Adding _pwhash_

2020-09-17 18:20:24 +02:00
1 parent 8b26764938
commit 65bf54765f
@@ -0,0 +1,97 @@
+package com.ionspin.kotlin.crypto.pwhash
+
+import com.ionspin.kotlin.crypto.util.toPtr
+import kotlinx.cinterop.addressOf
+import kotlinx.cinterop.convert
+import kotlinx.cinterop.pin
+import libsodium.crypto_pwhash
+import libsodium.crypto_pwhash_str
+import libsodium.crypto_pwhash_str_needs_rehash
+
+actual object PasswordHash {
+    /**
+     * The crypto_pwhash() function derives an outlen bytes long key from a password passwd whose length is passwdlen
+     * and a salt salt whose fixed length is crypto_pwhash_SALTBYTES bytes. passwdlen should be at least crypto_pwhash_
+     * PASSWD_MIN and crypto_pwhash_PASSWD_MAX. outlen should be at least crypto_pwhash_BYTES_MIN = 16 (128 bits) and
+     * at most crypto_pwhash_BYTES_MAX.
+     *
+     * See https://libsodium.gitbook.io/doc/password_hashing/default_phf for more details
+     */
+    actual fun pwhash(
+        outputLength: Int,
+        password: String,
+        salt: UByteArray,
+        opsLimit: ULong,
+        memLimit: Int,
+        algorithm: Int
+    ) : UByteArray {
+        val hashedPassword = UByteArray(outputLength)
+
+        val hashedPasswordPinned = hashedPassword.pin()
+        val saltPinned = salt.pin()
+
+        crypto_pwhash(
+            hashedPasswordPinned.toPtr(),
+            outputLength.convert(),
+            password,
+            password.length.convert(),
+            saltPinned.toPtr(),
+            opsLimit,
+            memLimit.convert(),
+            algorithm
+        )
+        saltPinned.unpin()
+        hashedPasswordPinned.unpin()
+
+        return hashedPassword
+    }
+
+    /**
+     * The crypto_pwhash_str() function puts an ASCII encoded string into out, which includes:
+     * the result of a memory-hard, CPU-intensive hash function applied to the   password passwd of length passwdlen
+     * the automatically generated salt used for the previous computation
+     * the other parameters required to verify the password, including the algorithm identifier, its version, opslimit and memlimit.
+     * out must be large enough to hold crypto_pwhash_STRBYTES bytes, but the actual output string may be shorter.
+     * The output string is zero-terminated, includes only ASCII characters and can be safely stored into SQL databases
+     * and other data stores. No extra information has to be stored in order to verify the password.
+     * The function returns 0 on success and -1 if it didn't complete successfully.
+     */
+    actual fun str(password: String, opslimit: ULong, memlimit: Int): String {
+        val output = ByteArray(crypto_pwhash_STRBYTES.toInt())
+        val outputPinned = output.pin()
+        crypto_pwhash_str(
+            outputPinned.addressOf(0),
+            password,
+            password.length.convert(),
+            opslimit,
+            memlimit.convert()
+        )
+        outputPinned.unpin()
+
+        return output.decodeToString()
+    }
+
+    /**
+     * Check if a password verification string str matches the parameters opslimit and memlimit, and the current default algorithm.
+     * The function returns 1 if the string appears to be correct, but doesn't match the given parameters. In that situation, applications may want to compute a new hash using the current parameters the next time the user logs in.
+     * The function returns 0 if the parameters already match the given ones.
+     * It returns -1 on error. If it happens, applications may want to compute a correct hash the next time the user logs in.
+     */
+    actual fun strNeedsRehash(
+        password: String,
+        opslimit: ULong,
+        memlimit: Int
+    ): Boolean {
+        val password = password.encodeToByteArray()
+        crypto_pwhash_str_needs_rehash(
+            ,
+            opslimit,
+            memlimit.convert()
+        )
+    }
+
+    actual fun strVerify(passwordHash: String, password: UByteArray): Boolean {
+        TODO("Not yet implemented")
+    }
+
+}