Manuel Pégourié-Gonnard 9bbe328752 Test each failure mode of pk_parse_key_pkcs1_der()
(Only the top-level ones, ie, for each call to eg asn1_get_mpi(), ensure
there's at least one test case that makes this call fail in one way, but don't
test the various ways to make asn1_get_mpi fail - that should be covered
elsewhere.)

- the new checks added by the previous commits needed exercising
- existing tests sometimes had wrong descriptions or where passing for the
  wrong reason (eg with the "length mismatch" test, the function actually
failed before reaching the length check)
- while at it, add tests for the rest as well

The valid minimal-size key was generated with:

openssl genrsa 128 2>/dev/null | openssl rsa -outform der 2>/dev/null | xxd -p
2020-02-18 10:31:29 +01:00
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2015-04-08 13:25:31 +02:00