auth: better RFC3597 conformance

[miodvallat]

Short description

This rewrites the parsing of unknown records (TYPEnnn \# n xxxxxx) to allow for the binary data to contain whitespace between pairs of digits (i.e. allow xx xx xx or xxxx xxxx or xx xxxxxx xx but not x x).

I also tried to make the error messages, in case of ill-formed data, more useful.

Checklist

I have:

• read the CONTRIBUTING.md document
• read and accepted the Developer Certificate of Origin document, including the AI Policy, and added a "Signed-off-by" to my commits
• compiled this code
• tested this code
• included documentation (including possible behaviour changes)
• documented the code
• added or modified regression test(s)
• added or modified unit test(s)

[coveralls]

Coverage Report for CI Build 29592118544

Coverage increased (+0.002%) to 71.138%

Details

• Coverage increased (+0.002%) from the base build.
• Patch coverage: 5 uncovered changes across 1 file (73 of 78 lines covered, 93.59%).
• 59 coverage regressions across 15 files.

Uncovered Changes

File	Changed	Covered	%
pdns/dnsparser.cc	71	66	92.96%
Total (2 files)	78	73	93.59%

Coverage Regressions

59 previously-covered lines in 15 files lost coverage.

Top 10 Files by Coverage Loss	Lines Losing Coverage	Coverage
pdns/recursordist/rec-tcp.cc	10	69.95%
pdns/misc.cc	8	61.94%
pdns/recursordist/syncres.cc	8	81.32%
pdns/recursordist/test-syncres_cc1.cc	5	80.29%
pdns/dnsdistdist/dnsdist-carbon.cc	4	59.56%
modules/gpgsqlbackend/spgsql.cc	3	63.56%
pdns/recursordist/aggressive_nsec.cc	3	66.05%
pdns/recursordist/pdns_recursor.cc	3	75.62%
pdns/recursordist/test-syncres_cc2.cc	3	79.39%
pdns/remote_logger.cc	3	57.14%

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Coverage Stats

Relevant Lines:	172068
Covered Lines:	134187
Line Coverage:	77.98%
Relevant Branches:	82288
Covered Branches:	46758
Branch Coverage:	56.82%
Branches in Coverage %:	Yes
Coverage Strength:	6536146.95 hits per line

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💛 - Coveralls