From 4aeeefd261ad372448dfb9584da31f596b2538b4 Mon Sep 17 00:00:00 2001
From: Jeffrey Townsend <jeffrey.townsend@bigswitch.com>
Date: Fri, 11 Dec 2015 21:34:35 +0000
Subject: [PATCH] Installer SHAR support.

---
 tools/mkshar            | 240 ++++++++++++++++++++++++++++++++++
 tools/scripts/sfx.sh.in | 283 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 523 insertions(+)
 create mode 100755 tools/mkshar
 create mode 100644 tools/scripts/sfx.sh.in

diff --git a/tools/mkshar b/tools/mkshar
new file mode 100755
index 00000000..138f2755
--- /dev/null
+++ b/tools/mkshar
@@ -0,0 +1,240 @@
+#!/usr/bin/python
+
+"""mkshar
+
+Generate a shar (with a zip file payload) for a Switch Light installer.
+"""
+
+import sys, os, shutil
+import subprocess
+import hashlib
+import optparse
+
+HELP = """\
+%prog [OPTIONS] SHAR-OUTPUT SFX-FRAGMENT INSTALL-SCRIPT [ARG ...]
+"""
+
+parser = optparse.OptionParser(usage=HELP)
+parser.add_option('--blocksize',
+                  type=int, default=512,
+                  help="Set block size for e.g. 'dd'")
+parser.add_option('--bzip',
+                  action='store_true',
+                  help="Enable bzip2")
+parser.add_option('--lazy',
+                  action='store_true',
+                  help="Enable lazy unpacking")
+parser.add_option('--unzip-sfx',
+                  action='store_true',
+                  help="Use 'unzip' to natively handle SFX preamble")
+parser.add_option('--unzip-pipe',
+                  action='store_true',
+                  help="Enable 'dd' to handle SFX preamble")
+parser.add_option('--unzip-loop',
+                  action='store_true',
+                  help="Enable 'losetup' to handle SFX preamble")
+parser.add_option('--unzip-pad',
+                  action='store_true',
+                  help="Special pad options for deficient unzip")
+parser.add_option('--fixup-perms',
+                  type=str,
+                  help="Post-unpack shell script to fix permissions")
+
+opts, args = parser.parse_args()
+
+ZIP = "/usr/bin/zip"
+ZIP_OPTS = ['-v',
+            '-y',
+            '-n', '.zip:.loader:.swi:.jar:.gz:.bz:.bz2:.xz',]
+
+# enable (experimental) bzip2, make sure that
+# busybox unzip supports it
+# Ha ha, using '-9' not only cranks up the compression,
+# but *ignores* the suffix list for 'store-only'.
+if opts.bzip:
+    ZIP_COMPRESS_OPTS = ['-Z', 'bzip2', '-8',]
+else:
+    ZIP_COMPRESS_OPTS = ['-8',]
+
+shar = args.pop(0)
+sfx = args.pop(0)
+install = args.pop(0)
+
+import logging
+logging.basicConfig()
+logger = logging.getLogger("mkshar")
+logger.setLevel(logging.DEBUG)
+
+logger.info("initializing ZIP")
+zipFile = os.path.abspath(shar + ".zip.in")
+if os.path.exists(zipFile):
+    logger.debug("+ /bin/rm %s", zipFile)
+    os.unlink(zipFile)
+
+def _addfile(path, *opts):
+    logger.info("adding file %s with opts %s",
+                path, " ".join(opts))
+    cmd = [ZIP,] + ZIP_OPTS + list(opts) + ['-u', zipFile, path,]
+    subprocess.check_call(cmd)
+
+def _addfiles(paths, *opts):
+    logger.info("adding %d files with opts %s",
+                len(paths), " ".join(opts))
+    cmd = [ZIP,] + ZIP_OPTS + list(opts) + [zipFile,] + paths
+    subprocess.check_call(cmd)
+
+def _zipopts(path):
+    ext = os.path.splitext(path)[1].lower()
+    if ext in ('.loader', '.zip', '.swi',):
+        return ['-0',]
+    else:
+        return ZIP_COMPRESS_OPTS
+
+# block to 512 bytes
+buf = open(sfx).read()
+sz = len(buf)
+logger.info("script size is %d bytes", sz)
+rem = sz % opts.blocksize
+pad = opts.blocksize - rem
+
+# extra block for house keeping
+if opts.unzip_pad:
+    pad = pad + opts.blocksize
+
+if pad == 1:
+    buf += "\n"
+elif pad > 1:
+    pad -= 1
+    buf = buf + ('#' * pad) + "\n"
+
+logger.info("padded script size is %d bytes", len(buf))
+
+if opts.unzip_pad:
+    logger.info("adding SFX pad to beginning as archive item")
+    fd = open("pad.bin", "w")
+    fd.write(('#' * (len(buf)-1)))
+    fd.write('\n')
+    fd.close()
+    _addfile("pad.bin", '-0', '-j')
+    os.unlink("pad.bin")
+
+_addfile(install, '-0')
+
+if opts.fixup_perms:
+    _addfile(opts.fixup_perms, '-0')
+
+logger.info("adding other payload items")
+o = ['-r',] + ZIP_COMPRESS_OPTS
+_addfiles(args, *o)
+
+def _splice(tag, val):
+    global buf
+    pat = tag + '='
+    p = buf.find(pat)
+    q = buf.find("\n", p+1)
+    if p < 0:
+        raise ValueError("cannot find tag %s" % repr(tag))
+    llen = q - p
+    line = "%s=%s #" % (tag, str(val),)
+    if len(line) > llen:
+        raise SystemExit("cannot insert byte count marker")
+    llen -= len(line)
+    line = line + ('#' * llen)
+    buf = buf[:p] + line + buf[q:]
+
+logger.info("prepping SFX")
+
+_splice('SFX_BYTES', len(buf))
+_splice('SFX_BLOCKSIZE', opts.blocksize)
+_splice('SFX_INSTALL', os.path.split(install)[1])
+_splice('SFX_CHECKSUM', '')
+if opts.lazy:
+    _splice('SFX_LAZY', '1')
+else:
+    _splice('SFX_LAZY', '')
+if opts.unzip_sfx:
+    _splice('SFX_UNZIP', '1')
+else:
+    _splice('SFX_UNZIP', '')
+if opts.unzip_pipe:
+    _splice('SFX_PIPE', '1')
+else:
+    _splice('SFX_PIPE', '')
+if opts.unzip_loop:
+    _splice('SFX_LOOP', '1')
+else:
+    _splice('SFX_LOOP', '')
+if opts.unzip_pad:
+    _splice('SFX_PAD', 'pad.bin')
+else:
+    _splice('SFX_PAD', '')
+if opts.fixup_perms:
+    _splice('SFX_PERMS', opts.fixup_perms)
+
+# remember the checksum offset
+ckStart = buf.find("SFX_CHECKSUM=")
+ckEnd = buf.find("\n", ckStart+1)
+
+logger.info("generating shar")
+
+if opts.unzip_pad:
+
+    wfd = open(shar, "w+")
+    rfd = open(zipFile, "r")
+    shutil.copyfileobj(rfd, wfd)
+    rfd.close()
+
+    logger.info("capturing first block")
+    wfd.seek(0, 0)
+    magic = wfd.read(opts.blocksize)
+
+    logger.info("splicing in SFX")
+    wfd.seek(0, 0)
+    wfd.write(buf)
+
+    logger.info("saving first block")
+    wfd.seek(len(buf)-opts.blocksize, 0)
+    wfd.write(magic)
+
+    wfd.close()
+
+    # adjust buf to include magic
+    buf = buf[:-opts.blocksize] + magic
+
+else:
+
+    wfd = open(shar, "w")
+    wfd.write(buf)
+    rfd = open(zipFile, "r")
+    shutil.copyfileobj(rfd, wfd)
+    rfd.close()
+    wfd.close()
+
+    logger.info("adjusting SFX")
+    cmd = [ZIP,] + ZIP_OPTS + ['-A', shar,]
+    subprocess.check_call(cmd)
+
+# compute the actual checksum
+ckf = hashlib.md5()
+ckf.update(buf[:ckStart])
+ckf.update(buf[ckEnd+1:])
+
+rfd = open(shar, "r")
+rfd.seek(len(buf), 0)
+while True:
+    buf = rfd.read(10*1024)
+    if not buf: break
+    ckf.update(buf)
+rfd.close()
+
+logger.info("adjusting checksum")
+wfd = open(shar, "r+")
+wfd.seek(ckStart, 0)
+wfd.write("SFX_CHECKSUM=%s #" % ckf.hexdigest())
+wfd.close()
+
+logger.info("+ /bin/chmod +x %s", shar)
+os.chmod(shar, 0755)
+
+logger.debug("+ /bin/rm %s", zipFile)
+os.unlink(zipFile)
diff --git a/tools/scripts/sfx.sh.in b/tools/scripts/sfx.sh.in
new file mode 100644
index 00000000..bd1598bc
--- /dev/null
+++ b/tools/scripts/sfx.sh.in
@@ -0,0 +1,283 @@
+#!/bin/sh
+
+set -e
+
+CMD=${0##*/}
+
+UNZIP=/usr/bin/unzip
+
+UNZIPOPTS=
+UNZIPARGS=
+UNZIPDIR=
+UNZIPQ="-q"
+UNZIPV=
+
+UNZIPLOOP=
+
+mode=install
+
+SHAR=$0
+
+shardir=`dirname $SHAR`
+shardir=`cd $shardir && pwd`
+SHARABS="$shardir"/${SHAR##*/}
+
+SFX_BYTES=0 ## fill in the size (padded) of this SFX header ##################
+SFX_BLOCKSIZE=1 ## use a larger block size, 'dd bs=1' is sometimes slow ######
+SFX_CHECKSUM= ## compute checksum over this SFX and the payload ##############
+SFX_INSTALL=install ## internal script in the payload to run #################
+SFX_PERMS= ## internal script to correct file permissions ####################
+SFX_PAD= ## pad file (this payload) to skip during unpack ####################
+SFX_LAZY=  ## set to '1' to defer extraction to SFX_INSTALL ##################
+SFX_UNZIP=1  ## set to '' if this unzip cannot parse SFX headers #############
+SFX_LOOP=1   ## set to '' if this unzip cannot read from a loopback/block ####
+SFX_PIPE=1   ## set to '' if this unzip cannot read from a pipe ##############
+
+if test "$SFX_PAD"; then
+  UNZIPARGS=$UNZIPARGS${UNZIPARGS:+" "}"-x $SFX_PAD"
+fi
+
+while test $# -gt 0; do
+  case "$1" in
+    -x)
+      # N.B. that busybox unzip has trouble with multiple files
+      mode=unzip
+      shift
+      UNZIPARGS=$UNZIPARGS${UNZIPARGS:+" "}"$1"
+      shift
+      UNZIPARGS=$UNZIPARGS${UNZIPARGS:+" "}"$1"
+      continue
+      ;;
+    -d)
+      shift
+      UNZIPDIR=$1
+      shift
+      continue
+      ;;
+    -v)
+      UNZIPQ=
+      UNZIPV="$1"
+      shift
+      ;;
+    -q)
+      UNZIPQ="$1"
+      UNZIPV=
+      shift
+      ;;
+    -*)
+      mode=unzip
+      UNZIPOPTS=$UNZIPOPTS${UNZIPOPTS:+" "}"$1"
+      shift
+      ;;
+    *)
+      mode=unzip
+      UNZIPARGS=$UNZIPARGS${UNZIPARGS:+" "}"$1"
+      shift
+      continue
+      ;;
+  esac
+done
+
+if test "$SFX_BLOCKSIZE" -gt 1; then
+  SFX_BLOCKS=$(($SFX_BYTES / $SFX_BLOCKSIZE))
+  SFX_TRAILER=$(($SFX_BYTES % $SFX_BLOCKSIZE))
+  if test $SFX_TRAILER -ne 0; then
+    echo "$CMD: *** SFX is not block-aligned" 1>&2
+    exit 1
+  fi
+else
+  echo "$CMD: *** SFX is blocked, dd may be slow" 1>&2
+fi
+
+workdir=`mktemp -t -d sfx-XXXXXX` || exit 1
+do_cleanup()
+{
+  if test -b "$UNZIPLOOP"; then
+    losetup -d "$UNZIPLOOP" || :
+  fi
+  cd /
+  /bin/rm -fr $workdir 2>/dev/null
+}
+trap "do_cleanup" 0 1
+
+_t()
+{
+  local c z
+  c="$1"; shift
+  z="$1"; shift
+  $c | $UNZIP $UNZIPQ $UNZIPV -l "$z" 1>/dev/null 2>&1
+  return $?
+}
+
+# be wary of busybox unzip
+# http://lists.busybox.net/pipermail/busybox/2010-August/073131.html
+case "$SFX_PAD:$SFX_UNZIP:$SFX_LOOP:$SFX_PIPE" in
+  :1:*:*)
+    echo "$CMD: testing for SFX support"
+    if ! _t ":" "$SHARABS"; then
+      echo "$CMD: *** SFX failed" 1>&2
+      SFX_UNZIP=
+    fi
+  ;;
+esac
+
+case "$SFX_PAD:$SFX_UNZIP:$SFX_LOOP:$SFX_PIPE" in
+  ::1:*)
+    echo "$CMD: testing for loopback support"
+    UNZIPLOOP=`losetup -f`
+    losetup -r -o $SFX_BYTES "$UNZIPLOOP" "$SHARABS"
+    if ! _t ":" "$UNZIPLOOP"; then
+      echo "$CMD: *** loopback failed" 1>&2
+      SFX_LOOP=
+    fi
+  ;;
+esac
+
+case "$SFX_PAD:$SFX_UNZIP:$SFX_LOOP:$SFX_PIPE" in
+  :::1)
+    echo "$CMD: testing for pipe support"
+    if ! _t "dd if=$SHARABS bs=$SFX_BLOCKSIZE skip=$SFX_BLOCKS" "-"; then
+      echo "$CMD: *** pipe failed" 1>&2
+      SFX_PIPE=
+    fi
+  ;;
+esac
+
+if test "$SFX_PAD"; then
+  echo "$CMD: copying file and resetting pad"
+  cp "$SHARABS" $workdir/onie-installer.zip
+  dd if="$SHARABS" of=$workdir/onie-installer.zip bs=512 skip=$(($SFX_BLOCKS-1)) count=1 conv=notrunc
+  _CAT=":"
+  _ZIP="$workdir/onie-installer.zip"
+elif test "$SFX_UNZIP"; then
+  echo "$CMD: processing SFX with unzip"
+  _CAT=":"
+  _ZIP="$SHARABS"
+elif test "$SFX_LOOP"; then
+  echo "$CMD: processing SFX with losetup"
+  _CAT=":"
+  _ZIP="$UNZIPLOOP"
+elif test "$SFX_PIPE"; then
+  echo "$CMD: processing SFX with dd"
+  _CAT="dd if=$SHARABS bs=$SFX_BLOCKSIZE skip=$SFX_BLOCKS"
+  _ZIP="-"
+else
+  echo "$CMD: *** copying file to find zip offset"
+  dd if=$SHARABS of=$workdir/onie-installer.zip bs=$SFX_BLOCKSIZE skip=$SFX_BLOCKS
+  _CAT=":"
+  _ZIP="$workdir/onie-installer.zip"
+fi
+
+if test "$mode" = "unzip"; then
+  echo "$CMD: processing with zip"
+
+  if test "$UNZIPDIR"; then
+    cd "$UNZIPDIR"
+  fi
+
+  $_CAT | $UNZIP $UNZIPQ $UNZIPV $UNZIPOPTS "$_ZIP" $UNZIPARGS
+  sts=$?
+  test $sts -eq 0 || exit $sts
+  
+  if test -f "$SFX_PERMS"; then
+    echo "$CMD: correcting permissions with $SFX_PERMS"
+    chmod +x "$SFX_PERMS"
+    ./"$SFX_PERMS"
+  fi
+
+  exit $sts
+fi
+
+if test "$mode" != "install"; then
+  echo "$CMD: *** invalid mode: $mode" 1>&2
+  exit 1
+fi
+
+if test "$UNZIPDIR"; then
+  :
+else
+  UNZIPDIR=$workdir
+fi
+
+banner=`unzip 2>&1` || :
+case "$banner" in
+  *"-t"*)
+    echo "$CMD: testing shar"
+    $_CAT | $UNZIP $UNZIPQ $UNZIPV $UNZIPOPTS -t "$_ZIP" $UNZIPARGS
+    sts=$?
+    test $sts -eq 0 || exit $sts
+  ;;
+esac
+
+echo "$CMD: computing checksum"
+{
+  dd if="$SHARABS" bs=$SFX_BLOCKSIZE count=$SFX_BLOCKS 2>/dev/null | sed -e "/^SFX_CHECKSUM=/d";
+  dd if="$SHARABS" bs=$SFX_BLOCKSIZE skip=$SFX_BLOCKS 2>/dev/null
+} | md5sum > "$UNZIPDIR/ck"
+
+set dummy `cat "$UNZIPDIR/ck"`
+newck=$2
+
+rm -f "$UNZIPDIR/ck"
+
+if test "$SFX_CHECKSUM" = "$newck"; then
+  echo "$CMD: checksum is OK"
+else
+  echo "$CMD: *** checksum mismatch" 1>&2
+  exit 1
+fi
+
+shardir=`dirname $0`
+shardir=`cd $shardir && pwd`
+
+echo "$CMD: extracting shar into $UNZIPDIR"
+cd $UNZIPDIR
+
+if test "$SFX_LAZY"; then
+  $_CAT | $UNZIP $UNZIPQ $UNZIPOPTS "$_ZIP" "$SFX_INSTALL"
+else
+  $_CAT | $UNZIP $UNZIPQ $UNZIPOPTS "$_ZIP" $UNZIPARGS
+fi
+
+if test -f "$SFX_PERMS"; then
+  echo "$CMD: correcting permissions with $SFX_PERMS"
+  chmod +x "$SFX_PERMS"
+  ./"$SFX_PERMS"
+fi
+
+if test -f "$SFX_INSTALL"; then
+  echo "$CMD: invoking installer $SFX_INSTALL"
+
+  tmp_install=`mktemp $UNZIPDIR/install-XXXXXX`
+  mv "$SFX_INSTALL" $tmp_install
+  chmod +x "$tmp_install"
+
+  export SFX_BLOCKSIZE SFX_BLOCKS SFX_PAD SFX_UNZIP SFX_LOOP SFX_PIPE SFX_LAZY SFX_PERMS
+
+  case "$-" in
+    *x*)
+      dashx="-x"
+    ;;
+  esac
+
+  if test -e "$_ZIP"; then
+    eval "$tmp_install" $dashx "$_ZIP"
+  else
+    eval "$tmp_install" $dashx "$SHARABS"
+  fi
+
+  exit $?
+else
+  echo "$CMD: *** missing installer: $SFX_INSTALL" 1>&2
+  exit 1
+fi
+
+##############################
+#
+# END OF SHAR HEADER
+#
+# BINARY ZIP DATA FOLLOWS
+#
+# DO NOT EDIT!
+#
+##############################