On 11/23/2016 9:17 AM, Dan Jurgens wrote: > From: Daniel Jurgens <dani...@mellanox.com> > > Infiniband applications access HW from user-space -- traffic is generated > directly by HW, bypassing the kernel. Consequently, Infiniband Partitions, > which are associated directly with HW transport endpoints, are a natural > choice for enforcing granular mandatory access control for Infiniband. QPs may > only send or receives packets tagged with the corresponding partition key > (PKey). The PKey is not a cryptographic key; it's a 16 bit number identifying > the partition. > > Every Infiniband fabric is controlled by a central Subnet Manager (SM). The SM > provisions the partitions by assigning each port with the partitions it can > access. In addition, the SM tags each port with a subnet prefix, which > identifies the subnet. Determining which users are allowed to access which > partition keys on a given subnet forms an effective policy for isolating users > on the fabric. Any application that attempts to send traffic on a given subnet > is automatically subject to the policy, regardless of which device and port it > uses. SM software configures the subnet through a privileged Subnet Management > Interface (SMI), which is presented by each Infiniband port. Thus, the SMI > must > also be controlled to prevent unauthorized changes to fabric configuration and > partitioning. > > To support access control for IB partitions and subnet management, security > contexts must be provided for two new types of objects - PKeys and IB ports. > > A PKey label consists of a subnet prefix and a range of PKey values and is > similar to the labeling mechanism for netports. Each Infiniband port can > reside > on a different subnet. So labeling the PKey values for specific subnet > prefixes > provides the user maximum flexibility, as PKey values may be determined > independently for different subnets. There is a single access vector for PKeys > called "access". > > An Infiniband port is labeled by device name and port number. There is a > single > access vector for IB ports called "manage_subnet". > > Because RDMA allows kernel bypass, enforcement must be done during connection > setup. Communication over RDMA requires a send and receive queue, collectively > known as a Queue Pair (QP). A QP must be initialized by privileged system > calls > before it can be used to send or receive data. During initialization the user > must provide the PKey and port the QP will use; at this time access control > can > be enforced. > > Because there is a possibility that the enforcement settings or security > policy can change, a means of notifying the ib_core module of such changes > is required. To facilitate this a generic notification callback mechanism > is added to the LSM. One callback is registered for checking the QP PKey > associations when the policy changes. Mad agents also register a callback, > they cache the permission to send and receive SMPs to avoid another per > packet call to the LSM. > > Because frequent accesses to the same PKey's SID is expected a cache is > implemented which is very similar to the netport cache. > > In order to properly enforce security when changes to the PKey table or > security policy or enforcement occur ib_core must track which QPs are > using which port, pkey index, and alternate path for every IB device. > This makes operations that used to be atomic transactional. > > When modifying a QP, ib_core must associate it with the PKey index, port, > and alternate path specified. If the QP was already associated with > different settings, the QP is added to the new list prior to the > modification. If the modify succeeds then the old listing is removed. If > the modify fails the new listing is removed and the old listing remains > unchanged. > > When destroying a QP the ib_qp structure is freed by the decive specific > driver (i.e. mlx4_ib) if the 'destroy' is successful. This requires storing > security related information in a separate structure. When a 'destroy' > request is in process the ib_qp structure is in an undefined state so if > there are changes to the security policy or PKey table, the security checks > cannot reset the QP if it doesn't have permission for the new setting. If > the 'destroy' fails, security for that QP must be enforced again and its > status in the list is restored. If the 'destroy' succeeds the security info > can be cleaned up and freed. > > There are a number of locks required to protect the QP security structure > and the QP to device/port/pkey index lists. If multiple locks are required, > the safe locking order is: QP security structure mutex first, followed by > any list locks needed, which are sorted first by port followed by pkey > index.
Ack for the IB parts. Do we have a vote on the SELinux parts from the
security people?
> ---
> v2:
> - Use void* blobs in the LSM hooks. Paul Moore
> - Make the policy change callback generic. Yuval Shaia, Paul Moore
> - Squash LSM changes into the patches where the calls are added. Paul Moore
> - Don't add new initial SIDs. Stephen Smalley
> - Squash MAD agent PKey and SMI patches and move logic to IB security. Dan
> Jurgens
> - Changed ib_end_port to ib_port. Paul Moore
> - Changed ib_port access vector from smp to manage_subnet. Paul Moore
> - Added pkey and ib_port details to the audit log. Paul Moore
> - See individual patches for more detail.
>
> v3:
> - ib_port -> ib_endport. Paul Moore
> - use notifier chains for LSM notifications. Paul Moore
> - reorder parameters in hooks to put security blob first. Paul Moore
> - Don't treat device name as untrusted string in audit log. Paul Moore
>
> v4:
> - Added separate AVC callback for LSM notifier. Paul Moore
> - Removed unneeded braces in ocontext_read. Paul Moore
>
> v5:
> - Fix link error when CONFIG_SECURITY is not set. Build Robot
> - Strip issue and Gerrit-Id: Leon Romanovsky
>
> v6:
> - Whitespace and bracket cleanup. James Morris
> - Cleanup error flow in sel_pkey_sid_slow. James Morris
>
> Daniel Jurgens (9):
> IB/core: IB cache enhancements to support Infiniband security
> IB/core: Enforce PKey security on QPs
> selinux lsm IB/core: Implement LSM notification system
> IB/core: Enforce security on management datagrams
> selinux: Create policydb version for Infiniband support
> selinux: Allocate and free infiniband security hooks
> selinux: Implement Infiniband PKey "Access" access vector
> selinux: Add IB Port SMP access vector
> selinux: Add a cache for quicker retreival of PKey SIDs
>
> drivers/infiniband/core/Makefile | 3 +-
> drivers/infiniband/core/cache.c | 57 ++-
> drivers/infiniband/core/core_priv.h | 115 ++++++
> drivers/infiniband/core/device.c | 86 +++++
> drivers/infiniband/core/mad.c | 52 ++-
> drivers/infiniband/core/security.c | 709
> +++++++++++++++++++++++++++++++++++
> drivers/infiniband/core/uverbs_cmd.c | 20 +-
> drivers/infiniband/core/verbs.c | 27 +-
> include/linux/lsm_audit.h | 15 +
> include/linux/lsm_hooks.h | 35 ++
> include/linux/security.h | 50 +++
> include/rdma/ib_mad.h | 4 +
> include/rdma/ib_verbs.h | 49 +++
> security/Kconfig | 9 +
> security/lsm_audit.c | 16 +
> security/security.c | 59 +++
> security/selinux/Makefile | 2 +-
> security/selinux/hooks.c | 86 ++++-
> security/selinux/ibpkey.c | 245 ++++++++++++
> security/selinux/include/classmap.h | 4 +
> security/selinux/include/ibpkey.h | 31 ++
> security/selinux/include/objsec.h | 11 +
> security/selinux/include/security.h | 7 +-
> security/selinux/selinuxfs.c | 2 +
> security/selinux/ss/policydb.c | 129 ++++++-
> security/selinux/ss/policydb.h | 27 +-
> security/selinux/ss/services.c | 81 ++++
> 27 files changed, 1886 insertions(+), 45 deletions(-)
> create mode 100644 drivers/infiniband/core/security.c
> create mode 100644 security/selinux/ibpkey.c
> create mode 100644 security/selinux/include/ibpkey.h
>
--
Doug Ledford <dledf...@redhat.com>
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