From: Pavel Emelyanov <xemul@parallels•com>
To: Stephen Hemminger <shemminger@linux-foundation•org>,
Linux Netdev List <netdev@vger•kernel.org>
Subject: [PATCH 1/2] iproute: Add magic cookie to route dump file
Date: Fri, 27 Jul 2012 08:55:41 +0400 [thread overview]
Message-ID: <50121F4D.8090606@parallels.com> (raw)
In order to somehow verify that a blob contains route dump a
4-bytes magic is put at the head of the data and is checked
on restore.
Magic digits are taken from Portland (OR) coordinates :) Is
there any more reliable way of generating such?
Signed-of-by: Pavel Emelyanov <xemul@parallels•com>
---
ip/iproute.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++-------
1 files changed, 47 insertions(+), 7 deletions(-)
diff --git a/ip/iproute.c b/ip/iproute.c
index 5cd313e..bbb3923 100644
--- a/ip/iproute.c
+++ b/ip/iproute.c
@@ -1064,6 +1064,8 @@ static int iproute_flush_cache(void)
return 0;
}
+static __u32 route_dump_magic = 0x45311224;
+
int save_route(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
{
int ret;
@@ -1072,11 +1074,6 @@ int save_route(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
struct rtattr *tb[RTA_MAX+1];
int host_len = -1;
- if (isatty(STDOUT_FILENO)) {
- fprintf(stderr, "Not sending binary stream to stdout\n");
- return -1;
- }
-
host_len = calc_host_len(r);
len -= NLMSG_LENGTH(sizeof(*r));
parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);
@@ -1093,6 +1090,24 @@ int save_route(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
return ret == n->nlmsg_len ? 0 : ret;
}
+static int save_route_prep(void)
+{
+ int ret;
+
+ if (isatty(STDOUT_FILENO)) {
+ fprintf(stderr, "Not sending binary stream to stdout\n");
+ return -1;
+ }
+
+ ret = write(STDOUT_FILENO, &route_dump_magic, sizeof(route_dump_magic));
+ if (ret != sizeof(route_dump_magic)) {
+ fprintf(stderr, "Can't write magic to dump file\n");
+ return -1;
+ }
+
+ return 0;
+}
+
static int iproute_list_flush_or_save(int argc, char **argv, int action)
{
int do_ipv6 = preferred_family;
@@ -1101,9 +1116,12 @@ static int iproute_list_flush_or_save(int argc, char **argv, int action)
unsigned int mark = 0;
rtnl_filter_t filter_fn;
- if (action == IPROUTE_SAVE)
+ if (action == IPROUTE_SAVE) {
+ if (save_route_prep())
+ return -1;
+
filter_fn = save_route;
- else
+ } else
filter_fn = print_route;
iproute_reset_filter();
@@ -1521,8 +1539,30 @@ int restore_handler(const struct sockaddr_nl *nl, struct nlmsghdr *n, void *arg)
return ret;
}
+static int route_dump_check_magic(void)
+{
+ int ret;
+ __u32 magic = 0;
+
+ if (isatty(STDIN_FILENO)) {
+ fprintf(stderr, "Can't restore route dump from a terminal\n");
+ return -1;
+ }
+
+ ret = fread(&magic, sizeof(magic), 1, stdin);
+ if (magic != route_dump_magic) {
+ fprintf(stderr, "Magic mismatch (%d elems, %x magic)\n", ret, magic);
+ return -1;
+ }
+
+ return 0;
+}
+
int iproute_restore(void)
{
+ if (route_dump_check_magic())
+ exit(-1);
+
exit(rtnl_from_file(stdin, &restore_handler, NULL));
}
--
1.5.5.6
next reply other threads:[~2012-07-27 4:55 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-27 4:55 Pavel Emelyanov [this message]
2012-07-27 4:57 ` [PATCH 2/2] iproute: Add route showdump command (v2) Pavel Emelyanov
2012-07-27 5:03 ` Pavel Emelyanov
2012-07-27 6:06 ` Pavel Emelyanov
2012-07-27 17:05 ` Stephen Hemminger
2012-09-11 15:47 ` [PATCH] iproute: Add ability to save, restore and show the interfaces' addresses (resend) Pavel Emelyanov
2012-09-11 16:18 ` Stephen Hemminger
2012-09-07 16:14 ` [PATCH 2/2] iproute: Add route showdump command (v2) Stephen Hemminger
2012-07-27 10:46 ` [PATCH 1/2] iproute: Add magic cookie to route dump file David Laight
2012-07-27 13:35 ` Pavel Emelyanov
2012-07-27 16:59 ` Stephen Hemminger
2012-08-17 20:49 ` Stephen Hemminger
2012-08-20 8:05 ` Pavel Emelyanov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=50121F4D.8090606@parallels.com \
--to=xemul@parallels$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
--cc=shemminger@linux-foundation$(echo .)org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox