Added symmetric and asymmetric vaults.

The vault plugin has been modified to support symmetric and asymmetric
vaults to provide additional security over the standard vault by
encrypting the data before it's sent to the server. The encryption
functionality is implemented using the python-cryptography library.

https://fedorahosted.org/freeipa/ticket/3872

Reviewed-By: Jan Cholasta <jcholast@redhat.com>

1 files changed, 548 insertions, 35 deletions

diff --git a/ipalib/plugins/vault.py b/ipalib/plugins/vault.py
index f80ecfdfa..193fa5cbb 100644
--- a/ipalib/plugins/vault.py
+++ b/ipalib/plugins/vault.py
@@ -18,11 +18,20 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import base64
+import getpass
 import json
 import os
 import sys
 import tempfile
 
+from cryptography.fernet import Fernet, InvalidToken
+from cryptography.hazmat.backends import default_backend
+from cryptography.hazmat.primitives import hashes
+from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
+from cryptography.hazmat.primitives.asymmetric import padding
+from cryptography.hazmat.primitives.serialization import load_pem_public_key,\
+    load_pem_private_key
+
 import nss.nss as nss
 import krbV
 
@@ -50,6 +59,36 @@ Vaults
 """) + _("""
 Manage vaults.
 """) + _("""
+Vault is a secure place to store a secret.
+""") + _("""
+Based on the ownership there are three vault categories:
+* user/private vault
+* service vault
+* shared vault
+""") + _("""
+User vaults are vaults owned used by a particular user. Private
+vaults are vaults owned the current user. Service vaults are
+vaults owned by a service. Shared vaults are owned by the admin
+but they can be used by other users or services.
+""") + _("""
+Based on the security mechanism there are three types of
+vaults:
+* standard vault
+* symmetric vault
+* asymmetric vault
+""") + _("""
+Standard vault uses a secure mechanism to transport and
+store the secret. The secret can only be retrieved by users
+that have access to the vault.
+""") + _("""
+Symmetric vault is similar to the standard vault, but it
+pre-encrypts the secret using a password before transport.
+The secret can only be retrieved using the same password.
+""") + _("""
+Asymmetric vault is similar to the standard vault, but it
+pre-encrypts the secret using a public key before transport.
+The secret can only be retrieved using the private key.
+""") + _("""
 EXAMPLES:
 """) + _("""
  List private vaults:
@@ -76,6 +115,12 @@ EXAMPLES:
  Add a user vault:
    ipa vault-add <name> --user <username>
 """) + _("""
+ Add a symmetric vault:
+   ipa vault-add <name> --type symmetric --password-file password.txt
+""") + _("""
+ Add an asymmetric vault:
+   ipa vault-add <name> --type asymmetric --public-key-file public.pem
+""") + _("""
  Show a private vault:
    ipa vault-show <name>
 """) + _("""
@@ -113,7 +158,7 @@ EXAMPLES:
    ipa vault-del <name> --user <username>
 """) + _("""
  Display vault configuration:
-   ipa vault-config
+   ipa vaultconfig-show
 """) + _("""
  Archive data into private vault:
    ipa vault-archive <name> --in <input file>
@@ -127,6 +172,12 @@ EXAMPLES:
  Archive data into user vault:
    ipa vault-archive <name> --user <username> --in <input file>
 """) + _("""
+ Archive data into symmetric vault:
+   ipa vault-archive <name> --in <input file>
+""") + _("""
+ Archive data into asymmetric vault:
+   ipa vault-archive <name> --in <input file>
+""") + _("""
  Retrieve data from private vault:
    ipa vault-retrieve <name> --out <output file>
 """) + _("""
@@ -137,7 +188,13 @@ EXAMPLES:
    ipa vault-retrieve <name> --shared --out <output file>
 """) + _("""
  Retrieve data from user vault:
-   ipa vault-retrieve <name> --user <user name> --out <output file>
+   ipa vault-retrieve <name> --user <username> --out <output file>
+""") + _("""
+ Retrieve data from symmetric vault:
+   ipa vault-retrieve <name> --out data.bin
+""") + _("""
+ Retrieve data from asymmetric vault:
+   ipa vault-retrieve <name> --out data.bin --private-key-file private.pem
 """)
 
 register = Registry()
@@ -146,7 +203,7 @@ register = Registry()
 vault_options = (
     Str(
         'service?',
-        doc=_('Service name'),
+        doc=_('Service name of the service vault'),
     ),
     Flag(
         'shared?',
@@ -154,7 +211,7 @@ vault_options = (
     ),
     Str(
         'user?',
-        doc=_('Username'),
+        doc=_('Username of the user vault'),
     ),
 )
 
@@ -174,6 +231,14 @@ class vault(LDAPObject):
     default_attributes = [
         'cn',
         'description',
+        'ipavaulttype',
+        'ipavaultsalt',
+        'ipapublickey',
+    ]
+    search_display_attributes = [
+        'cn',
+        'description',
+        'ipavaulttype',
     ]
 
     label = _('Vaults')
@@ -195,6 +260,28 @@ class vault(LDAPObject):
             label=_('Description'),
             doc=_('Vault description'),
         ),
+        Str(
+            'ipavaulttype?',
+            cli_name='type',
+            label=_('Type'),
+            doc=_('Vault type'),
+            default=u'standard',
+            autofill=True,
+        ),
+        Bytes(
+            'ipavaultsalt?',
+            cli_name='salt',
+            label=_('Salt'),
+            doc=_('Vault salt'),
+            flags=['no_search'],
+        ),
+        Bytes(
+            'ipapublickey?',
+            cli_name='public_key',
+            label=_('Public key'),
+            doc=_('Vault public key'),
+            flags=['no_search'],
+        ),
     )
 
     def get_dn(self, *keys, **options):
@@ -307,12 +394,232 @@ class vault(LDAPObject):
 
         return 'ipa:' + id
 
+    def get_new_password(self):
+        """
+        Gets new password from user and verify it.
+        """
+        while True:
+            password = getpass.getpass('New password: ').decode(
+                sys.stdin.encoding)
+            password2 = getpass.getpass('Verify password: ').decode(
+                sys.stdin.encoding)
+
+            if password == password2:
+                return password
+
+            print '  ** Passwords do not match! **'
+
+    def get_existing_password(self, new=False):
+        """
+        Gets existing password from user.
+        """
+        return getpass.getpass('Password: ').decode(sys.stdin.encoding)
+
+    def generate_symmetric_key(self, password, salt):
+        """
+        Generates symmetric key from password and salt.
+        """
+        kdf = PBKDF2HMAC(
+            algorithm=hashes.SHA256(),
+            length=32,
+            salt=salt,
+            iterations=100000,
+            backend=default_backend()
+        )
+
+        return base64.b64encode(kdf.derive(password.encode('utf-8')))
+
+    def encrypt(self, data, symmetric_key=None, public_key=None):
+        """
+        Encrypts data with symmetric key or public key.
+        """
+        if symmetric_key:
+            fernet = Fernet(symmetric_key)
+            return fernet.encrypt(data)
+
+        elif public_key:
+            rsa_public_key = load_pem_public_key(
+                data=public_key,
+                backend=default_backend()
+            )
+            return rsa_public_key.encrypt(
+                data,
+                padding.OAEP(
+                    mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                    algorithm=hashes.SHA1(),
+                    label=None
+                )
+            )
+
+    def decrypt(self, data, symmetric_key=None, private_key=None):
+        """
+        Decrypts data with symmetric key or public key.
+        """
+        if symmetric_key:
+            try:
+                fernet = Fernet(symmetric_key)
+                return fernet.decrypt(data)
+            except InvalidToken:
+                raise errors.AuthenticationError(
+                    message=_('Invalid credentials'))
+
+        elif private_key:
+            try:
+                rsa_private_key = load_pem_private_key(
+                    data=private_key,
+                    password=None,
+                    backend=default_backend()
+                )
+                return rsa_private_key.decrypt(
+                    data,
+                    padding.OAEP(
+                        mgf=padding.MGF1(algorithm=hashes.SHA1()),
+                        algorithm=hashes.SHA1(),
+                        label=None
+                    )
+                )
+            except AssertionError:
+                raise errors.AuthenticationError(
+                    message=_('Invalid credentials'))
+
 
 @register()
-class vault_add(LDAPCreate):
+class vault_add(PKQuery, Local):
     __doc__ = _('Create a new vault.')
 
-    takes_options = LDAPCreate.takes_options + vault_options
+    takes_options = LDAPCreate.takes_options + vault_options + (
+        Str(
+            'description?',
+            cli_name='desc',
+            doc=_('Vault description'),
+        ),
+        Str(
+            'ipavaulttype?',
+            cli_name='type',
+            doc=_('Vault type'),
+        ),
+        Str(
+            'password?',
+            cli_name='password',
+            doc=_('Vault password'),
+        ),
+        Str(  # TODO: use File parameter
+            'password_file?',
+            cli_name='password_file',
+            doc=_('File containing the vault password'),
+        ),
+        Bytes(
+            'ipapublickey?',
+            cli_name='public_key',
+            doc=_('Vault public key'),
+        ),
+        Str(  # TODO: use File parameter
+            'public_key_file?',
+            cli_name='public_key_file',
+            doc=_('File containing the vault public key'),
+        ),
+    )
+
+    has_output = output.standard_entry
+
+    def forward(self, *args, **options):
+
+        vault_type = options.get('ipavaulttype', u'standard')
+        password = options.get('password')
+        password_file = options.get('password_file')
+        public_key = options.get('ipapublickey')
+        public_key_file = options.get('public_key_file')
+
+        # don't send these parameters to server
+        if 'password' in options:
+            del options['password']
+        if 'password_file' in options:
+            del options['password_file']
+        if 'public_key_file' in options:
+            del options['public_key_file']
+
+        if self.api.env.in_server:
+            backend = self.api.Backend.ldap2
+        else:
+            backend = self.api.Backend.rpcclient
+        if not backend.isconnected():
+            backend.connect(ccache=krbV.default_context().default_ccache())
+
+        if vault_type == u'standard':
+
+            pass
+
+        elif vault_type == u'symmetric':
+
+            # get password
+            if password and password_file:
+                raise errors.MutuallyExclusiveError(
+                    reason=_('Password specified multiple times'))
+
+            elif password:
+                pass
+
+            elif password_file:
+                with open(password_file, 'rb') as f:
+                    password = f.read().rstrip('\n').decode('utf-8')
+
+            else:
+                password = self.obj.get_new_password()
+
+            # generate vault salt
+            options['ipavaultsalt'] = os.urandom(16)
+
+        elif vault_type == u'asymmetric':
+
+            # get new vault public key
+            if public_key and public_key_file:
+                raise errors.MutuallyExclusiveError(
+                    reason=_('Public key specified multiple times'))
+
+            elif public_key:
+                pass
+
+            elif public_key_file:
+                with open(public_key_file, 'rb') as f:
+                    public_key = f.read()
+
+                # store vault public key
+                options['ipapublickey'] = public_key
+
+            else:
+                raise errors.ValidationError(
+                    name='ipapublickey',
+                    error=_('Missing vault public key'))
+
+        # create vault
+        response = self.api.Command.vault_add_internal(*args, **options)
+
+        # prepare parameters for archival
+        opts = options.copy()
+        if 'description' in opts:
+            del opts['description']
+        if 'ipavaulttype' in opts:
+            del opts['ipavaulttype']
+
+        if vault_type == u'symmetric':
+            opts['password'] = password
+            del opts['ipavaultsalt']
+
+        elif vault_type == u'asymmetric':
+            del opts['ipapublickey']
+
+        # archive blank data
+        self.api.Command.vault_archive(*args, **opts)
+
+        return response
+
+
+@register()
+class vault_add_internal(LDAPCreate):
+
+    NO_CLI = True
+
+    takes_options = vault_options
 
     msg_summary = _('Added vault "%(value)s"')
 
@@ -513,29 +820,46 @@ class vault_archive(PKQuery, Local):
             'in?',
             doc=_('File containing data to archive'),
         ),
+        Str(
+            'password?',
+            cli_name='password',
+            doc=_('Vault password'),
+        ),
+        Str(  # TODO: use File parameter
+            'password_file?',
+            cli_name='password_file',
+            doc=_('File containing the vault password'),
+        ),
     )
 
     has_output = output.standard_entry
 
-    msg_summary = _('Archived data into vault "%(value)s"')
-
     def forward(self, *args, **options):
 
+        name = args[-1]
+
         data = options.get('data')
         input_file = options.get('in')
 
+        password = options.get('password')
+        password_file = options.get('password_file')
+
         # don't send these parameters to server
         if 'data' in options:
             del options['data']
         if 'in' in options:
             del options['in']
+        if 'password' in options:
+            del options['password']
+        if 'password_file' in options:
+            del options['password_file']
 
         # get data
         if data and input_file:
             raise errors.MutuallyExclusiveError(
                 reason=_('Input data specified multiple times'))
 
-        if input_file:
+        elif input_file:
             with open(input_file, 'rb') as f:
                 data = f.read()
 
@@ -549,13 +873,77 @@ class vault_archive(PKQuery, Local):
         if not backend.isconnected():
             backend.connect(ccache=krbV.default_context().default_ccache())
 
+        # retrieve vault info
+        vault = self.api.Command.vault_show(*args, **options)['result']
+
+        vault_type = vault['ipavaulttype'][0]
+
+        if vault_type == u'standard':
+
+            encrypted_key = None
+
+        elif vault_type == u'symmetric':
+
+            # get password
+            if password and password_file:
+                raise errors.MutuallyExclusiveError(
+                    reason=_('Password specified multiple times'))
+
+            elif password:
+                pass
+
+            elif password_file:
+                with open(password_file) as f:
+                    password = f.read().rstrip('\n').decode('utf-8')
+
+            else:
+                password = self.obj.get_existing_password()
+
+            # verify password by retrieving existing data
+            opts = options.copy()
+            opts['password'] = password
+            try:
+                self.api.Command.vault_retrieve(*args, **opts)
+            except errors.NotFound:
+                pass
+
+            salt = vault['ipavaultsalt'][0]
+
+            # generate encryption key from vault password
+            encryption_key = self.obj.generate_symmetric_key(
+                password, salt)
+
+            # encrypt data with encryption key
+            data = self.obj.encrypt(data, symmetric_key=encryption_key)
+
+            encrypted_key = None
+
+        elif vault_type == u'asymmetric':
+
+            public_key = vault['ipapublickey'][0].encode('utf-8')
+
+            # generate encryption key
+            encryption_key = base64.b64encode(os.urandom(32))
+
+            # encrypt data with encryption key
+            data = self.obj.encrypt(data, symmetric_key=encryption_key)
+
+            # encrypt encryption key with public key
+            encrypted_key = self.obj.encrypt(
+                encryption_key, public_key=public_key)
+
+        else:
+            raise errors.ValidationError(
+                name='vault_type',
+                error=_('Invalid vault type'))
+
         # initialize NSS database
         current_dbdir = paths.IPA_NSSDB_DIR
         nss.nss_init(current_dbdir)
 
         # retrieve transport certificate
-        config = self.api.Command.vaultconfig_show()
-        transport_cert_der = config['result']['transport_cert']
+        config = self.api.Command.vaultconfig_show()['result']
+        transport_cert_der = config['transport_cert']
         nss_transport_cert = nss.Certificate(transport_cert_der)
 
         # generate session key
@@ -579,6 +967,10 @@ class vault_archive(PKQuery, Local):
         vault_data = {}
         vault_data[u'data'] = base64.b64encode(data).decode('utf-8')
 
+        if encrypted_key:
+            vault_data[u'encrypted_key'] = base64.b64encode(encrypted_key)\
+                .decode('utf-8')
+
         json_vault_data = json.dumps(vault_data)
 
         # wrap vault_data with session key
@@ -595,16 +987,12 @@ class vault_archive(PKQuery, Local):
 
         options['vault_data'] = wrapped_vault_data
 
-        response = self.api.Command.vault_archive_encrypted(*args, **options)
-
-        response['result'] = {}
-        del response['summary']
-
-        return response
+        return self.api.Command.vault_archive_internal(*args, **options)
 
 
 @register()
-class vault_archive_encrypted(Update):
+class vault_archive_internal(PKQuery):
+
     NO_CLI = True
 
     takes_options = vault_options + (
@@ -622,6 +1010,10 @@ class vault_archive_encrypted(Update):
         ),
     )
 
+    has_output = output.standard_entry
+
+    msg_summary = _('Archived data into vault "%(value)s"')
+
     def execute(self, *args, **options):
 
         if not self.api.Command.kra_is_enabled()['result']:
@@ -633,8 +1025,7 @@ class vault_archive_encrypted(Update):
         wrapped_session_key = options.pop('session_key')
 
         # retrieve vault info
-        result = self.api.Command.vault_show(*args, **options)
-        vault = result['result']
+        vault = self.api.Command.vault_show(*args, **options)['result']
 
         # connect to KRA
         kra_client = self.api.Backend.kra.get_client()
@@ -666,7 +1057,14 @@ class vault_archive_encrypted(Update):
 
         kra_account.logout()
 
-        return result
+        response = {
+            'value': args[-1],
+            'result': {},
+        }
+
+        response['summary'] = self.msg_summary % response
+
+        return response
 
 
 @register()
@@ -678,6 +1076,26 @@ class vault_retrieve(PKQuery, Local):
             'out?',
             doc=_('File to store retrieved data'),
         ),
+        Str(
+            'password?',
+            cli_name='password',
+            doc=_('Vault password'),
+        ),
+        Str(  # TODO: use File parameter
+            'password_file?',
+            cli_name='password_file',
+            doc=_('File containing the vault password'),
+        ),
+        Bytes(
+            'private_key?',
+            cli_name='private_key',
+            doc=_('Vault private key'),
+        ),
+        Str(  # TODO: use File parameter
+            'private_key_file?',
+            cli_name='private_key_file',
+            doc=_('File containing the vault private key'),
+        ),
     )
 
     has_output = output.standard_entry
@@ -688,15 +1106,28 @@ class vault_retrieve(PKQuery, Local):
         ),
     )
 
-    msg_summary = _('Retrieved data from vault "%(value)s"')
-
     def forward(self, *args, **options):
 
+        name = args[-1]
+
         output_file = options.get('out')
 
+        password = options.get('password')
+        password_file = options.get('password_file')
+        private_key = options.get('private_key')
+        private_key_file = options.get('private_key_file')
+
         # don't send these parameters to server
         if 'out' in options:
             del options['out']
+        if 'password' in options:
+            del options['password']
+        if 'password_file' in options:
+            del options['password_file']
+        if 'private_key' in options:
+            del options['private_key']
+        if 'private_key_file' in options:
+            del options['private_key_file']
 
         if self.api.env.in_server:
             backend = self.api.Backend.ldap2
@@ -705,13 +1136,18 @@ class vault_retrieve(PKQuery, Local):
         if not backend.isconnected():
             backend.connect(ccache=krbV.default_context().default_ccache())
 
+        # retrieve vault info
+        vault = self.api.Command.vault_show(*args, **options)['result']
+
+        vault_type = vault['ipavaulttype'][0]
+
         # initialize NSS database
         current_dbdir = paths.IPA_NSSDB_DIR
         nss.nss_init(current_dbdir)
 
         # retrieve transport certificate
-        config = self.api.Command.vaultconfig_show()
-        transport_cert_der = config['result']['transport_cert']
+        config = self.api.Command.vaultconfig_show()['result']
+        transport_cert_der = config['transport_cert']
         nss_transport_cert = nss.Certificate(transport_cert_der)
 
         # generate session key
@@ -729,7 +1165,7 @@ class vault_retrieve(PKQuery, Local):
         # send retrieval request to server
         options['session_key'] = wrapped_session_key.data
 
-        response = self.api.Command.vault_retrieve_encrypted(*args, **options)
+        response = self.api.Command.vault_retrieve_internal(*args, **options)
 
         result = response['result']
         nonce = result['nonce']
@@ -751,18 +1187,85 @@ class vault_retrieve(PKQuery, Local):
         vault_data = json.loads(json_vault_data)
         data = base64.b64decode(vault_data[u'data'].encode('utf-8'))
 
+        encrypted_key = None
+
+        if 'encrypted_key' in vault_data:
+            encrypted_key = base64.b64decode(vault_data[u'encrypted_key']
+                                             .encode('utf-8'))
+
+        if vault_type == u'standard':
+
+            pass
+
+        elif vault_type == u'symmetric':
+
+            salt = vault['ipavaultsalt'][0]
+
+            # get encryption key from vault password
+            if password and password_file:
+                raise errors.MutuallyExclusiveError(
+                    reason=_('Password specified multiple times'))
+
+            elif password:
+                pass
+
+            elif password_file:
+                with open(password_file) as f:
+                    password = f.read().rstrip('\n').decode('utf-8')
+
+            else:
+                password = self.obj.get_existing_password()
+
+            # generate encryption key from password
+            encryption_key = self.obj.generate_symmetric_key(password, salt)
+
+            # decrypt data with encryption key
+            data = self.obj.decrypt(data, symmetric_key=encryption_key)
+
+        elif vault_type == u'asymmetric':
+
+            # get encryption key with vault private key
+            if private_key and private_key_file:
+                raise errors.MutuallyExclusiveError(
+                    reason=_('Private key specified multiple times'))
+
+            elif private_key:
+                pass
+
+            elif private_key_file:
+                with open(private_key_file, 'rb') as f:
+                    private_key = f.read()
+
+            else:
+                raise errors.ValidationError(
+                    name='private_key',
+                    error=_('Missing vault private key'))
+
+            # decrypt encryption key with private key
+            encryption_key = self.obj.decrypt(
+                encrypted_key, private_key=private_key)
+
+            # decrypt data with encryption key
+            data = self.obj.decrypt(data, symmetric_key=encryption_key)
+
+        else:
+            raise errors.ValidationError(
+                name='vault_type',
+                error=_('Invalid vault type'))
+
         if output_file:
             with open(output_file, 'w') as f:
                 f.write(data)
 
-        response['result'] = {'data': data}
-        del response['summary']
+        else:
+            response['result'] = {'data': data}
 
         return response
 
 
 @register()
-class vault_retrieve_encrypted(Retrieve):
+class vault_retrieve_internal(PKQuery):
+
     NO_CLI = True
 
     takes_options = vault_options + (
@@ -772,6 +1275,10 @@ class vault_retrieve_encrypted(Retrieve):
         ),
     )
 
+    has_output = output.standard_entry
+
+    msg_summary = _('Retrieved data from vault "%(value)s"')
+
     def execute(self, *args, **options):
 
         if not self.api.Command.kra_is_enabled()['result']:
@@ -781,8 +1288,7 @@ class vault_retrieve_encrypted(Retrieve):
         wrapped_session_key = options.pop('session_key')
 
         # retrieve vault info
-        result = self.api.Command.vault_show(*args, **options)
-        vault = result['result']
+        vault = self.api.Command.vault_show(*args, **options)['result']
 
         # connect to KRA
         kra_client = self.api.Backend.kra.get_client()
@@ -807,12 +1313,19 @@ class vault_retrieve_encrypted(Retrieve):
             key_info.get_key_id(),
             wrapped_session_key)
 
-        vault['vault_data'] = key.encrypted_data
-        vault['nonce'] = key.nonce_data
-
         kra_account.logout()
 
-        return result
+        response = {
+            'value': args[-1],
+            'result': {
+                'vault_data': key.encrypted_data,
+                'nonce': key.nonce_data,
+            },
+        }
+
+        response['summary'] = self.msg_summary % response
+
+        return response
 
 
 @register()