conf_files/pl_boot

   1 #!/bin/sh
   2
   3 # Run gpg once to create default options
   4 GNUPGHOME=/root
   5 export GNUPGHOME
   6 /usr/bin/gpg --yes 2>/dev/null </dev/null
   7
   8 # if this file is present, cancel the boot (exit this script)
   9 CANCEL_BOOT_FLAG=/tmp/CANCEL_BOOT
  10
  11 # how many times to fail in attempting to contact primary server
  12 # before falling back to original. if the backup fails this many times
  13 # too, then the process is repeated started with the primary server
  14 ATTEMPTS_BEFORE_BACKUP=3
  15
  16 # where all the configuration files for contacting
  17 # the boot server are stored
  18 BOOT_DIR=/usr/boot/
  19
  20 # get the server we are going to be contacting
  21 BOOT_SERVER=`cat $BOOT_DIR/boot_server`
  22 BOOT_SERVER_PORT=`cat $BOOT_DIR/boot_server_port`
  23
  24 # the file to request from the boot server
  25 BOOT_SERVER_PATH=`cat $BOOT_DIR/boot_server_path`
  26
  27 # location of the cacert for this boot server
  28 BOOT_SERVER_CACERT=$BOOT_DIR/cacert.pem
  29
  30 # location of the gpg key ring to verify scripts
  31 BOOT_SERVER_GPG_KEYRING=$BOOT_DIR/pubring.gpg
  32
  33 # get the backup server we are going to be contacting
  34 BACKUP_BOOT_SERVER=`cat $BOOT_DIR/backup/boot_server`
  35 BACKUP_BOOT_SERVER_PORT=`cat $BOOT_DIR/backup/boot_server_port`
  36
  37 # the file to request from the backup boot server
  38 BACKUP_BOOT_SERVER_PATH=`cat $BOOT_DIR/backup/boot_server_path`
  39
  40 # location of the cacert for the backup boot server
  41 BACKUP_BOOT_SERVER_CACERT=$BOOT_DIR/backup/cacert.pem
  42
  43 # location of the gpg key ring for backup server to verify scripts
  44 BACKUP_BOOT_SERVER_GPG_KEYRING=$BOOT_DIR/backup/pubring.gpg
  45
  46 # location of a file containing this boot cd version
  47 BOOT_VERSION_FILE=/pl_version
  48
  49 # the locations of the downloaded scripts
  50 UNVERIFIED_SCRIPT=/tmp/bootscript.gpg
  51 VERIFIED_SCRIPT=/tmp/bootscript
  52
  53
  54 # --------------------------
  55
  56
  57 # now, contact the boot server, run the script, and do it over again.
  58 contact_count=0
  59
  60 # set to one when we are trying to contact backup server
  61 on_backup_server=0
  62
  63 # start out contacting the primary servers
  64 CONNECT_BOOT_SERVER=$BOOT_SERVER
  65 CONNECT_BOOT_SERVER_PORT=$BOOT_SERVER_PORT
  66 CONNECT_BOOT_SERVER_PATH=$BOOT_SERVER_PATH
  67 CONNECT_BOOT_SERVER_GPG_KEYRING=$BOOT_SERVER_GPG_KEYRING
  68 CONNECT_BOOT_SERVER_CACERT=$BOOT_SERVER_CACERT
  69
  70 while : ; do
  71
  72     if [[ -f $CANCEL_BOOT_FLAG ]]; then
  73         echo "pl_boot: got request to cancel boot, exiting"
  74         exit 0
  75     fi
  76
  77     if [[ $contact_count -ge $ATTEMPTS_BEFORE_BACKUP ]]; then
  78
  79         contact_count=0
  80
  81         if [[ $on_backup_server == 1 ]]; then
  82             echo "pl_boot: failed to contact backup server, trying primary."
  83
  84             on_backup_server=0
  85
  86             CONNECT_BOOT_SERVER=$BOOT_SERVER
  87             CONNECT_BOOT_SERVER_PORT=$BOOT_SERVER_PORT
  88             CONNECT_BOOT_SERVER_PATH=$BOOT_SERVER_PATH
  89             CONNECT_BOOT_SERVER_GPG_KEYRING=$BOOT_SERVER_GPG_KEYRING
  90             CONNECT_BOOT_SERVER_CACERT=$BOOT_SERVER_CACERT
  91         else
  92             echo "pl_boot: failed to contact primary server, trying backup."
  93
  94             on_backup_server=1
  95
  96             CONNECT_BOOT_SERVER=$BACKUP_BOOT_SERVER
  97             CONNECT_BOOT_SERVER_PORT=$BACKUP_BOOT_SERVER_PORT
  98             CONNECT_BOOT_SERVER_PATH=$BACKUP_BOOT_SERVER_PATH
  99             CONNECT_BOOT_SERVER_GPG_KEYRING=$BACKUP_BOOT_SERVER_GPG_KEYRING
 100             CONNECT_BOOT_SERVER_CACERT=$BACKUP_BOOT_SERVER_CACERT
 101         fi
 102     fi
 103
 104     if [[ $contact_count != 0 ]]; then
 105
 106         if [[ $on_backup_server == 1 ]]; then
 107             echo "pl_boot: attempting to fetch script from backup server in 30s"
 108         else
 109             echo "pl_boot: attempting to fetch script from primary server in 30s"
 110         fi
 111         /bin/sleep 30
 112     fi
 113
 114     # assemble the curl transaction
 115     CURL_CMD="/usr/bin/curl \
 116         --connect-timeout 60 \
 117         --max-time 600 \
 118         --form version=<$BOOT_VERSION_FILE \
 119         --form cmdline=</proc/cmdline \
 120         --form uptime=</proc/uptime \
 121         --form ifconfig=</tmp/ifconfig \
 122         --form nonce=</tmp/nonce \
 123         --location \
 124         --output $UNVERIFIED_SCRIPT \
 125         --sslv3  \
 126         --silent \
 127         --show-error \
 128         --fail \
 129         --stderr /tmp/curl_errors \
 130         --cacert $CONNECT_BOOT_SERVER_CACERT \
 131    https://$CONNECT_BOOT_SERVER:$CONNECT_BOOT_SERVER_PORT/$CONNECT_BOOT_SERVER_PATH"
 132
 133     # assemble the gpg command line
 134     GPG_CMD="/usr/bin/gpg \
 135         --no-default-keyring \
 136         --keyring $CONNECT_BOOT_SERVER_GPG_KEYRING \
 137         --output $VERIFIED_SCRIPT \
 138         --always-trust \
 139         --decrypt $UNVERIFIED_SCRIPT"
 140
 141     echo "pl_boot: generating new nonce"
 142     /usr/bin/head --bytes=32 /dev/urandom | \
 143         /usr/bin/od -tx1 -An --width=32 | \
 144         /bin/sed 's/ //g' > /tmp/nonce
 145
 146     echo "pl_boot: fetching script from boot server $CONNECT_BOOT_SERVER"
 147     ((contact_count++))
 148     rm -f $UNVERIFIED_SCRIPT
 149     $CURL_CMD
 150     curl_err=$?
 151     if [ $curl_err -ne 0 ]; then
 152         echo "pl_boot: curl request failed with error $curl_err:"
 153         cat /tmp/curl_errors
 154         echo
 155         continue
 156     fi
 157
 158     echo "pl_boot: verifying downloaded script"
 159     rm -f $VERIFIED_SCRIPT
 160     $GPG_CMD 2> /tmp/gpg_errors
 161     if [ $? -ne 0 ]; then
 162         echo "pl_boot: failed to verify file:"
 163         cat /tmp/gpg_errors
 164         echo
 165         continue
 166     fi
 167     echo "pl_boot: decrypted and verified script succesfully"
 168
 169     echo "pl_boot: handing control to download script"
 170     rm -f $UNVERIFIED_SCRIPT
 171     chmod +x $VERIFIED_SCRIPT
 172     $VERIFIED_SCRIPT
 173
 174     echo "pl_boot: downloaded script has returned"
 175 done
 176
 177 echo "pl_boot: automatic boot process canceled by user"