[syslinux] [syslinux:firmware] efi: Add network support

[Gene Cumm]

On Thu, May 9, 2013 at 6:39 AM, syslinux-bot for Matt Fleming
<matt.fleming at intel.com> wrote:
> Commit-ID:  fe283b78c973268f2d1f0309826ceeb5c9e8978d
> Gitweb:     http://www.syslinux.org/commit/fe283b78c973268f2d1f0309826ceeb5c9e8978d
> Author:     Matt Fleming <matt.fleming at intel.com>
> AuthorDate: Fri, 22 Mar 2013 14:54:09 +0000
> Committer:  Matt Fleming <matt.fleming at intel.com>
> CommitDate: Tue, 23 Apr 2013 15:30:17 +0100
>
> efi: Add network support

> +/*
> + * This UDP binding is configured to operate in promiscuous mode. It is
> + * only used for reading packets. It has no associated state unlike
> + * socket->net.efi.binding, which has a remote IP address and port
> + * number.
> + */
> +static struct efi_binding *udp_reader;
> +
> +/**
> + * Open a socket
> + *
> + * @param:socket, the socket to open
> + *
> + * @out: error code, 0 on success, -1 on failure
> + */
> +int core_udp_open(struct pxe_pvt_inode *socket)
> +{

> +    memset(&udata, 0, sizeof(udata));
> +    udata.AcceptPromiscuous = TRUE;
> +    udata.AcceptAnyPort = TRUE;

Why promiscuous?  That seems to want to accept it on any local address
and put the NIC into promiscuous mode, avoiding the default MAC filter
in the NIC.  This should be uncessary as we're not capturinig.

> +/**
> + * Establish a connection on an open socket
> + *
> + * @param:socket, the open socket
> + * @param:ip, the ip address
> + * @param:port, the port number, host-byte order
> + */
> +void core_udp_connect(struct pxe_pvt_inode *socket, uint32_t ip,
> +                     uint16_t port)
> +{

> +    memcpy(&udata.StationAddress, &IPInfo.myip, sizeof(IPInfo.myip));
> +    memcpy(&udata.SubnetMask, &IPInfo.netmask, sizeof(IPInfo.netmask));
> +    memcpy(&udata.RemoteAddress, &ip, sizeof(ip));
> +    udata.RemotePort = port;
> +    udata.AcceptPromiscuous = TRUE;
> +

Looking at UEFI Spec v2.5 (same wording since the oldest 2.0 I have)
for EFI_UDP4_CONFIG_DATA, I could see now why an EFI implementer might
misinterpret the language and say that UseDefaultAddress is broken for
transmit even though my interpretation is that it will work for
transmit but is ignored for receive filtering.

-- 
-Gene