cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

common.nbd (2884B)


      1#!/usr/bin/env bash
      2# -*- shell-script-mode -*-
      3#
      4# Helpers for NBD server related config
      5#
      6# Copyright (C) 2018 Red Hat, Inc.
      7#
      8# This program is free software; you can redistribute it and/or modify
      9# it under the terms of the GNU General Public License as published by
     10# the Free Software Foundation; either version 2 of the License, or
     11# (at your option) any later version.
     12#
     13# This program is distributed in the hope that it will be useful,
     14# but WITHOUT ANY WARRANTY; without even the implied warranty of
     15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     16# GNU General Public License for more details.
     17#
     18# You should have received a copy of the GNU General Public License
     19# along with this program.  If not, see <http://www.gnu.org/licenses/>.
     20#
     21
     22nbd_unix_socket="${SOCK_DIR}/qemu-nbd.sock"
     23nbd_tcp_addr="127.0.0.1"
     24nbd_pid_file="${TEST_DIR}/qemu-nbd.pid"
     25nbd_stderr_fifo="${TEST_DIR}/qemu-nbd.fifo"
     26
     27# If bash version is >= 4.1, this will be overwritten by a dynamically
     28# assigned file descriptor value.
     29nbd_fifo_fd=10
     30
     31nbd_server_stop()
     32{
     33    local NBD_PID
     34    if [ -f "$nbd_pid_file" ]; then
     35        read NBD_PID < "$nbd_pid_file"
     36        rm -f "$nbd_pid_file"
     37        if [ -n "$NBD_PID" ]; then
     38            kill "$NBD_PID"
     39        fi
     40    fi
     41    rm -f "$nbd_unix_socket" "$nbd_stderr_fifo"
     42}
     43
     44nbd_server_start_unix_socket()
     45{
     46    nbd_server_stop
     47    $QEMU_NBD -v -t -k "$nbd_unix_socket" --fork "$@"
     48}
     49
     50nbd_server_start_tcp_socket()
     51{
     52    nbd_server_stop
     53
     54    mkfifo "$nbd_stderr_fifo"
     55    for ((port = 10809; port <= 10909; port++))
     56    do
     57        # Redirect stderr to FIFO, so we can later decide whether we
     58        # want to read it or to redirect it to our stderr, depending
     59        # on whether the command fails or not
     60        $QEMU_NBD -v -t -b $nbd_tcp_addr -p $port --fork "$@" \
     61            2> "$nbd_stderr_fifo" &
     62
     63        # Taken from common.qemu
     64        if [[ "${BASH_VERSINFO[0]}" -ge "5" ||
     65            ("${BASH_VERSINFO[0]}" -ge "4" && "${BASH_VERSINFO[1]}" -ge "1") ]]
     66        then
     67            exec {nbd_fifo_fd}<"$nbd_stderr_fifo"
     68        else
     69            let _nbd_fifo_fd++
     70            eval "exec ${_nbd_fifo_fd}<'$nbd_stderr_fifo'"
     71        fi
     72        wait $!
     73
     74        if test $? == 0
     75        then
     76            # Success, redirect qemu-nbd's stderr to our stderr
     77            nbd_tcp_port=$port
     78            (cat <&$nbd_fifo_fd >&2) &
     79            eval "exec $nbd_fifo_fd>&-"
     80            return
     81        fi
     82
     83        # Failure, read the output
     84        output=$(cat <&$nbd_fifo_fd)
     85        eval "exec $nbd_fifo_fd>&-"
     86
     87        if ! echo "$output" | grep -q "Address already in use"
     88        then
     89            # Unknown error, print it
     90            echo "$output" >&2
     91            rm -f "$nbd_stderr_fifo"
     92            exit 1
     93        fi
     94    done
     95
     96    echo "Cannot find free TCP port for nbd in range 10809-10909"
     97    rm -f "$nbd_stderr_fifo"
     98    exit 1
     99}