Initial dmgutils implementation

code/cli/munki/munki.xcodeproj/project.pbxproj

@@ -19,6 +19,9 @@
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 		C01364522C311DFA008DB215 /* ArgumentParser in Frameworks */ = {isa = PBXBuildFile; productRef = C01364512C311DFA008DB215 /* ArgumentParser */; };
+		C01364542C321FE7008DB215 /* dmgutils.swift in Sources */ = {isa = PBXBuildFile; fileRef = C01364532C321FE7008DB215 /* dmgutils.swift */; };
+		C01364552C321FE7008DB215 /* dmgutils.swift in Sources */ = {isa = PBXBuildFile; fileRef = C01364532C321FE7008DB215 /* dmgutils.swift */; };
+		C01364562C321FE7008DB215 /* dmgutils.swift in Sources */ = {isa = PBXBuildFile; fileRef = C01364532C321FE7008DB215 /* dmgutils.swift */; };
 		C07A6FA92C2A82B400090743 /* managedsoftwareupdate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C07A6FA82C2A82B400090743 /* managedsoftwareupdate.swift */; };
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@@ -75,6 +78,7 @@
 		C01364422C2DD1BA008DB215 /* plistutils.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = plistutils.swift; sourceTree = "<group>"; };
 		C01364482C2F8EFE008DB215 /* GitFileRepo.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GitFileRepo.swift; sourceTree = "<group>"; };
 		C013644C2C30F5D8008DB215 /* RepoFactory.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RepoFactory.swift; sourceTree = "<group>"; };
+		C01364532C321FE7008DB215 /* dmgutils.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = dmgutils.swift; sourceTree = "<group>"; };
 		C07A6FA52C2A82B400090743 /* managedsoftwareupdate */ = {isa = PBXFileReference; explicitFileType = "compiled.mach-o.executable"; includeInIndex = 0; path = managedsoftwareupdate; sourceTree = BUILT_PRODUCTS_DIR; };
 		C07A6FA82C2A82B400090743 /* managedsoftwareupdate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = managedsoftwareupdate.swift; sourceTree = "<group>"; };
 		C07A6FAF2C2B22A400090743 /* prefs.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = prefs.swift; sourceTree = "<group>"; };
@@ -197,6 +201,7 @@
 				C07A6FD12C2B654300090743 /* utils.swift */,
 				C07A6FD92C2CF19600090743 /* cliutils.swift */,
 				C01364422C2DD1BA008DB215 /* plistutils.swift */,
+				C01364532C321FE7008DB215 /* dmgutils.swift */,
 			);
 			path = shared;
 			sourceTree = "<group>";
@@ -315,6 +320,7 @@
 				C07A6FB02C2B22A400090743 /* prefs.swift in Sources */,
 				C07A6FA92C2A82B400090743 /* managedsoftwareupdate.swift in Sources */,
 				C07A6FB22C2B22D300090743 /* constants.swift in Sources */,
+				C01364542C321FE7008DB215 /* dmgutils.swift in Sources */,
 				C07A6FD22C2B654300090743 /* utils.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -325,6 +331,7 @@
 			files = (
 				C01364442C2DD1BA008DB215 /* plistutils.swift in Sources */,
 				C01364462C2E051F008DB215 /* makecatalogslib.swift in Sources */,
+				C01364552C321FE7008DB215 /* dmgutils.swift in Sources */,
 				C07A6FDB2C2CF19600090743 /* cliutils.swift in Sources */,
 				C013644E2C30F5D8008DB215 /* RepoFactory.swift in Sources */,
 				C07A6FBE2C2B5AF000090743 /* prefs.swift in Sources */,
@@ -343,6 +350,7 @@
 			files = (
 				C07A6FDC2C2CF19600090743 /* cliutils.swift in Sources */,
 				C01364452C2DD1BA008DB215 /* plistutils.swift in Sources */,
+				C01364562C321FE7008DB215 /* dmgutils.swift in Sources */,
 				C07A6FCB2C2B5C3A00090743 /* prefs.swift in Sources */,
 				C013644F2C30F5D8008DB215 /* RepoFactory.swift in Sources */,
 				C07A6FC72C2B5C0700090743 /* makecatalogs.swift in Sources */,

code/cli/munki/shared/dmgutils.swift

@@ -0,0 +1,222 @@
+//
+//  dmgutils.swift
+//  munki
+//
+//  Created by Greg Neagle on 6/30/24.
+//
+
+import Foundation
+
+func hdiutilData(arguments: [String], stdIn: String = "") -> PlistDict {
+    // runs an hdiutil <command> on a dmg and attempts to return a plist data structure
+    var hdiUtilArgs = arguments
+    if !hdiUtilArgs.contains("-plist") {
+        hdiUtilArgs.append("-plist")
+    }
+    let results = runCLI("/usr/bin/hdiutil", arguments: hdiUtilArgs, stdIn: stdIn)
+    if results.exitcode != 0 {
+        //TODO: implement Munki's display* methods
+        printStderr("hdiutil error \(results.error) with arguments \(arguments)")
+    }
+    let (plistStr, _) = parseFirstPlist(fromString: results.output)
+    if !plistStr.isEmpty {
+        do {
+            if let plist = try readPlistFromString(plistStr) as? PlistDict {
+                return plist
+            }
+        } catch {
+            return PlistDict()
+        }
+    }
+    return PlistDict()
+}
+
+func dmgImageInfo(_ dmgPath: String) -> PlistDict {
+    // runs hdiutil imageinfo on a dmg and returns a plist data structure
+    return hdiutilData(arguments: ["imageinfo", dmgPath])
+}
+
+
+func dmgIsWritable(_ dmgPath: String) -> Bool {
+    // Attempts to determine if the given disk image is writable
+    let imageInfo = dmgImageInfo(dmgPath)
+    if let format = imageInfo["Format"] as? String {
+        if ["UDSB", "UDSP", "UDRW", "RdWr"].contains(format) {
+            return true
+        }
+    }
+    return false
+}
+
+
+func dmgHasSLA(_ dmgPath: String) -> Bool {
+    // Returns true if dmg has a Software License Agreement.
+    // These dmgs normally cannot be attached without user intervention
+    let imageInfo = dmgImageInfo(dmgPath)
+    if let properties = imageInfo["Properties"] as? PlistDict {
+        if let hasSLA = properties["Software License Agreement"] as? Bool {
+            return hasSLA
+        }
+    }
+    return false
+}
+
+
+func hdiutilInfo() -> PlistDict {
+    // runs hdiutil info on a dmg and returns a plist data structure
+    return hdiutilData(arguments: ["info"])
+}
+
+
+func pathIsVolumeMountPoint(_ path: String) -> Bool {
+    // Returns a boolean to indicate if path is a mountpoint for a disk image
+    let info = hdiutilInfo()
+    if let images = info["images"] as? [PlistDict] {
+        // "images" is an array of dicts
+        for image in images {
+            if let systemEntities = image["system-entities"] as? [PlistDict] {
+                // "system-entities" is an array of dicts
+                for entity in systemEntities {
+                    if let mountpoint = entity["mount-point"] as? String {
+                        // there's a mount-point for this!
+                        if path == mountpoint {
+                            // our path is this mountpoint
+                            return true
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return false
+}
+
+
+func diskImageForMountPoint(_ path: String) -> String? {
+    // Attempts to find the path to a dmg for a given mount point
+    let info = hdiutilInfo()
+    if let images = info["images"] as? [PlistDict] {
+        // "images" is an array of dicts
+        for image in images {
+            if let imagePath = image["image-path"] as? String {
+                if let systemEntities = image["system-entities"] as? [PlistDict] {
+                    // "system-entities" is an array of dicts
+                    for entity in systemEntities {
+                        if let mountpoint = entity["mount-point"] as? String {
+                            // there's a mount-point for this!
+                            if path == mountpoint {
+                                // our path is this mountpoint
+                                return imagePath
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return nil
+}
+
+func mountPointsForDiskImage(_ dmgPath: String) -> [String] {
+    // returns a list of mountpoints for the given disk image
+    var mountpoints = [String]()
+    let info = hdiutilInfo()
+    if let images = info["images"] as? [PlistDict] {
+        // "images" is an array of dicts
+        for image in images {
+            if let imagePath = image["image-path"] as? String {
+                // "image-path" is path to dmg file
+                if imagePath == dmgPath {
+                    // this is our disk image
+                    if let systemEntities = image["system-entities"] as? [PlistDict] {
+                        // "system-entities" is an array of dicts
+                        for entity in systemEntities {
+                            if let mountpoint = entity["mount-point"] as? String {
+                                // there's a mount-point for this!
+                                mountpoints.append(mountpoint)
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return mountpoints
+}
+
+
+func diskImageIsMounted(_ dmgPath: String) -> Bool {
+    // Returns true if the given disk image is currently mounted
+    return !mountPointsForDiskImage(dmgPath).isEmpty
+}
+
+
+func mountdmg(
+    _ dmgPath: String,
+    useShadow: Bool = false,
+    useExistingMounts: Bool = false,
+    randomMountpoint: Bool = true,
+    skipVerification: Bool = false) -> [String]
+{
+    // Attempts to mount the dmg at dmgpath
+    // and returns a list of mountpoints
+    // If use_shadow is true, mount image with shadow file
+    // If random_mountpoint, mount at random dir under /tmp
+    var mountpoints = [String]()
+    let dmgName = (dmgPath as NSString).lastPathComponent
+    
+    if useExistingMounts {
+        if diskImageIsMounted(dmgPath) {
+            return mountPointsForDiskImage(dmgPath)
+        }
+    }
+    
+    // attempt to mount the dmg
+    var stdIn = ""
+    if dmgHasSLA(dmgPath) {
+        stdIn = "Y\n"
+        // TODO: implement Munki display* methods
+        print("NOTE: \(dmgName) has embedded Software License Agreement")
+    }
+    var arguments = ["attach", dmgPath, "-nobrowse"]
+    if randomMountpoint {
+        arguments += ["-mountRandom", "/tmp"]
+    }
+    if useShadow {
+        arguments.append("-shadow")
+    }
+    if skipVerification {
+        arguments.append("-noverify")
+    }
+    let plistData = hdiutilData(arguments: arguments, stdIn: stdIn)
+    if let systemEntities = plistData["system-entities"] as? [PlistDict] {
+        for entity in systemEntities {
+            if let mountPoint = entity["mount-point"] as? String {
+                mountpoints.append(mountPoint)
+            }
+        }
+    } else {
+        // TODO: implement Munki display* methods
+        printStderr("Could not get mountpoint info from results of hdiutil attach \(dmgName)")
+    }
+    return mountpoints
+}
+
+func unmountdmg(_ mountpoint: String) {
+    // Unmounts the dmg at mountpoint
+    var arguments = ["detach", mountpoint]
+    let results = runCLI("/usr/bin/hdiutil", arguments: arguments)
+    if results.exitcode != 0 {
+        // regular unmount failed; try to force unmount
+        // TODO: implement Munki display* methods
+        printStderr("Polite unmount failed: \(results.error)")
+        printStderr("Attempting to force unmount \(mountpoint)")
+        arguments.append("-force")
+        let results = runCLI("/usr/bin/hdiutil", arguments: arguments)
+        if results.exitcode != 0 {
+            // TODO: implement Munki display* methods
+            print("WARNING: Failed to unmount \(mountpoint): \(results.error)")
+        }
+    }
+}
+

code/cli/munki/shared/utils.swift

@@ -12,3 +12,35 @@ func getVersion() -> String {
     // or figure out a way to update this at build time
     return "0.0.1"
 }
+
+func parseFirstPlist(fromString str: String) -> (String, String) {
+    // Parses a string, looking for the first thing that looks like a plist.
+    // Returns two strings. The first will be a string representaion of a plist (or empty)
+    // The second is any characters remaining after the found plist
+    let header = "<?xml version"
+    let footer = "</plist>"
+    let headerRange = (str as NSString).range(of: header)
+    if headerRange.location == NSNotFound {
+        // header not found
+        return ("", str)
+    }
+    let footerSearchIndex = headerRange.location + headerRange.length
+    let footerSearchRange = NSRange(
+        location: footerSearchIndex,
+        length: str.count - footerSearchIndex
+    )
+    let footerRange = (str as NSString).range(of: footer, range: footerSearchRange)
+    if footerRange.location == NSNotFound {
+        // footer not found
+        return ("", str)
+    }
+    let plistRange = NSRange(
+        location: headerRange.location,
+        length: footerRange.location + footerRange.length - headerRange.location
+    )
+    let plistStr = (str as NSString).substring(with: plistRange)
+    let remainderIndex = plistRange.location + plistRange.length
+    let remainder = (str as NSString).substring(from: remainderIndex)
+    return(plistStr, remainder)
+}
+