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2014-09-10Documentation: filter: Add MIPS to architectures with BPF JITMarkos Chandras
MIPS supports BPF JIT since v3.16-rc1 Cc: Randy Dunlap <rdunlap@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Daniel Borkmann <dborkman@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-02net: filter: split 'struct sk_filter' into socket and bpf partsAlexei Starovoitov
clean up names related to socket filtering and bpf in the following way: - everything that deals with sockets keeps 'sk_*' prefix - everything that is pure BPF is changed to 'bpf_*' prefix split 'struct sk_filter' into struct sk_filter { atomic_t refcnt; struct rcu_head rcu; struct bpf_prog *prog; }; and struct bpf_prog { u32 jited:1, len:31; struct sock_fprog_kern *orig_prog; unsigned int (*bpf_func)(const struct sk_buff *skb, const struct bpf_insn *filter); union { struct sock_filter insns[0]; struct bpf_insn insnsi[0]; struct work_struct work; }; }; so that 'struct bpf_prog' can be used independent of sockets and cleans up 'unattached' bpf use cases split SK_RUN_FILTER macro into: SK_RUN_FILTER to be used with 'struct sk_filter *' and BPF_PROG_RUN to be used with 'struct bpf_prog *' __sk_filter_release(struct sk_filter *) gains __bpf_prog_release(struct bpf_prog *) helper function also perform related renames for the functions that work with 'struct bpf_prog *', since they're on the same lines: sk_filter_size -> bpf_prog_size sk_filter_select_runtime -> bpf_prog_select_runtime sk_filter_free -> bpf_prog_free sk_unattached_filter_create -> bpf_prog_create sk_unattached_filter_destroy -> bpf_prog_destroy sk_store_orig_filter -> bpf_prog_store_orig_filter sk_release_orig_filter -> bpf_release_orig_filter __sk_migrate_filter -> bpf_migrate_filter __sk_prepare_filter -> bpf_prepare_filter API for attaching classic BPF to a socket stays the same: sk_attach_filter(prog, struct sock *)/sk_detach_filter(struct sock *) and SK_RUN_FILTER(struct sk_filter *, ctx) to execute a program which is used by sockets, tun, af_packet API for 'unattached' BPF programs becomes: bpf_prog_create(struct bpf_prog **)/bpf_prog_destroy(struct bpf_prog *) and BPF_PROG_RUN(struct bpf_prog *, ctx) to execute a program which is used by isdn, ppp, team, seccomp, ptp, xt_bpf, cls_bpf, test_bpf Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-02net: filter: rename sk_chk_filter() -> bpf_check_classic()Alexei Starovoitov
trivial rename to indicate that this functions performs classic BPF checking Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-11net: filter: document internal instruction encodingAlexei Starovoitov
This patch adds a description of eBPFs instruction encoding in order to bring the documentation in line with the implementation. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-11net: filter: mention eBPF terminology as wellAlexei Starovoitov
Since the term eBPF is used anyway on mailing list discussions, lets also document that in the main BPF documentation file and replace a couple of occurrences with eBPF terminology to be more clear. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-11net: filter: cleanup A/X name usageAlexei Starovoitov
The macro 'A' used in internal BPF interpreter: #define A regs[insn->a_reg] was easily confused with the name of classic BPF register 'A', since 'A' would mean two different things depending on context. This patch is trying to clean up the naming and clarify its usage in the following way: - A and X are names of two classic BPF registers - BPF_REG_A denotes internal BPF register R0 used to map classic register A in internal BPF programs generated from classic - BPF_REG_X denotes internal BPF register R7 used to map classic register X in internal BPF programs generated from classic - internal BPF instruction format: struct sock_filter_int { __u8 code; /* opcode */ __u8 dst_reg:4; /* dest register */ __u8 src_reg:4; /* source register */ __s16 off; /* signed offset */ __s32 imm; /* signed immediate constant */ }; - BPF_X/BPF_K is 1 bit used to encode source operand of instruction In classic: BPF_X - means use register X as source operand BPF_K - means use 32-bit immediate as source operand In internal: BPF_X - means use 'src_reg' register as source operand BPF_K - means use 32-bit immediate as source operand Suggested-by: Chema Gonzalez <chema@google.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Chema Gonzalez <chema@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/bonding/bond_alb.c drivers/net/ethernet/altera/altera_msgdma.c drivers/net/ethernet/altera/altera_sgdma.c net/ipv6/xfrm6_output.c Several cases of overlapping changes. The xfrm6_output.c has a bug fix which overlaps the renaming of skb->local_df to skb->ignore_df. In the Altera TSE driver cases, the register access cleanups in net-next overlapped with bug fixes done in net. Similarly a bug fix to send ALB packets in the bonding driver using the right source address overlaps with cleanups in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-23net: filter: doc: add section for BPF test suiteDaniel Borkmann
Mention the recently added test suite in the documentation file. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-22net: doc: Update references to skb->rxhashTobias Klauser
In commit 61b905da33 ("net: Rename skb->rxhash to skb->hash"), skb->rxhash was renamed to skb->hash. Update references in Documentation accordingly. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-04net: filter: doc: expand and improve BPF documentationAlexei Starovoitov
In particular, this patch tries to clarify internal BPF calling convention and adds internal BPF examples, JIT guide, use cases. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22filter: added BPF random opcodeChema Gonzalez
Added a new ancillary load (bpf call in eBPF parlance) that produces a 32-bit random number. We are implementing it as an ancillary load (instead of an ISA opcode) because (a) it is simpler, (b) allows easy JITing, and (c) seems more in line with generic ISAs that do not have "get a random number" as a instruction, but as an OS call. The main use for this ancillary load is to perform random packet sampling. Signed-off-by: Chema Gonzalez <chema@google.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-31doc: filter: extend BPF documentation to document new internalsAlexei Starovoitov
Further extend the current BPF documentation to document new BPF engine internals. Joint work with Daniel Borkmann. Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11filter: doc: improve BPF documentationDaniel Borkmann
This patch significantly updates the BPF documentation and describes its internal architecture, Linux extensions, and handling of the kernel's BPF and JIT engine, plus documents how development can be facilitated with the help of bpf_dbg, bpf_asm, bpf_jit_disasm. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-17sk-filter: Add ability to lock a socket filter programVincent Bernat
While a privileged program can open a raw socket, attach some restrictive filter and drop its privileges (or send the socket to an unprivileged program through some Unix socket), the filter can still be removed or modified by the unprivileged program. This commit adds a socket option to lock the filter (SO_LOCK_FILTER) preventing any modification of a socket filter program. This is similar to OpenBSD BIOCLOCK ioctl on bpf sockets, except even root is not allowed change/drop the filter. The state of the lock can be read with getsockopt(). No error is triggered if the state is not changed. -EPERM is returned when a user tries to remove the lock or to change/remove the filter while the lock is active. The check is done directly in sk_attach_filter() and sk_detach_filter() and does not affect only setsockopt() syscall. Signed-off-by: Vincent Bernat <bernat@luffy.cx> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!