1 files changed, 29 insertions, 15 deletions

diff --git a/vendor/golang.org/x/crypto/openpgp/packet/packet.go b/vendor/golang.org/x/crypto/openpgp/packet/packet.go
index 3eded93..5af64c5 100644
--- a/vendor/golang.org/x/crypto/openpgp/packet/packet.go
+++ b/vendor/golang.org/x/crypto/openpgp/packet/packet.go
@@ -11,10 +11,12 @@ import (
         "crypto/aes"
         "crypto/cipher"
         "crypto/des"
-        "golang.org/x/crypto/cast5"
-        "golang.org/x/crypto/openpgp/errors"
+        "crypto/rsa"
         "io"
         "math/big"
+
+        "golang.org/x/crypto/cast5"
+        "golang.org/x/crypto/openpgp/errors"
 )
 
 // readFull is the same as io.ReadFull except that reading zero bytes returns
@@ -402,14 +404,16 @@ const (
 type PublicKeyAlgorithm uint8
 
 const (
-        PubKeyAlgoRSA            PublicKeyAlgorithm = 1
-        PubKeyAlgoRSAEncryptOnly PublicKeyAlgorithm = 2
-        PubKeyAlgoRSASignOnly    PublicKeyAlgorithm = 3
-        PubKeyAlgoElGamal        PublicKeyAlgorithm = 16
-        PubKeyAlgoDSA            PublicKeyAlgorithm = 17
+        PubKeyAlgoRSA     PublicKeyAlgorithm = 1
+        PubKeyAlgoElGamal PublicKeyAlgorithm = 16
+        PubKeyAlgoDSA     PublicKeyAlgorithm = 17
         // RFC 6637, Section 5.
         PubKeyAlgoECDH  PublicKeyAlgorithm = 18
         PubKeyAlgoECDSA PublicKeyAlgorithm = 19
+
+        // Deprecated in RFC 4880, Section 13.5. Use key flags instead.
+        PubKeyAlgoRSAEncryptOnly PublicKeyAlgorithm = 2
+        PubKeyAlgoRSASignOnly    PublicKeyAlgorithm = 3
 )
 
 // CanEncrypt returns true if it's possible to encrypt a message to a public
@@ -500,19 +504,17 @@ func readMPI(r io.Reader) (mpi []byte, bitLength uint16, err error) {
         numBytes := (int(bitLength) + 7) / 8
         mpi = make([]byte, numBytes)
         _, err = readFull(r, mpi)
-        return
-}
-
-// mpiLength returns the length of the given *big.Int when serialized as an
-// MPI.
-func mpiLength(n *big.Int) (mpiLengthInBytes int) {
-        mpiLengthInBytes = 2 /* MPI length */
-        mpiLengthInBytes += (n.BitLen() + 7) / 8
+        // According to RFC 4880 3.2. we should check that the MPI has no leading
+        // zeroes (at least when not an encrypted MPI?), but this implementation
+        // does generate leading zeroes, so we keep accepting them.
         return
 }
 
 // writeMPI serializes a big integer to w.
 func writeMPI(w io.Writer, bitLength uint16, mpiBytes []byte) (err error) {
+        // Note that we can produce leading zeroes, in violation of RFC 4880 3.2.
+        // Implementations seem to be tolerant of them, and stripping them would
+        // make it complex to guarantee matching re-serialization.
         _, err = w.Write([]byte{byte(bitLength >> 8), byte(bitLength)})
         if err == nil {
                 _, err = w.Write(mpiBytes)
@@ -525,6 +527,18 @@ func writeBig(w io.Writer, i *big.Int) error {
         return writeMPI(w, uint16(i.BitLen()), i.Bytes())
 }
 
+// padToKeySize left-pads a MPI with zeroes to match the length of the
+// specified RSA public.
+func padToKeySize(pub *rsa.PublicKey, b []byte) []byte {
+        k := (pub.N.BitLen() + 7) / 8
+        if len(b) >= k {
+                return b
+        }
+        bb := make([]byte, k)
+        copy(bb[len(bb)-len(b):], b)
+        return bb
+}
+
 // CompressionAlgo Represents the different compression algorithms
 // supported by OpenPGP (except for BZIP2, which is not currently
 // supported). See Section 9.3 of RFC 4880.