From patchwork Mon May 17 22:53:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitrii Banshchikov X-Patchwork-Id: 12263315 X-Patchwork-Delegate: bpf@iogearbox.net 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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 00EFAC433ED for ; Mon, 17 May 2021 22:54:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D82CC61209 for ; Mon, 17 May 2021 22:54:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344265AbhEQWz2 (ORCPT ); Mon, 17 May 2021 18:55:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41794 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344275AbhEQWzO (ORCPT ); Mon, 17 May 2021 18:55:14 -0400 Received: from mail-wr1-x436.google.com (mail-wr1-x436.google.com [IPv6:2a00:1450:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46785C061761 for ; Mon, 17 May 2021 15:53:57 -0700 (PDT) Received: by mail-wr1-x436.google.com with SMTP id i17so8026892wrq.11 for ; Mon, 17 May 2021 15:53:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ubique-spb-ru.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=jVs5W8Q7mp+DFqI9hJt1Fi1/9BKgvTs4LikxRXRXvus=; b=YU2HVVdebqEuzumZPGGfdAuMbgnud6qEn8MQhVoGAclEjW/5OpuZvRfsEtXsx7YRA/ lmAr3j43CQe/3e3g0y2K9LbfQgaPDHnMuDy2WbChP0zisMSdMvjxTGkAH+NmCdA2fe89 wrRgj4Cj589aiwKJy+2tYpAVhMJRH5RSXYHlsGDmc+y64RpEdKeZo8ya/8791lIqFPub Xc+3JMjthhPW/U7nK0edgoDQ6J/tAA7T+zkUyOoJwUGpg19lr6Ixhxai/Xmlqpp8NfJx 2n3Ylw1vI0dliGoRYE9sDa3x7fID4q9s48oSiBgxNsZX9H7kXlI40kpproqP5d/FzUXo lynw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=jVs5W8Q7mp+DFqI9hJt1Fi1/9BKgvTs4LikxRXRXvus=; b=I99mc7ZBWncGj+kEeEZQh3qZEtAIN4Cyzim868hoJl0lL7bvfj9E4VkFyZx0cPIe3c AHZLLj3/Kbw0Wj9JWsC5RI+i978Eyb3UL6yEQx9SyiDsoiZsWMrTF8I1uWnPFCF5vfmd psfGkAE5jnS1G56d7UDs2vSrKiOhXB0bLeikwMbcmk+gTb8chqaAqjtNRkvpSyEok8RT Hqr2O3kALr5DuNRcXkF/ToLIDBdUFezdQtD07n1p/nFgsymVwGsReP7dx2vTV7Pzd488 ijQ90aj6TuPjDFm4OssOkc3SRhifBX1YY8TLpqck3RV4fJz5sHHLASyjbIxuOkzqbk+y gkmA== X-Gm-Message-State: AOAM533n4q5kBoRa9ZaTfFyoaOWknmop4Q1L1vOPmlpr+8vaJ8DF0XOf frmKX7r8ntE+ATJTeg4As91LtAAaVb/2+OpWKWA= X-Google-Smtp-Source: ABdhPJxC19PmYktYwqjTZbmfasMsCCINXdBH8ITNp2Xi6MBt5E/GKsHd5n8zxOJy4mDJwzWs4FMHXA== X-Received: by 2002:a5d:4dcc:: with SMTP id f12mr1394928wru.224.1621292035773; Mon, 17 May 2021 15:53:55 -0700 (PDT) Received: from localhost ([154.21.15.43]) by smtp.gmail.com with ESMTPSA id t11sm19121827wrz.57.2021.05.17.15.53.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 May 2021 15:53:55 -0700 (PDT) From: Dmitrii Banshchikov To: bpf@vger.kernel.org Cc: Dmitrii Banshchikov , ast@kernel.org, davem@davemloft.net, daniel@iogearbox.net, andrii@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, netdev@vger.kernel.org, rdna@fb.com Subject: [PATCH bpf-next 10/11] bpfilter: Add handling of setsockopt() calls Date: Tue, 18 May 2021 02:53:07 +0400 Message-Id: <20210517225308.720677-11-me@ubique.spb.ru> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210517225308.720677-1-me@ubique.spb.ru> References: <20210517225308.720677-1-me@ubique.spb.ru> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add support of iptables' setsockopt(2). The parameters of a setsockopt(2) call are passed by struct mbox_request which contains a type of the setsockopt(2) call and its memory buffer description. The typical way to handle hooked setsockopt(2) call is to read the supplied memory buffer via pvm_read(), process it and write an answer to the process memory via pvm_write(). Signed-off-by: Dmitrii Banshchikov --- net/bpfilter/Makefile | 3 +- net/bpfilter/sockopt.c | 357 +++++++++++++++++++++++++++++++++++++++++ net/bpfilter/sockopt.h | 14 ++ 3 files changed, 373 insertions(+), 1 deletion(-) create mode 100644 net/bpfilter/sockopt.c create mode 100644 net/bpfilter/sockopt.h diff --git a/net/bpfilter/Makefile b/net/bpfilter/Makefile index e0090563f2ca..bae14fc9e396 100644 --- a/net/bpfilter/Makefile +++ b/net/bpfilter/Makefile @@ -4,7 +4,8 @@ # userprogs := bpfilter_umh -bpfilter_umh-objs := main.o bflog.o io.o map-common.o context.o match.o target.o rule.o table.o +bpfilter_umh-objs := main.o bflog.o io.o map-common.o context.o match.o target.o rule.o table.o \ + sockopt.o userccflags += -I $(srctree)/tools/include/ -I $(srctree)/tools/include/uapi ifeq ($(CONFIG_BPFILTER_UMH), y) diff --git a/net/bpfilter/sockopt.c b/net/bpfilter/sockopt.c new file mode 100644 index 000000000000..16f0ade203c0 --- /dev/null +++ b/net/bpfilter/sockopt.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2021 Telegram FZ-LLC + */ + +#define _GNU_SOURCE + +#include "sockopt.h" + +#include +#include + +#include +#include +#include + +#include "bflog.h" +#include "context.h" +#include "io.h" +#include "msgfmt.h" +#include "table-map.h" + +static int read_ipt_get_info(const struct mbox_request *req, struct bpfilter_ipt_get_info *info) +{ + int err; + + if (req->len != sizeof(*info)) + return -EINVAL; + + err = pvm_read(req->pid, info, (const void *)req->addr, sizeof(*info)); + if (err) + return err; + + info->name[sizeof(info->name) - 1] = '\0'; + + return 0; +} + +static int sockopt_get_info(struct context *ctx, const struct mbox_request *req) +{ + struct bpfilter_ipt_get_info info; + struct table *table; + int err; + + BFLOG_DEBUG(ctx, "handling IPT_SO_GET_INFO\n"); + + if (req->len != sizeof(info)) + return -EINVAL; + + err = read_ipt_get_info(req, &info); + if (err) { + BFLOG_DEBUG(ctx, "cannot read ipt_get_info: %s\n", strerror(-err)); + return err; + } + + table = table_map_find(&ctx->table_map, info.name); + if (IS_ERR(table)) { + BFLOG_DEBUG(ctx, "cannot find table: '%s'\n", info.name); + return -ENOENT; + } + + table_get_info(table, &info); + + return pvm_write(req->pid, (void *)req->addr, &info, sizeof(info)); +} + +static int read_ipt_get_entries(const struct mbox_request *req, + struct bpfilter_ipt_get_entries *entries) +{ + int err; + + if (req->len < sizeof(*entries)) + return -EINVAL; + + err = pvm_read(req->pid, entries, (const void *)req->addr, sizeof(*entries)); + if (err) + return err; + + entries->name[sizeof(entries->name) - 1] = '\0'; + + return 0; +} + +static int sockopt_get_entries(struct context *ctx, const struct mbox_request *req) +{ + struct bpfilter_ipt_get_entries get_entries, *entries; + struct table *table; + int err; + + BFLOG_DEBUG(ctx, "handling IPT_SO_GET_ENTRIES\n"); + + err = read_ipt_get_entries(req, &get_entries); + if (err) { + BFLOG_DEBUG(ctx, "cannot read ipt_get_entries: %s\n", strerror(-err)); + return err; + } + + table = table_map_find(&ctx->table_map, get_entries.name); + if (IS_ERR(table)) { + BFLOG_DEBUG(ctx, "cannot find table: '%s'\n", get_entries.name); + return -ENOENT; + } + + if (get_entries.size != table->size) { + BFLOG_DEBUG(ctx, "table '%s' get entries size mismatch\n", get_entries.name); + return -EINVAL; + } + + entries = (struct bpfilter_ipt_get_entries *)req->addr; + + err = pvm_write(req->pid, entries->name, table->name, sizeof(entries->name)); + if (err) + return err; + + err = pvm_write(req->pid, &entries->size, &table->size, sizeof(table->size)); + if (err) + return err; + + return pvm_write(req->pid, entries->entries, table->entries, table->size); +} + +static int read_ipt_get_revision(const struct mbox_request *req, + struct bpfilter_ipt_get_revision *revision) +{ + int err; + + if (req->len != sizeof(*revision)) + return -EINVAL; + + err = pvm_read(req->pid, revision, (const void *)req->addr, sizeof(*revision)); + if (err) + return err; + + revision->name[sizeof(revision->name) - 1] = '\0'; + + return 0; +} + +static int sockopt_get_revision_match(struct context *ctx, const struct mbox_request *req) +{ + struct bpfilter_ipt_get_revision get_revision; + const struct match_ops *found; + int err; + + BFLOG_DEBUG(ctx, "handling IPT_SO_GET_REVISION_MATCH\n"); + + err = read_ipt_get_revision(req, &get_revision); + if (err) + return err; + + found = match_ops_map_find(&ctx->match_ops_map, get_revision.name); + if (IS_ERR(found)) { + BFLOG_DEBUG(ctx, "cannot find match: '%s'\n", get_revision.name); + return PTR_ERR(found); + } + + return found->revision; +} + +static struct bpfilter_ipt_replace *read_ipt_replace(const struct mbox_request *req) +{ + struct bpfilter_ipt_replace *replace; + int err; + + if (req->len < sizeof(*replace)) + return ERR_PTR(-EINVAL); + + replace = malloc(req->len); + if (!replace) + return ERR_PTR(-ENOMEM); + + err = pvm_read(req->pid, replace, (const void *)req->addr, sizeof(*replace)); + if (err) + goto err_free; + + if (replace->num_counters == 0) { + err = -EINVAL; + goto err_free; + } + + if (replace->num_counters >= INT_MAX / sizeof(struct bpfilter_ipt_counters)) { + err = -ENOMEM; + goto err_free; + } + + replace->name[sizeof(replace->name) - 1] = '\0'; + + // TODO: add more checks here + + err = pvm_read(req->pid, replace->entries, (const void *)req->addr + sizeof(*replace), + req->len - sizeof(*replace)); + if (err) + goto err_free; + + return replace; + +err_free: + free(replace); + + return ERR_PTR(err); +} + +static int sockopt_set_replace(struct context *ctx, const struct mbox_request *req) +{ + struct bpfilter_ipt_replace *ipt_replace; + struct table *table, *new_table = NULL; + int err; + + BFLOG_DEBUG(ctx, "handling IPT_SO_SET_REPLACE\n"); + + ipt_replace = read_ipt_replace(req); + if (IS_ERR(ipt_replace)) { + BFLOG_DEBUG(ctx, "cannot read ipt_replace: %s\n", strerror(-PTR_ERR(ipt_replace))); + return PTR_ERR(ipt_replace); + } + + table = table_map_find(&ctx->table_map, ipt_replace->name); + if (IS_ERR(table)) { + err = PTR_ERR(table); + BFLOG_DEBUG(ctx, "cannot find table: '%s'\n", ipt_replace->name); + goto cleanup; + } + + new_table = create_table(ctx, ipt_replace); + if (IS_ERR(new_table)) { + err = PTR_ERR(new_table); + BFLOG_DEBUG(ctx, "cannot read table: %s\n", strerror(-PTR_ERR(new_table))); + goto cleanup; + } + + // Here be codegen + // ... + // + + err = table_map_update(&ctx->table_map, new_table->name, new_table); + if (err) { + BFLOG_DEBUG(ctx, "cannot update table map: %s\n", strerror(-err)); + goto cleanup; + } + + list_add_tail(&new_table->list, &ctx->table_list); + new_table = table; + +cleanup: + if (!IS_ERR(new_table)) + free_table(new_table); + + free(ipt_replace); + + return err; +} + +static struct bpfilter_ipt_counters_info *read_ipt_counters_info(const struct mbox_request *req) +{ + struct bpfilter_ipt_counters_info *info; + size_t size; + int err; + + if (req->len < sizeof(*info)) + return ERR_PTR(-EINVAL); + + info = malloc(req->len); + if (!info) + return ERR_PTR(-ENOMEM); + + err = pvm_read(req->pid, info, (const void *)req->addr, sizeof(*info)); + if (err) + goto err_free; + + // TODO add more size checks here + + size = info->num_counters * sizeof(info->counters[0]); + if (req->len != sizeof(*info) + size) { + err = -EINVAL; + goto err_free; + } + + info->name[sizeof(info->name) - 1] = '\0'; + + err = pvm_read(req->pid, info->counters, (const void *)req->addr + sizeof(*info), size); + if (err) + goto err_free; + + return info; + +err_free: + free(info); + + return ERR_PTR(err); +} + +static int sockopt_set_add_counters(struct context *ctx, const struct mbox_request *req) +{ + struct bpfilter_ipt_counters_info *info; + struct table *table; + int err = 0; + + BFLOG_DEBUG(ctx, "handling IPT_SO_SET_ADD_COUNTERS\n"); + + info = read_ipt_counters_info(req); + if (IS_ERR(info)) { + err = PTR_ERR(info); + BFLOG_DEBUG(ctx, "cannot read ipt_counters_info: %s\n", strerror(-err)); + goto err_free; + } + + table = table_map_find(&ctx->table_map, info->name); + if (IS_ERR(table)) { + err = PTR_ERR(table); + BFLOG_DEBUG(ctx, "cannot find table: '%s'\n", info->name); + goto err_free; + } + + // TODO handle counters + +err_free: + free(info); + + return err; +} + +static int handle_get_request(struct context *ctx, const struct mbox_request *req) +{ + switch (req->cmd) { + case 0: + return 0; + case BPFILTER_IPT_SO_GET_INFO: + return sockopt_get_info(ctx, req); + case BPFILTER_IPT_SO_GET_ENTRIES: + return sockopt_get_entries(ctx, req); + case BPFILTER_IPT_SO_GET_REVISION_MATCH: + return sockopt_get_revision_match(ctx, req); + } + + BFLOG_NOTICE(ctx, "Unexpected SO_GET request: %d\n", req->cmd); + + return -ENOPROTOOPT; +} + +static int handle_set_request(struct context *ctx, const struct mbox_request *req) +{ + switch (req->cmd) { + case BPFILTER_IPT_SO_SET_REPLACE: + return sockopt_set_replace(ctx, req); + case BPFILTER_IPT_SO_SET_ADD_COUNTERS: + return sockopt_set_add_counters(ctx, req); + } + + BFLOG_NOTICE(ctx, "Unexpected SO_SET request: %d\n", req->cmd); + + return -ENOPROTOOPT; +} + +int handle_sockopt_request(struct context *ctx, const struct mbox_request *req) +{ + return req->is_set ? handle_set_request(ctx, req) : handle_get_request(ctx, req); +} diff --git a/net/bpfilter/sockopt.h b/net/bpfilter/sockopt.h new file mode 100644 index 000000000000..711c2f295d89 --- /dev/null +++ b/net/bpfilter/sockopt.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2021 Telegram FZ-LLC + */ + +#ifndef NET_BPFILTER_SOCKOPT_H +#define NET_BPFILTER_SOCKOPT_H + +struct context; +struct mbox_request; + +int handle_sockopt_request(struct context *ctx, const struct mbox_request *req); + +#endif // NET_BPFILTER_SOCKOPT_H