fix(network_info_plus): Fix subnet mask and broadcast on Linux

[source-creator]

Description

On Linux, an incorrect subnet mask and broadcast mask is returned if the network prefix is not byte aligned.

For example, a prefix of /24 works, but /22 doesn't.
This is due to incorrect bit operations in addition to incorrect byte ordering in the Linux Dart code, where network byte order should rather be used.

The current code:

  final prefix = 22;
  final mask = 0xffffffff >> (32 - prefix);
  // mask == 4194303 == 0.63.255.255

The updated code:

  final prefix = 22;
  final mask = (0xffffffff << (32 - prefix)) & 0xffffffff;
  // mask == 4294966272 == 255.255.252.0

The network byte order is defined to always be big-endian, which may differ from the host byte order on a particular machine. Using network byte ordering for data exchanged between hosts allows hosts using different architectures to exchange address information without confusion because of byte ordering.

Source: https://www.ibm.com/docs/en/zvm/7.4.0?topic=domains-network-byte-order-host-byte-order

Related Issues

fixes: #3941

Checklist

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• I titled the PR using Conventional Commits.
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Breaking Change

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• Yes, this is a breaking change (please indicate that with a ! in the title as explained in Conventional Commits).
• No, this is not a breaking change.