[ipv6] Extract link layer addresses from router advertisements

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/include/ipxe/icmpv6.h b/src/include/ipxe/icmpv6.h
index c09a71a023fc2608c7d4b4eb78d79808b2672609..15f8edd83fa1007636ef32ece4d1e7af71d64b29 100644 (file)
--- a/src/include/ipxe/icmpv6.h
+++ b/src/include/ipxe/icmpv6.h
@@ -46,11 +46,14 @@ struct icmpv6_handler {
 /** ICMPv6 echo reply */
 #define ICMPV6_ECHO_REPLY 129
 
+/** ICMPv6 router advertisement */
+#define ICMPV6_ROUTER_ADVERTISEMENT 134
+
 /** ICMPv6 neighbour solicitation */
-#define ICMPV6_NDP_NEIGHBOUR_SOLICITATION 135
+#define ICMPV6_NEIGHBOUR_SOLICITATION 135
 
 /** ICMPv6 neighbour advertisement */
-#define ICMPV6_NDP_NEIGHBOUR_ADVERTISEMENT 136
+#define ICMPV6_NEIGHBOUR_ADVERTISEMENT 136
 
 extern struct tcpip_protocol icmpv6_protocol __tcpip_protocol;
 

diff --git a/src/include/ipxe/ndp.h b/src/include/ipxe/ndp.h
index 1f05e9abeb76a82b6acb873a14ad829b7e5e1cfa..92f6da5921ca2920e34e124170b2c1a431799ee9 100644 (file)
--- a/src/include/ipxe/ndp.h
+++ b/src/include/ipxe/ndp.h
@@ -28,8 +28,8 @@ struct ndp_option {
 /** NDP option block size */
 #define NDP_OPTION_BLKSZ 8
 
-/** An NDP header */
-struct ndp_header {
+/** An NDP neighbour solicitation or advertisement header */
+struct ndp_neighbour_header {
        /** ICMPv6 header */
        struct icmp_header icmp;
        /** Flags */
@@ -43,13 +43,47 @@ struct ndp_header {
 } __attribute__ (( packed ));
 
 /** NDP router flag */
-#define NDP_ROUTER 0x80
+#define NDP_NEIGHBOUR_ROUTER 0x80
 
 /** NDP solicited flag */
-#define NDP_SOLICITED 0x40
+#define NDP_NEIGHBOUR_SOLICITED 0x40
 
 /** NDP override flag */
-#define NDP_OVERRIDE 0x20
+#define NDP_NEIGHBOUR_OVERRIDE 0x20
+
+/** An NDP router advertisement header */
+struct ndp_router_advertisement_header {
+       /** ICMPv6 header */
+       struct icmp_header icmp;
+       /** Current hop limit */
+       uint8_t hop_limit;
+       /** Flags */
+       uint8_t flags;
+       /** Router lifetime */
+       uint16_t lifetime;
+       /** Reachable time */
+       uint32_t reachable;
+       /** Retransmission timer */
+       uint32_t retransmit;
+       /** Options */
+       struct ndp_option option[0];
+} __attribute__ (( packed ));
+
+/** NDP managed address configuration */
+#define NDP_ROUTER_MANAGED 0x80
+
+/** NDP other configuration */
+#define NDP_ROUTER_OTHER 0x40
+
+/** An NDP header */
+union ndp_header {
+       /** ICMPv6 header */
+       struct icmp_header icmp;
+       /** Neighbour solicitation or advertisement header */
+       struct ndp_neighbour_header neigh;
+       /** Router advertisement header */
+       struct ndp_router_advertisement_header radv;
+} __attribute__ (( packed ));
 
 /** NDP source link-layer address option */
 #define NDP_OPT_LL_SOURCE 1

diff --git a/src/net/ndp.c b/src/net/ndp.c
index ee3a5b8b1b1514cca6a24366ecc29de8e4851d6f..b05756aa7c7658927aa86174dd90669859405120 100644 (file)
--- a/src/net/ndp.c
+++ b/src/net/ndp.c
@@ -61,34 +61,34 @@ static int ndp_tx_neighbour ( struct net_device *netdev,
                ( ( struct sockaddr_tcpip * ) sin6_dest );
        struct ll_protocol *ll_protocol = netdev->ll_protocol;
        struct io_buffer *iobuf;
-       struct ndp_header *ndp;
+       struct ndp_neighbour_header *neigh;
        size_t option_len;
        size_t len;
        int rc;
 
        /* Allocate and populate buffer */
-       option_len = ( ( sizeof ( ndp->option[0] ) + ll_protocol->ll_addr_len +
-                        NDP_OPTION_BLKSZ - 1 ) &
+       option_len = ( ( sizeof ( neigh->option[0] ) +
+                        ll_protocol->ll_addr_len + NDP_OPTION_BLKSZ - 1 ) &
                       ~( NDP_OPTION_BLKSZ - 1 ) );
-       len = ( sizeof ( *ndp ) + option_len );
+       len = ( sizeof ( *neigh ) + option_len );
        iobuf = alloc_iob ( MAX_LL_NET_HEADER_LEN + len );
        if ( ! iobuf )
                return -ENOMEM;
        iob_reserve ( iobuf, MAX_LL_NET_HEADER_LEN );
-       ndp = iob_put ( iobuf, len );
-       memset ( ndp, 0, len );
-       ndp->icmp.type = icmp_type;
-       ndp->flags = flags;
-       memcpy ( &ndp->target, target, sizeof ( ndp->target ) );
-       ndp->option[0].type = option_type;
-       ndp->option[0].blocks = ( option_len / NDP_OPTION_BLKSZ );
-       memcpy ( ndp->option[0].value, netdev->ll_addr,
+       neigh = iob_put ( iobuf, len );
+       memset ( neigh, 0, len );
+       neigh->icmp.type = icmp_type;
+       neigh->flags = flags;
+       memcpy ( &neigh->target, target, sizeof ( neigh->target ) );
+       neigh->option[0].type = option_type;
+       neigh->option[0].blocks = ( option_len / NDP_OPTION_BLKSZ );
+       memcpy ( neigh->option[0].value, netdev->ll_addr,
                 ll_protocol->ll_addr_len );
-       ndp->icmp.chksum = tcpip_chksum ( ndp, len );
+       neigh->icmp.chksum = tcpip_chksum ( neigh, len );
 
        /* Transmit packet */
        if ( ( rc = tcpip_tx ( iobuf, &icmpv6_protocol, st_src, st_dest,
-                              netdev, &ndp->icmp.chksum ) ) != 0 ) {
+                              netdev, &neigh->icmp.chksum ) ) != 0 ) {
                DBGC ( netdev, "NDP could not transmit packet: %s\n",
                       strerror ( rc ) );
                return rc;
@@ -127,7 +127,7 @@ static int ndp_tx_request ( struct net_device *netdev,
 
        /* Transmit neighbour discovery packet */
        return ndp_tx_neighbour ( netdev, &sin6_src, &sin6_dest, net_dest,
-                                 ICMPV6_NDP_NEIGHBOUR_SOLICITATION, 0,
+                                 ICMPV6_NEIGHBOUR_SOLICITATION, 0,
                                  NDP_OPT_LL_SOURCE );
 }
 
@@ -147,18 +147,20 @@ struct neighbour_discovery ndp_discovery = {
  * @v ll_addr_len      Source link-layer address length
  * @ret rc             Return status code
  */
-static int ndp_rx_neighbour_solicitation ( struct net_device *netdev,
-                                          struct sockaddr_in6 *sin6_src,
-                                          struct ndp_header *ndp __unused,
-                                          const void *ll_addr,
-                                          size_t ll_addr_len ) {
+static int
+ndp_rx_neighbour_solicitation_ll_source ( struct net_device *netdev,
+                                         struct sockaddr_in6 *sin6_src,
+                                         union ndp_header *ndp,
+                                         const void *ll_addr,
+                                         size_t ll_addr_len ) {
+       struct ndp_neighbour_header *neigh = &ndp->neigh;
        struct ll_protocol *ll_protocol = netdev->ll_protocol;
        int rc;
 
        /* Silently ignore neighbour solicitations for addresses we do
         * not own.
         */
-       if ( ! ipv6_has_addr ( netdev, &ndp->target ) )
+       if ( ! ipv6_has_addr ( netdev, &neigh->target ) )
                return 0;
 
        /* Sanity check */
@@ -180,9 +182,10 @@ static int ndp_rx_neighbour_solicitation ( struct net_device *netdev,
        }
 
        /* Send neighbour advertisement */
-       if ( ( rc = ndp_tx_neighbour ( netdev, NULL, sin6_src, &ndp->target,
-                                      ICMPV6_NDP_NEIGHBOUR_ADVERTISEMENT,
-                                      ( NDP_SOLICITED | NDP_OVERRIDE ),
+       if ( ( rc = ndp_tx_neighbour ( netdev, NULL, sin6_src, &neigh->target,
+                                      ICMPV6_NEIGHBOUR_ADVERTISEMENT,
+                                      ( NDP_NEIGHBOUR_SOLICITED |
+                                        NDP_NEIGHBOUR_OVERRIDE ),
                                       NDP_OPT_LL_TARGET ) ) != 0 ) {
                return rc;
        }
@@ -201,10 +204,13 @@ static int ndp_rx_neighbour_solicitation ( struct net_device *netdev,
  * @ret rc             Return status code
  */
 static int
-ndp_rx_neighbour_advertisement ( struct net_device *netdev,
-                                struct sockaddr_in6 *sin6_src __unused,
-                                struct ndp_header *ndp, const void *ll_addr,
-                                size_t ll_addr_len ) {
+ndp_rx_neighbour_advertisement_ll_target ( struct net_device *netdev,
+                                          struct sockaddr_in6 *sin6_src
+                                                  __unused,
+                                          union ndp_header *ndp,
+                                          const void *ll_addr,
+                                          size_t ll_addr_len ) {
+       struct ndp_neighbour_header *neigh = &ndp->neigh;
        struct ll_protocol *ll_protocol = netdev->ll_protocol;
        int rc;
 
@@ -217,10 +223,50 @@ ndp_rx_neighbour_advertisement ( struct net_device *netdev,
        }
 
        /* Update neighbour cache entry, if any */
-       if ( ( rc = neighbour_update ( netdev, &ipv6_protocol, &ndp->target,
+       if ( ( rc = neighbour_update ( netdev, &ipv6_protocol, &neigh->target,
                                       ll_addr ) ) != 0 ) {
                DBGC ( netdev, "NDP could not update %s => %s: %s\n",
-                      inet6_ntoa ( &ndp->target ),
+                      inet6_ntoa ( &neigh->target ),
+                      ll_protocol->ntoa ( ll_addr ), strerror ( rc ) );
+               return rc;
+       }
+
+       return 0;
+}
+
+/**
+ * Process NDP router advertisement source link-layer address option
+ *
+ * @v netdev           Network device
+ * @v sin6_src         Source socket address
+ * @v ndp              NDP packet
+ * @v ll_addr          Target link-layer address
+ * @v ll_addr_len      Target link-layer address length
+ * @ret rc             Return status code
+ */
+static int
+ndp_rx_router_advertisement_ll_source ( struct net_device *netdev,
+                                       struct sockaddr_in6 *sin6_src,
+                                       union ndp_header *ndp __unused,
+                                       const void *ll_addr,
+                                       size_t ll_addr_len ) {
+       struct ll_protocol *ll_protocol = netdev->ll_protocol;
+       int rc;
+
+       /* Sanity check */
+       if ( ll_addr_len < ll_protocol->ll_addr_len ) {
+               DBGC ( netdev, "NDP router advertisement link-layer address "
+                      "too short at %zd bytes (min %d bytes)\n",
+                      ll_addr_len, ll_protocol->ll_addr_len );
+               return -EINVAL;
+       }
+
+       /* Define neighbour cache entry */
+       if ( ( rc = neighbour_define ( netdev, &ipv6_protocol,
+                                      &sin6_src->sin6_addr,
+                                      ll_addr ) ) != 0 ) {
+               DBGC ( netdev, "NDP could not define %s => %s: %s\n",
+                      inet6_ntoa ( &sin6_src->sin6_addr ),
                       ll_protocol->ntoa ( ll_addr ), strerror ( rc ) );
                return rc;
        }
@@ -245,20 +291,25 @@ struct ndp_option_handler {
         * @ret rc              Return status code
         */
        int ( * rx ) ( struct net_device *netdev, struct sockaddr_in6 *sin6_src,
-                      struct ndp_header *ndp, const void *value, size_t len );
+                      union ndp_header *ndp, const void *value, size_t len );
 };
 
 /** NDP option handlers */
 static struct ndp_option_handler ndp_option_handlers[] = {
        {
-               .icmp_type = ICMPV6_NDP_NEIGHBOUR_SOLICITATION,
+               .icmp_type = ICMPV6_NEIGHBOUR_SOLICITATION,
                .option_type = NDP_OPT_LL_SOURCE,
-               .rx = ndp_rx_neighbour_solicitation,
+               .rx = ndp_rx_neighbour_solicitation_ll_source,
        },
        {
-               .icmp_type = ICMPV6_NDP_NEIGHBOUR_ADVERTISEMENT,
+               .icmp_type = ICMPV6_NEIGHBOUR_ADVERTISEMENT,
                .option_type = NDP_OPT_LL_TARGET,
-               .rx = ndp_rx_neighbour_advertisement,
+               .rx = ndp_rx_neighbour_advertisement_ll_target,
+       },
+       {
+               .icmp_type = ICMPV6_ROUTER_ADVERTISEMENT,
+               .option_type = NDP_OPT_LL_SOURCE,
+               .rx = ndp_rx_router_advertisement_ll_source,
        },
 };
 
@@ -275,7 +326,7 @@ static struct ndp_option_handler ndp_option_handlers[] = {
  */
 static int ndp_rx_option ( struct net_device *netdev,
                           struct sockaddr_in6 *sin6_src,
-                          struct ndp_header *ndp, unsigned int type,
+                          union ndp_header *ndp, unsigned int type,
                           const void *value, size_t len ) {
        struct ndp_option_handler *handler;
        unsigned int i;
@@ -301,14 +352,14 @@ static int ndp_rx_option ( struct net_device *netdev,
  * @v iobuf            I/O buffer
  * @v netdev           Network device
  * @v sin6_src         Source socket address
- * @v sin6_dest                Destination socket address
+ * @v offset           Offset to NDP options
  * @ret rc             Return status code
  */
 static int ndp_rx ( struct io_buffer *iobuf,
                    struct net_device *netdev,
                    struct sockaddr_in6 *sin6_src,
-                   struct sockaddr_in6 *sin6_dest __unused ) {
-       struct ndp_header *ndp = iobuf->data;
+                   size_t offset ) {
+       union ndp_header *ndp = iobuf->data;
        struct ndp_option *option;
        size_t remaining;
        size_t option_len;
@@ -316,16 +367,16 @@ static int ndp_rx ( struct io_buffer *iobuf,
        int rc;
 
        /* Sanity check */
-       if ( iob_len ( iobuf ) < sizeof ( *ndp ) ) {
+       if ( iob_len ( iobuf ) < offset ) {
                DBGC ( netdev, "NDP packet too short at %zd bytes (min %zd "
-                      "bytes)\n", iob_len ( iobuf ), sizeof ( *ndp ) );
+                      "bytes)\n", iob_len ( iobuf ), offset );
                rc = -EINVAL;
                goto done;
        }
 
        /* Search for option */
-       option = ndp->option;
-       remaining = ( iob_len ( iobuf ) - offsetof ( typeof ( *ndp ), option ));
+       option = ( ( ( void * ) ndp ) + offset );
+       remaining = ( iob_len ( iobuf ) - offset );
        while ( remaining ) {
 
                /* Sanity check */
@@ -360,14 +411,60 @@ static int ndp_rx ( struct io_buffer *iobuf,
        return rc;
 }
 
+/**
+ * Process received NDP neighbour solicitation or advertisement
+ *
+ * @v iobuf            I/O buffer
+ * @v netdev           Network device
+ * @v sin6_src         Source socket address
+ * @v sin6_dest                Destination socket address
+ * @ret rc             Return status code
+ */
+static int ndp_rx_neighbour ( struct io_buffer *iobuf,
+                             struct net_device *netdev,
+                             struct sockaddr_in6 *sin6_src,
+                             struct sockaddr_in6 *sin6_dest __unused ) {
+       union ndp_header *ndp = iobuf->data;
+       struct ndp_neighbour_header *neigh = &ndp->neigh;
+
+       return ndp_rx ( iobuf, netdev, sin6_src,
+                       offsetof ( typeof ( *neigh ), option ) );
+}
+
+/**
+ * Process received NDP router advertisement
+ *
+ * @v iobuf            I/O buffer
+ * @v netdev           Network device
+ * @v sin6_src         Source socket address
+ * @v sin6_dest                Destination socket address
+ * @ret rc             Return status code
+ */
+static int
+ndp_rx_router_advertisement ( struct io_buffer *iobuf,
+                             struct net_device *netdev,
+                             struct sockaddr_in6 *sin6_src,
+                             struct sockaddr_in6 *sin6_dest __unused ) {
+       union ndp_header *ndp = iobuf->data;
+       struct ndp_router_advertisement_header *radv = &ndp->radv;
+
+       return ndp_rx ( iobuf, netdev, sin6_src,
+                       offsetof ( typeof ( *radv ), option ) );
+}
+
+
 /** NDP ICMPv6 handlers */
 struct icmpv6_handler ndp_handlers[] __icmpv6_handler = {
        {
-               .type = ICMPV6_NDP_NEIGHBOUR_SOLICITATION,
-               .rx = ndp_rx,
+               .type = ICMPV6_NEIGHBOUR_SOLICITATION,
+               .rx = ndp_rx_neighbour,
+       },
+       {
+               .type = ICMPV6_NEIGHBOUR_ADVERTISEMENT,
+               .rx = ndp_rx_neighbour,
        },
        {
-               .type = ICMPV6_NDP_NEIGHBOUR_ADVERTISEMENT,
-               .rx = ndp_rx,
+               .type = ICMPV6_ROUTER_ADVERTISEMENT,
+               .rx = ndp_rx_router_advertisement,
        },
 };