2005-04-17 06:20:36 +08:00
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/* PF_KEY user interface, this is defined by rfc2367 so
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* do not make arbitrary modifications or else this header
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* file will not be compliant.
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*/
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#ifndef _LINUX_PFKEY2_H
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#define _LINUX_PFKEY2_H
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#include <linux/types.h>
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#define PF_KEY_V2 2
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#define PFKEYV2_REVISION 199806L
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struct sadb_msg {
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uint8_t sadb_msg_version;
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uint8_t sadb_msg_type;
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uint8_t sadb_msg_errno;
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uint8_t sadb_msg_satype;
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uint16_t sadb_msg_len;
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uint16_t sadb_msg_reserved;
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uint32_t sadb_msg_seq;
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uint32_t sadb_msg_pid;
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} __attribute__((packed));
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/* sizeof(struct sadb_msg) == 16 */
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struct sadb_ext {
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uint16_t sadb_ext_len;
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uint16_t sadb_ext_type;
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} __attribute__((packed));
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/* sizeof(struct sadb_ext) == 4 */
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struct sadb_sa {
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uint16_t sadb_sa_len;
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uint16_t sadb_sa_exttype;
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uint32_t sadb_sa_spi;
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uint8_t sadb_sa_replay;
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uint8_t sadb_sa_state;
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uint8_t sadb_sa_auth;
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uint8_t sadb_sa_encrypt;
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uint32_t sadb_sa_flags;
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} __attribute__((packed));
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/* sizeof(struct sadb_sa) == 16 */
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struct sadb_lifetime {
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uint16_t sadb_lifetime_len;
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uint16_t sadb_lifetime_exttype;
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uint32_t sadb_lifetime_allocations;
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uint64_t sadb_lifetime_bytes;
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uint64_t sadb_lifetime_addtime;
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uint64_t sadb_lifetime_usetime;
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} __attribute__((packed));
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/* sizeof(struct sadb_lifetime) == 32 */
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struct sadb_address {
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uint16_t sadb_address_len;
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uint16_t sadb_address_exttype;
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uint8_t sadb_address_proto;
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uint8_t sadb_address_prefixlen;
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uint16_t sadb_address_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_address) == 8 */
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struct sadb_key {
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uint16_t sadb_key_len;
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uint16_t sadb_key_exttype;
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uint16_t sadb_key_bits;
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uint16_t sadb_key_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_key) == 8 */
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struct sadb_ident {
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uint16_t sadb_ident_len;
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uint16_t sadb_ident_exttype;
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uint16_t sadb_ident_type;
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uint16_t sadb_ident_reserved;
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uint64_t sadb_ident_id;
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} __attribute__((packed));
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/* sizeof(struct sadb_ident) == 16 */
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struct sadb_sens {
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uint16_t sadb_sens_len;
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uint16_t sadb_sens_exttype;
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uint32_t sadb_sens_dpd;
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uint8_t sadb_sens_sens_level;
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uint8_t sadb_sens_sens_len;
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uint8_t sadb_sens_integ_level;
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uint8_t sadb_sens_integ_len;
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uint32_t sadb_sens_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_sens) == 16 */
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/* followed by:
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uint64_t sadb_sens_bitmap[sens_len];
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uint64_t sadb_integ_bitmap[integ_len]; */
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struct sadb_prop {
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uint16_t sadb_prop_len;
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uint16_t sadb_prop_exttype;
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uint8_t sadb_prop_replay;
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uint8_t sadb_prop_reserved[3];
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} __attribute__((packed));
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/* sizeof(struct sadb_prop) == 8 */
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/* followed by:
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struct sadb_comb sadb_combs[(sadb_prop_len +
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sizeof(uint64_t) - sizeof(struct sadb_prop)) /
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sizeof(strut sadb_comb)]; */
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struct sadb_comb {
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uint8_t sadb_comb_auth;
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uint8_t sadb_comb_encrypt;
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uint16_t sadb_comb_flags;
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uint16_t sadb_comb_auth_minbits;
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uint16_t sadb_comb_auth_maxbits;
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uint16_t sadb_comb_encrypt_minbits;
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uint16_t sadb_comb_encrypt_maxbits;
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uint32_t sadb_comb_reserved;
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uint32_t sadb_comb_soft_allocations;
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uint32_t sadb_comb_hard_allocations;
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uint64_t sadb_comb_soft_bytes;
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uint64_t sadb_comb_hard_bytes;
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uint64_t sadb_comb_soft_addtime;
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uint64_t sadb_comb_hard_addtime;
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uint64_t sadb_comb_soft_usetime;
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uint64_t sadb_comb_hard_usetime;
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} __attribute__((packed));
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/* sizeof(struct sadb_comb) == 72 */
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struct sadb_supported {
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uint16_t sadb_supported_len;
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uint16_t sadb_supported_exttype;
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uint32_t sadb_supported_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_supported) == 8 */
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/* followed by:
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struct sadb_alg sadb_algs[(sadb_supported_len +
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sizeof(uint64_t) - sizeof(struct sadb_supported)) /
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sizeof(struct sadb_alg)]; */
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struct sadb_alg {
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uint8_t sadb_alg_id;
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uint8_t sadb_alg_ivlen;
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uint16_t sadb_alg_minbits;
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uint16_t sadb_alg_maxbits;
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uint16_t sadb_alg_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_alg) == 8 */
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struct sadb_spirange {
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uint16_t sadb_spirange_len;
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uint16_t sadb_spirange_exttype;
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uint32_t sadb_spirange_min;
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uint32_t sadb_spirange_max;
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uint32_t sadb_spirange_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_spirange) == 16 */
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struct sadb_x_kmprivate {
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uint16_t sadb_x_kmprivate_len;
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uint16_t sadb_x_kmprivate_exttype;
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u_int32_t sadb_x_kmprivate_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_x_kmprivate) == 8 */
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struct sadb_x_sa2 {
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uint16_t sadb_x_sa2_len;
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uint16_t sadb_x_sa2_exttype;
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uint8_t sadb_x_sa2_mode;
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uint8_t sadb_x_sa2_reserved1;
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uint16_t sadb_x_sa2_reserved2;
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uint32_t sadb_x_sa2_sequence;
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uint32_t sadb_x_sa2_reqid;
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} __attribute__((packed));
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/* sizeof(struct sadb_x_sa2) == 16 */
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struct sadb_x_policy {
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uint16_t sadb_x_policy_len;
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uint16_t sadb_x_policy_exttype;
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uint16_t sadb_x_policy_type;
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uint8_t sadb_x_policy_dir;
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uint8_t sadb_x_policy_reserved;
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uint32_t sadb_x_policy_id;
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uint32_t sadb_x_policy_priority;
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} __attribute__((packed));
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/* sizeof(struct sadb_x_policy) == 16 */
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struct sadb_x_ipsecrequest {
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uint16_t sadb_x_ipsecrequest_len;
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uint16_t sadb_x_ipsecrequest_proto;
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uint8_t sadb_x_ipsecrequest_mode;
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uint8_t sadb_x_ipsecrequest_level;
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uint16_t sadb_x_ipsecrequest_reserved1;
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uint32_t sadb_x_ipsecrequest_reqid;
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uint32_t sadb_x_ipsecrequest_reserved2;
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} __attribute__((packed));
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/* sizeof(struct sadb_x_ipsecrequest) == 16 */
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/* This defines the TYPE of Nat Traversal in use. Currently only one
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* type of NAT-T is supported, draft-ietf-ipsec-udp-encaps-06
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*/
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struct sadb_x_nat_t_type {
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uint16_t sadb_x_nat_t_type_len;
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uint16_t sadb_x_nat_t_type_exttype;
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uint8_t sadb_x_nat_t_type_type;
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uint8_t sadb_x_nat_t_type_reserved[3];
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} __attribute__((packed));
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/* sizeof(struct sadb_x_nat_t_type) == 8 */
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/* Pass a NAT Traversal port (Source or Dest port) */
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struct sadb_x_nat_t_port {
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uint16_t sadb_x_nat_t_port_len;
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uint16_t sadb_x_nat_t_port_exttype;
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uint16_t sadb_x_nat_t_port_port;
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uint16_t sadb_x_nat_t_port_reserved;
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} __attribute__((packed));
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/* sizeof(struct sadb_x_nat_t_port) == 8 */
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[LSM-IPSec]: Security association restriction.
This patch series implements per packet access control via the
extension of the Linux Security Modules (LSM) interface by hooks in
the XFRM and pfkey subsystems that leverage IPSec security
associations to label packets. Extensions to the SELinux LSM are
included that leverage the patch for this purpose.
This patch implements the changes necessary to the XFRM subsystem,
pfkey interface, ipv4/ipv6, and xfrm_user interface to restrict a
socket to use only authorized security associations (or no security
association) to send/receive network packets.
Patch purpose:
The patch is designed to enable access control per packets based on
the strongly authenticated IPSec security association. Such access
controls augment the existing ones based on network interface and IP
address. The former are very coarse-grained, and the latter can be
spoofed. By using IPSec, the system can control access to remote
hosts based on cryptographic keys generated using the IPSec mechanism.
This enables access control on a per-machine basis or per-application
if the remote machine is running the same mechanism and trusted to
enforce the access control policy.
Patch design approach:
The overall approach is that policy (xfrm_policy) entries set by
user-level programs (e.g., setkey for ipsec-tools) are extended with a
security context that is used at policy selection time in the XFRM
subsystem to restrict the sockets that can send/receive packets via
security associations (xfrm_states) that are built from those
policies.
A presentation available at
www.selinux-symposium.org/2005/presentations/session2/2-3-jaeger.pdf
from the SELinux symposium describes the overall approach.
Patch implementation details:
On output, the policy retrieved (via xfrm_policy_lookup or
xfrm_sk_policy_lookup) must be authorized for the security context of
the socket and the same security context is required for resultant
security association (retrieved or negotiated via racoon in
ipsec-tools). This is enforced in xfrm_state_find.
On input, the policy retrieved must also be authorized for the socket
(at __xfrm_policy_check), and the security context of the policy must
also match the security association being used.
The patch has virtually no impact on packets that do not use IPSec.
The existing Netfilter (outgoing) and LSM rcv_skb hooks are used as
before.
Also, if IPSec is used without security contexts, the impact is
minimal. The LSM must allow such policies to be selected for the
combination of socket and remote machine, but subsequent IPSec
processing proceeds as in the original case.
Testing:
The pfkey interface is tested using the ipsec-tools. ipsec-tools have
been modified (a separate ipsec-tools patch is available for version
0.5) that supports assignment of xfrm_policy entries and security
associations with security contexts via setkey and the negotiation
using the security contexts via racoon.
The xfrm_user interface is tested via ad hoc programs that set
security contexts. These programs are also available from me, and
contain programs for setting, getting, and deleting policy for testing
this interface. Testing of sa functions was done by tracing kernel
behavior.
Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-14 15:12:27 +08:00
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/* Generic LSM security context */
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struct sadb_x_sec_ctx {
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uint16_t sadb_x_sec_len;
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uint16_t sadb_x_sec_exttype;
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uint8_t sadb_x_ctx_alg; /* LSMs: e.g., selinux == 1 */
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uint8_t sadb_x_ctx_doi;
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uint16_t sadb_x_ctx_len;
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} __attribute__((packed));
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/* sizeof(struct sadb_sec_ctx) = 8 */
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2005-04-17 06:20:36 +08:00
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/* Message types */
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#define SADB_RESERVED 0
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#define SADB_GETSPI 1
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#define SADB_UPDATE 2
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#define SADB_ADD 3
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#define SADB_DELETE 4
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#define SADB_GET 5
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#define SADB_ACQUIRE 6
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#define SADB_REGISTER 7
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#define SADB_EXPIRE 8
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#define SADB_FLUSH 9
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#define SADB_DUMP 10
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#define SADB_X_PROMISC 11
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#define SADB_X_PCHANGE 12
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#define SADB_X_SPDUPDATE 13
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#define SADB_X_SPDADD 14
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#define SADB_X_SPDDELETE 15
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#define SADB_X_SPDGET 16
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#define SADB_X_SPDACQUIRE 17
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#define SADB_X_SPDDUMP 18
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#define SADB_X_SPDFLUSH 19
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#define SADB_X_SPDSETIDX 20
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#define SADB_X_SPDEXPIRE 21
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#define SADB_X_SPDDELETE2 22
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#define SADB_X_NAT_T_NEW_MAPPING 23
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#define SADB_MAX 23
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/* Security Association flags */
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#define SADB_SAFLAGS_PFS 1
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2005-06-21 04:21:43 +08:00
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#define SADB_SAFLAGS_NOPMTUDISC 0x20000000
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2005-04-17 06:20:36 +08:00
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#define SADB_SAFLAGS_DECAP_DSCP 0x40000000
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#define SADB_SAFLAGS_NOECN 0x80000000
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/* Security Association states */
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#define SADB_SASTATE_LARVAL 0
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#define SADB_SASTATE_MATURE 1
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#define SADB_SASTATE_DYING 2
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#define SADB_SASTATE_DEAD 3
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#define SADB_SASTATE_MAX 3
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/* Security Association types */
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#define SADB_SATYPE_UNSPEC 0
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#define SADB_SATYPE_AH 2
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#define SADB_SATYPE_ESP 3
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#define SADB_SATYPE_RSVP 5
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#define SADB_SATYPE_OSPFV2 6
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#define SADB_SATYPE_RIPV2 7
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#define SADB_SATYPE_MIP 8
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#define SADB_X_SATYPE_IPCOMP 9
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#define SADB_SATYPE_MAX 9
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/* Authentication algorithms */
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#define SADB_AALG_NONE 0
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#define SADB_AALG_MD5HMAC 2
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#define SADB_AALG_SHA1HMAC 3
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#define SADB_X_AALG_SHA2_256HMAC 5
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#define SADB_X_AALG_SHA2_384HMAC 6
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#define SADB_X_AALG_SHA2_512HMAC 7
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#define SADB_X_AALG_RIPEMD160HMAC 8
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#define SADB_X_AALG_NULL 251 /* kame */
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#define SADB_AALG_MAX 251
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/* Encryption algorithms */
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#define SADB_EALG_NONE 0
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#define SADB_EALG_DESCBC 2
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#define SADB_EALG_3DESCBC 3
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#define SADB_X_EALG_CASTCBC 6
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#define SADB_X_EALG_BLOWFISHCBC 7
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#define SADB_EALG_NULL 11
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#define SADB_X_EALG_AESCBC 12
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#define SADB_EALG_MAX 253 /* last EALG */
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/* private allocations should use 249-255 (RFC2407) */
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#define SADB_X_EALG_SERPENTCBC 252 /* draft-ietf-ipsec-ciph-aes-cbc-00 */
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#define SADB_X_EALG_TWOFISHCBC 253 /* draft-ietf-ipsec-ciph-aes-cbc-00 */
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/* Compression algorithms */
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#define SADB_X_CALG_NONE 0
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#define SADB_X_CALG_OUI 1
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#define SADB_X_CALG_DEFLATE 2
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#define SADB_X_CALG_LZS 3
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#define SADB_X_CALG_LZJH 4
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#define SADB_X_CALG_MAX 4
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/* Extension Header values */
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#define SADB_EXT_RESERVED 0
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#define SADB_EXT_SA 1
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#define SADB_EXT_LIFETIME_CURRENT 2
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#define SADB_EXT_LIFETIME_HARD 3
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#define SADB_EXT_LIFETIME_SOFT 4
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#define SADB_EXT_ADDRESS_SRC 5
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#define SADB_EXT_ADDRESS_DST 6
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#define SADB_EXT_ADDRESS_PROXY 7
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#define SADB_EXT_KEY_AUTH 8
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#define SADB_EXT_KEY_ENCRYPT 9
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#define SADB_EXT_IDENTITY_SRC 10
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#define SADB_EXT_IDENTITY_DST 11
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#define SADB_EXT_SENSITIVITY 12
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#define SADB_EXT_PROPOSAL 13
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#define SADB_EXT_SUPPORTED_AUTH 14
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#define SADB_EXT_SUPPORTED_ENCRYPT 15
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#define SADB_EXT_SPIRANGE 16
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#define SADB_X_EXT_KMPRIVATE 17
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#define SADB_X_EXT_POLICY 18
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#define SADB_X_EXT_SA2 19
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/* The next four entries are for setting up NAT Traversal */
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#define SADB_X_EXT_NAT_T_TYPE 20
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#define SADB_X_EXT_NAT_T_SPORT 21
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#define SADB_X_EXT_NAT_T_DPORT 22
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#define SADB_X_EXT_NAT_T_OA 23
|
[LSM-IPSec]: Security association restriction.
This patch series implements per packet access control via the
extension of the Linux Security Modules (LSM) interface by hooks in
the XFRM and pfkey subsystems that leverage IPSec security
associations to label packets. Extensions to the SELinux LSM are
included that leverage the patch for this purpose.
This patch implements the changes necessary to the XFRM subsystem,
pfkey interface, ipv4/ipv6, and xfrm_user interface to restrict a
socket to use only authorized security associations (or no security
association) to send/receive network packets.
Patch purpose:
The patch is designed to enable access control per packets based on
the strongly authenticated IPSec security association. Such access
controls augment the existing ones based on network interface and IP
address. The former are very coarse-grained, and the latter can be
spoofed. By using IPSec, the system can control access to remote
hosts based on cryptographic keys generated using the IPSec mechanism.
This enables access control on a per-machine basis or per-application
if the remote machine is running the same mechanism and trusted to
enforce the access control policy.
Patch design approach:
The overall approach is that policy (xfrm_policy) entries set by
user-level programs (e.g., setkey for ipsec-tools) are extended with a
security context that is used at policy selection time in the XFRM
subsystem to restrict the sockets that can send/receive packets via
security associations (xfrm_states) that are built from those
policies.
A presentation available at
www.selinux-symposium.org/2005/presentations/session2/2-3-jaeger.pdf
from the SELinux symposium describes the overall approach.
Patch implementation details:
On output, the policy retrieved (via xfrm_policy_lookup or
xfrm_sk_policy_lookup) must be authorized for the security context of
the socket and the same security context is required for resultant
security association (retrieved or negotiated via racoon in
ipsec-tools). This is enforced in xfrm_state_find.
On input, the policy retrieved must also be authorized for the socket
(at __xfrm_policy_check), and the security context of the policy must
also match the security association being used.
The patch has virtually no impact on packets that do not use IPSec.
The existing Netfilter (outgoing) and LSM rcv_skb hooks are used as
before.
Also, if IPSec is used without security contexts, the impact is
minimal. The LSM must allow such policies to be selected for the
combination of socket and remote machine, but subsequent IPSec
processing proceeds as in the original case.
Testing:
The pfkey interface is tested using the ipsec-tools. ipsec-tools have
been modified (a separate ipsec-tools patch is available for version
0.5) that supports assignment of xfrm_policy entries and security
associations with security contexts via setkey and the negotiation
using the security contexts via racoon.
The xfrm_user interface is tested via ad hoc programs that set
security contexts. These programs are also available from me, and
contain programs for setting, getting, and deleting policy for testing
this interface. Testing of sa functions was done by tracing kernel
behavior.
Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-14 15:12:27 +08:00
|
|
|
#define SADB_X_EXT_SEC_CTX 24
|
|
|
|
|
#define SADB_EXT_MAX 24
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
|
/* Identity Extension values */
|
|
|
|
|
#define SADB_IDENTTYPE_RESERVED 0
|
|
|
|
|
#define SADB_IDENTTYPE_PREFIX 1
|
|
|
|
|
#define SADB_IDENTTYPE_FQDN 2
|
|
|
|
|
#define SADB_IDENTTYPE_USERFQDN 3
|
|
|
|
|
#define SADB_IDENTTYPE_MAX 3
|
|
|
|
|
|
|
|
|
|
#endif /* !(_LINUX_PFKEY2_H) */
|