Managing distributed operating system physical resources

Providing a uniform security model to heterogeneous devices in a distributed computing environment. A method includes storing information about a plurality of device security models, including device credentials. The method further includes storing information about a uniform security model, including access rights for various principals. The method further includes identifying a principal. Based on the identified principal, access is provided to the principal according to the uniform security model, based on the device security model credentials.

BACKGROUND

Background and Relevant Art

Further, computing system functionality can be enhanced by a computing systems ability to be interconnected to other computing systems via network connections. Network connections may include, but are not limited to, connections via wired or wireless Ethernet, cellular connections, or even computer to computer connections through serial, parallel, USB, or other connections. The connections allow a computing system to access services at other computing systems and to quickly and efficiently receive application data from other computing system.

The connections allow a computing system to access services at other computing systems and to quickly and efficiently receive application data from other computing systems. Further, interconnected computing systems can be used to implement cluster computing systems where several discrete systems work together to accomplish a computing task assigned to the cluster as a whole. Some such systems may have all, or a portion of the cluster deployed in the cloud. Cloud computing allows for computing resources to be provided as services rather than a deliverable product. In particular, computing power, software, information, etc. are provided (for example, through a rental agreement) over a network, such as the Internet.

A conventional operating system manages resources inside a single physical machine. A distributed operating system can manage resources beyond single physical machine boundaries, such as for example, large pools of physical resources and virtual resources (e.g., physical machines, virtual machines, terminal consoles, switches, power distribution units, etc). For example, a cloud computing environment may implement a distributed operating system to manage cloud computing resources.

When a distributed operating system is deployed in or across datacenters, it relies on the correct configuration of devices managing the datacenters. Sometimes, configuration of those devices is handed off to the distributed operating system, either fully or partially, to support the datacenter architecture and growth. The distributed operating system may manage the configuration solely (i.e., all the configuration is managed by distributed operating system) or partially (i.e., only parts of the configuration are managed by the distributed operating system).

This creates a set of distinct problems for managing datacenter devices, such as power distribution units, terminal consoles, datacenter routers, datacenter switches, etc. First, a configuration/usage conflict may occur when both distributed operating system and humans try to access the same underlying devices. For example, usage of the terminal services console to a recover physical node by a datacenter operation may interfere with the usage of this console by the distributed operating system to attempt some operation on the node. Second, the authorization and authentication model may be broken as users possessing administrative rights or performing equivalent operations on the underlying physical devices are effectively overriding the distributed operating system security model. Third, a rogue user may use underlying datacenter devices as a security hole into the distributed operating system by using a permission model defined on a datacenter device to circumvent a different permission model defined for the distributed operating system. Finally, the auditing model may be broken, as device auditing occurs independently from the rest of the datacenter resources managed by the distributed operating system. Each of these issues may be related to the fact that data devices typically implement a very simple security model, for example, if a user knows the password for a device, they can do anything; if they do not, they cannot do anything.

BRIEF SUMMARY

One embodiment disclosed herein is directed to a method of providing a uniform security model to heterogeneous devices in a distributed computing environment. The method includes storing information about a plurality of devices. The device security model includes credentials for accessing one or more devices. The method further includes storing information about a uniform security model. The uniform security model defines what access rights various principals have to the one or more devices. The method further includes identifying a principal. Based on the identified principal, the method further includes providing access to the identified principal according to the uniform security model by using one or more stored credentials from the device security models.

DETAILED DESCRIPTION

Embodiments may include an agent that mediates all management access to devices in a distributed cloud environment. The devices typically implement a very simple security model, for example, if a user knows the password, they can do anything; if they do not, they cannot do anything. However, some embodiments described herein implement a system with an agent that implements more granular access controls. For example, Members of the XYZ group can only read the status of a device, while members of the ABC group can make some targeted updates, and members of the DEF group can make any change to the device but cannot do so bypassing an audit log that says who did what and when.

The agent in this case has sole possession of the password (or other credentials recognized by the device), and it authenticates incoming requests, validates whether the requests are allowed by an access policy or security model, and if so the agent requests that the device perform the operation using the credentials that it holds.

Embodiments may implement various features and/or functionality. For example, the agent may keep a log of all operations performed. The agent may have sole access to the credentials used to access devices. The agent may obtain sole access to the credentials by updating the credentials on the device to a value the agent chooses and does not divulge, except in limited circumstances, the credentials to any third party. The agent can divulge the credentials to a properly authenticated requestor, but after doing so the agent considers the credentials compromised and subsequently updates the credentials on the device to a value the agent chooses and does not divulge the updated credentials, except in limited circumstances, to any third party. The agent may be able to perform some series of operations on behalf of a requestor where it would not be willing to perform them individually in order to maintain some invariant in the state of the device. The agent may be able to implement separation of duty by only performing some operation if requested by one requestor and having the operation confirmed by a second different requestor. A single entity can be an agent for multiple devices where the access policies for the various devices are all the same. A single entity can be an agent for multiple devices where the access policies for the various devices are different. The agent may periodically poll the state of a device, compare it to the expected state, and trigger an alarm if they differ.

Referring now toFIG. 1, an example agent100is illustrated.FIG. 1illustrates that some embodiments may implement protected devices102, which could be, for example, a managed datacenter power distribution unit, router, switch, terminal server, etc. Embodiments may include a distributed operating system104that manages access to and protects datacenter devices102using the agent100, needed for the operation of the distributed operating system or software running on top of it. The agent100may include abstract permissions, authentication, authorization, and auditing models for the protected devices102. The distributed operating system104may provide auditing for protected device operations outside of the device boundaries. The agent100may manage the device version and configuration to restrict external access to the devices102. Access and management is performed by the agent100. The agent100may provide management access to underlying resources (e.g., network devices).

A distributed cloud operating system, or distributed operating system as used herein is a system allowing allocation of datacenter resources (VMs, IP addresses, etc) and providing a platform for execution of the software across datacenter with high redundancy, running in multiple instances and fault domains.

Embodiments may be implemented where a distributed operating system104is the sole owner of the devices102it manages, using the agent100. Ordinarily, Managed devices102would be able to be accessed by user106directly (such as through path108to the device102-1). However, embodiments may prevent this from occurring by the agent100controlling the password or other credentials to the device102-1and keeping the credentials secret from the user106. The agent100can provide outside access through the distributed operating system104(such as through path110to the device102-1). Providing access through the distributed operating system104may be implemented by the agent100managing the keys of the devices102and/or username/password access needed to access the devices, thus not allowing a direct connection to the devices, as the keys of the devices are not directly exposed by the distributed operating system.

The following illustrates an example. When a network resource is added to the datacenter, a “buildout” process occurs. During the buildout process, firmware is upgraded and baseline configuration is enforced for the device. Additionally, a device identification key is generated. The private key portion of the device identification key is stored on the device while the public key portion of the device identification key is stored in the distributed operating system central storage114. The device key is used to validate that the device being connected to is the right device and not an imposter.

Once trust between the device and agent100is created, it is managed by the agent100. In some embodiments rotating key operations and credential creation operations may be performed. This can be done as a security measure to guard against compromised credentials.

For rotating key operations for the device, the agent100may ask the device to renew the keys and share the public key or renew the keys for the devices and update them. This may occur over existing secure channels. Creating credentials on the device that will be used to identify the connections from the distributed operating system may involve the agent100connecting to the device directly either for service provisioning needs (as illustrated by the path116from an application112to a device102-1) or on behalf of the end user106(as illustrated by the path110to the device102-1).

Referring now toFIG. 2, additional details are illustrated. In particular,FIG. 2illustrates a stack200including a hardware stack202and a software stack204illustrating various details.FIG. 2illustrates a user106that in this example is a human user. The user106interacts with a management station208.FIG. 2also illustrates in the hardware stack202a set of nodes210or physical machines running the distributed operating system104(seeFIG. 1).FIG. 2further illustrates in the hardware stack202managed devices102.

In the software stack204,FIG. 2illustrates a datacenter management client212run by the management station208and controlled by the user106.

FIG. 2illustrates various software components run on the nodes210running the distributed cloud operating system. These components include a distributed operating system datacenter manager214, a device credential manager216, a device access proxy218, a hardware abstraction layer220, and a set of per device drivers222(illustrated specifically at222-1,222-2through222-n). The nodes210running the distributed operating system may also include uniform security model store224and a device security model store226. These stores store policy information such as user policies, access restrictions, permissions, and the like for users and applications using the distributed operating system104and the devices respectively. These will be discussed in more detail below.

The distributed operating system datacenter manager214includes functionality for interacting with the datacenter management client212and interacting with the device credential manager216, the device access proxy218, and the hardware abstraction layer220to control principal access to the datacenter devices102through the device drivers222. For example, the device access proxy218, device credential manager216and the hardware abstraction layer220can translate one or more uniform security model claims from the uniform security model store224to one or more device security model claims from the device security model store226to provide access to principals (such as users106or applications212) to the plurality of distributed system devices102using the per device type drivers222and the embedded management software228based on the device security model claims.

The software stack also includes a set of device management software228embedded in each device in the set of devices102(e.g. device management software228-1,228-2and228-3). Each of the devices in the set of devices102includes device management software or firmware embedded in the device to allow a principal to access, manage, and/or control the device. While this access, management and/or control can traditionally be performed independently using interfaces in the device management software228,FIG. 2illustrates that the distributed operating system104can be configured to make use of the device management software228, such that access is routed through the distributed operating system104, and to prevent direct connection by a user to the device. This allows for the distributed operating system104to control and manage access, provide conflict resolution, using an agent100as illustrated inFIG. 1, as different principals try to access a particular device, provide logging functionality, etc. Additional details are illustrated below.

Device Management Model Abstraction

Embodiments may be implemented by abstracting common operations from the datacenter devices102. In some embodiments, common operations executed by principals (such as software modules) in the distributed operating system104, as well by external principals (such as end users106), are given as commands to the agent100and executed on behalf of the principals. Various examples are now illustrated.

Some embodiments may implement devices102that are power distribution units. Power distribution units can be used to power-on/power-off dormant nodes (physical server), restart nodes (physical server), get power status of the server, etc.

Some embodiments may implement devices102that are serial terminal servers. Serial terminal servers issue commands on a management console for a specific server, enter serial management interfaces, capture serial output, etc.

Some embodiments may implement devices102that are switches, routers, firewalls, other intrusion detection systems, etc. This may include adding network configuration for a device's port configuration, changing networking configuration for a device (VLANs, routes), etc.

Devices added to the system may have an associated hardware abstraction layer driver to present a basic set of capabilities of the device. Additional capabilities can be configured through a buildout process and managed manually. Alternatively, capabilities can be managed using tools implemented outside of the basic abstraction model. Thus, a collection of drivers for the devices in the datacenter creates an abstraction layer for non-uniform device management.

Permissions Model

While operating in the model described above, auditing may be implemented by the distributed operating system, which (using the device access proxy218) proxies the calls to the datacenter's devices102and audits them externally, thus obviating any need for configuring auditing for mainline scenarios. Thus, there is less risk that the auditing can be circumvented, as the auditing mechanisms are fully external to the devices102.

The permissions model, in the illustrated example, is also defined by the distributed operating system at the device credential manager216. For example, administrators with sufficient access levels defined to a specific node or rack can execute operations on the permissions model, rather than all the administrators having access to the specific datacenter infrastructure device.

Baseline Monitoring and RMA Process

Embodiments may provide administrative access to the devices102, thus the agent100can perform validation and backup of the configuration as a result of the user management operations and distributed operating system changes to the configuration. Furthermore, if a device is broken or destroyed, a replacement device can apply the same configuration and start the operation in place instead of the faulty device.

Embodiments may include functionality for backing up security information and device configuration as a part of the distributed operating system configuration. A distributed operating system configuration is accurate at some point of time. A checkpoint can be created to store configuration details at this point in time. Thus, underlying managed devices' assumed configurations will be checkpointed and backed up as a part of the operating system checkpoint backup. However, secret keys to access a device need to match in the distributed operating system and the device.

However, restored operating system configurations and/or the restored device configurations are not guaranteed to be restored to the exact synchronized state due to clock differences, incomplete configuration operations, etc. Thus, transactions may be applied when configuring the device and current/previous configurations may be saved and matched during restore. For example, the key replacement operation might have succeeded in the distributed operating system, but was not saved in the device due to power outage. Thus, the powered up device may need to be accessed with the previous key.

Key Rotation

Embodiments may include frequent secret rotation on the managed devices102. This can be done to minimize damage occurring from compromised keys.

Emergency Access

Embodiments include functionality to account for emergency access to underlying datacenter devices102when parts of the distributed operating system104or agent100are malfunctioning or network access is partially or fully down. In these instances the management through the distributed operating system mechanisms may be difficult or impossible. Embodiments may include a process to extract device secrets from the distributed operating system device policy store226, which includes a device secret store. Extracting the key from the distributed operating system secret store allows for using the key for some time until the distributed operating system102is back online. However, in the moment when the key is extracted from the operating system secret store it is marked as “invalid”. When the distributed operating system is back online, the extracted keys marked invalid are rotated on all the relevant managed devices102.

Referring now toFIG. 3, a method300is illustrated. The method300includes acts for providing a uniform security model to heterogeneous devices in a distributed computing environment. The method300includes storing information about a plurality of device security models (act302). For example,FIG. 2illustrates a device security model store226. The device security model store226may include credentials needed to access one or more devices102. The device security model may include other information such as required permissions, device limitations, device restrictions, etc. For example, devices may limit the number of principals that can connect to a device at any given time. This information may be stored on the device security model store226. Other information that may be stored in the device security model store226may include certificates, passwords, configuration exceptions, special access lists, special networking configuration, etc.

The method300further includes storing information about a uniform security model (act304). For example,FIG. 2illustrates a uniform security model store224. The uniform security model may define what access rights various principals have to the one or more devices. The uniform security model store224may include principal policy information. For example, the uniform security model store224could be role based restrictions. For example, certain roles may be restricted to accessing devices102only at specific times, for limited amounts of time, etc. Alternatively or additionally, certain roles may be restricted from accessing certain devices. Certain roles could have access to all devices. Certain roles could have the ability to pre-empt access over other roles. Policies could be in place that restricts access to all or certain sets of principals to limited periods. Various other policies, though not enumerated here, could be stored at the uniform security model store224.

The method300further includes identifying a principal (act306). For example, embodiments may identify a user106or software module112that wants to access a device. This may be due to the principal sending a device access request through the agent100. Such a request may be initiated by using various software APIs, user interfaces, etc.

The method300further includes based on the identified principal, provide access to the identified principal according to the uniform security model by using the device security model (act308). For example, as a result of a user106requesting access to a device, uniform security model claims may be generated or invoked based on policies stored in the uniform security model store224. The agent100may use device security model credentials to request access to devices to allow access by a user104or application112to a device102-1according to the uniform security model.

The method300may be practiced where the plurality of device security models comprise device secrets. For example, the device secrets may include passwords, certificates, or the like.

The method300may be practiced where the uniform security model is a distributed operating system security model. In particular, a distributed operating system, that may manage resources beyond single physical machine boundaries (such as for example, large pools of physical resources and virtual resources system), could have a security model which may have various access restrictions and/or policies.

In some embodiments, the distributed operating system may be implemented in a cloud computing environment.

The method300may be practiced where the uniform security model comprises principal access restrictions and/or time-based access restrictions. For example, certain roles may be restricted to accessing devices only at specific times, for limited amounts of time, etc. Alternatively or additionally, certain roles may be restricted from accessing certain devices. Certain roles could have access to all devices. Certain roles could have the ability to pre-empt access over other roles. Polices could be in place the restricts access to all or certain sets of principals to limited periods

The method300may further include identifying conflicting access requests by different principals to one or more devices and arbitrating such conflicting access requests. For example, the conflicting access requests may include a plurality of end users requesting conflicting access to one or more devices. Alternatively or additionally, the conflicting access requests may include a plurality of software principals requesting conflicting access to one or more devices. Alternatively or additionally, conflicting access requests comprise at least one software principal and one end user requesting conflicting access to one or more devices. For example, various combinations of principals may request access to devices102through the agent100. Such combinations may include combinations of end users, such as end user106or software principals such as the application112. Embodiments may have decision engines and rules, or other functionality, for determining how conflicting accesses are resolved.

Further, upon reaching various computer system components, program code means in the form of computer-executable instructions or data structures can be transferred automatically from transmission computer readable media to physical computer readable storage media (or vice versa). For example, computer-executable instructions or data structures received over a network or data link can be buffered in RAM within a network interface module (e.g., a “NIC”), and then eventually transferred to computer system RAM and/or to less volatile computer readable physical storage media at a computer system. Thus, computer readable physical storage media can be included in computer system components that also (or even primarily) utilize transmission media.