san/tools/kasan_install

   1 #!/bin/bash
   2
   3 #
   4 # kasan_install: set up a system to run the KASan kernel. Run with "--uninstall"
   5 # to reverse the setup.
   6 #
   7 # Adds kcsuffix=kasan to boot-args.
   8 #
   9
  10
  11 if [[ `whoami` != root ]] ; then
  12         echo "Re-running with sudo"
  13         sudo "$0" "$@"
  14         exit $?
  15 fi
  16
  17 sip_enabled() {
  18         csrutil status |grep -q enabled
  19 }
  20
  21 prompt() {
  22         echo -n "$@ [y/N] "
  23         read ans
  24         case "$ans" in
  25                 [yY]*) return 0 ;;
  26                 *) return 1 ;;
  27         esac
  28 }
  29
  30 kasan_install() {
  31
  32         dobootargs=0
  33
  34         echo -n "Checking KASan boot args... "
  35
  36         bootargs=$(nvram boot-args | cut -f2)
  37         cursuffix=$(echo $bootargs | sed -n 's/.*kcsuffix=\([^ ]\)/\1/p')
  38
  39         if [[ "$cursuffix" == kasan ]] ; then
  40                 echo "already set."
  41         elif [[ -n "$cursuffix" ]] ; then
  42                 prompt "custom kcsuffix ($cursuffix) is set. Overwrite?" && {
  43                         bootargs=$(echo "$bootargs" | sed 's/[ ]*kcsuffix=[^ ]*//')
  44                         dobootargs=1
  45                 }
  46         else
  47                 prompt "not set. Modify?" && {
  48                         dobootargs=1
  49                 }
  50         fi
  51
  52         [[ $dobootargs -eq 1 ]] && {
  53                 echo -n "Adding boot arg kcsuffix=kasan... "
  54                 newlen=$(echo -n "$bootargs kcsuffix=kasan" |wc -c)
  55                 if [[ $newlen -ge 512 ]] ; then
  56                         echo "boot-args too long. Bailing."
  57                         exit 3
  58                 fi
  59
  60                 nvram boot-args="$bootargs kcsuffix=kasan" || exit $?
  61                 echo "done."
  62         }
  63
  64 }
  65
  66
  67 kasan_uninstall() {
  68
  69         echo -n "Removing boot args... "
  70
  71         bootargs=$(nvram boot-args | cut -f2)
  72         cursuffix=$(echo $bootargs | sed -n 's/.*kcsuffix=\([^ ]\)/\1/p')
  73
  74         if [[ $cursuffix == "kasan" ]] ; then
  75                 prompt "remove kcsuffix=kasan?" && {
  76                         echo -n "Removing kcsuffix... "
  77                         bootargs=$(echo "$bootargs" | sed 's/[ ]*kcsuffix=[^ ]*//')
  78                         nvram boot-args="$bootargs"
  79                         echo "done."
  80                 }
  81         else
  82                 echo "not set."
  83         fi
  84
  85 }
  86
  87 case "$1" in
  88         *uninstall|*del*|*remove|*rm)
  89                 kasan_uninstall ;;
  90         *)
  91                 kasan_install ;;
  92 esac