Next Previous

SMJobBlessUtil.py

#! /usr/bin/python

#   File:       SMJobBlessUtil.py

#   Contains:   Tool for checking and correcting apps that use SMJobBless.

#   Written by: DTS

#   Copyright:  Copyright (c) 2012 Apple Inc. All Rights Reserved.

#   Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Inc.

#               ("Apple") in consideration of your agreement to the following

#               terms, and your use, installation, modification or

#               redistribution of this Apple software constitutes acceptance of

#               these terms.  If you do not agree with these terms, please do

#               not use, install, modify or redistribute this Apple software.

#               In consideration of your agreement to abide by the following

#               terms, and subject to these terms, Apple grants you a personal,

#               non-exclusive license, under Apple's copyrights in this

#               original Apple software (the "Apple Software"), to use,

#               reproduce, modify and redistribute the Apple Software, with or

#               without modifications, in source and/or binary forms; provided

#               that if you redistribute the Apple Software in its entirety and

#               without modifications, you must retain this notice and the

#               following text and disclaimers in all such redistributions of

#               the Apple Software. Neither the name, trademarks, service marks

#               or logos of Apple Inc. may be used to endorse or promote

#               products derived from the Apple Software without specific prior

#               written permission from Apple.  Except as expressly stated in

#               this notice, no other rights or licenses, express or implied,

#               are granted by Apple herein, including but not limited to any

#               patent rights that may be infringed by your derivative works or

#               by other works in which the Apple Software may be incorporated.

#               The Apple Software is provided by Apple on an "AS IS" basis.

#               APPLE MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING

#               WITHOUT LIMITATION THE IMPLIED WARRANTIES OF NON-INFRINGEMENT,

#               MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, REGARDING

#               THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN

#               COMBINATION WITH YOUR PRODUCTS.

#               IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT,

#               INCIDENTAL OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED

#               TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

#               DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ARISING IN ANY WAY

#               OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION

#               OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY

#               OF CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR

#               OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF

#               SUCH DAMAGE.

import sys

import os

import getopt

import subprocess

import plistlib

import operator

class UsageException (Exception):

"""

    Raised when the progam detects a usage issue; the top-level code catches this

    and prints a usage message.

"""

    pass

class CheckException (Exception):

"""

    Raised when the "check" subcommand detects a problem; the top-level code catches

    this and prints a nice error message.

"""

    def __init__(self, message, path=None):

        self.message = message

        self.path = path

def checkCodeSignature(programPath, programType):

    """Checks the code signature of the referenced program."""

    # Use the codesign tool to check the signature.  The second "-v" is required to enable

    # verbose mode, which causes codesign to do more checking.  By default it does the minimum

    # amount of checking ("Is the program properly signed?").  If you enabled verbose mode it

    # does other sanity checks, which we definitely want.  The specific thing I'd like to

    # detect is "Does the code satisfy its own designated requirement?" and I need to enable

    # verbose mode to get that.

    args = [

        # "false",

        "codesign",

        "-v",

        "-v",

        programPath

    try:

        subprocess.check_call(args, stderr=open("/dev/null"))

    except subprocess.CalledProcessError, e:

        raise CheckException("%s code signature invalid" % programType, programPath)

def readDesignatedRequirement(programPath, programType):

    """Returns the designated requirement of the program as a string."""

    args = [

        # "false",

        "codesign",

        "-d",

        "-r",

        "-",

        programPath

    try:

        req = subprocess.check_output(args, stderr=open("/dev/null"))

    except subprocess.CalledProcessError, e:

        raise CheckException("%s designated requirement unreadable" % programType, programPath)

    reqLines = req.splitlines()

    if len(reqLines) != 1 or not req.startswith("designated => "):

        raise CheckException("%s designated requirement malformed" % programType, programPath)

    return reqLines[0][len("designated => "):]

def readInfoPlistFromPath(infoPath):

    """Reads an "Info.plist" file from the specified path."""

    try:

        info = plistlib.readPlist(infoPath)

    except:

        raise CheckException("'Info.plist' not readable", infoPath)

    if not isinstance(info, dict):

        raise CheckException("'Info.plist' root must be a dictionary", infoPath)

    return info

def readPlistFromToolSection(toolPath, segmentName, sectionName):

    """Reads a dictionary property list from the specified section within the specified executable."""

    # Run otool -s to get a hex dump of the section.

    args = [

        # "false",

        "otool",

        "-s",

        segmentName,

        sectionName,

        toolPath

    try:

        plistDump = subprocess.check_output(args)

    except subprocess.CalledProcessError, e:

        raise CheckException("tool %s / %s section unreadable" % (segmentName, sectionName), toolPath)

    # Convert that hex dump to an property list.

    plistLines = plistDump.splitlines()

    if len(plistLines) < 3 or plistLines[1] != ("Contents of (%s,%s) section" % (segmentName, sectionName)):

        raise CheckException("tool %s / %s section dump malformed (1)" % (segmentName, sectionName), toolPath)

    del plistLines[0:2]

    try:

        bytes = []

        for line in plistLines:

            # line looks like this:

            # '0000000100000b80\t3c 3f 78 6d 6c 20 76 65 72 73 69 6f 6e 3d 22 31 '

            columns = line.split("\t")

            assert len(columns) == 2

            for hexStr in columns[1].split():

                bytes.append(int(hexStr, 16))

        plist = plistlib.readPlistFromString(bytearray(bytes))

    except:

        raise CheckException("tool %s / %s section dump malformed (2)" % (segmentName, sectionName), toolPath)

    # Check the root of the property list.

    if not isinstance(plist, dict):

        raise CheckException("tool %s / %s property list root must be a dictionary" % (segmentName, sectionName), toolPath)

    return plist

def checkStep1(appPath):

    """Checks that the app and the tool are both correctly code signed."""

    if not os.path.isdir(appPath):

        raise CheckException("app not found", appPath)

    # Check the app's code signature.

    checkCodeSignature(appPath, "app")

    # Check the tool directory.

    toolDirPath = os.path.join(appPath, "Contents", "Library", "LaunchServices")

    if not os.path.isdir(toolDirPath):

        raise CheckException("tool directory not found", toolDirPath)

    # Check each tool's code signature.

    toolPathList = []

    for toolName in os.listdir(toolDirPath):

        if toolName != ".DS_Store":

            toolPath = os.path.join(toolDirPath, toolName)

            if not os.path.isfile(toolPath):

                raise CheckException("tool directory contains a directory", toolPath)

            checkCodeSignature(toolPath, "tool")

            toolPathList.append(toolPath)

    # Check that we have at least one tool.

    if len(toolPathList) == 0:

        raise CheckException("no tools found", toolDirPath)

    return toolPathList

def checkStep2(appPath, toolPathList):

    """Checks the SMPrivilegedExecutables entry in the app's "Info.plist"."""

    # Create a map from the tool name (not path) to its designated requirement.

    toolNameToReqMap = dict()

    for toolPath in toolPathList:

        req = readDesignatedRequirement(toolPath, "tool")

        toolNameToReqMap[os.path.basename(toolPath)] = req

    # Read the Info.plist for the app and extract the SMPrivilegedExecutables value.

    infoPath = os.path.join(appPath, "Contents", "Info.plist")

    info = readInfoPlistFromPath(infoPath)

    if not info.has_key("SMPrivilegedExecutables"):

        raise CheckException("'SMPrivilegedExecutables' not found", infoPath)

    infoToolDict = info["SMPrivilegedExecutables"]

    if not isinstance(infoToolDict, dict):

        raise CheckException("'SMPrivilegedExecutables' must be a dictionary", infoPath)

    # Check that the list of tools matches the list of SMPrivilegedExecutables entries.

    if sorted(infoToolDict.keys()) != sorted(toolNameToReqMap.keys()):

        raise CheckException("'SMPrivilegedExecutables' and tools in 'Contents/Library/LaunchServices' don't match")

    # Check that all the requirements match.

    # This is an interesting policy choice.  Technically the tool just needs to match

    # the requirement listed in SMPrivilegedExecutables, and we can check that by

    # putting the requirement into tmp.req and then running

    # $ codesign -v -R tmp.req /path/to/tool

    # However, for a Developer ID signed tool we really want to have the SMPrivilegedExecutables

    # entry contain the tool's designated requirement because Xcode has built a

    # more complex DR that does lots of useful and important checks.  So, as a matter

    # of policy we require that the value in SMPrivilegedExecutables match the tool's DR.

    for toolName in infoToolDict:

        if infoToolDict[toolName] != toolNameToReqMap[toolName]:

            raise CheckException("tool designated requirement (%s) doesn't match entry in 'SMPrivilegedExecutables' (%s)" % (toolNameToReqMap[toolName], infoToolDict[toolName]))

def checkStep3(appPath, toolPathList):

    """Checks the "Info.plist" embedded in each helper tool."""

    # First get the app's designated requirement.

    appReq = readDesignatedRequirement(appPath, "app")

    # Then check that the tool's SMAuthorizedClients value matches it.

    for toolPath in toolPathList:

        info = readPlistFromToolSection(toolPath, "__TEXT", "__info_plist")

        if not info.has_key("CFBundleInfoDictionaryVersion") or info["CFBundleInfoDictionaryVersion"] != "6.0":

            raise CheckException("'CFBundleInfoDictionaryVersion' in tool __TEXT / __info_plist section must be '6.0'", toolPath)

        if not info.has_key("CFBundleIdentifier") or info["CFBundleIdentifier"] != os.path.basename(toolPath):

            raise CheckException("'CFBundleIdentifier' in tool __TEXT / __info_plist section must match tool name", toolPath)

        if not info.has_key("SMAuthorizedClients"):

            raise CheckException("'SMAuthorizedClients' in tool __TEXT / __info_plist section not found", toolPath)

        infoClientList = info["SMAuthorizedClients"]

        if not isinstance(infoClientList, list):

            raise CheckException("'SMAuthorizedClients' in tool __TEXT / __info_plist section must be an array", toolPath)

        if len(infoClientList) != 1:

            raise CheckException("'SMAuthorizedClients' in tool __TEXT / __info_plist section must have one entry", toolPath)

        # Again, as a matter of policy we require that the SMAuthorizedClients entry must

        # match exactly the designated requirement of the app.

        if infoClientList[0] != appReq:

            raise CheckException("app designated requirement (%s) doesn't match entry in 'SMAuthorizedClients' (%s)" % (appReq, infoClientList[0]), toolPath)

def checkStep4(appPath, toolPathList):

    """Checks the "launchd.plist" embedded in each helper tool."""

    for toolPath in toolPathList:

        launchd = readPlistFromToolSection(toolPath, "__TEXT", "__launchd_plist")

        if not launchd.has_key("Label") or launchd["Label"] != os.path.basename(toolPath):

            raise CheckException("'Label' in tool __TEXT / __launchd_plist section must match tool name", toolPath)

        # We don't need to check that the label matches the bundle identifier because

        # we know it matches the tool name and step 4 checks that the tool name matches

        # the bundle identifier.

def checkStep5(appPath):

    """There's nothing to do here; we effectively checked for this is steps 1 and 2."""

    pass

def check(appPath):

    """Checks the SMJobBless setup of the specified app."""

    # Each of the following steps matches a bullet point in the SMJobBless header doc.

    toolPathList = checkStep1(appPath)

    checkStep2(appPath, toolPathList)

    checkStep3(appPath, toolPathList)

    checkStep4(appPath, toolPathList)

    checkStep5(appPath)

def setreq(appPath, appInfoPlistPath, toolInfoPlistPaths):

"""

    Reads information from the built app and uses it to set the SMJobBless setup

    in the specified app and tool Info.plist source files.

"""

    if not os.path.isdir(appPath):

        raise CheckException("app not found", appPath)

    if not os.path.isfile(appInfoPlistPath):

        raise CheckException("app 'Info.plist' not found", appInfoPlistPath)

    for toolInfoPlistPath in toolInfoPlistPaths:

        if not os.path.isfile(toolInfoPlistPath):

            raise CheckException("app 'Info.plist' not found", toolInfoPlistPath)

    # Get the designated requirement for the app and each of the tools.

    appReq = readDesignatedRequirement(appPath, "app")

    toolDirPath = os.path.join(appPath, "Contents", "Library", "LaunchServices")

    if not os.path.isdir(toolDirPath):

        raise CheckException("tool directory not found", toolDirPath)

    toolNameToReqMap = {}

    for toolName in os.listdir(toolDirPath):

        req = readDesignatedRequirement(os.path.join(toolDirPath, toolName), "tool")

        toolNameToReqMap[toolName] = req

    if len(toolNameToReqMap) > len(toolInfoPlistPaths):

        raise CheckException("tool directory has more tools (%d) than you've supplied tool 'Info.plist' paths (%d)" % (len(toolNameToReqMap), len(toolInfoPlistPaths)), toolDirPath)

    if len(toolNameToReqMap) < len(toolInfoPlistPaths):

        raise CheckException("tool directory has fewer tools (%d) than you've supplied tool 'Info.plist' paths (%d)" % (len(toolNameToReqMap), len(toolInfoPlistPaths)), toolDirPath)

    # Build the new value for SMPrivilegedExecutables.

    appToolDict = {}

    toolInfoPlistPathToToolInfoMap = {}

    for toolInfoPlistPath in toolInfoPlistPaths:

        toolInfo = readInfoPlistFromPath(toolInfoPlistPath)

        toolInfoPlistPathToToolInfoMap[toolInfoPlistPath] = toolInfo

        if not toolInfo.has_key("CFBundleIdentifier"):

            raise CheckException("'CFBundleIdentifier' not found", toolInfoPlistPath)

        bundleID = toolInfo["CFBundleIdentifier"]

        if not isinstance(bundleID, basestring):

            raise CheckException("'CFBundleIdentifier' must be a string", toolInfoPlistPath)

        appToolDict[bundleID] = toolNameToReqMap[bundleID]

    # Set the SMPrivilegedExecutables value in the app "Info.plist".

    appInfo = readInfoPlistFromPath(appInfoPlistPath)

    needsUpdate = not appInfo.has_key("SMPrivilegedExecutables")

    if not needsUpdate:

        oldAppToolDict = appInfo["SMPrivilegedExecutables"]

        if not isinstance(oldAppToolDict, dict):

            raise CheckException("'SMPrivilegedExecutables' must be a dictionary", appInfoPlistPath)

        appToolDictSorted = sorted(appToolDict.iteritems(), key=operator.itemgetter(0))

        oldAppToolDictSorted = sorted(oldAppToolDict.iteritems(), key=operator.itemgetter(0))

        needsUpdate = (appToolDictSorted != oldAppToolDictSorted)

    if needsUpdate:

        appInfo["SMPrivilegedExecutables"] = appToolDict

        plistlib.writePlist(appInfo, appInfoPlistPath)

        print >> sys.stdout, "%s: updated" % appInfoPlistPath

    # Set the SMAuthorizedClients value in each tool's "Info.plist".

    toolAppListSorted = [ appReq ]      # only one element, so obviously sorted (-:

    for toolInfoPlistPath in toolInfoPlistPaths:

        toolInfo = toolInfoPlistPathToToolInfoMap[toolInfoPlistPath]

        needsUpdate = not toolInfo.has_key("SMAuthorizedClients")

        if not needsUpdate:

            oldToolAppList = toolInfo["SMAuthorizedClients"]

            if not isinstance(oldToolAppList, list):

                raise CheckException("'SMAuthorizedClients' must be an array", toolInfoPlistPath)

            oldToolAppListSorted = sorted(oldToolAppList)

            needsUpdate = (toolAppListSorted != oldToolAppListSorted)

        if needsUpdate:

            toolInfo["SMAuthorizedClients"] = toolAppListSorted

            plistlib.writePlist(toolInfo, toolInfoPlistPath)

            print >> sys.stdout, "%s: updated" % toolInfoPlistPath

def main():

    options, appArgs = getopt.getopt(sys.argv[1:], "d")

    debug = False

    for opt, val in options:

        if opt == "-d":

            debug = True

        else:

            raise UsageException()

    if len(appArgs) == 0:

        raise UsageException()

    command = appArgs[0]

    if command == "check":

        if len(appArgs) != 2:

            raise UsageException()

        check(appArgs[1])

    elif command == "setreq":

        if len(appArgs) < 4:

            raise UsageException()

        setreq(appArgs[1], appArgs[2], appArgs[3:])

    else:

        raise UsageException()

if __name__ == "__main__":

    try:

        main()

    except CheckException, e:

        if e.path is None:

            print >> sys.stderr, "%s: %s" % (os.path.basename(sys.argv[0]), e.message)

        else:

            path = e.path

            if path.endswith("/"):

                path = path[:-1]

            print >> sys.stderr, "%s: %s" % (path, e.message)

        sys.exit(1)

    except UsageException, e:

        print >> sys.stderr, "usage: %s check  /path/to/app" % os.path.basename(sys.argv[0])

        print >> sys.stderr, "       %s setreq /path/to/app /path/to/app/Info.plist /path/to/tool/Info.plist..." % os.path.basename(sys.argv[0])

        sys.exit(1)

Next Previous