udhcpc: in fill_envp, export BOOTP fields first

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 36 insertions, 18 deletions

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index d67769e..36c8a3d 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -393,7 +393,7 @@ static char **fill_envp(struct dhcp_packet *packet)
 				if (i == DHCP_OPTION_OVERLOAD)
 					overload = *temp;
 				else if (i == DHCP_SUBNET)
-					envc++; /* for mton */
+					envc++; /* for $mask */
 				envc++;
 				/*if (i != DHCP_MESSAGE_TYPE)*/
 				FOUND_OPTS(i) |= BMASK(i);
@@ -408,10 +408,42 @@ static char **fill_envp(struct dhcp_packet *packet)
 	if (!packet)
 		return envp;
 
+	/* Export BOOTP fields. Fields we don't (yet?) export:
+	 * uint8_t op;      // always BOOTREPLY
+	 * uint8_t htype;   // hardware address type. 1 = 10mb ethernet
+	 * uint8_t hlen;    // hardware address length
+	 * uint8_t hops;    // used by relay agents only
+	 * uint32_t xid;
+	 * uint16_t secs;   // elapsed since client began acquisition/renewal
+	 * uint16_t flags;  // only one flag so far: bcast. Never set by server
+	 * uint32_t ciaddr; // client IP (usually == yiaddr. can it be different
+	 *                  // if during renew server wants to give us differn IP?)
+	 * uint32_t gateway_nip; // relay agent IP address
+	 * uint8_t chaddr[16]; // link-layer client hardware address (MAC)
+	 * TODO: export gateway_nip as $giaddr?
+	 */
+	/* Most important one: yiaddr as $ip */
 	*curr = xmalloc(sizeof("ip=255.255.255.255"));
 	sprint_nip(*curr, "ip=", (uint8_t *) &packet->yiaddr);
 	putenv(*curr++);
+	if (packet->siaddr_nip) {
+		/* IP address of next server to use in bootstrap */
+		*curr = xmalloc(sizeof("siaddr=255.255.255.255"));
+		sprint_nip(*curr, "siaddr=", (uint8_t *) &packet->siaddr_nip);
+		putenv(*curr++);
+	}
+	if (!(overload & FILE_FIELD) && packet->file[0]) {
+		/* watch out for invalid packets */
+		*curr = xasprintf("boot_file=%."DHCP_PKT_FILE_LEN_STR"s", packet->file);
+		putenv(*curr++);
+	}
+	if (!(overload & SNAME_FIELD) && packet->sname[0]) {
+		/* watch out for invalid packets */
+		*curr = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname);
+		putenv(*curr++);
+	}
 
+	/* Export known DHCP options */
 	opt_name = dhcp_option_strings;
 	i = 0;
 	while (*opt_name) {
@@ -428,29 +460,14 @@ static char **fill_envp(struct dhcp_packet *packet)
 			/* Subnet option: make things like "$ip/$mask" possible */
 			uint32_t subnet;
 			move_from_unaligned32(subnet, temp);
-			*curr = xasprintf("mask=%d", mton(subnet));
+			*curr = xasprintf("mask=%u", mton(subnet));
 			putenv(*curr++);
 		}
  next:
 		opt_name += strlen(opt_name) + 1;
 		i++;
 	}
-	if (packet->siaddr_nip) {
-		*curr = xmalloc(sizeof("siaddr=255.255.255.255"));
-		sprint_nip(*curr, "siaddr=", (uint8_t *) &packet->siaddr_nip);
-		putenv(*curr++);
-	}
-	if (!(overload & FILE_FIELD) && packet->file[0]) {
-		/* watch out for invalid packets */
-		*curr = xasprintf("boot_file=%."DHCP_PKT_FILE_LEN_STR"s", packet->file);
-		putenv(*curr++);
-	}
-	if (!(overload & SNAME_FIELD) && packet->sname[0]) {
-		/* watch out for invalid packets */
-		*curr = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname);
-		putenv(*curr++);
-	}
-	/* Handle unknown options */
+	/* Export unknown options */
 	for (i = 0; i < 256;) {
 		BITMAP bitmap = FOUND_OPTS(i);
 		if (!bitmap) {
@@ -472,6 +489,7 @@ static char **fill_envp(struct dhcp_packet *packet)
 		}
 		i++;
 	}
+
 	return envp;
 }