Replace OpenSSL with Apple's CommonCrypto for session file decryption (fixes #2223)

This also removes the dependency on OpenSSL.

4 files changed, 148 insertions, 33 deletions

diff --git a/Source/SPDataAdditions.h b/Source/SPDataAdditions.h
index 6c404b9e..5158c270 100644
--- a/Source/SPDataAdditions.h
+++ b/Source/SPDataAdditions.h
@@ -35,6 +35,7 @@
 - (NSData *)dataEncryptedWithPassword:(NSString *)password;
 - (NSData *)dataEncryptedWithKey:(NSData *)aesKey IV:(NSData *)iv;
 - (NSData *)dataDecryptedWithPassword:(NSString *)password;
+- (NSData *)dataDecryptedWithKey:(NSData *)key;
 
 - (NSData *)compress;
 - (NSData *)decompress;
diff --git a/Source/SPDataAdditions.m b/Source/SPDataAdditions.m
index 4a07c437..8002595c 100644
--- a/Source/SPDataAdditions.m
+++ b/Source/SPDataAdditions.m
@@ -35,7 +35,6 @@
 #import "SPDataAdditions.h"
 
 #include <zlib.h>
-#include <openssl/aes.h>
 #include <CommonCrypto/CommonCrypto.h>
 #include <stdlib.h>
 
@@ -172,23 +171,50 @@ uint32_t LimitUInt32(NSUInteger i);
 - (NSData *)dataDecryptedWithPassword:(NSString *)password
 {
 	// Create the key from the password hash
-	NSData *passwordDigest = [[password dataUsingEncoding:NSUTF8StringEncoding] sha1Hash];
+	NSData *passwordDigest = [[[password dataUsingEncoding:NSUTF8StringEncoding] sha1Hash] subdataWithRange:NSMakeRange(0, kCCKeySizeAES128)];
+	
+	return [self dataDecryptedWithKey:passwordDigest];
 
-	// AES-128-cbc decrypt the data
-	AES_KEY aesKey;
-	AES_set_decrypt_key([passwordDigest bytes], 128, &aesKey);
+}
+
+- (NSData *)dataDecryptedWithKey:(NSData *)aesKey
+{
+	if([aesKey length] != kCCKeySizeAES128)
+		@throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"Key length invalid. Must be kCCKeySizeAES128 bytes!" userInfo:nil];
+	
+	if([self length] < (2*kCCBlockSizeAES128) || [self length] > UINT32_MAX)
+		@throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"Length of encrypted NSData must be in range 32 to 2^32!" userInfo:nil];
 
 	// Total length = encrypted length + IV
-	NSInteger totalLength = [self length];
-	NSInteger encryptedLength = totalLength - 16;
+	NSUInteger totalLength = [self length];
+	NSUInteger encryptedLength = totalLength - kCCBlockSizeAES128; // >=0 ensured above
 
 	// Take the IV from the first 128-bit block
-	unsigned char iv[16];
-	memcpy(iv, [self bytes], 16);
+	unsigned char iv[kCCBlockSizeAES128];
+	memcpy(iv, [self bytes], kCCBlockSizeAES128);
 
 	// Decrypt the data
-	unsigned char *decryptedBytes = (unsigned char*)malloc(encryptedLength);
-	AES_cbc_encrypt([self bytes] + 16, decryptedBytes, encryptedLength, &aesKey, iv, AES_DECRYPT);
+	unsigned char *decryptedBytes = calloc(1,encryptedLength);
+	
+	CCCryptorStatus res = CCCrypt(
+			kCCDecrypt,                          // operation mode
+			kCCAlgorithmAES128,                  // algorithm
+			0,                                   // options. We use our own padding algorithm and CBC is the default
+			[aesKey bytes],                      // key bytes
+			kCCKeySizeAES128,                    // key length
+			iv,                                  // iv bytes (length == block size)
+			([self bytes] + kCCBlockSizeAES128), // raw data
+			encryptedLength,                     // length of raw data
+			decryptedBytes,                      // output buffer. overwriting input is OK
+			encryptedLength,                     // output buffer size
+			NULL                                 // number of bytes written. not relevant here
+	);
+	
+	if(res != kCCSuccess) {
+		@throw [NSException exceptionWithName:SPCommonCryptoExceptionName
+									   reason:[NSString stringWithFormat:@"CCCrypt() failed! (CCCryptorStatus=%d)",res]
+									 userInfo:@{@"cryptorStatus":@(res)}];
+	}
 
 	// If decryption was successful, these blocks will be zeroed
 	if ( *((UInt32*)decryptedBytes + ((encryptedLength / 4) - 4)) ||
@@ -200,8 +226,14 @@ uint32_t LimitUInt32(NSUInteger i);
 	}
 
 	// Get the size of the data from the last 32-bit chunk
-	NSInteger bigIntDataLength = *((UInt32*)decryptedBytes + ((encryptedLength / 4) - 1));
-	NSInteger dataLength = NSSwapBigIntToHost((unsigned int)bigIntDataLength);
+	uint32_t bigIntDataLength = *((UInt32*)decryptedBytes + ((encryptedLength / sizeof(UInt32)) - 1));
+	uint32_t dataLength = NSSwapBigIntToHost(bigIntDataLength);
+	
+	if(dataLength >= (encryptedLength-sizeof(UInt32))) { //this way dataLength can still reach into padding, but we own that memory anyway.
+		@throw [NSException exceptionWithName:NSInternalInconsistencyException
+									   reason:[NSString stringWithFormat:@"dataLength=%u exceeds encryptedLength=%lu! Either the message is incomplete, decrypting resulted in invalid data, or this is a malicious message!",dataLength,encryptedLength]
+									 userInfo:nil];
+	}
 
 	return [NSData dataWithBytesNoCopy:decryptedBytes length:dataLength];
 }
diff --git a/UnitTests/SPDataAdditionsTests.m b/UnitTests/SPDataAdditionsTests.m
index 0ecad9e7..812eb45d 100644
--- a/UnitTests/SPDataAdditionsTests.m
+++ b/UnitTests/SPDataAdditionsTests.m
@@ -38,6 +38,8 @@
 - (void)testSha1Hash;
 - (void)testDataEncryptedWithPassword;
 - (void)testDataEncryptedWithKeyIV;
+- (void)testDataDecryptedWithPassword;
+- (void)testDataDecryptedWithKey;
 
 @end
 
@@ -186,4 +188,97 @@
 	}
 }
 
+- (void)testDataDecryptedWithPassword
+{
+	//see test above
+	NSData *raw = [@"                " dataUsingEncoding:NSASCIIStringEncoding];
+	unsigned char encrypted[] = {
+		0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41,
+		0x42, 0x43, 0x44, 0x45, 0x46, 0xd3, 0x58, 0x30, 0x95, 0x6d, 0x7f,
+		0xf5, 0x1e, 0x18, 0xb0, 0xbc, 0x1f, 0xb3, 0xe4, 0x52, 0xb1, 0x75,
+		0x4c, 0xc3, 0x52, 0xd0, 0x93, 0xad, 0xff, 0x36, 0x4a, 0xae, 0xbe,
+		0x60, 0x32, 0xdd, 0x71, 0xef, 0xce, 0x2e, 0x8b, 0x09, 0xcb, 0x9a,
+		0x44, 0x32, 0xb3, 0xda, 0x42, 0x58, 0x29, 0x78, 0xc3
+	};
+	NSData *encData = [NSData dataWithBytesNoCopy:encrypted length:sizeof(encrypted) freeWhenDone:NO];
+	
+	NSData *decrypted = [encData dataDecryptedWithPassword:@""];
+	
+	STAssertEqualObjects(decrypted, raw, @"Decrypt simple data encrypted with empty password");
+}
+
+- (void)testDataDecryptedWithKey
+{
+	NSData *raw = [@"                " dataUsingEncoding:NSASCIIStringEncoding];
+	
+	unsigned char keyRaw[] = {0xda,0x39,0xa3,0xee,0x5e,0x6b,0x4b,0x0d,0x32,0x55,0xbf,0xef,0x95,0x60,0x18,0x90,0xaf,0xd8,0x07,0x09}; // sha1("")
+	NSData *key = [NSData dataWithBytes:keyRaw length:16];
+	
+	unsigned char encrypted[] = {
+		0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41,
+		0x42, 0x43, 0x44, 0x45, 0x46, 0xd3, 0x58, 0x30, 0x95, 0x6d, 0x7f,
+		0xf5, 0x1e, 0x18, 0xb0, 0xbc, 0x1f, 0xb3, 0xe4, 0x52, 0xb1, 0x75,
+		0x4c, 0xc3, 0x52, 0xd0, 0x93, 0xad, 0xff, 0x36, 0x4a, 0xae, 0xbe,
+		0x60, 0x32, 0xdd, 0x71, 0xef, 0xce, 0x2e, 0x8b, 0x09, 0xcb, 0x9a,
+		0x44, 0x32, 0xb3, 0xda, 0x42, 0x58, 0x29, 0x78, 0xc3
+	};
+	NSData *encData = [NSData dataWithBytesNoCopy:encrypted length:sizeof(encrypted) freeWhenDone:NO];
+	
+	// invalid key length
+	{
+		@try {
+			[encData dataDecryptedWithKey:[NSData data]];
+			STFail(@"Invalid key length!");
+		}
+		@catch (NSException *exception) {
+			//expected
+		}
+	}
+	// data too short for encryption
+	{
+		@try {
+			[[@"Hello World!" dataUsingEncoding:NSASCIIStringEncoding] dataDecryptedWithKey:key];
+			STFail(@"Invalid data length!");
+		}
+		@catch (NSException *exception) {
+			//expected
+		}
+	}
+	// wrong data with valid length
+	{
+		NSData *inp = [@"12345678901234567890123456789012" dataUsingEncoding:NSASCIIStringEncoding];
+		STAssertNil([inp dataDecryptedWithKey:key], @"Trying to decrypt invalid data.");
+	}
+	// wrong data with invalid length
+	{
+		NSData *inp = [@"12345678901234567890123456789012345678901234567" dataUsingEncoding:NSASCIIStringEncoding];
+		STAssertNil([inp dataDecryptedWithKey:key], @"Trying to decrypt data with invalid length.");
+	}
+	// simple decryption test
+	{
+		NSData *decrypted = [encData dataDecryptedWithKey:key];
+		STAssertEqualObjects(decrypted, raw, @"Simple Decryption test");
+	}
+	// malicious message test
+	{
+		//this is an empty message with a length field set to UINT32_MAX
+		unsigned char _encrypted[] = {
+			0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41,
+			0x42, 0x43, 0x44, 0x45, 0x46, 0x50, 0xc9, 0xca, 0x75, 0x14, 0xd3,
+			0x6e, 0xec, 0x9e, 0xc6, 0x4c, 0x25, 0x02, 0x33, 0xdd, 0x86, 0x54,
+			0xea, 0x1a, 0x0d, 0xe9, 0x88, 0xe3, 0xeb, 0xcb, 0xb7, 0x01, 0x52,
+			0x42, 0x1c, 0xd8, 0xd5
+		};
+		NSData *_encData = [NSData dataWithBytesNoCopy:_encrypted length:sizeof(_encrypted) freeWhenDone:NO];
+		
+		@try {
+			[_encData dataDecryptedWithKey:key];
+			STFail(@"Malicious message with invalid data length");
+		}
+		@catch (NSException *exception) {
+			//expected
+		}
+	}
+}
+
 @end
diff --git a/sequel-pro.xcodeproj/project.pbxproj b/sequel-pro.xcodeproj/project.pbxproj
index c2c7e035..0958501d 100644
--- a/sequel-pro.xcodeproj/project.pbxproj
+++ b/sequel-pro.xcodeproj/project.pbxproj
@@ -181,7 +181,8 @@
 		501B1D181728A3DA0017C92E /* SPCharsetCollationHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = 501B1D171728A3DA0017C92E /* SPCharsetCollationHelper.m */; };
 		502D21F61BA50710000D4CE7 /* SPDataAdditionsTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 502D21F51BA50710000D4CE7 /* SPDataAdditionsTests.m */; };
 		502D21F81BA50966000D4CE7 /* SPDataAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = BC2C16D30FEBEDF10003993B /* SPDataAdditions.m */; };
-		502D21FA1BA509AF000D4CE7 /* libcrypto.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = 502D21F91BA509AF000D4CE7 /* libcrypto.dylib */; };
+		502D22151BA62FA5000D4CE7 /* Security.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = B5EAC0FC0EC87FF900CC579C /* Security.framework */; };
+		502D22161BA62FF5000D4CE7 /* Security.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = B5EAC0FC0EC87FF900CC579C /* Security.framework */; };
 		503B02CA1AE82C5E0060CAB1 /* SPTableFilterParser.m in Sources */ = {isa = PBXBuildFile; fileRef = 503B02C91AE82C5E0060CAB1 /* SPTableFilterParser.m */; };
 		503B02CF1AE95C2C0060CAB1 /* SPTableFilterParserTest.m in Sources */ = {isa = PBXBuildFile; fileRef = 503B02CE1AE95C2C0060CAB1 /* SPTableFilterParserTest.m */; };
 		503B02D11AE95DD40060CAB1 /* SPTableFilterParser.m in Sources */ = {isa = PBXBuildFile; fileRef = 503B02C91AE82C5E0060CAB1 /* SPTableFilterParser.m */; };
@@ -409,7 +410,6 @@
 		BC09D7E312A786FB0030DB64 /* cancel.png in Resources */ = {isa = PBXBuildFile; fileRef = BC09D7DD12A786FB0030DB64 /* cancel.png */; };
 		BC0E1486120AAB5600E52E25 /* SPDataAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = BC2C16D30FEBEDF10003993B /* SPDataAdditions.m */; };
 		BC0E1487120AAB5C00E52E25 /* SPStringAdditions.m in Sources */ = {isa = PBXBuildFile; fileRef = 1789343B0F30C1DD0097539A /* SPStringAdditions.m */; };
-		BC0E1493120AABE900E52E25 /* libcrypto.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = 17B7B58F1016028F00F057DE /* libcrypto.dylib */; };
 		BC0E14A1120AAC2E00E52E25 /* libbz2.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = 179ECEC611F265EE009C6A40 /* libbz2.dylib */; };
 		BC0ED3DA12A9196C00088461 /* SPChooseMenuItemDialog.m in Sources */ = {isa = PBXBuildFile; fileRef = BC0ED3D912A9196C00088461 /* SPChooseMenuItemDialog.m */; };
 		BC1847EA0FE6EC8400094BFB /* SPEditSheetTextView.m in Sources */ = {isa = PBXBuildFile; fileRef = BC1847E90FE6EC8400094BFB /* SPEditSheetTextView.m */; };
@@ -758,7 +758,6 @@
 		17A7773711C52E61001E27B4 /* English */ = {isa = PBXFileReference; lastKnownFileType = file.xib; name = English; path = Interfaces/English.lproj/IndexesView.xib; sourceTree = "<group>"; };
 		17AF787911FC41C00073D043 /* SPExportFilenameUtilities.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SPExportFilenameUtilities.h; sourceTree = "<group>"; };
 		17AF787A11FC41C00073D043 /* SPExportFilenameUtilities.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SPExportFilenameUtilities.m; sourceTree = "<group>"; };
-		17B7B58F1016028F00F057DE /* libcrypto.dylib */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.dylib"; name = libcrypto.dylib; path = /usr/lib/libcrypto.dylib; sourceTree = "<absolute>"; };
 		17B7B591101602AE00F057DE /* libssl.dylib */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.dylib"; name = libssl.dylib; path = /usr/lib/libssl.dylib; sourceTree = "<absolute>"; };
 		17BA2A3015275D8600389803 /* SPExportInterfaceController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SPExportInterfaceController.h; sourceTree = "<group>"; };
 		17BA2A3115275D8600389803 /* SPExportInterfaceController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SPExportInterfaceController.m; sourceTree = "<group>"; };
@@ -895,7 +894,6 @@
 		501B1D161728A3DA0017C92E /* SPCharsetCollationHelper.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SPCharsetCollationHelper.h; sourceTree = "<group>"; };
 		501B1D171728A3DA0017C92E /* SPCharsetCollationHelper.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SPCharsetCollationHelper.m; sourceTree = "<group>"; };
 		502D21F51BA50710000D4CE7 /* SPDataAdditionsTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SPDataAdditionsTests.m; sourceTree = "<group>"; };
-		502D21F91BA509AF000D4CE7 /* libcrypto.dylib */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.dylib"; name = libcrypto.dylib; path = usr/lib/libcrypto.dylib; sourceTree = SDKROOT; };
 		5037F79A1B00148000733564 /* SPNamedNode.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SPNamedNode.h; sourceTree = "<group>"; };
 		503B02C81AE82C5E0060CAB1 /* SPTableFilterParser.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SPTableFilterParser.h; sourceTree = "<group>"; };
 		503B02C91AE82C5E0060CAB1 /* SPTableFilterParser.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SPTableFilterParser.m; sourceTree = "<group>"; };
@@ -1277,7 +1275,7 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				502D21FA1BA509AF000D4CE7 /* libcrypto.dylib in Frameworks */,
+				502D22151BA62FA5000D4CE7 /* Security.framework in Frameworks */,
 				1717F9DB1558114D0065C036 /* OCMock.framework in Frameworks */,
 				1717FA43155831600065C036 /* libicucore.dylib in Frameworks */,
 				50EA92671AB23EE1008D3C4F /* SPMySQL.framework in Frameworks */,
@@ -1288,8 +1286,8 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				502D22161BA62FF5000D4CE7 /* Security.framework in Frameworks */,
 				BC0E14A1120AAC2E00E52E25 /* libbz2.dylib in Frameworks */,
-				BC0E1493120AABE900E52E25 /* libcrypto.dylib in Frameworks */,
 				584D87C415141A5D00F24774 /* libz.dylib in Frameworks */,
 				58475686120A065B0057631F /* CoreFoundation.framework in Frameworks */,
 				584756B5120A06740057631F /* CoreServices.framework in Frameworks */,
@@ -1364,7 +1362,6 @@
 				296DC8BE0F9091DF002A3258 /* libicucore.dylib */,
 				179ECEC611F265EE009C6A40 /* libbz2.dylib */,
 				17B7B591101602AE00F057DE /* libssl.dylib */,
-				17B7B58F1016028F00F057DE /* libcrypto.dylib */,
 				584D87BE15141A4A00F24774 /* libz.dylib */,
 			);
 			name = "Linked Frameworks";
@@ -2356,7 +2353,6 @@
 		2A37F4C3FDCFA73011CA2CEA /* Frameworks */ = {
 			isa = PBXGroup;
 			children = (
-				502D21F91BA509AF000D4CE7 /* libcrypto.dylib */,
 				1058C7A6FEA54F5311CA2CBB /* Linked Frameworks */,
 			);
 			name = Frameworks;
@@ -3937,10 +3933,7 @@
 				INSTALL_PATH = "$(HOME)/Applications";
 				LIBRARY_SEARCH_PATHS = "$(SRCROOT)/Frameworks/zlib";
 				MACOSX_DEPLOYMENT_TARGET = 10.6;
-				OTHER_LDFLAGS = (
-					"$(SRCROOT)/Frameworks/zlib/libz.a",
-					"-lcrypto",
-				);
+				OTHER_LDFLAGS = "$(SRCROOT)/Frameworks/zlib/libz.a";
 				PRODUCT_NAME = "Sequel Pro";
 				SEPARATE_STRIP = NO;
 			};
@@ -4140,10 +4133,7 @@
 				INSTALL_PATH = "$(HOME)/Applications";
 				LIBRARY_SEARCH_PATHS = "$(SRCROOT)/Frameworks/zlib";
 				MACOSX_DEPLOYMENT_TARGET = 10.6;
-				OTHER_LDFLAGS = (
-					"$(SRCROOT)/Frameworks/zlib/libz.a",
-					"-lcrypto",
-				);
+				OTHER_LDFLAGS = "$(SRCROOT)/Frameworks/zlib/libz.a";
 				PRODUCT_NAME = "Sequel Pro";
 				SEPARATE_STRIP = NO;
 			};
@@ -4167,10 +4157,7 @@
 				INSTALL_PATH = "$(HOME)/Applications";
 				LIBRARY_SEARCH_PATHS = "$(SRCROOT)/Frameworks/zlib";
 				MACOSX_DEPLOYMENT_TARGET = 10.6;
-				OTHER_LDFLAGS = (
-					"$(SRCROOT)/Frameworks/zlib/libz.a",
-					"-lcrypto",
-				);
+				OTHER_LDFLAGS = "$(SRCROOT)/Frameworks/zlib/libz.a";
 				PRODUCT_NAME = "Sequel Pro";
 				SEPARATE_STRIP = NO;
 			};