* Add child 'secret' class from basic 'secret_common' with 'data' and 'file' properties.
Signed-off-by: Alexey Krasikov <alex-krasi...@yandex-team.ru> --- crypto/secret.c | 167 ++++++++++++++++++++++++++++++++++++++++ include/crypto/secret.h | 133 ++++++++++++++++++++++++++++++++ 2 files changed, 300 insertions(+) create mode 100644 crypto/secret.c create mode 100644 include/crypto/secret.h diff --git a/crypto/secret.c b/crypto/secret.c new file mode 100644 index 0000000000..d9be0409e4 --- /dev/null +++ b/crypto/secret.c @@ -0,0 +1,167 @@ +/* + * QEMU crypto secret support + * + * 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 2.1 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 "qemu/osdep.h" +#include "crypto/secret.h" +#include "qapi/error.h" +#include "qom/object_interfaces.h" +#include "qemu/module.h" +#include "trace.h" + + +static void +qcrypto_secret_load_data(Object *obj, + uint8_t **output, + size_t *outputlen, + Error **errp) +{ + char *data = NULL; + size_t length = 0; + GError *gerr = NULL; + + QCryptoSecret *secret = QCRYPTO_SECRET(obj); + + *output = NULL; + *outputlen = 0; + + if (secret->file) { + if (secret->data) { + error_setg(errp, + "'file' and 'data' are mutually exclusive"); + return; + } + if (!g_file_get_contents(secret->file, &data, &length, &gerr)) { + error_setg(errp, + "Unable to read %s: %s", + secret->file, gerr->message); + g_error_free(gerr); + return; + } + *output = (uint8_t *)data; + *outputlen = length; + } else if (secret->data) { + *outputlen = strlen(secret->data); + *output = (uint8_t *)g_strdup(secret->data); + } else { + error_setg(errp, "Either 'file' or 'data' must be provided"); + } +} + + +static void +qcrypto_secret_prop_set_data(Object *obj, + const char *value, + Error **errp) +{ + QCryptoSecret *secret = QCRYPTO_SECRET(obj); + + g_free(secret->data); + secret->data = g_strdup(value); +} + + +static char * +qcrypto_secret_prop_get_data(Object *obj, + Error **errp) +{ + QCryptoSecret *secret = QCRYPTO_SECRET(obj); + return g_strdup(secret->data); +} + + +static void +qcrypto_secret_prop_set_file(Object *obj, + const char *value, + Error **errp) +{ + QCryptoSecret *secret = QCRYPTO_SECRET(obj); + + g_free(secret->file); + secret->file = g_strdup(value); +} + + +static char * +qcrypto_secret_prop_get_file(Object *obj, + Error **errp) +{ + QCryptoSecret *secret = QCRYPTO_SECRET(obj); + return g_strdup(secret->file); +} + + +static void +qcrypto_secret_complete(UserCreatable *uc, Error **errp) +{ + object_property_set_bool(OBJECT(uc), true, "loaded", errp); +} + + +static void +qcrypto_secret_finalize(Object *obj) +{ + QCryptoSecret *secret = QCRYPTO_SECRET(obj); + + g_free(secret->file); + g_free(secret->data); +} + +static void +qcrypto_secret_class_init(ObjectClass *oc, void *data) +{ + QCryptoSecretCommonClass *sic = QCRYPTO_SECRET_COMMON_CLASS(oc); + sic->load_data = qcrypto_secret_load_data; + + UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); + ucc->complete = qcrypto_secret_complete; + + object_class_property_add_str(oc, "data", + qcrypto_secret_prop_get_data, + qcrypto_secret_prop_set_data, + NULL); + object_class_property_add_str(oc, "file", + qcrypto_secret_prop_get_file, + qcrypto_secret_prop_set_file, + NULL); +} + + +static const TypeInfo qcrypto_secret_info = { + .parent = TYPE_QCRYPTO_SECRET_COMMON, + .name = TYPE_QCRYPTO_SECRET, + .instance_size = sizeof(QCryptoSecret), + .instance_finalize = qcrypto_secret_finalize, + .class_size = sizeof(QCryptoSecretClass), + .class_init = qcrypto_secret_class_init, + .interfaces = (InterfaceInfo[]) { + { TYPE_USER_CREATABLE }, + { } + } +}; + + +static void +qcrypto_secret_register_types(void) +{ + type_register_static(&qcrypto_secret_info); +} + + +type_init(qcrypto_secret_register_types); diff --git a/include/crypto/secret.h b/include/crypto/secret.h new file mode 100644 index 0000000000..2ce8dcc24f --- /dev/null +++ b/include/crypto/secret.h @@ -0,0 +1,133 @@ +/* + * QEMU crypto secret support + * + * 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 2.1 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/>. + * + */ + +#ifndef QCRYPTO_SECRET_H +#define QCRYPTO_SECRET_H + +#include "qapi/qapi-types-crypto.h" +#include "qom/object.h" +#include "crypto/secret_interface.h" + +#define TYPE_QCRYPTO_SECRET "secret" +#define QCRYPTO_SECRET(obj) \ + OBJECT_CHECK(QCryptoSecret, (obj), TYPE_QCRYPTO_SECRET) + +typedef struct QCryptoSecret QCryptoSecret; +typedef struct QCryptoSecretClass QCryptoSecretClass; + +/** + * QCryptoSecret: + * + * The QCryptoSecret object provides storage of secrets, + * which may be user passwords, encryption keys or any + * other kind of sensitive data that is represented as + * a sequence of bytes. + * + * The sensitive data associated with the secret can + * be provided directly via the 'data' property, or + * indirectly via the 'file' property. In the latter + * case there is support for file descriptor passing + * via the usual /dev/fdset/NN syntax that QEMU uses. + * + * The data for a secret can be provided in two formats, + * either as a UTF-8 string (the default), or as base64 + * encoded 8-bit binary data. The latter is appropriate + * for raw encryption keys, while the former is appropriate + * for user entered passwords. + * + * The data may be optionally encrypted with AES-256-CBC, + * and the decryption key provided by another + * QCryptoSecret instance identified by the 'keyid' + * property. When passing sensitive data directly + * via the 'data' property it is strongly recommended + * to use the AES encryption facility to prevent the + * sensitive data being exposed in the process listing + * or system log files. + * + * Providing data directly, insecurely (suitable for + * ad hoc developer testing only) + * + * $QEMU -object secret,id=sec0,data=letmein + * + * Providing data indirectly: + * + * # printf "letmein" > password.txt + * # $QEMU \ + * -object secret,id=sec0,file=password.txt + * + * Using a master encryption key with data. + * + * The master key needs to be created as 32 secure + * random bytes (optionally base64 encoded) + * + * # openssl rand -base64 32 > key.b64 + * # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') + * + * Each secret to be encrypted needs to have a random + * initialization vector generated. These do not need + * to be kept secret + * + * # openssl rand -base64 16 > iv.b64 + * # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') + * + * A secret to be defined can now be encrypted + * + * # SECRET=$(printf "letmein" | + * openssl enc -aes-256-cbc -a -K $KEY -iv $IV) + * + * When launching QEMU, create a master secret pointing + * to key.b64 and specify that to be used to decrypt + * the user password + * + * # $QEMU \ + * -object secret,id=secmaster0,format=base64,file=key.b64 \ + * -object secret,id=sec0,keyid=secmaster0,format=base64,\ + * data=$SECRET,iv=$(<iv.b64) + * + * When encrypting, the data can still be provided via an + * external file, in which case it is possible to use either + * raw binary data, or base64 encoded. This example uses + * raw format + * + * # printf "letmein" | + * openssl enc -aes-256-cbc -K $KEY -iv $IV -o pw.aes + * # $QEMU \ + * -object secret,id=secmaster0,format=base64,file=key.b64 \ + * -object secret,id=sec0,keyid=secmaster0,\ + * file=pw.aes,iv=$(<iv.b64) + * + * Note that the ciphertext can be in either raw or base64 + * format, as indicated by the 'format' parameter, but the + * plaintext resulting from decryption is expected to always + * be in raw format. + */ + +struct QCryptoSecret { + QCryptoSecretCommon parent_obj; + char *data; + char *file; +}; + + +struct QCryptoSecretClass { + QCryptoSecretCommonClass parent_class; +}; + +#endif /* QCRYPTO_SECRET_H */ -- 2.17.1
