[xianghui,dosaboy,r=james-page,t=gema] Add IPv6 support using prefer-ipv6 flag

.bzrignore

@@ -0,0 +1,2 @@
+bin
+.coverage

config.yaml

@@ -134,3 +134,15 @@ options:
      description: |
         The IP address and netmask of the cluster (back-side) network (e.g.,
         192.168.0.0/24)
+  prefer-ipv6:
+    type: boolean
+    default: False
+    description: |
+      If True enables IPv6 support. The charm will expect network interfaces
+      to be configured with an IPv6 address. If set to False (default) IPv4
+      is expected.
+      .
+      NOTE: these charms do not currently support IPv6 privacy extension. In
+      order for this charm to function correctly, the privacy extension must be
+      disabled and a non-temporary address must be configured/available on
+      your network interface.

hooks/charmhelpers/contrib/network/ip.py

@@ -1,11 +1,16 @@
 import glob
+import re
+import subprocess
 import sys
 
 from functools import partial
 
+from charmhelpers.core.hookenv import unit_get
 from charmhelpers.fetch import apt_install
 from charmhelpers.core.hookenv import (
-    ERROR, log,
+    WARNING,
+    ERROR,
+    log
 )
 
 try:
@@ -164,13 +169,14 @@ def format_ipv6_addr(address):
     if is_ipv6(address):
         address = "[%s]" % address
     else:
-        log("Not an valid ipv6 address: %s" % address,
+        log("Not a valid ipv6 address: %s" % address, level=WARNING)
-            level=ERROR)
         address = None
+
     return address
 
 
-def get_iface_addr(iface='eth0', inet_type='AF_INET', inc_aliases=False, fatal=True, exc_list=None):
+def get_iface_addr(iface='eth0', inet_type='AF_INET', inc_aliases=False,
+                   fatal=True, exc_list=None):
     """
     Return the assigned IP address for a given interface, if any, or [].
     """
@@ -210,26 +216,105 @@ def get_iface_addr(iface='eth0', inet_type='AF_INET', inc_aliases=False, fatal=T
                 if 'addr' in entry and entry['addr'] not in exc_list:
                     addresses.append(entry['addr'])
     if fatal and not addresses:
-        raise Exception("Interface '%s' doesn't have any %s addresses." % (iface, inet_type))
+        raise Exception("Interface '%s' doesn't have any %s addresses." %
+                        (iface, inet_type))
     return addresses
 
 get_ipv4_addr = partial(get_iface_addr, inet_type='AF_INET')
 
 
-def get_ipv6_addr(iface='eth0', inc_aliases=False, fatal=True, exc_list=None):
+def get_iface_from_addr(addr):
+    """Work out on which interface the provided address is configured."""
+    for iface in netifaces.interfaces():
+        addresses = netifaces.ifaddresses(iface)
+        for inet_type in addresses:
+            for _addr in addresses[inet_type]:
+                _addr = _addr['addr']
+                # link local
+                ll_key = re.compile("(.+)%.*")
+                raw = re.match(ll_key, _addr)
+                if raw:
+                    _addr = raw.group(1)
+                if _addr == addr:
+                    log("Address '%s' is configured on iface '%s'" %
+                        (addr, iface))
+                    return iface
+
+    msg = "Unable to infer net iface on which '%s' is configured" % (addr)
+    raise Exception(msg)
+
+
+def sniff_iface(f):
+    """If no iface provided, inject net iface inferred from unit private
+    address.
     """
-    Return the assigned IPv6 address for a given interface, if any, or [].
+    def iface_sniffer(*args, **kwargs):
+        if not kwargs.get('iface', None):
+            kwargs['iface'] = get_iface_from_addr(unit_get('private-address'))
+
+        return f(*args, **kwargs)
+
+    return iface_sniffer
+
+
+@sniff_iface
+def get_ipv6_addr(iface=None, inc_aliases=False, fatal=True, exc_list=None,
+                  dynamic_only=True):
+    """Get assigned IPv6 address for a given interface.
+
+    Returns list of addresses found. If no address found, returns empty list.
+
+    If iface is None, we infer the current primary interface by doing a reverse
+    lookup on the unit private-address.
+
+    We currently only support scope global IPv6 addresses i.e. non-temporary
+    addresses. If no global IPv6 address is found, return the first one found
+    in the ipv6 address list.
     """
     addresses = get_iface_addr(iface=iface, inet_type='AF_INET6',
                                inc_aliases=inc_aliases, fatal=fatal,
                                exc_list=exc_list)
-    remotly_addressable = []
+
-    for address in addresses:
+    if addresses:
-        if not address.startswith('fe80'):
+        global_addrs = []
-            remotly_addressable.append(address)
+        for addr in addresses:
-    if fatal and not remotly_addressable:
+            key_scope_link_local = re.compile("^fe80::..(.+)%(.+)")
-        raise Exception("Interface '%s' doesn't have global ipv6 address." % iface)
+            m = re.match(key_scope_link_local, addr)
-    return remotly_addressable
+            if m:
+                eui_64_mac = m.group(1)
+                iface = m.group(2)
+            else:
+                global_addrs.append(addr)
+
+        if global_addrs:
+            # Make sure any found global addresses are not temporary
+            cmd = ['ip', 'addr', 'show', iface]
+            out = subprocess.check_output(cmd)
+            if dynamic_only:
+                key = re.compile("inet6 (.+)/[0-9]+ scope global dynamic.*")
+            else:
+                key = re.compile("inet6 (.+)/[0-9]+ scope global.*")
+
+            addrs = []
+            for line in out.split('\n'):
+                line = line.strip()
+                m = re.match(key, line)
+                if m and 'temporary' not in line:
+                    # Return the first valid address we find
+                    for addr in global_addrs:
+                        if m.group(1) == addr:
+                            if not dynamic_only or \
+                                    m.group(1).endswith(eui_64_mac):
+                                addrs.append(addr)
+
+            if addrs:
+                return addrs
+
+    if fatal:
+        raise Exception("Interface '%s' doesn't have a scope global "
+                        "non-temporary ipv6 address." % iface)
+
+    return []
 
 
 def get_bridges(vnic_dir='/sys/devices/virtual/net'):

hooks/hooks.py

@@ -40,11 +40,15 @@ from charmhelpers.fetch import (
 )
 from charmhelpers.payload.execd import execd_preinstall
 from charmhelpers.contrib.openstack.alternatives import install_alternative
-from charmhelpers.contrib.network.ip import is_ipv6
+from charmhelpers.contrib.network.ip import (
+    get_ipv6_addr,
+    format_ipv6_addr
+)
 
 from utils import (
     render_template,
     get_public_addr,
+    assert_charm_supports_ipv6
 )
 
 hooks = Hooks()
@@ -77,6 +81,14 @@ def emit_cephconf():
         'ceph_public_network': config('ceph-public-network'),
         'ceph_cluster_network': config('ceph-cluster-network'),
     }
+
+    if config('prefer-ipv6'):
+        dynamic_ipv6_address = get_ipv6_addr()[0]
+        if not config('ceph-public-network'):
+            cephcontext['public_addr'] = dynamic_ipv6_address
+        if not config('ceph-cluster-network'):
+            cephcontext['cluster_addr'] = dynamic_ipv6_address
+
     # Install ceph.conf as an alternative to support
     # co-existence with other charms that write this file
     charm_ceph_conf = "/var/lib/charm/{}/ceph.conf".format(service_name())
@@ -91,6 +103,9 @@ JOURNAL_ZAPPED = '/var/lib/ceph/journal_zapped'
 
 @hooks.hook('config-changed')
 def config_changed():
+    if config('prefer-ipv6'):
+        assert_charm_supports_ipv6()
+
     log('Monitor hosts are ' + repr(get_mon_hosts()))
 
     # Pre-flight checks
@@ -132,19 +147,14 @@ def config_changed():
 def get_mon_hosts():
     hosts = []
     addr = get_public_addr()
-    if is_ipv6(addr):
+    hosts.append('{}:6789'.format(format_ipv6_addr(addr) or addr))
-        hosts.append('[{}]:6789'.format(addr))
-    else:
-        hosts.append('{}:6789'.format(addr))
 
     for relid in relation_ids('mon'):
         for unit in related_units(relid):
             addr = relation_get('ceph-public-address', unit, relid)
             if addr is not None:
-                if is_ipv6(addr):
+                hosts.append('{}:6789'.format(
-                    hosts.append('[{}]:6789'.format(addr))
+                    format_ipv6_addr(addr) or addr))
-                else:
-                    hosts.append('{}:6789'.format(addr))
 
     hosts.sort()
     return hosts

hooks/utils.py

@@ -19,7 +19,14 @@ from charmhelpers.fetch import (
     filter_installed_packages
 )
 
+from charmhelpers.core.host import (
+    lsb_release
+)
+
 from charmhelpers.contrib.network import ip
+from charmhelpers.contrib.network.ip import (
+    get_ipv6_addr
+)
 
 TEMPLATES_DIR = 'templates'
 
@@ -64,6 +71,9 @@ def get_unit_hostname():
 
 @cached
 def get_host_ip(hostname=None):
+    if config('prefer-ipv6'):
+        return get_ipv6_addr()[0]
+
     hostname = hostname or unit_get('private-address')
     try:
         # Test to see if already an IPv4 address
@@ -81,3 +91,10 @@ def get_host_ip(hostname=None):
 def get_public_addr():
     return ip.get_address_in_network(config('ceph-public-network'),
                                      fallback=get_host_ip())
+
+
+def assert_charm_supports_ipv6():
+    """Check whether we are able to support charms ipv6."""
+    if lsb_release()['DISTRIB_CODENAME'].lower() < "trusty":
+        raise Exception("IPv6 is not supported in the charms for Ubuntu "
+                        "versions less than Trusty 14.04")

templates/ceph.conf

@@ -22,6 +22,13 @@ public network = {{ ceph_public_network }}
 cluster network = {{ ceph_cluster_network }}
 {%- endif %}
 
+{% if public_addr %}
+public addr = {{ public_addr }}
+{% endif %}
+{% if cluster_addr %}
+cluster addr = {{ cluster_addr }}
+{%- endif %}
+
 [mon]
 keyring = /var/lib/ceph/mon/$cluster-$id/keyring