lease_time_sec;
 	struct in_addr addr;
 
 	init_packet(dhcp_server, &packet, client_packet, DHCPACK);
-	packet.yiaddr = yiaddr;
+	packet.yiaddr = htonl(dest);
 
 	lease_time_sec = dhcp_server->lease_seconds;
 
-	dhcp_add_simple_option(&packet, DHCP_LEASE_TIME, htonl(lease_time_sec));
+	dhcp_add_simple_option(&packet, DHCP_LEASE_TIME, lease_time_sec);
 
 	add_server_options(dhcp_server, &packet);
 
-	addr.s_addr = yiaddr;
+	addr.s_addr = htonl(dest);
 
 	debug(dhcp_server, "Sending ACK to %s", inet_ntoa(addr));
 
@@ -664,8 +663,7 @@ static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
 
 	server_id_option = dhcp_get_option(&packet, DHCP_SERVER_ID);
 	if (server_id_option) {
-		uint32_t server_nid = dhcp_get_unaligned(
-					(uint32_t *) server_id_option);
+		uint32_t server_nid = get_be32(server_id_option);
 
 		if (server_nid != dhcp_server->server_nip)
 			return TRUE;
@@ -673,8 +671,7 @@ static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
 
 	request_ip_option = dhcp_get_option(&packet, DHCP_REQUESTED_IP);
 	if (request_ip_option)
-		requested_nip = dhcp_get_unaligned(
-					(uint32_t *) request_ip_option);
+		requested_nip = get_be32(request_ip_option);
 
 	lease = find_lease_by_mac(dhcp_server, packet.chaddr);