*/
/*
- * This version is for use with STREAMS under SunOS 4.x.
+ * This version is for use with STREAMS under SunOS 4.x,
+ * DEC Alpha OSF/1, AIX 4.x, and SVR4 systems including Solaris 2.
*
- * $Id: bsd-comp.c,v 1.4 1994/09/16 02:06:31 paulus Exp $
+ * $Id: bsd-comp.c,v 1.13 1995/05/29 06:34:33 paulus Exp $
*/
+#ifdef __aix4__
+#include <net/net_globals.h>
+#endif
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stream.h>
-#include <sys/kmem_alloc.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include <net/ppp_defs.h>
#include <net/ppp_str.h>
-#define PACKET mblk_t
+#ifdef __svr4__ /* SVR4, including SunOS 5.x */
+# include <sys/kmem.h>
+# define ALLOCATE(n) kmem_alloc((n), KM_NOSLEEP)
+# define FREE(p, n) kmem_free((p), (n))
+#else /* SunOS 4.x */
+# ifdef sun
+# include <sys/kmem_alloc.h>
+# define ALLOCATE(n) kmem_alloc((n), KMEM_NOSLEEP)
+# define FREE(p, n) kmem_free((p), (n))
+# endif
+#endif
+
+#ifdef __osf__
+#ifdef FIRST
+#undef FIRST
+#undef LAST
+#endif
+#ifdef FREE
+#undef FREE
+#endif
+#include <kern/kalloc.h>
+#define ALLOCATE(n) kalloc((n))
+#define FREE(p, n) kfree((p), (n))
+#endif
+
+#ifdef __aix4__
+#define ALLOCATE(n) xmalloc((n), 0, pinned_heap)
+#define FREE(p, n) xmfree((p), pinned_heap)
+#endif
+
+#define PACKETPTR mblk_t *
#include <net/ppp-comp.h>
+#if DO_BSD_COMPRESS
+
/*
* PPP "BSD compress" compression
* The differences between this compression and the classic BSD LZW
* compression is not going well.
*/
-/*
- * Macros to extract protocol version and number of bits
- * from the third byte of the BSD Compress CCP configuration option.
- */
-#define BSD_VERSION(x) ((x) >> 5)
-#define BSD_NBITS(x) ((x) & 0x1F)
-
-#define BSD_CURRENT_VERSION 1
-
/*
* A dictionary for doing BSD compress.
*/
u_char maxbits;
u_char debug;
u_char unit;
- u_short mru;
u_short seqno; /* sequence number of next packet */
+ u_int hdrlen; /* header length to preallocate */
+ u_int mru;
u_int maxmaxcode; /* largest valid code */
u_int max_ent; /* largest code in use */
- u_int in_count; /* uncompressed bytes */
- u_int bytes_out; /* compressed bytes */
+ u_int in_count; /* uncompressed bytes, aged */
+ u_int bytes_out; /* compressed bytes, aged */
u_int ratio; /* recent compression ratio */
- u_int checkpoint; /* when to next check the ratio */
- int clear_count; /* times dictionary cleared */
- int incomp_count; /* incompressible packets */
+ u_int checkpoint; /* when to next check the ratio */
+ u_int clear_count; /* times dictionary cleared */
+ u_int incomp_count; /* incompressible packets */
+ u_int incomp_bytes; /* incompressible bytes */
+ u_int uncomp_count; /* uncompressed packets */
+ u_int uncomp_bytes; /* uncompressed bytes */
+ u_int comp_count; /* compressed packets */
+ u_int comp_bytes; /* compressed bytes */
u_short *lens; /* array of lengths of codes */
struct bsd_dict {
union { /* hash value */
};
#define BSD_OVHD 2 /* BSD compress overhead/packet */
-#define MIN_BSD_BITS 9
-#define BSD_INIT_BITS MIN_BSD_BITS
-#define MAX_BSD_BITS 15
+#define BSD_INIT_BITS BSD_MIN_BITS
static void *bsd_comp_alloc __P((u_char *options, int opt_len));
static void *bsd_decomp_alloc __P((u_char *options, int opt_len));
static void bsd_free __P((void *state));
static int bsd_comp_init __P((void *state, u_char *options, int opt_len,
- int unit, int debug));
+ int unit, int hdrlen, int debug));
static int bsd_decomp_init __P((void *state, u_char *options, int opt_len,
- int unit, int mru, int debug));
+ int unit, int hdrlen, int mru, int debug));
static int bsd_compress __P((void *state, mblk_t **mret,
mblk_t *mp, int slen, int maxolen));
static void bsd_incomp __P((void *state, mblk_t *dmsg));
static int bsd_decompress __P((void *state, mblk_t *cmp, mblk_t **dmpp));
static void bsd_reset __P((void *state));
+static void bsd_comp_stats __P((void *state, struct compstat *stats));
/*
* Procedures exported to ppp_comp.c.
*/
struct compressor ppp_bsd_compress = {
- 0x21, /* compress_proto */
+ CI_BSD_COMPRESS, /* compress_proto */
bsd_comp_alloc, /* comp_alloc */
bsd_free, /* comp_free */
bsd_comp_init, /* comp_init */
bsd_reset, /* comp_reset */
bsd_compress, /* compress */
+ bsd_comp_stats, /* comp_stat */
bsd_decomp_alloc, /* decomp_alloc */
bsd_free, /* decomp_free */
bsd_decomp_init, /* decomp_init */
bsd_reset, /* decomp_reset */
bsd_decompress, /* decompress */
bsd_incomp, /* incomp */
+ bsd_comp_stats, /* decomp_stat */
};
/*
#define LAST 255
#define MAXCODE(b) ((1 << (b)) - 1)
-#define BADCODEM1 MAXCODE(MAX_BSD_BITS);
+#define BADCODEM1 MAXCODE(BSD_MAX_BITS)
#define BSD_HASH(prefix,suffix,hshift) ((((u_int32_t)(suffix)) << (hshift)) \
^ (u_int32_t)(prefix))
return 0;
}
+/*
+ * Return statistics.
+ */
+static void
+bsd_comp_stats(state, stats)
+ void *state;
+ struct compstat *stats;
+{
+ struct bsd_db *db = (struct bsd_db *) state;
+ u_int out;
+
+ stats->unc_bytes = db->uncomp_bytes;
+ stats->unc_packets = db->uncomp_count;
+ stats->comp_bytes = db->comp_bytes;
+ stats->comp_packets = db->comp_count;
+ stats->inc_bytes = db->incomp_bytes;
+ stats->inc_packets = db->incomp_count;
+ stats->ratio = db->in_count;
+ out = db->bytes_out;
+ if (stats->ratio <= 0x7fffff)
+ stats->ratio <<= 8;
+ else
+ out >>= 8;
+ if (out != 0)
+ stats->ratio /= out;
+}
+
/*
* Reset state, as on a CCP ResetReq.
*/
u_int newlen, hsize, hshift, maxmaxcode;
struct bsd_db *db;
- if (opt_len != 3 || options[0] != 0x21 || options[1] != 3
+ if (opt_len != 3 || options[0] != CI_BSD_COMPRESS || options[1] != 3
|| BSD_VERSION(options[2]) != BSD_CURRENT_VERSION)
return NULL;
bits = BSD_NBITS(options[2]);
maxmaxcode = MAXCODE(bits);
newlen = sizeof(*db) + (hsize-1) * (sizeof(db->dict[0]));
- db = (struct bsd_db *) kmem_alloc(newlen, KMEM_NOSLEEP);
+ db = (struct bsd_db *) ALLOCATE(newlen);
if (!db)
return NULL;
bzero(db, sizeof(*db) - sizeof(db->dict));
if (!decomp) {
db->lens = NULL;
} else {
- db->lens = (u_short *) kmem_alloc((maxmaxcode+1) * sizeof(db->lens[0]),
- KMEM_NOSLEEP);
+ db->lens = (u_short *) ALLOCATE((maxmaxcode+1) * sizeof(db->lens[0]));
if (!db->lens) {
- kmem_free(db, newlen);
+ FREE(db, newlen);
return NULL;
}
}
struct bsd_db *db = (struct bsd_db *) state;
if (db->lens)
- kmem_free(db->lens, (db->maxmaxcode+1) * sizeof(db->lens[0]));
- kmem_free(db, db->totlen);
+ FREE(db->lens, (db->maxmaxcode+1) * sizeof(db->lens[0]));
+ FREE(db, db->totlen);
}
static void *
* Initialize the database.
*/
static int
-bsd_init(db, options, opt_len, unit, mru, debug, decomp)
+bsd_init(db, options, opt_len, unit, hdrlen, mru, debug, decomp)
struct bsd_db *db;
u_char *options;
- int opt_len, unit, mru, debug, decomp;
+ int opt_len, unit, hdrlen, mru, debug, decomp;
{
int i;
- if (opt_len != 3 || options[0] != 0x21 || options[1] != 3
+ if (opt_len != 3 || options[0] != CI_BSD_COMPRESS || options[1] != 3
|| BSD_VERSION(options[2]) != BSD_CURRENT_VERSION
|| BSD_NBITS(options[2]) != db->maxbits
|| decomp && db->lens == NULL)
}
db->unit = unit;
+ db->hdrlen = hdrlen;
db->mru = mru;
- db->clear_count = -1;
if (debug)
db->debug = 1;
- bsd_clear(db);
+ bsd_reset(db);
return 1;
}
static int
-bsd_comp_init(state, options, opt_len, unit, debug)
+bsd_comp_init(state, options, opt_len, unit, hdrlen, debug)
void *state;
u_char *options;
- int opt_len, unit, debug;
+ int opt_len, unit, hdrlen, debug;
{
return bsd_init((struct bsd_db *) state, options, opt_len,
- unit, 0, debug, 0);
+ unit, hdrlen, 0, debug, 0);
}
static int
-bsd_decomp_init(state, options, opt_len, unit, mru, debug)
+bsd_decomp_init(state, options, opt_len, unit, hdrlen, mru, debug)
void *state;
u_char *options;
- int opt_len, unit, mru, debug;
+ int opt_len, unit, hdrlen, mru, debug;
{
return bsd_init((struct bsd_db *) state, options, opt_len,
- unit, mru, debug, 1);
+ unit, hdrlen, mru, debug, 1);
}
-
/*
* compress a packet
* One change from the BSD compress command is that when the
* code size expands, we do not output a bunch of padding.
+ *
+ * N.B. at present, we ignore the hdrlen specified in the comp_init call.
*/
static int /* new slen */
bsd_compress(state, mretp, mp, slen, maxolen)
u_int32_t accm = 0, fcode;
struct bsd_dict *dictp;
u_char c;
- int hval, disp, ent;
+ int hval, disp, ent, ilen;
mblk_t *np, *mret;
u_char *rptr, *wptr;
u_char *cp_end;
rptr += PPP_HDRLEN;
slen = mp->b_wptr - rptr;
- db->in_count += slen + 1;
+ ilen = slen + 1;
np = mp->b_cont;
for (;;) {
if (slen <= 0) {
np = np->b_cont;
if (!slen)
continue; /* handle 0-length buffers */
- db->in_count += slen;
+ ilen += slen;
}
slen--;
if (dictp->codem1 >= max_ent)
goto nomatch;
} while (dictp->f.fcode != fcode);
- ent = dictp->codem1+1; /* finally found (prefix,suffix) */
+ ent = dictp->codem1 + 1; /* finally found (prefix,suffix) */
continue;
nomatch:
ent = c;
}
- OUTPUT(ent); /* output the last code */
+ OUTPUT(ent); /* output the last code */
db->bytes_out += olen;
+ db->in_count += ilen;
+ if (bitno < 32)
+ ++db->bytes_out; /* count complete bytes */
if (bsd_check(db))
- OUTPUT(CLEAR); /* do not count the CLEAR */
+ OUTPUT(CLEAR); /* do not count the CLEAR */
/*
* Pad dribble bits of last code with ones.
if (max_ent >= MAXCODE(n_bits) && max_ent < db->maxmaxcode)
db->n_bits++;
+ db->uncomp_bytes += ilen;
+ ++db->uncomp_count;
if (olen + PPP_HDRLEN + BSD_OVHD > maxolen && mret != NULL) {
/* throw away the compressed stuff if it is longer than uncompressed */
freemsg(mret);
mret = NULL;
+ ++db->incomp_count;
+ db->incomp_bytes += ilen;
} else if (wptr != NULL) {
m->b_wptr = wptr;
if (m->b_cont) {
freemsg(m->b_cont);
m->b_cont = NULL;
}
+ ++db->comp_count;
+ db->comp_bytes += olen + BSD_OVHD;
}
*mretp = mret;
u_int32_t fcode;
u_char c;
long hval, disp;
- int slen;
+ int slen, ilen;
u_int bitno = 7;
u_char *rptr;
u_int ent;
db->incomp_count++;
db->seqno++;
- db->in_count++; /* count the protocol as 1 byte */
+ ilen = 1; /* count the protocol as 1 byte */
rptr += PPP_HDRLEN;
for (;;) {
slen = dmsg->b_wptr - rptr;
rptr = dmsg->b_rptr;
continue; /* skip zero-length buffers */
}
- db->in_count += slen;
+ ilen += slen;
do {
c = *rptr++;
}
bitno += n_bits; /* output (count) the last code */
db->bytes_out += bitno/8;
+ db->in_count += ilen;
(void)bsd_check(db);
+ ++db->incomp_count;
+ db->incomp_bytes += ilen;
+ ++db->uncomp_count;
+ db->uncomp_bytes += ilen;
+
/* Increase code size if we would have without the packet
* boundary and as the decompressor will.
*/
/*
* Decompress "BSD Compress"
+ *
+ * Because of patent problems, we return DECOMP_ERROR for errors
+ * found by inspecting the input data and for system problems, but
+ * DECOMP_FATALERROR for any errors which could possibly be said to
+ * be being detected "after" decompression. For DECOMP_ERROR,
+ * we can issue a CCP reset-request; for DECOMP_FATALERROR, we may be
+ * infringing a patent of Motorola's if we do, so we take CCP down
+ * instead.
+ *
+ * Given that the frame has the correct sequence number and a good FCS,
+ * errors such as invalid codes in the input most likely indicate a
+ * bug, so we return DECOMP_FATALERROR for them in order to turn off
+ * compression, even though they are detected by inspecting the input.
*/
static int
bsd_decompress(state, cmsg, dmpp)
u_int incode, oldcode, finchar;
u_char *p, *rptr, *wptr;
mblk_t *dmsg, *mret;
- int adrs, ctrl;
+ int adrs, ctrl, ilen;
int dlen, space, codelen, extra;
/*
rptr += PPP_HDRLEN;
seq = (rptr[0] << 8) + rptr[1];
rptr += BSD_OVHD;
- len = cmsg->b_wptr - rptr;
+ ilen = len = cmsg->b_wptr - rptr;
/*
* Check the sequence number and give up if it is not what we expect.
/*
* Allocate one message block to start with.
*/
- if ((dmsg = allocb(DECOMP_CHUNK, BPRI_MED)) == NULL)
+ if ((dmsg = allocb(DECOMP_CHUNK + db->hdrlen, BPRI_MED)) == NULL)
return DECOMP_ERROR;
mret = dmsg;
+ dmsg->b_wptr += db->hdrlen;
dmsg->b_rptr = wptr = dmsg->b_wptr;
/* Fill in the ppp header, but not the last byte of the protocol
wptr += PPP_HDRLEN - 1;
space = dmsg->b_datap->db_lim - wptr;
- db->bytes_out += len;
oldcode = CLEAR;
explen = 0;
for (;;) {
break;
rptr = cmsg->b_rptr;
len = cmsg->b_wptr - rptr;
- db->bytes_out += len;
+ ilen += len;
continue; /* handle 0-length buffers */
}
}
}
bsd_clear(db);
- explen = 0;
+ explen = ilen = 0;
break;
}
- if (incode > max_ent+2 || incode > db->maxmaxcode
+ if (incode > max_ent + 2 || incode > db->maxmaxcode
|| incode > max_ent && oldcode == CLEAR) {
freemsg(dmsg);
if (db->debug) {
printf("max_ent=0x%x dlen=%d seqno=%d\n",
max_ent, dlen, db->seqno);
}
- return DECOMP_FATALERROR;
+ return DECOMP_FATALERROR; /* probably a bug */
}
/* Special case for KwKwK string. */
* Keep the checkpoint right so that incompressible packets
* clear the dictionary at the right times.
*/
+ db->bytes_out += ilen;
db->in_count += explen;
if (bsd_check(db) && db->debug) {
printf("bsd_decomp%d: peer should have cleared dictionary\n",
db->unit);
}
+ ++db->comp_count;
+ db->comp_bytes += ilen + BSD_OVHD;
+ ++db->uncomp_count;
+ db->uncomp_bytes += explen;
+
*dmpp = mret;
return DECOMP_OK;
}
+#endif /* DO_BSD_COMPRESS */