On Thu, 11 Apr 2024 12:58:07 GMT, Sergey Chernyshev <[email protected]>
wrote:
>> There are two distinct approaches to parsing IPv4 literal addresses. One is
>> the Java baseline "strict" syntax (all-decimal d.d.d.d form family), another
>> one is the "loose" syntax of RFC 6943 section 3.1.1 [1] (POSIX `inet_addr`
>> allowing octal and hexadecimal forms [2]). The goal of this PR is to provide
>> interface to construct InetAddress objects from literal addresses in POSIX
>> form, to applications that need to mimic the behavior of `inet_addr` used by
>> standard network utilities such as netcat/curl/wget and the majority of web
>> browsers. At present time, there's no way to construct `InetAddress` object
>> from such literal addresses because the existing APIs such as
>> `InetAddress.getByName()`, `InetAddress#ofLiteral()` and
>> `Inet4Address#ofLiteral()` will consume an address and successfully parse it
>> as decimal, regardless of the octal prefix. Hence, the resulting object will
>> point to a different IP address.
>>
>> Historically `InetAddress.getByName()/.getAllByName()` were the only way to
>> convert a literal address into an InetAddress object. `getAllByName()` API
>> relies on POSIX `getaddrinfo` / `inet_addr` which parses IP address segments
>> with `strtoul` (accepts octal and hexadecimal bases).
>>
>> The fallback to `getaddrinfo` is undesirable as it may end up with network
>> queries (blocking mode), if `inet_addr` rejects the input literal address.
>> The Java standard explicitly says that
>>
>> "If a literal IP address is supplied, only the validity of the address
>> format is checked."
>>
>> @AlekseiEfimov contributed JDK-8272215 [3] that adds new factory methods
>> `.ofLiteral()` to `InetAddress` classes. Although the new API is not
>> affected by the `getaddrinfo` fallback issue, it is not sufficient for an
>> application that needs to interoperate with external tooling that follows
>> POSIX standard. In the current state, `InetAddress#ofLiteral()` and
>> `Inet4Address#ofLiteral()` will consume the input literal address and
>> (regardless of the octal prefix) parse it as decimal numbers. Hence, it's
>> not possible to reliably construct an `InetAddress` object from a literal
>> address in POSIX form that would point to the desired host.
>>
>> It is proposed to extend the factory methods with
>> `Inet4Address#ofPosixLiteral()` that allows parsing literal IP(v4) addresses
>> in "loose" syntax, compatible with `inet_addr` POSIX api. The implementation
>> is based on `.isBsdParsableV4()` method added along with JDK-8277608 [4].
>> The changes in the original algorithm are as follows:
>>
>> - `IPAddressUtil#parseB...
>
> Sergey Chernyshev has updated the pull request incrementally with one
> additional commit since the last revision:
>
> moved algorithm description from class spec to the method spec, updated
> code examples to reflect the network byte order
Thanks for taking on the feedback @sercher . I believe we're in a much better
place now. I will let @AlekseiEfimov comment on the test and implementation.
src/java.base/share/classes/java/net/Inet4Address.java line 195:
> 193: * Creates an {@code Inet4Address} based on the provided {@linkplain
> 194: * Inet4Address##format textual representation} of an IPv4 address in
> 195: * POSIX {@code inet_addr} compatible form.
Suggestion:
* Creates an {@code Inet4Address} based on the provided {@linkplain
* Inet4Address##format-posix textual representation of an IPv4 address in
* POSIX {@code inet_addr} compatible form}.
Alternatively you could just remove the link, since the format description is
just below.
src/java.base/share/classes/java/net/Inet4Address.java line 245:
> 243: * {@code IllegalArgumentException}.
> 244: *
> 245: * @param posixIPAddressLiteral the textual representation of an
> IPv4 address.
Suggestion:
* @param posixIPAddressLiteral a textual representation of an IPv4 address.
-------------
PR Review: https://git.openjdk.org/jdk/pull/18493#pullrequestreview-1994510777
PR Review Comment: https://git.openjdk.org/jdk/pull/18493#discussion_r1561205498
PR Review Comment: https://git.openjdk.org/jdk/pull/18493#discussion_r1561210422
