ethertap_user.c 5.4 KB

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  1. /*
  2. * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
  3. * James Leu (jleu@mindspring.net).
  4. * Copyright (C) 2001 by various other people who didn't put their name here.
  5. * Licensed under the GPL.
  6. */
  7. #include <stdio.h>
  8. #include <unistd.h>
  9. #include <stddef.h>
  10. #include <stdlib.h>
  11. #include <sys/errno.h>
  12. #include <sys/socket.h>
  13. #include <sys/wait.h>
  14. #include <sys/un.h>
  15. #include <net/if.h>
  16. #include "user.h"
  17. #include "kern_util.h"
  18. #include "user_util.h"
  19. #include "net_user.h"
  20. #include "etap.h"
  21. #include "os.h"
  22. #include "um_malloc.h"
  23. #define MAX_PACKET ETH_MAX_PACKET
  24. static int etap_user_init(void *data, void *dev)
  25. {
  26. struct ethertap_data *pri = data;
  27. pri->dev = dev;
  28. return 0;
  29. }
  30. struct addr_change {
  31. enum { ADD_ADDR, DEL_ADDR } what;
  32. unsigned char addr[4];
  33. unsigned char netmask[4];
  34. };
  35. static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
  36. int fd)
  37. {
  38. struct addr_change change;
  39. char *output;
  40. int n;
  41. change.what = op;
  42. memcpy(change.addr, addr, sizeof(change.addr));
  43. memcpy(change.netmask, netmask, sizeof(change.netmask));
  44. n = os_write_file(fd, &change, sizeof(change));
  45. if(n != sizeof(change))
  46. printk("etap_change - request failed, err = %d\n", -n);
  47. output = um_kmalloc(page_size());
  48. if(output == NULL)
  49. printk("etap_change : Failed to allocate output buffer\n");
  50. read_output(fd, output, page_size());
  51. if(output != NULL){
  52. printk("%s", output);
  53. kfree(output);
  54. }
  55. }
  56. static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
  57. void *arg)
  58. {
  59. etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
  60. }
  61. static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
  62. void *arg)
  63. {
  64. etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
  65. }
  66. struct etap_pre_exec_data {
  67. int control_remote;
  68. int control_me;
  69. int data_me;
  70. };
  71. static void etap_pre_exec(void *arg)
  72. {
  73. struct etap_pre_exec_data *data = arg;
  74. dup2(data->control_remote, 1);
  75. os_close_file(data->data_me);
  76. os_close_file(data->control_me);
  77. }
  78. static int etap_tramp(char *dev, char *gate, int control_me,
  79. int control_remote, int data_me, int data_remote)
  80. {
  81. struct etap_pre_exec_data pe_data;
  82. int pid, status, err, n;
  83. char version_buf[sizeof("nnnnn\0")];
  84. char data_fd_buf[sizeof("nnnnnn\0")];
  85. char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
  86. char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
  87. data_fd_buf, gate_buf, NULL };
  88. char *nosetup_args[] = { "uml_net", version_buf, "ethertap",
  89. dev, data_fd_buf, NULL };
  90. char **args, c;
  91. sprintf(data_fd_buf, "%d", data_remote);
  92. sprintf(version_buf, "%d", UML_NET_VERSION);
  93. if(gate != NULL){
  94. strcpy(gate_buf, gate);
  95. args = setup_args;
  96. }
  97. else args = nosetup_args;
  98. err = 0;
  99. pe_data.control_remote = control_remote;
  100. pe_data.control_me = control_me;
  101. pe_data.data_me = data_me;
  102. pid = run_helper(etap_pre_exec, &pe_data, args, NULL);
  103. if(pid < 0) err = pid;
  104. os_close_file(data_remote);
  105. os_close_file(control_remote);
  106. n = os_read_file(control_me, &c, sizeof(c));
  107. if(n != sizeof(c)){
  108. printk("etap_tramp : read of status failed, err = %d\n", -n);
  109. return -EINVAL;
  110. }
  111. if(c != 1){
  112. printk("etap_tramp : uml_net failed\n");
  113. err = -EINVAL;
  114. CATCH_EINTR(n = waitpid(pid, &status, 0));
  115. if(n < 0)
  116. err = -errno;
  117. else if(!WIFEXITED(status) || (WEXITSTATUS(status) != 1))
  118. printk("uml_net didn't exit with status 1\n");
  119. }
  120. return err;
  121. }
  122. static int etap_open(void *data)
  123. {
  124. struct ethertap_data *pri = data;
  125. char *output;
  126. int data_fds[2], control_fds[2], err, output_len;
  127. err = tap_open_common(pri->dev, pri->gate_addr);
  128. if(err)
  129. return err;
  130. err = os_pipe(data_fds, 0, 0);
  131. if(err < 0){
  132. printk("data os_pipe failed - err = %d\n", -err);
  133. return err;
  134. }
  135. err = os_pipe(control_fds, 1, 0);
  136. if(err < 0){
  137. printk("control os_pipe failed - err = %d\n", -err);
  138. return err;
  139. }
  140. err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
  141. control_fds[1], data_fds[0], data_fds[1]);
  142. output_len = page_size();
  143. output = um_kmalloc(output_len);
  144. read_output(control_fds[0], output, output_len);
  145. if(output == NULL)
  146. printk("etap_open : failed to allocate output buffer\n");
  147. else {
  148. printk("%s", output);
  149. kfree(output);
  150. }
  151. if(err < 0){
  152. printk("etap_tramp failed - err = %d\n", -err);
  153. return err;
  154. }
  155. pri->data_fd = data_fds[0];
  156. pri->control_fd = control_fds[0];
  157. iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
  158. return data_fds[0];
  159. }
  160. static void etap_close(int fd, void *data)
  161. {
  162. struct ethertap_data *pri = data;
  163. iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
  164. os_close_file(fd);
  165. os_shutdown_socket(pri->data_fd, 1, 1);
  166. os_close_file(pri->data_fd);
  167. pri->data_fd = -1;
  168. os_close_file(pri->control_fd);
  169. pri->control_fd = -1;
  170. }
  171. static int etap_set_mtu(int mtu, void *data)
  172. {
  173. return mtu;
  174. }
  175. static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
  176. void *data)
  177. {
  178. struct ethertap_data *pri = data;
  179. tap_check_ips(pri->gate_addr, addr);
  180. if(pri->control_fd == -1)
  181. return;
  182. etap_open_addr(addr, netmask, &pri->control_fd);
  183. }
  184. static void etap_del_addr(unsigned char *addr, unsigned char *netmask,
  185. void *data)
  186. {
  187. struct ethertap_data *pri = data;
  188. if(pri->control_fd == -1)
  189. return;
  190. etap_close_addr(addr, netmask, &pri->control_fd);
  191. }
  192. const struct net_user_info ethertap_user_info = {
  193. .init = etap_user_init,
  194. .open = etap_open,
  195. .close = etap_close,
  196. .remove = NULL,
  197. .set_mtu = etap_set_mtu,
  198. .add_address = etap_add_addr,
  199. .delete_address = etap_del_addr,
  200. .max_packet = MAX_PACKET - ETH_HEADER_ETHERTAP
  201. };