tests: add libnet_build_ethernet unit test

Signed-off-by: Valery Ivanov <ivalery111@gmail.com>

2 files changed, 100 insertions, 8 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index fbd5972..a78c578 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -4,4 +4,4 @@ libnet_unit_tests_SOURCES = unit_tests.c
 
 libnet_unit_tests_LDFLAGS = -lcmocka
 
-LDADD = $(top_builddir)/src/libnet.la
\ No newline at end of file
+LDADD = $(top_builddir)/src/libnet.la
diff --git a/tests/unit_tests.c b/tests/unit_tests.c
index 45ad926..c225b37 100644
--- a/tests/unit_tests.c
+++ b/tests/unit_tests.c
@@ -1,21 +1,113 @@
+// clang-format off
+#include <stddef.h>
 #include <stdio.h>
 #include <stdbool.h>
+#include <stdlib.h>
+#include <stdint.h>
 #include <setjmp.h>
 #include <cmocka.h>
 
-/* A test case that does nothing and succeeds. */
-static void bool_always_success(void **state) {
-    (void) state; /* unused */
+#include <libnet.h>
+// clang-format on
 
-    bool this_is_true = true;
+/******************************************************************************
+ *
+ * LOCAL HELPERS
+ *
+ *****************************************************************************/
 
-    assert_true(this_is_true);
+static void
+print_err_buf(const char *err_buf)
+{
+    fprintf(stdout, "[ERROR]: %s\n", err_buf);
+    exit(EXIT_FAILURE);
 }
 
-int main(void) {
+/******************************************************************************
+ *
+ * END OF LOCAL HELPERS
+ *
+ *****************************************************************************/
+
+static void
+test_libnet_build_ethernet(void **state)
+{
+    (void)state;                                    /* unused */
+
+    libnet_ptag_t eth_ptag = (-1);
+    struct libnet_ethernet_hdr *eth_hdr = NULL;
+    char errbuf[LIBNET_ERRBUF_SIZE];
+    uint8_t *header = NULL;
+    uint32_t header_size = 0;
+    uint8_t mac_dst[ETHER_ADDR_LEN] = { 0x11, 0x11, 0x11, 0x22, 0x22, 0x22 };
+    uint8_t mac_src[ETHER_ADDR_LEN] = { 0x44, 0x44, 0x44, 0x55, 0x55, 0x55 };
+    int rv = (-1);
+
+    libnet_t *l = libnet_init(LIBNET_LINK_ADV,  /* enable advanced mode */
+                              NULL,                 /* interface */
+                              errbuf);              /* error buffer */
+
+    if (NULL == l)
+    {
+        print_err_buf(errbuf);
+    }
+    assert_non_null(l);
+
+    eth_ptag = libnet_build_ethernet(mac_dst,       /* destination ethernet address */
+                                     mac_src,       /* source ethernet address */
+                                     ETHERTYPE_IP,  /* upper layer protocol type */
+                                     NULL,          /* payload */
+                                     0,             /* payload length */
+                                     l,             /* libnet context */
+                                     0);            /* protocol tag */
+    if ((-1) == eth_ptag)
+    {
+        print_err_buf(errbuf);
+    }
+    assert_int_not_equal(eth_ptag, (-1));
+
+    rv = libnet_adv_cull_header(l,                  /* libnet context */
+                                eth_ptag,           /* protocol tag */
+                                &header,            /* header */
+                                &header_size);      /* header size */
+    if ((-1) == rv)
+    {
+        print_err_buf(errbuf);
+    }
+    assert_int_not_equal(eth_ptag, (-1));
+    assert_int_not_equal(header_size, 0);
+
+    eth_hdr = (struct libnet_ethernet_hdr *)header;
+    assert_int_equal(eth_hdr->ether_type, htons(ETHERTYPE_IP));
+
+    // Compare source macs
+    for (uint8_t i = 0; i < ETHER_ADDR_LEN; i++)
+    {
+        assert_int_equal(eth_hdr->ether_shost[i], mac_src[i]);
+    }
+
+    // Compare destination macs
+    for (uint8_t i = 0; i < ETHER_ADDR_LEN; i++)
+    {
+        assert_int_equal(eth_hdr->ether_dhost[i], mac_dst[i]);
+    }
+
+    libnet_destroy(l);
+}
+
+int
+main(void)
+{
     const struct CMUnitTest tests[] = {
-        cmocka_unit_test(bool_always_success),
+        cmocka_unit_test(test_libnet_build_ethernet),
     };
 
     return cmocka_run_group_tests(tests, NULL, NULL);
 }
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: nil
+ *  c-file-style: "stroustrup"
+ * End:
+ */