*/
/*
- * This version is for use with STREAMS under SunOS 4.x.
+ * This version is for use with STREAMS under SunOS 4.x,
+ * Digital UNIX, AIX 4.x, and SVR4 systems including Solaris 2.
*
- * $Id: bsd-comp.c,v 1.5 1994/10/21 06:30:15 paulus Exp $
+ * $Id: bsd-comp.c,v 1.20 1996/08/28 06:31:57 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>
+#include "ppp_mod.h"
+
+#ifdef SVR4
+#include <sys/byteorder.h>
+#ifndef _BIG_ENDIAN
+#define BSD_LITTLE_ENDIAN
+#endif
+#endif
+
+#ifdef __osf__
+#undef FIRST
+#undef LAST
+#define BSD_LITTLE_ENDIAN
+#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, aged */
};
#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));
* 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 */
#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))
db->ratio = 0;
db->bytes_out = 0;
db->in_count = 0;
- db->incomp_count = 0;
db->checkpoint = CHECK_GAP;
}
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_packets = db->comp_count;
stats->inc_bytes = db->incomp_bytes;
stats->inc_packets = db->incomp_count;
- stats->ratio = (double) db->in_count;
- if (db->bytes_out != 0)
- stats->ratio /= db->bytes_out;
+ 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;
}
/*
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]);
switch (bits) {
case 9: /* needs 82152 for both directions */
maxmaxcode = MAXCODE(bits);
newlen = sizeof(*db) + (hsize-1) * (sizeof(db->dict[0]));
- db = (struct bsd_db *) kmem_alloc(newlen, KMEM_NOSLEEP);
+#ifdef __osf__
+ db = (struct bsd_db *) ALLOC_SLEEP(newlen);
+#else
+ db = (struct bsd_db *) ALLOC_NOSLEEP(newlen);
+#endif
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);
+#ifdef __osf__
+ db->lens = (u_short *) ALLOC_SLEEP((maxmaxcode+1) * sizeof(db->lens[0]));
+#else
+ db->lens = (u_short *) ALLOC_NOSLEEP((maxmaxcode+1) * sizeof(db->lens[0]));
+#endif
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 < CILEN_BSD_COMPRESS
+ || options[0] != CI_BSD_COMPRESS || options[1] != CILEN_BSD_COMPRESS
|| 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)
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 (ent < 0x21 || ent > 0xf9)
return;
- db->incomp_count++;
db->seqno++;
ilen = 1; /* count the protocol as 1 byte */
rptr += PPP_HDRLEN;
db->in_count += ilen;
(void)bsd_check(db);
- ++db->comp_count;
- db->comp_bytes += bitno / 8;
++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)
/*
* 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
break;
rptr = cmsg->b_rptr;
len = cmsg->b_wptr - rptr;
+ 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. */
*dmpp = mret;
return DECOMP_OK;
}
+#endif /* DO_BSD_COMPRESS */