Fix parsing of PKCS#8 encoded Elliptic Curve keys.
The relevant ASN.1 definitions for a PKCS#8 encoded Elliptic Curve key are:
PrivateKeyInfo ::= SEQUENCE {
version Version,
privateKeyAlgorithm PrivateKeyAlgorithmIdentifier,
privateKey PrivateKey,
attributes [0] IMPLICIT Attributes OPTIONAL
}
AlgorithmIdentifier ::= SEQUENCE {
algorithm OBJECT IDENTIFIER,
parameters ANY DEFINED BY algorithm OPTIONAL
}
ECParameters ::= CHOICE {
namedCurve OBJECT IDENTIFIER
-- implicitCurve NULL
-- specifiedCurve SpecifiedECDomain
}
ECPrivateKey ::= SEQUENCE {
version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
privateKey OCTET STRING,
parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
publicKey [1] BIT STRING OPTIONAL
}
Because of the two optional fields, there are 4 possible variants that need to
be parsed: no optional fields, only parameters, only public key, and both
optional fields. Previously mbedTLS was unable to parse keys with "only
parameters". Also, only "only public key" was tested. There was a test for "no
optional fields", but it was labelled incorrectly as SEC.1 and not run because
of a great renaming mixup.
diff --git a/tests/data_files/ec_prv.pk8param.pem b/tests/data_files/ec_prv.pk8param.pem
new file mode 100644
index 0000000..978beca
--- /dev/null
+++ b/tests/data_files/ec_prv.pk8param.pem
@@ -0,0 +1,5 @@
+-----BEGIN PRIVATE KEY-----
+MIGTAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBHkwdwIBAQQgx+/F1F/nMZkz0NYVZGG7t1bwXPXP
+NhMhimhr5AKNT5OgCgYIKoZIzj0DAQehRANCAARkJXH1LofHesYJwJkoZQ0ijCVrxDFEi8e/fc1d
+6DS2Hsk55TWpL953QEIDN8RmW01lejceK3jQWs0uGDenGCcM
+-----END PRIVATE KEY-----