l2_packet_linux.c 4.8 KB

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  1. /*
  2. * WPA Supplicant - Layer2 packet handling with Linux packet sockets
  3. * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
  4. *
  5. * This software may be distributed under the terms of the BSD license.
  6. * See README for more details.
  7. */
  8. #include "includes.h"
  9. #include <sys/ioctl.h>
  10. #include <netpacket/packet.h>
  11. #include <net/if.h>
  12. #include "common.h"
  13. #include "eloop.h"
  14. #include "l2_packet.h"
  15. struct l2_packet_data {
  16. int fd; /* packet socket for EAPOL frames */
  17. char ifname[IFNAMSIZ + 1];
  18. int ifindex;
  19. u8 own_addr[ETH_ALEN];
  20. void (*rx_callback)(void *ctx, const u8 *src_addr,
  21. const u8 *buf, size_t len);
  22. void *rx_callback_ctx;
  23. int l2_hdr; /* whether to include layer 2 (Ethernet) header data
  24. * buffers */
  25. };
  26. int l2_packet_get_own_addr(struct l2_packet_data *l2, u8 *addr)
  27. {
  28. os_memcpy(addr, l2->own_addr, ETH_ALEN);
  29. return 0;
  30. }
  31. int l2_packet_send(struct l2_packet_data *l2, const u8 *dst_addr, u16 proto,
  32. const u8 *buf, size_t len)
  33. {
  34. int ret;
  35. if (l2 == NULL)
  36. return -1;
  37. if (l2->l2_hdr) {
  38. ret = send(l2->fd, buf, len, 0);
  39. if (ret < 0)
  40. wpa_printf(MSG_ERROR, "l2_packet_send - send: %s",
  41. strerror(errno));
  42. } else {
  43. struct sockaddr_ll ll;
  44. os_memset(&ll, 0, sizeof(ll));
  45. ll.sll_family = AF_PACKET;
  46. ll.sll_ifindex = l2->ifindex;
  47. ll.sll_protocol = htons(proto);
  48. ll.sll_halen = ETH_ALEN;
  49. os_memcpy(ll.sll_addr, dst_addr, ETH_ALEN);
  50. ret = sendto(l2->fd, buf, len, 0, (struct sockaddr *) &ll,
  51. sizeof(ll));
  52. if (ret < 0) {
  53. wpa_printf(MSG_ERROR, "l2_packet_send - sendto: %s",
  54. strerror(errno));
  55. }
  56. }
  57. return ret;
  58. }
  59. static void l2_packet_receive(int sock, void *eloop_ctx, void *sock_ctx)
  60. {
  61. struct l2_packet_data *l2 = eloop_ctx;
  62. u8 buf[2300];
  63. int res;
  64. struct sockaddr_ll ll;
  65. socklen_t fromlen;
  66. os_memset(&ll, 0, sizeof(ll));
  67. fromlen = sizeof(ll);
  68. res = recvfrom(sock, buf, sizeof(buf), 0, (struct sockaddr *) &ll,
  69. &fromlen);
  70. if (res < 0) {
  71. wpa_printf(MSG_DEBUG, "l2_packet_receive - recvfrom: %s",
  72. strerror(errno));
  73. return;
  74. }
  75. l2->rx_callback(l2->rx_callback_ctx, ll.sll_addr, buf, res);
  76. }
  77. struct l2_packet_data * l2_packet_init(
  78. const char *ifname, const u8 *own_addr, unsigned short protocol,
  79. void (*rx_callback)(void *ctx, const u8 *src_addr,
  80. const u8 *buf, size_t len),
  81. void *rx_callback_ctx, int l2_hdr)
  82. {
  83. struct l2_packet_data *l2;
  84. struct ifreq ifr;
  85. struct sockaddr_ll ll;
  86. l2 = os_zalloc(sizeof(struct l2_packet_data));
  87. if (l2 == NULL)
  88. return NULL;
  89. os_strlcpy(l2->ifname, ifname, sizeof(l2->ifname));
  90. l2->rx_callback = rx_callback;
  91. l2->rx_callback_ctx = rx_callback_ctx;
  92. l2->l2_hdr = l2_hdr;
  93. l2->fd = socket(PF_PACKET, l2_hdr ? SOCK_RAW : SOCK_DGRAM,
  94. htons(protocol));
  95. if (l2->fd < 0) {
  96. wpa_printf(MSG_ERROR, "%s: socket(PF_PACKET): %s",
  97. __func__, strerror(errno));
  98. os_free(l2);
  99. return NULL;
  100. }
  101. os_memset(&ifr, 0, sizeof(ifr));
  102. os_strlcpy(ifr.ifr_name, l2->ifname, sizeof(ifr.ifr_name));
  103. if (ioctl(l2->fd, SIOCGIFINDEX, &ifr) < 0) {
  104. wpa_printf(MSG_ERROR, "%s: ioctl[SIOCGIFINDEX]: %s",
  105. __func__, strerror(errno));
  106. close(l2->fd);
  107. os_free(l2);
  108. return NULL;
  109. }
  110. l2->ifindex = ifr.ifr_ifindex;
  111. os_memset(&ll, 0, sizeof(ll));
  112. ll.sll_family = PF_PACKET;
  113. ll.sll_ifindex = ifr.ifr_ifindex;
  114. ll.sll_protocol = htons(protocol);
  115. if (bind(l2->fd, (struct sockaddr *) &ll, sizeof(ll)) < 0) {
  116. wpa_printf(MSG_ERROR, "%s: bind[PF_PACKET]: %s",
  117. __func__, strerror(errno));
  118. close(l2->fd);
  119. os_free(l2);
  120. return NULL;
  121. }
  122. if (ioctl(l2->fd, SIOCGIFHWADDR, &ifr) < 0) {
  123. wpa_printf(MSG_ERROR, "%s: ioctl[SIOCGIFHWADDR]: %s",
  124. __func__, strerror(errno));
  125. close(l2->fd);
  126. os_free(l2);
  127. return NULL;
  128. }
  129. os_memcpy(l2->own_addr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
  130. eloop_register_read_sock(l2->fd, l2_packet_receive, l2, NULL);
  131. return l2;
  132. }
  133. void l2_packet_deinit(struct l2_packet_data *l2)
  134. {
  135. if (l2 == NULL)
  136. return;
  137. if (l2->fd >= 0) {
  138. eloop_unregister_read_sock(l2->fd);
  139. close(l2->fd);
  140. }
  141. os_free(l2);
  142. }
  143. int l2_packet_get_ip_addr(struct l2_packet_data *l2, char *buf, size_t len)
  144. {
  145. int s;
  146. struct ifreq ifr;
  147. struct sockaddr_in *saddr;
  148. size_t res;
  149. s = socket(PF_INET, SOCK_DGRAM, 0);
  150. if (s < 0) {
  151. wpa_printf(MSG_ERROR, "%s: socket: %s",
  152. __func__, strerror(errno));
  153. return -1;
  154. }
  155. os_memset(&ifr, 0, sizeof(ifr));
  156. os_strlcpy(ifr.ifr_name, l2->ifname, sizeof(ifr.ifr_name));
  157. if (ioctl(s, SIOCGIFADDR, &ifr) < 0) {
  158. if (errno != EADDRNOTAVAIL)
  159. wpa_printf(MSG_ERROR, "%s: ioctl[SIOCGIFADDR]: %s",
  160. __func__, strerror(errno));
  161. close(s);
  162. return -1;
  163. }
  164. close(s);
  165. saddr = aliasing_hide_typecast(&ifr.ifr_addr, struct sockaddr_in);
  166. if (saddr->sin_family != AF_INET)
  167. return -1;
  168. res = os_strlcpy(buf, inet_ntoa(saddr->sin_addr), len);
  169. if (res >= len)
  170. return -1;
  171. return 0;
  172. }
  173. void l2_packet_notify_auth_start(struct l2_packet_data *l2)
  174. {
  175. }