[dhcp] Clarify language surrounding ProxyDHCP

Remove the lazy assumption that ProxyDHCP == "DHCP with option 60 set
to PXEClient", and explicitly separate the notion of ProxyDHCP from
the notion of packets containing PXE options.

diff --git a/src/include/gpxe/dhcp.h b/src/include/gpxe/dhcp.h
index c45004c..66aa50a 100644 (file)
--- a/src/include/gpxe/dhcp.h
+++ b/src/include/gpxe/dhcp.h
@@ -25,8 +25,8 @@ struct dhcp_pxe_boot_menu_item;
 /** BOOTP/DHCP client port */
 #define BOOTPC_PORT 68
 
-/** ProxyDHCP server port */
-#define PROXYDHCP_PORT 4011
+/** PXE server port */
+#define PXE_PORT 4011
 
 /** Construct a tag value for an encapsulated option
  *
@@ -207,12 +207,12 @@ struct dhcp_pxe_boot_menu_item;
  *
  */
 
-/** Ignore ProxyDHCP
+/** Skip PXE DHCP protocol extensions such as ProxyDHCP
  *
  * If set to a non-zero value, gPXE will not wait for ProxyDHCP offers
- * and will ignore any ProxyDHCP offers that it receives.
+ * and will ignore any PXE-specific DHCP offers that it receives.
  */
-#define DHCP_EB_NO_PROXYDHCP DHCP_ENCAP_OPT ( DHCP_EB_ENCAP, 0xb0 )
+#define DHCP_EB_NO_PXEDHCP DHCP_ENCAP_OPT ( DHCP_EB_ENCAP, 0xb0 )
 
 /** Network device descriptor
  *

diff --git a/src/net/udp/dhcp.c b/src/net/udp/dhcp.c
index 14de828..7140367 100644 (file)
--- a/src/net/udp/dhcp.c
+++ b/src/net/udp/dhcp.c
@@ -340,14 +340,16 @@ struct dhcp_session {
         * (e.g. @c DHCPDISCOVER).
         */
        enum dhcp_session_state state;
-       /** DHCPOFFER obtained during DHCPDISCOVER */
+       /** DHCPOFFER obtained during DHCPDISCOVER containing IP address */
        struct dhcp_settings *dhcpoffer;
-       /** ProxyDHCPOFFER obtained during DHCPDISCOVER */
-       struct dhcp_settings *proxydhcpoffer;
-       /** DHCPACK obtained during DHCPREQUEST */
+       /** DHCPOFFER obtained during DHCPDISCOVER containing "PXEClient" */
+       struct dhcp_settings *pxedhcpoffer;
+       /** DHCPACK obtained during DHCPREQUEST containing IP address */
        struct dhcp_settings *dhcpack;
-       /** ProxyDHCPACK obtained during ProxyDHCPREQUEST */
-       struct dhcp_settings *proxydhcpack;
+       /** DHCPACK obtained during DHCPREQUEST or ProxyDHCPREQUEST
+        * containing "PXEClient"
+        */
+       struct dhcp_settings *pxedhcpack;
        /** BootServerDHCPACK obtained during BootServerDHCPREQUEST */
        struct dhcp_settings *bsdhcpack;
        /** Retransmission timer */
@@ -367,9 +369,9 @@ static void dhcp_free ( struct refcnt *refcnt ) {
 
        netdev_put ( dhcp->netdev );
        dhcpset_put ( dhcp->dhcpoffer );
-       dhcpset_put ( dhcp->proxydhcpoffer );
+       dhcpset_put ( dhcp->pxedhcpoffer );
        dhcpset_put ( dhcp->dhcpack );
-       dhcpset_put ( dhcp->proxydhcpack );
+       dhcpset_put ( dhcp->pxedhcpack );
        dhcpset_put ( dhcp->bsdhcpack );
        free ( dhcp );
 }
@@ -586,7 +588,7 @@ int dhcp_create_request ( struct dhcp_packet *dhcppkt,
 static int dhcp_tx ( struct dhcp_session *dhcp ) {
        static struct sockaddr_in dest = {
                .sin_family = AF_INET,
-               .sin_port = htons ( PROXYDHCP_PORT ),
+               .sin_port = htons ( PXE_PORT ),
        };
        static struct sockaddr_in src = {
                .sin_family = AF_INET,
@@ -624,11 +626,11 @@ static int dhcp_tx ( struct dhcp_session *dhcp ) {
                break;
        case DHCP_STATE_PROXYREQUEST:
                assert ( dhcp->dhcpoffer );
-               assert ( dhcp->proxydhcpoffer );
+               assert ( dhcp->pxedhcpoffer );
                assert ( dhcp->dhcpack );
                msgtype = DHCPREQUEST;
                ciaddr = dhcp->dhcpoffer->dhcppkt.dhcphdr->yiaddr;
-               dhcppkt_fetch ( &dhcp->proxydhcpoffer->dhcppkt,
+               dhcppkt_fetch ( &dhcp->pxedhcpoffer->dhcppkt,
                                DHCP_SERVER_IDENTIFIER, &dest.sin_addr,
                                sizeof ( dest.sin_addr ) );
                meta.dest = ( struct sockaddr * ) &dest;
@@ -638,16 +640,16 @@ static int dhcp_tx ( struct dhcp_session *dhcp ) {
                break;
        case DHCP_STATE_BSREQUEST:
                assert ( dhcp->dhcpoffer );
-               assert ( dhcp->proxydhcpoffer );
+               assert ( dhcp->pxedhcpoffer );
                assert ( dhcp->dhcpack );
-               assert ( dhcp->proxydhcpack );
+               assert ( dhcp->pxedhcpack );
                msgtype = DHCPREQUEST;
                ciaddr = dhcp->dhcpoffer->dhcppkt.dhcphdr->yiaddr;
-               dhcppkt_fetch ( &dhcp->proxydhcpack->dhcppkt,
+               dhcppkt_fetch ( &dhcp->pxedhcpack->dhcppkt,
                                DHCP_PXE_BOOT_SERVER_MCAST,
                                &dest.sin_addr, sizeof ( dest.sin_addr ) );
                meta.dest = ( struct sockaddr * ) &dest;
-               dhcppkt_fetch ( &dhcp->proxydhcpack->dhcppkt,
+               dhcppkt_fetch ( &dhcp->pxedhcpack->dhcppkt,
                                DHCP_PXE_BOOT_MENU, &menu_item.type,
                                sizeof ( menu_item.type ) );
                assert ( dest.sin_addr.s_addr );
@@ -744,21 +746,21 @@ static void dhcp_next_state ( struct dhcp_session *dhcp ) {
                dhcp_set_state ( dhcp, DHCP_STATE_REQUEST );
                break;
        case DHCP_STATE_REQUEST:
-               if ( dhcp->proxydhcpoffer ) {
-                       /* Store DHCPACK as ProxyDHCPACK.  This
-                        * handles the case in which the DHCP server
-                        * itself responds with "PXEClient" and PXE
-                        * options but there is no actual ProxyDHCP
-                        * server resident on the machine.
+               if ( dhcp->pxedhcpoffer ) {
+                       /* Store DHCPACK as PXEDHCPACK.  This handles
+                        * the case in which the DHCP server itself
+                        * responds with "PXEClient" and PXE options
+                        * but there is no ProxyDHCP server resident
+                        * on the machine.
                         */
-                       dhcp->proxydhcpack = dhcpset_get ( dhcp->dhcpack );
+                       dhcp->pxedhcpack = dhcpset_get ( dhcp->dhcpack );
                        dhcp_set_state ( dhcp, DHCP_STATE_PROXYREQUEST );
                        break;
                }
                /* Fall through */
        case DHCP_STATE_PROXYREQUEST:
-               if ( dhcp->proxydhcpack ) {
-                       dhcppkt_fetch ( &dhcp->proxydhcpack->dhcppkt,
+               if ( dhcp->pxedhcpack ) {
+                       dhcppkt_fetch ( &dhcp->pxedhcpack->dhcppkt,
                                        DHCP_PXE_BOOT_SERVER_MCAST,
                                        &bs_mcast, sizeof ( bs_mcast ) );
                        if ( bs_mcast.s_addr ) {
@@ -827,7 +829,7 @@ static void dhcp_rx_dhcpoffer ( struct dhcp_session *dhcp,
        struct in_addr server_id = { 0 };
        char vci[9]; /* "PXEClient" */
        int len;
-       uint8_t ignore_proxy = 0;
+       uint8_t ignore_pxe = 0;
        unsigned long elapsed;
 
        /* Check for presence of DHCP server ID */
@@ -849,26 +851,25 @@ static void dhcp_rx_dhcpoffer ( struct dhcp_session *dhcp,
        }
 
        /* If there is a "PXEClient" vendor class ID, it's a
-        * ProxyDHCPOFFER.  Note that it could be both a normal
-        * DHCPOFFER and a ProxyDHCPOFFER.
+        * PXEDHCPOFFER.  Note that it could be both a normal
+        * DHCPOFFER and a PXEDHCPOFFER.
         */
        len = dhcppkt_fetch ( &dhcpoffer->dhcppkt, DHCP_VENDOR_CLASS_ID,
                              vci, sizeof ( vci ) );
        if ( ( server_id.s_addr != 0 ) &&
             ( len >= ( int ) sizeof ( vci ) ) &&
             ( strncmp ( "PXEClient", vci, sizeof ( vci ) ) == 0 ) ) {
-               DBGC ( dhcp, "DHCP %p DHCPOFFER %p from %s is a "
-                      "ProxyDHCPOFFER\n",
+               DBGC ( dhcp, "DHCP %p DHCPOFFER %p from %s has PXE options\n",
                       dhcp, dhcpoffer, inet_ntoa ( server_id ) );
                dhcp_store_dhcpoffer ( dhcp, dhcpoffer,
-                                      &dhcp->proxydhcpoffer );
+                                      &dhcp->pxedhcpoffer );
        }
 
        /* We can transition to making the DHCPREQUEST when we have a
         * valid DHCPOFFER, and either:
         *
-        *  o  The DHCPOFFER instructs us to not wait for ProxyDHCP, or
-        *  o  We have a valid ProxyDHCPOFFER, or
+        *  o  The DHCPOFFER instructs us to ignore PXEDHCPOFFERs, or
+        *  o  We have a valid PXEDHCPOFFER, or
          *  o  We have allowed sufficient time for ProxyDHCPOFFERs.
         */
 
@@ -876,20 +877,20 @@ static void dhcp_rx_dhcpoffer ( struct dhcp_session *dhcp,
        if ( ! dhcp->dhcpoffer )
                return;
 
-       /* If the DHCPOFFER instructs us to ignore ProxyDHCP, discard
-        * any ProxyDHCPOFFER
+       /* If the DHCPOFFER instructs us to ignore PXEDHCP, discard
+        * any PXEDHCPOFFER
         */
-       dhcppkt_fetch ( &dhcp->dhcpoffer->dhcppkt, DHCP_EB_NO_PROXYDHCP,
-                       &ignore_proxy, sizeof ( ignore_proxy ) );
-       if ( ignore_proxy && dhcp->proxydhcpoffer ) {
-               DBGC ( dhcp, "DHCP %p discarding ProxyDHCPOFFER\n", dhcp );
-               dhcpset_put ( dhcp->proxydhcpoffer );
-               dhcp->proxydhcpoffer = NULL;
+       dhcppkt_fetch ( &dhcp->dhcpoffer->dhcppkt, DHCP_EB_NO_PXEDHCP,
+                       &ignore_pxe, sizeof ( ignore_pxe ) );
+       if ( ignore_pxe && dhcp->pxedhcpoffer ) {
+               DBGC ( dhcp, "DHCP %p discarding PXEDHCPOFFER\n", dhcp );
+               dhcpset_put ( dhcp->pxedhcpoffer );
+               dhcp->pxedhcpoffer = NULL;
        }
 
        /* If we can't yet transition to DHCPREQUEST, do nothing */
        elapsed = ( currticks() - dhcp->start );
-       if ( ! ( ignore_proxy || dhcp->proxydhcpoffer ||
+       if ( ! ( ignore_pxe || dhcp->pxedhcpoffer ||
                 ( elapsed > PROXYDHCP_WAIT_TIME ) ) )
                return;
 
@@ -978,11 +979,11 @@ static void dhcp_rx_proxydhcpack ( struct dhcp_session *dhcp,
        int rc;
 
        /* Verify server ID matches, if present */
-       assert ( dhcp->proxydhcpoffer != NULL );
+       assert ( dhcp->pxedhcpoffer != NULL );
        if ( ( rc = dhcppkt_fetch ( &proxydhcpack->dhcppkt,
                                    DHCP_SERVER_IDENTIFIER, &ack_server_id,
                                    sizeof ( ack_server_id ) ) ) > 0 ) {
-               dhcppkt_fetch ( &dhcp->proxydhcpoffer->dhcppkt,
+               dhcppkt_fetch ( &dhcp->pxedhcpoffer->dhcppkt,
                                DHCP_SERVER_IDENTIFIER, &offer_server_id,
                                sizeof ( offer_server_id ) );
                if ( offer_server_id.s_addr != ack_server_id.s_addr ) {
@@ -996,9 +997,9 @@ static void dhcp_rx_proxydhcpack ( struct dhcp_session *dhcp,
        /* Rename settings */
        proxydhcpack->settings.name = PROXYDHCP_SETTINGS_NAME;
 
-       /* Record ProxyDHCPACK */
-       dhcpset_put ( dhcp->proxydhcpack );
-       dhcp->proxydhcpack = dhcpset_get ( proxydhcpack );
+       /* Record ProxyDHCPACK as PXEDHCPACK */
+       dhcpset_put ( dhcp->pxedhcpack );
+       dhcp->pxedhcpack = dhcpset_get ( proxydhcpack );
 
        /* Register settings */
        if ( ( rc = dhcp_store_dhcpack ( dhcp, proxydhcpack, NULL ) ) != 0 )
@@ -1012,7 +1013,7 @@ static void dhcp_rx_proxydhcpack ( struct dhcp_session *dhcp,
  * Handle received BootServerDHCPACK
  *
  * @v dhcp             DHCP session
- * @v bsdhcpack        Received BootServerDHCPACK
+ * @v bsdhcpack                Received BootServerDHCPACK
  */
 static void dhcp_rx_bsdhcpack ( struct dhcp_session *dhcp,
                                struct dhcp_settings *bsdhcpack ) {
@@ -1021,7 +1022,7 @@ static void dhcp_rx_bsdhcpack ( struct dhcp_session *dhcp,
        /* Rename settings */
        bsdhcpack->settings.name = BSDHCP_SETTINGS_NAME;
 
-       /* Record ProxyDHCPACK */
+       /* Record BootServerDHCPACK */
        assert ( dhcp->bsdhcpack == NULL );
        dhcp->bsdhcpack = dhcpset_get ( bsdhcpack );
 
@@ -1107,12 +1108,12 @@ static int dhcp_deliver_iob ( struct xfer_interface *xfer,
                break;
        case DHCP_STATE_PROXYREQUEST:
                if ( ( msgtype == DHCPACK ) &&
-                    ( src_port == htons ( PROXYDHCP_PORT ) ) )
+                    ( src_port == htons ( PXE_PORT ) ) )
                        dhcp_rx_proxydhcpack ( dhcp, dhcpset );
                break;
        case DHCP_STATE_BSREQUEST:
                if ( ( msgtype == DHCPACK ) &&
-                    ( src_port == htons ( PROXYDHCP_PORT ) ) )
+                    ( src_port == htons ( PXE_PORT ) ) )
                        dhcp_rx_bsdhcpack ( dhcp, dhcpset );
                break;
        default: