Add "PassphraseKey" classes for code which needs to actually use credentials

Summary: Ref T4122. These classes provide typed, checked access to credentials, so you can say "give me this password, and throw if anything is funky".

Test Plan: Used in next revision.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T4122

Differential Revision: https://secure.phabricator.com/D7625

src/__phutil_library_map__.php

@@ -947,6 +947,7 @@ phutil_register_library_map(array(
     'PackageDeleteMail' => 'applications/owners/mail/PackageDeleteMail.php',
     'PackageMail' => 'applications/owners/mail/PackageMail.php',
     'PackageModifyMail' => 'applications/owners/mail/PackageModifyMail.php',
+    'PassphraseAbstractKey' => 'applications/passphrase/keys/PassphraseAbstractKey.php',
     'PassphraseController' => 'applications/passphrase/controller/PassphraseController.php',
     'PassphraseCredential' => 'applications/passphrase/storage/PassphraseCredential.php',
     'PassphraseCredentialControl' => 'applications/passphrase/view/PassphraseCredentialControl.php',
@@ -968,6 +969,8 @@ phutil_register_library_map(array(
     'PassphraseCredentialViewController' => 'applications/passphrase/controller/PassphraseCredentialViewController.php',
     'PassphraseDAO' => 'applications/passphrase/storage/PassphraseDAO.php',
     'PassphrasePHIDTypeCredential' => 'applications/passphrase/phid/PassphrasePHIDTypeCredential.php',
+    'PassphrasePasswordKey' => 'applications/passphrase/keys/PassphrasePasswordKey.php',
+    'PassphraseSSHKey' => 'applications/passphrase/keys/PassphraseSSHKey.php',
     'PassphraseSecret' => 'applications/passphrase/storage/PassphraseSecret.php',
     'PasteCapabilityDefaultView' => 'applications/paste/capability/PasteCapabilityDefaultView.php',
     'PasteCreateMailReceiver' => 'applications/paste/mail/PasteCreateMailReceiver.php',
@@ -3330,6 +3333,7 @@ phutil_register_library_map(array(
     'PackageDeleteMail' => 'PackageMail',
     'PackageMail' => 'PhabricatorMail',
     'PackageModifyMail' => 'PackageMail',
+    'PassphraseAbstractKey' => 'Phobject',
     'PassphraseController' => 'PhabricatorController',
     'PassphraseCredential' =>
     array(
@@ -3359,6 +3363,8 @@ phutil_register_library_map(array(
     'PassphraseCredentialViewController' => 'PassphraseController',
     'PassphraseDAO' => 'PhabricatorLiskDAO',
     'PassphrasePHIDTypeCredential' => 'PhabricatorPHIDType',
+    'PassphrasePasswordKey' => 'PassphraseAbstractKey',
+    'PassphraseSSHKey' => 'PassphraseAbstractKey',
     'PassphraseSecret' => 'PassphraseDAO',
     'PasteCapabilityDefaultView' => 'PhabricatorPolicyCapability',
     'PasteCreateMailReceiver' => 'PhabricatorMailReceiver',

src/applications/passphrase/credentialtype/PassphraseCredentialTypePassword.php

@@ -3,12 +3,15 @@
 final class PassphraseCredentialTypePassword
   extends PassphraseCredentialType {
 
+  const CREDENTIAL_TYPE = 'password';
+  const PROVIDES_TYPE = 'provides/password';
+
   public function getCredentialType() {
-    return 'password';
+    return self::CREDENTIAL_TYPE;
   }
 
   public function getProvidesType() {
-    return 'provides/password';
+    return self::PROVIDES_TYPE;
   }
 
   public function getCredentialTypeName() {

src/applications/passphrase/credentialtype/PassphraseCredentialTypeSSHPrivateKey.php

@@ -3,8 +3,10 @@
 abstract class PassphraseCredentialTypeSSHPrivateKey
   extends PassphraseCredentialType {
 
+  const PROVIDES_TYPE = 'provides/ssh-key-file';
+
   final public function getProvidesType() {
-    return 'provides/ssh-key-file';
+    return self::PROVIDES_TYPE;
   }
 
 }

src/applications/passphrase/credentialtype/PassphraseCredentialTypeSSHPrivateKeyFile.php

@@ -3,8 +3,10 @@
 final class PassphraseCredentialTypeSSHPrivateKeyFile
   extends PassphraseCredentialTypeSSHPrivateKey {
 
+  const CREDENTIAL_TYPE = 'ssh-key-file';
+
   public function getCredentialType() {
-    return 'ssh-key-file';
+    return self::CREDENTIAL_TYPE;
   }
 
   public function getCredentialTypeName() {

src/applications/passphrase/credentialtype/PassphraseCredentialTypeSSHPrivateKeyText.php

@@ -3,8 +3,10 @@
 final class PassphraseCredentialTypeSSHPrivateKeyText
   extends PassphraseCredentialTypeSSHPrivateKey {
 
+  const CREDENTIAL_TYPE = 'ssh-key-text';
+
   public function getCredentialType() {
-    return 'ssh-key-text';
+    return self::CREDENTIAL_TYPE;
   }
 
   public function getCredentialTypeName() {

src/applications/passphrase/keys/PassphraseAbstractKey.php

@@ -0,0 +1,66 @@
+<?php
+
+abstract class PassphraseAbstractKey extends Phobject {
+
+  private $credential;
+
+  protected function requireCredential() {
+    if (!$this->credential) {
+      throw new Exception(pht("Credential is required!"));
+    }
+    return $this->credential;
+  }
+
+  private function loadCredential(
+    $phid,
+    PhabricatorUser $viewer) {
+
+    $credential = id(new PassphraseCredentialQuery())
+      ->setViewer($viewer)
+      ->withPHIDs(array($phid))
+      ->needSecrets(true)
+      ->executeOne();
+
+    if (!$credential) {
+      throw new Exception(pht('Failed to load credential "%s"!', $phid));
+    }
+
+    return $credential;
+  }
+
+  private function validateCredential(
+    PassphraseCredential $credential,
+    $provides_type) {
+
+    $type = $credential->getCredentialType();
+    if ($type->getProvides() !== $provides_type) {
+      throw new Exception(
+        pht(
+          'Credential "%s" must provide "%s", but provides "%s"!',
+          'K'.$credential->getID(),
+          $provides_type,
+          $type->getProvides()));
+    }
+
+  }
+
+  protected function loadAndValidateFromPHID(
+    $phid,
+    PhabricatorUser $viewer,
+    $type) {
+
+    $credential = $this->loadCredential($phid, $viewer);
+
+    $this->validateCredential($credential, $type);
+
+    $this->credential = $credential;
+
+    return $this;
+  }
+
+  public function getUsernameEnvelope() {
+    $credential = $this->requireCredential();
+    return new PhutilOpaqueEnvelope($credential->getUsername());
+  }
+
+}

src/applications/passphrase/keys/PassphrasePasswordKey.php

@@ -0,0 +1,17 @@
+<?php
+
+final class PassphrasePasswordKey extends PassphraseAbstractKey {
+
+  public static function loadFromPHID($phid, PhabricatorUser $viewer) {
+    $key = new PassphraseSSHKey();
+    return $key->loadAndValidateFromPHID(
+      $phid,
+      $viewer,
+      PassphraseCredentialTypePassword::PROVIDES_TYPE);
+  }
+
+  public function getPasswordEnvelope() {
+    return $this->requireCredential()->getSecret();
+  }
+
+}

src/applications/passphrase/keys/PassphraseSSHKey.php

@@ -0,0 +1,40 @@
+<?php
+
+final class PassphraseSSHKey extends PassphraseAbstractKey {
+
+  private $keyFile;
+
+  public static function loadFromPHID($phid, PhabricatorUser $viewer) {
+    $key = new PassphraseSSHKey();
+    return $key->loadAndValidateFromPHID(
+      $phid,
+      $viewer,
+      PassphraseCredentialTypeSSHPrivateKey::PROVIDES_TYPE);
+  }
+
+  public function getKeyfileEnvelope() {
+    $credential = $this->requireCredential();
+
+    $text_type = PassphraseCredentialTypeSSHPrivateKeyText::CREDENTIAL_TYPE;
+    if ($credential->getCredentialType() == $text_type) {
+      // If the credential stores key text, write it out to a temporary file
+      // so we can pass it to `ssh`.
+      if (!$this->keyFile) {
+        $temporary_file = new TempFile('passphrase-ssh-key');
+
+        Filesystem::changePermissions($temporary_file, 0600);
+
+        Filesystem::writeFile(
+          $temporary_file,
+          $credential->getSecret()->openEnvelope());
+
+        $this->keyFile = $temporary_file;
+      }
+
+      return new PhutilOpaqueEnvelope((string)$this->keyFile);
+    }
+
+    return $credential->getSecret();
+  }
+
+}