/*      $OpenBSD: dhcp6leased.h,v 1.10 2025/09/18 11:49:23 florian Exp $        */

/*
 * Copyright (c) 2017, 2021 Florian Obser <florian@openbsd.org>
 * Copyright (c) 2004 Esben Norby <norby@openbsd.org>
 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef nitems
#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
#endif

#define _PATH_LOCKFILE          "/dev/dhcp6leased.lock"
#define _PATH_CONF_FILE         "/etc/dhcp6leased.conf"
#define _PATH_CTRL_SOCKET       "/dev/dhcp6leased.sock"
#define DHCP6LEASED_USER        "_dhcp6leased"
#define DHCP6LEASED_RTA_LABEL   "dhcp6leased"
#define CLIENT_PORT             546
#define SERVER_PORT             547
#define _PATH_LEASE             "/var/db/dhcp6leased/"
#define _PATH_UUID              _PATH_LEASE"uuid"
#define UUID_SIZE               16
#define UUID_STR_SIZE           sizeof("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX\n")
#define DUID_UUID_TYPE          4
#define XID_SIZE                3
#define SERVERID_SIZE           130 /* 2 octet type, max 128 octets data */
#define MAX_IA                  32
#define LEASE_SIZE              4096
#define LEASE_IA_PD_PREFIX      "ia_pd "
/* MAXDNAME from arpa/namesr.h */
#define DHCP6LEASED_MAX_DNSSL   1025
#define MAX_RDNS_COUNT          8 /* max nameserver in a RTM_PROPOSAL */

/* A 1500 bytes packet can hold less than 300 classless static routes */
#define MAX_DHCP_ROUTES         256

#define OPENBSD_ENTERPRISENO    30155

/* DHCP message types. */
#define DHCPSOLICIT             1
#define DHCPADVERTISE           2
#define DHCPREQUEST             3
#define DHCPCONFIRM             4
#define DHCPRENEW               5
#define DHCPREBIND              6
#define DHCPREPLY               7
#define DHCPRELEASE             8
#define DHCPDECLINE             9
#define DHCPRECONFIGURE         10
#define DHCPINFORMATIONREQUEST  11
#define DHCPRELAYFORW           12
#define DHCPRELAYREPL           13

/* DHCP options */
#define DHO_CLIENTID            1
#define DHO_SERVERID            2
#define DHO_ORO                 6
#define DHO_ELAPSED_TIME        8
#define DHO_STATUS_CODE         13
#define DHO_RAPID_COMMIT        14
#define DHO_VENDOR_CLASS        16
#define DHO_IA_PD               25
#define DHO_IA_PREFIX           26
#define DHO_SOL_MAX_RT          82
#define DHO_INF_MAX_RT          83

/* Status Code Option status codes */
#define DHCP_STATUS_SUCCESS             0
#define DHCP_STATUS_UNSPECFAIL          1
#define DHCP_STATUS_NOADDRSAVAIL        2
#define DHCP_STATUS_NOBINDING           3
#define DHCP_STATUS_NOTONLINK           4
#define DHCP_STATUS_USEMULTICAST        5
#define DHCP_STATUS_NOPREFIXAVAIL       6

/* Ignore parts of DHCP lease */
#define IGN_ROUTES      1
#define IGN_DNS         2

#define MAX_SERVERS     16      /* max servers that can be ignored per if */

#define IMSG_DATA_SIZE(imsg)    ((imsg).hdr.len - IMSG_HEADER_SIZE)
#define DHCP_SNAME_LEN          64
#define DHCP_FILE_LEN           128

struct dhcp_hdr {
        uint8_t         msg_type;       /* Message opcode/type */
        uint8_t         xid[XID_SIZE];  /* Transaction ID */
} __packed;

struct dhcp_option_hdr {
        uint16_t        code;
        uint16_t        len;
} __packed;

struct dhcp_duid {
        uint16_t        type;
        uint8_t         uuid[UUID_SIZE];
} __packed;

struct dhcp_iapd {
        uint32_t        iaid;
        uint32_t        t1;
        uint32_t        t2;
} __packed;

struct dhcp_vendor_class {
        uint32_t        enterprise_number;
        uint16_t        vendor_class_len;
} __packed;

struct dhcp_iaprefix {
        uint32_t        pltime;
        uint32_t        vltime;
        uint8_t         prefix_len;
        struct in6_addr prefix;
} __packed;

struct imsgev {
        struct imsgbuf   ibuf;
        void            (*handler)(int, short, void *);
        struct event     ev;
        short            events;
};

struct dhcp_route {
        struct in_addr           dst;
        struct in_addr           mask;
        struct in_addr           gw;
};

enum imsg_type {
        IMSG_NONE,
        IMSG_CTL_LOG_VERBOSE,
        IMSG_CTL_SHOW_INTERFACE_INFO,
        IMSG_CTL_SEND_REQUEST,
        IMSG_CTL_RELOAD,
        IMSG_CTL_END,
        IMSG_RECONF_CONF,
        IMSG_RECONF_IFACE,
        IMSG_RECONF_IFACE_IA,
        IMSG_RECONF_IFACE_PD,
        IMSG_RECONF_IFACE_IA_END,
        IMSG_RECONF_IFACE_END,
        IMSG_RECONF_END,
        IMSG_SEND_SOLICIT,
        IMSG_SEND_REQUEST,
        IMSG_SEND_RENEW,
        IMSG_SEND_REBIND,
        IMSG_SOCKET_IPC,
        IMSG_OPEN_UDPSOCK,
        IMSG_UDPSOCK,
        IMSG_ROUTESOCK,
        IMSG_UUID,
        IMSG_CONTROLFD,
        IMSG_STARTUP,
        IMSG_UPDATE_IF,
        IMSG_REMOVE_IF,
        IMSG_DHCP,
        IMSG_CONFIGURE_ADDRESS,
        IMSG_DECONFIGURE_ADDRESS,
        IMSG_CONFIGURE_REJECT_ROUTE,
        IMSG_DECONFIGURE_REJECT_ROUTE,
        IMSG_REQUEST_REBOOT,
        IMSG_WRITE_LEASE,
};

struct prefix {
        struct in6_addr  prefix;
        int              prefix_len;
        uint32_t         vltime;
        uint32_t         pltime;
};

struct ctl_engine_info {
        uint32_t                if_index;
        int                     running;
        int                     link_state;
        char                    state[sizeof("IF_INIT_REBOOT")];
        struct timespec         request_time;
        uint32_t                lease_time;
        uint32_t                t1;
        uint32_t                t2;
        struct prefix           pds[MAX_IA];
};

struct iface_pd_conf {
        SIMPLEQ_ENTRY(iface_pd_conf)     entry;
        char                             name[IF_NAMESIZE];
        struct in6_addr                  prefix_mask;
        int                              prefix_len;
};

struct iface_ia_conf {
        SIMPLEQ_ENTRY(iface_ia_conf)                     entry;
        SIMPLEQ_HEAD(iface_pd_conf_head, iface_pd_conf)  iface_pd_list;
        int                                              id;
        int                                              prefix_len;
};

struct iface_conf {
        SIMPLEQ_ENTRY(iface_conf)                entry;
        SIMPLEQ_HEAD(iface_ia_conf_head,
            iface_ia_conf)                       iface_ia_list;
        uint32_t                                 ia_count;
        char                                     name[IF_NAMESIZE];
};

struct dhcp6leased_conf {
        SIMPLEQ_HEAD(iface_conf_head, iface_conf)       iface_list;
        int                                             rapid_commit;
};

struct imsg_ifinfo {
        uint32_t                if_index;
        int                     rdomain;
        int                     running;
        int                     link_state;
        struct prefix           pds[MAX_IA];
};

struct imsg_dhcp {
        uint32_t                if_index;
        ssize_t                 len;
        uint8_t                 packet[1500];
};

struct imsg_req_dhcp {
        uint32_t                 if_index;
        int                      elapsed_time;
        uint8_t                  xid[XID_SIZE];
        int                      serverid_len;
        uint8_t                  serverid[SERVERID_SIZE];
        struct prefix            pds[MAX_IA];
};

struct imsg_lease_info {
        uint32_t                 if_index;
        struct prefix            pds[MAX_IA];
};

/* dhcp6leased.c */
void                     imsg_event_add(struct imsgev *);
int                      imsg_compose_event(struct imsgev *, uint16_t, uint32_t,
                             pid_t, int, void *, uint16_t);
void                     config_clear(struct dhcp6leased_conf *);
struct dhcp6leased_conf *config_new_empty(void);
void                     merge_config(struct dhcp6leased_conf *, struct
                             dhcp6leased_conf *);
const char              *sin6_to_str(struct sockaddr_in6 *);

/* engine.c */
const char              *dhcp_message_type2str(int);

/* frontend.c */
struct iface_conf       *find_iface_conf(struct iface_conf_head *, char *);
int                     *changed_ifaces(struct dhcp6leased_conf *, struct
                             dhcp6leased_conf *);
/* printconf.c */
void    print_config(struct dhcp6leased_conf *, int);

/* parse.y */
struct file {
        TAILQ_ENTRY(file)        entry;
        FILE                    *stream;
        char                    *name;
        size_t                   ungetpos;
        size_t                   ungetsize;
        u_char                  *ungetbuf;
        int                      eof_reached;
        int                      lineno;
        int                      errors;
};

struct dhcp6leased_conf *parse_config(const char *);
struct file             *pushfile(const char *, int);
int                      popfile(void);
int                      kw_cmp(const void *, const void *);
int                      lgetc(int);
void                     lungetc(int);
int                      findeol(void);

/* parse_lease.y */
void    parse_lease(const char*, struct imsg_ifinfo *);