This commit adds template `Fill<ObjectType>(ObjectType &aObject)`
functions for both `Crypto` and `NonCrypto` random number generation
modules. These functions fill a given object with random byes.
With NAT64, we need to handle the IPv4 packets inside the border
router functions in OpenThread core.
This commit introduces a few new classes for NAT64:
- Add `Ip4::Cidr` (for specifying CIDR block of translated packets)
- Updated Ip4 address format -- use a union of (m8[4], m16[2], m32)
instead of 4 bytes.
- Extend `Checksum` for supporting ICMP in Ip4 (and TCP4 / UDP4) and
IPv4 header.
This commit updates `VerifyOrQuit()` and `SuccessOrQuit()` macros to
include the failed condition in the error message that is printed on
a failure (in addition to function name and line number where the
error happened). This commit also changes the second parameter
(`aMessage`) to in these macros to be optional.
This commit also updates unit tests to remove the second `aMessage`
string in cases where the failure can be inferred from the condition
itself.
This commit adds a new core header files `common/error.hpp` which
defines `ot::Error` (mirroring `otError`) and `kError{Name}` constants
(mirroring the public `OT_ERROR_{NAME}` definitions). The new (C++
style) definitions are used by core modules. This commit also moves
`otThreadErrorToString()` (from `logging.hpp` to `error.hpp`) and
renames it to `ErrorToString()` which is used as the internal (to
core) function to covert an `Error` to a string.
This commit adds new helper methods in `Message` class. It adds new
template methods to allow an object (of any type) to be read from or
written/appended/prepended to the message. The `Read<ObjectType>()`
method returns a parse `otError` if there are not enough bytes
remaining in the message to read the entire object.
The template methods are used in other core modules which help
simplify the code (there is no need to specify the template type since
it can be deduced by the complier from the passed-in argument). Also
since the template methods directly use the `sizeof` the object type,
they help reduce the chance of incorrect use (using incorrect
read/write length when calling the method).
This commit also updates and renames the methods which read/write raw
bytes from/to the message to `ReadBytes()`/`WriteBytes()`. The order
of parameters in these methods are changed to follow the common
pattern used by other modules and the OT public APIs (i.e., the
pointer to the buffer is given first, followed by its length).
This commit adds `Checksum` class which implements IP checksum
calculation and verification (all related code from other modules is
now moved to `Checksum` class). The new checksum calculation allows
any message chunk size (removes a limitation with previous model
of requiring even sized chunks). This commit also adds a unit test
`test_checksum` covering the behavior of `Checksum` methods.
Abtin Keshavarzian