[feature] domain block wildcarding (#1178)

* for domain block lookups, lookup along subdomain parts

Signed-off-by: kim <grufwub@gmail.com>

* only lookup up to a max of 5 domain parts to prevent DOS, limit inserted domains to max of 5 subdomains

Signed-off-by: kim <grufwub@gmail.com>

* add test for domain block wildcarding

Signed-off-by: kim <grufwub@gmail.com>

* check cached status first, increase cached domain time

Signed-off-by: kim <grufwub@gmail.com>

* fix domain wildcard part building logic

Signed-off-by: kim <grufwub@gmail.com>

* create separate domain.BlockCache{} type to hold all domain blocks in memory

Signed-off-by: kim <grufwub@gmail.com>

* remove unused variable

Signed-off-by: kim <grufwub@gmail.com>

* add docs and test to domain block cache, check for domain == host in domain block getter funcs

Signed-off-by: kim <grufwub@gmail.com>

* add license text

Signed-off-by: kim <grufwub@gmail.com>

* check order in which we check primary cache

Signed-off-by: kim <grufwub@gmail.com>

* add better documentation of how domain block checking is performed

Signed-off-by: kim <grufwub@gmail.com>

* change

Signed-off-by: kim <grufwub@gmail.com>

Signed-off-by: kim <grufwub@gmail.com>
This commit is contained in:
kim 2022-12-14 09:55:36 +00:00 committed by GitHub
parent 8703933df4
commit 69dd5fed2c
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5 changed files with 350 additions and 39 deletions

170
internal/cache/domain/domain.go vendored Normal file
View file

@ -0,0 +1,170 @@
/*
GoToSocial
Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package domain
import (
"fmt"
"time"
"codeberg.org/gruf/go-cache/v3/ttl"
"github.com/miekg/dns"
)
// BlockCache provides a means of caching domain blocks in memory to reduce load
// on an underlying storage mechanism, e.g. a database.
//
// It consists of a TTL primary cache that stores calculated domain string to block results,
// that on cache miss is filled by calculating block status by iterating over a list of all of
// the domain blocks stored in memory. This reduces CPU usage required by not need needing to
// iterate through a possible 100-1000s long block list, while saving memory by having a primary
// cache of limited size that evicts stale entries. The raw list of all domain blocks should in
// most cases be negligible when it comes to memory usage.
//
// The in-memory block list is kept up-to-date by means of a passed loader function during every
// call to .IsBlocked(). In the case of a nil internal block list, the loader function is called to
// hydrate the cache with the latest list of domain blocks. The .Clear() function can be used to invalidate
// the cache, e.g. when a domain block is added / deleted from the database. It will drop the current
// list of domain blocks and clear all entries from the primary cache.
type BlockCache struct {
pcache *ttl.Cache[string, bool] // primary cache of domains -> block results
blocks []block // raw list of all domain blocks, nil => not loaded.
}
// New returns a new initialized BlockCache instance with given primary cache capacity and TTL.
func New(pcap int, pttl time.Duration) *BlockCache {
c := new(BlockCache)
c.pcache = new(ttl.Cache[string, bool])
c.pcache.Init(0, pcap, pttl)
return c
}
// Start will start the cache background eviction routine with given sweep frequency. If already running or a freq <= 0 provided, this is a no-op. This will block until the eviction routine has started.
func (b *BlockCache) Start(pfreq time.Duration) bool {
return b.pcache.Start(pfreq)
}
// Stop will stop cache background eviction routine. If not running this is a no-op. This will block until the eviction routine has stopped.
func (b *BlockCache) Stop() bool {
return b.pcache.Stop()
}
// IsBlocked checks whether domain is blocked. If the cache is not currently loaded, then the provided load function is used to hydrate it.
// NOTE: be VERY careful using any kind of locking mechanism within the load function, as this itself is ran within the cache mutex lock.
func (b *BlockCache) IsBlocked(domain string, load func() ([]string, error)) (bool, error) {
var blocked bool
// Acquire cache lock
b.pcache.Lock()
defer b.pcache.Unlock()
// Check primary cache for result
entry, ok := b.pcache.Cache.Get(domain)
if ok {
return entry.Value, nil
}
if b.blocks == nil {
// Cache is not hydrated
//
// Load domains from callback
domains, err := load()
if err != nil {
return false, fmt.Errorf("error reloading cache: %w", err)
}
// Drop all domain blocks and recreate
b.blocks = make([]block, len(domains))
for i, domain := range domains {
// Store pre-split labels for each domain block
b.blocks[i].labels = dns.SplitDomainName(domain)
}
}
// Split domain into it separate labels
labels := dns.SplitDomainName(domain)
// Compare this to our stored blocks
for _, block := range b.blocks {
if block.Blocks(labels) {
blocked = true
break
}
}
// Store block result in primary cache
b.pcache.Cache.Set(domain, &ttl.Entry[string, bool]{
Key: domain,
Value: blocked,
Expiry: time.Now().Add(b.pcache.TTL),
})
return blocked, nil
}
// Clear will drop the currently loaded domain list, and clear the primary cache.
// This will trigger a reload on next call to .IsBlocked().
func (b *BlockCache) Clear() {
// Drop all blocks.
b.pcache.Lock()
b.blocks = nil
b.pcache.Unlock()
// Clear needs to be done _outside_ of
// lock, as also acquires a mutex lock.
b.pcache.Clear()
}
// block represents a domain block, and stores the
// deconstructed labels of a singular domain block.
// e.g. []string{"gts", "superseriousbusiness", "org"}.
type block struct {
labels []string
}
// Blocks checks whether the separated domain labels of an
// incoming domain matches the stored (receiving struct) block.
func (b block) Blocks(labels []string) bool {
// Calculate length difference
d := len(labels) - len(b.labels)
if d < 0 {
return false
}
// Iterate backwards through domain block's
// labels, omparing against the incoming domain's.
//
// So for the following input:
// labels = []string{"mail", "google", "com"}
// b.labels = []string{"google", "com"}
//
// These would be matched in reverse order along
// the entirety of the block object's labels:
// "com" => match
// "google" => match
//
// And so would reach the end and return true.
for i := len(b.labels) - 1; i >= 0; i-- {
if b.labels[i] != labels[i+d] {
return false
}
}
return true
}

85
internal/cache/domain/domain_test.go vendored Normal file
View file

@ -0,0 +1,85 @@
/*
GoToSocial
Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package domain_test
import (
"errors"
"testing"
"time"
"github.com/superseriousbusiness/gotosocial/internal/cache/domain"
)
func TestBlockCache(t *testing.T) {
c := domain.New(100, time.Second)
blocks := []string{
"google.com",
"google.co.uk",
"pleroma.bad.host",
}
loader := func() ([]string, error) {
t.Log("load: returning blocked domains")
return blocks, nil
}
// Check a list of known blocked domains.
for _, domain := range []string{
"google.com",
"mail.google.com",
"google.co.uk",
"mail.google.co.uk",
"pleroma.bad.host",
"dev.pleroma.bad.host",
} {
t.Logf("checking domain is blocked: %s", domain)
if b, _ := c.IsBlocked(domain, loader); !b {
t.Errorf("domain should be blocked: %s", domain)
}
}
// Check a list of known unblocked domains.
for _, domain := range []string{
"askjeeves.com",
"ask-kim.co.uk",
"google.ie",
"mail.google.ie",
"gts.bad.host",
"mastodon.bad.host",
} {
t.Logf("checking domain isn't blocked: %s", domain)
if b, _ := c.IsBlocked(domain, loader); b {
t.Errorf("domain should not be blocked: %s", domain)
}
}
// Clear the cache
c.Clear()
knownErr := errors.New("known error")
// Check that reload is actually performed and returns our error
if _, err := c.IsBlocked("", func() ([]string, error) {
t.Log("load: returning known error")
return nil, knownErr
}); !errors.Is(err, knownErr) {
t.Errorf("is blocked did not return expected error: %v", err)
}
}

21
internal/cache/gts.go vendored
View file

@ -20,6 +20,7 @@ package cache
import ( import (
"codeberg.org/gruf/go-cache/v3/result" "codeberg.org/gruf/go-cache/v3/result"
"github.com/superseriousbusiness/gotosocial/internal/cache/domain"
"github.com/superseriousbusiness/gotosocial/internal/config" "github.com/superseriousbusiness/gotosocial/internal/config"
"github.com/superseriousbusiness/gotosocial/internal/gtsmodel" "github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
) )
@ -41,8 +42,8 @@ type GTSCaches interface {
// Block provides access to the gtsmodel Block (account) database cache. // Block provides access to the gtsmodel Block (account) database cache.
Block() *result.Cache[*gtsmodel.Block] Block() *result.Cache[*gtsmodel.Block]
// DomainBlock provides access to the gtsmodel DomainBlock database cache. // DomainBlock provides access to the domain block database cache.
DomainBlock() *result.Cache[*gtsmodel.DomainBlock] DomainBlock() *domain.BlockCache
// Emoji provides access to the gtsmodel Emoji database cache. // Emoji provides access to the gtsmodel Emoji database cache.
Emoji() *result.Cache[*gtsmodel.Emoji] Emoji() *result.Cache[*gtsmodel.Emoji]
@ -74,7 +75,7 @@ func NewGTS() GTSCaches {
type gtsCaches struct { type gtsCaches struct {
account *result.Cache[*gtsmodel.Account] account *result.Cache[*gtsmodel.Account]
block *result.Cache[*gtsmodel.Block] block *result.Cache[*gtsmodel.Block]
domainBlock *result.Cache[*gtsmodel.DomainBlock] domainBlock *domain.BlockCache
emoji *result.Cache[*gtsmodel.Emoji] emoji *result.Cache[*gtsmodel.Emoji]
emojiCategory *result.Cache[*gtsmodel.EmojiCategory] emojiCategory *result.Cache[*gtsmodel.EmojiCategory]
mention *result.Cache[*gtsmodel.Mention] mention *result.Cache[*gtsmodel.Mention]
@ -151,7 +152,7 @@ func (c *gtsCaches) Block() *result.Cache[*gtsmodel.Block] {
return c.block return c.block
} }
func (c *gtsCaches) DomainBlock() *result.Cache[*gtsmodel.DomainBlock] { func (c *gtsCaches) DomainBlock() *domain.BlockCache {
return c.domainBlock return c.domainBlock
} }
@ -212,14 +213,10 @@ func (c *gtsCaches) initBlock() {
} }
func (c *gtsCaches) initDomainBlock() { func (c *gtsCaches) initDomainBlock() {
c.domainBlock = result.NewSized([]result.Lookup{ c.domainBlock = domain.New(
{Name: "Domain"}, config.GetCacheGTSDomainBlockMaxSize(),
}, func(d1 *gtsmodel.DomainBlock) *gtsmodel.DomainBlock { config.GetCacheGTSDomainBlockTTL(),
d2 := new(gtsmodel.DomainBlock) )
*d2 = *d1
return d2
}, config.GetCacheGTSDomainBlockMaxSize())
c.domainBlock.SetTTL(config.GetCacheGTSDomainBlockTTL(), true)
} }
func (c *gtsCaches) initEmoji() { func (c *gtsCaches) initEmoji() {

View file

@ -50,46 +50,52 @@ func normalizeDomain(domain string) (out string, err error) {
func (d *domainDB) CreateDomainBlock(ctx context.Context, block *gtsmodel.DomainBlock) db.Error { func (d *domainDB) CreateDomainBlock(ctx context.Context, block *gtsmodel.DomainBlock) db.Error {
var err error var err error
// Normalize the domain as punycode
block.Domain, err = normalizeDomain(block.Domain) block.Domain, err = normalizeDomain(block.Domain)
if err != nil { if err != nil {
return err return err
} }
return d.state.Caches.GTS.DomainBlock().Store(block, func() error { // Attempt to store domain in DB
_, err := d.conn.NewInsert(). if _, err := d.conn.NewInsert().
Model(block). Model(block).
Exec(ctx) Exec(ctx); err != nil {
return d.conn.ProcessError(err) return d.conn.ProcessError(err)
}) }
// Clear the domain block cache (for later reload)
d.state.Caches.GTS.DomainBlock().Clear()
return nil
} }
func (d *domainDB) GetDomainBlock(ctx context.Context, domain string) (*gtsmodel.DomainBlock, db.Error) { func (d *domainDB) GetDomainBlock(ctx context.Context, domain string) (*gtsmodel.DomainBlock, db.Error) {
var err error var err error
// Normalize the domain as punycode
domain, err = normalizeDomain(domain) domain, err = normalizeDomain(domain)
if err != nil { if err != nil {
return nil, err return nil, err
} }
return d.state.Caches.GTS.DomainBlock().Load("Domain", func() (*gtsmodel.DomainBlock, error) { // Check for easy case, domain referencing *us*
// Check for easy case, domain referencing *us* if domain == "" || domain == config.GetAccountDomain() ||
if domain == "" || domain == config.GetAccountDomain() { domain == config.GetHost() {
return nil, db.ErrNoEntries return nil, db.ErrNoEntries
} }
var block gtsmodel.DomainBlock var block gtsmodel.DomainBlock
q := d.conn. // Look for block matching domain in DB
NewSelect(). q := d.conn.
Model(&block). NewSelect().
Where("? = ?", bun.Ident("domain_block.domain"), domain). Model(&block).
Limit(1) Where("? = ?", bun.Ident("domain_block.domain"), domain)
if err := q.Scan(ctx); err != nil { if err := q.Scan(ctx); err != nil {
return nil, d.conn.ProcessError(err) return nil, d.conn.ProcessError(err)
} }
return &block, nil return &block, nil
}, domain)
} }
func (d *domainDB) DeleteDomainBlock(ctx context.Context, domain string) db.Error { func (d *domainDB) DeleteDomainBlock(ctx context.Context, domain string) db.Error {
@ -108,18 +114,39 @@ func (d *domainDB) DeleteDomainBlock(ctx context.Context, domain string) db.Erro
return d.conn.ProcessError(err) return d.conn.ProcessError(err)
} }
// Clear domain from cache // Clear the domain block cache (for later reload)
d.state.Caches.GTS.DomainBlock().Invalidate(domain) d.state.Caches.GTS.DomainBlock().Clear()
return nil return nil
} }
func (d *domainDB) IsDomainBlocked(ctx context.Context, domain string) (bool, db.Error) { func (d *domainDB) IsDomainBlocked(ctx context.Context, domain string) (bool, db.Error) {
block, err := d.GetDomainBlock(ctx, domain) // Normalize the domain as punycode
if err == nil || err == db.ErrNoEntries { domain, err := normalizeDomain(domain)
return (block != nil), nil if err != nil {
return false, err
} }
return false, err
// Check for easy case, domain referencing *us*
if domain == "" || domain == config.GetAccountDomain() ||
domain == config.GetHost() {
return false, nil
}
// Check the cache for a domain block (hydrating the cache with callback if necessary)
return d.state.Caches.GTS.DomainBlock().IsBlocked(domain, func() ([]string, error) {
var domains []string
// Scan list of all blocked domains from DB
q := d.conn.NewSelect().
Table("domain_blocks").
Column("domain")
if err := q.Scan(ctx, &domains); err != nil {
return nil, d.conn.ProcessError(err)
}
return domains, nil
})
} }
func (d *domainDB) AreDomainsBlocked(ctx context.Context, domains []string) (bool, db.Error) { func (d *domainDB) AreDomainsBlocked(ctx context.Context, domains []string) (bool, db.Error) {

View file

@ -56,6 +56,38 @@ func (suite *DomainTestSuite) TestIsDomainBlocked() {
suite.WithinDuration(time.Now(), domainBlock.CreatedAt, 10*time.Second) suite.WithinDuration(time.Now(), domainBlock.CreatedAt, 10*time.Second)
} }
func (suite *DomainTestSuite) TestIsDomainBlockedWildcard() {
ctx := context.Background()
domainBlock := &gtsmodel.DomainBlock{
ID: "01G204214Y9TNJEBX39C7G88SW",
Domain: "bad.apples",
CreatedByAccountID: suite.testAccounts["admin_account"].ID,
CreatedByAccount: suite.testAccounts["admin_account"],
}
// no domain block exists for the given domain yet
blocked, err := suite.db.IsDomainBlocked(ctx, domainBlock.Domain)
suite.NoError(err)
suite.False(blocked)
err = suite.db.CreateDomainBlock(ctx, domainBlock)
suite.NoError(err)
// Start with the base block domain
domain := domainBlock.Domain
for _, part := range []string{"extra", "domain", "parts"} {
// Prepend the next domain part
domain = part + "." + domain
// Check that domain block is wildcarded for this subdomain
blocked, err = suite.db.IsDomainBlocked(ctx, domainBlock.Domain)
suite.NoError(err)
suite.True(blocked)
}
}
func (suite *DomainTestSuite) TestIsDomainBlockedNonASCII() { func (suite *DomainTestSuite) TestIsDomainBlockedNonASCII() {
ctx := context.Background() ctx := context.Background()