crypto: add QCryptoSecret object class for password/key handling

Introduce a new QCryptoSecret object class which will be used
for providing passwords and keys to other objects which need
sensitive credentials.

The new object can provide secret values directly as properties,
or indirectly via a file. The latter includes support for file
descriptor passing syntax on UNIX platforms. Ordinarily passing
secret values directly as properties is insecure, since they
are visible in process listings, or in log files showing the
CLI args / QMP commands. It is possible to use AES-256-CBC to
encrypt the secret values though, in which case all that is
visible is the ciphertext.  For ad hoc developer testing though,
it is fine to provide the secrets directly without encryption
so this is not explicitly forbidden.

The anticipated scenario is that libvirtd will create a random
master key per QEMU instance (eg /var/run/libvirt/qemu/$VMNAME.key)
and will use that key to encrypt all passwords it provides to
QEMU via '-object secret,....'.  This avoids the need for libvirt
(or other mgmt apps) to worry about file descriptor passing.

It also makes life easier for people who are scripting the
management of QEMU, for whom FD passing is significantly more
complex.

Providing data inline (insecure, only for ad hoc dev testing)

  $QEMU -object secret,id=sec0,data=letmein

Providing data indirectly in raw format

  printf "letmein" > mypasswd.txt
  $QEMU -object secret,id=sec0,file=mypasswd.txt

Providing data indirectly in base64 format

  $QEMU -object secret,id=sec0,file=mykey.b64,format=base64

Providing data with encryption

  $QEMU -object secret,id=master0,file=mykey.b64,format=base64 \
        -object secret,id=sec0,data=[base64 ciphertext],\
	           keyid=master0,iv=[base64 IV],format=base64

Note that 'format' here refers to the format of the ciphertext
data. The decrypted data must always be in raw byte format.

More examples are shown in the updated docs.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

3 files changed, 455 insertions, 0 deletions

diff --git a/tests/.gitignore b/tests/.gitignore
index 596fef3..787c95c 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -14,6 +14,7 @@ test-blockjob-txn
 test-coroutine
 test-crypto-cipher
 test-crypto-hash
+test-crypto-secret
 test-crypto-tlscredsx509
 test-crypto-tlscredsx509-work/
 test-crypto-tlscredsx509-certs/
diff --git a/tests/Makefile b/tests/Makefile
index 3ae57b8..7d2a0d3 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -80,6 +80,7 @@ check-unit-y += tests/test-write-threshold$(EXESUF)
 gcov-files-test-write-threshold-y = block/write-threshold.c
 check-unit-$(CONFIG_GNUTLS_HASH) += tests/test-crypto-hash$(EXESUF)
 check-unit-y += tests/test-crypto-cipher$(EXESUF)
+check-unit-y += tests/test-crypto-secret$(EXESUF)
 check-unit-$(CONFIG_GNUTLS) += tests/test-crypto-tlscredsx509$(EXESUF)
 check-unit-$(CONFIG_GNUTLS) += tests/test-crypto-tlssession$(EXESUF)
 check-unit-$(CONFIG_LINUX) += tests/test-qga$(EXESUF)
@@ -467,6 +468,7 @@ tests/test-mul64$(EXESUF): tests/test-mul64.o $(test-util-obj-y)
 tests/test-bitops$(EXESUF): tests/test-bitops.o $(test-util-obj-y)
 tests/test-crypto-hash$(EXESUF): tests/test-crypto-hash.o $(test-crypto-obj-y)
 tests/test-crypto-cipher$(EXESUF): tests/test-crypto-cipher.o $(test-crypto-obj-y)
+tests/test-crypto-secret$(EXESUF): tests/test-crypto-secret.o $(test-crypto-obj-y)
 
 tests/crypto-tls-x509-helpers.o-cflags := $(TASN1_CFLAGS)
 tests/crypto-tls-x509-helpers.o-libs := $(TASN1_LIBS)
diff --git a/tests/test-crypto-secret.c b/tests/test-crypto-secret.c
new file mode 100644
index 0000000..a49c8e3
--- /dev/null
+++ b/tests/test-crypto-secret.c
@@ -0,0 +1,452 @@
+/*
+ * QEMU Crypto secret handling
+ *
+ * Copyright (c) 2015 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <glib.h>
+
+#include "crypto/init.h"
+#include "crypto/secret.h"
+
+static void test_secret_direct(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data", "123456",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             &error_abort);
+
+    g_assert_cmpstr(pw, ==, "123456");
+
+    object_unparent(sec);
+    g_free(pw);
+}
+
+
+static void test_secret_indirect_good(void)
+{
+    Object *sec;
+    char *fname = NULL;
+    int fd = g_file_open_tmp("secretXXXXXX",
+                             &fname,
+                             NULL);
+
+    g_assert(fd >= 0);
+    g_assert_nonnull(fname);
+
+    g_assert(write(fd, "123456", 6) == 6);
+
+    sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "file", fname,
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             &error_abort);
+
+    g_assert_cmpstr(pw, ==, "123456");
+
+    object_unparent(sec);
+    g_free(pw);
+    close(fd);
+    g_free(fname);
+}
+
+
+static void test_secret_indirect_badfile(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        NULL,
+        "file", "does-not-exist",
+        NULL);
+
+    g_assert(sec == NULL);
+}
+
+
+static void test_secret_indirect_emptyfile(void)
+{
+    Object *sec;
+    char *fname = NULL;
+    int fd = g_file_open_tmp("secretXXXXXX",
+                             &fname,
+                             NULL);
+
+    g_assert(fd >= 0);
+    g_assert_nonnull(fname);
+
+    sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "file", fname,
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             &error_abort);
+
+    g_assert_cmpstr(pw, ==, "");
+
+    object_unparent(sec);
+    g_free(pw);
+    close(fd);
+    g_free(fname);
+}
+
+
+static void test_secret_noconv_base64_good(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data", "MTIzNDU2",
+        "format", "base64",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_base64("sec0",
+                                               &error_abort);
+
+    g_assert_cmpstr(pw, ==, "MTIzNDU2");
+
+    object_unparent(sec);
+    g_free(pw);
+}
+
+
+static void test_secret_noconv_base64_bad(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        NULL,
+        "data", "MTI$NDU2",
+        "format", "base64",
+        NULL);
+
+    g_assert(sec == NULL);
+}
+
+
+static void test_secret_noconv_utf8(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data", "123456",
+        "format", "raw",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             &error_abort);
+
+    g_assert_cmpstr(pw, ==, "123456");
+
+    object_unparent(sec);
+    g_free(pw);
+}
+
+
+static void test_secret_conv_base64_utf8valid(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data", "MTIzNDU2",
+        "format", "base64",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             &error_abort);
+
+    g_assert_cmpstr(pw, ==, "123456");
+
+    object_unparent(sec);
+    g_free(pw);
+}
+
+
+static void test_secret_conv_base64_utf8invalid(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data", "f0VMRgIBAQAAAA==",
+        "format", "base64",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             NULL);
+    g_assert(pw == NULL);
+
+    object_unparent(sec);
+}
+
+
+static void test_secret_conv_utf8_base64(void)
+{
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data", "123456",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_base64("sec0",
+                                               &error_abort);
+
+    g_assert_cmpstr(pw, ==, "MTIzNDU2");
+
+    object_unparent(sec);
+    g_free(pw);
+}
+
+
+static void test_secret_crypt_raw(void)
+{
+    Object *master = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "master",
+        &error_abort,
+        "data", "9miloPQCzGy+TL6aonfzVcptibCmCIhKzrnlfwiWivk=",
+        "format", "base64",
+        NULL);
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data",
+        "\xCC\xBF\xF7\x09\x46\x19\x0B\x52\x2A\x3A\xB4\x6B\xCD\x7A\xB0\xB0",
+        "format", "raw",
+        "keyid", "master",
+        "iv", "0I7Gw/TKuA+Old2W2apQ3g==",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             &error_abort);
+
+    g_assert_cmpstr(pw, ==, "123456");
+
+    object_unparent(sec);
+    object_unparent(master);
+    g_free(pw);
+}
+
+
+static void test_secret_crypt_base64(void)
+{
+    Object *master = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "master",
+        &error_abort,
+        "data", "9miloPQCzGy+TL6aonfzVcptibCmCIhKzrnlfwiWivk=",
+        "format", "base64",
+        NULL);
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        &error_abort,
+        "data", "zL/3CUYZC1IqOrRrzXqwsA==",
+        "format", "base64",
+        "keyid", "master",
+        "iv", "0I7Gw/TKuA+Old2W2apQ3g==",
+        NULL);
+
+    char *pw = qcrypto_secret_lookup_as_utf8("sec0",
+                                             &error_abort);
+
+    g_assert_cmpstr(pw, ==, "123456");
+
+    object_unparent(sec);
+    object_unparent(master);
+    g_free(pw);
+}
+
+
+static void test_secret_crypt_short_key(void)
+{
+    Object *master = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "master",
+        &error_abort,
+        "data", "9miloPQCzGy+TL6aonfzVc",
+        "format", "base64",
+        NULL);
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        NULL,
+        "data", "zL/3CUYZC1IqOrRrzXqwsA==",
+        "format", "raw",
+        "keyid", "master",
+        "iv", "0I7Gw/TKuA+Old2W2apQ3g==",
+        NULL);
+
+    g_assert(sec == NULL);
+    object_unparent(master);
+}
+
+
+static void test_secret_crypt_short_iv(void)
+{
+    Object *master = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "master",
+        &error_abort,
+        "data", "9miloPQCzGy+TL6aonfzVcptibCmCIhKzrnlfwiWivk=",
+        "format", "base64",
+        NULL);
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        NULL,
+        "data", "zL/3CUYZC1IqOrRrzXqwsA==",
+        "format", "raw",
+        "keyid", "master",
+        "iv", "0I7Gw/TKuA+Old2W2a",
+        NULL);
+
+    g_assert(sec == NULL);
+    object_unparent(master);
+}
+
+
+static void test_secret_crypt_missing_iv(void)
+{
+    Object *master = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "master",
+        &error_abort,
+        "data", "9miloPQCzGy+TL6aonfzVcptibCmCIhKzrnlfwiWivk=",
+        "format", "base64",
+        NULL);
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        NULL,
+        "data", "zL/3CUYZC1IqOrRrzXqwsA==",
+        "format", "raw",
+        "keyid", "master",
+        NULL);
+
+    g_assert(sec == NULL);
+    object_unparent(master);
+}
+
+
+static void test_secret_crypt_bad_iv(void)
+{
+    Object *master = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "master",
+        &error_abort,
+        "data", "9miloPQCzGy+TL6aonfzVcptibCmCIhKzrnlfwiWivk=",
+        "format", "base64",
+        NULL);
+    Object *sec = object_new_with_props(
+        TYPE_QCRYPTO_SECRET,
+        object_get_objects_root(),
+        "sec0",
+        NULL,
+        "data", "zL/3CUYZC1IqOrRrzXqwsA==",
+        "format", "raw",
+        "keyid", "master",
+        "iv", "0I7Gw/TK$$uA+Old2W2a",
+        NULL);
+
+    g_assert(sec == NULL);
+    object_unparent(master);
+}
+
+
+int main(int argc, char **argv)
+{
+    module_call_init(MODULE_INIT_QOM);
+    g_test_init(&argc, &argv, NULL);
+
+    g_assert(qcrypto_init(NULL) == 0);
+
+    g_test_add_func("/crypto/secret/direct",
+                    test_secret_direct);
+    g_test_add_func("/crypto/secret/indirect/good",
+                    test_secret_indirect_good);
+    g_test_add_func("/crypto/secret/indirect/badfile",
+                    test_secret_indirect_badfile);
+    g_test_add_func("/crypto/secret/indirect/emptyfile",
+                    test_secret_indirect_emptyfile);
+
+    g_test_add_func("/crypto/secret/noconv/base64/good",
+                    test_secret_noconv_base64_good);
+    g_test_add_func("/crypto/secret/noconv/base64/bad",
+                    test_secret_noconv_base64_bad);
+    g_test_add_func("/crypto/secret/noconv/utf8",
+                    test_secret_noconv_utf8);
+    g_test_add_func("/crypto/secret/conv/base64/utf8valid",
+                    test_secret_conv_base64_utf8valid);
+    g_test_add_func("/crypto/secret/conv/base64/utf8invalid",
+                    test_secret_conv_base64_utf8invalid);
+    g_test_add_func("/crypto/secret/conv/utf8/base64",
+                    test_secret_conv_utf8_base64);
+
+    g_test_add_func("/crypto/secret/crypt/raw",
+                    test_secret_crypt_raw);
+    g_test_add_func("/crypto/secret/crypt/base64",
+                    test_secret_crypt_base64);
+    g_test_add_func("/crypto/secret/crypt/shortkey",
+                    test_secret_crypt_short_key);
+    g_test_add_func("/crypto/secret/crypt/shortiv",
+                    test_secret_crypt_short_iv);
+    g_test_add_func("/crypto/secret/crypt/missingiv",
+                    test_secret_crypt_missing_iv);
+    g_test_add_func("/crypto/secret/crypt/badiv",
+                    test_secret_crypt_bad_iv);
+
+    return g_test_run();
+}