Commit Graph

13 Commits

Author SHA1 Message Date
Peter Krempa
b17c0f0e9a leaseshelper: Fix incorrect alignment of a switch case
Introduced in ca6dbdd047
2014-12-03 18:47:24 +01:00
Peter Krempa
3be8c1f002 leaseshelper: Skip entries missing expiry time on INIT action
Coverity pointed out that in other places we always check the return
value from virJSONValueObjectGetNumberLong() but not in the new addition
in leaseshelper. To solve the issue and also be more robust in case
somebody would corrupt the file, skip outputting of the lease entry in
case the expiry time is missing.
2014-12-03 18:47:09 +01:00
Peter Krempa
ca6dbdd047 leaseshelper: Refactor control flow
Untangle a few conditions into a case statement and improve reporting of
invaid commands.
2014-12-03 14:22:40 +01:00
Nehal J Wani
0f87054b61 leaseshelper: improvements to support all events
This patch enables the helper program to detect event(s) triggered when
there is a change in lease length or expiry and client-id. This
transfers complete control of leases database to libvirt and obsoletes
use of the lease database file (<network-name>.leases). That file will
not be created, read, or written.  This is achieved by adding the option
--leasefile-ro to dnsmasq and passing a custom env var to leaseshelper,
which helps us map events related to leases with their corresponding
network bridges, no matter what the event be.

Also, this requires the addition of a new non-lease entry in our custom
lease database: "server-duid". It is required to identify a DHCPv6
server.

Now that dnsmasq doesn't maintain its own leases database, it relies on
our helper program to tell it about previous leases and server duid.
Thus, this patch makes our leases program honor an extra action: "init",
in which it sends the known info in a particular format to dnsmasq
by printing it to stdout.

The drawback of this change is that upgrade to this new approach does
not transfer the existing leases for the network if the leaseshelper
wasn't already used.
2014-12-03 14:22:40 +01:00
John Ferlan
d3f0708e84 network: Resolve Coverity FORWARD_NULL
If the VIR_STRDUP(exptime,...) fails, then we will jump to cleanup,
no need to check if exptime is set which causes Coverity to issue
a complaint in the virStrToLong_ll call because there wasn't a check
for a NULL value while there was one for the reference right after
the VIR_STRDUP().

Signed-off-by: John Ferlan <jferlan@redhat.com>
2014-09-11 08:10:13 -04:00
Nehal J Wani
6675a0ab65 leaseshelper: avoid mem leak after storing lease entries
Contents of existing lease file were being stored in a variable
which was never freed.
2014-07-23 19:27:39 -06:00
Peter Krempa
0657ed2a5c net: leaseshelper: Refactor copying of old entries to avoid double free
When copying entries from the old lease file into the new array the old
code would copy the pointer of the json object into the second array
without removing it from the first. Afterwards when both arrays were
freed this might lead to a crash due to access of already freed memory.

Refactor the code to use the new array item stealing helper added to the
json code so that the entry resides just in one array.
2014-06-17 09:10:08 +02:00
Peter Krempa
45d51681ce net: leaseshelper: Ignore corrupted lease file and rewrite it
Instead of reporting an error and terminating, rewrite the file with
the newly learned info.
2014-06-17 09:02:26 +02:00
Peter Krempa
f1385e222e net: leaseshelper: Don't crash if DNSMASQ doesn't provide lease expiry
The value is provided via environment and causes a crash if not defined.
2014-06-17 08:55:50 +02:00
Pavel Hrdina
647bdf02d8 leaseshelper: fix another crash
We create a 'lease_new' when we are adding new lease entry, then later
in the code we add the 'lease_new' into a 'leases_array_new' which
leads into the crash because we double free the 'lease_new'.

To prevent the double free we set the 'lease_new' to NULL after
successful append into the 'leases_array_new'.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2014-06-16 14:41:19 +02:00
Pavel Hrdina
a93504cca4 leaseshelper: fix crash
Commit baafe668 introduced new leaseshelper with a crash of freeing
env string. Calling 'getenv()' inside 'virGetEnvAllowSUID()' may
return a static string and we definitely should not free it.

The author probably want to free the copy of that string.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2014-06-11 17:21:11 +02:00
Pavel Hrdina
f8a0c9edf0 Fix build on freebsd
On freebsd there isn't known "setlocale" so we have to include locale.h
2014-06-02 16:45:42 +02:00
Nehal J Wani
baafe668fa Add helper program to create custom leases
Introduce helper program to catch events from dnsmasq and maintain a custom
lease file per network. It supports dhcpv4 and dhcpv6. The file is saved as
"<interface-name>.status".

Each lease contains the following info:
<expiry-time (epoch time)> <mac> <iaid> <ip-address> <hostname> <clientid>

Example of custom leases file content:
[
    {
        "iaid": "1221229",
        "ip-address": "2001:db8:ca2:2:1::95",
        "mac-address": "52:54:00:12:a2:6d",
        "hostname": "Fedora20",
        "client-id": "00:04:1a:c1:d9:6b:5a:0a:e2:bc:f8:4b:1e:37:2e:38:22:55",
        "expiry-time": 1393244216
    },
    {
        "ip-address": "192.168.150.208",
        "mac-address": "52:54:00:11:56:b3",
        "hostname": "Wani-PC",
        "client-id": "01:52:54:00:11:56:b3",
        "expiry-time": 1393244248
    }
]

src/Makefile.am:
   * Add options to compile the helper program

src/network/bridge_driver.c:
   * Introduce networkDnsmasqLeaseFileNameCustom()
   * Invoke helper program along with dnsmasq
   * Delete the .status file when corresponding n/w is destroyed.

src/network/leaseshelper.c
   * Helper program to create the custom lease file
2014-06-02 11:45:10 +01:00