ec2: Add support for AWS IMDS v2 (session-oriented) (#55)
* ec2: Add support for AWS IMDS v2 (session-oriented)
AWS now supports a new version of fetching Instance Metadata[1].
Update cloud-init's ec2 utility functions and update ec2 derived
datasources accordingly. For DataSourceEc2 (versus ec2-look-alikes)
cloud-init will issue the PUT request to obtain an API token for
the maximum lifetime and then all subsequent interactions with the
IMDS will include the token in the header.
If the API token endpoint is unreachable on Ec2 platform, log a
warning and fallback to using IMDS v1 and which does not use
session tokens when communicating with the Instance metadata
service.
We handle read errors, typically seen if the IMDS is beyond one
etwork hop (IMDSv2 responses have a ttl=1), by setting the api token
to a disabled value and then using IMDSv1 paths.
To support token-based headers, ec2_utils functions were updated
to support custom headers_cb and exception_cb callback functions
so Ec2 could store, or refresh API tokens in the event of token
becoming stale.
tests: Fix cloudsigma tests when no dmidecode data is present. (#57)
The cloudsigma tests had few test cases that were not getting
all the "mocks" set up correctly. Specifically is_running_in_cloudsigma
was not getting replaced and calls would leak through to
util.read_dmi_data.
Add 'accept-ra: true|false' parameter to config v1 and
v2. When True: accept_ra is set to '1'. When False:
accept_ra is set to '0'. When not defined in config the
value is left to the operating system default.
This change also extend the IPv6 support to distinguish
between slaac and dhcpv6-stateless. SLAAC is autoconfig
without any options from DHCP, while stateless auto-configures
the address and the uses DHCP for other options.
Azure's Instance Metadata Service (IMDS) reports multiple IPv6
addresses, via the http://169.254.169.254/metadata/instance/network
route. Any additional values after the first in 'ipAddresses' under the
'ipv6' interface key are extracted and configured as static IPs on
the interface.