NIFI-14068 Fix Domain Name Handling for SFTP Proxy Access

[exceptionfactory]

Summary

NIFI-14068 Corrects the behavior of SFTP processors when configured for proxy access using a DNS name.

The current implementation of the SSHJ SSHClient always attempts to resolve DNS names to IP addresses when constructing an InetSocketAddress for the socket connection. This behavior is not ideal when connecting through a proxy server because NiFi may not be able to resolve the DNS address and should rely on the proxy server to perform DNS resolution.

The revised implementation introduces an extension of SSHClient that overrides the makeInetSocketAddress method to return an unresolved address when the client is configured with a Proxy Socket Factory. The unresolved status instructs HTTP and SOCKS proxy socket clients to send a DNS address instead of a resolved IP address.

Tracking

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Issue Tracking

• Apache NiFi Jira issue created

Pull Request Tracking

• Pull Request title starts with Apache NiFi Jira issue number, such as NIFI-00000
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Build

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  • JDK 21

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