From 27e0133d40f7b328482b501a18e22b12a55564ea Mon Sep 17 00:00:00 2001
From: Star Rauchenberger <fefferburbia@gmail.com>
Date: Sun, 13 Jul 2025 10:07:59 -0400
Subject: Associate

---
 src/transmit.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)
 create mode 100644 src/transmit.c

(limited to 'src/transmit.c')

diff --git a/src/transmit.c b/src/transmit.c
new file mode 100644
index 0000000..1978ff2
--- /dev/null
+++ b/src/transmit.c
@@ -0,0 +1,55 @@
+#include "transmit.h"
+
+#include <libwifi.h>
+#include <linux/if_packet.h>
+#include <netinet/ether.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static pthread_mutex_t socket_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+int send_packet(int sock, int device_index, const unsigned char dst_addr[6], const unsigned char *packet, int packet_size)
+{
+  struct sockaddr_ll socket_address;
+  socket_address.sll_ifindex = device_index;
+  socket_address.sll_halen = ETH_ALEN;
+  memcpy(socket_address.sll_addr, dst_addr, 6);
+
+  pthread_mutex_lock(&socket_mutex);
+
+  int ret = 0;
+  if (sendto(sock, packet, packet_size, 0, (struct sockaddr *)&socket_address, sizeof(struct sockaddr_ll)) < 0)
+  {
+    printf("Could not send packet: %d\n", errno);
+    ret = errno;
+  }
+
+  pthread_mutex_unlock(&socket_mutex);
+
+  return ret;
+}
+
+int send_packet_with_radiotap(int sock, int device_index, const unsigned char dst_addr[6], const unsigned char* packet, int packet_size)
+{
+  struct libwifi_radiotap_info radiotap_info = {0};
+  radiotap_info.present = (1 << IEEE80211_RADIOTAP_FLAGS) | (1 << IEEE80211_RADIOTAP_RATE);
+  radiotap_info.flags = IEEE80211_RADIOTAP_F_FCS | IEEE80211_RADIOTAP_F_SHORTPRE;
+  radiotap_info.rate_raw = 4;
+
+  unsigned char radiotap_buffer[256];
+  int radiotap_size = libwifi_create_radiotap(&radiotap_info, radiotap_buffer);
+  
+  uint32_t fcs = libwifi_calculate_fcs(packet, packet_size);
+
+  int buffer_size = radiotap_size + packet_size + sizeof(uint32_t);
+  unsigned char* buffer = (unsigned char*)malloc(buffer_size);
+
+  memcpy(buffer, radiotap_buffer, radiotap_size);
+  memcpy(buffer + radiotap_size, packet, packet_size);
+  memcpy(buffer + radiotap_size + packet_size, (unsigned char*)&fcs, sizeof(uint32_t));
+
+  int ret = send_packet(sock, device_index, dst_addr, buffer, buffer_size);
+
+  return ret;
+}
-- 
cgit 1.4.1