diff options
Diffstat (limited to 'libgo/go/crypto/rsa/pss.go')
| -rw-r--r-- | libgo/go/crypto/rsa/pss.go | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/libgo/go/crypto/rsa/pss.go b/libgo/go/crypto/rsa/pss.go index f9abec3949..e9f2908250 100644 --- a/libgo/go/crypto/rsa/pss.go +++ b/libgo/go/crypto/rsa/pss.go @@ -4,7 +4,7 @@ package rsa -// This file implementes the PSS signature scheme [1]. +// This file implements the PSS signature scheme [1]. // // [1] http://www.rsa.com/rsalabs/pkcs/files/h11300-wp-pkcs-1v2-2-rsa-cryptography-standard.pdf @@ -189,7 +189,7 @@ func emsaPSSVerify(mHash, em []byte, emBits, sLen int, hash hash.Hash) error { // signPSSWithSalt calculates the signature of hashed using PSS [1] with specified salt. // Note that hashed must be the result of hashing the input message using the -// given hash funcion. salt is a random sequence of bytes whose length will be +// given hash function. salt is a random sequence of bytes whose length will be // later used to verify the signature. func signPSSWithSalt(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed, salt []byte) (s []byte, err error) { nBits := priv.N.BitLen() @@ -222,6 +222,17 @@ type PSSOptions struct { // signature. It can either be a number of bytes, or one of the special // PSSSaltLength constants. SaltLength int + + // Hash, if not zero, overrides the hash function passed to SignPSS. + // This is the only way to specify the hash function when using the + // crypto.Signer interface. + Hash crypto.Hash +} + +// HashFunc returns pssOpts.Hash so that PSSOptions implements +// crypto.SignerOpts. +func (pssOpts *PSSOptions) HashFunc() crypto.Hash { + return pssOpts.Hash } func (opts *PSSOptions) saltLength() int { @@ -233,7 +244,7 @@ func (opts *PSSOptions) saltLength() int { // SignPSS calculates the signature of hashed using RSASSA-PSS [1]. // Note that hashed must be the result of hashing the input message using the -// given hash funcion. The opts argument may be nil, in which case sensible +// given hash function. The opts argument may be nil, in which case sensible // defaults are used. func SignPSS(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed []byte, opts *PSSOptions) (s []byte, err error) { saltLength := opts.saltLength() @@ -244,6 +255,10 @@ func SignPSS(rand io.Reader, priv *PrivateKey, hash crypto.Hash, hashed []byte, saltLength = hash.Size() } + if opts.Hash != 0 { + hash = opts.Hash + } + salt := make([]byte, saltLength) if _, err = io.ReadFull(rand, salt); err != nil { return |