1 files changed, 117 insertions, 0 deletions
diff --git a/src/com/google/android/iwlan/epdg/EpdgIkeSaProposal.java b/src/com/google/android/iwlan/epdg/EpdgIkeSaProposal.java
new file mode 100644
index 0000000..f4d6d56
--- /dev/null
+++ b/src/com/google/android/iwlan/epdg/EpdgIkeSaProposal.java
@@ -0,0 +1,117 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.android.iwlan.epdg;
+
+import android.net.ipsec.ike.IkeSaProposal;
+import android.util.Pair;
+
+import java.util.LinkedHashSet;
+
+public class EpdgIkeSaProposal extends EpdgSaProposal {
+    protected final LinkedHashSet<Integer> mProposedPrfAlgos = new LinkedHashSet<>();
+
+    /**
+     * Add proposed PRF algorithms by the carrier.
+     *
+     * @param prfAlgos proposed PRF algorithms
+     */
+    public void addProposedPrfAlgorithm(int[] prfAlgos) {
+        for (int prfAlgo : prfAlgos) {
+            if (validateConfig(prfAlgo, VALID_PRF_ALGOS, CONFIG_TYPE_PRF_ALGO)) {
+                mProposedPrfAlgos.add(prfAlgo);
+            }
+        }
+    }
+
+    private int[] getPrfAlgos() {
+        if (isSaferProposalsPrioritized()) {
+            return mProposedPrfAlgos.stream()
+                    .sorted(
+                            (item1, item2) ->
+                                    compareTransformPriority(VALID_PRF_ALGOS, item1, item2))
+                    .mapToInt(Integer::intValue)
+                    .toArray();
+        }
+
+        return mProposedPrfAlgos.stream().mapToInt(Integer::intValue).toArray();
+    }
+
+    private int[] getSupportedPrfAlgos() {
+        return VALID_PRF_ALGOS.stream().mapToInt(Integer::intValue).toArray();
+    }
+
+    /**
+     * Builds {@link IkeSaProposal} of carrier proposed encryption algorithms (non-AEAD) cipher
+     * suit.
+     */
+    public IkeSaProposal buildProposedIkeSaProposal() {
+        return buildProposal(false, true);
+    }
+
+    /** Builds {@link IkeSaProposal} of carrier proposed AEAD algorithms cipher suit. */
+    public IkeSaProposal buildProposedIkeSaAeadProposal() {
+        return buildProposal(true, true);
+    }
+
+    /**
+     * Builds {@link IkeSaProposal} of Iwlan supported encryption algorithms (non-AEAD) cipher suit.
+     */
+    public IkeSaProposal buildSupportedIkeSaProposal() {
+        return buildProposal(false, false);
+    }
+
+    /** Builds {@link IkeSaProposal} of Iwlan supported AEAD algorithms cipher suit. */
+    public IkeSaProposal buildSupportedIkeSaAeadProposal() {
+        return buildProposal(true, false);
+    }
+
+    private IkeSaProposal buildProposal(boolean isAead, boolean isProposed) {
+        IkeSaProposal.Builder saProposalBuilder = new IkeSaProposal.Builder();
+
+        int[] dhGroups = isProposed ? getDhGroups() : getSupportedDhGroups();
+        for (int dhGroup : dhGroups) {
+            saProposalBuilder.addDhGroup(dhGroup);
+        }
+
+        Pair<Integer, Integer>[] encrAlgos;
+
+        if (isAead) {
+            encrAlgos = (isProposed) ? getAeadAlgos() : getSupportedAeadAlgos();
+        } else {
+            encrAlgos = (isProposed) ? getEncryptionAlgos() : getSupportedEncryptionAlgos();
+        }
+
+        for (Pair<Integer, Integer> encrAlgo : encrAlgos) {
+            saProposalBuilder.addEncryptionAlgorithm(encrAlgo.first, encrAlgo.second);
+        }
+
+        if (!isAead) {
+            int[] integrityAlgos =
+                    (isProposed) ? getIntegrityAlgos() : getSupportedIntegrityAlgos();
+            for (int integrityAlgo : integrityAlgos) {
+                saProposalBuilder.addIntegrityAlgorithm(integrityAlgo);
+            }
+        }
+
+        int[] prfAlgos = (isProposed) ? getPrfAlgos() : getSupportedPrfAlgos();
+        for (int prfAlgo : prfAlgos) {
+            saProposalBuilder.addPseudorandomFunction(prfAlgo);
+        }
+
+        return saProposalBuilder.build();
+    }
+}