Files
filou/contract/contract_generators.go
2014-11-15 12:07:11 -08:00

100 lines
3.1 KiB
Go

package contract
import (
"crypto/rand"
"crypto/rsa"
"encoding/json"
"errors"
"os"
"path"
"github.com/didiercrunch/filou/keys"
"github.com/didiercrunch/filou/shared"
)
type ContractsGenerator struct {
publicKey *keys.RSAPublicKey
privateKey *keys.RSAPrivateKey
privateContract *PrivateContract
publicContract *PublicContract
}
func (this *ContractsGenerator) ensureDirectoryExists(dir string) error {
stat, err := os.Stat(dir)
if os.IsNotExist(err) {
return os.Mkdir(dir, 0700)
} else if err != nil {
return err
} else if !stat.IsDir() {
return errors.New(dir + " is not a directory")
}
return nil
}
func (this *ContractsGenerator) saveContractAsJSON(contract interface{}, filepath string) error {
w, err := os.Create(filepath)
if err != nil {
return err
}
enc := json.NewEncoder(w)
return enc.Encode(contract)
}
func (this *ContractsGenerator) saveContracts(dirPath string) error {
if err := this.ensureDirectoryExists(dirPath); err != nil {
return err
}
if err := this.saveContractAsJSON(this.publicContract, path.Join(dirPath, "public_contract.json")); err != nil {
return err
}
return this.saveContractAsJSON(this.privateContract, path.Join(dirPath, "private_contract.json"))
}
func (this *ContractsGenerator) createRSAKeys(size int) error {
rsaPrivateKey, err := rsa.GenerateKey(rand.Reader, size)
if err != nil {
return errors.New("cannot generate the rsa public/private key pair\n" + err.Error())
}
this.privateKey = keys.NewRSAPrivateKey(rsaPrivateKey)
this.publicKey = keys.NewRSAPublicKey(&rsaPrivateKey.PublicKey)
return nil
}
func (this *ContractsGenerator) createPrivateContractWithGoodDefaultValues(key *keys.RSAPrivateKey) {
this.privateContract = new(PrivateContract)
this.privateContract.AcceptedAsynchronousEncryptionScheme = []string{"rsa_oaep"}
this.privateContract.AcceptedSignatureScheme = []string{"rsa_pss"}
this.privateContract.AcceptedBlockCypherModes = []string{"ofb"}
this.privateContract.AcceptedBlockCyphers = []string{"aes"}
this.privateContract.RSAPrivateKey = []*keys.RSAPrivateKey{key}
this.privateContract.RSAPublicKey = []*keys.RSAPublicKey{}
}
func (this *ContractsGenerator) createPublicContractWithGoodDefaultValues(key *keys.RSAPublicKey) {
this.publicContract = new(PublicContract)
this.privateContract.AcceptedAsynchronousEncryptionScheme = []string{"rsa_oaep"}
this.privateContract.AcceptedSignatureScheme = []string{"rsa_pss"}
this.privateContract.AcceptedBlockCypherModes = []string{"ofb"}
this.privateContract.AcceptedBlockCyphers = []string{"aes"}
this.privateContract.AcceptedHashes = []string{"sha384", "sha512", "sha256"}
this.privateContract.RSAPublicKey = []*keys.RSAPublicKey{key}
}
func (this *ContractsGenerator) createContracts(keySize int) error {
if err := this.createRSAKeys(keySize); err != nil {
return err
}
this.createPrivateContractWithGoodDefaultValues(this.privateKey)
this.createPublicContractWithGoodDefaultValues(this.publicKey)
return nil
}
func (this *ContractsGenerator) CreateContracts(size int) error {
if err := this.createContracts(size); err != nil {
return err
}
return this.saveContracts(shared.GetEcryptoDir())
}