From mboxrd@z Thu Jan 1 00:00:00 1970 From: PJ Waskiewicz Subject: [PATCH 1/2] IPROUTE2: RTNETLINK nested attributes Date: Tue, 14 Aug 2007 11:21:19 -0700 Message-ID: <20070814182119.3800.6371.stgit@localhost.localdomain> References: <20070814182111.3800.38619.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, kaber@trash.net To: shemminger@linux-foundation.org Return-path: Received: from mga02.intel.com ([134.134.136.20]:5847 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764240AbXHNSVV (ORCPT ); Tue, 14 Aug 2007 14:21:21 -0400 In-Reply-To: <20070814182111.3800.38619.stgit@localhost.localdomain> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Patrick McHardy This adds capability for iproute2 to send nested attributes to the kernel, while maintaining backwards compatibility. Signed-off-by: Patrick McHardy --- include/libnetlink.h | 9 +++++++++ lib/libnetlink.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+), 0 deletions(-) diff --git a/include/libnetlink.h b/include/libnetlink.h index 49e248e..b67c5a5 100644 --- a/include/libnetlink.h +++ b/include/libnetlink.h @@ -39,15 +39,24 @@ extern int rtnl_send(struct rtnl_handle *rth, const char *buf, int); extern int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data); extern int addattr_l(struct nlmsghdr *n, int maxlen, int type, const void *data, int alen); extern int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len); +extern struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type); +extern int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest); +extern struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type, const void *data, int len); +extern int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *nest); extern int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data); extern int rta_addattr_l(struct rtattr *rta, int maxlen, int type, const void *data, int alen); extern int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len); extern int parse_rtattr_byindex(struct rtattr *tb[], int max, struct rtattr *rta, int len); +extern int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, struct rtattr *rta, int len); #define parse_rtattr_nested(tb, max, rta) \ (parse_rtattr((tb), (max), RTA_DATA(rta), RTA_PAYLOAD(rta))) +#define parse_rtattr_nested_compat(tb, max, rta, data, len) \ +({ data = RTA_PAYLOAD(rta) >= len ? RTA_DATA(rta) : NULL; \ + __parse_rtattr_nested_compat(tb, max, rta, len); }) + extern int rtnl_listen(struct rtnl_handle *, rtnl_filter_t handler, void *jarg); extern int rtnl_from_file(FILE *, rtnl_filter_t handler, diff --git a/lib/libnetlink.c b/lib/libnetlink.c index 555dd5c..12883fe 100644 --- a/lib/libnetlink.c +++ b/lib/libnetlink.c @@ -527,6 +527,39 @@ int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len) return 0; } +struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type) +{ + struct rtattr *nest = NLMSG_TAIL(n); + + addattr_l(n, maxlen, type, NULL, 0); + return nest; +} + +int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest) +{ + nest->rta_len = (void *)NLMSG_TAIL(n) - (void *)nest; + return n->nlmsg_len; +} + +struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type, + const void *data, int len) +{ + struct rtattr *start = NLMSG_TAIL(n); + + addattr_l(n, maxlen, type, data, len); + addattr_nest(n, maxlen, type); + return start; +} + +int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *start) +{ + struct rtattr *nest = (void *)start + NLMSG_ALIGN(start->rta_len); + + start->rta_len = (void *)NLMSG_TAIL(n) - (void *)start; + addattr_nest_end(n, nest); + return n->nlmsg_len; +} + int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data) { int len = RTA_LENGTH(4); @@ -589,3 +622,16 @@ int parse_rtattr_byindex(struct rtattr *tb[], int max, struct rtattr *rta, int l fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len); return i; } + +int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, struct rtattr *rta, + int len) +{ + if (RTA_PAYLOAD(rta) < len) + return -1; + if (RTA_PAYLOAD(rta) >= RTA_ALIGN(len) + sizeof(struct rtattr)) { + rta = RTA_DATA(rta) + RTA_ALIGN(len); + return parse_rtattr_nested(tb, max, rta); + } + memset(tb, 0, sizeof(struct rtattr *) * max); + return 0; +}