When a container is connected to a network, it gets /etc/hosts
entries for its addresses on that network. So, when it's connected
to two networks, it has a hosts entry for each. For example, if
the hostname is the default short-id and it's connected to two
networks (172.19.0.0/16 and 172.20.0.0/17, plus IPv6 address for
each), the hosts file might include:
172.19.0.2 4b92a573912d
fd8c:c894:d68::2 4b92a573912d
172.20.0.2 4b92a573912d
fd8c:c894:d68:1::2 4b92a573912d
If the container is disconnected from 172.19.0.2, only remove
the hosts entries with addresses on that network.
Signed-off-by: Rob Murray <rob.murray@docker.com>
The `mergeRecords` function wasn't actually _merging_ anything, but only
appended records to the existing `/etc/hosts` content. However, doing so
was split across two functions; `Add` and `mergeRecords()`;
- `Add()` obtains a lock for the given path
- then calls `mergeRecords` which reads the file-content and appends the
new records to the content.
- Closes the file and returns the new content
- Then `Add` does a `os.WriteFile` to ... the same file
Given that we're appending, we won't have to read the file's content, and
we can append to the file itself.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This regex is constructed using user-input, which could technically
produce an invalid regex.
Given that we have an error-return to our availability, let's return
any error we get, instead of panicking.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Also, libnetwork: Sandbox.buildHostsFile: rename var that shadowed type
Co-authored-by: Sebastiaan van Stijn <github@gone.nl>
Signed-off-by: Rob Murray <rob.murray@docker.com>
Also, return IPv6 records from Network.getSvcRecords()
so that /etc/hosts entries are deleted when an IPv6-only
endpoint is removed.
Signed-off-by: Rob Murray <rob.murray@docker.com>
Some configuration in a container depends on whether it has support for
IPv6 (including default entries for '::1' etc in '/etc/hosts').
Before this change, the container's support for IPv6 was determined by
whether it was connected to any IPv6-enabled networks. But, that can
change over time, it isn't a property of the container itself.
So, instead, detect IPv6 support by looking for '::1' on the container's
loopback interface. It will not be present if the kernel does not have
IPv6 support, or the user has disabled it in new namespaces by other
means.
Once IPv6 support has been determined for the container, its '/etc/hosts'
is re-generated accordingly.
The daemon no longer disables IPv6 on all interfaces during initialisation.
It now disables IPv6 only for interfaces that have not been assigned an
IPv6 address. (But, even if IPv6 is disabled for the container using the
sysctl 'net.ipv6.conf.all.disable_ipv6=1', interfaces connected to IPv6
networks still get IPv6 addresses that appear in the internal DNS. There's
more to-do!)
Signed-off-by: Rob Murray <rob.murray@docker.com>
libnetwork/etchosts/etchosts_test.go:167:54: empty-lines: extra empty line at the end of a block (revive)
libnetwork/osl/route_linux.go:185:74: empty-lines: extra empty line at the start of a block (revive)
libnetwork/osl/sandbox_linux_test.go:323:36: empty-lines: extra empty line at the start of a block (revive)
libnetwork/bitseq/sequence.go:412:48: empty-lines: extra empty line at the start of a block (revive)
libnetwork/datastore/datastore_test.go:67:46: empty-lines: extra empty line at the end of a block (revive)
libnetwork/datastore/mock_store.go:34:60: empty-lines: extra empty line at the end of a block (revive)
libnetwork/iptables/firewalld.go:202:44: empty-lines: extra empty line at the end of a block (revive)
libnetwork/iptables/firewalld_test.go:76:36: empty-lines: extra empty line at the end of a block (revive)
libnetwork/iptables/iptables.go:256:67: empty-lines: extra empty line at the end of a block (revive)
libnetwork/iptables/iptables.go:303:128: empty-lines: extra empty line at the start of a block (revive)
libnetwork/networkdb/cluster.go:183:72: empty-lines: extra empty line at the end of a block (revive)
libnetwork/ipams/null/null_test.go:44:38: empty-lines: extra empty line at the end of a block (revive)
libnetwork/drivers/macvlan/macvlan_store.go:45:52: empty-lines: extra empty line at the end of a block (revive)
libnetwork/ipam/allocator_test.go:1058:39: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/bridge/port_mapping.go:88:111: empty-lines: extra empty line at the end of a block (revive)
libnetwork/drivers/bridge/link.go:26:90: empty-lines: extra empty line at the end of a block (revive)
libnetwork/drivers/bridge/setup_ipv6_test.go:17:34: empty-lines: extra empty line at the end of a block (revive)
libnetwork/drivers/bridge/setup_ip_tables.go:392:4: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/bridge/bridge.go:804:50: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/overlay/ov_serf.go:183:29: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/overlay/ov_utils.go:81:64: empty-lines: extra empty line at the end of a block (revive)
libnetwork/drivers/overlay/peerdb.go:172:67: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/overlay/peerdb.go:209:67: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/overlay/peerdb.go:344:89: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/overlay/peerdb.go:436:63: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/overlay/overlay.go:183:36: empty-lines: extra empty line at the start of a block (revive)
libnetwork/drivers/overlay/encryption.go:69:28: empty-lines: extra empty line at the end of a block (revive)
libnetwork/drivers/overlay/ov_network.go:563:81: empty-lines: extra empty line at the start of a block (revive)
libnetwork/default_gateway.go:32:43: empty-lines: extra empty line at the start of a block (revive)
libnetwork/errors_test.go:9:40: empty-lines: extra empty line at the start of a block (revive)
libnetwork/service_common.go:184:64: empty-lines: extra empty line at the end of a block (revive)
libnetwork/endpoint.go:161:55: empty-lines: extra empty line at the end of a block (revive)
libnetwork/store.go:320:33: empty-lines: extra empty line at the end of a block (revive)
libnetwork/store_linux_test.go:11:38: empty-lines: extra empty line at the end of a block (revive)
libnetwork/sandbox.go:571:36: empty-lines: extra empty line at the start of a block (revive)
libnetwork/service_common.go:317:246: empty-lines: extra empty line at the start of a block (revive)
libnetwork/endpoint.go:550:17: empty-lines: extra empty line at the end of a block (revive)
libnetwork/sandbox_dns_unix.go:213:106: empty-lines: extra empty line at the start of a block (revive)
libnetwork/controller.go:676:85: empty-lines: extra empty line at the end of a block (revive)
libnetwork/agent.go:876:60: empty-lines: extra empty line at the end of a block (revive)
libnetwork/resolver.go:324:69: empty-lines: extra empty line at the end of a block (revive)
libnetwork/network.go:1153:92: empty-lines: extra empty line at the end of a block (revive)
libnetwork/network.go:1955:67: empty-lines: extra empty line at the start of a block (revive)
libnetwork/network.go:2235:9: empty-lines: extra empty line at the start of a block (revive)
libnetwork/libnetwork_internal_test.go:336:26: empty-lines: extra empty line at the start of a block (revive)
libnetwork/resolver_test.go:76:35: empty-lines: extra empty line at the end of a block (revive)
libnetwork/libnetwork_test.go:303:38: empty-lines: extra empty line at the end of a block (revive)
libnetwork/libnetwork_test.go:985:46: empty-lines: extra empty line at the end of a block (revive)
libnetwork/ipam/allocator_test.go:1263:37: empty-lines: extra empty line at the start of a block (revive)
libnetwork/errors_test.go:9:40: empty-lines: extra empty line at the end of a block (revive)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The io/ioutil package has been deprecated in Go 1.16. This commit
replaces the existing io/ioutil functions with their new definitions in
io and os packages.
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
Perhaps the testutils package in the past had an `init()` function to set up
specific things, but it no longer has. so these imports were doing nothing.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
After moving libnetwork to this repo, we need to update all the import
paths for libnetwork to point to docker/docker/libnetwork instead of
docker/libnetwork.
This change implements that.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
This approach allows the user to provide a FQDN as hostname if that is what
they want in their container, or to provide distinct host and domain parts. In
both cases we will correctly extract the first token for /etc/hosts.
Signed-off-by: Tim Hockin <thockin@google.com>
Introduced a path level lock to synchronize updates
to /etc/hosts writes. A path level cache is maintained
to only synchronize only at the file level.
Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
This way we won't vendor test related functions in docker anymore.
It also moves netns related functions to a new ns package to be able to
call the ns init function in tests. I think this also helps with the
overall package isolation.
Signed-off-by: David Calavera <david.calavera@gmail.com>
There is no need to update the /etc/hosts files
of containers for endpoints which are created/deleted
in a network whose interface list is empty
Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
Currently the etchosts package only provides helpers
to completely build an /etc/hosts file from scratch
or update a single hostname's IP address to a different
one. This commit adds the ability to add/delete an arbitrary
number of host record entries to/from the etc hosts file
Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>
