bpf: Use static initializers

MFC after: 1 week

ifnet: Detach BPF descriptors on interface vmove event

When an interface is moving to/from a vnet jail, it may still have BPF
descriptors attached. The userland (e.g. tcpdump) does not get noticed
t

ifnet: Detach BPF descriptors on interface vmove event

When an interface is moving to/from a vnet jail, it may still have BPF
descriptors attached. The userland (e.g. tcpdump) does not get noticed
that the interface is departing and still opens BPF descriptors thus
may result in leaking sensitive traffic (e.g. an interface is moved
back to parent jail but a user is still sniffing traffic over it in
the child jail).

Detach BPF descriptors so that the userland will be signaled.

Reviewed by: ae
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D45727

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bpf: Fix potential race conditions

There're two possible race conditions,

1. Concurrent bpfattach() and bpf_setif(), i.e., BIOCSETIF ioctl,
2. Concurrent bpfdetach() and bpf_setif().

For the first

bpf: Fix potential race conditions

There're two possible race conditions,

1. Concurrent bpfattach() and bpf_setif(), i.e., BIOCSETIF ioctl,
2. Concurrent bpfdetach() and bpf_setif().

For the first case, userland may see BPF interface attached but it has
not been in the attached interfaces list `bpf_iflist` yet. Well it
will eventually be so this case does not matter.

For the second one, bpf_setif() may reference `dead_bpf_if` and the
kernel will panic (spotted by change [1], without the change we will
end up silently corrupted memory).

A simple fix could be that, we add additional check for `dead_bpf_if`
in the function `bpf_setif()`. But that requires to extend protection
of global lock (BPF_LOCK), i.e., BPF_LOCK should also protect the
assignment of `ifp->if_bpf`. That simple fix works but is apparently
not a good design. Since the attached interfaces list `bpf_iflist` is
the single source of truth, we look through it rather than check
against the interface's side, aka `ifp->if_bpf`.

This change has performance regression, that the cost of BPF interface
attach operation (BIOCSETIF ioctl) goes back from O(1) to O(N) (where
N is the number of BPF interfaces). Well we normally have sane amounts
of interfaces, an O(N) should be affordable.

[1] 7a974a649848 bpf: Make dead_bpf_if const

Fixes: 16d878cc99ef Fix the following bpf(4) race condition ...
MFC after: 4 days
Differential Revision: https://reviews.freebsd.org/D45725

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kern: Make fileops and filterops tables const where possible

No functional change intended.

MFC after: 1 week

bpf: Some style and white space cleanup

MFC after: 3 days

bpf: Update a comment

This comment was introduced by fix [1], later the fix was refined by
change [2], and the context of the usage of `m_get2()` and `m_getjcl()`
got lost, then the comment became o

bpf: Update a comment

This comment was introduced by fix [1], later the fix was refined by
change [2], and the context of the usage of `m_get2()` and `m_getjcl()`
got lost, then the comment became obscure.

Update to reflect the current behavior.

1. f13da24715a7 net/bpf: Fix writing of buffer bigger than PAGESIZE
2. a051ca72e281 Introduce m_get3()

Fixes: a051ca72e281 Introduce m_get3()
MFC after: 3 days

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bpf: Prefer the boolean form when calling bpf_peers_present()

No functional change intended.

Reviewed by: markj, kp, #network
MFC with: 8f31b879ecaf
Differential Revision: https://reviews.freebsd.o

bpf: Prefer the boolean form when calling bpf_peers_present()

No functional change intended.

Reviewed by: markj, kp, #network
MFC with: 8f31b879ecaf
Differential Revision: https://reviews.freebsd.org/D45509

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sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl s

sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

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bpf: Make dead_bpf_if const

The dead_bpf_if is not subjected to be written. Make it const so that
on destructive writing to it the kernel will panic instead of silent
memory corruption.

No function

bpf: Make dead_bpf_if const

The dead_bpf_if is not subjected to be written. Make it const so that
on destructive writing to it the kernel will panic instead of silent
memory corruption.

No functional change intended.

Reviewed by: markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D42189

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bpf: Add IfAPI analogue for bpf_peers_present()

An interface's bpf could feasibly not exist, in which case
bpf_peers_present() would panic from a NULL pointer dereference. Solve
this by adding a ne

bpf: Add IfAPI analogue for bpf_peers_present()

An interface's bpf could feasibly not exist, in which case
bpf_peers_present() would panic from a NULL pointer dereference. Solve
this by adding a new IfAPI that could deal with a NULL bpf, if such
could occur in the network stack.

Reviewed by: zlei
Sponsored by: Juniper Networks, Inc.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D42082

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Revert "bpf: Add IfAPI analogue for bpf_peers_present()"

This reverts commit c81dd8e5fe72d0c7ec055c8621bb2da3a3627abf.

Commit message needs revised.

bpf: Add IfAPI analogue for bpf_peers_present()

An interface's bpf could feasibly not exist, in which case
bpf_peers_present() would panic from a NULL pointer dereference. Solve
this by adding a ne

bpf: Add IfAPI analogue for bpf_peers_present()

An interface's bpf could feasibly not exist, in which case
bpf_peers_present() would panic from a NULL pointer dereference. Solve
this by adding a new IfAPI that includes a NULL check. Since this API
is used in only a handful of locations, it reduces the the NULL check
scope over inserting the check into bpf_peers_present().

Sponsored by: Juniper Networks, Inc.
MFC after: 1 week

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sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

net: whack __mips__ leftovers

Sponsored by: Rubicon Communications, LLC ("Netgate")

bpf: Add missing NOP stubs

This fixes kernel build with nodevice bpf [1].

[1] https://lists.freebsd.org/archives/freebsd-current/2023-February/003178.html

Reported by: Gary Jennejohn <garyj@gmx.de

bpf: Add missing NOP stubs

This fixes kernel build with nodevice bpf [1].

[1] https://lists.freebsd.org/archives/freebsd-current/2023-February/003178.html

Reported by: Gary Jennejohn <garyj@gmx.de>
Reviewed by: jhibbits
Fixes: 950cc1f44fbd bpf: Add "_if" tap APIs
Differential Revision: https://reviews.freebsd.org/D38432

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bpf: Add "_if" tap APIs

Summary:
Hide more netstack by making the BPF_TAP macros real functions in the
netstack. "struct ifnet" is used in the header instead of "if_t" to
keep header pollution down

bpf: Add "_if" tap APIs

Summary:
Hide more netstack by making the BPF_TAP macros real functions in the
netstack. "struct ifnet" is used in the header instead of "if_t" to
keep header pollution down.

Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D38103

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ifnet/API: Move struct ifnet definition to a <net/if_private.h>

Hide the ifnet structure definition, no user serviceable parts inside,
it's a netstack implementation detail. Include it temporarily

ifnet/API: Move struct ifnet definition to a <net/if_private.h>

Hide the ifnet structure definition, no user serviceable parts inside,
it's a netstack implementation detail. Include it temporarily in
<net/if_var.h> until all drivers are updated to use the accessors
exclusively.

Reviewed by: glebius
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D38046

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bpf: only access refcounts using dedicated primitives

Sponsored by: Rubicon Communications, LLC ("Netgate")

bpf: obtain timestamps from controller via pkthdr if available

r325506 (3cf8254f1ea9) extended struct pkthdr to add packet timestamp in
mbuf(9) chain. For example, cxgbe(4) and mlx5en(4) support th

bpf: obtain timestamps from controller via pkthdr if available

r325506 (3cf8254f1ea9) extended struct pkthdr to add packet timestamp in
mbuf(9) chain. For example, cxgbe(4) and mlx5en(4) support this feature.
Use the timestamp for bpf(4) if it is available.

Reviewed by: hselasky, kib, np
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D36868

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bpf: Fix BIOCPROMISC locking

BPF might put an interface in promiscuous mode when handling the
BIOCSDLT ioctl. When this happens, a flag is set in the BPF descriptor
so that the old interface can be

bpf: Fix BIOCPROMISC locking

BPF might put an interface in promiscuous mode when handling the
BIOCSDLT ioctl. When this happens, a flag is set in the BPF descriptor
so that the old interface can be restored when the BPF descriptor is
destroyed.

The BIOCPROMISC ioctl can also be used to put a BPF descriptor's
interface into promiscuous mode, but there was nothing synchronizing the
flag. Fix this by modifying the ioctl handler to acquire the global BPF
mutex, which is used to synchronize ifpromisc() calls elsewhere in BPF.

Reviewed by: kp, melifaro
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D36045

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bpf: Zero pad bytes preceding BPF headers

BPF headers are word-aligned when copied into the store buffer. Ensure
that pad bytes following the preceding packet are cleared.

Reported by: KMSAN
MFC a

bpf: Zero pad bytes preceding BPF headers

BPF headers are word-aligned when copied into the store buffer. Ensure
that pad bytes following the preceding packet are cleared.

Reported by: KMSAN
MFC after: 1 week
Sponsored by: The FreeBSD Foundation

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bpf: Fix the write filter for detached descriptors

A BPF descriptor only has an associated interface descriptor once it is
attached to an interface, e.g., with BIOCSETIF. Avoid dereferencing a
NULL

bpf: Fix the write filter for detached descriptors

A BPF descriptor only has an associated interface descriptor once it is
attached to an interface, e.g., with BIOCSETIF. Avoid dereferencing a
NULL pointer in filt_bpfwrite() if the BPF descriptor is not attached.

Reviewed by: ae
Reported by: syzbot+ae45d5166afe15a5a21d@syzkaller.appspotmail.com
Fixes: ded77e0237a8 ("Allow the BPF to be select for write.")
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D32561

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Allow the BPF to be select for write. This is needed for boost:asio
which otherwise fails to handle BPFs.
Reviewed by: ae
Differential Revision: https://reviews.freebsd.org/D31967

Introduce m_get3()

Introduce m_get3() which is similar to m_get2(), but can allocate up to
MJUM16BYTES bytes (m_get2() can only allocate up to MJUMPAGESIZE).

This simplifies the bpf improvement in

Introduce m_get3()

Introduce m_get3() which is similar to m_get2(), but can allocate up to
MJUM16BYTES bytes (m_get2() can only allocate up to MJUMPAGESIZE).

This simplifies the bpf improvement in f13da24715.

Suggested by: glebius
Differential Revision: https://reviews.freebsd.org/D31455

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vlan: deduplicate bpf_setpcp() and pf_ieee8021q_setpcp()

These two fuctions were identical, so move them into the common
vlan_set_pcp() function, exposed in the if_vlan_var.h header.

Reviewed by: d

vlan: deduplicate bpf_setpcp() and pf_ieee8021q_setpcp()

These two fuctions were identical, so move them into the common
vlan_set_pcp() function, exposed in the if_vlan_var.h header.

Reviewed by: donner
MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D31275

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