1:18 p.m.
If the <encryption format='qcow'> element does not specify a secret
during volume creation, generate a suitable secret and add it to the
<encryption> tag. The caller can view the updated <encryption> tag
using virStorageVolGetXMLDesc().
Similarly, when <encryption format='default'/> is specified while
creating a qcow or qcow2-formatted volume, change the format to "qcow"
and generate a secret as described above.
Changes since the third submission:
- Add "flags" parameter to virSecretDefineXML(), virSecretGetXMLDesc(),
virSecretGetValue(), virSecretSetValue(), and all derived interfaces.
---
src/storage_backend.c | 127 +++++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 124 insertions(+), 3 deletions(-)
diff --git a/src/storage_backend.c b/src/storage_backend.c
index c818142..5fa0035 100644
--- a/src/storage_backend.c
+++ b/src/storage_backend.c
@@ -43,6 +43,7 @@
#include <selinux/selinux.h>
#endif
+#include "datatypes.h"
#include "virterror_internal.h"
#include "util.h"
#include "memory.h"
@@ -331,6 +332,118 @@ cleanup:
}
static int
+virStorageGenerateQcowEncryption(virConnectPtr conn,
+ virStorageVolDefPtr vol)
+{
+ virBuffer buf = VIR_BUFFER_INITIALIZER;
+ virStorageEncryptionPtr enc;
+ virStorageEncryptionSecretPtr enc_secret = NULL;
+ virSecretPtr secret = NULL;
+ char *uuid = NULL, *xml;
+ unsigned char value[16];
+ int ret = -1, fd = -1;
+ size_t i;
+
+ if (conn->secretDriver == NULL || conn->secretDriver->defineXML == NULL ||
+ conn->secretDriver->setValue == NULL) {
+ virStorageReportError(conn, VIR_ERR_NO_SUPPORT, "%s",
+ _("secret storage not supported"));
+ goto cleanup;
+ }
+
+ enc = vol->target.encryption;
+ if (enc->nsecrets != 0) {
+ virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR, "%s",
+ _("secrets already defined"));
+ goto cleanup;
+ }
+
+ if (VIR_ALLOC(enc_secret) < 0 || VIR_REALLOC_N(enc->secrets, 1) < 0) {
+ virReportOOMError(conn);
+ goto cleanup;
+ }
+
+ virBufferAddLit(&buf, "<secret ephemeral='no'
private='no'>");
+ /* <uuid/> is chosen by the secret driver */
+ virBufferEscapeString(&buf,
+ "<description>qcow passphrase for
%s</description>",
+ vol->target.path);
+ virBufferEscapeString(&buf, "<volume>%s</volume>",
vol->target.path);
+ virBufferAddLit(&buf, "</secret>");
+ if (virBufferError(&buf)) {
+ virReportOOMError(conn);
+ goto cleanup;
+ }
+ xml = virBufferContentAndReset(&buf);
+ secret = conn->secretDriver->defineXML(conn, xml, 0);
+ if (secret == NULL) {
+ VIR_FREE(xml);
+ goto cleanup;
+ }
+ VIR_FREE(xml);
+
+ uuid = strdup(secret->uuid);
+ if (uuid == NULL) {
+ virReportOOMError(conn);
+ goto cleanup;
+ }
+
+ /* A qcow passphrase is up to 16 bytes, with any data following a NUL
+ ignored. Prohibit control and non-ASCII characters to avoid possible
+ unpleasant surprises with the qemu monitor input mechanism. */
+ fd = open("/dev/urandom", O_RDONLY);
+ if (fd < 0) {
+ virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Cannot open /dev/urandom"));
+ goto cleanup;
+ }
+ i = 0;
+ while (i < sizeof (value)) {
+ ssize_t r;
+
+ while ((r = read(fd, value + i, 1)) == -1 && errno == EINTR)
+ ;
+ if (r <= 0) {
+ virStorageReportError(conn, VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Cannot read from /dev/urandom"));
+ goto cleanup;
+ }
+ if (value[i] >= 0x20 && value[i] <= 0x7E)
+ i++; /* Got an acceptable character */
+ }
+ close(fd);
+ fd = -1;
+
+ if (conn->secretDriver->setValue(secret, value, sizeof(value), 0) < 0)
+ goto cleanup;
+ secret = NULL;
+
+ enc_secret->type = VIR_STORAGE_ENCRYPTION_SECRET_TYPE_PASSPHRASE;
+ enc_secret->uuid = uuid;
+ uuid = NULL;
+ enc->format = VIR_STORAGE_ENCRYPTION_FORMAT_QCOW;
+ enc->secrets[0] = enc_secret; /* Space for secrets[0] allocated above */
+ enc_secret = NULL;
+ enc->nsecrets = 1;
+
+ ret = 0;
+
+cleanup:
+ if (fd != -1)
+ close(fd);
+ VIR_FREE(uuid);
+ if (secret != NULL) {
+ if (conn->secretDriver->undefine != NULL)
+ conn->secretDriver->undefine(secret);
+ virSecretFree(secret);
+ }
+ xml = virBufferContentAndReset(&buf);
+ VIR_FREE(xml);
+ VIR_FREE(enc_secret);
+ return ret;
+}
+
+static int
virStorageBackendCreateQemuImg(virConnectPtr conn,
virStorageVolDefPtr vol,
virStorageVolDefPtr inputvol,
@@ -428,6 +541,8 @@ virStorageBackendCreateQemuImg(virConnectPtr conn,
}
if (vol->target.encryption != NULL) {
+ virStorageEncryptionPtr enc;
+
if (vol->target.format != VIR_STORAGE_VOL_FILE_QCOW &&
vol->target.format != VIR_STORAGE_VOL_FILE_QCOW2) {
virStorageReportError(conn, VIR_ERR_NO_SUPPORT,
@@ -435,18 +550,24 @@ virStorageBackendCreateQemuImg(virConnectPtr conn,
"volume format %s"), type);
return -1;
}
- if (vol->target.encryption->format !=
- VIR_STORAGE_ENCRYPTION_FORMAT_QCOW) {
+ enc = vol->target.encryption;
+ if (enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_QCOW &&
+ enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT) {
virStorageReportError(conn, VIR_ERR_NO_SUPPORT,
_("unsupported volume encryption format
%d"),
vol->target.encryption->format);
return -1;
}
- if (vol->target.encryption->nsecrets > 1) {
+ if (enc->nsecrets > 1) {
virStorageReportError(conn, VIR_ERR_INVALID_STORAGE_VOL,
_("too many secrets for qcow encryption"));
return -1;
}
+ if (enc->format == VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT ||
+ enc->nsecrets == 0) {
+ if (virStorageGenerateQcowEncryption(conn, vol) < 0)
+ return -1;
+ }
}
if ((create_tool = virFindFileInPath("kvm-img")) != NULL)
--
1.6.2.5