diff options
Diffstat (limited to 'Firebase/Utilities/Environment/third_party/GULAppEnvironmentUtil.m')
| -rw-r--r-- | Firebase/Utilities/Environment/third_party/GULAppEnvironmentUtil.m | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/Firebase/Utilities/Environment/third_party/GULAppEnvironmentUtil.m b/Firebase/Utilities/Environment/third_party/GULAppEnvironmentUtil.m new file mode 100644 index 0000000..e96ba70 --- /dev/null +++ b/Firebase/Utilities/Environment/third_party/GULAppEnvironmentUtil.m @@ -0,0 +1,236 @@ +// Copyright 2017 Google +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#import "GULAppEnvironmentUtil.h" + +#import <Foundation/Foundation.h> +#import <dlfcn.h> +#import <mach-o/dyld.h> +#import <sys/utsname.h> + +/// The encryption info struct and constants are missing from the iPhoneSimulator SDK, but not from +/// the iPhoneOS or Mac OS X SDKs. Since one doesn't ever ship a Simulator binary, we'll just +/// provide the definitions here. +#if TARGET_OS_SIMULATOR && !defined(LC_ENCRYPTION_INFO) +#define LC_ENCRYPTION_INFO 0x21 +struct encryption_info_command { + uint32_t cmd; + uint32_t cmdsize; + uint32_t cryptoff; + uint32_t cryptsize; + uint32_t cryptid; +}; +#endif + +@implementation GULAppEnvironmentUtil + +/// A key for the Info.plist to enable or disable checking if the App Store is running in a sandbox. +/// This will affect your data integrity when using Firebase Analytics, as it will disable some +/// necessary checks. +static NSString *const kFIRAppStoreReceiptURLCheckEnabledKey = + @"FirebaseAppStoreReceiptURLCheckEnabled"; + +/// The file name of the sandbox receipt. This is available on iOS >= 8.0 +static NSString *const kFIRAIdentitySandboxReceiptFileName = @"sandboxReceipt"; + +/// The following copyright from Landon J. Fuller applies to the isAppEncrypted function. +/// +/// Copyright (c) 2017 Landon J. Fuller <landon@landonf.org> +/// All rights reserved. +/// +/// Permission is hereby granted, free of charge, to any person obtaining a copy of this software +/// and associated documentation files (the "Software"), to deal in the Software without +/// restriction, including without limitation the rights to use, copy, modify, merge, publish, +/// distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the +/// Software is furnished to do so, subject to the following conditions: +/// +/// The above copyright notice and this permission notice shall be included in all copies or +/// substantial portions of the Software. +/// +/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING +/// BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +/// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, +/// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING +/// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +/// +/// Comment from <a href="http://iphonedevwiki.net/index.php/Crack_prevention">iPhone Dev Wiki +/// Crack Prevention</a>: +/// App Store binaries are signed by both their developer and Apple. This encrypts the binary so +/// that decryption keys are needed in order to make the binary readable. When iOS executes the +/// binary, the decryption keys are used to decrypt the binary into a readable state where it is +/// then loaded into memory and executed. iOS can tell the encryption status of a binary via the +/// cryptid structure member of LC_ENCRYPTION_INFO MachO load command. If cryptid is a non-zero +/// value then the binary is encrypted. +/// +/// 'Cracking' works by letting the kernel decrypt the binary then siphoning the decrypted data into +/// a new binary file, resigning, and repackaging. This will only work on jailbroken devices as +/// codesignature validation has been removed. Resigning takes place because while the codesignature +/// doesn't have to be valid thanks to the jailbreak, it does have to be in place unless you have +/// AppSync or similar to disable codesignature checks. +/// +/// More information at <a href="http://landonf.org/2009/02/index.html">Landon Fuller's blog</a> +static BOOL IsAppEncrypted() { + const struct mach_header *executableHeader = NULL; + for (uint32_t i = 0; i < _dyld_image_count(); i++) { + const struct mach_header *header = _dyld_get_image_header(i); + if (header && header->filetype == MH_EXECUTE) { + executableHeader = header; + break; + } + } + + if (!executableHeader) { + return NO; + } + + BOOL is64bit = (executableHeader->magic == MH_MAGIC_64); + uintptr_t cursor = (uintptr_t)executableHeader + + (is64bit ? sizeof(struct mach_header_64) : sizeof(struct mach_header)); + const struct segment_command *segmentCommand = NULL; + uint32_t i = 0; + + while (i++ < executableHeader->ncmds) { + segmentCommand = (struct segment_command *)cursor; + + if (!segmentCommand) { + continue; + } + + if ((!is64bit && segmentCommand->cmd == LC_ENCRYPTION_INFO) || + (is64bit && segmentCommand->cmd == LC_ENCRYPTION_INFO_64)) { + if (is64bit) { + struct encryption_info_command_64 *cryptCmd = + (struct encryption_info_command_64 *)segmentCommand; + return cryptCmd && cryptCmd->cryptid != 0; + } else { + struct encryption_info_command *cryptCmd = (struct encryption_info_command *)segmentCommand; + return cryptCmd && cryptCmd->cryptid != 0; + } + } + cursor += segmentCommand->cmdsize; + } + + return NO; +} + +static BOOL HasSCInfoFolder() { +#if TARGET_OS_IOS || TARGET_OS_TV + NSString *bundlePath = [NSBundle mainBundle].bundlePath; + NSString *scInfoPath = [bundlePath stringByAppendingPathComponent:@"SC_Info"]; + return [[NSFileManager defaultManager] fileExistsAtPath:scInfoPath]; +#elif TARGET_OS_OSX + return NO; +#endif +} + +static BOOL HasEmbeddedMobileProvision() { +#if TARGET_OS_IOS || TARGET_OS_TV + return [[NSBundle mainBundle] pathForResource:@"embedded" ofType:@"mobileprovision"].length > 0; +#elif TARGET_OS_OSX + return NO; +#endif +} + ++ (BOOL)isFromAppStore { + static dispatch_once_t isEncryptedOnce; + static BOOL isEncrypted = NO; + + dispatch_once(&isEncryptedOnce, ^{ + isEncrypted = IsAppEncrypted(); + }); + + if ([GULAppEnvironmentUtil isSimulator]) { + return NO; + } + + // If an app contain the sandboxReceipt file, it means its coming from TestFlight + // This must be checked before the SCInfo Folder check below since TestFlight apps may + // also have an SCInfo folder. + if ([GULAppEnvironmentUtil isAppStoreReceiptSandbox]) { + return NO; + } + + if (HasSCInfoFolder()) { + // When iTunes downloads a .ipa, it also gets a customized .sinf file which is added to the + // main SC_Info directory. + return YES; + } + + // For iOS >= 8.0, iTunesMetadata.plist is moved outside of the sandbox. Any attempt to read + // the iTunesMetadata.plist outside of the sandbox will be rejected by Apple. + // If the app does not contain the embedded.mobileprovision which is stripped out by Apple when + // the app is submitted to store, then it is highly likely that it is from Apple Store. + return isEncrypted && !HasEmbeddedMobileProvision(); +} + ++ (BOOL)isAppStoreReceiptSandbox { + // Since checking the App Store's receipt URL can be memory intensive, check the option in the + // Info.plist if developers opted out of this check. + id enableSandboxCheck = + [[NSBundle mainBundle] objectForInfoDictionaryKey:kFIRAppStoreReceiptURLCheckEnabledKey]; + if (enableSandboxCheck && [enableSandboxCheck isKindOfClass:[NSNumber class]] && + ![enableSandboxCheck boolValue]) { + return NO; + } + + NSURL *appStoreReceiptURL = [NSBundle mainBundle].appStoreReceiptURL; + NSString *appStoreReceiptFileName = appStoreReceiptURL.lastPathComponent; + return [appStoreReceiptFileName isEqualToString:kFIRAIdentitySandboxReceiptFileName]; +} + ++ (BOOL)isSimulator { +#if TARGET_OS_IOS || TARGET_OS_TV + NSString *platform = [GULAppEnvironmentUtil deviceModel]; + return [platform isEqual:@"x86_64"] || [platform isEqual:@"i386"]; +#elif TARGET_OS_OSX + return NO; +#endif +} + ++ (NSString *)deviceModel { + static dispatch_once_t once; + static NSString *deviceModel; + + dispatch_once(&once, ^{ + struct utsname systemInfo; + if (uname(&systemInfo) == 0) { + deviceModel = [NSString stringWithUTF8String:systemInfo.machine]; + } + }); + return deviceModel; +} + ++ (NSString *)systemVersion { + // Assemble the systemVersion, excluding the patch version if it's 0. + NSOperatingSystemVersion osVersion = [NSProcessInfo processInfo].operatingSystemVersion; + NSMutableString *versionString = [[NSMutableString alloc] + initWithFormat:@"%ld.%ld", (long)osVersion.majorVersion, (long)osVersion.minorVersion]; + if (osVersion.patchVersion != 0) { + [versionString appendFormat:@".%ld", (long)osVersion.patchVersion]; + } + + return versionString; +} + ++ (BOOL)isAppExtension { +#if TARGET_OS_IOS || TARGET_OS_TV + // Documented by <a href="https://goo.gl/RRB2Up">Apple</a> + BOOL appExtension = [[[NSBundle mainBundle] bundlePath] hasSuffix:@".appex"]; + return appExtension; +#elif TARGET_OS_OSX + return NO; +#endif +} + +@end |