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* [PATCH v7 net-next 0/6] net: Add bpf support for sockets
@ 2016-12-01 16:48 David Ahern
  2016-12-01 16:48 ` [PATCH v7 net-next 1/6] bpf: Refactor cgroups code in prep for new type David Ahern
                   ` (7 more replies)
  0 siblings, 8 replies; 15+ messages in thread
From: David Ahern @ 2016-12-01 16:48 UTC (permalink / raw)
  To: netdev; +Cc: daniel, ast, daniel, maheshb, tgraf, David Ahern

The recently added VRF support in Linux leverages the bind-to-device
API for programs to specify an L3 domain for a socket. While
SO_BINDTODEVICE has been around for ages, not every ipv4/ipv6 capable
program has support for it. Even for those programs that do support it,
the API requires processes to be started as root (CAP_NET_RAW) which
is not desirable from a general security perspective.

This patch set leverages Daniel Mack's work to attach bpf programs to
a cgroup to provide a capability to set sk_bound_dev_if for all
AF_INET{6} sockets opened by a process in a cgroup when the sockets
are allocated.

For example:
 1. configure vrf (e.g., using ifupdown2)
        auto eth0
        iface eth0 inet dhcp
            vrf mgmt

        auto mgmt
        iface mgmt
            vrf-table auto

 2. configure cgroup
        mount -t cgroup2 none /tmp/cgroupv2
        mkdir /tmp/cgroupv2/mgmt
        test_cgrp2_sock /tmp/cgroupv2/mgmt 15

 3. set shell into cgroup (e.g., can be done at login using pam)
        echo $$ >> /tmp/cgroupv2/mgmt/cgroup.procs

At this point all commands run in the shell (e.g, apt) have sockets
automatically bound to the VRF (see output of ss -ap 'dev == <vrf>'),
including processes not running as root.

This capability enables running any program in a VRF context and is key
to deploying Management VRF, a fundamental configuration for networking
gear, with any Linux OS installation.

This patchset also exports the socket family, type and protocol as
read-only allowing bpf filters to deny a process in a cgroup the ability
to open specific types of AF_INET or AF_INET6 sockets.

v7
- comments from Alexei

v6
- add export of socket family, type and protocol


David Ahern (6):
  bpf: Refactor cgroups code in prep for new type
  bpf: Add new cgroup attach type to enable sock modifications
  samples: bpf: add userspace example for modifying sk_bound_dev_if
  bpf: Add support for reading socket family, type, protocol
  samples/bpf: Update bpf loader for cgroup section names
  samples/bpf: add userspace example for prohibiting sockets

 include/linux/bpf-cgroup.h      | 60 +++++++++++++++++------------
 include/net/sock.h              | 15 ++++++++
 include/uapi/linux/bpf.h        |  9 +++++
 kernel/bpf/cgroup.c             | 43 ++++++++++++++++++---
 kernel/bpf/syscall.c            | 33 +++++++++-------
 net/core/filter.c               | 83 +++++++++++++++++++++++++++++++++++++++++
 net/ipv4/af_inet.c              | 12 +++++-
 net/ipv6/af_inet6.c             |  8 ++++
 samples/bpf/Makefile            |  6 +++
 samples/bpf/bpf_load.c          | 14 +++++--
 samples/bpf/bpf_load.h          |  1 +
 samples/bpf/sock_flags_kern.c   | 44 ++++++++++++++++++++++
 samples/bpf/test_cgrp2_sock.c   | 83 +++++++++++++++++++++++++++++++++++++++++
 samples/bpf/test_cgrp2_sock.sh  | 47 +++++++++++++++++++++++
 samples/bpf/test_cgrp2_sock2.c  | 66 ++++++++++++++++++++++++++++++++
 samples/bpf/test_cgrp2_sock2.sh | 81 ++++++++++++++++++++++++++++++++++++++++
 16 files changed, 559 insertions(+), 46 deletions(-)
 create mode 100644 samples/bpf/sock_flags_kern.c
 create mode 100644 samples/bpf/test_cgrp2_sock.c
 create mode 100755 samples/bpf/test_cgrp2_sock.sh
 create mode 100644 samples/bpf/test_cgrp2_sock2.c
 create mode 100755 samples/bpf/test_cgrp2_sock2.sh

-- 
2.1.4

^ permalink raw reply	[flat|nested] 15+ messages in thread

end of thread, other threads:[~2016-12-02 18:46 UTC | newest]

Thread overview: 15+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-12-01 16:48 [PATCH v7 net-next 0/6] net: Add bpf support for sockets David Ahern
2016-12-01 16:48 ` [PATCH v7 net-next 1/6] bpf: Refactor cgroups code in prep for new type David Ahern
2016-12-01 16:56   ` Alexei Starovoitov
2016-12-01 16:48 ` [PATCH v7 net-next 2/6] bpf: Add new cgroup attach type to enable sock modifications David Ahern
2016-12-01 16:56   ` Alexei Starovoitov
2016-12-01 16:48 ` [PATCH v7 net-next 3/6] samples: bpf: add userspace example for modifying sk_bound_dev_if David Ahern
2016-12-01 16:57   ` Alexei Starovoitov
2016-12-01 16:48 ` [PATCH v7 net-next 4/6] bpf: Add support for reading socket family, type, protocol David Ahern
2016-12-01 16:57   ` Alexei Starovoitov
2016-12-01 16:48 ` [PATCH v7 net-next 5/6] samples/bpf: Update bpf loader for cgroup section names David Ahern
2016-12-01 16:58   ` Alexei Starovoitov
2016-12-01 16:48 ` [PATCH v7 net-next 6/6] samples/bpf: add userspace example for prohibiting sockets David Ahern
2016-12-01 16:58   ` Alexei Starovoitov
2016-12-01 16:59 ` [PATCH v7 net-next 0/6] net: Add bpf support for sockets Alexei Starovoitov
2016-12-02 18:46 ` David Miller

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