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 d67769e65..36c8a3dd3 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;
 }