crypto/secret.c | 88 +++++++++++++++++++++++++++++++++++++++-- include/crypto/secret.h | 3 ++ 2 files changed, 88 insertions(+), 3 deletions(-)
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-krasikov@yandex-team.ru>
---
crypto/secret.c | 88 +++++++++++++++++++++++++++++++++++++++--
include/crypto/secret.h | 3 ++
2 files changed, 88 insertions(+), 3 deletions(-)
diff --git a/crypto/secret.c b/crypto/secret.c
index 1cf0ad0ce8..2e8be6241c 100644
--- a/crypto/secret.c
+++ b/crypto/secret.c
@@ -19,6 +19,8 @@
*/
#include "qemu/osdep.h"
+#include <asm/unistd.h>
+#include <linux/keyctl.h>
#include "crypto/secret.h"
#include "crypto/cipher.h"
#include "qapi/error.h"
@@ -28,6 +30,40 @@
#include "trace.h"
+static inline
+long keyctl_read(key_serial_t key, uint8_t *buffer, size_t buflen)
+{
+#ifdef __NR_keyctl
+ return syscall(__NR_keyctl, KEYCTL_READ, key, buffer, buflen, 0);
+#else
+ errno = ENOSYS;
+ return -1;
+#endif
+}
+
+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 + 1);
+ retcode = keyctl_read(key, loc_buf, retcode + 1);
+ /*
+ * We don't have key operations locks between syscalls.
+ * For example, the key could have been removed or expired.
+ */
+ if (retcode >= 0) {
+ loc_buf[retcode] = '\0';
+ *buffer = loc_buf;
+ } else {
+ g_free(loc_buf);
+ }
+ return retcode;
+}
+
static void
qcrypto_secret_load_data(QCryptoSecret *secret,
uint8_t **output,
@@ -41,10 +77,28 @@ qcrypto_secret_load_data(QCryptoSecret *secret,
*output = NULL;
*outputlen = 0;
- if (secret->file) {
+ if (secret->syskey) {
+ uint8_t *buffer = NULL;
+ long retcode;
+ if (secret->data || secret->file) {
+ error_setg(errp,
+ "'syskey', 'file' and 'data' are mutually exclusive");
+ return;
+ }
+ retcode = keyctl_read_alloc(secret->syskey, &buffer);
+ if (retcode < 0) {
+ error_setg_errno(errp, errno,
+ "Unable to read serial key %08x",
+ secret->syskey);
+ return;
+ } else {
+ *outputlen = retcode;
+ *output = buffer;
+ }
+ } else if (secret->file) {
if (secret->data) {
error_setg(errp,
- "'file' and 'data' are mutually exclusive");
+ "'syskey', 'file' and 'data' are mutually exclusive");
return;
}
if (!g_file_get_contents(secret->file, &data, &length, &gerr)) {
@@ -60,7 +114,8 @@ qcrypto_secret_load_data(QCryptoSecret *secret,
*outputlen = strlen(secret->data);
*output = (uint8_t *)g_strdup(secret->data);
} else {
- error_setg(errp, "Either 'file' or 'data' must be provided");
+ error_setg(errp,
+ "Either 'syskey' or 'file' or 'data' must be provided");
}
}
@@ -298,6 +353,29 @@ qcrypto_secret_prop_get_file(Object *obj,
}
+static void
+qcrypto_secret_prop_set_syskey(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ QCryptoSecret *secret = QCRYPTO_SECRET(obj);
+ int32_t value;
+ visit_type_int32(v, name, &value, errp);
+ secret->syskey = value;
+}
+
+
+static void
+qcrypto_secret_prop_get_syskey(Object *obj, Visitor *v,
+ const char *name, void *opaque,
+ Error **errp)
+{
+ QCryptoSecret *secret = QCRYPTO_SECRET(obj);
+ int32_t value = secret->syskey;
+ visit_type_int32(v, name, &value, errp);
+}
+
+
static void
qcrypto_secret_prop_set_iv(Object *obj,
const char *value,
@@ -384,6 +462,10 @@ qcrypto_secret_class_init(ObjectClass *oc, void *data)
qcrypto_secret_prop_get_file,
qcrypto_secret_prop_set_file,
NULL);
+ object_class_property_add(oc, "syskey", "key_serial_t",
+ qcrypto_secret_prop_get_syskey,
+ qcrypto_secret_prop_set_syskey,
+ NULL, NULL, NULL);
object_class_property_add_str(oc, "keyid",
qcrypto_secret_prop_get_keyid,
qcrypto_secret_prop_set_keyid,
diff --git a/include/crypto/secret.h b/include/crypto/secret.h
index 5e07e29bae..9d350e35ed 100644
--- a/include/crypto/secret.h
+++ b/include/crypto/secret.h
@@ -31,6 +31,8 @@
typedef struct QCryptoSecret QCryptoSecret;
typedef struct QCryptoSecretClass QCryptoSecretClass;
+typedef int32_t key_serial_t;
+
/**
* QCryptoSecret:
*
@@ -125,6 +127,7 @@ struct QCryptoSecret {
QCryptoSecretFormat format;
char *data;
char *file;
+ key_serial_t syskey;
char *keyid;
char *iv;
};
--
2.17.1
Patchew URL: https://patchew.org/QEMU/20200328114014.6362-1-alex-krasikov@yandex-team.ru/
Hi,
This series failed the docker-mingw@fedora build test. Please find the testing commands and
their output below. If you have Docker installed, you can probably reproduce it
locally.
=== TEST SCRIPT BEGIN ===
#! /bin/bash
export ARCH=x86_64
make docker-image-fedora V=1 NETWORK=1
time make docker-test-mingw@fedora J=14 NETWORK=1
=== TEST SCRIPT END ===
CC chardev/char-ringbuf.o
CC chardev/char-serial.o
CC chardev/char-socket.o
/tmp/qemu-test/src/crypto/secret.c:22:10: fatal error: asm/unistd.h: No such file or directory
#include <asm/unistd.h>
^~~~~~~~~~~~~~
compilation terminated.
make: *** [/tmp/qemu-test/src/rules.mak:69: crypto/secret.o] Error 1
make: *** Waiting for unfinished jobs....
Traceback (most recent call last):
File "./tests/docker/docker.py", line 664, in <module>
---
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['sudo', '-n', 'docker', 'run', '--label', 'com.qemu.instance.uuid=4961116ada114c5d93e518eb1e9d8685', '-u', '1003', '--security-opt', 'seccomp=unconfined', '--rm', '-e', 'TARGET_LIST=', '-e', 'EXTRA_CONFIGURE_OPTS=', '-e', 'V=', '-e', 'J=14', '-e', 'DEBUG=', '-e', 'SHOW_ENV=', '-e', 'CCACHE_DIR=/var/tmp/ccache', '-v', '/home/patchew2/.cache/qemu-docker-ccache:/var/tmp/ccache:z', '-v', '/var/tmp/patchew-tester-tmp-rgq6jw7h/src/docker-src.2020-03-28-11.34.05.19902:/var/tmp/qemu:z,ro', 'qemu:fedora', '/var/tmp/qemu/run', 'test-mingw']' returned non-zero exit status 2.
filter=--filter=label=com.qemu.instance.uuid=4961116ada114c5d93e518eb1e9d8685
make[1]: *** [docker-run] Error 1
make[1]: Leaving directory `/var/tmp/patchew-tester-tmp-rgq6jw7h/src'
make: *** [docker-run-test-mingw@fedora] Error 2
real 1m49.176s
user 0m7.677s
The full log is available at
http://patchew.org/logs/20200328114014.6362-1-alex-krasikov@yandex-team.ru/testing.docker-mingw@fedora/?type=message.
---
Email generated automatically by Patchew [https://patchew.org/].
Please send your feedback to patchew-devel@redhat.com
On Sat, Mar 28, 2020 at 02:40:14PM +0300, Alexey Krasikov wrote:
> 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.
This looks like a generally useful concept to me, however, I think
it highlights a mistake in the original secrets design. We should
have had TYPE_QCRYPTO_SECRET be an abstract interface, and then
had subclasses TYPE_QCRYPTO_SECRET_FILE, TYPE_QCRYPTO_SECRET_INLINE
Then we could add TYPE_QCRYPTO_SECRET_LINUX.
We can still mostly fix that mistake now though.
We can introduce a TYPE_QCRYPTO_SECRET_INTERFACE which defines
the generic interface. This interface just needs to define one
API entry point
"char *get_data(QCryptoSecretInterface *secret)"
The current TYPE_QCRYPTO_SECRET can be the current impl of that
interface that returns the rawdata field.
Then we can add the new TYPE_QCRYPTO_SECRET_LINUX for the keyring
implementation that does the Linux specific magic. This will let
us easily compile out the Linux impl on platforms where it is not
available too.
>
> Signed-off-by: Alexey Krasikov <alex-krasikov@yandex-team.ru>
> ---
> crypto/secret.c | 88 +++++++++++++++++++++++++++++++++++++++--
> include/crypto/secret.h | 3 ++
> 2 files changed, 88 insertions(+), 3 deletions(-)
>
> diff --git a/crypto/secret.c b/crypto/secret.c
> index 1cf0ad0ce8..2e8be6241c 100644
> --- a/crypto/secret.c
> +++ b/crypto/secret.c
> @@ -19,6 +19,8 @@
> */
>
> #include "qemu/osdep.h"
> +#include <asm/unistd.h>
> +#include <linux/keyctl.h>
> #include "crypto/secret.h"
> #include "crypto/cipher.h"
> #include "qapi/error.h"
> @@ -28,6 +30,40 @@
> #include "trace.h"
>
>
> +static inline
> +long keyctl_read(key_serial_t key, uint8_t *buffer, size_t buflen)
> +{
> +#ifdef __NR_keyctl
> + return syscall(__NR_keyctl, KEYCTL_READ, key, buffer, buflen, 0);
> +#else
> + errno = ENOSYS;
> + return -1;
> +#endif
> +}
> +
> +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 + 1);
> + retcode = keyctl_read(key, loc_buf, retcode + 1);
> + /*
> + * We don't have key operations locks between syscalls.
> + * For example, the key could have been removed or expired.
> + */
> + if (retcode >= 0) {
> + loc_buf[retcode] = '\0';
> + *buffer = loc_buf;
> + } else {
> + g_free(loc_buf);
> + }
> + return retcode;
> +}
> +
> static void
> qcrypto_secret_load_data(QCryptoSecret *secret,
> uint8_t **output,
> @@ -41,10 +77,28 @@ qcrypto_secret_load_data(QCryptoSecret *secret,
> *output = NULL;
> *outputlen = 0;
>
> - if (secret->file) {
> + if (secret->syskey) {
> + uint8_t *buffer = NULL;
> + long retcode;
> + if (secret->data || secret->file) {
> + error_setg(errp,
> + "'syskey', 'file' and 'data' are mutually exclusive");
> + return;
> + }
> + retcode = keyctl_read_alloc(secret->syskey, &buffer);
> + if (retcode < 0) {
> + error_setg_errno(errp, errno,
> + "Unable to read serial key %08x",
> + secret->syskey);
> + return;
> + } else {
> + *outputlen = retcode;
> + *output = buffer;
> + }
> + } else if (secret->file) {
> if (secret->data) {
> error_setg(errp,
> - "'file' and 'data' are mutually exclusive");
> + "'syskey', 'file' and 'data' are mutually exclusive");
> return;
> }
> if (!g_file_get_contents(secret->file, &data, &length, &gerr)) {
> @@ -60,7 +114,8 @@ qcrypto_secret_load_data(QCryptoSecret *secret,
> *outputlen = strlen(secret->data);
> *output = (uint8_t *)g_strdup(secret->data);
> } else {
> - error_setg(errp, "Either 'file' or 'data' must be provided");
> + error_setg(errp,
> + "Either 'syskey' or 'file' or 'data' must be provided");
> }
> }
>
> @@ -298,6 +353,29 @@ qcrypto_secret_prop_get_file(Object *obj,
> }
>
>
> +static void
> +qcrypto_secret_prop_set_syskey(Object *obj, Visitor *v,
> + const char *name, void *opaque,
> + Error **errp)
> +{
> + QCryptoSecret *secret = QCRYPTO_SECRET(obj);
> + int32_t value;
> + visit_type_int32(v, name, &value, errp);
> + secret->syskey = value;
> +}
> +
> +
> +static void
> +qcrypto_secret_prop_get_syskey(Object *obj, Visitor *v,
> + const char *name, void *opaque,
> + Error **errp)
> +{
> + QCryptoSecret *secret = QCRYPTO_SECRET(obj);
> + int32_t value = secret->syskey;
> + visit_type_int32(v, name, &value, errp);
> +}
> +
> +
> static void
> qcrypto_secret_prop_set_iv(Object *obj,
> const char *value,
> @@ -384,6 +462,10 @@ qcrypto_secret_class_init(ObjectClass *oc, void *data)
> qcrypto_secret_prop_get_file,
> qcrypto_secret_prop_set_file,
> NULL);
> + object_class_property_add(oc, "syskey", "key_serial_t",
> + qcrypto_secret_prop_get_syskey,
> + qcrypto_secret_prop_set_syskey,
> + NULL, NULL, NULL);
> object_class_property_add_str(oc, "keyid",
> qcrypto_secret_prop_get_keyid,
> qcrypto_secret_prop_set_keyid,
> diff --git a/include/crypto/secret.h b/include/crypto/secret.h
> index 5e07e29bae..9d350e35ed 100644
> --- a/include/crypto/secret.h
> +++ b/include/crypto/secret.h
> @@ -31,6 +31,8 @@
> typedef struct QCryptoSecret QCryptoSecret;
> typedef struct QCryptoSecretClass QCryptoSecretClass;
>
> +typedef int32_t key_serial_t;
> +
> /**
> * QCryptoSecret:
> *
> @@ -125,6 +127,7 @@ struct QCryptoSecret {
> QCryptoSecretFormat format;
> char *data;
> char *file;
> + key_serial_t syskey;
> char *keyid;
> char *iv;
> };
> --
> 2.17.1
>
Regards,
Daniel
--
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