forked from jchavannes/go-pgp
/
decrypt.go
51 lines (45 loc) · 1.26 KB
/
decrypt.go
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package go_pgp
import (
"bytes"
"compress/gzip"
_ "crypto/sha256"
"errors"
"fmt"
"golang.org/x/crypto/openpgp"
"golang.org/x/crypto/openpgp/armor"
_ "golang.org/x/crypto/ripemd160"
"io/ioutil"
)
func Decrypt(entity *openpgp.Entity, encrypted []byte) ([]byte, error) {
// Decode message
block, err := armor.Decode(bytes.NewReader(encrypted))
if err != nil {
return []byte{}, fmt.Errorf("Error decoding: %v", err)
}
if block.Type != "Message" {
return []byte{}, errors.New("Invalid message type")
}
// Decrypt message
entityList := openpgp.EntityList{entity}
messageReader, err := openpgp.ReadMessage(block.Body, entityList, nil, nil)
if err != nil {
return []byte{}, fmt.Errorf("Error reading message: %v", err)
}
read, err := ioutil.ReadAll(messageReader.UnverifiedBody)
if err != nil {
return []byte{}, fmt.Errorf("Error reading unverified body: %v", err)
}
// Uncompress message
reader := bytes.NewReader(read)
uncompressed, err := gzip.NewReader(reader)
if err != nil {
return []byte{}, fmt.Errorf("Error initializing gzip reader: %v", err)
}
defer uncompressed.Close()
out, err := ioutil.ReadAll(uncompressed)
if err != nil {
return []byte{}, err
}
// Return output - an unencoded, unencrypted, and uncompressed message
return out, nil
}