From 5b4746fd6be68bb0b773d9830275fbee7dbdab66 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Sun, 1 Sep 2019 17:17:53 +0200 Subject: [PATCH] efi_loader: implement MCastIPtoMAC Implement the MCastIPtoMAC service of the simple network protocol. It converts an multicast IPv4 (or IPv6) address to a multicast Ethernet address. Signed-off-by: Heinrich Schuchardt --- lib/efi_loader/efi_net.c | 44 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 42 insertions(+), 2 deletions(-) diff --git a/lib/efi_loader/efi_net.c b/lib/efi_loader/efi_net.c index 66c1898940..cff6332a68 100644 --- a/lib/efi_loader/efi_net.c +++ b/lib/efi_loader/efi_net.c @@ -332,7 +332,7 @@ static efi_status_t EFIAPI efi_net_statistics(struct efi_simple_network *this, /* * efi_net_mcastiptomac() - translate multicast IP address to MAC address * - * This function implements the Statistics service of the + * This function implements the MCastIPtoMAC service of the * EFI_SIMPLE_NETWORK_PROTOCOL. See the Unified Extensible Firmware Interface * (UEFI) specification for details. * @@ -347,9 +347,49 @@ static efi_status_t EFIAPI efi_net_mcastiptomac(struct efi_simple_network *this, struct efi_ip_address *ip, struct efi_mac_address *mac) { + efi_status_t ret = EFI_SUCCESS; + EFI_ENTRY("%p, %x, %p, %p", this, ipv6, ip, mac); - return EFI_EXIT(EFI_INVALID_PARAMETER); + if (!this || !ip || !mac) { + ret = EFI_INVALID_PARAMETER; + goto out; + } + + if (ipv6) { + ret = EFI_UNSUPPORTED; + goto out; + } + + /* Multi-cast addresses are in the range 224.0.0.0 - 239.255.255.255 */ + if ((ip->ip_addr[0] & 0xf0) != 0xe0) { + ret = EFI_INVALID_PARAMETER; + goto out; + }; + + switch (this->mode->state) { + case EFI_NETWORK_INITIALIZED: + case EFI_NETWORK_STARTED: + break; + default: + ret = EFI_NOT_STARTED; + goto out; + } + + memset(mac, 0, sizeof(struct efi_mac_address)); + + /* + * Copy lower 23 bits of IPv4 multi-cast address + * RFC 1112, RFC 7042 2.1.1. + */ + mac->mac_addr[0] = 0x01; + mac->mac_addr[1] = 0x00; + mac->mac_addr[2] = 0x5E; + mac->mac_addr[3] = ip->ip_addr[1] & 0x7F; + mac->mac_addr[4] = ip->ip_addr[2]; + mac->mac_addr[5] = ip->ip_addr[3]; +out: + return EFI_EXIT(ret); } /** -- 2.39.5