Fix the build (move out of internal)

socketserver/server/utils.go

@@ -0,0 +1,175 @@
+package server
+
+import (
+	"bytes"
+	"crypto/rand"
+	"encoding/base64"
+	"errors"
+	"golang.org/x/crypto/nacl/box"
+	"log"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+func FillCryptoRandom(buf []byte) error {
+	remaining := len(buf)
+	for remaining > 0 {
+		count, err := rand.Read(buf)
+		if err != nil {
+			return err
+		}
+		remaining -= count
+	}
+	return nil
+}
+
+func New4KByteBuffer() interface{} {
+	return make([]byte, 0, 4096)
+}
+
+func SealRequest(form url.Values) (url.Values, error) {
+	var nonce [24]byte
+	var err error
+
+	err = FillCryptoRandom(nonce[:])
+	if err != nil {
+		return nil, err
+	}
+
+	cipherMsg := box.SealAfterPrecomputation(nil, []byte(form.Encode()), &nonce, &backendSharedKey)
+
+	bufMessage := new(bytes.Buffer)
+	enc := base64.NewEncoder(base64.URLEncoding, bufMessage)
+	enc.Write(cipherMsg)
+	enc.Close()
+	cipherString := bufMessage.String()
+
+	bufNonce := new(bytes.Buffer)
+	enc = base64.NewEncoder(base64.URLEncoding, bufNonce)
+	enc.Write(nonce[:])
+	enc.Close()
+	nonceString := bufNonce.String()
+
+	retval := url.Values{
+		"nonce": []string{nonceString},
+		"msg":   []string{cipherString},
+		"id":    []string{strconv.Itoa(serverID)},
+	}
+
+	return retval, nil
+}
+
+var ErrorShortNonce = errors.New("Nonce too short.")
+var ErrorInvalidSignature = errors.New("Invalid signature or contents")
+
+func UnsealRequest(form url.Values) (url.Values, error) {
+	var nonce [24]byte
+
+	nonceString := form.Get("nonce")
+	dec := base64.NewDecoder(base64.URLEncoding, strings.NewReader(nonceString))
+	count, err := dec.Read(nonce[:])
+	if err != nil {
+		return nil, err
+	}
+	if count != 24 {
+		return nil, ErrorShortNonce
+	}
+
+	cipherString := form.Get("msg")
+	dec = base64.NewDecoder(base64.URLEncoding, strings.NewReader(cipherString))
+	cipherBuffer := new(bytes.Buffer)
+	cipherBuffer.ReadFrom(dec)
+
+	message, ok := box.OpenAfterPrecomputation(nil, cipherBuffer.Bytes(), &nonce, &backendSharedKey)
+	if !ok {
+		return nil, ErrorInvalidSignature
+	}
+
+	retValues, err := url.ParseQuery(string(message))
+	if err != nil {
+		// Assume that the signature was accidentally correct but the contents were garbage
+		log.Println("Error unsealing request:", err)
+		return nil, ErrorInvalidSignature
+	}
+
+	return retValues, nil
+}
+
+func AddToSliceS(ary *[]string, val string) bool {
+	slice := *ary
+	for _, v := range slice {
+		if v == val {
+			return false
+		}
+	}
+
+	slice = append(slice, val)
+	*ary = slice
+	return true
+}
+
+func RemoveFromSliceS(ary *[]string, val string) bool {
+	slice := *ary
+	var idx int = -1
+	for i, v := range slice {
+		if v == val {
+			idx = i
+			break
+		}
+	}
+	if idx == -1 {
+		return false
+	}
+
+	slice[idx] = slice[len(slice)-1]
+	slice = slice[:len(slice)-1]
+	*ary = slice
+	return true
+}
+
+func AddToSliceC(ary *[]chan<- ClientMessage, val chan<- ClientMessage) bool {
+	slice := *ary
+	for _, v := range slice {
+		if v == val {
+			return false
+		}
+	}
+
+	slice = append(slice, val)
+	*ary = slice
+	return true
+}
+
+func RemoveFromSliceC(ary *[]chan<- ClientMessage, val chan<- ClientMessage) bool {
+	slice := *ary
+	var idx int = -1
+	for i, v := range slice {
+		if v == val {
+			idx = i
+			break
+		}
+	}
+	if idx == -1 {
+		return false
+	}
+
+	slice[idx] = slice[len(slice)-1]
+	slice = slice[:len(slice)-1]
+	*ary = slice
+	return true
+}
+
+func AddToSliceB(ary *[]bunchSubscriber, client *ClientInfo, mid int) bool {
+	newSub := bunchSubscriber{Client: client, MessageID: mid}
+	slice := *ary
+	for _, v := range slice {
+		if v == newSub {
+			return false
+		}
+	}
+
+	slice = append(slice, newSub)
+	*ary = slice
+	return true
+}