NetBSD/dist/ntp/ntpd/ntp_peer.c

816 lines
19 KiB
C

/* $NetBSD: ntp_peer.c,v 1.1.1.2 2000/04/22 14:53:18 simonb Exp $ */
/*
* ntp_peer.c - management of data maintained for peer associations
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <sys/types.h>
#include "ntpd.h"
#include "ntp_stdlib.h"
#ifdef AUTOKEY
#include "ntp_crypto.h"
#endif /* AUTOKEY */
/*
* Table of valid association combinations
* ---------------------------------------
*
* packet->mode
* peer->mode | UNSPEC ACTIVE PASSIVE CLIENT SERVER BCAST
* ---------- | ---------------------------------------------
* NO_PEER | e 1 e 1 1 1
* ACTIVE | e 1 1 0 0 0
* PASSIVE | e 1 e 0 0 0
* CLIENT | e 0 0 0 1 1
* SERVER | e 0 0 0 0 0
* BCAST | e 0 0 0 0 0
* CONTROL | e 0 0 0 0 0
* PRIVATE | e 0 0 0 0 0
* BCLIENT | e 0 0 0 e 1
* MCLIENT | e 0 0 0 0 0
*
* One point to note here:
* a packet in BCAST mode can potentially match a peer in CLIENT
* mode, but we that is a special case and we check for that early
* in the decision process. This avoids having to keep track of
* what kind of associations are possible etc... We actually
* circumvent that problem by requiring that the first b(m)roadcast
* received after the change back to BCLIENT mode sets the clock.
*/
int AM[AM_MODES][AM_MODES] = {
/* { UNSPEC, ACTIVE, PASSIVE, CLIENT, SERVER, BCAST } */
/*NONE*/{ AM_ERR, AM_NEWPASS, AM_ERR, AM_FXMIT, AM_MANYCAST, AM_NEWBCL},
/*A*/ { AM_ERR, AM_PROCPKT, AM_PROCPKT, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH},
/*P*/ { AM_ERR, AM_PROCPKT, AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH},
/*C*/ { AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_PROCPKT, AM_POSSBCL},
/*S*/ { AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH},
/*BCST*/{ AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH},
/*CNTL*/{ AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH},
/*PRIV*/{ AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH},
/*BCL*/ { AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_ERR, AM_PROCPKT},
/*MCL*/ { AM_ERR, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH, AM_NOMATCH}
};
#define MATCH_ASSOC(x,y) AM[(x)][(y)]
/*
* These routines manage the allocation of memory to peer structures
* and the maintenance of the peer hash table. The two main entry
* points are findpeer(), which looks for corresponding peer data
* in the peer list, newpeer(), which allocates a new peer structure
* and adds it to the list, and unpeer(), which demobilizes the association
* and deallocates the structure.
*/
/*
* The peer hash table (imported by the protocol module).
*/
struct peer *peer_hash[HASH_SIZE];
int peer_hash_count[HASH_SIZE]; /* count of peers in each bucket */
/*
* The association ID hash table. Used for lookups by association ID
*/
struct peer *assoc_hash[HASH_SIZE];
int assoc_hash_count[HASH_SIZE];
/*
* The free list. Clean structures only, please.
*/
static struct peer *peer_free;
int peer_free_count;
/*
* Association ID. We initialize this value randomly, the assign a new
* value every time the peer structure is incremented.
*/
static u_short current_association_ID;
/*
* Memory allocation watermarks.
*/
#define INIT_PEER_ALLOC 15 /* initialize space for 15 peers */
#define INC_PEER_ALLOC 5 /* when we run out, add 5 more */
/*
* Miscellaneous statistic counters which may be queried.
*/
u_long peer_timereset; /* time stat counters were zeroed */
u_long findpeer_calls; /* number of calls to findpeer */
u_long assocpeer_calls; /* number of calls to findpeerbyassoc */
u_long peer_allocations; /* number of allocations from the free list */
u_long peer_demobilizations; /* number of structs freed to free list */
int total_peer_structs; /* number of peer structs in circulation */
int peer_associations; /* number of active associations */
/*
* Our initial allocation of peer space
*/
static struct peer init_peer_alloc[INIT_PEER_ALLOC];
/*
* Initialization data. When configuring peers at initialization time,
* we try to get their poll update timers initialized to different values
* to prevent us from sending big clumps of data all at once.
*/
/* static u_long init_peer_starttime; */
static void getmorepeermem P((void));
/*
* init_peer - initialize peer data structures and counters
*
* N.B. We use the random number routine in here. It had better be
* initialized prior to getting here.
*/
void
init_peer(void)
{
register int i;
/*
* Clear hash table and counters.
*/
for (i = 0; i < HASH_SIZE; i++) {
peer_hash[i] = 0;
peer_hash_count[i] = 0;
assoc_hash[i] = 0;
assoc_hash_count[i] = 0;
}
/*
* Clear stat counters
*/
findpeer_calls = peer_allocations = 0;
assocpeer_calls = peer_demobilizations = 0;
/*
* Initialization counter.
*/
/* init_peer_starttime = 0; */
/*
* Initialize peer memory.
*/
peer_free = 0;
for (i = 0; i < INIT_PEER_ALLOC; i++) {
init_peer_alloc[i].next = peer_free;
peer_free = &init_peer_alloc[i];
}
total_peer_structs = INIT_PEER_ALLOC;
peer_free_count = INIT_PEER_ALLOC;
/*
* Initialize our first association ID
*/
current_association_ID = (u_short)ranp2(16);
if (current_association_ID == 0)
current_association_ID = 1;
}
/*
* getmorepeermem - add more peer structures to the free list
*/
static void
getmorepeermem(void)
{
register int i;
register struct peer *peer;
peer = (struct peer *)emalloc(INC_PEER_ALLOC*sizeof(struct peer));
for (i = 0; i < INC_PEER_ALLOC; i++) {
peer->next = peer_free;
peer_free = peer;
peer++;
}
total_peer_structs += INC_PEER_ALLOC;
peer_free_count += INC_PEER_ALLOC;
}
/*
* findexistingpeer - return a pointer to a peer in the hash table
*/
struct peer *
findexistingpeer(
struct sockaddr_in *addr,
struct peer *start_peer,
int mode
)
{
register struct peer *peer;
/*
* start_peer is included so we can locate instances of the
* same peer through different interfaces in the hash table.
*/
if (start_peer == 0)
peer = peer_hash[HASH_ADDR(addr)];
else
peer = start_peer->next;
while (peer != 0) {
if (NSRCADR(addr) == NSRCADR(&peer->srcadr)
&& NSRCPORT(addr) == NSRCPORT(&peer->srcadr)) {
if (mode == -1)
return peer;
else if (peer->hmode == mode)
break;
}
peer = peer->next;
}
return peer;
}
/*
* findpeer - find and return a peer in the hash table.
*/
struct peer *
findpeer(
struct sockaddr_in *srcadr,
struct interface *dstadr,
int fd,
int pkt_mode,
int *action
)
{
register struct peer *peer;
int hash;
findpeer_calls++;
hash = HASH_ADDR(srcadr);
for (peer = peer_hash[hash]; peer != 0; peer = peer->next) {
if (NSRCADR(srcadr) == NSRCADR(&peer->srcadr)
&& NSRCPORT(srcadr) == NSRCPORT(&peer->srcadr)) {
/*
* if the association matching rules determine that
* this is not a valid combination, then look for
* the next valid peer association.
*/
*action = MATCH_ASSOC(peer->hmode, pkt_mode);
/*
* Sigh! Check if BCLIENT peer in client
* server mode, else return error
*/
if ((*action == AM_POSSBCL) &&
!(peer->cast_flags & FLAG_MCAST1)) {
*action = AM_ERR;
}
/* if an error was returned, exit back right here */
if (*action == AM_ERR)
return (struct peer *)0;
/* if a match is found, we stop our search */
if (*action != AM_NOMATCH)
break;
}
}
/*
* If no matching association is found
*/
if (peer == 0) {
*action = MATCH_ASSOC(NO_PEER, pkt_mode);
return (struct peer *)0;
}
/*
* Reset the default interface to something more meaningful
*/
if ((peer->dstadr == any_interface))
peer->dstadr = dstadr;
return peer;
}
/*
* findpeerbyassocid - find and return a peer using his association ID
*/
struct peer *
findpeerbyassoc(
int assoc
)
{
register struct peer *peer;
int hash;
assocpeer_calls++;
hash = assoc & HASH_MASK;
for (peer = assoc_hash[hash]; peer != 0; peer = peer->ass_next) {
if ((u_short)assoc == peer->associd)
return peer; /* got it! */
}
/*
* Out of luck. Return 0.
*/
return (struct peer *)0;
}
/*
* findmanycastpeer - find and return an manycast peer if it exists
*
*
* the current implementation loops across all hash-buckets
*
* *** THERE IS AN URGENT NEED TO CHANGE THIS ***
*/
struct peer *
findmanycastpeer(
l_fp *p_org
)
{
register struct peer *peer;
register struct peer *manycast_peer = 0;
int i = 0;
for (i = 0; i < HASH_SIZE; i++) {
if (peer_hash_count[i] == 0)
continue;
for (peer = peer_hash[i]; peer != 0; peer = peer->next) {
if (peer->cast_flags & MDF_ACAST &&
peer->flags & FLAG_CONFIG) {
if (L_ISEQU(&peer->xmt, p_org))
return peer; /* got it */
else
manycast_peer = peer;
}
}
}
/*
* Out of luck. Return the manycastpeer for what it is worth.
*/
return manycast_peer;
}
/*
* clear_all - flush all time values and refresh Diffie-Hellman public
* value.
*/
void
clear_all(void)
{
struct peer *peer, *next_peer;
int n;
for (n = 0; n < HASH_SIZE; n++) {
for (peer = peer_hash[n]; peer != 0; peer = next_peer) {
next_peer = peer->next;
peer_clear(peer);
}
}
#ifdef DEBUG
if (debug)
printf("clear_all: at %lu\n", current_time);
#endif
}
#ifdef AUTOKEY
/*
* expire_all - flush all crypto data and update timestamp
*/
void
expire_all(void)
{
struct peer *peer, *next_peer;
int n;
for (n = 0; n < HASH_SIZE; n++) {
for (peer = peer_hash[n]; peer != 0; peer = next_peer) {
next_peer = peer->next;
key_expire(peer);
peer->pcookie.tstamp = 0;
}
}
sys_private = (u_int32)RANDOM & 0xffffffff;
L_CLR(&sys_revoketime);
if (sys_leap != LEAP_NOTINSYNC)
get_systime(&sys_revoketime);
#ifdef PUBKEY
if (crypto_enable)
crypto_agree();
#endif /* PUBKEY */
#ifdef DEBUG
if (debug)
printf("expire_all: at %lu\n", current_time);
#endif
}
#endif /* AUTOKEY */
/*
* unpeer - remove peer structure from hash table and free structure
*/
void
unpeer(
struct peer *peer_to_remove
)
{
int hash;
peer_associations--;
#ifdef DEBUG
if (debug)
printf("demobilize %u %d\n", peer_to_remove->associd,
peer_associations);
#endif
peer_clear(peer_to_remove);
if (peer_to_remove->keystr != 0)
free(peer_to_remove->keystr);
#ifdef PUBKEY
if (peer_to_remove->pubkey != 0)
free(peer_to_remove->pubkey);
#endif /* PUBKEY */
hash = HASH_ADDR(&peer_to_remove->srcadr);
peer_hash_count[hash]--;
peer_demobilizations++;
#ifdef REFCLOCK
/*
* If this peer is actually a clock, shut it down first
*/
if (peer_to_remove->flags & FLAG_REFCLOCK)
refclock_unpeer(peer_to_remove);
#endif
peer_to_remove->action = 0; /* disable timeout actions */
if (peer_hash[hash] == peer_to_remove)
peer_hash[hash] = peer_to_remove->next;
else {
register struct peer *peer;
peer = peer_hash[hash];
while (peer != 0 && peer->next != peer_to_remove)
peer = peer->next;
if (peer == 0) {
peer_hash_count[hash]++;
msyslog(LOG_ERR, "peer struct for %s not in table!",
ntoa(&peer->srcadr));
} else {
peer->next = peer_to_remove->next;
}
}
/*
* Remove him from the association hash as well.
*/
hash = peer_to_remove->associd & HASH_MASK;
assoc_hash_count[hash]--;
if (assoc_hash[hash] == peer_to_remove)
assoc_hash[hash] = peer_to_remove->ass_next;
else {
register struct peer *peer;
peer = assoc_hash[hash];
while (peer != 0 && peer->ass_next != peer_to_remove)
peer = peer->ass_next;
if (peer == 0) {
assoc_hash_count[hash]++;
msyslog(LOG_ERR,
"peer struct for %s not in association table!",
ntoa(&peer->srcadr));
} else {
peer->ass_next = peer_to_remove->ass_next;
}
}
peer_to_remove->next = peer_free;
peer_free = peer_to_remove;
peer_free_count++;
}
/*
* peer_config - configure a new peer
*/
struct peer *
peer_config(
struct sockaddr_in *srcadr,
struct interface *dstadr,
int hmode,
int version,
int minpoll,
int maxpoll,
int flags,
int ttl,
keyid_t key,
u_char *keystr
)
{
register struct peer *peer;
/*
* See if we have this guy in the tables already. If
* so just mark him configured.
*/
peer = findexistingpeer(srcadr, (struct peer *)0, hmode);
if (dstadr != 0) {
while (peer != 0) {
if (peer->dstadr == dstadr)
break;
peer = findexistingpeer(srcadr, peer, hmode);
}
}
/*
* If we found one, just change his mode and mark him configured.
*/
if (peer != 0) {
peer->hmode = (u_char)hmode;
peer->version = (u_char)version;
peer->minpoll = (u_char)minpoll;
peer->maxpoll = (u_char)maxpoll;
peer->hpoll = peer->minpoll;
peer->ppoll = peer->minpoll;
peer->flags = flags | FLAG_CONFIG |
(peer->flags & FLAG_REFCLOCK);
peer->cast_flags = (hmode == MODE_BROADCAST) ?
IN_CLASSD(ntohl(srcadr->sin_addr.s_addr)) ?
MDF_MCAST : MDF_BCAST : MDF_UCAST;
peer->ttl = (u_char)ttl;
peer->keyid = key;
} else {
/*
* If we're here this guy is unknown to us. Make a new peer
* structure for him.
*/
peer = newpeer(srcadr, dstadr, hmode, version, minpoll,
maxpoll, ttl, key);
if (peer == 0)
return (peer);
peer->flags |= flags | FLAG_CONFIG;
}
#ifdef DEBUG
if (debug)
printf(
"peer_config: %s mode %d vers %d min %d max %d flags 0x%04x ttl %d key %08x\n",
ntoa(&peer->srcadr), peer->hmode, peer->version,
peer->minpoll, peer->maxpoll, peer->flags, peer->ttl,
peer->keyid);
#endif
#ifdef PUBKEY
if (!(peer->flags & FLAG_SKEY) || peer->hmode == MODE_BROADCAST)
return (peer);
crypto_public(peer, keystr);
#endif /* PUBKEY */
return (peer);
}
/*
* newpeer - initialize a new peer association
*/
struct peer *
newpeer(
struct sockaddr_in *srcadr,
struct interface *dstadr,
int hmode,
int version,
int minpoll,
int maxpoll,
int ttl,
u_long key
)
{
register struct peer *peer;
register int i;
/*
* Some dirt here. Some of the initialization requires
* knowlege of our system state.
*/
if (peer_free_count == 0)
getmorepeermem();
peer = peer_free;
peer_free = peer->next;
peer_free_count--;
peer_associations++;
/*
* Initialize the structure. This stuff is sort of part of
* the receive procedure and part of the clear procedure rolled
* into one.
*
* Zero the whole thing for now. We might be pickier later.
*/
memset((char *)peer, 0, sizeof(struct peer));
peer->srcadr = *srcadr;
if (dstadr != 0)
peer->dstadr = dstadr;
else if (hmode == MODE_BROADCAST)
peer->dstadr = findbcastinter(srcadr);
else
peer->dstadr = any_interface;
peer->cast_flags = (hmode == MODE_BROADCAST) ?
(IN_CLASSD(ntohl(srcadr->sin_addr.s_addr))) ? MDF_MCAST :
MDF_BCAST : (hmode == MODE_BCLIENT || hmode == MODE_MCLIENT) ?
(peer->dstadr->flags & INT_MULTICAST) ? MDF_MCAST : MDF_BCAST :
MDF_UCAST;
/* Set manycast flags if appropriate */
if (IN_CLASSD(ntohl(srcadr->sin_addr.s_addr)) && hmode == MODE_CLIENT)
peer->cast_flags = MDF_ACAST;
peer->hmode = (u_char)hmode;
peer->keyid = key;
peer->version = (u_char)version;
peer->minpoll = (u_char)minpoll;
peer->maxpoll = (u_char)maxpoll;
peer->hpoll = peer->minpoll;
peer->ppoll = peer->minpoll;
peer->ttl = ttl;
peer->leap = LEAP_NOTINSYNC;
peer->precision = sys_precision;
peer->variance = MAXDISPERSE;
peer->epoch = current_time;
peer->stratum = STRATUM_UNSPEC;
peer_clear(peer);
peer->update = peer->outdate = current_time;
peer->nextdate = peer->outdate + RANDPOLL(NTP_MINPOLL);
/*
* Assign him an association ID and increment the system variable
*/
peer->associd = current_association_ID;
if (++current_association_ID == 0)
++current_association_ID;
/*
* Note time on statistics timers.
*/
peer->timereset = current_time;
peer->timereachable = current_time;
peer->timereceived = current_time;
#ifdef REFCLOCK
if (ISREFCLOCKADR(&peer->srcadr)) {
/*
* We let the reference clock support do clock
* dependent initialization. This includes setting
* the peer timer, since the clock may have requirements
* for this.
*/
if (!refclock_newpeer(peer)) {
/*
* Dump it, something screwed up
*/
peer->next = peer_free;
peer_free = peer;
peer_free_count++;
return 0;
}
}
#endif
/*
* Put him in the hash tables.
*/
i = HASH_ADDR(&peer->srcadr);
peer->next = peer_hash[i];
peer_hash[i] = peer;
peer_hash_count[i]++;
i = peer->associd & HASH_MASK;
peer->ass_next = assoc_hash[i];
assoc_hash[i] = peer;
assoc_hash_count[i]++;
#ifdef DEBUG
if (debug)
printf("mobilize %u %d next %lu\n", peer->associd,
peer_associations, peer->nextdate - peer->outdate);
#endif
return peer;
}
/*
* peer_unconfig - remove the configuration bit from a peer
*/
int
peer_unconfig(
struct sockaddr_in *srcadr,
struct interface *dstadr,
int mode
)
{
register struct peer *peer;
int num_found;
num_found = 0;
peer = findexistingpeer(srcadr, (struct peer *)0, mode);
while (peer != 0) {
if (peer->flags & FLAG_CONFIG
&& (dstadr == 0 || peer->dstadr == dstadr)) {
num_found++;
/*
* Tricky stuff here. If the peer is polling us
* in active mode, turn off the configuration bit
* and make the mode passive. This allows us to
* avoid dumping a lot of history for peers we
* might choose to keep track of in passive mode.
* The protocol will eventually terminate undesirables
* on its own.
*/
if (peer->hmode == MODE_ACTIVE
&& peer->pmode == MODE_ACTIVE) {
peer->hmode = MODE_PASSIVE;
peer->flags &= ~FLAG_CONFIG;
} else {
unpeer(peer);
peer = 0;
}
}
peer = findexistingpeer(srcadr, peer, mode);
}
return num_found;
}
/*
* peer_copy_manycast - copy manycast peer variables to new association
* (right now it simply copies the transmit timestamp)
*/
void
peer_config_manycast(
struct peer *peer1,
struct peer *peer2
)
{
peer2->cast_flags = MDF_ACAST;
peer2->xmt = peer1->xmt;
}
/*
* peer_clr_stats - clear peer module stat counters
*/
void
peer_clr_stats(void)
{
findpeer_calls = 0;
assocpeer_calls = 0;
peer_allocations = 0;
peer_demobilizations = 0;
peer_timereset = current_time;
}
/*
* peer_reset - reset stat counters in a peer structure
*/
void
peer_reset(
struct peer *peer
)
{
if (peer == 0)
return;
peer->sent = 0;
peer->received = 0;
peer->processed = 0;
peer->badauth = 0;
peer->bogusorg = 0;
peer->oldpkt = 0;
peer->seldisptoolarge = 0;
peer->selbroken = 0;
peer->timereset = current_time;
}
/*
* peer_all_reset - reset all peer stat counters
*/
void
peer_all_reset(void)
{
struct peer *peer;
int hash;
for (hash = 0; hash < HASH_SIZE; hash++)
for (peer = peer_hash[hash]; peer != 0; peer = peer->next)
peer_reset(peer);
}