include/linux/ipsec.h

   1 /*
   2  *      Definitions for the SECurity layer
   3  *
   4  *      Author:
   5  *              Robert Muchsel <muchsel@acm.org>
   6  *
   7  *      This program is free software; you can redistribute it and/or
   8  *      modify it under the terms of the GNU General Public License
   9  *      as published by the Free Software Foundation; either version
  10  *      2 of the License, or (at your option) any later version.
  11  */
  12
  13 #ifndef _LINUX_IPSEC_H
  14 #define _LINUX_IPSEC_H
  15
  16 #include <linux/config.h>
  17 #include <linux/socket.h>
  18 #include <net/sock.h>
  19 #include <linux/skbuff.h>
  20
  21 /* Values for the set/getsockopt calls */
  22
  23 /* These defines are compatible with NRL IPv6, however their semantics
  24    is different */
  25
  26 #define IPSEC_LEVEL_NONE        -1      /* send plaintext, accept any */
  27 #define IPSEC_LEVEL_DEFAULT     0       /* encrypt/authenticate if possible */
  28                                         /* the default MUST be 0, because a */
  29                                         /* socket is initialized with 0's */
  30 #define IPSEC_LEVEL_USE         1       /* use outbound, don't require inbound */
  31 #define IPSEC_LEVEL_REQUIRE     2       /* require both directions */
  32 #define IPSEC_LEVEL_UNIQUE      2       /* for compatibility only */
  33
  34 #ifdef __KERNEL__
  35
  36 /* skb bit flags set on packet input processing */
  37
  38 #define RCV_SEC                 0x0f    /* options on receive */
  39 #define RCV_AUTH                0x01    /* was authenticated */
  40 #define RCV_CRYPT               0x02    /* was encrypted */
  41 #define RCV_TUNNEL              0x04    /* was tunneled */
  42 #define SND_SEC                 0xf0    /* options on send, these are */
  43 #define SND_AUTH                0x10    /* currently unused */
  44 #define SND_CRYPT               0x20
  45 #define SND_TUNNEL              0x40
  46
  47 /*
  48  *      FIXME: ignores network encryption for now..
  49  */
  50
  51 #ifdef CONFIG_NET_SECURITY
  52 extern __inline__ int ipsec_sk_policy(struct sock *sk, struct sk_buff *skb)
  53 {
  54         return ((sk->authentication < IPSEC_LEVEL_REQUIRE) ||
  55                 (skb->security & RCV_AUTH)) &&
  56                 ((sk->encryption < IPSEC_LEVEL_REQUIRE) ||
  57                 (skb->security & RCV_CRYPT));
  58 }
  59
  60 #else
  61
  62 extern __inline__ int ipsec_sk_policy(struct sock *sk, struct sk_buff *skb)
  63 {
  64         return 1;
  65 }
  66 #endif /* CONFIG */
  67
  68 #endif  /* __KERNEL__ */
  69 #endif  /* _LINUX_IPSEC_H */