[secnet] / secnet.h

/* Core interface of secnet, to be used by all modules */

#ifndef secnet_h
#define secnet_h

#include "config.h"
#include <stdlib.h>
#include <stdarg.h>
#include <stdio.h>
#include <sys/poll.h>
#include <sys/types.h>
#include <sys/time.h>
#include <netinet/in.h>

/*
 * Macros added by SGT for endianness-independence
 */
#define GET_32BIT_MSB_FIRST(cp) \
  (((unsigned long)(unsigned char)(cp)[0] << 24) | \
  ((unsigned long)(unsigned char)(cp)[1] << 16) | \
  ((unsigned long)(unsigned char)(cp)[2] << 8) | \
  ((unsigned long)(unsigned char)(cp)[3]))

#define PUT_32BIT_MSB_FIRST(cp, value) ( \
  (cp)[0] = (char)((value) >> 24), \
  (cp)[1] = (char)((value) >> 16), \
  (cp)[2] = (char)((value) >> 8), \
  (cp)[3] = (char)(value) )

typedef char *string_t;
typedef const char *cstring_t;
typedef enum {False,True} bool_t;

#define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
					 __FILE__,__LINE__); } } while(0)

/* from version.c */

extern char version[];

/* from logmsg.c */
extern uint32_t message_level;
extern bool_t secnet_is_daemon;
extern struct log_if *system_log;

/* from process.c */
extern void start_signal_handling(void);

/***** CONFIGURATION support *****/

extern bool_t just_check_config; /* If True then we're going to exit after
				    reading the configuration file */
extern bool_t background; /* If True then we'll eventually run as a daemon */

typedef struct dict dict_t;        /* Configuration dictionary */
typedef struct closure closure_t;
typedef struct item item_t;
typedef struct list list_t;        /* A list of items */

/* Configuration file location, for error-reporting */
struct cloc {
    cstring_t file;
    int line;
};

/* Modules export closures, which can be invoked from the configuration file.
   "Invoking" a closure usually returns another closure (of a different
   type), but can actually return any configuration object. */
typedef list_t *(apply_fn)(closure_t *self, struct cloc loc,
			   dict_t *context, list_t *data);
struct closure {
    cstring_t description; /* For debugging */
    uint32_t type; /* Central registry... */
    apply_fn *apply;
    void *interface; /* Interface for use inside secnet; depends on type */
};

enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
struct item {
    enum types type;
    union {
	bool_t bool;
	string_t string;
	uint32_t number;
	dict_t *dict;
	closure_t *closure;
    } data;
    struct cloc loc;
};

/* Note that it is unwise to use this structure directly; use the list
   manipulation functions instead. */
struct list {
    item_t *item;
    struct list *next;
};

/* In the following two lookup functions, NULL means 'not found' */
/* Lookup a value in the specified dictionary, or its parents */
extern list_t *dict_lookup(dict_t *dict, cstring_t key);
/* Lookup a value in just the specified dictionary */
extern list_t *dict_lookup_primitive(dict_t *dict, cstring_t key);
/* Add a value to the specified dictionary */
extern void dict_add(dict_t *dict, cstring_t key, list_t *val);
/* Obtain an array of keys in the dictionary. malloced; caller frees */
extern cstring_t *dict_keys(dict_t *dict);

/* List-manipulation functions */
extern list_t *list_new(void);
extern int32_t list_length(list_t *a);
extern list_t *list_append(list_t *a, item_t *i);
extern list_t *list_append_list(list_t *a, list_t *b);
/* Returns an item from the list (index starts at 0), or NULL */
extern item_t *list_elem(list_t *l, int32_t index);

/* Convenience functions */
extern list_t *new_closure(closure_t *cl);
extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
extern void *find_cl_if(dict_t *dict, cstring_t name, uint32_t type,
			bool_t fail_if_invalid, cstring_t desc,
			struct cloc loc);
extern item_t *dict_find_item(dict_t *dict, cstring_t key, bool_t required,
			      cstring_t desc, struct cloc loc);
extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
				 cstring_t desc, struct cloc loc);
extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
				 cstring_t desc, struct cloc loc,
				 uint32_t def);
  /* return value can safely be assigned to int32_t */
extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
			     cstring_t desc, struct cloc loc, bool_t def);
struct flagstr {
    cstring_t name;
    uint32_t value;
};
extern uint32_t string_to_word(cstring_t s, struct cloc loc,
			       struct flagstr *f, cstring_t desc);
extern uint32_t string_list_to_word(list_t *l, struct flagstr *f,
				    cstring_t desc);

/***** END of configuration support *****/

/***** UTILITY functions *****/

extern char *safe_strdup(const char *string, const char *message);
extern void *safe_malloc(size_t size, const char *message);
extern void *safe_malloc_ary(size_t size, size_t count, const char *message);

extern int sys_cmd(const char *file, const char *argc, ...);

extern uint64_t now_global;
extern struct timeval tv_now_global;

static const uint64_t       *const now    = &now_global;
static const struct timeval *const tv_now = &tv_now_global;

/* "now" is current program time, in milliseconds. It is derived
   from tv_now. Both are provided by the event loop. */

/***** END of utility functions *****/

/***** SCHEDULING support */

/* If nfds_io is insufficient for your needs, set it to the required
   number and return ERANGE. timeout is in milliseconds; if it is too
   high then lower it. It starts at -1 (==infinite) */
typedef int beforepoll_fn(void *st, struct pollfd *fds, int *nfds_io,
			  int *timeout_io);
typedef void afterpoll_fn(void *st, struct pollfd *fds, int nfds);

/* Register interest in the main loop of the program. Before a call
   to poll() your supplied beforepoll function will be called. After
   the call to poll() the supplied afterpoll function will be called.
   max_nfds is a _hint_ about the maximum number of struct pollfd
   structures you may require - you can always ask for more in
   *nfds_io. */
extern void register_for_poll(void *st, beforepoll_fn *before,
			      afterpoll_fn *after, int32_t max_nfds,
			      cstring_t desc);

/***** END of scheduling support */

/***** PROGRAM LIFETIME support */

/* The secnet program goes through a number of phases in its lifetime.
   Module code may arrange to be called just as various phases are
   entered.
 
   Remember to update the table in util.c if changing the set of
   phases. */

enum phase {
    PHASE_INIT,
    PHASE_GETOPTS,             /* Process command-line arguments */
    PHASE_READCONFIG,          /* Parse and process configuration file */
    PHASE_SETUP,               /* Process information in configuration */
    PHASE_DAEMONIZE,           /* Become a daemon (if necessary) */
    PHASE_GETRESOURCES,        /* Obtain all external resources */
    PHASE_DROPPRIV,            /* Last chance for privileged operations */
    PHASE_RUN,
    PHASE_SHUTDOWN,            /* About to die; delete key material, etc. */
    /* Keep this last: */
    NR_PHASES,
};

typedef void hook_fn(void *self, uint32_t newphase);
bool_t add_hook(uint32_t phase, hook_fn *f, void *state);
bool_t remove_hook(uint32_t phase, hook_fn *f, void *state);

extern uint32_t current_phase;
extern void enter_phase(uint32_t new_phase);

/* Some features (like netlink 'soft' routes) require that secnet
   retain root privileges.  They should indicate that here when
   appropriate. */
extern bool_t require_root_privileges;
extern cstring_t require_root_privileges_explanation;

/***** END of program lifetime support *****/

/***** MODULE support *****/

/* Module initialisation function type - modules export one function of
   this type which is called to initialise them. For dynamically loaded
   modules it's called "secnet_module". */
typedef void init_module(dict_t *dict);

extern void init_builtin_modules(dict_t *dict);

extern init_module resolver_module;
extern init_module random_module;
extern init_module udp_module;
extern init_module util_module;
extern init_module site_module;
extern init_module transform_module;
extern init_module netlink_module;
extern init_module rsa_module;
extern init_module dh_module;
extern init_module md5_module;
extern init_module slip_module;
extern init_module tun_module;
extern init_module sha1_module;
extern init_module log_module;

/***** END of module support *****/

/***** CLOSURE TYPES and interface definitions *****/

#define CL_PURE         0
#define CL_RESOLVER     1
#define CL_RANDOMSRC    2
#define CL_RSAPUBKEY    3
#define CL_RSAPRIVKEY   4
#define CL_COMM         5
#define CL_IPIF         6
#define CL_LOG          7
#define CL_SITE         8
#define CL_TRANSFORM    9
#define CL_DH          11
#define CL_HASH        12
#define CL_BUFFER      13
#define CL_NETLINK     14

struct buffer_if;

/* PURE closure requires no interface */

/* RESOLVER interface */

/* Answers to queries are delivered to a function of this
   type. 'address' will be NULL if there was a problem with the query. It
   will be freed once resolve_answer_fn returns. It is in network byte
   order. */
/* XXX extend to be able to provide multiple answers */
typedef void resolve_answer_fn(void *st, struct in_addr *addr);
typedef bool_t resolve_request_fn(void *st, cstring_t name,
				  resolve_answer_fn *cb, void *cst);
struct resolver_if {
    void *st;
    resolve_request_fn *request;
};

/* RANDOMSRC interface */

/* Return some random data. Returns TRUE for success. */
typedef bool_t random_fn(void *st, int32_t bytes, uint8_t *buff);

struct random_if {
    void *st;
    bool_t blocking;
    random_fn *generate;
};

/* RSAPUBKEY interface */

typedef bool_t rsa_checksig_fn(void *st, uint8_t *data, int32_t datalen,
			       cstring_t signature);
struct rsapubkey_if {
    void *st;
    rsa_checksig_fn *check;
};

/* RSAPRIVKEY interface */

typedef string_t rsa_makesig_fn(void *st, uint8_t *data, int32_t datalen);
struct rsaprivkey_if {
    void *st;
    rsa_makesig_fn *sign;
};

/* COMM interface */

struct comm_addr {
    /* This struct is pure data; in particular comm's clients may
       freely copy it. */
    /* Everyone is also guaranteed that all padding is set to zero, ie
       that comm_addrs referring to semantically identical peers will
       compare equal with memcmp.  Anyone who constructs a comm_addr
       must start by memsetting it with FILLZERO, or some
       equivalent. */
    struct comm_if *comm;
    struct sockaddr_in sin;
};

/* Return True if the packet was processed, and shouldn't be passed to
   any other potential receivers. */
typedef bool_t comm_notify_fn(void *state, struct buffer_if *buf,
			      const struct comm_addr *source);
typedef void comm_request_notify_fn(void *commst, void *nst,
				    comm_notify_fn *fn);
typedef void comm_release_notify_fn(void *commst, void *nst,
				    comm_notify_fn *fn);
typedef bool_t comm_sendmsg_fn(void *commst, struct buffer_if *buf,
			       const struct comm_addr *dest);
typedef const char *comm_addr_to_string_fn(void *commst,
					   const struct comm_addr *ca);
        /* Returned string is in a static buffer. */
struct comm_if {
    void *st;
    int32_t min_start_pad;
    int32_t min_end_pad;
    comm_request_notify_fn *request_notify;
    comm_release_notify_fn *release_notify;
    comm_sendmsg_fn *sendmsg;
    comm_addr_to_string_fn *addr_to_string;
};

/* LOG interface */

typedef void log_msg_fn(void *st, int class, const char *message, ...);
typedef void log_vmsg_fn(void *st, int class, const char *message,
			 va_list args);
struct log_if {
    void *st;
    log_msg_fn *log;
    log_vmsg_fn *vlog;
};
/* (convenience functions, defined in util.c) */
extern void slilog(struct log_if *lf, int class, const char *message, ...)
FORMAT(printf,3,4);
extern void vslilog(struct log_if *lf, int class, const char *message, va_list)
FORMAT(printf,3,0);

/* SITE interface */

/* Pretty much a placeholder; allows starting and stopping of processing,
   key expiry, etc. */
typedef void site_control_fn(void *st, bool_t run);
typedef uint32_t site_status_fn(void *st);
struct site_if {
    void *st;
    site_control_fn *control;
    site_status_fn *status;
};

/* TRANSFORM interface */

/* A reversable transformation. Transforms buffer in-place; may add
   data to start or end. Maximum amount of data to be added specified
   in max_start_pad and max_end_pad. (Reverse transformations decrease
   length, of course.)  Transformations may be key-dependent, in which
   case key material is passed in at initialisation time. They may
   also depend on internal factors (eg. time) and keep internal
   state. A struct transform_if only represents a particular type of
   transformation; instances of the transformation (eg. with
   particular key material) have a different C type. */

typedef struct transform_inst_if *transform_createinstance_fn(void *st);
typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen);
typedef void transform_delkey_fn(void *st);
typedef void transform_destroyinstance_fn(void *st);
/* Returns:
 *   0: all is well
 *   1: for any other problem
 *   2: message decrypted but sequence number was out of range
 */
typedef uint32_t transform_apply_fn(void *st, struct buffer_if *buf,
				    const char **errmsg);

struct transform_inst_if {
    void *st;
    transform_setkey_fn *setkey;
    transform_delkey_fn *delkey;
    transform_apply_fn *forwards;
    transform_apply_fn *reverse;
    transform_destroyinstance_fn *destroy;
};

struct transform_if {
    void *st;
    int32_t max_start_pad; /* these three are all <<< INT_MAX */
    int32_t max_end_pad;
    int32_t keylen;
    transform_createinstance_fn *create;
};

/* NETLINK interface */

/* Used by netlink to deliver to site, and by site to deliver to
   netlink.  cid is the client identifier returned by
   netlink_regnets_fn.  If buf has size 0 then the function is just
   being called for its site-effects (eg. making the site code attempt
   to bring up a network link) */
typedef void netlink_deliver_fn(void *st, struct buffer_if *buf);
/* site code can tell netlink when outgoing packets will be dropped,
   so netlink can generate appropriate ICMP and make routing decisions */
#define LINK_QUALITY_UNUSED 0   /* This link is unused, do not make this netlink */
#define LINK_QUALITY_DOWN 1   /* No chance of a packet being delivered right away*/
#define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
#define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
#define LINK_QUALITY_UP 4     /* Link active */
#define MAXIMUM_LINK_QUALITY 3
typedef void netlink_link_quality_fn(void *st, uint32_t quality);
typedef void netlink_register_fn(void *st, netlink_deliver_fn *deliver,
				 void *dst, int32_t max_start_pad,
				 int32_t max_end_pad);
typedef void netlink_output_config_fn(void *st, struct buffer_if *buf);
typedef bool_t netlink_check_config_fn(void *st, struct buffer_if *buf);
typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
struct netlink_if {
    void *st;
    netlink_register_fn *reg;
    netlink_deliver_fn *deliver;
    netlink_link_quality_fn *set_quality;
    netlink_set_mtu_fn *set_mtu;
};

/* DH interface */

/* Returns public key as a malloced hex string */
typedef string_t dh_makepublic_fn(void *st, uint8_t *secret,
				  int32_t secretlen);
/* Fills buffer (up to buflen) with shared secret */
typedef void dh_makeshared_fn(void *st, uint8_t *secret,
			      int32_t secretlen, cstring_t rempublic,
			      uint8_t *sharedsecret, int32_t buflen);
struct dh_if {
    void *st;
    int32_t len; /* Approximate size of modulus in bytes */
    dh_makepublic_fn *makepublic;
    dh_makeshared_fn *makeshared;
};

/* HASH interface */

typedef void *hash_init_fn(void);
typedef void hash_update_fn(void *st, const void *buf, int32_t len);
typedef void hash_final_fn(void *st, uint8_t *digest);
struct hash_if {
    int32_t len; /* Hash output length in bytes */
    hash_init_fn *init;
    hash_update_fn *update;
    hash_final_fn *final;
};

/* BUFFER interface */

struct buffer_if {
    bool_t free;
    cstring_t owner; /* Set to constant string */
    uint32_t flags; /* How paranoid should we be? */
    struct cloc loc; /* Where we were defined */
    uint8_t *base;
    uint8_t *start;
    int32_t size; /* Size of buffer contents */
    int32_t len; /* Total length allocated at base */
};

/***** LOG functions *****/

#define M_DEBUG_CONFIG 0x001
#define M_DEBUG_PHASE  0x002
#define M_DEBUG        0x004
#define M_INFO	       0x008
#define M_NOTICE       0x010
#define M_WARNING      0x020
#define M_ERR	       0x040
#define M_SECURITY     0x080
#define M_FATAL	       0x100

/* The fatal() family of functions require messages that do not end in '\n' */
extern NORETURN(fatal(const char *message, ...));
extern NORETURN(fatal_perror(const char *message, ...));
extern NORETURN(fatal_status(int status, const char *message, ...));
extern NORETURN(fatal_perror_status(int status, const char *message, ...));

/* The cfgfatal() family of functions require messages that end in '\n' */
extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
			 const char *message, ...));
extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
				    cstring_t facility, const char *message,
				    va_list));
extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
				   cstring_t facility,
				   const char *message, ...));

extern void Message(uint32_t class, const char *message, ...)
    FORMAT(printf,2,3);
extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);

/***** END of log functions *****/

#define STRING2(x) #x
#define STRING(x) STRING2(x)

#define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))

#endif /* secnet_h */
Commit	Line	Data
2fe58dfd SE	1	/* Core interface of secnet, to be used by all modules */
	2
	3	#ifndef secnet_h
	4	#define secnet_h
	5
59635212	6	#include "config.h"
2fe58dfd	7	#include <stdlib.h>
2fe58dfd	8	#include <stdarg.h>
4f5e39ec	9	#include <stdio.h>
2fe58dfd	10	#include <sys/poll.h>
8689b3a9 SE	11	#include <sys/types.h>
8689b3a9 SE	12	#include <sys/time.h>
2fe58dfd	13	#include <netinet/in.h>
2fe58dfd	14
3b83c932 SE	15	/*
	16	* Macros added by SGT for endianness-independence
	17	*/
	18	#define GET_32BIT_MSB_FIRST(cp) \
	19	(((unsigned long)(unsigned char)(cp)[0] << 24) \| \
	20	((unsigned long)(unsigned char)(cp)[1] << 16) \| \
	21	((unsigned long)(unsigned char)(cp)[2] << 8) \| \
	22	((unsigned long)(unsigned char)(cp)[3]))
	23
	24	#define PUT_32BIT_MSB_FIRST(cp, value) ( \
	25	(cp)[0] = (char)((value) >> 24), \
	26	(cp)[1] = (char)((value) >> 16), \
	27	(cp)[2] = (char)((value) >> 8), \
	28	(cp)[3] = (char)(value) )
	29
2fe58dfd	30	typedef char *string_t;
fe5e9cc4	31	typedef const char *cstring_t;
2fe58dfd SE	32	typedef enum {False,True} bool_t;
2fe58dfd SE	33
794f2398	34	#define ASSERT(x) do { if (!(x)) { fatal("assertion failed line %d file " \
4f5e39ec	35	__FILE__,__LINE__); } } while(0)
2fe58dfd	36
fcbc5905 IJ	37	/* from version.c */
	38
	39	extern char version[];
	40
08ee90a2 IJ	41	/* from logmsg.c */
	42	extern uint32_t message_level;
	43	extern bool_t secnet_is_daemon;
	44	extern struct log_if *system_log;
	45
	46	/* from process.c */
	47	extern void start_signal_handling(void);
	48
2fe58dfd SE	49	/*** CONFIGURATION support ***/
2fe58dfd SE	50
baa06aeb SE	51	extern bool_t just_check_config; /* If True then we're going to exit after
baa06aeb SE	52	reading the configuration file */
b2a56f7c	53	extern bool_t background; /* If True then we'll eventually run as a daemon */
baa06aeb	54
2fe58dfd SE	55	typedef struct dict dict_t; /* Configuration dictionary */
	56	typedef struct closure closure_t;
	57	typedef struct item item_t;
	58	typedef struct list list_t; /* A list of items */
	59
	60	/* Configuration file location, for error-reporting */
	61	struct cloc {
fe5e9cc4	62	cstring_t file;
1caa23ff	63	int line;
2fe58dfd SE	64	};
	65
	66	/* Modules export closures, which can be invoked from the configuration file.
	67	"Invoking" a closure usually returns another closure (of a different
	68	type), but can actually return any configuration object. */
	69	typedef list_t (apply_fn)(closure_t self, struct cloc loc,
	70	dict_t context, list_t data);
	71	struct closure {
fe5e9cc4	72	cstring_t description; /* For debugging */
2fe58dfd SE	73	uint32_t type; /* Central registry... */
	74	apply_fn *apply;
	75	void interface; / Interface for use inside secnet; depends on type */
	76	};
	77
	78	enum types { t_null, t_bool, t_string, t_number, t_dict, t_closure };
	79	struct item {
	80	enum types type;
	81	union {
	82	bool_t bool;
	83	string_t string;
	84	uint32_t number;
	85	dict_t *dict;
	86	closure_t *closure;
	87	} data;
	88	struct cloc loc;
	89	};
	90
ff05a229 SE	91	/* Note that it is unwise to use this structure directly; use the list
ff05a229 SE	92	manipulation functions instead. */
2fe58dfd SE	93	struct list {
	94	item_t *item;
	95	struct list *next;
	96	};
	97
	98	/* In the following two lookup functions, NULL means 'not found' */
	99	/* Lookup a value in the specified dictionary, or its parents */
fe5e9cc4	100	extern list_t dict_lookup(dict_t dict, cstring_t key);
2fe58dfd	101	/* Lookup a value in just the specified dictionary */
fe5e9cc4	102	extern list_t dict_lookup_primitive(dict_t dict, cstring_t key);
2fe58dfd	103	/* Add a value to the specified dictionary */
fe5e9cc4	104	extern void dict_add(dict_t dict, cstring_t key, list_t val);
2fe58dfd	105	/* Obtain an array of keys in the dictionary. malloced; caller frees */
fe5e9cc4	106	extern cstring_t dict_keys(dict_t dict);
2fe58dfd SE	107
	108	/* List-manipulation functions */
	109	extern list_t *list_new(void);
1caa23ff	110	extern int32_t list_length(list_t *a);
2fe58dfd SE	111	extern list_t list_append(list_t a, item_t *i);
	112	extern list_t list_append_list(list_t a, list_t *b);
	113	/* Returns an item from the list (index starts at 0), or NULL */
1caa23ff	114	extern item_t list_elem(list_t l, int32_t index);
2fe58dfd SE	115
	116	/* Convenience functions */
	117	extern list_t new_closure(closure_t cl);
fe5e9cc4 SE	118	extern void add_closure(dict_t *dict, cstring_t name, apply_fn apply);
	119	extern void find_cl_if(dict_t dict, cstring_t name, uint32_t type,
	120	bool_t fail_if_invalid, cstring_t desc,
2fe58dfd	121	struct cloc loc);
fe5e9cc4 SE	122	extern item_t dict_find_item(dict_t dict, cstring_t key, bool_t required,
	123	cstring_t desc, struct cloc loc);
	124	extern string_t dict_read_string(dict_t *dict, cstring_t key, bool_t required,
	125	cstring_t desc, struct cloc loc);
	126	extern uint32_t dict_read_number(dict_t *dict, cstring_t key, bool_t required,
	127	cstring_t desc, struct cloc loc,
	128	uint32_t def);
59230b9b	129	/* return value can safely be assigned to int32_t */
fe5e9cc4 SE	130	extern bool_t dict_read_bool(dict_t *dict, cstring_t key, bool_t required,
fe5e9cc4 SE	131	cstring_t desc, struct cloc loc, bool_t def);
9d3a4132	132	struct flagstr {
fe5e9cc4	133	cstring_t name;
9d3a4132 SE	134	uint32_t value;
9d3a4132 SE	135	};
fe5e9cc4 SE	136	extern uint32_t string_to_word(cstring_t s, struct cloc loc,
fe5e9cc4 SE	137	struct flagstr *f, cstring_t desc);
9d3a4132	138	extern uint32_t string_list_to_word(list_t l, struct flagstr f,
fe5e9cc4	139	cstring_t desc);
2fe58dfd SE	140
	141	/*** END of configuration support ***/
	142
7138d0c5 SE	143	/*** UTILITY functions ***/
7138d0c5 SE	144
fe5e9cc4 SE	145	extern char safe_strdup(const char string, const char *message);
fe5e9cc4 SE	146	extern void safe_malloc(size_t size, const char message);
bb9d0561	147	extern void safe_malloc_ary(size_t size, size_t count, const char message);
2fe58dfd	148
fe5e9cc4	149	extern int sys_cmd(const char file, const char argc, ...);
4efd681a	150
698280de IJ	151	extern uint64_t now_global;
	152	extern struct timeval tv_now_global;
	153
	154	static const uint64_t *const now = &now_global;
	155	static const struct timeval *const tv_now = &tv_now_global;
	156
	157	/* "now" is current program time, in milliseconds. It is derived
	158	from tv_now. Both are provided by the event loop. */
	159
2fe58dfd SE	160	/*** END of utility functions ***/
	161
	162	/***** SCHEDULING support */
	163
90a39563 IJ	164	/* If nfds_io is insufficient for your needs, set it to the required
	165	number and return ERANGE. timeout is in milliseconds; if it is too
	166	high then lower it. It starts at -1 (==infinite) */
2fe58dfd	167	typedef int beforepoll_fn(void st, struct pollfd fds, int *nfds_io,
90a39563 IJ	168	int *timeout_io);
90a39563 IJ	169	typedef void afterpoll_fn(void st, struct pollfd fds, int nfds);
2fe58dfd SE	170
	171	/* Register interest in the main loop of the program. Before a call
	172	to poll() your supplied beforepoll function will be called. After
	173	the call to poll() the supplied afterpoll function will be called.
	174	max_nfds is a _hint_ about the maximum number of struct pollfd
	175	structures you may require - you can always ask for more in
	176	nfds_io. /
	177	extern void register_for_poll(void st, beforepoll_fn before,
1caa23ff	178	afterpoll_fn *after, int32_t max_nfds,
fe5e9cc4	179	cstring_t desc);
2fe58dfd SE	180
	181	/***** END of scheduling support */
	182
	183	/***** PROGRAM LIFETIME support */
	184
	185	/* The secnet program goes through a number of phases in its lifetime.
	186	Module code may arrange to be called just as various phases are
7b1a9fb7 RK	187	entered.
	188
	189	Remember to update the table in util.c if changing the set of
	190	phases. */
2fe58dfd	191
42394c37 RK	192	enum phase {
	193	PHASE_INIT,
	194	PHASE_GETOPTS, /* Process command-line arguments */
	195	PHASE_READCONFIG, /* Parse and process configuration file */
	196	PHASE_SETUP, /* Process information in configuration */
7b1a9fb7	197	PHASE_DAEMONIZE, /* Become a daemon (if necessary) */
42394c37 RK	198	PHASE_GETRESOURCES, /* Obtain all external resources */
	199	PHASE_DROPPRIV, /* Last chance for privileged operations */
	200	PHASE_RUN,
	201	PHASE_SHUTDOWN, /* About to die; delete key material, etc. */
	202	/* Keep this last: */
	203	NR_PHASES,
	204	};
2fe58dfd SE	205
	206	typedef void hook_fn(void *self, uint32_t newphase);
	207	bool_t add_hook(uint32_t phase, hook_fn f, void state);
	208	bool_t remove_hook(uint32_t phase, hook_fn f, void state);
	209
7138d0c5 SE	210	extern uint32_t current_phase;
	211	extern void enter_phase(uint32_t new_phase);
	212
ff05a229 SE	213	/* Some features (like netlink 'soft' routes) require that secnet
	214	retain root privileges. They should indicate that here when
	215	appropriate. */
	216	extern bool_t require_root_privileges;
fe5e9cc4	217	extern cstring_t require_root_privileges_explanation;
9d3a4132	218
2fe58dfd SE	219	/*** END of program lifetime support ***/
	220
	221	/*** MODULE support ***/
	222
	223	/* Module initialisation function type - modules export one function of
	224	this type which is called to initialise them. For dynamically loaded
	225	modules it's called "secnet_module". */
469fd1d9	226	typedef void init_module(dict_t *dict);
2fe58dfd	227
08ee90a2 IJ	228	extern void init_builtin_modules(dict_t *dict);
	229
	230	extern init_module resolver_module;
	231	extern init_module random_module;
	232	extern init_module udp_module;
	233	extern init_module util_module;
	234	extern init_module site_module;
	235	extern init_module transform_module;
	236	extern init_module netlink_module;
	237	extern init_module rsa_module;
	238	extern init_module dh_module;
	239	extern init_module md5_module;
	240	extern init_module slip_module;
	241	extern init_module tun_module;
	242	extern init_module sha1_module;
	243	extern init_module log_module;
	244
2fe58dfd SE	245	/*** END of module support ***/
	246
	247	/*** CLOSURE TYPES and interface definitions ***/
	248
469fd1d9 SE	249	#define CL_PURE 0
	250	#define CL_RESOLVER 1
	251	#define CL_RANDOMSRC 2
	252	#define CL_RSAPUBKEY 3
	253	#define CL_RSAPRIVKEY 4
	254	#define CL_COMM 5
	255	#define CL_IPIF 6
	256	#define CL_LOG 7
	257	#define CL_SITE 8
	258	#define CL_TRANSFORM 9
	259	#define CL_DH 11
	260	#define CL_HASH 12
	261	#define CL_BUFFER 13
	262	#define CL_NETLINK 14
2fe58dfd SE	263
	264	struct buffer_if;
	265
	266	/* PURE closure requires no interface */
	267
	268	/* RESOLVER interface */
	269
	270	/* Answers to queries are delivered to a function of this
	271	type. 'address' will be NULL if there was a problem with the query. It
	272	will be freed once resolve_answer_fn returns. It is in network byte
	273	order. */
ff05a229	274	/* XXX extend to be able to provide multiple answers */
2fe58dfd	275	typedef void resolve_answer_fn(void st, struct in_addr addr);
fe5e9cc4	276	typedef bool_t resolve_request_fn(void *st, cstring_t name,
2fe58dfd SE	277	resolve_answer_fn cb, void cst);
	278	struct resolver_if {
	279	void *st;
	280	resolve_request_fn *request;
	281	};
	282
	283	/* RANDOMSRC interface */
	284
	285	/* Return some random data. Returns TRUE for success. */
1caa23ff	286	typedef bool_t random_fn(void st, int32_t bytes, uint8_t buff);
2fe58dfd SE	287
	288	struct random_if {
	289	void *st;
	290	bool_t blocking;
	291	random_fn *generate;
	292	};
	293
	294	/* RSAPUBKEY interface */
	295
1caa23ff	296	typedef bool_t rsa_checksig_fn(void st, uint8_t data, int32_t datalen,
fe5e9cc4	297	cstring_t signature);
2fe58dfd SE	298	struct rsapubkey_if {
	299	void *st;
	300	rsa_checksig_fn *check;
	301	};
	302
	303	/* RSAPRIVKEY interface */
	304
1caa23ff	305	typedef string_t rsa_makesig_fn(void st, uint8_t data, int32_t datalen);
2fe58dfd SE	306	struct rsaprivkey_if {
	307	void *st;
	308	rsa_makesig_fn *sign;
	309	};
	310
	311	/* COMM interface */
	312
a15faeb2 IJ	313	struct comm_addr {
	314	/* This struct is pure data; in particular comm's clients may
	315	freely copy it. */
	316	/* Everyone is also guaranteed that all padding is set to zero, ie
	317	that comm_addrs referring to semantically identical peers will
	318	compare equal with memcmp. Anyone who constructs a comm_addr
	319	must start by memsetting it with FILLZERO, or some
	320	equivalent. */
	321	struct comm_if *comm;
	322	struct sockaddr_in sin;
	323	};
	324
2fe58dfd SE	325	/* Return True if the packet was processed, and shouldn't be passed to
	326	any other potential receivers. */
	327	typedef bool_t comm_notify_fn(void state, struct buffer_if buf,
a15faeb2	328	const struct comm_addr *source);
2fe58dfd SE	329	typedef void comm_request_notify_fn(void commst, void nst,
	330	comm_notify_fn *fn);
	331	typedef void comm_release_notify_fn(void commst, void nst,
	332	comm_notify_fn *fn);
	333	typedef bool_t comm_sendmsg_fn(void commst, struct buffer_if buf,
a15faeb2	334	const struct comm_addr *dest);
5edf478f IJ	335	typedef const char comm_addr_to_string_fn(void commst,
	336	const struct comm_addr *ca);
	337	/* Returned string is in a static buffer. */
2fe58dfd SE	338	struct comm_if {
2fe58dfd SE	339	void *st;
1caa23ff IJ	340	int32_t min_start_pad;
1caa23ff IJ	341	int32_t min_end_pad;
2fe58dfd SE	342	comm_request_notify_fn *request_notify;
	343	comm_release_notify_fn *release_notify;
	344	comm_sendmsg_fn *sendmsg;
5edf478f	345	comm_addr_to_string_fn *addr_to_string;
2fe58dfd SE	346	};
	347
	348	/* LOG interface */
	349
fe5e9cc4 SE	350	typedef void log_msg_fn(void st, int class, const char message, ...);
	351	typedef void log_vmsg_fn(void st, int class, const char message,
	352	va_list args);
2fe58dfd SE	353	struct log_if {
	354	void *st;
	355	log_msg_fn *log;
	356	log_vmsg_fn *vlog;
	357	};
59938e0e	358	/* (convenience functions, defined in util.c) */
040ee979	359	extern void slilog(struct log_if lf, int class, const char message, ...)
4f5e39ec	360	FORMAT(printf,3,4);
59938e0e IJ	361	extern void vslilog(struct log_if lf, int class, const char message, va_list)
59938e0e IJ	362	FORMAT(printf,3,0);
2fe58dfd SE	363
	364	/* SITE interface */
	365
	366	/* Pretty much a placeholder; allows starting and stopping of processing,
	367	key expiry, etc. */
	368	typedef void site_control_fn(void *st, bool_t run);
	369	typedef uint32_t site_status_fn(void *st);
	370	struct site_if {
	371	void *st;
	372	site_control_fn *control;
	373	site_status_fn *status;
	374	};
	375
	376	/* TRANSFORM interface */
	377
	378	/* A reversable transformation. Transforms buffer in-place; may add
	379	data to start or end. Maximum amount of data to be added specified
	380	in max_start_pad and max_end_pad. (Reverse transformations decrease
	381	length, of course.) Transformations may be key-dependent, in which
	382	case key material is passed in at initialisation time. They may
	383	also depend on internal factors (eg. time) and keep internal
	384	state. A struct transform_if only represents a particular type of
	385	transformation; instances of the transformation (eg. with
	386	particular key material) have a different C type. */
	387
	388	typedef struct transform_inst_if transform_createinstance_fn(void st);
1caa23ff	389	typedef bool_t transform_setkey_fn(void st, uint8_t key, int32_t keylen);
2fe58dfd SE	390	typedef void transform_delkey_fn(void *st);
2fe58dfd SE	391	typedef void transform_destroyinstance_fn(void *st);
07e4774c IJ	392	/* Returns:
	393	* 0: all is well
	394	* 1: for any other problem
	395	* 2: message decrypted but sequence number was out of range
	396	*/
2fe58dfd	397	typedef uint32_t transform_apply_fn(void st, struct buffer_if buf,
fe5e9cc4	398	const char **errmsg);
2fe58dfd SE	399
	400	struct transform_inst_if {
	401	void *st;
	402	transform_setkey_fn *setkey;
	403	transform_delkey_fn *delkey;
	404	transform_apply_fn *forwards;
	405	transform_apply_fn *reverse;
	406	transform_destroyinstance_fn *destroy;
	407	};
	408
	409	struct transform_if {
	410	void *st;
1caa23ff IJ	411	int32_t max_start_pad; /* these three are all <<< INT_MAX */
	412	int32_t max_end_pad;
	413	int32_t keylen;
2fe58dfd SE	414	transform_createinstance_fn *create;
	415	};
	416
	417	/* NETLINK interface */
	418
70dc107b SE	419	/* Used by netlink to deliver to site, and by site to deliver to
	420	netlink. cid is the client identifier returned by
	421	netlink_regnets_fn. If buf has size 0 then the function is just
	422	being called for its site-effects (eg. making the site code attempt
	423	to bring up a network link) */
469fd1d9	424	typedef void netlink_deliver_fn(void st, struct buffer_if buf);
4efd681a	425	/* site code can tell netlink when outgoing packets will be dropped,
70dc107b	426	so netlink can generate appropriate ICMP and make routing decisions */
f208b9a9 IJ	427	#define LINK_QUALITY_UNUSED 0 /* This link is unused, do not make this netlink */
	428	#define LINK_QUALITY_DOWN 1 /* No chance of a packet being delivered right away*/
	429	#define LINK_QUALITY_DOWN_STALE_ADDRESS 2 /* Link down, old address information */
	430	#define LINK_QUALITY_DOWN_CURRENT_ADDRESS 3 /* Link down, current address information */
	431	#define LINK_QUALITY_UP 4 /* Link active */
70dc107b	432	#define MAXIMUM_LINK_QUALITY 3
469fd1d9 SE	433	typedef void netlink_link_quality_fn(void *st, uint32_t quality);
469fd1d9 SE	434	typedef void netlink_register_fn(void st, netlink_deliver_fn deliver,
1caa23ff IJ	435	void *dst, int32_t max_start_pad,
1caa23ff IJ	436	int32_t max_end_pad);
794f2398 SE	437	typedef void netlink_output_config_fn(void st, struct buffer_if buf);
794f2398 SE	438	typedef bool_t netlink_check_config_fn(void st, struct buffer_if buf);
1caa23ff	439	typedef void netlink_set_mtu_fn(void *st, int32_t new_mtu);
2fe58dfd SE	440	struct netlink_if {
2fe58dfd SE	441	void *st;
469fd1d9	442	netlink_register_fn *reg;
2fe58dfd	443	netlink_deliver_fn *deliver;
70dc107b	444	netlink_link_quality_fn *set_quality;
d3fe100d	445	netlink_set_mtu_fn *set_mtu;
2fe58dfd SE	446	};
	447
	448	/* DH interface */
	449
	450	/* Returns public key as a malloced hex string */
	451	typedef string_t dh_makepublic_fn(void st, uint8_t secret,
1caa23ff	452	int32_t secretlen);
2fe58dfd SE	453	/* Fills buffer (up to buflen) with shared secret */
2fe58dfd SE	454	typedef void dh_makeshared_fn(void st, uint8_t secret,
1caa23ff IJ	455	int32_t secretlen, cstring_t rempublic,
1caa23ff IJ	456	uint8_t *sharedsecret, int32_t buflen);
2fe58dfd SE	457	struct dh_if {
2fe58dfd SE	458	void *st;
1caa23ff	459	int32_t len; /* Approximate size of modulus in bytes */
2fe58dfd SE	460	dh_makepublic_fn *makepublic;
	461	dh_makeshared_fn *makeshared;
	462	};
	463
	464	/* HASH interface */
	465
	466	typedef void *hash_init_fn(void);
babd74ec	467	typedef void hash_update_fn(void st, const void buf, int32_t len);
2fe58dfd SE	468	typedef void hash_final_fn(void st, uint8_t digest);
2fe58dfd SE	469	struct hash_if {
1caa23ff	470	int32_t len; /* Hash output length in bytes */
2fe58dfd SE	471	hash_init_fn *init;
	472	hash_update_fn *update;
	473	hash_final_fn *final;
	474	};
	475
	476	/* BUFFER interface */
	477
	478	struct buffer_if {
	479	bool_t free;
fe5e9cc4	480	cstring_t owner; /* Set to constant string */
2fe58dfd SE	481	uint32_t flags; /* How paranoid should we be? */
	482	struct cloc loc; /* Where we were defined */
	483	uint8_t *base;
	484	uint8_t *start;
1caa23ff IJ	485	int32_t size; /* Size of buffer contents */
1caa23ff IJ	486	int32_t len; /* Total length allocated at base */
2fe58dfd SE	487	};
2fe58dfd SE	488
4f5e39ec SE	489	/*** LOG functions ***/
	490
	491	#define M_DEBUG_CONFIG 0x001
	492	#define M_DEBUG_PHASE 0x002
	493	#define M_DEBUG 0x004
	494	#define M_INFO 0x008
	495	#define M_NOTICE 0x010
	496	#define M_WARNING 0x020
	497	#define M_ERR 0x040
	498	#define M_SECURITY 0x080
	499	#define M_FATAL 0x100
	500
	501	/* The fatal() family of functions require messages that do not end in '\n' */
fe5e9cc4 SE	502	extern NORETURN(fatal(const char *message, ...));
	503	extern NORETURN(fatal_perror(const char *message, ...));
	504	extern NORETURN(fatal_status(int status, const char *message, ...));
	505	extern NORETURN(fatal_perror_status(int status, const char *message, ...));
4f5e39ec SE	506
4f5e39ec SE	507	/* The cfgfatal() family of functions require messages that end in '\n' */
fe5e9cc4 SE	508	extern NORETURN(cfgfatal(struct cloc loc, cstring_t facility,
fe5e9cc4 SE	509	const char *message, ...));
4f5e39ec SE	510	extern void cfgfile_postreadcheck(struct cloc loc, FILE *f);
4f5e39ec SE	511	extern NORETURN(vcfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
fe5e9cc4	512	cstring_t facility, const char *message,
4f5e39ec SE	513	va_list));
4f5e39ec SE	514	extern NORETURN(cfgfatal_maybefile(FILE *maybe_f, struct cloc loc,
fe5e9cc4 SE	515	cstring_t facility,
fe5e9cc4 SE	516	const char *message, ...));
4f5e39ec	517
fe5e9cc4 SE	518	extern void Message(uint32_t class, const char *message, ...)
	519	FORMAT(printf,2,3);
	520	extern void log_from_fd(int fd, cstring_t prefix, struct log_if *log);
4f5e39ec SE	521
	522	/*** END of log functions ***/
	523
45cfab8c IJ	524	#define STRING2(x) #x
	525	#define STRING(x) STRING2(x)
	526
076bb54e IJ	527	#define FILLZERO(obj) (memset(&(obj),0,sizeof((obj))))
076bb54e IJ	528
2fe58dfd	529	#endif /* secnet_h */