CKKSSQLDatabaseObject.m   [plain text]

/*
* Copyright (c) 2016 Apple Inc. All Rights Reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this
* file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/

#import <Foundation/Foundation.h>
#import "CKKSSQLDatabaseObject.h"
#include "keychain/securityd/SecItemServer.h"

#import "keychain/ckks/CKKS.h"
#import "CKKSKeychainView.h"

@interface CKKSSQLResult ()
@property (nullable) NSString* stringValue;
@end

@implementation CKKSSQLResult
- (instancetype)init:(NSString* _Nullable)value
{
if((self = [super init])) {
_stringValue = value;
}
return self;
}

- (BOOL)asBOOL
{
return [self.stringValue boolValue];
}

- (NSInteger)asNSInteger
{
return [self.stringValue integerValue];
}

- (NSString* _Nullable)asString
{
return self.stringValue;
}

- (NSNumber* _Nullable)asNSNumberInteger
{
if(self.stringValue == nil) {
return nil;
}
return [NSNumber numberWithInteger: [self.stringValue integerValue]];
}

- (NSDate* _Nullable)asISO8601Date
{
if(self.stringValue == nil) {
return nil;
}

NSISO8601DateFormatter* dateFormat = [[NSISO8601DateFormatter alloc] init];
return [dateFormat dateFromString:self.stringValue];
}

- (NSData* _Nullable)asBase64DecodedData
{
if(self.stringValue == nil) {
return nil;
}
return [[NSData alloc] initWithBase64EncodedString:self.stringValue options:0];
}
@end

@implementation CKKSSQLDatabaseObject

+ (bool) saveToDatabaseTable: (NSString*) table row: (NSDictionary*) row connection: (SecDbConnectionRef) dbconn error: (NSError * __autoreleasing *) error {
__block CFErrorRef cferror = NULL;

bool (^doWithConnection)(SecDbConnectionRef) = ^bool (SecDbConnectionRef dbconn) {
NSString * columns = [row.allKeys componentsJoinedByString:@", "];
NSMutableString * values = [[NSMutableString alloc] init];
for(NSUInteger i = 0; i < [row.allKeys count]; i++) {
if(i != 0) {
[values appendString: @",?"];
} else {
[values appendString: @"?"];
}
}

NSString *sql = [[NSString alloc] initWithFormat: @"INSERT OR REPLACE into %@ (%@) VALUES (%@);", table, columns, values];

SecDbPrepare(dbconn, (__bridge CFStringRef) sql, &cferror, ^void (sqlite3_stmt *stmt) {
[row.allKeys enumerateObjectsUsingBlock:^(id _Nonnull key, NSUInteger i, BOOL * _Nonnull stop) {
SecDbBindObject(stmt, (int)(i+1), (__bridge CFStringRef) row[key], &cferror);
}];

SecDbStep(dbconn, stmt, &cferror, ^(bool *stop) {
// don't do anything, I guess?
});
});

return true;
};

if(dbconn) {
doWithConnection(dbconn);
} else {
kc_with_dbt(true, &cferror, doWithConnection);
}

bool ret = cferror == NULL;

SecTranslateError(error, cferror);

return ret;
}

+ (NSString*) makeWhereClause: (NSDictionary*) whereDict {
if(!whereDict) {
return @"";
}
NSMutableString * whereClause = [[NSMutableString alloc] init];
__block bool conjunction = false;
[whereDict enumerateKeysAndObjectsUsingBlock: ^(NSString* key, NSNumber* value, BOOL* stop) {
if(!conjunction) {
[whereClause appendFormat: @" WHERE "];
} else {
[whereClause appendFormat: @" AND "];
}

if([value class] == [CKKSSQLWhereObject class]) {
// Use this string verbatim
CKKSSQLWhereObject* whereob = (CKKSSQLWhereObject*) value;
[whereClause appendFormat: @"%@%@%@", key, whereob.sqlOp, whereob.contents];
} else {
[whereClause appendFormat: @"%@=(?)", key];
}

conjunction = true;
}];
return whereClause;
}

+ (NSString*) groupByClause: (NSArray*) columns {
if(!columns) {
return @"";
}
NSMutableString * groupByClause = [[NSMutableString alloc] init];
__block bool conjunction = false;
[columns enumerateObjectsUsingBlock: ^(NSString* column, NSUInteger i, BOOL* stop) {
if(!conjunction) {
[groupByClause appendFormat: @" GROUP BY "];
} else {
[groupByClause appendFormat: @", "];
}

[groupByClause appendFormat: @"%@", column];

conjunction = true;
}];
return groupByClause;
}

+ (NSString*)orderByClause: (NSArray*) columns {
if(!columns || columns.count == 0u) {
return @"";
}
NSMutableString * orderByClause = [[NSMutableString alloc] init];
__block bool conjunction = false;
[columns enumerateObjectsUsingBlock: ^(NSString* column, NSUInteger i, BOOL* stop) {
if(!conjunction) {
[orderByClause appendFormat: @" ORDER BY "];
} else {
[orderByClause appendFormat: @", "];
}

[orderByClause appendFormat: @"%@", column];

conjunction = true;
}];
return orderByClause;
}

+ (bool) deleteFromTable: (NSString*) table where: (NSDictionary*) whereDict connection:(SecDbConnectionRef) dbconn error: (NSError * __autoreleasing *) error {
__block CFErrorRef cferror = NULL;

bool (^doWithConnection)(SecDbConnectionRef) = ^bool (SecDbConnectionRef dbconn) {
NSString* whereClause = [CKKSSQLDatabaseObject makeWhereClause: whereDict];

NSString * sql = [[NSString alloc] initWithFormat: @"DELETE FROM %@%@;", table, whereClause];
SecDbPrepare(dbconn, (__bridge CFStringRef) sql, &cferror, ^void (sqlite3_stmt *stmt) {
__block int whereObjectsSkipped = 0;

[whereDict.allKeys enumerateObjectsUsingBlock:^(id _Nonnull key, NSUInteger i, BOOL * _Nonnull stop) {
if([whereDict[key] class] != [CKKSSQLWhereObject class]) {
SecDbBindObject(stmt, (int)(i+1-whereObjectsSkipped), (__bridge CFStringRef) whereDict[key], &cferror);
} else {
whereObjectsSkipped += 1;
}
}];

SecDbStep(dbconn, stmt, &cferror, ^(bool *stop) {
});
});
return true;
};

if(dbconn) {
doWithConnection(dbconn);
} else {
kc_with_dbt(true, &cferror, doWithConnection);
}

// Deletes finish in a single step, so if we didn't get an error, the delete 'happened'
bool status = (cferror == nil);

if(error) {
*error = (NSError*) CFBridgingRelease(cferror);
} else {
CFReleaseNull(cferror);
}

return status;
}

+ (bool)queryDatabaseTable:(NSString*)table
where:(NSDictionary*)whereDict
columns:(NSArray*)names
groupBy:(NSArray*)groupColumns
orderBy:(NSArray*)orderColumns
limit:(ssize_t)limit
processRow:(void (^)(NSDictionary<NSString*, CKKSSQLResult*>*)) processRow
error:(NSError * __autoreleasing *) error {
__block CFErrorRef cferror = NULL;

kc_with_dbt(true, &cferror, ^bool (SecDbConnectionRef dbconn) {
NSString * columns = [names componentsJoinedByString:@", "];
NSString * whereClause = [CKKSSQLDatabaseObject makeWhereClause: whereDict];
NSString * groupByClause = [CKKSSQLDatabaseObject groupByClause: groupColumns];
NSString * orderByClause = [CKKSSQLDatabaseObject orderByClause: orderColumns];
NSString * limitClause = (limit > 0 ? [NSString stringWithFormat:@" LIMIT %lu", limit] : @"");

NSString * sql = [[NSString alloc] initWithFormat: @"SELECT %@ FROM %@%@%@%@%@;", columns, table, whereClause, groupByClause, orderByClause, limitClause];
SecDbPrepare(dbconn, (__bridge CFStringRef) sql, &cferror, ^void (sqlite3_stmt *stmt) {
__block int whereObjectsSkipped = 0;
[whereDict.allKeys enumerateObjectsUsingBlock:^(id _Nonnull key, NSUInteger i, BOOL * _Nonnull stop) {
if([whereDict[key] class] != [CKKSSQLWhereObject class]) {
SecDbBindObject(stmt, (int)(i+1-whereObjectsSkipped), (__bridge CFStringRef) whereDict[key], &cferror);
} else {
whereObjectsSkipped += 1;
}
}];

SecDbStep(dbconn, stmt, &cferror, ^(bool *stop) {
__block NSMutableDictionary<NSString*, CKKSSQLResult*>* row = [[NSMutableDictionary alloc] init];

[names enumerateObjectsUsingBlock:^(id _Nonnull name, NSUInteger i, BOOL * _Nonnull stop) {
const char * col = (const char *) sqlite3_column_text(stmt, (int)i);
row[name] = [[CKKSSQLResult alloc] init:col ? [NSString stringWithUTF8String:col] : nil];
}];

processRow(row);
});
});
return true;
});

bool ret = (cferror == NULL);
SecTranslateError(error, cferror);
return ret;
}

+ (NSString *)quotedString:(NSString *)string
{
char *quotedMaxField = sqlite3_mprintf("%q", [string UTF8String]);
if (quotedMaxField == NULL) {
abort();
}
NSString *rstring = [NSString stringWithUTF8String:quotedMaxField];
sqlite3_free(quotedMaxField);
return rstring;
}

+ (bool)queryMaxValueForField:(NSString*)maxField
inTable:(NSString*)table
where:(NSDictionary*)whereDict
columns:(NSArray*)names
processRow:(void (^)(NSDictionary<NSString*, CKKSSQLResult*>*))processRow
{
__block CFErrorRef cferror = NULL;

kc_with_dbt(false, &cferror, ^bool(SecDbConnectionRef dbconn) {
NSString *quotedMaxField = [self quotedString:maxField];
NSString *quotedTable = [self quotedString:table];

NSMutableArray<NSString *>* quotedNames = [NSMutableArray array];
for (NSString *element in names) {
[quotedNames addObject:[self quotedString:element]];
}

NSString* columns = [[quotedNames componentsJoinedByString:@", "] stringByAppendingFormat:@", %@", quotedMaxField];
NSString* whereClause = [CKKSSQLDatabaseObject makeWhereClause:whereDict];

NSString* sql = [[NSString alloc] initWithFormat:@"SELECT %@ FROM %@%@", columns, quotedTable, whereClause];
SecDbPrepare(dbconn, (__bridge CFStringRef)sql, &cferror, ^(sqlite3_stmt* stmt) {
[whereDict.allKeys enumerateObjectsUsingBlock:^(id _Nonnull key, NSUInteger i, BOOL* _Nonnull stop) {
if ([whereDict[key] class] != [CKKSSQLWhereObject class]) {
SecDbBindObject(stmt, (int)(i+1), (__bridge CFStringRef) whereDict[key], &cferror);
}
}];

SecDbStep(dbconn, stmt, &cferror, ^(bool*stop) {
__block NSMutableDictionary<NSString*, CKKSSQLResult*>* row = [[NSMutableDictionary alloc] init];

[names enumerateObjectsUsingBlock:^(id _Nonnull name, NSUInteger i, BOOL * _Nonnull stop) {
const char * col = (const char *) sqlite3_column_text(stmt, (int)i);
row[name] = [[CKKSSQLResult alloc] init:col ? [NSString stringWithUTF8String:col] : nil];
}];

processRow(row);
});
});

return true;
});

bool ret = (cferror == NULL);
return ret;
}

#pragma mark - Instance methods

- (bool) saveToDatabase: (NSError * __autoreleasing *) error {
return [self saveToDatabaseWithConnection:nil error: error];
}

- (bool) saveToDatabaseWithConnection: (SecDbConnectionRef) conn error: (NSError * __autoreleasing *) error {
// Todo: turn this into a transaction

NSDictionary* currentWhereClause = [self whereClauseToFindSelf];

// First, if we were loaded from the database and the where clause has changed, delete the old record.
if(self.originalSelfWhereClause && ![self.originalSelfWhereClause isEqualToDictionary: currentWhereClause]) {
secdebug("ckkssql", "Primary key changed; removing old row at %@", self.originalSelfWhereClause);
if(![CKKSSQLDatabaseObject deleteFromTable:[[self class] sqlTable] where: self.originalSelfWhereClause connection:conn error: error]) {
return false;
}
}

bool ok = [CKKSSQLDatabaseObject saveToDatabaseTable: [[self class] sqlTable]
row: [self sqlValues]
connection: conn
error: error];

if(ok) {
secdebug("ckkssql", "Saved %@", self);
} else {
secdebug("ckkssql", "Couldn't save %@: %@", self, error ? *error : @"unknown");
}
return ok;
}

- (bool) deleteFromDatabase: (NSError * __autoreleasing *) error {
bool ok = [CKKSSQLDatabaseObject deleteFromTable:[[self class] sqlTable] where: [self whereClauseToFindSelf] connection:nil error: error];

if(ok) {
secdebug("ckkssql", "Deleted %@", self);
} else {
secdebug("ckkssql", "Couldn't delete %@: %@", self, error ? *error : @"unknown");
}
return ok;
}

+ (bool) deleteAll: (NSError * __autoreleasing *) error {
bool ok = [CKKSSQLDatabaseObject deleteFromTable:[self sqlTable] where: nil connection:nil error: error];

if(ok) {
secdebug("ckkssql", "Deleted all %@", self);
} else {
secdebug("ckkssql", "Couldn't delete all %@: %@", self, error ? *error : @"unknown");
}
return ok;
}

+ (instancetype) fromDatabaseWhere: (NSDictionary*) whereDict error: (NSError * __autoreleasing *) error {
id ret = [self tryFromDatabaseWhere: whereDict error:error];

if(!ret && error) {
*error = [NSError errorWithDomain:@"securityd"
code:errSecItemNotFound
userInfo:@{NSLocalizedDescriptionKey:
[NSString stringWithFormat: @"%@ does not exist in database where %@", [self class], whereDict]}];
}

return ret;
}

+ (instancetype _Nullable) tryFromDatabaseWhere: (NSDictionary*) whereDict error: (NSError * __autoreleasing *) error {
__block id ret = nil;

[CKKSSQLDatabaseObject queryDatabaseTable: [self sqlTable]
where: whereDict
columns: [self sqlColumns]
groupBy: nil
orderBy:nil
limit: -1
processRow: ^(NSDictionary<NSString*, CKKSSQLResult*>* row) {
ret = [[self fromDatabaseRow: row] memoizeOriginalSelfWhereClause];
}
error: error];

return ret;
}

+ (NSArray*) all: (NSError * __autoreleasing *) error {
return [self allWhere: nil error:error];
}

+ (NSArray*) allWhere: (NSDictionary*) whereDict error: (NSError * __autoreleasing *) error {
__block NSMutableArray* items = [[NSMutableArray alloc] init];

[CKKSSQLDatabaseObject queryDatabaseTable: [self sqlTable]
where: whereDict
columns: [self sqlColumns]
groupBy: nil
orderBy:nil
limit: -1
processRow: ^(NSDictionary<NSString*, CKKSSQLResult*>* row) {
[items addObject: [[self fromDatabaseRow: row] memoizeOriginalSelfWhereClause]];
}
error: error];

return items;
}

+ (NSArray*)fetch: (size_t)count error: (NSError * __autoreleasing *) error {
return [self fetch: count where:nil orderBy:nil error:error];
}

+ (NSArray*)fetch: (size_t)count where:(NSDictionary*)whereDict error: (NSError * __autoreleasing *) error {
return [self fetch: count where:whereDict orderBy:nil error:error];
}

+ (NSArray*)fetch:(size_t)count
where:(NSDictionary*)whereDict
orderBy:(NSArray*) orderColumns
error:(NSError * __autoreleasing *) error {
__block NSMutableArray* items = [[NSMutableArray alloc] init];

[CKKSSQLDatabaseObject queryDatabaseTable: [self sqlTable]
where: whereDict
columns: [self sqlColumns]
groupBy:nil
orderBy:orderColumns
limit: (ssize_t) count
processRow: ^(NSDictionary<NSString*, CKKSSQLResult*>* row) {
[items addObject: [[self fromDatabaseRow: row] memoizeOriginalSelfWhereClause]];
}
error: error];

return items;
}

- (instancetype) memoizeOriginalSelfWhereClause {
_originalSelfWhereClause = [self whereClauseToFindSelf];
return self;
}

#pragma mark - Subclass methods

+ (instancetype)fromDatabaseRow:(NSDictionary<NSString *, CKKSSQLResult*>*)row {
@throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:@"A subclass must override %@", NSStringFromSelector(_cmd)]
userInfo:nil];
}

+ (NSString*) sqlTable {
@throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:@"A subclass must override %@", NSStringFromSelector(_cmd)]
userInfo:nil];
}

+ (NSArray<NSString*>*) sqlColumns {
@throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:@"A subclass must override %@", NSStringFromSelector(_cmd)]
userInfo:nil];
}

- (NSDictionary<NSString*,NSString*>*) sqlValues {
@throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:@"A subclass must override %@", NSStringFromSelector(_cmd)]
userInfo:nil];
}

- (NSDictionary<NSString*,NSString*>*) whereClauseToFindSelf {
@throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:@"A subclass must override %@", NSStringFromSelector(_cmd)]
userInfo:nil];
}

- (instancetype)copyWithZone:(NSZone *)zone {
CKKSSQLDatabaseObject *dbCopy = [[[self class] allocWithZone:zone] init];
dbCopy->_originalSelfWhereClause = _originalSelfWhereClause;
return dbCopy;
}
@end

#pragma mark - CKKSSQLWhereObject

@implementation CKKSSQLWhereObject
- (instancetype)initWithOperation:(NSString*)op string: (NSString*) str {
if(self = [super init]) {
_sqlOp = op;
_contents = str;
}
return self;
}

+ (instancetype)op:(NSString*) op string: (NSString*) str {
return [[CKKSSQLWhereObject alloc] initWithOperation:op string: str];
}

+ (instancetype)op:(NSString*) op stringValue: (NSString*) str {
return [[CKKSSQLWhereObject alloc] initWithOperation:op string:[NSString stringWithFormat:@"'%@'", str]];
}

@end