/*
* An implementation of key value pair (KVP) functionality for Linux.
*
*
* Copyright (C) 2010, Novell, Inc.
* Author : K. Y. Srinivasan <ksrinivasan@novell.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/net.h>
#include <linux/nls.h>
#include <linux/connector.h>
#include <linux/workqueue.h>
#include <linux/hyperv.h>
/*
* Pre win8 version numbers used in ws2008 and ws 2008 r2 (win7)
*/
#define WS2008_SRV_MAJOR 1
#define WS2008_SRV_MINOR 0
#define WS2008_SRV_VERSION (WS2008_SRV_MAJOR << 16 | WS2008_SRV_MINOR)
#define WIN7_SRV_MAJOR 3
#define WIN7_SRV_MINOR 0
#define WIN7_SRV_VERSION (WIN7_SRV_MAJOR << 16 | WIN7_SRV_MINOR)
#define WIN8_SRV_MAJOR 4
#define WIN8_SRV_MINOR 0
#define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
/*
* Global state maintained for transaction that is being processed.
* Note that only one transaction can be active at any point in time.
*
* This state is set when we receive a request from the host; we
* cleanup this state when the transaction is completed - when we respond
* to the host with the key value.
*/
static struct {
bool active; /* transaction status - active or not */
int recv_len; /* number of bytes received. */
struct hv_kvp_msg *kvp_msg; /* current message */
struct vmbus_channel *recv_channel; /* chn we got the request */
u64 recv_req_id; /* request ID. */
void *kvp_context; /* for the channel callback */
} kvp_transaction;
/*
* Before we can accept KVP messages from the host, we need
* to handshake with the user level daemon. This state tracks
* if we are in the handshake phase.
*/
static bool in_hand_shake = true;
/*
* This state maintains the version number registered by the daemon.
*/
static int dm_reg_value;
static void kvp_send_key(struct work_struct *dummy);
static void kvp_respond_to_host(struct hv_kvp_msg *msg, int error);
static void kvp_work_func(struct work_struct *dummy);
static void kvp_register(int);
static DECLARE_DELAYED_WORK(kvp_work, kvp_work_func);
static DECLARE_WORK(kvp_sendkey_work, kvp_send_key);
static struct cb_id kvp_id = { CN_KVP_IDX, CN_KVP_VAL };
static const char kvp_name[] = "kvp_kernel_module";
static u8 *recv_buffer;
/*
* Register the kernel component with the user-level daemon.
* As part of this registration, pass the LIC version number.
* This number has no meaning, it satisfies the registration protocol.
*/
#define HV_DRV_VERSION "3.1"
static void
kvp_register(int reg_value)
{
struct cn_msg *msg;
struct hv_kvp_msg *kvp_msg;
char *version;
msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg), GFP_ATOMIC);
if (msg) {
kvp_msg = (struct hv_kvp_msg *)msg->data;
version = kvp_msg->body.kvp_register.version;
msg->id.idx = CN_KVP_IDX;
msg->id.val = CN_KVP_VAL;
kvp_msg->kvp_hdr.operation = reg_value;
strcpy(version, HV_DRV_VERSION);
msg->len = sizeof(struct hv_kvp_msg);
cn_netlink_send(msg, 0, GFP_ATOMIC);
kfree(msg);
}
}
static void
kvp_work_func(struct work_struct *dummy)
{
/*
* If the timer fires, the user-mode component has not responded;
* process the pending transaction.
*/
kvp_respond_to_host(NULL, HV_E_FAIL);
}
static int kvp_handle_handshake(struct hv_kvp_msg *msg)
{
int ret = 1;
switch (msg->kvp_hdr.operation) {
case KVP_OP_REGISTER:
dm_reg_value = KVP_OP_REGISTER;
pr_info("KVP: IP injection functionality not available\n");
pr_info("KVP: Upgrade the KVP daemon\n");
break;
case KVP_OP_REGISTER1:
dm_reg_value = KVP_OP_REGISTER1;
break;
default:
pr_info("KVP: incompatible daemon\n");
pr_info("KVP: KVP version: %d, Daemon version: %d\n",
KVP_OP_REGISTER1, msg->kvp_hdr.operation);
ret = 0;
}
if (ret) {
/*
* We have a compatible daemon; complete the handshake.
*/
pr_info("KVP: user-mode registering done.\n");
kvp_register(dm_reg_value);
kvp_transaction.active = false;
if (kvp_transaction.kvp_context)
hv_kvp_onchannelcallback(kvp_transaction.kvp_context);
}
return ret;
}
/*
* Callback when data is received from user mode.
*/
static void
kvp_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{
struct hv_kvp_msg *message;
struct hv_kvp_msg_enumerate *data;
int error = 0;
message = (struct hv_kvp_msg *)msg->data;
/*
* If we are negotiating the version information
* with the daemon; handle that first.
*/
if (in_hand_shake) {
if (kvp_handle_handshake(message))
in_hand_shake = false;
return;
}
/*
* Based on the version of the daemon, we propagate errors from the
* daemon differently.
*/
data = &message->body.kvp_enum_data;
switch (dm_reg_value) {
case KVP_OP_REGISTER:
/*
* Null string is used to pass back error condition.
*/
if (data->data.key[0] == 0)
error = HV_S_CONT;
break;
case KVP_OP_REGISTER1:
/*
* We use the message header information from
* the user level daemon to transmit errors.
*/
error = message->error;
break;
}
/*
* Complete the transaction by forwarding the key value
* to the host. But first, cancel the timeout.
*/
if (cancel_delayed_work_sync(&kvp_work))
kvp_respond_to_host(message, error);
}
static int process_ob_ipinfo(void *in_msg, void *out_msg, int op)
{
struct hv_kvp_msg *in = in_msg;
struct hv_kvp_ip_msg *out = out_msg;
int len;
switch (op) {
case KVP_OP_GET_IP_INFO:
/*
* Transform all parameters into utf16 encoding.
*/
len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.ip_addr,
strlen((char *)in->body.kvp_ip_val.ip_addr),
UTF16_HOST_ENDIAN,
(wchar_t *)out->kvp_ip_val.ip_addr,
MAX_IP_ADDR_SIZE);
if (len < 0)
return len;
len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.sub_net,
strlen((char *)in->body.kvp_ip_val.sub_net),
UTF16_HOST_ENDIAN,
(wchar_t *)out->kvp_ip_val.sub_net,
MAX_IP_ADDR_SIZE);
if (len < 0)
return len;
len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.gate_way,
strlen((char *)in->body.kvp_ip_val.gate_way),
UTF16_HOST_ENDIAN,
(wchar_t *)out->kvp_ip_val.gate_way,
MAX_GATEWAY_SIZE);
if (len < 0)
return len;
len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.dns_addr,
strlen((char *)in->body.kvp_ip_val.dns_addr),
UTF16_HOST_ENDIAN,
(wchar_t *)out->kvp_ip_val.dns_addr,
MAX_IP_ADDR_SIZE);
if (len < 0)
return len;
len = utf8s_to_utf16s((char *)in->body.kvp_ip_val.adapter_id,
strlen((char *)in->body.kvp_ip_val.adapter_id),
UTF16_HOST_ENDIAN,
(wchar_t *)out->kvp_ip_val.adapter_id,
MAX_IP_ADDR_SIZE);
if (len < 0)
return len;
out->kvp_ip_val.dhcp_enabled =
in->body.kvp_ip_val.dhcp_enabled;
out->kvp_ip_val.addr_family =
in->body.kvp_ip_val.addr_family;
}
return 0;
}
static void process_ib_ipinfo(void *in_msg, void *out_msg, int op)
{
struct hv_kvp_ip_msg *in = in_msg;
struct hv_kvp_msg *out = out_msg;
switch (op) {
case KVP_OP_SET_IP_INFO:
/*
* Transform all parameters into utf8 encoding.
*/
utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.ip_addr,
MAX_IP_ADDR_SIZE,
UTF16_LITTLE_ENDIAN,
(__u8 *)out->body.kvp_ip_val.ip_addr,
MAX_IP_ADDR_SIZE);
utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.sub_net,
MAX_IP_ADDR_SIZE,
UTF16_LITTLE_ENDIAN,
(__u8 *)out->body.kvp_ip_val.sub_net,
MAX_IP_ADDR_SIZE);
utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.gate_way,
MAX_GATEWAY_SIZE,
UTF16_LITTLE_ENDIAN,
(__u8 *)out->body.kvp_ip_val.gate_way,
MAX_GATEWAY_SIZE);
utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.dns_addr,
MAX_IP_ADDR_SIZE,
UTF16_LITTLE_ENDIAN,
(__u8 *)out->body.kvp_ip_val.dns_addr,
MAX_IP_ADDR_SIZE);
out->body.kvp_ip_val.dhcp_enabled = in->kvp_ip_val.dhcp_enabled;
default:
utf16s_to_utf8s((wchar_t *)in->kvp_ip_val.adapter_id,
MAX_ADAPTER_ID_SIZE,
UTF16_LITTLE_ENDIAN,
(__u8 *)out->body.kvp_ip_val.adapter_id,
MAX_ADAPTER_ID_SIZE);
out->body.kvp_ip_val.addr_family = in->kvp_ip_val.addr_family;
}
}
static void
kvp_send_key(struct work_struct *dummy)
{
struct cn_msg *msg;
struct hv_kvp_msg *message;
struct hv_kvp_msg *in_msg;
__u8 operation = kvp_transaction.kvp_msg->kvp_hdr.operation;
__u8 pool = kvp_transaction.kvp_msg->kvp_hdr.pool;
__u32 val32;
__u64 val64;
msg = kzalloc(sizeof(*msg) + sizeof(struct hv_kvp_msg) , GFP_ATOMIC);
if (!msg)
return;
msg->id.idx = CN_KVP_IDX;
msg->id.val = CN_KVP_VAL;
message = (struct hv_kvp_msg *)msg->data;
message->kvp_hdr.operation = operation;
message->kvp_hdr.pool = pool;
in_msg = kvp_transaction.kvp_msg;
/*
* The key/value strings sent from the host are encoded in
* in utf16; convert it to utf8 strings.
* The host assures us that the utf16 strings will not exceed
* the max lengths specified. We will however, reserve room
* for the string terminating character - in the utf16s_utf8s()
* function we limit the size of the buffer where the converted
* string is placed to HV_KVP_EXCHANGE_MAX_*_SIZE -1 to gaurantee
* that the strings can be properly terminated!
*/
switch (message->kvp_hdr.operation) {
case KVP_OP_SET_IP_INFO:
process_ib_ipinfo(in_msg, message, KVP_OP_SET_IP_INFO);
break;
case KVP_OP_GET_IP_INFO:
process_ib_ipinfo(in_msg, message, KVP_OP_GET_IP_INFO);
break;
case KVP_OP_SET:
switch (in_msg->body.kvp_set.data.value_type) {
case REG_SZ:
/*
* The value is a string - utf16 encoding.
*/
message->body.kvp_set.data.value_size =
utf16s_to_utf8s(
(wchar_t *)in_msg->body.kvp_set.data.value,
in_msg->body.kvp_set.data.value_size,
UTF16_LITTLE_ENDIAN,
message->body.kvp_set.data.value,
HV_KVP_EXCHANGE_MAX_VALUE_SIZE - 1) + 1;
break;
case REG_U32:
/*
* The value is a 32 bit scalar.
* We save this as a utf8 string.
*/
val32 = in_msg->body.kvp_set.data.value_u32;
message->body.kvp_set.data.value_size =
sprintf(message->body.kvp_set.data.value,
"%d", val32) + 1;
break;
case REG_U64:
/*
* The value is a 64 bit scalar.
* We save this as a utf8 string.
*/
val64 = in_msg->body.kvp_set.data.value_u64;
message->body.kvp_set.data.value_size =
sprintf(message->body.kvp_set.data.value,
"%llu", val64) + 1;
break;
}
case KVP_OP_GET:
message->body.kvp_set.data.key_size =
utf16s_to_utf8s(
(wchar_t *)in_msg->body.kvp_set.data.key,
in_msg->body.kvp_set.data.key_size,
UTF16_LITTLE_ENDIAN,
message->body.kvp_set.data.key,
HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
break;
case KVP_OP_DELETE:
message->body.kvp_delete.key_size =
utf16s_to_utf8s(
(wchar_t *)in_msg->body.kvp_delete.key,
in_msg->body.kvp_delete.key_size,
UTF16_LITTLE_ENDIAN,
message->body.kvp_delete.key,
HV_KVP_EXCHANGE_MAX_KEY_SIZE - 1) + 1;
break;
case KVP_OP_ENUMERATE:
message->body.kvp_enum_data.index =
in_msg->body.kvp_enum_data.index;
break;
}
msg->len = sizeof(struct hv_kvp_msg);
cn_netlink_send(msg, 0, GFP_ATOMIC);
kfree(msg);
return;
}
/*
* Send a response back to the host.
*/
static void
kvp_respond_to_host(struct hv_kvp_msg *msg_to_host, int error)
{
struct hv_kvp_msg *kvp_msg;
struct hv_kvp_exchg_msg_value *kvp_data;
char *key_name;
char *value;
struct icmsg_hdr *icmsghdrp;
int keylen = 0;
int valuelen = 0;
u32 buf_len;
struct vmbus_channel *channel;
u64 req_id;
int ret;
/*
* If a transaction is not active; log and return.
*/
if (!kvp_transaction.active) {
/*
* This is a spurious call!
*/
pr_warn("KVP: Transaction not active\n");
return;
}
/*
* Copy the global state for completing the transaction. Note that
* only one transaction can be active at a time.
*/
buf_len = kvp_transaction.recv_len;
channel = kvp_transaction.recv_channel;
req_id = kvp_transaction.recv_req_id;
kvp_transaction.active = false;
icmsghdrp = (struct icmsg_hdr *)
&recv_buffer[sizeof(struct vmbuspipe_hdr)];
if (channel->onchannel_callback == NULL)
/*
* We have raced with util driver being unloaded;
* silently return.
*/
return;
icmsghdrp->status = error;
/*
* If the error parameter is set, terminate the host's enumeration
* on this pool.
*/
if (error) {
/*
* Something failed or we have timedout;
* terminate the current host-side iteration.
*/
goto response_done;
}
kvp_msg = (struct hv_kvp_msg *)
&recv_buffer[sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
switch (kvp_transaction.kvp_msg->kvp_hdr.operation) {
case KVP_OP_GET_IP_INFO:
ret = process_ob_ipinfo(msg_to_host,
(struct hv_kvp_ip_msg *)kvp_msg,
KVP_OP_GET_IP_INFO);
if (ret < 0)
icmsghdrp->status = HV_E_FAIL;
goto response_done;
case KVP_OP_SET_IP_INFO:
goto response_done;
case KVP_OP_GET:
kvp_data = &kvp_msg->body.kvp_get.data;
goto copy_value;
case KVP_OP_SET:
case KVP_OP_DELETE:
goto response_done;
default:
break;
}
kvp_data = &kvp_msg->body.kvp_enum_data.data;
key_name = msg_to_host->body.kvp_enum_data.data.key;
/*
* The windows host expects the key/value pair to be encoded
* in utf16. Ensure that the key/value size reported to the host
* will be less than or equal to the MAX size (including the
* terminating character).
*/
keylen = utf8s_to_utf16s(key_name, strlen(key_name), UTF16_HOST_ENDIAN,
(wchar_t *) kvp_data->key,
(HV_KVP_EXCHANGE_MAX_KEY_SIZE / 2) - 2);
kvp_data->key_size = 2*(keylen + 1); /* utf16 encoding */
copy_value:
value = msg_to_host->body.kvp_enum_data.data.value;
valuelen = utf8s_to_utf16s(value, strlen(value), UTF16_HOST_ENDIAN,
(wchar_t *) kvp_data->value,
(HV_KVP_EXCHANGE_MAX_VALUE_SIZE / 2) - 2);
kvp_data->value_size = 2*(valuelen + 1); /* utf16 encoding */
/*
* If the utf8s to utf16s conversion failed; notify host
* of the error.
*/
if ((keylen < 0) || (valuelen < 0))
icmsghdrp->status = HV_E_FAIL;
kvp_data->value_type = REG_SZ; /* all our values are strings */
response_done:
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
VM_PKT_DATA_INBAND, 0);
}
/*
* This callback is invoked when we get a KVP message from the host.
* The host ensures that only one KVP transaction can be active at a time.
* KVP implementation in Linux needs to forward the key to a user-mde
* component to retrive the corresponding value. Consequently, we cannot
* respond to the host in the conext of this callback. Since the host
* guarantees that at most only one transaction can be active at a time,
* we stash away the transaction state in a set of global variables.
*/
void hv_kvp_onchannelcallback(void *context)
{
struct vmbus_channel *channel = context;
u32 recvlen;
u64 requestid;
struct hv_kvp_msg *kvp_msg;
struct icmsg_hdr *icmsghdrp;
struct icmsg_negotiate *negop = NULL;
int util_fw_version;
int kvp_srv_version;
if (kvp_transaction.active) {
/*
* We will defer processing this callback once
* the current transaction is complete.
*/
kvp_transaction.kvp_context = context;
return;
}
vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
&requestid);
if (recvlen > 0) {
icmsghdrp = (struct icmsg_hdr *)&recv_buffer[
sizeof(struct vmbuspipe_hdr)];
if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) {
/*
* Based on the host, select appropriate
* framework and service versions we will
* negotiate.
*/
switch (vmbus_proto_version) {
case (VERSION_WS2008):
util_fw_version = UTIL_WS2K8_FW_VERSION;
kvp_srv_version = WS2008_SRV_VERSION;
break;
case (VERSION_WIN7):
util_fw_version = UTIL_FW_VERSION;
kvp_srv_version = WIN7_SRV_VERSION;
break;
default:
util_fw_version = UTIL_FW_VERSION;
kvp_srv_version = WIN8_SRV_VERSION;
}
vmbus_prep_negotiate_resp(icmsghdrp, negop,
recv_buffer, util_fw_version,
kvp_srv_version);
} else {
kvp_msg = (struct hv_kvp_msg *)&recv_buffer[
sizeof(struct vmbuspipe_hdr) +
sizeof(struct icmsg_hdr)];
/*
* Stash away this global state for completing the
* transaction; note transactions are serialized.
*/
kvp_transaction.recv_len = recvlen;
kvp_transaction.recv_channel = channel;
kvp_transaction.recv_req_id = requestid;
kvp_transaction.active = true;
kvp_transaction.kvp_msg = kvp_msg;
/*
* Get the information from the
* user-mode component.
* component. This transaction will be
* completed when we get the value from
* the user-mode component.
* Set a timeout to deal with
* user-mode not responding.
*/
schedule_work(&kvp_sendkey_work);
schedule_delayed_work(&kvp_work, 5*HZ);
return;
}
icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION
| ICMSGHDRFLAG_RESPONSE;
vmbus_sendpacket(channel, recv_buffer,
recvlen, requestid,
VM_PKT_DATA_INBAND, 0);
}
}
int
hv_kvp_init(struct hv_util_service *srv)
{
int err;
err = cn_add_callback(&kvp_id, kvp_name, kvp_cn_callback);
if (err)
return err;
recv_buffer = srv->recv_buffer;
/*
* When this driver loads, the user level daemon that
* processes the host requests may not yet be running.
* Defer processing channel callbacks until the daemon
* has registered.
*/
kvp_transaction.active = true;
return 0;
}
void hv_kvp_deinit(void)
{
cn_del_callback(&kvp_id);
cancel_delayed_work_sync(&kvp_work);
cancel_work_sync(&kvp_sendkey_work);
}