// SPDX-License-Identifier: GPL-2.0-only
/*
* An implementation of host to guest copy functionality for Linux.
*
* Copyright (C) 2023, Microsoft, Inc.
*
* Author : K. Y. Srinivasan <[email protected]>
* Author : Saurabh Sengar <[email protected]>
*
*/
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <locale.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <wchar.h>
#include <sys/stat.h>
#include <linux/hyperv.h>
#include <linux/limits.h>
#include "vmbus_bufring.h"
#define ICMSGTYPE_NEGOTIATE 0
#define ICMSGTYPE_FCOPY 7
#define WIN8_SRV_MAJOR 1
#define WIN8_SRV_MINOR 1
#define WIN8_SRV_VERSION (WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
#define MAX_FOLDER_NAME 15
#define MAX_PATH_LEN 15
#define FCOPY_UIO "/sys/bus/vmbus/devices/eb765408-105f-49b6-b4aa-c123b64d17d4/uio"
#define FCOPY_VER_COUNT 1
static const int fcopy_versions[] = {
WIN8_SRV_VERSION
};
#define FW_VER_COUNT 1
static const int fw_versions[] = {
UTIL_FW_VERSION
};
#define HV_RING_SIZE 0x4000 /* 16KB ring buffer size */
unsigned char desc[HV_RING_SIZE];
static int target_fd;
static char target_fname[PATH_MAX];
static unsigned long long filesize;
static int hv_fcopy_create_file(char *file_name, char *path_name, __u32 flags)
{
int error = HV_E_FAIL;
char *q, *p;
filesize = 0;
p = path_name;
snprintf(target_fname, sizeof(target_fname), "%s/%s",
path_name, file_name);
/*
* Check to see if the path is already in place; if not,
* create if required.
*/
while ((q = strchr(p, '/')) != NULL) {
if (q == p) {
p++;
continue;
}
*q = '\0';
if (access(path_name, F_OK)) {
if (flags & CREATE_PATH) {
if (mkdir(path_name, 0755)) {
syslog(LOG_ERR, "Failed to create %s",
path_name);
goto done;
}
} else {
syslog(LOG_ERR, "Invalid path: %s", path_name);
goto done;
}
}
p = q + 1;
*q = '/';
}
if (!access(target_fname, F_OK)) {
syslog(LOG_INFO, "File: %s exists", target_fname);
if (!(flags & OVER_WRITE)) {
error = HV_ERROR_ALREADY_EXISTS;
goto done;
}
}
target_fd = open(target_fname,
O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0744);
if (target_fd == -1) {
syslog(LOG_INFO, "Open Failed: %s", strerror(errno));
goto done;
}
error = 0;
done:
if (error)
target_fname[0] = '\0';
return error;
}
/* copy the data into the file */
static int hv_copy_data(struct hv_do_fcopy *cpmsg)
{
ssize_t len;
int ret = 0;
len = pwrite(target_fd, cpmsg->data, cpmsg->size, cpmsg->offset);
filesize += cpmsg->size;
if (len != cpmsg->size) {
switch (errno) {
case ENOSPC:
ret = HV_ERROR_DISK_FULL;
break;
default:
ret = HV_E_FAIL;
break;
}
syslog(LOG_ERR, "pwrite failed to write %llu bytes: %ld (%s)",
filesize, (long)len, strerror(errno));
}
return ret;
}
static int hv_copy_finished(void)
{
close(target_fd);
target_fname[0] = '\0';
return 0;
}
static void print_usage(char *argv[])
{
fprintf(stderr, "Usage: %s [options]\n"
"Options are:\n"
" -n, --no-daemon stay in foreground, don't daemonize\n"
" -h, --help print this help\n", argv[0]);
}
static bool vmbus_prep_negotiate_resp(struct icmsg_hdr *icmsghdrp, unsigned char *buf,
unsigned int buflen, const int *fw_version, int fw_vercnt,
const int *srv_version, int srv_vercnt,
int *nego_fw_version, int *nego_srv_version)
{
int icframe_major, icframe_minor;
int icmsg_major, icmsg_minor;
int fw_major, fw_minor;
int srv_major, srv_minor;
int i, j;
bool found_match = false;
struct icmsg_negotiate *negop;
/* Check that there's enough space for icframe_vercnt, icmsg_vercnt */
if (buflen < ICMSG_HDR + offsetof(struct icmsg_negotiate, reserved)) {
syslog(LOG_ERR, "Invalid icmsg negotiate");
return false;
}
icmsghdrp->icmsgsize = 0x10;
negop = (struct icmsg_negotiate *)&buf[ICMSG_HDR];
icframe_major = negop->icframe_vercnt;
icframe_minor = 0;
icmsg_major = negop->icmsg_vercnt;
icmsg_minor = 0;
/* Validate negop packet */
if (icframe_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT ||
icmsg_major > IC_VERSION_NEGOTIATION_MAX_VER_COUNT ||
ICMSG_NEGOTIATE_PKT_SIZE(icframe_major, icmsg_major) > buflen) {
syslog(LOG_ERR, "Invalid icmsg negotiate - icframe_major: %u, icmsg_major: %u\n",
icframe_major, icmsg_major);
goto fw_error;
}
/*
* Select the framework version number we will
* support.
*/
for (i = 0; i < fw_vercnt; i++) {
fw_major = (fw_version[i] >> 16);
fw_minor = (fw_version[i] & 0xFFFF);
for (j = 0; j < negop->icframe_vercnt; j++) {
if (negop->icversion_data[j].major == fw_major &&
negop->icversion_data[j].minor == fw_minor) {
icframe_major = negop->icversion_data[j].major;
icframe_minor = negop->icversion_data[j].minor;
found_match = true;
break;
}
}
if (found_match)
break;
}
if (!found_match)
goto fw_error;
found_match = false;
for (i = 0; i < srv_vercnt; i++) {
srv_major = (srv_version[i] >> 16);
srv_minor = (srv_version[i] & 0xFFFF);
for (j = negop->icframe_vercnt;
(j < negop->icframe_vercnt + negop->icmsg_vercnt);
j++) {
if (negop->icversion_data[j].major == srv_major &&
negop->icversion_data[j].minor == srv_minor) {
icmsg_major = negop->icversion_data[j].major;
icmsg_minor = negop->icversion_data[j].minor;
found_match = true;
break;
}
}
if (found_match)
break;
}
/*
* Respond with the framework and service
* version numbers we can support.
*/
fw_error:
if (!found_match) {
negop->icframe_vercnt = 0;
negop->icmsg_vercnt = 0;
} else {
negop->icframe_vercnt = 1;
negop->icmsg_vercnt = 1;
}
if (nego_fw_version)
*nego_fw_version = (icframe_major << 16) | icframe_minor;
if (nego_srv_version)
*nego_srv_version = (icmsg_major << 16) | icmsg_minor;
negop->icversion_data[0].major = icframe_major;
negop->icversion_data[0].minor = icframe_minor;
negop->icversion_data[1].major = icmsg_major;
negop->icversion_data[1].minor = icmsg_minor;
return found_match;
}
static void wcstoutf8(char *dest, const __u16 *src, size_t dest_size)
{
size_t len = 0;
while (len < dest_size) {
if (src[len] < 0x80)
dest[len++] = (char)(*src++);
else
dest[len++] = 'X';
}
dest[len] = '\0';
}
static int hv_fcopy_start(struct hv_start_fcopy *smsg_in)
{
setlocale(LC_ALL, "en_US.utf8");
size_t file_size, path_size;
char *file_name, *path_name;
char *in_file_name = (char *)smsg_in->file_name;
char *in_path_name = (char *)smsg_in->path_name;
file_size = wcstombs(NULL, (const wchar_t *restrict)in_file_name, 0) + 1;
path_size = wcstombs(NULL, (const wchar_t *restrict)in_path_name, 0) + 1;
file_name = (char *)malloc(file_size * sizeof(char));
path_name = (char *)malloc(path_size * sizeof(char));
wcstoutf8(file_name, (__u16 *)in_file_name, file_size);
wcstoutf8(path_name, (__u16 *)in_path_name, path_size);
return hv_fcopy_create_file(file_name, path_name, smsg_in->copy_flags);
}
static int hv_fcopy_send_data(struct hv_fcopy_hdr *fcopy_msg, int recvlen)
{
int operation = fcopy_msg->operation;
/*
* The strings sent from the host are encoded 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 W_MAX_PATH -1 to guarantee
* that the strings can be properly terminated!
*/
switch (operation) {
case START_FILE_COPY:
return hv_fcopy_start((struct hv_start_fcopy *)fcopy_msg);
case WRITE_TO_FILE:
return hv_copy_data((struct hv_do_fcopy *)fcopy_msg);
case COMPLETE_FCOPY:
return hv_copy_finished();
}
return HV_E_FAIL;
}
/* process the packet recv from host */
static int fcopy_pkt_process(struct vmbus_br *txbr)
{
int ret, offset, pktlen;
int fcopy_srv_version;
const struct vmbus_chanpkt_hdr *pkt;
struct hv_fcopy_hdr *fcopy_msg;
struct icmsg_hdr *icmsghdr;
pkt = (const struct vmbus_chanpkt_hdr *)desc;
offset = pkt->hlen << 3;
pktlen = (pkt->tlen << 3) - offset;
icmsghdr = (struct icmsg_hdr *)&desc[offset + sizeof(struct vmbuspipe_hdr)];
icmsghdr->status = HV_E_FAIL;
if (icmsghdr->icmsgtype == ICMSGTYPE_NEGOTIATE) {
if (vmbus_prep_negotiate_resp(icmsghdr, desc + offset, pktlen, fw_versions,
FW_VER_COUNT, fcopy_versions, FCOPY_VER_COUNT,
NULL, &fcopy_srv_version)) {
syslog(LOG_INFO, "FCopy IC version %d.%d",
fcopy_srv_version >> 16, fcopy_srv_version & 0xFFFF);
icmsghdr->status = 0;
}
} else if (icmsghdr->icmsgtype == ICMSGTYPE_FCOPY) {
/* Ensure recvlen is big enough to contain hv_fcopy_hdr */
if (pktlen < ICMSG_HDR + sizeof(struct hv_fcopy_hdr)) {
syslog(LOG_ERR, "Invalid Fcopy hdr. Packet length too small: %u",
pktlen);
return -ENOBUFS;
}
fcopy_msg = (struct hv_fcopy_hdr *)&desc[offset + ICMSG_HDR];
icmsghdr->status = hv_fcopy_send_data(fcopy_msg, pktlen);
}
icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
ret = rte_vmbus_chan_send(txbr, 0x6, desc + offset, pktlen, 0);
if (ret) {
syslog(LOG_ERR, "Write to ringbuffer failed err: %d", ret);
return ret;
}
return 0;
}
static void fcopy_get_first_folder(char *path, char *chan_no)
{
DIR *dir = opendir(path);
struct dirent *entry;
if (!dir) {
syslog(LOG_ERR, "Failed to open directory (errno=%s).\n", strerror(errno));
return;
}
while ((entry = readdir(dir)) != NULL) {
if (entry->d_type == DT_DIR && strcmp(entry->d_name, ".") != 0 &&
strcmp(entry->d_name, "..") != 0) {
strcpy(chan_no, entry->d_name);
break;
}
}
closedir(dir);
}
int main(int argc, char *argv[])
{
int fcopy_fd = -1, tmp = 1;
int daemonize = 1, long_index = 0, opt, ret = -EINVAL;
struct vmbus_br txbr, rxbr;
void *ring;
uint32_t len = HV_RING_SIZE;
char uio_name[MAX_FOLDER_NAME] = {0};
char uio_dev_path[MAX_PATH_LEN] = {0};
static struct option long_options[] = {
{"help", no_argument, 0, 'h' },
{"no-daemon", no_argument, 0, 'n' },
{0, 0, 0, 0 }
};
while ((opt = getopt_long(argc, argv, "hn", long_options,
&long_index)) != -1) {
switch (opt) {
case 'n':
daemonize = 0;
break;
case 'h':
default:
print_usage(argv);
goto exit;
}
}
if (daemonize && daemon(1, 0)) {
syslog(LOG_ERR, "daemon() failed; error: %s", strerror(errno));
goto exit;
}
openlog("HV_UIO_FCOPY", 0, LOG_USER);
syslog(LOG_INFO, "starting; pid is:%d", getpid());
fcopy_get_first_folder(FCOPY_UIO, uio_name);
snprintf(uio_dev_path, sizeof(uio_dev_path), "/dev/%s", uio_name);
fcopy_fd = open(uio_dev_path, O_RDWR);
if (fcopy_fd < 0) {
syslog(LOG_ERR, "open %s failed; error: %d %s",
uio_dev_path, errno, strerror(errno));
ret = fcopy_fd;
goto exit;
}
ring = vmbus_uio_map(&fcopy_fd, HV_RING_SIZE);
if (!ring) {
ret = errno;
syslog(LOG_ERR, "mmap ringbuffer failed; error: %d %s", ret, strerror(ret));
goto close;
}
vmbus_br_setup(&txbr, ring, HV_RING_SIZE);
vmbus_br_setup(&rxbr, (char *)ring + HV_RING_SIZE, HV_RING_SIZE);
rxbr.vbr->imask = 0;
while (1) {
/*
* In this loop we process fcopy messages after the
* handshake is complete.
*/
ret = pread(fcopy_fd, &tmp, sizeof(int), 0);
if (ret < 0) {
syslog(LOG_ERR, "pread failed: %s", strerror(errno));
continue;
}
len = HV_RING_SIZE;
ret = rte_vmbus_chan_recv_raw(&rxbr, desc, &len);
if (unlikely(ret <= 0)) {
/* This indicates a failure to communicate (or worse) */
syslog(LOG_ERR, "VMBus channel recv error: %d", ret);
} else {
ret = fcopy_pkt_process(&txbr);
if (ret < 0)
goto close;
/* Signal host */
if ((write(fcopy_fd, &tmp, sizeof(int))) != sizeof(int)) {
ret = errno;
syslog(LOG_ERR, "Signal to host failed: %s\n", strerror(ret));
goto close;
}
}
}
close:
close(fcopy_fd);
exit:
return ret;
}
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