mirror of
https://github.com/TwiN/gatus.git
synced 2024-11-22 16:03:44 +01:00
76 lines
1.8 KiB
Go
76 lines
1.8 KiB
Go
/*-
|
|
* Copyright 2014 Square Inc.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
package josecipher
|
|
|
|
import (
|
|
"crypto"
|
|
"encoding/binary"
|
|
"hash"
|
|
"io"
|
|
)
|
|
|
|
type concatKDF struct {
|
|
z, info []byte
|
|
i uint32
|
|
cache []byte
|
|
hasher hash.Hash
|
|
}
|
|
|
|
// NewConcatKDF builds a KDF reader based on the given inputs.
|
|
func NewConcatKDF(hash crypto.Hash, z, algID, ptyUInfo, ptyVInfo, supPubInfo, supPrivInfo []byte) io.Reader {
|
|
buffer := make([]byte, uint64(len(algID))+uint64(len(ptyUInfo))+uint64(len(ptyVInfo))+uint64(len(supPubInfo))+uint64(len(supPrivInfo)))
|
|
n := 0
|
|
n += copy(buffer, algID)
|
|
n += copy(buffer[n:], ptyUInfo)
|
|
n += copy(buffer[n:], ptyVInfo)
|
|
n += copy(buffer[n:], supPubInfo)
|
|
copy(buffer[n:], supPrivInfo)
|
|
|
|
hasher := hash.New()
|
|
|
|
return &concatKDF{
|
|
z: z,
|
|
info: buffer,
|
|
hasher: hasher,
|
|
cache: []byte{},
|
|
i: 1,
|
|
}
|
|
}
|
|
|
|
func (ctx *concatKDF) Read(out []byte) (int, error) {
|
|
copied := copy(out, ctx.cache)
|
|
ctx.cache = ctx.cache[copied:]
|
|
|
|
for copied < len(out) {
|
|
ctx.hasher.Reset()
|
|
|
|
// Write on a hash.Hash never fails
|
|
_ = binary.Write(ctx.hasher, binary.BigEndian, ctx.i)
|
|
_, _ = ctx.hasher.Write(ctx.z)
|
|
_, _ = ctx.hasher.Write(ctx.info)
|
|
|
|
hash := ctx.hasher.Sum(nil)
|
|
chunkCopied := copy(out[copied:], hash)
|
|
copied += chunkCopied
|
|
ctx.cache = hash[chunkCopied:]
|
|
|
|
ctx.i++
|
|
}
|
|
|
|
return copied, nil
|
|
}
|