[libvirt] [PATCH v5 4/5] storage: Support "chap" authentication for iscsi pool

[Paolo Bonzini]

Il 22/07/2013 22:31, John Ferlan ha scritto:
> Although the XML for CHAP authentication with plain "password"
> was introduced long ago, the function was never implemented. This
> patch replaces the login/password mechanism by following the
> 'ceph' (or RBD) model of using a 'username' with a 'secret' which
> has the authentication information.
> 
> This patch performs the authentication during startPool() processing
> of pools with an authType of VIR_STORAGE_POOL_AUTH_CHAP specified
> for iSCSI pools.
> 
> 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
> ---
>  src/storage/storage_backend_iscsi.c | 111 +++++++++++++++++++++++++++++++++++-
>  1 file changed, 110 insertions(+), 1 deletion(-)
> 
> diff --git a/src/storage/storage_backend_iscsi.c b/src/storage/storage_backend_iscsi.c
> index 54bcd14..388d6ed 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"
>  
> @@ -658,9 +661,112 @@ virStorageBackendISCSICheckPool(virConnectPtr conn ATTRIBUTE_UNUSED,
>      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
> -virStorageBackendISCSIStartPool(virConnectPtr conn ATTRIBUTE_UNUSED,
> +virStorageBackendISCSISetAuth(const char *portal,
> +                              virConnectPtr conn,
> +                              virStoragePoolDefPtr def)
> +{
> +    virSecretPtr secret = NULL;
> +    unsigned char *secret_value = NULL;
> +    virStoragePoolAuthChap chap;
> +    int ret = -1;
> +
> +    if (def->source.authType == VIR_STORAGE_POOL_AUTH_NONE)
> +        return 0;
> +
> +    if (def->source.authType != VIR_STORAGE_POOL_AUTH_CHAP) {
> +        virReportError(VIR_ERR_XML_ERROR, "%s",
> +                       _("iscsi pool only supports 'chap' auth type"));
> +        return -1;
> +    }
> +
> +    if (!conn) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                       _("iscsi 'chap' authentication requires connection"));
> +        return -1;
> +    }

Should this be more precisely "not supported for autostarted pools"?

> +
> +    chap = def->source.auth.chap;
> +    if (chap.secret.uuidUsable)
> +        secret = virSecretLookupByUUID(conn, chap.secret.uuid);
> +    else
> +        secret = virSecretLookupByUsage(conn, VIR_SECRET_USAGE_TYPE_ISCSI,
> +                                        chap.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.username);
> +            goto cleanup;
> +        }
> +    } else {
> +        virReportError(VIR_ERR_INTERNAL_ERROR,
> +                       _("username '%s' specified but secret not found"),
> +                       chap.username);
> +        goto cleanup;
> +    }
> +
> +    if (virStorageBackendISCSINodeUpdate(portal,
> +                                         def->source.devices[0].path,
> +                                         "node.session.auth.authmethod",
> +                                         "CHAP") < 0 ||
> +        virStorageBackendISCSINodeUpdate(portal,
> +                                         def->source.devices[0].path,
> +                                         "node.session.auth.username",
> +                                         chap.username) < 0 ||
> +        virStorageBackendISCSINodeUpdate(portal,
> +                                         def->source.devices[0].path,
> +                                         "node.session.auth.password",
> +                                         (const char *)secret_value) < 0)
> +        goto cleanup;
> +
> +    ret = 0;
> +
> +cleanup:
> +    virObjectUnref(secret);
> +    VIR_FREE(secret_value);
> +    return ret;
> +}
> +
> +static int
> +virStorageBackendISCSIStartPool(virConnectPtr conn,
>                                  virStoragePoolObjPtr pool)
>  {
>      char *portal = NULL;
> @@ -699,6 +805,9 @@ virStorageBackendISCSIStartPool(virConnectPtr conn ATTRIBUTE_UNUSED,
>                                                NULL, NULL) < 0)
>              goto cleanup;
>  
> +        if (virStorageBackendISCSISetAuth(portal, conn, pool->def) < 0)
> +            goto cleanup;
> +
>          if (virStorageBackendISCSIConnection(portal,
>                                               pool->def->source.initiator.iqn,
>                                               pool->def->source.devices[0].path,
>