From patchwork Tue Mar 22 19:46:24 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Carlos_Falgueras_Garc=C3=ADa?= X-Patchwork-Id: 600927 X-Patchwork-Delegate: pablo@netfilter.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3qV39Z4PjPz9s5M for ; Wed, 23 Mar 2016 06:46:42 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=riseup.net header.i=@riseup.net header.b=RC3p2jaX; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751686AbcCVTql (ORCPT ); Tue, 22 Mar 2016 15:46:41 -0400 Received: from mx1.riseup.net ([198.252.153.129]:51427 "EHLO mx1.riseup.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750910AbcCVTql (ORCPT ); Tue, 22 Mar 2016 15:46:41 -0400 Received: from cotinga.riseup.net (unknown [10.0.1.164]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (Client CN "*.riseup.net", Issuer "COMODO RSA Domain Validation Secure Server CA" (verified OK)) by mx1.riseup.net (Postfix) with ESMTPS id 263221AD2FB; Tue, 22 Mar 2016 19:46:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=riseup.net; s=squak; t=1458676000; bh=kkXceUFgud7tqfJgZqSImt6vw5qLK8PQAARj8MDfiOg=; h=From:To:Cc:Subject:Date:From; b=RC3p2jaX1Lp2ofjyUn9BFFQdVq24USuqJkeRhep9A5Er/RRnC884m+aEAU63d35eN tyhFghwXHU7yLtna6sepKJpgQGOjv0oQkooUJtA/sZCV+qHogPCZRw5CCd6m9pJiew bt/o87phfeglMW6Pyapus5a8O2EOx2xQHjxingWQ= Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: carlosfg) with ESMTPSA id 7E1734002B From: =?UTF-8?q?Carlos=20Falgueras=20Garc=C3=ADa?= To: netfilter-devel@vger.kernel.org Cc: pablo@netfilter.org, kaber@trash.net Subject: [PATCH 1/4 v6] libnftnl: Implement new buffer of TLV objects Date: Tue, 22 Mar 2016 20:46:24 +0100 Message-Id: <1458675987-32398-1-git-send-email-carlosfg@riseup.net> MIME-Version: 1.0 X-Virus-Scanned: clamav-milter 0.99 at mx1.riseup.net X-Virus-Status: Clean Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org These functions allow to create a buffer (nftnl_udata_buf) of TLV objects (nftnl_udata). It is inspired by libmnl/src/attr.c. It can be used to store several variable length user data into an object. Example usage: ``` struct nftnl_udata_buf *buf; struct nftnl_udata *attr; const char str[] = "Hello World!"; buf = nftnl_udata_buf_alloc(UDATA_SIZE); if (!buf) { perror("OOM"); exit(EXIT_FAILURE); } if (!nftnl_udata_put_strz(buf, MY_TYPE, str)) { perror("Can't put attribute \"%s\"", str); exit(EXIT_FAILURE); } nftnl_udata_for_each(buf, attr) { printf("%s\n", (char *)nftnl_udata_attr_value(attr)); } nftnl_udata_buf_free(buf); ``` Signed-off-by: Carlos Falgueras García --- include/Makefile.am | 1 + include/libnftnl/Makefile.am | 1 + include/libnftnl/udata.h | 54 ++++++++++++++++++ include/udata.h | 40 +++++++++++++ src/Makefile.am | 1 + src/libnftnl.map | 16 ++++++ src/udata.c | 131 +++++++++++++++++++++++++++++++++++++++++++ 7 files changed, 244 insertions(+) create mode 100644 include/libnftnl/udata.h create mode 100644 include/udata.h create mode 100644 src/udata.c diff --git a/include/Makefile.am b/include/Makefile.am index be9eb9b..9f55737 100644 --- a/include/Makefile.am +++ b/include/Makefile.am @@ -12,4 +12,5 @@ noinst_HEADERS = internal.h \ expr.h \ json.h \ set_elem.h \ + udata.h \ utils.h diff --git a/include/libnftnl/Makefile.am b/include/libnftnl/Makefile.am index 84f01b6..457ec95 100644 --- a/include/libnftnl/Makefile.am +++ b/include/libnftnl/Makefile.am @@ -7,4 +7,5 @@ pkginclude_HEADERS = batch.h \ set.h \ ruleset.h \ common.h \ + udata.h \ gen.h diff --git a/include/libnftnl/udata.h b/include/libnftnl/udata.h new file mode 100644 index 0000000..166bb06 --- /dev/null +++ b/include/libnftnl/udata.h @@ -0,0 +1,54 @@ +#ifndef _LIBNFTNL_UDATA_H_ +#define _LIBNFTNL_UDATA_H_ + +#include +#include +#include + +/* + * nftnl user data attributes API + */ +struct nftnl_udata; +struct nftnl_udata_buf; + +/* nftnl_udata_buf */ +struct nftnl_udata_buf *nftnl_udata_buf_alloc(uint32_t data_size); +void nftnl_udata_buf_free(struct nftnl_udata_buf *buf); +uint32_t nftnl_udata_buf_len(const struct nftnl_udata_buf *buf); +uint32_t nftnl_udata_buf_size(const struct nftnl_udata_buf *buf); +void *nftnl_udata_buf_data(const struct nftnl_udata_buf *buf); +void nftnl_udata_buf_put(struct nftnl_udata_buf *buf, const void *data, + uint32_t len); +struct nftnl_udata *nftnl_udata_start(const struct nftnl_udata_buf *buf); +struct nftnl_udata *nftnl_udata_end(const struct nftnl_udata_buf *buf); + +/* putters */ +bool nftnl_udata_put(struct nftnl_udata_buf *buf, uint8_t type, uint32_t len, + const void *value); +bool nftnl_udata_put_strz(struct nftnl_udata_buf *buf, uint8_t type, + const char *strz); + +/* nftnl_udata_attr */ +uint8_t nftnl_udata_attr_type(const struct nftnl_udata *attr); +uint8_t nftnl_udata_attr_len(const struct nftnl_udata *attr); +void *nftnl_udata_attr_value(const struct nftnl_udata *attr); + +/* iterator */ +struct nftnl_udata *nftnl_udata_attr_next(const struct nftnl_udata *attr); + +#define nftnl_udata_for_each(buf, attr) \ + for ((attr) = nftnl_udata_start(buf); \ + (char *)(nftnl_udata_end(buf)) > (char *)(attr); \ + (attr) = nftnl_udata_attr_next(attr)) + +#define nftnl_udata_for_each_data(data, data_len, attr) \ + for ((attr) = (struct nftnl_udata *)(data); \ + (char *)(data + data_len) > (char *)(attr); \ + (attr) = nftnl_udata_attr_next(attr)) + +typedef int (*nftnl_udata_cb_t)(const struct nftnl_udata *attr, + void *data); +int nftnl_udata_parse(const void *data, uint32_t data_len, nftnl_udata_cb_t cb, + void *cb_data); + +#endif /* _LIBNFTNL_UDATA_H_ */ diff --git a/include/udata.h b/include/udata.h new file mode 100644 index 0000000..407a3b9 --- /dev/null +++ b/include/udata.h @@ -0,0 +1,40 @@ +#ifndef _LIBNFTNL_UDATA_INTERNAL_H_ +#define _LIBNFTNL_UDATA_INTERNAL_H_ + +#include +#include + +/* + * TLV structures: + * nftnl_udata + * <-------- HEADER --------> <------ PAYLOAD ------> + * +------------+-------------+- - - - - - - - - - - -+ + * | type | len | value | + * | (1 byte) | (1 byte) | | + * +--------------------------+- - - - - - - - - - - -+ + * <-- sizeof(nftnl_udata) -> <-- nftnl_udata->len --> + */ +struct nftnl_udata { + uint8_t type; + uint8_t len; + unsigned char value[]; +} __attribute__((__packed__)); + +/* + * +---------------------------------++ + * | data[] || + * | || || + * | \/ \/ + * +-------+-------+-------+-------+ ... +-------+- - - - - - -+ + * | size | end | TLV | TLV | | TLV | Empty | + * +-------+-------+-------+-------+ ... +-------+- - - - - - -+ + * |<---- nftnl_udata_len() ---->| + * |<----------- nftnl_udata_size() ---------->| + */ +struct nftnl_udata_buf { + uint32_t size; + char *end; + char data[]; +}; + +#endif /* _LIBNFTNL_UDATA_INTERNAL_H_ */ diff --git a/src/Makefile.am b/src/Makefile.am index a27e292..7e580e4 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -19,6 +19,7 @@ libnftnl_la_SOURCES = utils.c \ ruleset.c \ mxml.c \ jansson.c \ + udata.c \ expr.c \ expr_ops.c \ expr/bitwise.c \ diff --git a/src/libnftnl.map b/src/libnftnl.map index 2e193b7..b2e2326 100644 --- a/src/libnftnl.map +++ b/src/libnftnl.map @@ -512,4 +512,20 @@ LIBNFTNL_4.1 { nftnl_trace_get_data; nftnl_trace_nlmsg_parse; + + nftnl_udata_buf_alloc; + nftnl_udata_buf_free; + nftnl_udata_buf_len; + nftnl_udata_buf_size; + nftnl_udata_buf_data; + nftnl_udata_buf_put; + nftnl_udata_start; + nftnl_udata_end; + nftnl_udata_put; + nftnl_udata_put_strz; + nftnl_udata_attr_type; + nftnl_udata_attr_len; + nftnl_udata_attr_value; + nftnl_udata_attr_next; + nftnl_udata_parse; } LIBNFTNL_4; diff --git a/src/udata.c b/src/udata.c new file mode 100644 index 0000000..afe9057 --- /dev/null +++ b/src/udata.c @@ -0,0 +1,131 @@ +#include +#include +#include + +#include +#include +#include + +struct nftnl_udata_buf *nftnl_udata_buf_alloc(uint32_t data_size) +{ + struct nftnl_udata_buf *buf; + + buf = malloc(sizeof(struct nftnl_udata_buf) + data_size); + if (!buf) + return NULL; + buf->size = data_size; + buf->end = buf->data; + + return buf; +} +EXPORT_SYMBOL(nftnl_udata_buf_alloc); + +void nftnl_udata_buf_free(struct nftnl_udata_buf *buf) +{ + free(buf); +} +EXPORT_SYMBOL(nftnl_udata_buf_free); + +uint32_t nftnl_udata_buf_len(const struct nftnl_udata_buf *buf) +{ + return (uint32_t)(buf->end - buf->data); +} +EXPORT_SYMBOL(nftnl_udata_buf_len); + +uint32_t nftnl_udata_buf_size(const struct nftnl_udata_buf *buf) +{ + return buf->size; +} +EXPORT_SYMBOL(nftnl_udata_buf_size); + +void *nftnl_udata_buf_data(const struct nftnl_udata_buf *buf) +{ + return (void *)buf->data; +} +EXPORT_SYMBOL(nftnl_udata_buf_data); + +void nftnl_udata_buf_put(struct nftnl_udata_buf *buf, const void *data, + uint32_t len) +{ + memcpy(buf->data, data, len <= buf->size ? len : buf->size); + buf->end = buf->data + len; +} +EXPORT_SYMBOL(nftnl_udata_buf_put); + +struct nftnl_udata *nftnl_udata_start(const struct nftnl_udata_buf *buf) +{ + return (struct nftnl_udata *)buf->data; +} +EXPORT_SYMBOL(nftnl_udata_start); + +struct nftnl_udata *nftnl_udata_end(const struct nftnl_udata_buf *buf) +{ + return (struct nftnl_udata *)buf->end; +} +EXPORT_SYMBOL(nftnl_udata_end); + +bool nftnl_udata_put(struct nftnl_udata_buf *buf, uint8_t type, uint32_t len, + const void *value) +{ + struct nftnl_udata *attr; + + if (buf->size < len + sizeof(struct nftnl_udata)) + return false; + + attr = (struct nftnl_udata *)buf->end; + attr->len = len; + attr->type = type; + memcpy(attr->value, value, len); + + buf->end = (char *)nftnl_udata_attr_next(attr); + + return true; +} +EXPORT_SYMBOL(nftnl_udata_put); + +bool nftnl_udata_put_strz(struct nftnl_udata_buf *buf, uint8_t type, + const char *strz) +{ + return nftnl_udata_put(buf, type, strlen(strz) + 1, strz); +} +EXPORT_SYMBOL(nftnl_udata_put_strz); + +uint8_t nftnl_udata_attr_type(const struct nftnl_udata *attr) +{ + return attr->type; +} +EXPORT_SYMBOL(nftnl_udata_attr_type); + +uint8_t nftnl_udata_attr_len(const struct nftnl_udata *attr) +{ + return attr->len; +} +EXPORT_SYMBOL(nftnl_udata_attr_len); + +void *nftnl_udata_attr_value(const struct nftnl_udata *attr) +{ + return (void *)attr->value; +} +EXPORT_SYMBOL(nftnl_udata_attr_value); + +struct nftnl_udata *nftnl_udata_attr_next(const struct nftnl_udata *attr) +{ + return (struct nftnl_udata *)&attr->value[attr->len]; +} +EXPORT_SYMBOL(nftnl_udata_attr_next); + +int nftnl_udata_parse(const void *data, uint32_t data_len, nftnl_udata_cb_t cb, + void *cb_data) +{ + int ret = 0; + const struct nftnl_udata *attr; + + nftnl_udata_for_each_data(data, data_len, attr) { + ret = cb(attr, cb_data); + if (ret <= 0) + return ret; + } + + return ret; +} +EXPORT_SYMBOL(nftnl_udata_parse);