From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BBAACC2D0C0 for ; Tue, 24 Dec 2019 00:07:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82CFD20CC7 for ; Tue, 24 Dec 2019 00:07:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="hYtrJkem" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726866AbfLXAHo (ORCPT ); Mon, 23 Dec 2019 19:07:44 -0500 Received: from mail-qt1-f193.google.com ([209.85.160.193]:33731 "EHLO mail-qt1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726833AbfLXAHo (ORCPT ); Mon, 23 Dec 2019 19:07:44 -0500 Received: by mail-qt1-f193.google.com with SMTP id d5so16790838qto.0; Mon, 23 Dec 2019 16:07:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ER+rfJn7cxGGz6d4bPX/W9caKgcBXlgNB2YpDv8z0Ig=; b=hYtrJkemDCEYu3p308KyBFSMixPy0uLFQctHqKAz8AZT8K2jpnOU2c5NivWUwOjHkZ dI0j4OEgflq2en6g7SkwyVrR8OarBhGjXme2ohWXJik7vFggkvOSbVnDXj/4EdZnHTpO bcGUxQIRjsnbJEBGEd9DCFjZAMymy7wmSnO9OF1eQqx6aAl6WFKYoOcS82koRqN7Nk4P gt/+FTTRGQnFf2IbfWbolfRCQMTn5i8Id7pr8swhpr/kfmHXV8aXlYidO08OJOctWaSH BHSzj83f4lziRkwl0fqNtvbVQeOLdPx5ZZ+dr3kYAdj06VYNhkQbpLuQImPdI1E2w3KL LcQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ER+rfJn7cxGGz6d4bPX/W9caKgcBXlgNB2YpDv8z0Ig=; b=Rpy1L+zg3ughSmNliMTzwkdUOT+MjjQjpEKjtdOf4F8KJwuTosVqYHW/blAmcD/e9T xAmZ9OGRovfDvicSLPBLTCnY96Jh1FSD9X2xcN+ud0VZ8VfcsBWj7vnQwXPIaW4Gefzh 3hWgDBdRz1v7rnhRGQNhBsB5HRNcWn4fz+xuZAYuRP5GTfZryb4sYRt0X0GBMkS7SEXm Z4favMeUD0QYayZfXAV4kuk431lN0XTj3fOw3RAY1J0wlfMpgz6zmmAKA4YZprfXq2Pr Rmu838S6hrvsbrPIARQQ81Jz2K9thZqNCkJ+pP9hVI3BOiuwyciE/aCLliHI8hurMR05 2ngw== X-Gm-Message-State: APjAAAUV4OH6UIPzPu9Un07cNyiFF5sxun38ya1FFkeBl00kmmTs9gvk lnokxoMS5BEhnA4P/K47hcN2NQ+tuD31CR706X0= X-Google-Smtp-Source: APXvYqwwZJGEFErh5HO3IHrvWKxOnNjU/j4GnYk7Npcv4DK1qHMJgIAVvHW67Bsqn69H9QCDvUlGYiKxiK9jQ15USjs= X-Received: by 2002:ac8:7b29:: with SMTP id l9mr24415421qtu.141.1577146062462; Mon, 23 Dec 2019 16:07:42 -0800 (PST) MIME-Version: 1.0 References: <20191220154208.15895-1-kpsingh@chromium.org> <20191220154208.15895-6-kpsingh@chromium.org> In-Reply-To: <20191220154208.15895-6-kpsingh@chromium.org> From: Andrii Nakryiko Date: Mon, 23 Dec 2019 16:07:31 -0800 Message-ID: Subject: Re: [PATCH bpf-next v1 05/13] tools/libbpf: Add support in libbpf for BPF_PROG_TYPE_LSM To: KP Singh Cc: open list , bpf , linux-security-module@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , James Morris , Kees Cook , Thomas Garnier , Michael Halcrow , Paul Turner , Brendan Gregg , Jann Horn , Matthew Garrett , Christian Brauner , =?UTF-8?B?TWlja2HDq2wgU2FsYcO8bg==?= , Florent Revest , Brendan Jackman , Martin KaFai Lau , Song Liu , Yonghong Song , "Serge E. Hallyn" , Mauro Carvalho Chehab , "David S. Miller" , Greg Kroah-Hartman , Nicolas Ferre , Stanislav Fomichev , Quentin Monnet , Andrey Ignatov , Joe Stringer Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Fri, Dec 20, 2019 at 7:43 AM KP Singh wrote: > > From: KP Singh > > Update the libbpf library with functionality to load and > attach a program type BPF_PROG_TYPE_LSM, currently with > only one expected attach type BPF_LSM_MAC. > > Signed-off-by: KP Singh > --- > tools/lib/bpf/bpf.c | 2 +- > tools/lib/bpf/bpf.h | 6 +++++ > tools/lib/bpf/libbpf.c | 44 +++++++++++++++++++++-------------- > tools/lib/bpf/libbpf.h | 2 ++ > tools/lib/bpf/libbpf.map | 6 +++++ > tools/lib/bpf/libbpf_probes.c | 1 + > 6 files changed, 43 insertions(+), 18 deletions(-) > > diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c > index 98596e15390f..9c6fb083f7de 100644 > --- a/tools/lib/bpf/bpf.c > +++ b/tools/lib/bpf/bpf.c > @@ -228,7 +228,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, > memset(&attr, 0, sizeof(attr)); > attr.prog_type = load_attr->prog_type; > attr.expected_attach_type = load_attr->expected_attach_type; > - if (attr.prog_type == BPF_PROG_TYPE_TRACING) { > + if (needs_btf_attach(attr.prog_type)) { > attr.attach_btf_id = load_attr->attach_btf_id; > attr.attach_prog_fd = load_attr->attach_prog_fd; > } else { > diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h > index 3c791fa8e68e..df2a00ff349f 100644 > --- a/tools/lib/bpf/bpf.h > +++ b/tools/lib/bpf/bpf.h > @@ -177,6 +177,12 @@ LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, > __u32 *buf_len, __u32 *prog_id, __u32 *fd_type, > __u64 *probe_offset, __u64 *probe_addr); > > +static inline bool needs_btf_attach(enum bpf_prog_type prog_type) > +{ > + return (prog_type == BPF_PROG_TYPE_TRACING || > + prog_type == BPF_PROG_TYPE_LSM); > +} > + This doesn't have to be a public API, right? It also doesn't follow naming conventions of libbpf APIs. Let's just move it into libbpf_internal.h, given it's used in few files. Also, Martin's patches add STRUCT_OPS, which do need btf_attach, but don't set attach_prog_fd. So maybe something like libbpf_need_attach_prog_btf() for a name to be a bit more specific? > #ifdef __cplusplus > } /* extern "C" */ > #endif > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > index b20f82e58989..b0b27d8e5a37 100644 > --- a/tools/lib/bpf/libbpf.c > +++ b/tools/lib/bpf/libbpf.c > @@ -3738,7 +3738,7 @@ load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, > load_attr.insns = insns; > load_attr.insns_cnt = insns_cnt; > load_attr.license = license; > - if (prog->type == BPF_PROG_TYPE_TRACING) { > + if (needs_btf_attach(prog->type)) { > load_attr.attach_prog_fd = prog->attach_prog_fd; > load_attr.attach_btf_id = prog->attach_btf_id; > } else { > @@ -3983,7 +3983,7 @@ __bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, > > bpf_program__set_type(prog, prog_type); > bpf_program__set_expected_attach_type(prog, attach_type); > - if (prog_type == BPF_PROG_TYPE_TRACING) { > + if (needs_btf_attach(prog_type)) { > err = libbpf_find_attach_btf_id(prog->section_name, > attach_type, > attach_prog_fd); > @@ -4933,6 +4933,7 @@ bool bpf_program__is_##NAME(const struct bpf_program *prog) \ > } \ > > BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER); > +BPF_PROG_TYPE_FNS(lsm, BPF_PROG_TYPE_LSM); > BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE); > BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS); > BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT); > @@ -5009,6 +5010,8 @@ static const struct { > BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), > BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), > BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), > + BPF_PROG_BTF("lsm/", BPF_PROG_TYPE_LSM, > + BPF_LSM_MAC), Is is supposed to be attachable same as BPF_PROG_TYPE_TRACING programs? If yes, please define auto-attaching function, similar to SEC_DEF("raw_tp") few lines below this one. > BPF_APROG_SEC("cgroup_skb/ingress", BPF_PROG_TYPE_CGROUP_SKB, > BPF_CGROUP_INET_INGRESS), > BPF_APROG_SEC("cgroup_skb/egress", BPF_PROG_TYPE_CGROUP_SKB, > @@ -5119,32 +5122,39 @@ int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, > return -ESRCH; > } > > -#define BTF_PREFIX "btf_trace_" > +static inline int __btf__typdef_with_prefix(struct btf *btf, const char *name, typo: typdef -> typedef But actually let's generalize it to pass BTF_KIND as another param, I think I have a need for this (we might want to do that for structs, not just typedef->func_proto). Following btf__find_by_name_kind() naming, it probably should be called btf__find_by_prefix_kind()? > + const char *prefix) > +{ > + > + size_t prefix_len = strlen(prefix); > + char btf_type_name[128]; > + > + strcpy(btf_type_name, prefix); > + strncat(btf_type_name, name, sizeof(btf_type_name) - (prefix_len + 1)); at this point snprintf(btf_type_name, "%s%.*%s", prefix, sizeof(btf_type_name) - prefix_len - 1, name) looks like a better and cleaner alternative. > + return btf__find_by_name_kind(btf, btf_type_name, BTF_KIND_TYPEDEF); > +} > + > +#define BTF_TRACE_PREFIX "btf_trace_" > +#define BTF_LSM_PREFIX "lsm_btf_" > + [...]