Multiple fixes from Fenrir report

[danielinux]

• F/324 Prevent accepting datagrams from any source after UDP connected
• F/329: TCP: double check ISNs in 3WHS before stepping into state ESTABLISHED
• F/330: TCP: check in-window / correct seq on received RST (enforce RFC5961 behavior for RST handling)
• F/325: Rejected as false positive, test added
• F/391: TCP: Correctly resetting CB_READABLE flags in TCP_CLOSE_WAIT state
• F/393: UDP connect: validate sin->sin_family and addrlen
• F/331: Added a guard to skip TTL-exceeded generation on short packets
• F/394: TCP SACK: use tcp_seq_lt instead of '<' to prevent overflows
• F/326 DNS: Remove redundant snprintf
• F/390: Remove RTO cancel/reset in tcp_recv
• F/332: DNS minimum hdr size validation
• F/392: DNS cosmetic changes

[Copilot]

Pull request overview

This PR addresses issues reported by Fenrir around socket “connection” semantics: ensuring UDP connected sockets only accept datagrams from the connected peer, and tightening TCP 3-way handshake validation before transitioning to TCP_ESTABLISHED.

Changes:

• Fix UDP receive-side socket matching to enforce connected-peer source IP filtering.
• Add additional TCP sequence/acknowledgement validation in SYN_SENT/SYN_RCVD, plus stricter RST handling.
• Update and extend unit tests to cover the new UDP/TCP behaviors.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
src/wolfip.c	Updates UDP demux rules for connected sockets; adds TCP handshake ACK/SEQ checks and RST sequence validation logic.
src/test/unit/unit.c	Adjusts existing tests for new handshake expectations and adds new tests for invalid SYN-ACK ACK rejection, RST handling, and UDP connected wrong-source rejection.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 5 comments.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

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