crypto/

README

mtls/crypto/tls

1. mtls/crypto/tls is based on Golang1.12.7's standard library crypto/tls
2. Add tls_custom.go that support smooth upgrade on TLS
3. Modify import paths
4. Call TransferSetTLSInfo() to set transfer info when TLS handshake is successful
5. Reuse tls Conn's outBuf to reduce memory in large number of idle connection
6. add HasMoreData to let user know whether the tls buffer has unread data
7. tls_custom.go: add a certificates cache to reduce memory usage.
8. use certificates cache to optimize handshake:
   handshake_client.go: verifyServerCertificate use LoadOrStoreCertificate instead of x509.ParseCertificate
   handshake_server.go: processCertsFromClient use LoadOrStoreCertificate instead of x509.ParseCertificate 
Maybe we can optimize it in x509.ParseCertificate / add cache expire later.
9. tls_custom.go: add mtls/crypto/tls.Conn.SetConnectionState() to manually set the tls connection state.
10. tls_custom.go: add mtls/crypto/tls.Conn.SetConfig() to manually set tls config

add supports for tls1.3-gm
see draft:https://datatracker.ietf.org/doc/draft-yang-tls-tls13-sm-suites/

run tls test
    a. go to pkg/mtls
    b. go test -v ./...