kernel: net: Implement IEEE 802.3 + ARP requests

Introduce IEEE 802.3 related headers such as ones containing the
structure of an ethernet frame as well as its types. This commit
additionally introduces ARP request logic.

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 55 insertions, 0 deletions

diff --git a/sys/include/netinet/if_ether.h b/sys/include/netinet/if_ether.h
new file mode 100644
index 0000000..571622d
--- /dev/null
+++ b/sys/include/netinet/if_ether.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _NETINET_IF_ETHER_H_
+#define _NETINET_IF_ETHER_H_
+
+#include <sys/types.h>
+#include <net/if_arp.h>
+#include <net/if_var.h>
+
+#define ETHER_ADDR_LEN 6
+
+struct ether_arp {
+    struct arp_hdr hdr;
+    uint8_t sha[ETHER_ADDR_LEN];
+    uint8_t spa[4];
+    uint8_t tha[ETHER_ADDR_LEN];
+    uint8_t tpa[4];
+};
+
+struct ether_frame {
+    uint8_t ether_daddr[ETHER_ADDR_LEN];
+    uint8_t ether_saddr[ETHER_ADDR_LEN];
+    uint16_t ether_type;
+};
+
+int arp_request(struct netif *nifp, uint8_t *sproto, uint8_t *tproto);
+
+#endif  /* !_NETINET_IF_ETHER_H_ */