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-rw-r--r--vendor/golang.org/x/crypto/pkcs12/bmp-string.go50
1 files changed, 50 insertions, 0 deletions
diff --git a/vendor/golang.org/x/crypto/pkcs12/bmp-string.go b/vendor/golang.org/x/crypto/pkcs12/bmp-string.go
new file mode 100644
index 000000000..284d2a68f
--- /dev/null
+++ b/vendor/golang.org/x/crypto/pkcs12/bmp-string.go
@@ -0,0 +1,50 @@
+// Copyright 2015 The Go 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 pkcs12
+
+import (
+ "errors"
+ "unicode/utf16"
+)
+
+// bmpString returns s encoded in UCS-2 with a zero terminator.
+func bmpString(s string) ([]byte, error) {
+ // References:
+ // https://tools.ietf.org/html/rfc7292#appendix-B.1
+ // http://en.wikipedia.org/wiki/Plane_(Unicode)#Basic_Multilingual_Plane
+ // - non-BMP characters are encoded in UTF 16 by using a surrogate pair of 16-bit codes
+ // EncodeRune returns 0xfffd if the rune does not need special encoding
+ // - the above RFC provides the info that BMPStrings are NULL terminated.
+
+ ret := make([]byte, 0, 2*len(s)+2)
+
+ for _, r := range s {
+ if t, _ := utf16.EncodeRune(r); t != 0xfffd {
+ return nil, errors.New("pkcs12: string contains characters that cannot be encoded in UCS-2")
+ }
+ ret = append(ret, byte(r/256), byte(r%256))
+ }
+
+ return append(ret, 0, 0), nil
+}
+
+func decodeBMPString(bmpString []byte) (string, error) {
+ if len(bmpString)%2 != 0 {
+ return "", errors.New("pkcs12: odd-length BMP string")
+ }
+
+ // strip terminator if present
+ if l := len(bmpString); l >= 2 && bmpString[l-1] == 0 && bmpString[l-2] == 0 {
+ bmpString = bmpString[:l-2]
+ }
+
+ s := make([]uint16, 0, len(bmpString)/2)
+ for len(bmpString) > 0 {
+ s = append(s, uint16(bmpString[0])<<8+uint16(bmpString[1]))
+ bmpString = bmpString[2:]
+ }
+
+ return string(utf16.Decode(s)), nil
+}