CKKSRateLimiterTests.m   [plain text]

/*
* Copyright (c) 2017 Apple Inc. All Rights Reserved.
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*
* 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.
*
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*/

#if OCTAGON

#import <XCTest/XCTest.h>
#import <Foundation/NSKeyedArchiver_Private.h>
#import "keychain/ckks/CKKSOutgoingQueueEntry.h"
#import "keychain/ckks/CKKSRateLimiter.h"

@interface CKKSRateLimiterTests : XCTestCase
- (CKKSOutgoingQueueEntry *)oqe;
@property CKKSRateLimiter *rl;
@property NSDictionary *conf;
@property CKKSOutgoingQueueEntry *oqe;
@property NSDate *date;
@property NSDate *compare;
@end

@implementation CKKSRateLimiterTests

- (void)setUp {
[super setUp];
self.rl = [CKKSRateLimiter new];
self.conf = [self.rl config];
self.oqe = [[CKKSOutgoingQueueEntry alloc] initWithCKKSItem:
[[CKKSItem alloc] initWithUUID:@"123"
parentKeyUUID:@""
zoneID:[[CKRecordZoneID alloc] initWithZoneName:@"testzone" ownerName:CKCurrentUserDefaultName]
encItem:nil
wrappedkey:nil
generationCount:1
encver:0]
action:@""
state:@""
waitUntil:nil
accessGroup:@"defaultgroup"];
}

- (void)tearDown {
[super tearDown];
self.rl = nil;
self.conf = nil;
self.oqe = nil;
}

- (int)get:(NSDictionary *)dict key:(NSString *)key {
id obj = dict[key];
XCTAssertNotNil(obj, "Key %@ is in the dictionary", key);
XCTAssert([obj isKindOfClass:[NSNumber class]], "Value for %@ is an NSNumber (%@)", key, [obj class]);
XCTAssertGreaterThan([obj intValue], 0, "Value for %@ is at least non-zero", key);
return [obj intValue];
}

- (unsigned)getUnsigned:(NSDictionary *)dict key:(NSString *)key {
id obj = dict[key];
XCTAssertNotNil(obj, "Key %@ is in the dictionary", key);
XCTAssert([obj isKindOfClass:[NSNumber class]], "Value for %@ is an NSNumber (%@)", key, [obj class]);
XCTAssertGreaterThan([obj unsignedIntValue], 0, "Value for %@ is at least non-zero", key);
return [obj unsignedIntValue];
}

- (void)testConfig {
[self get:[self.rl config] key:@"rateAll"];
[self get:[self.rl config] key:@"rateGroup"];
[self get:[self.rl config] key:@"rateUUID"];
[self get:[self.rl config] key:@"capacityAll"];
[self get:[self.rl config] key:@"capacityGroup"];
[self get:[self.rl config] key:@"capacityUUID"];
[self get:[self.rl config] key:@"trimSize"];
[self get:[self.rl config] key:@"trimTime"];
}

- (void)testBasics {
NSDate *date = [NSDate date];
NSDate *limit = nil;

XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "judge single item");
XCTAssertNil(limit, "NSDate argument nil for zero result");
XCTAssertEqual([self.rl stateSize], 3UL, "RL contains three nodes after single judgment");
[self.rl reset];
XCTAssertEqual([self.rl stateSize], 0UL, "RL is empty after reset");
}

- (void)testAll {
NSDate *date = [NSDate date];
NSDate *limit = nil;
int capacityAll = [self get:[self.rl config] key:@"capacityAll"];
int rateAll = [self get:[self.rl config] key:@"rateAll"];

for (int idx = 0; idx < capacityAll; ++idx) {
self.oqe.accessgroup = [NSString stringWithFormat:@"%d", idx];
self.oqe.uuid = [NSString stringWithFormat:@"%d", idx];
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Repeat (%d) All succeeds, limit %d", idx, capacityAll);
XCTAssertNil(limit, "Time nil while under All limit");
}

self.oqe.accessgroup = @"Ga";
self.oqe.uuid = @"Ua";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 1, "Repeat All implies congestion");
int delta = [limit timeIntervalSinceDate:date];
XCTAssert(delta > 0 && delta <= rateAll, "send-OK at most one All token into the future");
self.oqe.accessgroup = @"Gb";
self.oqe.uuid = @"Ub";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 1, "Repeat All, still congested");
delta = [limit timeIntervalSinceDate:date];
XCTAssert(delta > rateAll && delta <= (2 * rateAll), "send-OK between one and two All tokens into the future");

self.oqe.accessgroup = @"Gc";
self.oqe.uuid = @"Uc";
date = [limit dateByAddingTimeInterval:rateAll];
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Repeat All is fine after waiting");
XCTAssertEqual([self.rl stateSize], (unsigned long)(2 * (capacityAll + 3) + 1), "state size is %d", 2 * (capacityAll + 3) + 1);
}

- (void)testGroup {
NSDate *date = [NSDate date];
NSDate *limit = nil;
int capacityGroup = [self get:[self.rl config] key:@"capacityGroup"];
int rateGroup = [self get:[self.rl config] key:@"rateGroup"];

for (int idx = 0; idx < capacityGroup; ++idx) {
self.oqe.uuid = [NSString stringWithFormat:@"%d",idx];
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Repeat (%d) Group succeeds, limit %d", idx, capacityGroup);
XCTAssertNil(limit, "sendTime nil while under Group limit");
}

self.oqe.uuid = @"a";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 2, "Repeat Group entry not good");
int delta = [limit timeIntervalSinceDate:date];
XCTAssert(delta > 0 && delta <= rateGroup, "send-OK at most one Group token into the future");

self.oqe.uuid = @"b";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 3, "Repeat Group entry still not good");
delta = [limit timeIntervalSinceDate:date];
XCTAssert(delta > rateGroup && delta <= (2 * rateGroup), "send-OK between one and two Group tokens into the future");
self.oqe.uuid = @"c";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 3, "Repeat Group entry extra bad after not quitting");
delta = [limit timeIntervalSinceDate:date];
XCTAssert(delta > (2 * rateGroup) && delta <= (3 * rateGroup), "send-OK between two and three Group tokens into the future");

self.oqe.uuid = @"d";
date = [limit dateByAddingTimeInterval:rateGroup];
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Repeat Group is fine after waiting");
XCTAssertEqual([self.rl stateSize], (unsigned long)(capacityGroup + 6), "State size is %d", capacityGroup + 6);

}

- (void)testUUID {
NSDate *date = [NSDate date];
NSDate *limit = nil;
int capacityUUID = [self get:[self.rl config] key:@"capacityUUID"];
int rateUUID = [self get:[self.rl config] key:@"rateUUID"];

for (int idx = 0; idx < capacityUUID; ++idx) {
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Repeat (%d) UUID succeeds, limit %d", idx, capacityUUID);
XCTAssertNil(limit, "Time unmodified while under UUID limit");
}

XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 4, "Repeat UUID over limit is bad behavior");
int delta = [limit timeIntervalSinceDate:date];
XCTAssert(delta > 0 && delta <= rateUUID, "Received send-OK at most one UUID token into the future");
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 4, "Repeat over-limit UUID is bad behavior");
delta = [limit timeIntervalSinceDate:date];
XCTAssert(delta > rateUUID && delta <= (2 * rateUUID), "send-OK between one and two UUID tokens into the future");

// test UUID success after borrow
date = [limit dateByAddingTimeInterval:rateUUID];
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Repeat UUID is fine after waiting");
XCTAssertEqual([self.rl stateSize], 3UL, "state size is 3");

}

- (void)testTrimTime {
NSDate *date = [NSDate date];
NSDate *limit = nil;
int trimTime = [self get:[self.rl config] key:@"trimTime"];
int capacityAll = [self get:[self.rl config] key:@"capacityAll"];

for (int idx = 0; idx < capacityAll; ++idx) {
self.oqe.accessgroup = [NSString stringWithFormat:@"%d", idx];
self.oqe.uuid = [NSString stringWithFormat:@"%d", idx];
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Repeat (%d) All succeeds, limit %d", idx, capacityAll);
XCTAssertNil(limit, "Time nil while under All limit");
}

XCTAssertEqual([self.rl stateSize], (unsigned long)(2 * capacityAll + 1), "state size is %d", 2 * capacityAll + 1);

date = [date dateByAddingTimeInterval:trimTime + 1];
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Entry addition succeeds after long silence");
XCTAssertEqual([self.rl stateSize], 3UL, "Trim has wiped out all buckets except from call immediately before");
}

- (void)testTrimSize {
NSDate *date = [NSDate date];
NSDate *limit = nil;
NSDate *compare = [date copy];
int trimSize = [self get:[self.rl config] key:@"trimSize"];
int trimTime = [self get:[self.rl config] key:@"trimTime"];
int rateAll = [self get:[self.rl config] key:@"rateAll"];

self.oqe.accessgroup = @"a";
self.oqe.uuid = @"a";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 0, "Adding single item, no problem");

// Cannot fill state completely due to repeated judgements, it'll trigger overload otherwise
for (int idx = 0; [self.rl stateSize] < (unsigned long)(trimSize - 2); ++idx) {
self.oqe.accessgroup = [NSString stringWithFormat:@"%d", idx];
self.oqe.uuid = [NSString stringWithFormat:@"%d", idx];
for (int i = 0; i < rateAll; ++i) {
XCTAssertLessThan([self.rl judge:self.oqe at:date limitTime:&limit], 5, "Adding items and hitting their dates");
date = [compare copy];
}
}

unsigned long statesize = [self.rl stateSize];

self.oqe.accessgroup = @"b";
self.oqe.uuid = @"b";
XCTAssertLessThan([self.rl judge:self.oqe at:date limitTime:&limit], 5, "Top off state");

date = [compare dateByAddingTimeInterval:trimTime];

XCTAssertLessThan([self.rl judge:self.oqe at:date limitTime:&limit], 5, "New entry after at least one has expired fits");
XCTAssertEqual([self.rl stateSize], statesize, "Item 'a' was trimmed and 'b' got added");
}

- (void)testOverload {
NSDate *date = [NSDate date];
NSDate *limit = nil;
int trimSize = [self get:[self.rl config] key:@"trimSize"];
//int rateAll = [self get:[self.rl config] key:@"rateAll"];;
unsigned overloadDuration = [self getUnsigned:[self.rl config] key:@"overloadDuration"];;

for (int idx = 0; idx < (trimSize / 2); ++idx) {
self.oqe.accessgroup = [NSString stringWithFormat:@"%d", idx];
self.oqe.uuid = [NSString stringWithFormat:@"%d", idx];
XCTAssertLessThan([self.rl judge:self.oqe at:date limitTime:&limit], 5, "No overload triggered yet ramming data into RL");
}

NSDate *preOverload = [limit copy];
self.oqe.accessgroup = @"a";
self.oqe.uuid = @"a";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 5, "Triggered overload");
NSDate *postOverload = [preOverload dateByAddingTimeInterval:overloadDuration];
// NSDates are doubles so we add a little rounding error leeway
XCTAssertEqualWithAccuracy(limit.timeIntervalSinceReferenceDate, postOverload.timeIntervalSinceReferenceDate, 1, "Got expected overload duration");

unsigned long statesize = [self.rl stateSize];

self.oqe.accessgroup = @"b";
self.oqe.uuid = @"b";
XCTAssertEqual([self.rl judge:self.oqe at:date limitTime:&limit], 5, "Overload");
XCTAssertEqual(statesize, [self.rl stateSize], "No items added during overload");

XCTAssertEqual([self.rl judge:self.oqe at:limit limitTime:&limit], 0, "Judgment succeeds post-overload");
}

- (void)testEncoding {
NSDate* date = [NSDate date];
NSDate* limit = nil;
[self.rl judge:self.oqe at:date limitTime:&limit];

NSKeyedArchiver* encoder = [[NSKeyedArchiver alloc] initRequiringSecureCoding:YES];
[encoder encodeObject: self.rl forKey:@"unneeded"];
NSData* data = encoder.encodedData;
XCTAssertNotNil(data, "Still have our data object");
XCTAssertTrue(data.length > 0u, "Encoder produced some data");

NSKeyedUnarchiver* decoder = [[NSKeyedUnarchiver alloc] initForReadingFromData: data error:nil];
CKKSRateLimiter* rl = [decoder decodeObjectOfClass: [CKKSRateLimiter class] forKey:@"unneeded"];
XCTAssertNotNil(rl, "Decoded data into a CKKSRateLimiter");

XCTAssertEqualObjects(self.rl, rl, "RateLimiter objects are equal after encoding/decoding");
}

@end

#endif //OCTAGON