lib: Add CRC-8 and CRC-16 checksums

These checksum will be handy for header checksums.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

4 files changed, 208 insertions, 0 deletions

diff --git a/src/lib/tests/CMakeLists.txt b/src/lib/tests/CMakeLists.txt
index 417ec4b0..afe64884 100644
--- a/src/lib/tests/CMakeLists.txt
+++ b/src/lib/tests/CMakeLists.txt
@@ -10,6 +10,8 @@ create_test_sourcelist(${PARENT_DIR}_tests test_suite.c
   auth_test_slh_dsa.c
   bitmap_test.c
   btree_test.c
+  crc8_test.c
+  crc16_test.c
   crc32_test.c
   crc64_test.c
   crypt_test.c
diff --git a/src/lib/tests/crc16_test.c b/src/lib/tests/crc16_test.c
new file mode 100644
index 00000000..03a5b504
--- /dev/null
+++ b/src/lib/tests/crc16_test.c
@@ -0,0 +1,67 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2026
+ *
+ * Test of the CRC-16/CCITT-FALSE function
+ *
+ *    Dimitri Staessens <dimitri@ouroboros.rocks>
+ *    Sander Vrijders   <sander@ouroboros.rocks>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., http://www.fsf.org/about/contact/.
+ */
+
+#include "config.h"
+
+#include <ouroboros/crc16.h>
+
+#include <test/test.h>
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
+/* reveng-catalog smoke vectors. */
+static int test_crc16_ccitt_false_basic(void)
+{
+        uint16_t crc;
+
+        TEST_START();
+
+        crc = 0;
+        crc16_ccitt_false(&crc, "", 0);
+        if (crc != 0xffff)
+                goto fail;
+
+        crc = 0;
+        crc16_ccitt_false(&crc, "123456789", 9);
+        if (crc != 0x29b1)
+                goto fail;
+
+        TEST_SUCCESS();
+        return TEST_RC_SUCCESS;
+ fail:
+        TEST_FAIL();
+        return TEST_RC_FAIL;
+}
+
+int crc16_test(int     argc,
+               char ** argv)
+{
+        int ret = 0;
+
+        (void) argc;
+        (void) argv;
+
+        ret |= test_crc16_ccitt_false_basic();
+        return ret;
+}
diff --git a/src/lib/tests/crc8_test.c b/src/lib/tests/crc8_test.c
new file mode 100644
index 00000000..f7bb33b8
--- /dev/null
+++ b/src/lib/tests/crc8_test.c
@@ -0,0 +1,67 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2026
+ *
+ * Test of the CRC-8/AUTOSAR function
+ *
+ *    Dimitri Staessens <dimitri@ouroboros.rocks>
+ *    Sander Vrijders   <sander@ouroboros.rocks>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., http://www.fsf.org/about/contact/.
+ */
+
+#include "config.h"
+
+#include <ouroboros/crc8.h>
+
+#include <test/test.h>
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
+/* reveng-catalog smoke vectors. */
+static int test_crc8_autosar_basic(void)
+{
+        uint8_t crc;
+
+        TEST_START();
+
+        crc = 0;
+        crc8_autosar(&crc, "", 0);
+        if (crc != 0x00)
+                goto fail;
+
+        crc = 0;
+        crc8_autosar(&crc, "123456789", 9);
+        if (crc != 0xdf)
+                goto fail;
+
+        TEST_SUCCESS();
+        return TEST_RC_SUCCESS;
+ fail:
+        TEST_FAIL();
+        return TEST_RC_FAIL;
+}
+
+int crc8_test(int     argc,
+              char ** argv)
+{
+        int ret = 0;
+
+        (void) argc;
+        (void) argv;
+
+        ret |= test_crc8_autosar_basic();
+        return ret;
+}
diff --git a/src/lib/tests/hash_test.c b/src/lib/tests/hash_test.c
index 19343b17..451d3c25 100644
--- a/src/lib/tests/hash_test.c
+++ b/src/lib/tests/hash_test.c
@@ -39,6 +39,74 @@ struct vec_entry {
         char * out;
 };
 
+static int test_crc8(void)
+{
+        int ret = 0;
+
+        struct vec_entry vec [] = {
+                { "",          "00" },
+                { "123456789", "df" },
+                { NULL,        NULL }
+        };
+
+        struct vec_entry * cur = vec;
+
+        TEST_START();
+
+        while (cur->in != NULL) {
+                uint8_t crc;
+                char    res[3];
+
+                str_hash(HASH_CRC8, &crc, cur->in);
+
+                sprintf(res, "%02x", crc);
+                if (strcmp(res, cur->out) != 0) {
+                        printf("Hash failed %s != %s.\n", res, cur->out);
+                        ret |= -1;
+                }
+
+                ++cur;
+        }
+
+        TEST_END(ret);
+
+        return ret;
+}
+
+static int test_crc16(void)
+{
+        int ret = 0;
+
+        struct vec_entry vec [] = {
+                { "",          "ffff" },
+                { "123456789", "29b1" },
+                { NULL,        NULL   }
+        };
+
+        struct vec_entry * cur = vec;
+
+        TEST_START();
+
+        while (cur->in != NULL) {
+                uint8_t crc[2];
+                char    res[5];
+
+                str_hash(HASH_CRC16, crc, cur->in);
+
+                sprintf(res, "%02x%02x", crc[0], crc[1]);
+                if (strcmp(res, cur->out) != 0) {
+                        printf("Hash failed %s != %s.\n", res, cur->out);
+                        ret |= -1;
+                }
+
+                ++cur;
+        }
+
+        TEST_END(ret);
+
+        return ret;
+}
+
 static int test_crc32(void)
 {
         int ret = 0;
@@ -228,6 +296,10 @@ int hash_test(int     argc,
         (void) argc;
         (void) argv;
 
+        ret |= test_crc8();
+
+        ret |= test_crc16();
+
         ret |= test_crc32();
 
         ret |= test_crc64();