[PATCH net,1/1] hyperv: Add support for setting MAC from within guests
From: Haiyang Zhang <haiyangz@microsoft.com>
Date: 2012-07-06 21:11:49
This adds support for setting synthetic NIC MAC address from within Linux guests. Before using this feature, the option "spoofing of MAC address" should be enabled at the Hyper-V manager / Settings of the synthetic NIC. Thanks to Kin Cho [off-list ref] for the initial implementation and tests. And, thanks to Long Li [off-list ref] for the debugging works. Reported-and-tested-by: Kin Cho <redacted> Reported-by: Long Li <longli@microsoft.com> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> --- drivers/net/hyperv/hyperv_net.h | 1 + drivers/net/hyperv/netvsc_drv.c | 30 +++++++++++++- drivers/net/hyperv/rndis_filter.c | 79 +++++++++++++++++++++++++++++++++++++ 3 files changed, 109 insertions(+), 1 deletions(-)
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 2857ab0..95ceb35 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h@@ -131,6 +131,7 @@ int rndis_filter_send(struct hv_device *dev, struct hv_netvsc_packet *pkt); int rndis_filter_set_packet_filter(struct rndis_device *dev, u32 new_filter); +int rndis_filter_set_device_mac(struct hv_device *hdev, char *mac); #define NVSP_INVALID_PROTOCOL_VERSION ((u32)0xFFFFFFFF)
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 8f8ed33..8e23c08 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c@@ -341,6 +341,34 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu) return 0; } + +static int netvsc_set_mac_addr(struct net_device *ndev, void *p) +{ + struct net_device_context *ndevctx = netdev_priv(ndev); + struct hv_device *hdev = ndevctx->device_ctx; + struct sockaddr *addr = p; + char save_adr[14]; + unsigned char save_aatype; + int err; + + memcpy(save_adr, ndev->dev_addr, ETH_ALEN); + save_aatype = ndev->addr_assign_type; + + err = eth_mac_addr(ndev, p); + if (err != 0) + return err; + + err = rndis_filter_set_device_mac(hdev, addr->sa_data); + if (err != 0) { + /* roll back to saved MAC */ + memcpy(ndev->dev_addr, save_adr, ETH_ALEN); + ndev->addr_assign_type = save_aatype; + } + + return err; +} + + static const struct ethtool_ops ethtool_ops = { .get_drvinfo = netvsc_get_drvinfo, .get_link = ethtool_op_get_link,
@@ -353,7 +381,7 @@ static const struct net_device_ops device_ops = { .ndo_set_rx_mode = netvsc_set_multicast_list, .ndo_change_mtu = netvsc_change_mtu, .ndo_validate_addr = eth_validate_addr, - .ndo_set_mac_address = eth_mac_addr, + .ndo_set_mac_address = netvsc_set_mac_addr, }; /*
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index 981ebb1..fbf5394 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c@@ -27,6 +27,7 @@ #include <linux/if_ether.h> #include <linux/netdevice.h> #include <linux/if_vlan.h> +#include <linux/nls.h> #include "hyperv_net.h"
@@ -47,6 +48,7 @@ struct rndis_request { struct hv_page_buffer buf; /* FIXME: We assumed a fixed size request here. */ struct rndis_message request_msg; + u8 ext[100]; }; static void rndis_filter_send_completion(void *ctx);
@@ -511,6 +513,83 @@ static int rndis_filter_query_device_mac(struct rndis_device *dev) dev->hw_mac_adr, &size); } +#define NWADR_STR "NetworkAddress" +#define NWADR_STRLEN 14 + +int rndis_filter_set_device_mac(struct hv_device *hdev, char *mac) +{ + struct netvsc_device *nvdev = hv_get_drvdata(hdev); + struct rndis_device *rdev = nvdev->extension; + struct net_device *ndev = nvdev->ndev; + struct rndis_request *request; + struct rndis_set_request *set; + struct rndis_config_parameter_info *cpi; + wchar_t *cfg_nwadr, *cfg_mac; + struct rndis_set_complete *set_complete; + char macstr[2*ETH_ALEN+1]; + u32 extlen = sizeof(struct rndis_config_parameter_info) + + 2*NWADR_STRLEN + 4*ETH_ALEN; + int ret, t; + + request = get_rndis_request(rdev, RNDIS_MSG_SET, + RNDIS_MESSAGE_SIZE(struct rndis_set_request) + extlen); + if (!request) + return -ENOMEM; + + set = &request->request_msg.msg.set_req; + set->oid = RNDIS_OID_GEN_RNDIS_CONFIG_PARAMETER; + set->info_buflen = extlen; + set->info_buf_offset = sizeof(struct rndis_set_request); + set->dev_vc_handle = 0; + + cpi = (struct rndis_config_parameter_info *)((ulong)set + + set->info_buf_offset); + cpi->parameter_name_offset = + sizeof(struct rndis_config_parameter_info); + /* Multiply by 2 because host needs 2 bytes (utf16) for each char */ + cpi->parameter_name_length = 2*NWADR_STRLEN; + cpi->parameter_type = RNDIS_CONFIG_PARAM_TYPE_STRING; + cpi->parameter_value_offset = + cpi->parameter_name_offset + cpi->parameter_name_length; + /* Multiply by 4 because each MAC byte displayed as 2 utf16 chars */ + cpi->parameter_value_length = 4*ETH_ALEN; + + cfg_nwadr = (wchar_t *)((ulong)cpi + cpi->parameter_name_offset); + cfg_mac = (wchar_t *)((ulong)cpi + cpi->parameter_value_offset); + ret = utf8s_to_utf16s(NWADR_STR, NWADR_STRLEN, UTF16_HOST_ENDIAN, + cfg_nwadr, NWADR_STRLEN); + if (ret < 0) + goto cleanup; + snprintf(macstr, 2*ETH_ALEN+1, "%pm", mac); + ret = utf8s_to_utf16s(macstr, 2*ETH_ALEN, UTF16_HOST_ENDIAN, + cfg_mac, 2*ETH_ALEN); + if (ret < 0) + goto cleanup; + + ret = rndis_filter_send_request(rdev, request); + if (ret != 0) + goto cleanup; + + t = wait_for_completion_timeout(&request->wait_event, 5*HZ); + if (t == 0) { + netdev_err(ndev, "timeout before we got a set response...\n"); + /* + * can't put_rndis_request, since we may still receive a + * send-completion. + */ + return -EBUSY; + } else { + set_complete = &request->response_msg.msg.set_complete; + if (set_complete->status != RNDIS_STATUS_SUCCESS) + ret = -EINVAL; + } + +cleanup: + put_rndis_request(rdev, request); + return ret; +} + + static int rndis_filter_query_device_link_status(struct rndis_device *dev) { u32 size = sizeof(u32);
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1.7.4.1