/*
* Decode and print Zephyr packets.
*
* http://web.mit.edu/zephyr/doc/protocol
*
* Copyright (c) 2001 Nickolai Zeldovich <kolya@MIT.EDU>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code
* distributions retain the above copyright notice and this paragraph
* in its entirety, and (2) distributions including binary code include
* the above copyright notice and this paragraph in its entirety in
* the documentation or other materials provided with the distribution.
* The name of the author(s) may not be used to endorse or promote
* products derived from this software without specific prior written
* permission. THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE.
*/
/* \summary: Zephyr printer */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <netdissect-stdinc.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "netdissect.h"
struct z_packet {
const char *version;
int numfields;
int kind;
const char *uid;
int port;
int auth;
int authlen;
const char *authdata;
const char *class;
const char *inst;
const char *opcode;
const char *sender;
const char *recipient;
const char *format;
int cksum;
int multi;
const char *multi_uid;
/* Other fields follow here.. */
};
enum z_packet_type {
Z_PACKET_UNSAFE = 0,
Z_PACKET_UNACKED,
Z_PACKET_ACKED,
Z_PACKET_HMACK,
Z_PACKET_HMCTL,
Z_PACKET_SERVACK,
Z_PACKET_SERVNAK,
Z_PACKET_CLIENTACK,
Z_PACKET_STAT
};
static const struct tok z_types[] = {
{ Z_PACKET_UNSAFE, "unsafe" },
{ Z_PACKET_UNACKED, "unacked" },
{ Z_PACKET_ACKED, "acked" },
{ Z_PACKET_HMACK, "hm-ack" },
{ Z_PACKET_HMCTL, "hm-ctl" },
{ Z_PACKET_SERVACK, "serv-ack" },
{ Z_PACKET_SERVNAK, "serv-nak" },
{ Z_PACKET_CLIENTACK, "client-ack" },
{ Z_PACKET_STAT, "stat" },
{ 0, NULL }
};
static char z_buf[256];
static const char *
parse_field(netdissect_options *ndo, const char **pptr, int *len, int *truncated)
{
const char *s;
/* Start of string */
s = *pptr;
/* Scan for the NUL terminator */
for (;;) {
if (*len == 0) {
/* Ran out of packet data without finding it */
return NULL;
}
if (!ND_TTEST(**pptr)) {
/* Ran out of captured data without finding it */
*truncated = 1;
return NULL;
}
if (**pptr == '\0') {
/* Found it */
break;
}
/* Keep scanning */
(*pptr)++;
(*len)--;
}
/* Skip the NUL terminator */
(*pptr)++;
(*len)--;
return s;
}
static const char *
z_triple(const char *class, const char *inst, const char *recipient)
{
if (!*recipient)
recipient = "*";
snprintf(z_buf, sizeof(z_buf), "<%s,%s,%s>", class, inst, recipient);
z_buf[sizeof(z_buf)-1] = '\0';
return z_buf;
}
static const char *
str_to_lower(const char *string)
{
char *zb_string;
strncpy(z_buf, string, sizeof(z_buf));
z_buf[sizeof(z_buf)-1] = '\0';
zb_string = z_buf;
while (*zb_string) {
*zb_string = tolower((unsigned char)(*zb_string));
zb_string++;
}
return z_buf;
}
void
zephyr_print(netdissect_options *ndo, const u_char *cp, int length)
{
struct z_packet z;
const char *parse = (const char *) cp;
int parselen = length;
const char *s;
int lose = 0;
int truncated = 0;
/* squelch compiler warnings */
z.kind = 0;
z.class = 0;
z.inst = 0;
z.opcode = 0;
z.sender = 0;
z.recipient = 0;
#define PARSE_STRING \
s = parse_field(ndo, &parse, &parselen, &truncated); \
if (truncated) goto trunc; \
if (!s) lose = 1;
#define PARSE_FIELD_INT(field) \
PARSE_STRING \
if (!lose) field = strtol(s, 0, 16);
#define PARSE_FIELD_STR(field) \
PARSE_STRING \
if (!lose) field = s;
PARSE_FIELD_STR(z.version);
if (lose) return;
if (strncmp(z.version, "ZEPH", 4))
return;
PARSE_FIELD_INT(z.numfields);
PARSE_FIELD_INT(z.kind);
PARSE_FIELD_STR(z.uid);
PARSE_FIELD_INT(z.port);
PARSE_FIELD_INT(z.auth);
PARSE_FIELD_INT(z.authlen);
PARSE_FIELD_STR(z.authdata);
PARSE_FIELD_STR(z.class);
PARSE_FIELD_STR(z.inst);
PARSE_FIELD_STR(z.opcode);
PARSE_FIELD_STR(z.sender);
PARSE_FIELD_STR(z.recipient);
PARSE_FIELD_STR(z.format);
PARSE_FIELD_INT(z.cksum);
PARSE_FIELD_INT(z.multi);
PARSE_FIELD_STR(z.multi_uid);
if (lose)
goto trunc;
ND_PRINT((ndo, " zephyr"));
if (strncmp(z.version+4, "0.2", 3)) {
ND_PRINT((ndo, " v%s", z.version+4));
return;
}
ND_PRINT((ndo, " %s", tok2str(z_types, "type %d", z.kind)));
if (z.kind == Z_PACKET_SERVACK) {
/* Initialization to silence warnings */
const char *ackdata = NULL;
PARSE_FIELD_STR(ackdata);
if (!lose && strcmp(ackdata, "SENT"))
ND_PRINT((ndo, "/%s", str_to_lower(ackdata)));
}
if (*z.sender) ND_PRINT((ndo, " %s", z.sender));
if (!strcmp(z.class, "USER_LOCATE")) {
if (!strcmp(z.opcode, "USER_HIDE"))
ND_PRINT((ndo, " hide"));
else if (!strcmp(z.opcode, "USER_UNHIDE"))
ND_PRINT((ndo, " unhide"));
else
ND_PRINT((ndo, " locate %s", z.inst));
return;
}
if (!strcmp(z.class, "ZEPHYR_ADMIN")) {
ND_PRINT((ndo, " zephyr-admin %s", str_to_lower(z.opcode)));
return;
}
if (!strcmp(z.class, "ZEPHYR_CTL")) {
if (!strcmp(z.inst, "CLIENT")) {
if (!strcmp(z.opcode, "SUBSCRIBE") ||
!strcmp(z.opcode, "SUBSCRIBE_NODEFS") ||
!strcmp(z.opcode, "UNSUBSCRIBE")) {
ND_PRINT((ndo, " %ssub%s", strcmp(z.opcode, "SUBSCRIBE") ? "un" : "",
strcmp(z.opcode, "SUBSCRIBE_NODEFS") ? "" :
"-nodefs"));
if (z.kind != Z_PACKET_SERVACK) {
/* Initialization to silence warnings */
const char *c = NULL, *i = NULL, *r = NULL;
PARSE_FIELD_STR(c);
PARSE_FIELD_STR(i);
PARSE_FIELD_STR(r);
if (!lose) ND_PRINT((ndo, " %s", z_triple(c, i, r)));
}
return;
}
if (!strcmp(z.opcode, "GIMME")) {
ND_PRINT((ndo, " ret"));
return;
}
if (!strcmp(z.opcode, "GIMMEDEFS")) {
ND_PRINT((ndo, " gimme-defs"));
return;
}
if (!strcmp(z.opcode, "CLEARSUB")) {
ND_PRINT((ndo, " clear-subs"));
return;
}
ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
return;
}
if (!strcmp(z.inst, "HM")) {
ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
return;
}
if (!strcmp(z.inst, "REALM")) {
if (!strcmp(z.opcode, "ADD_SUBSCRIBE"))
ND_PRINT((ndo, " realm add-subs"));
if (!strcmp(z.opcode, "REQ_SUBSCRIBE"))
ND_PRINT((ndo, " realm req-subs"));
if (!strcmp(z.opcode, "RLM_SUBSCRIBE"))
ND_PRINT((ndo, " realm rlm-sub"));
if (!strcmp(z.opcode, "RLM_UNSUBSCRIBE"))
ND_PRINT((ndo, " realm rlm-unsub"));
return;
}
}
if (!strcmp(z.class, "HM_CTL")) {
ND_PRINT((ndo, " hm_ctl %s", str_to_lower(z.inst)));
ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
return;
}
if (!strcmp(z.class, "HM_STAT")) {
if (!strcmp(z.inst, "HMST_CLIENT") && !strcmp(z.opcode, "GIMMESTATS")) {
ND_PRINT((ndo, " get-client-stats"));
return;
}
}
if (!strcmp(z.class, "WG_CTL")) {
ND_PRINT((ndo, " wg_ctl %s", str_to_lower(z.inst)));
ND_PRINT((ndo, " %s", str_to_lower(z.opcode)));
return;
}
if (!strcmp(z.class, "LOGIN")) {
if (!strcmp(z.opcode, "USER_FLUSH")) {
ND_PRINT((ndo, " flush_locs"));
return;
}
if (!strcmp(z.opcode, "NONE") ||
!strcmp(z.opcode, "OPSTAFF") ||
!strcmp(z.opcode, "REALM-VISIBLE") ||
!strcmp(z.opcode, "REALM-ANNOUNCED") ||
!strcmp(z.opcode, "NET-VISIBLE") ||
!strcmp(z.opcode, "NET-ANNOUNCED")) {
ND_PRINT((ndo, " set-exposure %s", str_to_lower(z.opcode)));
return;
}
}
if (!*z.recipient)
z.recipient = "*";
ND_PRINT((ndo, " to %s", z_triple(z.class, z.inst, z.recipient)));
if (*z.opcode)
ND_PRINT((ndo, " op %s", z.opcode));
return;
trunc:
ND_PRINT((ndo, " [|zephyr] (%d)", length));
return;
}