ipv6.h

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#ifndef _IPXE_IPV6_H
#define _IPXE_IPV6_H

/** @file
 *
 * IPv6 protocol
 *
 */

FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );

#include <stdint.h>
#include <string.h>
#include <byteswap.h>
#include <ipxe/in.h>
#include <ipxe/list.h>
#include <ipxe/netdevice.h>

/** IPv6 version */
#define IPV6_VER 0x60000000UL

/** IPv6 version mask */
#define IPV6_MASK_VER 0xf0000000UL

/** IPv6 maximum hop limit */
#define IPV6_HOP_LIMIT 0xff

/** IPv6 default prefix length */
#define IPV6_DEFAULT_PREFIX_LEN 64

/** IPv6 maximum prefix length */
#define IPV6_MAX_PREFIX_LEN 128

/** IPv6 header */
struct ipv6_header {
        /** Version (4 bits), Traffic class (8 bits), Flow label (20 bits) */
        uint32_t ver_tc_label;
        /** Payload length, including any extension headers */
        uint16_t len;
        /** Next header type */
        uint8_t next_header;
        /** Hop limit */
        uint8_t hop_limit;
        /** Source address */
        struct in6_addr src;
        /** Destination address */
        struct in6_addr dest;
} __attribute__ (( packed ));

/** IPv6 extension header common fields */
struct ipv6_extension_header_common {
        /** Next header type */
        uint8_t next_header;
        /** Header extension length (excluding first 8 bytes) */
        uint8_t len;
} __attribute__ (( packed ));

/** IPv6 type-length-value options */
struct ipv6_option {
        /** Type */
        uint8_t type;
        /** Length */
        uint8_t len;
        /** Value */
        uint8_t value[0];
} __attribute__ (( packed ));

/** IPv6 option types */
enum ipv6_option_type {
        /** Pad1 */
        IPV6_OPT_PAD1 = 0x00,
        /** PadN */
        IPV6_OPT_PADN = 0x01,
};

/** Test if IPv6 option can be safely ignored */
#define IPV6_CAN_IGNORE_OPT( type ) ( ( (type) & 0xc0 ) == 0x00 )

/** IPv6 option-based extension header */
struct ipv6_options_header {
        /** Extension header common fields */
        struct ipv6_extension_header_common common;
        /** Options */
        struct ipv6_option options[0];
} __attribute__ (( packed ));

/** IPv6 routing header */
struct ipv6_routing_header {
        /** Extension header common fields */
        struct ipv6_extension_header_common common;
        /** Routing type */
        uint8_t type;
        /** Segments left */
        uint8_t remaining;
        /** Type-specific data */
        uint8_t data[0];
} __attribute__ (( packed ));

/** IPv6 fragment header */
struct ipv6_fragment_header {
        /** Extension header common fields */
        struct ipv6_extension_header_common common;
        /** Fragment offset (13 bits), reserved, more fragments (1 bit) */
        uint16_t offset_more;
        /** Identification */
        uint32_t ident;
} __attribute__ (( packed ));

/** Fragment offset mask */
#define IPV6_MASK_OFFSET 0xfff8

/** More fragments */
#define IPV6_MASK_MOREFRAGS 0x0001

/** IPv6 extension header */
union ipv6_extension_header {
        /** Extension header common fields */
        struct ipv6_extension_header_common common;
        /** Minimum size padding */
        uint8_t pad[8];
        /** Generic options header */
        struct ipv6_options_header options;
        /** Hop-by-hop options header */
        struct ipv6_options_header hopbyhop;
        /** Routing header */
        struct ipv6_routing_header routing;
        /** Fragment header */
        struct ipv6_fragment_header fragment;
        /** Destination options header */
        struct ipv6_options_header destination;
};

/** IPv6 header types */
enum ipv6_header_type {
        /** IPv6 hop-by-hop options header type */
        IPV6_HOPBYHOP = 0,
        /** IPv6 routing header type */
        IPV6_ROUTING = 43,
        /** IPv6 fragment header type */
        IPV6_FRAGMENT = 44,
        /** IPv6 no next header type */
        IPV6_NO_HEADER = 59,
        /** IPv6 destination options header type */
        IPV6_DESTINATION = 60,
};

/** IPv6 pseudo-header */
struct ipv6_pseudo_header {
        /** Source address */
        struct in6_addr src;
        /** Destination address */
        struct in6_addr dest;
        /** Upper-layer packet length */
        uint32_t len;
        /** Zero padding */
        uint8_t zero[3];
        /** Next header */
        uint8_t next_header;
} __attribute__ (( packed ));

/** IPv6 address scopes */
enum ipv6_address_scope {
        /** Interface-local address scope */
        IPV6_SCOPE_INTERFACE_LOCAL = 0x1,
        /** Link-local address scope */
        IPV6_SCOPE_LINK_LOCAL = 0x2,
        /** Admin-local address scope */
        INV6_SCOPE_ADMIN_LOCAL = 0x4,
        /** Site-local address scope */
        IPV6_SCOPE_SITE_LOCAL = 0x5,
        /** Organisation-local address scope */
        IPV6_SCOPE_ORGANISATION_LOCAL = 0x8,
        /** Global address scope */
        IPV6_SCOPE_GLOBAL = 0xe,
        /** Maximum scope */
        IPV6_SCOPE_MAX = 0xf,
};

/** An IPv6 address/routing table entry */
struct ipv6_miniroute {
        /** List of miniroutes */
        struct list_head list;

        /** Network device */
        struct net_device *netdev;

        /** IPv6 address (or prefix if no address is defined) */
        struct in6_addr address;
        /** Prefix length */
        unsigned int prefix_len;
        /** IPv6 prefix mask (derived from prefix length) */
        struct in6_addr prefix_mask;
        /** Router address */
        struct in6_addr router;
        /** Scope */
        unsigned int scope;
        /** Flags */
        unsigned int flags;
};

/** IPv6 address/routing table entry flags */
enum ipv6_miniroute_flags {
        /** Routing table entry address is valid */
        IPV6_HAS_ADDRESS = 0x0001,
        /** Routing table entry router address is valid */
        IPV6_HAS_ROUTER = 0x0002,
};

/**
 * Construct local IPv6 address via EUI-64
 *
 * @v addr              Prefix to be completed
 * @v netdev            Network device
 * @ret prefix_len      Prefix length, or negative error
 */
static inline int ipv6_eui64 ( struct in6_addr *addr,
                               struct net_device *netdev ) {
        struct ll_protocol *ll_protocol = netdev->ll_protocol;
        const void *ll_addr = netdev->ll_addr;
        int rc;

        if ( ( rc = ll_protocol->eui64 ( ll_addr, &addr->s6_addr[8] ) ) != 0 )
                return rc;
        addr->s6_addr[8] ^= 0x02;
        return 64;
}

/**
 * Construct link-local address via EUI-64
 *
 * @v addr              Zeroed address to construct
 * @v netdev            Network device
 * @ret prefix_len      Prefix length, or negative error
 */
static inline int ipv6_link_local ( struct in6_addr *addr,
                                    struct net_device *netdev ) {

        addr->s6_addr16[0] = htons ( 0xfe80 );
        return ipv6_eui64 ( addr, netdev );
}

/**
 * Construct solicited-node multicast address
 *
 * @v addr              Zeroed address to construct
 * @v unicast           Unicast address
 */
static inline void ipv6_solicited_node ( struct in6_addr *addr,
                                         const struct in6_addr *unicast ) {

        addr->s6_addr16[0] = htons ( 0xff02 );
        addr->s6_addr[11] = 1;
        addr->s6_addr[12] = 0xff;
        memcpy ( &addr->s6_addr[13], &unicast->s6_addr[13], 3 );
}

/**
 * Construct all-routers multicast address
 *
 * @v addr              Zeroed address to construct
 */
static inline void ipv6_all_routers ( struct in6_addr *addr ) {
        addr->s6_addr16[0] = htons ( 0xff02 );
        addr->s6_addr[15] = 2;
}

/**
 * Get multicast address scope
 *
 * @v addr              Multicast address
 * @ret scope           Address scope
 */
static inline unsigned int
ipv6_multicast_scope ( const struct in6_addr *addr ) {

        return ( addr->s6_addr[1] & 0x0f );
}

/** IPv6 settings sibling order */
enum ipv6_settings_order {
        /** No address */
        IPV6_ORDER_PREFIX_ONLY = -4,
        /** Link-local address */
        IPV6_ORDER_LINK_LOCAL = -3,
        /** Address assigned via SLAAC */
        IPV6_ORDER_SLAAC = -2,
        /** Address assigned via DHCPv6 */
        IPV6_ORDER_DHCPV6 = -1,
};

/** IPv6 link-local address settings block name */
#define IPV6_SETTINGS_NAME "link"

extern struct list_head ipv6_miniroutes;

extern struct net_protocol ipv6_protocol __net_protocol;

extern int ipv6_has_addr ( struct net_device *netdev, struct in6_addr *addr );
extern int ipv6_add_miniroute ( struct net_device *netdev,
                                struct in6_addr *address,
                                unsigned int prefix_len,
                                struct in6_addr *router );
extern void ipv6_del_miniroute ( struct ipv6_miniroute *miniroute );
extern struct ipv6_miniroute * ipv6_route ( unsigned int scope_id,
                                            struct in6_addr **dest );
extern int parse_ipv6_setting ( const struct setting_type *type,
                                const char *value, void *buf, size_t len );
extern int format_ipv6_setting ( const struct setting_type *type,
                                 const void *raw, size_t raw_len, char *buf,
                                 size_t len );

#endif /* _IPXE_IPV6_H */