summaryrefslogtreecommitdiff
path: root/src/network.c
blob: 122676d9f600afd10240a46f5befb6317774cf56 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
#include "junk/network.h"
#include <arpa/inet.h>
#include <net/if.h>
#include <errno.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#include <net/ethernet.h> /* the L2 protocols */
#include <netdb.h>
#include <netinet/in.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>

#define TAG "network"

int tcp_ipv4_send(char *ip, char *port, char *data) {

  int sock;
  struct addrinfo hints, *p, *res;

  memset(&hints, 0, sizeof hints);
  hints.ai_family = AF_INET;
  hints.ai_socktype = SOCK_STREAM;

  if (getaddrinfo(ip, port, &hints, &res) != 0) {
    fprintf(stderr, "%s: getaddrinfo (%d): %s\n", TAG, errno,
            gai_strerror(errno));
    return errno;
  }

  if ((sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol)) ==
      -1) {
    fprintf(stderr, "%s: socket (%d): %s\n", TAG, errno, strerror(errno));
    return errno;
  }

  if (connect(sock, res->ai_addr, res->ai_addrlen) == -1) {
    fprintf(stderr, "%s: connect (%d): %s\n", TAG, errno, strerror(errno));
    return errno;
  }

  int len = strlen(data);
  int bytes_sent = 0;
  int total_bytes_sent = 0;

  while (1) {
    if ((bytes_sent = send(sock, data, len, 0)) == -1) {
      fprintf(stderr, "%s: send (%d): %s\n", TAG, errno, strerror(errno));
      return errno;
    }
    total_bytes_sent += bytes_sent;
    if (bytes_sent == len) {
      break;
    }
  }
  close(sock);
  freeaddrinfo(res);
  return 0;
}

/* eth_arp_bind
 * Bind to a L2 Ethernet address.
 *
 */
int eth_arp_bind(char address[]) {

  int sock;
  struct sockaddr_ll addrinfo;

  if ((sock = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ARP))) == -1) {
    fprintf(stderr, "%s: socket (%d): %s\n", TAG, errno, strerror(errno));
    return errno;
  }
  fprintf(stderr, "%s: socket fd: (%d)\n", TAG, sock);

  memset(&addrinfo, 0, sizeof addrinfo);
  addrinfo.sll_family = AF_PACKET;
  addrinfo.sll_protocol = htons(ETH_P_ARP);
  addrinfo.sll_ifindex = 0;
  addrinfo.sll_pkttype = PACKET_BROADCAST;
  sscanf((char *)address, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
         &addrinfo.sll_addr[0], &addrinfo.sll_addr[1], &addrinfo.sll_addr[2],
         &addrinfo.sll_addr[3], &addrinfo.sll_addr[4], &addrinfo.sll_addr[5]);
  addrinfo.sll_halen = 6;

  fprintf(stderr, "%s: target mac (%02x:%02x:%02x:%02x:%02x:%02x)\n", TAG,
          addrinfo.sll_addr[0], addrinfo.sll_addr[1], addrinfo.sll_addr[2],
          addrinfo.sll_addr[3], addrinfo.sll_addr[4], addrinfo.sll_addr[5]);

  int status = 0;
  if ((status = bind(sock, (struct sockaddr *)&addrinfo, sizeof(addrinfo))) !=
      0) {
    fprintf(stderr, "%s: bind (%d): %s\n", TAG, errno, strerror(errno));
    return status;
  }

  return sock;
}

/* eth_arp_recv
 * Recv on a L2 Ethernet address.
 *
 */
int eth_arp_recv(int sockfd, arp_packet *packet) {
  int buffer_len = sizeof(ethhdr) + sizeof(arp_packet);
  char buffer[buffer_len];
  memset(buffer, 0, buffer_len);
  int bytes_read = 0;
  int total_bytes_read = 0;

  while (1) {
    bytes_read = recv(sockfd, &buffer[total_bytes_read],
                      buffer_len - total_bytes_read, 0);
    if (bytes_read == -1) {
      fprintf(stderr, "%s: recv (%d): %s\n", TAG, errno, strerror(errno));
      return -1;
    } else if (bytes_read > 0) {
      fprintf(stderr, "%s: recv: read %d bytes, total %d\n", TAG, bytes_read,
              total_bytes_read);
      total_bytes_read += bytes_read;
    } else {

      ethhdr *recv_struct = (ethhdr *)buffer;
      fprintf(stderr, "%s: source mac (%02x:%02x:%02x:%02x:%02x:%02x)\n", TAG,
              recv_struct->h_source[0], recv_struct->h_source[1],
              recv_struct->h_source[2], recv_struct->h_source[3],
              recv_struct->h_source[4], recv_struct->h_source[5]);
      fprintf(stderr, "%s: dest mac (%02x:%02x:%02x:%02x:%02x:%02x)\n", TAG,
              recv_struct->h_dest[0], recv_struct->h_dest[1],
              recv_struct->h_dest[2], recv_struct->h_dest[3],
              recv_struct->h_dest[4], recv_struct->h_dest[5]);

      memcpy((char *)packet, (char *)(buffer + sizeof(ethhdr)),
             sizeof(arp_packet));
      return 0;
    }
  }
}

int eth_arp_send(int sockfd, arp_packet *packet) {
  char buffer[sizeof(ethhdr) + sizeof(arp_packet)];
  memset(buffer, 0, sizeof(buffer));
  ethhdr *eth_header = (ethhdr *)buffer;
  memcpy(eth_header->h_source, packet->sender_hardware_address,
         sizeof(packet->sender_hardware_address));
  memcpy(eth_header->h_dest, packet->target_hardware_address,
         sizeof(packet->target_hardware_address));
  eth_header->h_proto = htons(ETH_P_ARP);
  memcpy(buffer + sizeof(ethhdr), packet, sizeof(arp_packet));

  struct sockaddr_ll addrinfo;
  memset(&addrinfo, 0, sizeof addrinfo);
  addrinfo.sll_family = AF_PACKET;
  addrinfo.sll_protocol = htonl(ETH_P_ARP);
  addrinfo.sll_ifindex = if_nametoindex("enp6s0");
  addrinfo.sll_hatype = htonl(ARPHRD_ETHER);
  addrinfo.sll_pkttype = PACKET_BROADCAST;
  addrinfo.sll_halen = 6;
  memcpy(addrinfo.sll_addr, packet->target_hardware_address, sizeof(packet->target_hardware_address));

 fprintf(stderr, "network: send to %hhx:%hhx:%hhx:%hhx:%hhx:%hhx\n", addrinfo.sll_addr[0],addrinfo.sll_addr[1],addrinfo.sll_addr[2],addrinfo.sll_addr[3],addrinfo.sll_addr[4],addrinfo.sll_addr[5]);

  int bytes_sent = 0;
  int total_bytes_sent = 0;
  while (1) {
    bytes_sent = sendto(sockfd, buffer + total_bytes_sent,
                      sizeof(buffer) - total_bytes_sent, 0, (struct sockaddr*)&addrinfo, sizeof(addrinfo));

    if (bytes_sent == -1) {
      fprintf(stderr, "%s: send (%d): %s\n", TAG, errno, strerror(errno));
      return -1;
    } else if (bytes_sent < sizeof(buffer)) {
      fprintf(stderr, "%s: send: sent %d bytes, total %d\n", TAG, bytes_sent,
              total_bytes_sent);
      total_bytes_sent += bytes_sent;
    } else {
      fprintf(stderr, "%s: send: sent %d bytes, total %d\n", TAG, bytes_sent,
              total_bytes_sent);
      return 0;
    }
  }
}