fix(network): validate addr length before reading

[oxarbitrage]

Motivation

We want to validate addr length before reading and deserializing the addr itself.

Close #6280

Solution

There is a sizeAddr field in the spec that we can use first to validate. Then we use zcash_deserialize_bytes_external_count to read the address with the length we already have.

Review

Not sure if there is a better alternative. Anyone can review.

We already have tests for this, for example parses_msg_addr_v2_ip.

Reviewer Checklist

• Will the PR name make sense to users?
  • Does it need extra CHANGELOG info? (new features, breaking changes, large changes)
• Are the PR labels correct?
• Does the code do what the ticket and PR says?
  • Does it change concurrent code, unsafe code, or consensus rules?
• How do you know it works? Does it have tests?

Follow Up Work

[codecov]

Codecov Report

Merging #6320 (da2b75c) into main (93c702a) will increase coverage by 0.03%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6320      +/-   ##
==========================================
+ Coverage   77.80%   77.84%   +0.03%     
==========================================
  Files         304      304              
  Lines       39525    39528       +3     
==========================================
+ Hits        30754    30772      +18     
+ Misses       8771     8756      -15     

[upbqdn]

All looks great to me.