1 files changed, 32 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/crypto/prng/drbg/SP80090DRBG.java b/core/src/main/java/org/spongycastle/crypto/prng/drbg/SP80090DRBG.java
new file mode 100644
index 00000000..a1ec3b26
--- /dev/null
+++ b/core/src/main/java/org/spongycastle/crypto/prng/drbg/SP80090DRBG.java
@@ -0,0 +1,32 @@
+package org.spongycastle.crypto.prng.drbg;
+
+/**
+ * Interface to SP800-90A deterministic random bit generators.
+ */
+public interface SP80090DRBG
+{
+    /**
+     * Return the block size of the DRBG.
+     *
+     * @return the block size (in bits) produced by each round of the DRBG.
+     */
+    int getBlockSize();
+
+    /**
+     * Populate a passed in array with random data.
+     *
+     * @param output output array for generated bits.
+     * @param additionalInput additional input to be added to the DRBG in this step.
+     * @param predictionResistant true if a reseed should be forced, false otherwise.
+     *
+     * @return number of bits generated, -1 if a reseed required.
+     */
+    int generate(byte[] output, byte[] additionalInput, boolean predictionResistant);
+
+    /**
+     * Reseed the DRBG.
+     *
+     * @param additionalInput additional input to be added to the DRBG in this step.
+     */
+    void reseed(byte[] additionalInput);
+}