[libvirt] [PATCH v3 05/10] encryption: Add <cipher> and <ivgen> to encryption

For a luks device, allow the configuration of a specific cipher to be used for encrypting the volume. Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- docs/formatstorageencryption.html.in | 83 ++++++++++++- docs/schemas/storagecommon.rng | 44 ++++++- src/conf/domain_conf.c | 11 ++ src/util/virstorageencryption.c | 138 +++++++++++++++++++++ src/util/virstorageencryption.h | 14 +++ .../qemuxml2argv-luks-disk-cipher.xml | 45 +++++++ .../qemuxml2xmlout-luks-disk-cipher.xml | 1 + tests/qemuxml2xmltest.c | 1 + tests/storagevolxml2xmlin/vol-luks-cipher.xml | 23 ++++ tests/storagevolxml2xmlout/vol-luks-cipher.xml | 23 ++++ tests/storagevolxml2xmltest.c | 1 + 11 files changed, 378 insertions(+), 6 deletions(-) create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-luks-disk-cipher.xml create mode 120000 tests/qemuxml2xmloutdata/qemuxml2xmlout-luks-disk-cipher.xml create mode 100644 tests/storagevolxml2xmlin/vol-luks-cipher.xml create mode 100644 tests/storagevolxml2xmlout/vol-luks-cipher.xml diff --git a/docs/formatstorageencryption.html.in b/docs/formatstorageencryption.html.in index be73054..0f8401e 100644 --- a/docs/formatstorageencryption.html.in +++ b/docs/formatstorageencryption.html.in @@ -68,6 +68,60 @@ be used as the passphrase to decrypt the volume. <span class="since">Since 2.0.0</span>. </p> + <p> + For volume creation, it is possible to specify the encryption + algorithm used to encrypt the luks volume. The following two + optional elements may be provided for that purpose. It is hypervisor + dependent as to which algorithms are supported. The default algorithm + used by the storage driver backend when using qemu-img to create + the volume is 'aes-256-cbc' using 'essiv' for initialization vector + generation and 'sha256' hash algorithm for both the cipher and the + initialization vector generation. + </p> + + <dl> + <dt><code>cipher</code></dt> + <dd>This element describes the cipher algorithm to be used to either + encrypt or decrypt the luks volume. This element has the following + attributes: + <dl> + <dt><code>name</code></dt> + <dd>The name of the cipher algorithm used for data encryption, + such as 'aes', 'des', 'cast5', 'serpent', 'twofish', etc. + Support of the specific algorithm is storage driver + implementation dependent.</dd> + <dt><code>size</code></dt> + <dd>The size of the cipher in bits, such as '256', '192', '128', + etc. Support of the specific size for a specific cipher is + hypervisor dependent.</dd> + <dt><code>mode</code></dt> + <dd>An optional cipher algorithm mode such as 'cbc', 'xts', + 'ecb', etc. Support of the specific cipher mode is + hypervisor dependent.</dd> + <dt><code>hash</code></dt> + <dd>An optional master key hash algorithm such as 'md5', 'sha1', + 'sha256', etc. Support of the specific hash algorithm is + hypervisor dependent.</dd> + </dl> + </dd> + <dt><code>ivgen</code></dt> + <dd>This optional element describes the initialization vector + generation algorithm used in conjunction with the + <code>cipher</code>. If the <code>cipher</code> is not provided, + then an error will be generated by the parser. + <dl> + <dt><code>name</code></dt> + <dd>The name of the algorithm, such as 'plain', 'plain64', + 'essiv', etc. Support of the specific algorithm is hypervisor + dependent.</dd> + <dt><code>hash</code></dt> + <dd>An optional hash algorithm such as 'md5', 'sha1', 'sha256', + etc. Support of the specific ivgen hash algorithm is hypervisor + dependent.</dd> + </dl> + </dd> + </dl> + <h2><a name="example">Examples</a></h2> @@ -81,9 +135,12 @@ &lt;/encryption&gt;</pre> <p> - Here is a simple example, specifying use of the <code>luks</code> format - where it's assumed that a <code>secret</code> has been defined using a - <code>usage</code> element with a <code>id</code> of "luks_example": + Assuming a <a href="formatsecret.html#luksUsageType"> + <code>luks secret</code></a> is already defined using a + <code>usage</code> element with an <code>name</code> of "luks_example", + a simple example specifying use of the <code>luks</code> format + for either volume creation without a specific cipher being defined or + as part of a domain volume definition: </p> <pre> &lt;encryption format='luks'&gt; @@ -91,5 +148,25 @@ &lt;/encryption&gt; </pre> + <p> + Here is an example, specifying use of the <code>luks</code> format for + a specific cipher algorihm for volume creation: + </p> + <pre> + &lt;volume&gt; + &lt;name&gt;twofish.luks&lt;/name&gt; + &lt;capacity unit='G'&gt;5&lt;/capacity&gt; + &lt;target&gt; + &lt;path&gt;/var/lib/libvirt/images/demo.luks&lt;/path&gt; + &lt;format type='luks'/&gt; + &lt;encryption format='luks'&gt; + &lt;secret type='passphrase' usage='luks_example'/&gt; + &lt;cipher name='twofish' size='256' mode='cbc' hash='sha256'/&gt; + &lt;ivgen name='plain64' hash='sha256'/&gt; + &lt;/encryption&gt; + &lt;/target&gt; + &lt;/volume&gt; + </pre> + </body> </html> diff --git a/docs/schemas/storagecommon.rng b/docs/schemas/storagecommon.rng index 63b55b4..316fbae 100644 --- a/docs/schemas/storagecommon.rng +++ b/docs/schemas/storagecommon.rng @@ -15,9 +15,19 @@ <value>luks</value> </choice> </attribute> - <zeroOrMore> - <ref name='secret'/> - </zeroOrMore> + <interleave> + <zeroOrMore> + <ref name='secret'/> + </zeroOrMore> + <optional> + <element name='cipher'> + <ref name='keycipher'/> + </element> + <element name='ivgen'> + <ref name='keyivgen'/> + </element> + </optional> + </interleave> </element> </define> @@ -136,4 +146,32 @@ </optional> </define> + <define name='keycipher'> + <attribute name='name'> + <text/> + </attribute> + <attribute name='size'> + <ref name="unsignedInt"/> + </attribute> + <optional> + <attribute name='mode'> + <text/> + </attribute> + <attribute name='hash'> + <text/> + </attribute> + </optional> + </define> + + <define name='keyivgen'> + <attribute name='name'> + <text/> + </attribute> + <optional> + <attribute name='hash'> + <text/> + </attribute> + </optional> + </define> + </grammar> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index 79d15c8..8d3a132 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -7857,6 +7857,17 @@ virDomainDiskDefParseXML(virDomainXMLOptionPtr xmlopt, def->startupPolicy = val; } + if (encryption) { + if (encryption->format == VIR_STORAGE_ENCRYPTION_FORMAT_LUKS && + encryption->encinfo.cipher_name) { + + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("supplying the <cipher> for a domain is " + "unnecessary")); + goto error; + } + } + def->dst = target; target = NULL; def->src->auth = authdef; diff --git a/src/util/virstorageencryption.c b/src/util/virstorageencryption.c index 8575416..754444d 100644 --- a/src/util/virstorageencryption.c +++ b/src/util/virstorageencryption.c @@ -35,6 +35,7 @@ #include "viruuid.h" #include "virfile.h" #include "virsecret.h" +#include "virstring.h" #define VIR_FROM_THIS VIR_FROM_STORAGE @@ -46,6 +47,17 @@ VIR_ENUM_IMPL(virStorageEncryptionFormat, "default", "qcow", "luks") static void +virStorageEncryptionInfoDefFree(virStorageEncryptionInfoDefPtr def) +{ + VIR_FREE(def->cipher_name); + VIR_FREE(def->cipher_mode); + VIR_FREE(def->cipher_hash); + VIR_FREE(def->ivgen_name); + VIR_FREE(def->ivgen_hash); +} + + +static void virStorageEncryptionSecretFree(virStorageEncryptionSecretPtr secret) { if (!secret) @@ -63,6 +75,7 @@ virStorageEncryptionFree(virStorageEncryptionPtr enc) for (i = 0; i < enc->nsecrets; i++) virStorageEncryptionSecretFree(enc->secrets[i]); + virStorageEncryptionInfoDefFree(&enc->encinfo); VIR_FREE(enc->secrets); VIR_FREE(enc); } @@ -80,6 +93,23 @@ virStorageEncryptionSecretCopy(const virStorageEncryptionSecret *src) return ret; } + +static int +virStorageEncryptionInfoDefCopy(const virStorageEncryptionInfoDef *src, + virStorageEncryptionInfoDefPtr dst) +{ + dst->cipher_size = src->cipher_size; + if (VIR_STRDUP(dst->cipher_name, src->cipher_name) < 0 || + VIR_STRDUP(dst->cipher_mode, src->cipher_mode) < 0 || + VIR_STRDUP(dst->cipher_hash, src->cipher_hash) < 0 || + VIR_STRDUP(dst->ivgen_name, src->ivgen_name) < 0 || + VIR_STRDUP(dst->ivgen_hash, src->ivgen_hash) < 0) + return -1; + + return 0; +} + + virStorageEncryptionPtr virStorageEncryptionCopy(const virStorageEncryption *src) { @@ -100,6 +130,9 @@ virStorageEncryptionCopy(const virStorageEncryption *src) goto error; } + if (virStorageEncryptionInfoDefCopy(&src->encinfo, &ret->encinfo) < 0) + goto error; + return ret; error: @@ -153,6 +186,63 @@ virStorageEncryptionSecretParse(xmlXPathContextPtr ctxt, return NULL; } + +static int +virStorageEncryptionInfoParseCipher(xmlNodePtr info_node, + virStorageEncryptionInfoDefPtr info) +{ + int ret = -1; + char *size_str = NULL; + + if (!(info->cipher_name = virXMLPropString(info_node, "name"))) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("missing cipher info name string")); + goto cleanup; + } + + if ((size_str = virXMLPropString(info_node, "size")) && + virStrToLong_uip(size_str, NULL, 10, &info->cipher_size) < 0) { + virReportError(VIR_ERR_XML_ERROR, + _("cannot parse cipher info size string '%s'"), + size_str); + goto cleanup; + } + + if (!size_str) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("cipher info missing 'size' attribute")); + goto cleanup; + } + + /* Optional */ + info->cipher_mode = virXMLPropString(info_node, "mode"); + info->cipher_hash = virXMLPropString(info_node, "hash"); + + ret = 0; + + cleanup: + VIR_FREE(size_str); + return ret; +} + + +static int +virStorageEncryptionInfoParseIvgen(xmlNodePtr info_node, + virStorageEncryptionInfoDefPtr info) +{ + if (!(info->ivgen_name = virXMLPropString(info_node, "name"))) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("missing ivgen info name string")); + return -1; + } + + /* Optional */ + info->ivgen_hash = virXMLPropString(info_node, "hash"); + + return 0; +} + + static virStorageEncryptionPtr virStorageEncryptionParseXML(xmlXPathContextPtr ctxt) { @@ -196,6 +286,28 @@ virStorageEncryptionParseXML(xmlXPathContextPtr ctxt) VIR_FREE(nodes); } + if (ret->format == VIR_STORAGE_ENCRYPTION_FORMAT_LUKS) { + xmlNodePtr tmpnode; + + if ((tmpnode = virXPathNode("./cipher[1]", ctxt))) { + if (virStorageEncryptionInfoParseCipher(tmpnode, &ret->encinfo) < 0) + goto cleanup; + } + + if ((tmpnode = virXPathNode("./ivgen[1]", ctxt))) { + /* If no cipher node, then fail */ + if (!ret->encinfo.cipher_name) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("missing storage encryption cipher")); + goto cleanup; + } + + if (virStorageEncryptionInfoParseIvgen(tmpnode, &ret->encinfo) < 0) + goto cleanup; + } + } + + return ret; cleanup: @@ -250,6 +362,28 @@ virStorageEncryptionSecretFormat(virBufferPtr buf, return 0; } + +static void +virStorageEncryptionInfoDefFormat(virBufferPtr buf, + const virStorageEncryptionInfoDef *enc) +{ + virBufferAsprintf(buf, "<cipher name='%s' size='%u'", + enc->cipher_name, enc->cipher_size); + if (enc->cipher_mode) + virBufferAsprintf(buf, " mode='%s'", enc->cipher_mode); + if (enc->cipher_hash) + virBufferAsprintf(buf, " hash='%s'", enc->cipher_hash); + virBufferAddLit(buf, "/>\n"); + + if (enc->ivgen_name) { + virBufferAsprintf(buf, "<ivgen name='%s'", enc->ivgen_name); + if (enc->ivgen_hash) + virBufferAsprintf(buf, " hash='%s'", enc->ivgen_hash); + virBufferAddLit(buf, "/>\n"); + } +} + + int virStorageEncryptionFormat(virBufferPtr buf, virStorageEncryptionPtr enc) @@ -270,6 +404,10 @@ virStorageEncryptionFormat(virBufferPtr buf, return -1; } + if (enc->format == VIR_STORAGE_ENCRYPTION_FORMAT_LUKS && + enc->encinfo.cipher_name) + virStorageEncryptionInfoDefFormat(buf, &enc->encinfo); + virBufferAdjustIndent(buf, -2); virBufferAddLit(buf, "</encryption>\n"); diff --git a/src/util/virstorageencryption.h b/src/util/virstorageencryption.h index 5e1be3b..fa439fb 100644 --- a/src/util/virstorageencryption.h +++ b/src/util/virstorageencryption.h @@ -44,6 +44,18 @@ struct _virStorageEncryptionSecret { virSecretLookupTypeDef seclookupdef; }; +/* It's possible to dictate the cipher and if necessary iv */ +typedef struct _virStorageEncryptionInfoDef virStorageEncryptionInfoDef; +typedef virStorageEncryptionInfoDef *virStorageEncryptionInfoDefPtr; +struct _virStorageEncryptionInfoDef { + unsigned int cipher_size; + char *cipher_name; + char *cipher_mode; + char *cipher_hash; + char *ivgen_name; + char *ivgen_hash; +}; + typedef enum { /* "default" is only valid for volume creation */ VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT = 0, @@ -61,6 +73,8 @@ struct _virStorageEncryption { size_t nsecrets; virStorageEncryptionSecretPtr *secrets; + + virStorageEncryptionInfoDef encinfo; }; virStorageEncryptionPtr virStorageEncryptionCopy(const virStorageEncryption *src) diff --git a/tests/qemuxml2argvdata/qemuxml2argv-luks-disk-cipher.xml b/tests/qemuxml2argvdata/qemuxml2argv-luks-disk-cipher.xml new file mode 100644 index 0000000..9ce15c0 --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-luks-disk-cipher.xml @@ -0,0 +1,45 @@ +<domain type='qemu'> + <name>encryptdisk</name> + <uuid>496898a6-e6ff-f7c8-5dc2-3cf410945ee9</uuid> + <memory unit='KiB'>1048576</memory> + <currentMemory unit='KiB'>524288</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='x86_64' machine='pc-i440fx-2.1'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu</emulator> + <disk type='file' device='disk'> + <driver name='qemu' type='luks'/> + <source file='/storage/guest_disks/encryptdisk'/> + <target dev='vda' bus='virtio'/> + <encryption format='luks'> + <secret type='passphrase' uuid='0a81f5b2-8403-7b23-c8d6-21ccc2f80d6f'/> + </encryption> + <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> + </disk> + <disk type='file' device='disk'> + <driver name='qemu' type='luks'/> + <source file='/storage/guest_disks/encryptdisk2'/> + <target dev='vdb' bus='virtio'/> + <encryption format='luks'> + <secret type='passphrase' usage='mycluster_myname'/> + </encryption> + <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> + </disk> + <controller type='usb' index='0'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> + </controller> + <controller type='pci' index='0' model='pci-root'/> + <input type='mouse' bus='ps2'/> + <input type='keyboard' bus='ps2'/> + <memballoon model='virtio'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> + </memballoon> + </devices> +</domain> diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-luks-disk-cipher.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-luks-disk-cipher.xml new file mode 120000 index 0000000..fa55233 --- /dev/null +++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-luks-disk-cipher.xml @@ -0,0 +1 @@ +../qemuxml2argvdata/qemuxml2argv-luks-disk-cipher.xml \ No newline at end of file diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c index 6c566b3..2056c03 100644 --- a/tests/qemuxml2xmltest.c +++ b/tests/qemuxml2xmltest.c @@ -503,6 +503,7 @@ mymain(void) DO_TEST("encrypted-disk"); DO_TEST("encrypted-disk-usage"); DO_TEST("luks-disks"); + DO_TEST("luks-disk-cipher"); DO_TEST("memtune"); DO_TEST("memtune-unlimited"); DO_TEST("blkiotune"); diff --git a/tests/storagevolxml2xmlin/vol-luks-cipher.xml b/tests/storagevolxml2xmlin/vol-luks-cipher.xml new file mode 100644 index 0000000..009246f --- /dev/null +++ b/tests/storagevolxml2xmlin/vol-luks-cipher.xml @@ -0,0 +1,23 @@ +<volume> + <name>LuksDemo.img</name> + <key>/var/lib/libvirt/images/LuksDemo.img</key> + <source> + </source> + <capacity unit="G">5</capacity> + <allocation>294912</allocation> + <target> + <path>/var/lib/libvirt/images/LuksDemo.img</path> + <format type='luks'/> + <permissions> + <mode>0644</mode> + <owner>0</owner> + <group>0</group> + <label>unconfined_u:object_r:virt_image_t:s0</label> + </permissions> + <encryption format='luks'> + <secret type='passphrase' usage='mumblyfratz'/> + <cipher name='serpent' size='256' mode='cbc' hash='sha256'/> + <ivgen name='plain64' hash='sha256'/> + </encryption> + </target> +</volume> diff --git a/tests/storagevolxml2xmlout/vol-luks-cipher.xml b/tests/storagevolxml2xmlout/vol-luks-cipher.xml new file mode 100644 index 0000000..9014849 --- /dev/null +++ b/tests/storagevolxml2xmlout/vol-luks-cipher.xml @@ -0,0 +1,23 @@ +<volume type='file'> + <name>LuksDemo.img</name> + <key>/var/lib/libvirt/images/LuksDemo.img</key> + <source> + </source> + <capacity unit='bytes'>5368709120</capacity> + <allocation unit='bytes'>294912</allocation> + <target> + <path>/var/lib/libvirt/images/LuksDemo.img</path> + <format type='luks'/> + <permissions> + <mode>0644</mode> + <owner>0</owner> + <group>0</group> + <label>unconfined_u:object_r:virt_image_t:s0</label> + </permissions> + <encryption format='luks'> + <secret type='passphrase' usage='mumblyfratz'/> + <cipher name='serpent' size='256' mode='cbc' hash='sha256'/> + <ivgen name='plain64' hash='sha256'/> + </encryption> + </target> +</volume> diff --git a/tests/storagevolxml2xmltest.c b/tests/storagevolxml2xmltest.c index a36a706..db82bea 100644 --- a/tests/storagevolxml2xmltest.c +++ b/tests/storagevolxml2xmltest.c @@ -106,6 +106,7 @@ mymain(void) DO_TEST("pool-dir", "vol-qcow2-0.10-lazy"); DO_TEST("pool-dir", "vol-qcow2-nobacking"); DO_TEST("pool-dir", "vol-luks"); + DO_TEST("pool-dir", "vol-luks-cipher"); DO_TEST("pool-disk", "vol-partition"); DO_TEST("pool-logical", "vol-logical"); DO_TEST("pool-logical", "vol-logical-backing"); -- 2.5.5