[client, management] Fix the edge cases left open in the certificate posture check (#8174)

shared/management/certposture/certposture_test.go

@@ -2,6 +2,8 @@ package certposture
 
 import (
 	"crypto"
+	"crypto/ecdsa"
+	"crypto/elliptic"
 	"crypto/rand"
 	"crypto/rsa"
 	"crypto/sha256"
@@ -86,6 +88,7 @@ func TestSignVerify_RoundTripPerKeyType(t *testing.T) {
 	ca := certtest.NewCA(t, "root")
 	keys := map[string]crypto.Signer{
 		SigAlgECDSASHA256:  certtest.ECDSAKey(t),
+		SigAlgECDSASHA384:  p384Key(t),
 		SigAlgRSAPSSSHA256: certtest.RSAKey(t),
 		SigAlgEd25519:      certtest.Ed25519Key(t),
 	}
@@ -103,6 +106,24 @@ func TestSignVerify_RoundTripPerKeyType(t *testing.T) {
 	}
 }
 
+func p384Key(t *testing.T) crypto.Signer {
+	t.Helper()
+	key, err := ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
+	require.NoError(t, err)
+	return key
+}
+
+// TestSign_RefusesCurvesTheProofDoesNotName: a proof names its algorithm from the key, and
+// the verifier only knows P-256 and P-384, so P-521 is refused before anything is signed.
+func TestSign_RefusesCurvesTheProofDoesNotName(t *testing.T) {
+	key, err := ecdsa.GenerateKey(elliptic.P521(), rand.Reader)
+	require.NoError(t, err)
+
+	_, _, err = Sign(key, NewChallenger(secret).Nonce(peerKey, now), peerKey)
+
+	assert.ErrorIs(t, err, ErrUnsupportedKey)
+}
+
 func TestVerify_Rejections(t *testing.T) {
 	ca := certtest.NewCA(t, "root")
 	c := NewChallenger(secret)

shared/management/client/grpc_test.go

@@ -12,6 +12,8 @@ import (
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
 
+	"github.com/netbirdio/netbird/client/system"
+	"github.com/netbirdio/netbird/shared/management/certposture"
 	mgmtProto "github.com/netbirdio/netbird/shared/management/proto"
 )
 
@@ -93,3 +95,25 @@ func TestMaxRecvMsgSizeIntegration(t *testing.T) {
 		assert.Len(t, resp.Key, payloadSize)
 	})
 }
+
+// TestInfoToMetaData_CarriesCertificateProofs: management verifies the proofs it receives
+// in the peer meta, so a field dropped by the mapping fails the certificate check without
+// any error on either side.
+func TestInfoToMetaData_CarriesCertificateProofs(t *testing.T) {
+	info := &system.Info{CertificateProofs: []certposture.Proof{
+		{Nonce: []byte("nonce-1"), Chain: [][]byte{[]byte("leaf"), []byte("intermediate")}, SigAlg: "ecdsa-sha256", Signature: []byte("sig-1")},
+		{Nonce: []byte("nonce-2"), Chain: [][]byte{[]byte("other")}, SigAlg: "rsa-pss-sha256", Signature: []byte("sig-2")},
+	}}
+
+	meta := infoToMetaData(info)
+
+	require.Len(t, meta.GetCertificateProofs(), 2, "every proof reaches the meta")
+	first := meta.GetCertificateProofs()[0]
+	assert.Equal(t, []byte("nonce-1"), first.GetNonce())
+	assert.Equal(t, [][]byte{[]byte("leaf"), []byte("intermediate")}, first.GetChain(), "the whole chain is carried, in order")
+	assert.Equal(t, "ecdsa-sha256", first.GetSigAlg())
+	assert.Equal(t, []byte("sig-1"), first.GetSignature())
+	assert.Equal(t, "rsa-pss-sha256", meta.GetCertificateProofs()[1].GetSigAlg())
+
+	assert.Empty(t, infoToMetaData(&system.Info{}).GetCertificateProofs(), "a device without proofs sends none")
+}

shared/management/http/api/openapi.yml

@@ -1821,6 +1821,7 @@ components:
         ca_certificates:
           description: PEM encoded CA certificates the peer's certificate must chain to
           type: array
+          minItems: 1
           items:
             type: string
           example: ["-----BEGIN CERTIFICATE-----\nMIIB...\n-----END CERTIFICATE-----"]