cloudflared-mirror/vendor/github.com/quic-go/quic-go/token_store.go

117 lines
2.5 KiB
Go

package quic
import (
"sync"
list "github.com/quic-go/quic-go/internal/utils/linkedlist"
)
type singleOriginTokenStore struct {
tokens []*ClientToken
len int
p int
}
func newSingleOriginTokenStore(size int) *singleOriginTokenStore {
return &singleOriginTokenStore{tokens: make([]*ClientToken, size)}
}
func (s *singleOriginTokenStore) Add(token *ClientToken) {
s.tokens[s.p] = token
s.p = s.index(s.p + 1)
s.len = min(s.len+1, len(s.tokens))
}
func (s *singleOriginTokenStore) Pop() *ClientToken {
s.p = s.index(s.p - 1)
token := s.tokens[s.p]
s.tokens[s.p] = nil
s.len = max(s.len-1, 0)
return token
}
func (s *singleOriginTokenStore) Len() int {
return s.len
}
func (s *singleOriginTokenStore) index(i int) int {
mod := len(s.tokens)
return (i + mod) % mod
}
type lruTokenStoreEntry struct {
key string
cache *singleOriginTokenStore
}
type lruTokenStore struct {
mutex sync.Mutex
m map[string]*list.Element[*lruTokenStoreEntry]
q *list.List[*lruTokenStoreEntry]
capacity int
singleOriginSize int
}
var _ TokenStore = &lruTokenStore{}
// NewLRUTokenStore creates a new LRU cache for tokens received by the client.
// maxOrigins specifies how many origins this cache is saving tokens for.
// tokensPerOrigin specifies the maximum number of tokens per origin.
func NewLRUTokenStore(maxOrigins, tokensPerOrigin int) TokenStore {
return &lruTokenStore{
m: make(map[string]*list.Element[*lruTokenStoreEntry]),
q: list.New[*lruTokenStoreEntry](),
capacity: maxOrigins,
singleOriginSize: tokensPerOrigin,
}
}
func (s *lruTokenStore) Put(key string, token *ClientToken) {
s.mutex.Lock()
defer s.mutex.Unlock()
if el, ok := s.m[key]; ok {
entry := el.Value
entry.cache.Add(token)
s.q.MoveToFront(el)
return
}
if s.q.Len() < s.capacity {
entry := &lruTokenStoreEntry{
key: key,
cache: newSingleOriginTokenStore(s.singleOriginSize),
}
entry.cache.Add(token)
s.m[key] = s.q.PushFront(entry)
return
}
elem := s.q.Back()
entry := elem.Value
delete(s.m, entry.key)
entry.key = key
entry.cache = newSingleOriginTokenStore(s.singleOriginSize)
entry.cache.Add(token)
s.q.MoveToFront(elem)
s.m[key] = elem
}
func (s *lruTokenStore) Pop(key string) *ClientToken {
s.mutex.Lock()
defer s.mutex.Unlock()
var token *ClientToken
if el, ok := s.m[key]; ok {
s.q.MoveToFront(el)
cache := el.Value.cache
token = cache.Pop()
if cache.Len() == 0 {
s.q.Remove(el)
delete(s.m, key)
}
}
return token
}