commit badb5f06272b4f2d47b86a7cbe5bdb6dd241d831
Author: Anatoly Prohacky <paa@it-east.ru>
Date:   Sat Jul 30 18:30:44 2022 +1000

    Инициализация библиотеки

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ccfde3b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,28 @@
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+!.vscode/*.code-snippets
+
+# Local History for Visual Studio Code
+.history/
+
+# Built Visual Studio Code Extensions
+*.vsix
+
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..38bb28c
--- /dev/null
+++ b/README.md
@@ -0,0 +1,2 @@
+# Утилиты работы с шифрами
+
diff --git a/base64.go b/base64.go
new file mode 100644
index 0000000..f0b6efe
--- /dev/null
+++ b/base64.go
@@ -0,0 +1,35 @@
+package ciphers
+
+import (
+	"encoding/base64"
+	"strings"
+)
+
+func Base64EncRsa(b1 []byte) string {
+	s1 := base64.StdEncoding.EncodeToString(b1)
+	s2 := ""
+	var LEN int = 76
+	for len(s1) > 76 {
+		s2 = s2 + s1[:LEN] + "\n"
+		s1 = s1[LEN:]
+	}
+	s2 = s2 + s1
+	return s2
+}
+
+func Base64DecRsa(s1 string) ([]byte, error) {
+	s1 = strings.Replace(s1, "\n", "", -1)
+	s1 = strings.Replace(s1, "\r", "", -1)
+	s1 = strings.Replace(s1, " ", "", -1)
+	return base64.StdEncoding.DecodeString(s1)
+}
+
+func Base64Enc(b1 []byte) string {
+
+	return base64.StdEncoding.EncodeToString(b1)
+}
+
+func Base64Dec(s1 string) ([]byte, error) {
+
+	return base64.StdEncoding.DecodeString(s1)
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..7c84267
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module gitstore.ru/tolikproh/chiphers
+
+go 1.18
diff --git a/rsa.go b/rsa.go
new file mode 100644
index 0000000..4326fbb
--- /dev/null
+++ b/rsa.go
@@ -0,0 +1,150 @@
+package ciphers
+
+import (
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"hash"
+)
+
+var (
+	ErrPubKeyNotCorrect = errors.New("rsa public key is not correct")
+)
+
+// GenerateKeyPair generates a new key pair
+func GenerateKeyPair(bits int) (*rsa.PrivateKey, error) {
+	privkey, err := rsa.GenerateKey(rand.Reader, bits)
+	if err != nil {
+		return nil, err
+	}
+	return privkey, nil
+}
+
+// PrivateKeyToBytes private key to bytes
+func PrivateKeyToBytes(priv *rsa.PrivateKey) []byte {
+	privBytes := pem.EncodeToMemory(
+		&pem.Block{
+			Type:  "RSA PRIVATE KEY",
+			Bytes: x509.MarshalPKCS1PrivateKey(priv),
+		},
+	)
+
+	return privBytes
+}
+
+// PublicKeyToBytes public key to bytes
+func PublicKeyToBytes(pub *rsa.PrivateKey) ([]byte, error) {
+	pubASN1, err := x509.MarshalPKIXPublicKey(&pub.PublicKey)
+	if err != nil {
+		return nil, err
+	}
+
+	pubBytes := pem.EncodeToMemory(&pem.Block{
+		Type:  "PUBLIC KEY",
+		Bytes: pubASN1,
+	})
+
+	return pubBytes, nil
+}
+
+func BytesRsaKeyToGo(priv, pub []byte) (*rsa.PrivateKey, error) {
+
+	key, err := BytesToPrivateKey(priv)
+	if err != nil {
+		return nil, err
+	}
+
+	pubKey, err := BytesToPublicKey(pub)
+	if err != nil {
+		return nil, err
+	}
+
+	key.PublicKey = rsa.PublicKey{
+		N: pubKey.N,
+		E: pubKey.E,
+	}
+
+	return key, nil
+}
+
+//
+func BytesPublicKeyToGo(pub []byte) (*rsa.PublicKey, error) {
+
+	pubKey, err := BytesToPublicKey(pub)
+	if err != nil {
+		return nil, err
+	}
+
+	return &rsa.PublicKey{
+		N: pubKey.N,
+		E: pubKey.E,
+	}, nil
+}
+
+// BytesToPrivateKey bytes to private key
+func BytesToPrivateKey(priv []byte) (*rsa.PrivateKey, error) {
+	block, _ := pem.Decode(priv)
+	enc := x509.IsEncryptedPEMBlock(block)
+	b := block.Bytes
+	var err error
+	if enc {
+		//log.Println("is encrypted pem block")
+		b, err = x509.DecryptPEMBlock(block, nil)
+		if err != nil {
+			return nil, err
+		}
+	}
+	key, err := x509.ParsePKCS1PrivateKey(b)
+	if err != nil {
+		return nil, err
+	}
+	return key, nil
+}
+
+// BytesToPublicKey bytes to public key
+func BytesToPublicKey(pub []byte) (*rsa.PublicKey, error) {
+	block, _ := pem.Decode(pub)
+	enc := x509.IsEncryptedPEMBlock(block)
+	b := block.Bytes
+	var err error
+	if enc {
+		//log.Println("is encrypted pem block")
+		b, err = x509.DecryptPEMBlock(block, nil)
+		if err != nil {
+			return nil, err
+		}
+	}
+	ifc, err := x509.ParsePKIXPublicKey(b)
+	if err != nil {
+		return nil, err
+	}
+	key, ok := ifc.(*rsa.PublicKey)
+	if !ok {
+		return nil, ErrPubKeyNotCorrect
+	}
+	return key, nil
+}
+
+// EncryptWithPublicKey OAEP encrypts data with public key
+func EncryptWithPublicKeyOAEP(hash hash.Hash, msg []byte, pub *rsa.PublicKey) ([]byte, error) {
+	//hash := sha512.New()
+	//hash := sha1.New()
+	ciphertext, err := rsa.EncryptOAEP(hash, rand.Reader, pub, msg, nil)
+	if err != nil {
+		return nil, err
+	}
+	return ciphertext, nil
+}
+
+// DecryptWithPrivateKey OAEP decrypts data with private key
+func DecryptWithPrivateKeyOAEP(hash hash.Hash, ciphertext []byte, priv *rsa.PrivateKey) ([]byte, error) {
+	//hash := sha512.New()
+	//hash := sha1.New()
+	plaintext, err := rsa.DecryptOAEP(hash, rand.Reader, priv, ciphertext, nil)
+	if err != nil {
+		return nil, err
+	}
+	return plaintext, nil
+}