datagram.c 1.7 KB

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  1. /*
  2. * common UDP/RAW code
  3. * Linux INET implementation
  4. *
  5. * Authors:
  6. * Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
  7. *
  8. * This program is free software; you can redistribute it and/or
  9. * modify it under the terms of the GNU General Public License
  10. * as published by the Free Software Foundation; either version
  11. * 2 of the License, or (at your option) any later version.
  12. */
  13. #include <linux/types.h>
  14. #include <linux/module.h>
  15. #include <linux/ip.h>
  16. #include <linux/in.h>
  17. #include <net/ip.h>
  18. #include <net/sock.h>
  19. #include <net/route.h>
  20. #include <net/tcp_states.h>
  21. int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
  22. {
  23. struct inet_sock *inet = inet_sk(sk);
  24. struct sockaddr_in *usin = (struct sockaddr_in *) uaddr;
  25. struct rtable *rt;
  26. __be32 saddr;
  27. int oif;
  28. int err;
  29. if (addr_len < sizeof(*usin))
  30. return -EINVAL;
  31. if (usin->sin_family != AF_INET)
  32. return -EAFNOSUPPORT;
  33. sk_dst_reset(sk);
  34. oif = sk->sk_bound_dev_if;
  35. saddr = inet->saddr;
  36. if (MULTICAST(usin->sin_addr.s_addr)) {
  37. if (!oif)
  38. oif = inet->mc_index;
  39. if (!saddr)
  40. saddr = inet->mc_addr;
  41. }
  42. err = ip_route_connect(&rt, usin->sin_addr.s_addr, saddr,
  43. RT_CONN_FLAGS(sk), oif,
  44. sk->sk_protocol,
  45. inet->sport, usin->sin_port, sk, 1);
  46. if (err)
  47. return err;
  48. if ((rt->rt_flags & RTCF_BROADCAST) && !sock_flag(sk, SOCK_BROADCAST)) {
  49. ip_rt_put(rt);
  50. return -EACCES;
  51. }
  52. if (!inet->saddr)
  53. inet->saddr = rt->rt_src; /* Update source address */
  54. if (!inet->rcv_saddr)
  55. inet->rcv_saddr = rt->rt_src;
  56. inet->daddr = rt->rt_dst;
  57. inet->dport = usin->sin_port;
  58. sk->sk_state = TCP_ESTABLISHED;
  59. inet->id = jiffies;
  60. sk_dst_set(sk, &rt->u.dst);
  61. return(0);
  62. }
  63. EXPORT_SYMBOL(ip4_datagram_connect);