added base mechanism to add public keys from the propogated from the IPTable

p2p/ssh_autorisation.go

@@ -0,0 +1,123 @@
+// NOTE: Most of the code snippet was generated using ChatGPT
+// Prompt used: "generate go program to read and populate ssh authorization file"
+
+package p2p
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// GetAuthorizedKeysPath returns the path to the authorized_keys file
+func GetAuthorizedKeysPath() (string, error) {
+	homeDir, err := os.UserHomeDir()
+	if err != nil {
+		return "", fmt.Errorf("could not find home directory: %v", err)
+	}
+	return filepath.Join(homeDir, ".ssh", "authorized_keys"), nil
+}
+
+// ReadAuthorizedKeys reads and returns the current contents of the authorized_keys file as a map
+func ReadAuthorizedKeys(path string) (map[string]bool, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return nil, fmt.Errorf("could not open authorized_keys file: %v", err)
+	}
+	defer file.Close()
+
+	keys := make(map[string]bool)
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		// Skip empty lines and comments
+		if line != "" && !strings.HasPrefix(line, "#") {
+			keys[line] = true
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error reading authorized_keys file: %v", err)
+	}
+	return keys, nil
+}
+
+// AddKeyToAuthorizedKeys adds a new key to the authorized_keys file if it doesn’t already exist
+func AddKeyToAuthorizedKeys(path, newKey string) error {
+	keys, err := ReadAuthorizedKeys(path)
+	if err != nil {
+		return err
+	}
+
+	// Check if the key already exists in the map
+	if keys[newKey] {
+		return errors.New("key already exists in authorized_keys")
+	}
+
+	// Append the new key
+	file, err := os.OpenFile(path, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
+	if err != nil {
+		return fmt.Errorf("could not open authorized_keys file for writing: %v", err)
+	}
+	defer file.Close()
+
+	if _, err := file.WriteString(newKey + "\n"); err != nil {
+		return fmt.Errorf("could not write to authorized_keys file: %v", err)
+	}
+	return nil
+}
+
+func RemoveKeyFromAuthorizedKeys(path, keyToRemove string) error {
+	keys, err := ReadAuthorizedKeys(path)
+	if err != nil {
+		return err
+	}
+
+	// Check if the key exists in the map
+	if !keys[keyToRemove] {
+		return errors.New("key not found in authorized_keys")
+	}
+
+	// Delete the key from the map
+	delete(keys, keyToRemove)
+
+	// Write updated keys back to the authorized_keys file
+	file, err := os.OpenFile(path, os.O_TRUNC|os.O_WRONLY|os.O_CREATE, 0600)
+	if err != nil {
+		return fmt.Errorf("could not open authorized_keys file for writing: %v", err)
+	}
+	defer file.Close()
+
+	for key := range keys {
+		if _, err := file.WriteString(key + "\n"); err != nil {
+			return fmt.Errorf("could not write to authorized_keys file: %v", err)
+		}
+	}
+
+	return nil
+}
+
+// AddAuthorisationKey Adds public key provided to the
+// authorization file so that nodes can SSH into
+// the
+func AddAuthorisationKey(PublicKey string) error {
+	path, err := GetAuthorizedKeysPath()
+	if err != nil {
+		return err
+	}
+
+	// Display existing keys
+	_, err = ReadAuthorizedKeys(path)
+	if err != nil {
+		return err
+	}
+
+	err = AddKeyToAuthorizedKeys(path, PublicKey)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}