[libvirt] [PATCH v2 6/7] storage: Support "chap" authentication for iscsi pool

John Ferlan jferlan at redhat.com
Tue Jul 9 19:10:50 UTC 2013


From: Osier Yang <jyang at redhat.com>

Although the XML for "chap" authentication with plain "password"
was introduced long ago, the function was never implemented.
This patch completes it by performing the authentication during
findPoolSources() processing of pools with an authType of
VIR_STORAGE_POOL_AUTH_CHAP specified.

There are two types of CHAP configurations supported for iSCSI
authentication:

  * Initiator Authentication
      Forward, one-way; The initiator is authenticated by the target.

  * Target Authentication
      Reverse, Bi-directional, mutual, two-way; The target is authenticated
      by the initiator; This method also requires Initiator Authentication

This only supports the "Initiator Authentication". (I don't have any
enterprise iSCSI env for testing, only have a iSCSI target setup with
tgtd, which doesn't support "Target Authentication").

"Discovery authentication" is not supported by tgt yet too. So this only
setup the session authentication by executing 3 iscsiadm commands, E.g:

% iscsiadm -m node --target "iqn.2013-05.test:iscsi.foo" --name \
  "node.session.auth.authmethod" -v "CHAP" --op update

% iscsiadm -m node --target "iqn.2013-05.test:iscsi.foo" --name \
  "node.session.auth.username" -v "Jim" --op update

% iscsiadm -m node --target "iqn.2013-05.test:iscsi.foo" --name \
  "node.session.auth.password" -v "Jimsecret" --op update

Update storage_backend_rbd.c to use the internal API to get the secret
value instead and error out if the secret value is not found. Without the
flag VIR_SECRET_GET_VALUE_INTERNAL_CALL, there is no way to get the value
of private secret.

Update the formatstorage.html to describe the usage of the secret element
to mention that the secret type "iscsi" and "ceph" can be used
to storage pool too.

Update the formatsecret.html to include a reference to the storage pool
---
 docs/formatsecret.html.in           |  10 ++--
 docs/formatstorage.html.in          |  31 +++++++++-
 src/storage/storage_backend_iscsi.c | 113 +++++++++++++++++++++++++++++++++++-
 src/storage/storage_backend_rbd.c   |  13 ++++-
 4 files changed, 159 insertions(+), 8 deletions(-)

diff --git a/docs/formatsecret.html.in b/docs/formatsecret.html.in
index 50c9533..3e306b5 100644
--- a/docs/formatsecret.html.in
+++ b/docs/formatsecret.html.in
@@ -64,8 +64,9 @@
       a single <code>name</code> element that specifies a usage name
       for the secret.  The Ceph secret can then be used by UUID or by
       this usage name via the <code><auth></code> element of
-      a <a href="formatdomain.html#elementsDisks">disk
-      device</a>. <span class="since">Since 0.9.7</span>.
+      a <a href="formatdomain.html#elementsDisks">disk device</a> or
+      a <a href="formatstorage.html">storage pool (rbd)</a>.
+      <span class="since">Since 0.9.7</span>.
     </p>
 
     <h3>Usage type "iscsi"</h3>
@@ -76,8 +77,9 @@
       a single <code>target</code> element that specifies a usage name
       for the secret.  The iSCSI secret can then be used by UUID or by
       this usage name via the <code><auth></code> element of
-      a <a href="formatdomain.html#elementsDisks">disk
-      device</a>. <span class="since">Since 1.0.4</span>.
+      a <a href="formatdomain.html#elementsDisks">disk device</a> or
+      a <a href="formatstorage.html">storage pool (iscsi)</a>.
+      <span class="since">Since 1.0.4</span>.
     </p>
 
     <h2><a name="example">Example</a></h2>
diff --git a/docs/formatstorage.html.in b/docs/formatstorage.html.in
index d702eb1..cf028dd 100644
--- a/docs/formatstorage.html.in
+++ b/docs/formatstorage.html.in
@@ -72,6 +72,9 @@
         <source>
           <host name="iscsi.example.com"/>
           <device path="demo-target"/>
+          <auth type='chap' username='myname'>
+            <secret type='iscsi' usage='mycluster_myname'/>
+          </auth>
           <vendor name="Acme"/>
           <product name="model"/>
         </source>
@@ -80,7 +83,6 @@
     <pre>
         ...
         <source>
-        <source>
           <adapter type='fc_host' parent='scsi_host5' wwnn='20000000c9831b4b' wwpn='10000000c9831b4b'/>
         </source>
         ...</pre>
@@ -123,6 +125,33 @@
         which is the hostname or IP address of the server. May optionally
         contain a <code>port</code> attribute for the protocol specific
         port number. <span class="since">Since 0.4.1</span></dd>
+      <dt><code>auth</code></dt>
+      <dd>If present, the <code>auth</code> element provides the
+        authentication credentials needed to access the source by the
+        setting of the <code>type</code> attribute. The <code>type</code>
+        must be either "chap" or "ceph". For a "chap" <code>type</code>
+        attribute, mandatory attributes <code>login</code> or
+        <code>username</code> and either a <code>passwd</code> or a
+        <code>secret</code> sub-element are used to provide the
+        authentication identification. <span class="since">Since 1.1.1,</span>
+        when writing out the XML, libvirt will utilize the
+        <code>username</code> instead of <code>login</code>.
+        For a "ceph" <code>type</code> attribute a mandatory attribute
+        <code>username</code>, which identifies the username to use during
+        authentication as well as a sub-element <code>secret</code> with
+        a mandatory attribute <code>type</code>, to tie back to a
+        <a href="formatsecret.html">libvirt secret object</a> that
+        holds the actual password or other credentials. The domain XML
+        intentionally does not expose the password, only the reference
+        to the object that does manage the password. The secret element
+        <code>type</code> must be either "ceph" or "iscsi". Use "ceph" for
+        Ceph RBD (rados block device) network sources and use "iscsi" for CHAP
+        (Challenge-Handshake Authentication Protocol) iSCSI targets.
+        The <code>secret</code> element requires either a <code>uuid</code>
+        attribute with the UUID of the secret object or a <code>usage</code>
+        attribute matching the key that was specified in the
+        secret object.  <span class="since">Since 0.9.7</span>
+      </dd>
       <dt><code>name</code></dt>
       <dd>Provides the source for pools backed by storage from a
         named element (e.g., a logical volume group name).
diff --git a/src/storage/storage_backend_iscsi.c b/src/storage/storage_backend_iscsi.c
index 0a4cd22..673ca16 100644
--- a/src/storage/storage_backend_iscsi.c
+++ b/src/storage/storage_backend_iscsi.c
@@ -32,6 +32,8 @@
 #include <unistd.h>
 #include <sys/stat.h>
 
+#include "datatypes.h"
+#include "driver.h"
 #include "virerror.h"
 #include "storage_backend_scsi.h"
 #include "storage_backend_iscsi.h"
@@ -39,6 +41,7 @@
 #include "virlog.h"
 #include "virfile.h"
 #include "vircommand.h"
+#include "virobject.h"
 #include "virrandom.h"
 #include "virstring.h"
 
@@ -545,9 +548,112 @@ cleanup:
     return ret;
 }
 
+static int
+virStorageBackendISCSINodeUpdate(const char *portal,
+                                 const char *target,
+                                 const char *name,
+                                 const char *value)
+{
+     virCommandPtr cmd = NULL;
+     int status;
+     int ret = -1;
+
+     cmd = virCommandNewArgList(ISCSIADM,
+                                "--mode", "node",
+                                "--portal", portal,
+                                "--target", target,
+                                "--op", "update",
+                                "--name", name,
+                                "--value", value,
+                                NULL);
+
+    if (virCommandRun(cmd, &status) < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("Failed to update '%s' of node mode for target '%s'"),
+                       name, target);
+        goto cleanup;
+    }
+
+    ret = 0;
+cleanup:
+    virCommandFree(cmd);
+    return ret;
+}
+
+static int
+virStorageBackendISCSISetAuth(const char *portal,
+                              virConnectPtr conn,
+                              virStoragePoolSourcePtr source)
+{
+    virSecretPtr secret = NULL;
+    unsigned char *secret_value = NULL;
+    const char *passwd = NULL;
+    virStoragePoolAuthChap chap;
+    int ret = -1;
+
+    if (source->authType == VIR_STORAGE_POOL_AUTH_NONE)
+        return 0;
+
+    if (source->authType != VIR_STORAGE_POOL_AUTH_CHAP) {
+        virReportError(VIR_ERR_XML_ERROR, "%s",
+                       _("iscsi pool only supports 'chap' auth type"));
+        return -1;
+    }
+
+    chap = source->auth.chap;
+    if (chap.type == VIR_STORAGE_POOL_AUTH_CHAP_SECRET) {
+        if (chap.u.secret.uuidUsable)
+            secret = virSecretLookupByUUID(conn, chap.u.secret.uuid);
+        else
+            secret = virSecretLookupByUsage(conn, VIR_SECRET_USAGE_TYPE_ISCSI,
+                                            chap.u.secret.usage);
+
+        if (secret) {
+            size_t secret_size;
+            secret_value =
+                conn->secretDriver->secretGetValue(secret, &secret_size, 0,
+                                                   VIR_SECRET_GET_VALUE_INTERNAL_CALL);
+            if (!secret_value) {
+                virReportError(VIR_ERR_INTERNAL_ERROR,
+                               _("could not get the value of the secret "
+                                 "for username %s"), chap.login);
+                goto cleanup;
+            }
+        } else {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("username '%s' specified but secret not found"),
+                           chap.login);
+            goto cleanup;
+        }
+        passwd = (const char *)secret_value;
+    } else if (chap.type == VIR_STORAGE_POOL_AUTH_CHAP_PLAIN_PASSWORD) {
+        passwd = chap.u.passwd;
+    }
+
+    if (virStorageBackendISCSINodeUpdate(portal,
+                                         source->devices[0].path,
+                                         "node.session.auth.authmethod",
+                                         "CHAP") < 0 ||
+        virStorageBackendISCSINodeUpdate(portal,
+                                         source->devices[0].path,
+                                         "node.session.auth.username",
+                                         source->auth.chap.login) < 0 ||
+        virStorageBackendISCSINodeUpdate(portal,
+                                         source->devices[0].path,
+                                         "node.session.auth.password",
+                                         passwd) < 0)
+        goto cleanup;
+
+    ret = 0;
+
+cleanup:
+    virObjectUnref(secret);
+    VIR_FREE(secret_value);
+    return ret;
+}
 
 static char *
-virStorageBackendISCSIFindPoolSources(virConnectPtr conn ATTRIBUTE_UNUSED,
+virStorageBackendISCSIFindPoolSources(virConnectPtr conn,
                                       const char *srcSpec,
                                       unsigned int flags)
 {
@@ -590,6 +696,9 @@ virStorageBackendISCSIFindPoolSources(virConnectPtr conn ATTRIBUTE_UNUSED,
                                           &ntargets, &targets) < 0)
         goto cleanup;
 
+    if (virStorageBackendISCSISetAuth(portal, conn, source) < 0)
+        goto cleanup;
+
     if (VIR_ALLOC_N(list.sources, ntargets) < 0) {
         virReportOOMError();
         goto cleanup;
@@ -668,7 +777,6 @@ virStorageBackendISCSICheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
     return ret;
 }
 
-
 static int
 virStorageBackendISCSIStartPool(virConnectPtr conn ATTRIBUTE_UNUSED,
                                 virStoragePoolObjPtr pool)
@@ -700,6 +808,7 @@ virStorageBackendISCSIStartPool(virConnectPtr conn ATTRIBUTE_UNUSED,
     if ((session = virStorageBackendISCSISession(pool, 1)) == NULL) {
         if ((portal = virStorageBackendISCSIPortal(&pool->def->source)) == NULL)
             goto cleanup;
+
         /*
          * iscsiadm doesn't let you login to a target, unless you've
          * first issued a 'sendtargets' command to the portal :-(
diff --git a/src/storage/storage_backend_rbd.c b/src/storage/storage_backend_rbd.c
index 953a8ee..d66d3f9 100644
--- a/src/storage/storage_backend_rbd.c
+++ b/src/storage/storage_backend_rbd.c
@@ -23,6 +23,7 @@
 
 #include <config.h>
 
+#include "datatypes.h"
 #include "virerror.h"
 #include "storage_backend_rbd.h"
 #include "storage_conf.h"
@@ -88,7 +89,17 @@ static int virStorageBackendRBDOpenRADOSConn(virStorageBackendRBDStatePtr *ptr,
             goto cleanup;
         }
 
-        secret_value = virSecretGetValue(secret, &secret_value_size, 0);
+        secret_value = conn->secretDriver->secretGetValue(secret, &secret_value_size, 0,
+                                                          VIR_SECRET_GET_VALUE_INTERNAL_CALL);
+
+        if (!secret_value) {
+            virReportError(VIR_ERR_INTERNAL_ERROR,
+                           _("could not get the value of the secret "
+                             "for username %s"),
+                           pool->def->source.auth.cephx.username);
+            goto cleanup;
+        }
+
         base64_encode_alloc((char *)secret_value,
                             secret_value_size, &rados_key);
         memset(secret_value, 0, secret_value_size);
-- 
1.8.1.4




More information about the libvir-list mailing list