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/*
* Copyright (c) 1995, 1996, 1997
* The Regents of the University of California. 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, (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, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may 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.
*
* Initial contribution from John Hawkinson (jhawk@mit.edu).
*/
/* \summary: Kerberos printer */
#include <config.h>
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "extract.h"
/*
* Kerberos 4:
*
* Athena Technical Plan
* Section E.2.1
* Kerberos Authentication and Authorization System
* by S. P. Miller, B. C. Neuman, J. I. Schiller, and J. H. Saltzer
*
* https://web.mit.edu/Saltzer/www/publications/athenaplan/e.2.1.pdf
*
* 7. Appendix I Design Specifications
*
* Kerberos 5:
*
* RFC 1510, RFC 2630, etc.
*/
static const u_char *c_print(netdissect_options *, const u_char *, const u_char *);
static const u_char *krb4_print_hdr(netdissect_options *, const u_char *);
static void krb4_print(netdissect_options *, const u_char *);
#define AUTH_MSG_KDC_REQUEST 1<<1
#define AUTH_MSG_KDC_REPLY 2<<1
#define AUTH_MSG_APPL_REQUEST 3<<1
#define AUTH_MSG_APPL_REQUEST_MUTUAL 4<<1
#define AUTH_MSG_ERR_REPLY 5<<1
#define AUTH_MSG_PRIVATE 6<<1
#define AUTH_MSG_SAFE 7<<1
#define AUTH_MSG_APPL_ERR 8<<1
#define AUTH_MSG_DIE 63<<1
#define KERB_ERR_OK 0
#define KERB_ERR_NAME_EXP 1
#define KERB_ERR_SERVICE_EXP 2
#define KERB_ERR_AUTH_EXP 3
#define KERB_ERR_PKT_VER 4
#define KERB_ERR_NAME_MAST_KEY_VER 5
#define KERB_ERR_SERV_MAST_KEY_VER 6
#define KERB_ERR_BYTE_ORDER 7
#define KERB_ERR_PRINCIPAL_UNKNOWN 8
#define KERB_ERR_PRINCIPAL_NOT_UNIQUE 9
#define KERB_ERR_NULL_KEY 10
struct krb {
nd_uint8_t pvno; /* Protocol Version */
nd_uint8_t type; /* Type+B */
};
static const struct tok type2str[] = {
{ AUTH_MSG_KDC_REQUEST, "KDC_REQUEST" },
{ AUTH_MSG_KDC_REPLY, "KDC_REPLY" },
{ AUTH_MSG_APPL_REQUEST, "APPL_REQUEST" },
{ AUTH_MSG_APPL_REQUEST_MUTUAL, "APPL_REQUEST_MUTUAL" },
{ AUTH_MSG_ERR_REPLY, "ERR_REPLY" },
{ AUTH_MSG_PRIVATE, "PRIVATE" },
{ AUTH_MSG_SAFE, "SAFE" },
{ AUTH_MSG_APPL_ERR, "APPL_ERR" },
{ AUTH_MSG_DIE, "DIE" },
{ 0, NULL }
};
static const struct tok kerr2str[] = {
{ KERB_ERR_OK, "OK" },
{ KERB_ERR_NAME_EXP, "NAME_EXP" },
{ KERB_ERR_SERVICE_EXP, "SERVICE_EXP" },
{ KERB_ERR_AUTH_EXP, "AUTH_EXP" },
{ KERB_ERR_PKT_VER, "PKT_VER" },
{ KERB_ERR_NAME_MAST_KEY_VER, "NAME_MAST_KEY_VER" },
{ KERB_ERR_SERV_MAST_KEY_VER, "SERV_MAST_KEY_VER" },
{ KERB_ERR_BYTE_ORDER, "BYTE_ORDER" },
{ KERB_ERR_PRINCIPAL_UNKNOWN, "PRINCIPAL_UNKNOWN" },
{ KERB_ERR_PRINCIPAL_NOT_UNIQUE,"PRINCIPAL_NOT_UNIQUE" },
{ KERB_ERR_NULL_KEY, "NULL_KEY"},
{ 0, NULL}
};
static const u_char *
c_print(netdissect_options *ndo,
const u_char *s, const u_char *ep)
{
u_char c;
int flag;
flag = 1;
while (s < ep) {
c = GET_U_1(s);
s++;
if (c == '\0') {
flag = 0;
break;
}
fn_print_char(ndo, c);
}
if (flag)
return NULL;
return (s);
}
static const u_char *
krb4_print_hdr(netdissect_options *ndo,
const u_char *cp)
{
cp += 2;
#define PRINT if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
PRINT;
ND_PRINT(".");
PRINT;
ND_PRINT("@");
PRINT;
return (cp);
trunc:
nd_print_trunc(ndo);
return (NULL);
#undef PRINT
}
static void
krb4_print(netdissect_options *ndo,
const u_char *cp)
{
const struct krb *kp;
u_char type;
u_short len;
#define PRINT if ((cp = c_print(ndo, cp, ndo->ndo_snapend)) == NULL) goto trunc
/* True if struct krb is little endian */
#define IS_LENDIAN(kp) ((GET_U_1((kp)->type) & 0x01) != 0)
#define KTOHSP(kp, cp) (IS_LENDIAN(kp) ? GET_LE_U_2(cp) : GET_BE_U_2(cp))
kp = (const struct krb *)cp;
type = GET_U_1(kp->type) & (0xFF << 1);
ND_PRINT(" %s %s: ",
IS_LENDIAN(kp) ? "le" : "be", tok2str(type2str, NULL, type));
switch (type) {
case AUTH_MSG_KDC_REQUEST:
if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
return;
cp += 4; /* ctime */
ND_PRINT(" %umin ", GET_U_1(cp) * 5);
cp++;
PRINT;
ND_PRINT(".");
PRINT;
break;
case AUTH_MSG_APPL_REQUEST:
cp += 2;
ND_PRINT("v%u ", GET_U_1(cp));
cp++;
PRINT;
ND_PRINT(" (%u)", GET_U_1(cp));
cp++;
ND_PRINT(" (%u)", GET_U_1(cp));
break;
case AUTH_MSG_KDC_REPLY:
if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
return;
cp += 10; /* timestamp + n + exp + kvno */
len = KTOHSP(kp, cp);
ND_PRINT(" (%u)", len);
break;
case AUTH_MSG_ERR_REPLY:
if ((cp = krb4_print_hdr(ndo, cp)) == NULL)
return;
cp += 4; /* timestamp */
ND_PRINT(" %s ", tok2str(kerr2str, NULL, KTOHSP(kp, cp)));
cp += 4;
PRINT;
break;
default:
ND_PRINT("(unknown)");
break;
}
return;
trunc:
nd_print_trunc(ndo);
}
void
krb_print(netdissect_options *ndo,
const u_char *dat)
{
const struct krb *kp;
ndo->ndo_protocol = "kerberos";
nd_print_protocol(ndo);
kp = (const struct krb *)dat;
switch (GET_U_1(kp->pvno)) {
case 1:
case 2:
case 3:
ND_PRINT(" v%u", GET_U_1(kp->pvno));
break;
case 4:
ND_PRINT(" v%u", GET_U_1(kp->pvno));
krb4_print(ndo, (const u_char *)kp);
break;
case 106:
case 107:
ND_PRINT(" v5");
/* Decode ASN.1 here "someday" */
break;
}
}
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