iPXE was unable to receive priority tagged packets specified in
the 802.1Q standard and supported by all major networking stacks.
This commit adds a new function net_pull_tags which is called by
all consumers of incoming packets after stripping their link-layer
headers.
Signed-off-by: Ladi Prosek <lpro...@redhat.com>
---
This is another attempt at implementing the VLAN 0 feature. It is
always enabled and independent of the true VLAN_CMD support, as
discussed before. All code paths that process incoming packets now
strip VLAN 0 headers.
If VLAN 0 was Ethernet only, it would conceptually belong in eth_pull.
Since it's "link-layer-independent", I took the liberty to create
a new function to be called between handling the link layer and
network layer headers. Thanks!
src/arch/x86/interface/pxe/pxe_undi.c | 6 +++++
src/include/ipxe/netdevice.h | 2 ++
src/interface/efi/efi_snp.c | 7 ++++++
src/net/netdevice.c | 44 +++++++++++++++++++++++++++++++++++
4 files changed, 59 insertions(+)
diff --git a/src/arch/x86/interface/pxe/pxe_undi.c
b/src/arch/x86/interface/pxe/pxe_undi.c
index 2eb6817..2ea1451 100644
--- a/src/arch/x86/interface/pxe/pxe_undi.c
+++ b/src/arch/x86/interface/pxe/pxe_undi.c
@@ -976,6 +976,12 @@ static PXENV_EXIT_t pxenv_undi_isr ( struct
s_PXENV_UNDI_ISR *undi_isr ) {
}
ll_hlen = ( len - iob_len ( iobuf ) );
+ /* Strip link-layer-independent headers */
+ if ( ( rc = net_pull_tags ( iobuf, pxe_netdev, &net_proto ) )
!= 0 ) {
+ /* Assume unknown net_proto */
+ net_proto = 0;
+ }
+
/* Determine network-layer protocol */
switch ( net_proto ) {
case htons ( ETH_P_IP ):
diff --git a/src/include/ipxe/netdevice.h b/src/include/ipxe/netdevice.h
index a1d207f..cea87f7 100644
--- a/src/include/ipxe/netdevice.h
+++ b/src/include/ipxe/netdevice.h
@@ -719,6 +719,8 @@ extern int net_tx ( struct io_buffer *iobuf, struct
net_device *netdev,
extern int net_rx ( struct io_buffer *iobuf, struct net_device *netdev,
uint16_t net_proto, const void *ll_dest,
const void *ll_source, unsigned int flags );
+extern int net_pull_tags ( struct io_buffer *iobuf, struct net_device *netdev,
+ uint16_t *net_proto );
extern void net_poll ( void );
extern struct net_device_configurator *
find_netdev_configurator ( const char *name );
diff --git a/src/interface/efi/efi_snp.c b/src/interface/efi/efi_snp.c
index e6388bf..d1a1a44 100644
--- a/src/interface/efi/efi_snp.c
+++ b/src/interface/efi/efi_snp.c
@@ -745,6 +745,13 @@ efi_snp_receive ( EFI_SIMPLE_NETWORK_PROTOCOL *snp,
goto out_bad_ll_header;
}
+ /* Strip link-layer-independent headers */
+ if ( ( rc = net_pull_tags ( iobuf, snpdev->netdev, &iob_net_proto ) ) )
{
+ DBGC ( snpdev, "SNPDEV %p could not parse tags: %s\n",
+ snpdev, strerror ( rc ) );
+ goto out_bad_ll_header;
+ }
+
/* Return link-layer header parameters to caller, if required */
if ( ll_header_len )
*ll_header_len = ll_protocol->ll_header_len;
diff --git a/src/net/netdevice.c b/src/net/netdevice.c
index 9df2119..c53d5e3 100644
--- a/src/net/netdevice.c
+++ b/src/net/netdevice.c
@@ -1028,6 +1028,44 @@ int net_rx ( struct io_buffer *iobuf, struct net_device
*netdev,
}
/**
+ * Strip extra link-layer-independent tags from a received packet
+ *
+ * @v iobuf I/O buffer
+ * @v netdev Network device
+ * @v net_proto Network-layer protocol, in network-byte order
+ * @ret rc Return status code
+ *
+ * This function should be called after stripping link-layer headers but
+ * before inspecting the network-layer protocol.
+ */
+int net_pull_tags ( struct io_buffer *iobuf, struct net_device *netdev,
+ uint16_t *net_proto ) {
+ struct vlan_header *vlanhdr;
+ uint16_t tag;
+
+ /* Strip 802.1Q VLAN 0 priority tags if present */
+ while ( *net_proto == htons ( ETH_P_8021Q ) ) {
+ if ( iob_len ( iobuf ) < sizeof ( *vlanhdr ) ) {
+ DBG ( "VLAN header too short at %zd bytes (min %zd
bytes)\n",
+ iob_len ( iobuf ), sizeof ( *vlanhdr ) );
+ return -EINVAL;
+ }
+ vlanhdr = ( struct vlan_header * ) iobuf->data;
+ tag = VLAN_TAG ( ntohs ( vlanhdr->tci ) );
+
+ if ( tag == 0 && ! vlan_find ( netdev, tag ) ) {
+ /* VLAN 0, strip and continue */
+ *net_proto = vlanhdr->net_proto;
+ iob_pull ( iobuf, sizeof ( *vlanhdr ) );
+ } else {
+ /* Real VLAN tag, leave it alone */
+ break;
+ }
+ }
+ return 0;
+}
+
+/**
* Poll the network stack
*
* This polls all interfaces for received packets, and processes
@@ -1078,6 +1116,12 @@ void net_poll ( void ) {
continue;
}
+ /* Remove link-layer-independent headers */
+ if ( ( rc = net_pull_tags ( iobuf, netdev, &net_proto )
) ) {
+ free_iob ( iobuf );
+ continue;
+ }
+
/* Hand packet to network layer */
if ( ( rc = net_rx ( iob_disown ( iobuf ), netdev,
net_proto, ll_dest,
--
2.5.5
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