* Add the ability for the secret object to obtain secret data from the Linux in-kernel key managment and retention facility, as an extra option to the existing ones: reading from a file or passing directly as a string.
The secret is identified by the key serial number. The upper layers need to instantiate the key and make sure the QEMU process has access rights to read it. Signed-off-by: Alexey Krasikov <alex-krasi...@yandex-team.ru> --- crypto/Makefile.objs | 1 + crypto/linux_keyring.c | 140 +++++++++++++++++++++++++++++++++ include/crypto/linux_keyring.h | 38 +++++++++ 3 files changed, 179 insertions(+) create mode 100644 crypto/linux_keyring.c create mode 100644 include/crypto/linux_keyring.h diff --git a/crypto/Makefile.objs b/crypto/Makefile.objs index 3ae0dfd1a4..7fc354a8d5 100644 --- a/crypto/Makefile.objs +++ b/crypto/Makefile.objs @@ -19,6 +19,7 @@ crypto-obj-y += tlscredspsk.o crypto-obj-y += tlscredsx509.o crypto-obj-y += tlssession.o crypto-obj-y += secret_interface.o +crypto-obj-y += linux_keyring.o crypto-obj-y += secret.o crypto-obj-y += pbkdf.o crypto-obj-$(CONFIG_NETTLE) += pbkdf-nettle.o diff --git a/crypto/linux_keyring.c b/crypto/linux_keyring.c new file mode 100644 index 0000000000..7950d4c12d --- /dev/null +++ b/crypto/linux_keyring.c @@ -0,0 +1,140 @@ +#ifdef __NR_keyctl + +#include "qemu/osdep.h" +#include <asm/unistd.h> +#include <linux/keyctl.h> +#include "qapi/error.h" +#include "qom/object_interfaces.h" +#include "trace.h" +#include "crypto/linux_keyring.h" + + +static inline +long keyctl_read(key_serial_t key, uint8_t *buffer, size_t buflen) +{ + return syscall(__NR_keyctl, KEYCTL_READ, key, buffer, buflen, 0); +} + + +static +long keyctl_read_alloc(key_serial_t key, uint8_t **buffer) +{ + uint8_t *loc_buf; + long retcode = keyctl_read(key, NULL, 0); + if (retcode <= 0) { + return retcode; + } + loc_buf = g_malloc(retcode); + retcode = keyctl_read(key, loc_buf, retcode); + + if (retcode >= 0) { + *buffer = loc_buf; + } else { + g_free(loc_buf); + } + return retcode; +} + + +static void +qcrypto_secret_linux_load_data(Object *obj, + uint8_t **output, + size_t *outputlen, + Error **errp) +{ + QCryptoSecretLinuxKeyring *secret = QCRYPTO_SECRET_LINUX_KEYRING(obj); + uint8_t *buffer = NULL; + long retcode; + + *output = NULL; + *outputlen = 0; + + if (secret->serial) { + retcode = keyctl_read_alloc(secret->serial, &buffer); + if (retcode < 0) { + error_setg_errno(errp, errno, + "Unable to read serial key %08x", + secret->serial); + return; + } else { + *outputlen = retcode; + *output = buffer; + } + } else { + error_setg(errp, "Either 'serial' must be provided"); + } +} + + +static void +qcrypto_secret_prop_set_key(Object *obj, Visitor *v, + const char *name, void *opaque, + Error **errp) +{ + QCryptoSecretLinuxKeyring *secret = QCRYPTO_SECRET_LINUX_KEYRING(obj); + int32_t value; + visit_type_int32(v, name, &value, errp); + if (!value) { + error_setg(errp, "The 'serial' should be not equal 0"); + } + secret->serial = value; +} + + +static void +qcrypto_secret_prop_get_key(Object *obj, Visitor *v, + const char *name, void *opaque, + Error **errp) +{ + QCryptoSecretLinuxKeyring *secret = QCRYPTO_SECRET_LINUX_KEYRING(obj); + int32_t value = secret->serial; + visit_type_int32(v, name, &value, errp); +} + + +static void +qcrypto_secret_linux_complete(UserCreatable *uc, Error **errp) +{ + object_property_set_bool(OBJECT(uc), true, "loaded", errp); +} + + +static void +qcrypto_secret_linux_class_init(ObjectClass *oc, void *data) +{ + QCryptoSecretCommonClass *sic = QCRYPTO_SECRET_COMMON_CLASS(oc); + sic->load_data = qcrypto_secret_linux_load_data; + + UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); + ucc->complete = qcrypto_secret_linux_complete; + + object_class_property_add(oc, "serial", "key_serial_t", + qcrypto_secret_prop_get_key, + qcrypto_secret_prop_set_key, + NULL, NULL, NULL); +} + + +static const TypeInfo qcrypto_secret_info = { + .parent = TYPE_QCRYPTO_SECRET_COMMON, + .name = TYPE_QCRYPTO_SECRET_LINUX_KEYRING, + .instance_size = sizeof(QCryptoSecretLinuxKeyring), + .class_size = sizeof(QCryptoSecretLinuxKeyringClass), + .class_init = qcrypto_secret_linux_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); + +#endif /* __NR_keyctl */ diff --git a/include/crypto/linux_keyring.h b/include/crypto/linux_keyring.h new file mode 100644 index 0000000000..2618b34444 --- /dev/null +++ b/include/crypto/linux_keyring.h @@ -0,0 +1,38 @@ +#ifndef QCRYPTO_SECRET_LINUX_KEYRING_H +#define QCRYPTO_SECRET_LINUX_KEYRING_H + +#ifdef __NR_keyctl + +#include "qapi/qapi-types-crypto.h" +#include "qom/object.h" +#include "crypto/secret_interface.h" + +#define TYPE_QCRYPTO_SECRET_LINUX_KEYRING "syskey" +#define QCRYPTO_SECRET_LINUX_KEYRING(obj) \ + OBJECT_CHECK(QCryptoSecretLinuxKeyring, (obj), \ + TYPE_QCRYPTO_SECRET_LINUX_KEYRING) +#define QCRYPTO_SECRET_LINUX_KEYRING_CLASS(class) \ + OBJECT_CLASS_CHECK(QCryptoSecretLinuxKeyringClass, \ + (class), TYPE_QCRYPTO_SECRET_LINUX_KEYRING) +#define QCRYPTO_SECRET_LINUX_KEYRING_GET_CLASS(class) \ + OBJECT_GET_CLASS(QCryptoSecretLinuxKeyringClass, \ + (class), TYPE_QCRYPTO_SECRET_LINUX_KEYRING) + +typedef struct QCryptoSecretLinux QCryptoSecretLinux; +typedef struct QCryptoSecretLinuxClass QCryptoSecretLinuxClass; + +typedef int32_t key_serial_t; + +typedef struct QCryptoSecretLinuxKeyring { + QCryptoSecretCommon parent; + key_serial_t serial; +} QCryptoSecretLinuxKeyring; + + +typedef struct QCryptoSecretLinuxKeyringClass { + QCryptoSecretCommonClass parent; +} QCryptoSecretLinuxKeyringClass; + +#endif /* __NR_keyctl */ + +#endif /* QCRYPTO_SECRET_LINUX_KEYRING_H */ -- 2.17.1