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Diffstat (limited to 'vendor/github.com/gorilla/websocket/util.go')
-rw-r--r--vendor/github.com/gorilla/websocket/util.go283
1 files changed, 283 insertions, 0 deletions
diff --git a/vendor/github.com/gorilla/websocket/util.go b/vendor/github.com/gorilla/websocket/util.go
new file mode 100644
index 000000000..7bf2f66c6
--- /dev/null
+++ b/vendor/github.com/gorilla/websocket/util.go
@@ -0,0 +1,283 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+ "crypto/rand"
+ "crypto/sha1"
+ "encoding/base64"
+ "io"
+ "net/http"
+ "strings"
+ "unicode/utf8"
+)
+
+var keyGUID = []byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
+
+func computeAcceptKey(challengeKey string) string {
+ h := sha1.New()
+ h.Write([]byte(challengeKey))
+ h.Write(keyGUID)
+ return base64.StdEncoding.EncodeToString(h.Sum(nil))
+}
+
+func generateChallengeKey() (string, error) {
+ p := make([]byte, 16)
+ if _, err := io.ReadFull(rand.Reader, p); err != nil {
+ return "", err
+ }
+ return base64.StdEncoding.EncodeToString(p), nil
+}
+
+// Token octets per RFC 2616.
+var isTokenOctet = [256]bool{
+ '!': true,
+ '#': true,
+ '$': true,
+ '%': true,
+ '&': true,
+ '\'': true,
+ '*': true,
+ '+': true,
+ '-': true,
+ '.': true,
+ '0': true,
+ '1': true,
+ '2': true,
+ '3': true,
+ '4': true,
+ '5': true,
+ '6': true,
+ '7': true,
+ '8': true,
+ '9': true,
+ 'A': true,
+ 'B': true,
+ 'C': true,
+ 'D': true,
+ 'E': true,
+ 'F': true,
+ 'G': true,
+ 'H': true,
+ 'I': true,
+ 'J': true,
+ 'K': true,
+ 'L': true,
+ 'M': true,
+ 'N': true,
+ 'O': true,
+ 'P': true,
+ 'Q': true,
+ 'R': true,
+ 'S': true,
+ 'T': true,
+ 'U': true,
+ 'W': true,
+ 'V': true,
+ 'X': true,
+ 'Y': true,
+ 'Z': true,
+ '^': true,
+ '_': true,
+ '`': true,
+ 'a': true,
+ 'b': true,
+ 'c': true,
+ 'd': true,
+ 'e': true,
+ 'f': true,
+ 'g': true,
+ 'h': true,
+ 'i': true,
+ 'j': true,
+ 'k': true,
+ 'l': true,
+ 'm': true,
+ 'n': true,
+ 'o': true,
+ 'p': true,
+ 'q': true,
+ 'r': true,
+ 's': true,
+ 't': true,
+ 'u': true,
+ 'v': true,
+ 'w': true,
+ 'x': true,
+ 'y': true,
+ 'z': true,
+ '|': true,
+ '~': true,
+}
+
+// skipSpace returns a slice of the string s with all leading RFC 2616 linear
+// whitespace removed.
+func skipSpace(s string) (rest string) {
+ i := 0
+ for ; i < len(s); i++ {
+ if b := s[i]; b != ' ' && b != '\t' {
+ break
+ }
+ }
+ return s[i:]
+}
+
+// nextToken returns the leading RFC 2616 token of s and the string following
+// the token.
+func nextToken(s string) (token, rest string) {
+ i := 0
+ for ; i < len(s); i++ {
+ if !isTokenOctet[s[i]] {
+ break
+ }
+ }
+ return s[:i], s[i:]
+}
+
+// nextTokenOrQuoted returns the leading token or quoted string per RFC 2616
+// and the string following the token or quoted string.
+func nextTokenOrQuoted(s string) (value string, rest string) {
+ if !strings.HasPrefix(s, "\"") {
+ return nextToken(s)
+ }
+ s = s[1:]
+ for i := 0; i < len(s); i++ {
+ switch s[i] {
+ case '"':
+ return s[:i], s[i+1:]
+ case '\\':
+ p := make([]byte, len(s)-1)
+ j := copy(p, s[:i])
+ escape := true
+ for i = i + 1; i < len(s); i++ {
+ b := s[i]
+ switch {
+ case escape:
+ escape = false
+ p[j] = b
+ j++
+ case b == '\\':
+ escape = true
+ case b == '"':
+ return string(p[:j]), s[i+1:]
+ default:
+ p[j] = b
+ j++
+ }
+ }
+ return "", ""
+ }
+ }
+ return "", ""
+}
+
+// equalASCIIFold returns true if s is equal to t with ASCII case folding as
+// defined in RFC 4790.
+func equalASCIIFold(s, t string) bool {
+ for s != "" && t != "" {
+ sr, size := utf8.DecodeRuneInString(s)
+ s = s[size:]
+ tr, size := utf8.DecodeRuneInString(t)
+ t = t[size:]
+ if sr == tr {
+ continue
+ }
+ if 'A' <= sr && sr <= 'Z' {
+ sr = sr + 'a' - 'A'
+ }
+ if 'A' <= tr && tr <= 'Z' {
+ tr = tr + 'a' - 'A'
+ }
+ if sr != tr {
+ return false
+ }
+ }
+ return s == t
+}
+
+// tokenListContainsValue returns true if the 1#token header with the given
+// name contains a token equal to value with ASCII case folding.
+func tokenListContainsValue(header http.Header, name string, value string) bool {
+headers:
+ for _, s := range header[name] {
+ for {
+ var t string
+ t, s = nextToken(skipSpace(s))
+ if t == "" {
+ continue headers
+ }
+ s = skipSpace(s)
+ if s != "" && s[0] != ',' {
+ continue headers
+ }
+ if equalASCIIFold(t, value) {
+ return true
+ }
+ if s == "" {
+ continue headers
+ }
+ s = s[1:]
+ }
+ }
+ return false
+}
+
+// parseExtensions parses WebSocket extensions from a header.
+func parseExtensions(header http.Header) []map[string]string {
+ // From RFC 6455:
+ //
+ // Sec-WebSocket-Extensions = extension-list
+ // extension-list = 1#extension
+ // extension = extension-token *( ";" extension-param )
+ // extension-token = registered-token
+ // registered-token = token
+ // extension-param = token [ "=" (token | quoted-string) ]
+ // ;When using the quoted-string syntax variant, the value
+ // ;after quoted-string unescaping MUST conform to the
+ // ;'token' ABNF.
+
+ var result []map[string]string
+headers:
+ for _, s := range header["Sec-Websocket-Extensions"] {
+ for {
+ var t string
+ t, s = nextToken(skipSpace(s))
+ if t == "" {
+ continue headers
+ }
+ ext := map[string]string{"": t}
+ for {
+ s = skipSpace(s)
+ if !strings.HasPrefix(s, ";") {
+ break
+ }
+ var k string
+ k, s = nextToken(skipSpace(s[1:]))
+ if k == "" {
+ continue headers
+ }
+ s = skipSpace(s)
+ var v string
+ if strings.HasPrefix(s, "=") {
+ v, s = nextTokenOrQuoted(skipSpace(s[1:]))
+ s = skipSpace(s)
+ }
+ if s != "" && s[0] != ',' && s[0] != ';' {
+ continue headers
+ }
+ ext[k] = v
+ }
+ if s != "" && s[0] != ',' {
+ continue headers
+ }
+ result = append(result, ext)
+ if s == "" {
+ continue headers
+ }
+ s = s[1:]
+ }
+ }
+ return result
+}