#ifndef lint
static const char rcsid[] = "$Id: ns_sign.c,v 1.1.2.2.4.1 2004/03/09 08:33:45 marka Exp $";
#endif
#include "port_before.h"
#include "fd_setsize.h"
#include <sys/types.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <errno.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <isc/dst.h>
#include <isc/assertions.h>
#include "port_after.h"
#define BOUNDS_CHECK(ptr, count) \
do { \
if ((ptr) + (count) > eob) { \
errno = EMSGSIZE; \
return(NS_TSIG_ERROR_NO_SPACE); \
} \
} while (0)
int
ns_sign(u_char *msg, int *msglen, int msgsize, int error, void *k,
const u_char *querysig, int querysiglen, u_char *sig, int *siglen,
time_t in_timesigned)
{
return(ns_sign2(msg, msglen, msgsize, error, k,
querysig, querysiglen, sig, siglen,
in_timesigned, NULL, NULL));
}
int
ns_sign2(u_char *msg, int *msglen, int msgsize, int error, void *k,
const u_char *querysig, int querysiglen, u_char *sig, int *siglen,
time_t in_timesigned, u_char **dnptrs, u_char **lastdnptr)
{
HEADER *hp = (HEADER *)msg;
DST_KEY *key = (DST_KEY *)k;
u_char *cp = msg + *msglen, *eob = msg + msgsize;
u_char *lenp;
u_char *alg;
int n;
time_t timesigned;
u_char name[NS_MAXCDNAME];
dst_init();
if (msg == NULL || msglen == NULL || sig == NULL || siglen == NULL)
return (-1);
if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) {
n = ns_name_pton(key->dk_key_name, name, sizeof name);
if (n != -1)
n = ns_name_pack(name, cp, eob - cp,
(const u_char **)dnptrs,
(const u_char **)lastdnptr);
} else {
n = ns_name_pton("", name, sizeof name);
if (n != -1)
n = ns_name_pack(name, cp, eob - cp, NULL, NULL);
}
if (n < 0)
return (NS_TSIG_ERROR_NO_SPACE);
cp += n;
BOUNDS_CHECK(cp, INT16SZ + INT16SZ + INT32SZ + INT16SZ);
PUTSHORT(ns_t_tsig, cp);
PUTSHORT(ns_c_any, cp);
PUTLONG(0, cp);
lenp = cp;
cp += 2;
if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) {
if (key->dk_alg != KEY_HMAC_MD5)
return (-ns_r_badkey);
n = dn_comp(NS_TSIG_ALG_HMAC_MD5, cp, eob - cp, NULL, NULL);
}
else
n = dn_comp("", cp, eob - cp, NULL, NULL);
if (n < 0)
return (NS_TSIG_ERROR_NO_SPACE);
alg = cp;
cp += n;
BOUNDS_CHECK(cp, INT16SZ + INT32SZ + INT16SZ);
PUTSHORT(0, cp);
timesigned = time(NULL);
if (error != ns_r_badtime)
PUTLONG(timesigned, cp);
else
PUTLONG(in_timesigned, cp);
PUTSHORT(NS_TSIG_FUDGE, cp);
if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) {
void *ctx;
u_char buf[NS_MAXCDNAME], *cp2;
int n;
dst_sign_data(SIG_MODE_INIT, key, &ctx, NULL, 0, NULL, 0);
if (querysiglen > 0 && querysig != NULL) {
u_int16_t len_n = htons(querysiglen);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx,
(u_char *)&len_n, INT16SZ, NULL, 0);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx,
querysig, querysiglen, NULL, 0);
}
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, msg, *msglen,
NULL, 0);
n = ns_name_ntol(name, buf, sizeof(buf));
INSIST(n > 0);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0);
cp2 = buf;
PUTSHORT(ns_c_any, cp2);
PUTLONG(0, cp2);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, cp2-buf,
NULL, 0);
n = ns_name_ntol(alg, buf, sizeof(buf));
INSIST(n > 0);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0);
cp2 = buf;
PUTSHORT(0, cp2);
if (error != ns_r_badtime)
PUTLONG(timesigned, cp2);
else
PUTLONG(in_timesigned, cp2);
PUTSHORT(NS_TSIG_FUDGE, cp2);
PUTSHORT(error, cp2);
if (error != ns_r_badtime)
PUTSHORT(0, cp2);
else {
PUTSHORT(INT16SZ+INT32SZ, cp2);
PUTSHORT(0, cp2);
PUTLONG(timesigned, cp2);
}
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, cp2-buf,
NULL, 0);
n = dst_sign_data(SIG_MODE_FINAL, key, &ctx, NULL, 0,
sig, *siglen);
if (n < 0)
return (-ns_r_badkey);
*siglen = n;
} else
*siglen = 0;
BOUNDS_CHECK(cp, INT16SZ + (*siglen));
PUTSHORT(*siglen, cp);
memcpy(cp, sig, *siglen);
cp += (*siglen);
BOUNDS_CHECK(cp, INT16SZ + INT16SZ);
PUTSHORT(ntohs(hp->id), cp);
PUTSHORT(error, cp);
BOUNDS_CHECK(cp, INT16SZ);
if (error != ns_r_badtime)
PUTSHORT(0, cp);
else {
PUTSHORT(INT16SZ+INT32SZ, cp);
BOUNDS_CHECK(cp, INT32SZ+INT16SZ);
PUTSHORT(0, cp);
PUTLONG(timesigned, cp);
}
PUTSHORT(cp - lenp - INT16SZ, lenp);
hp->arcount = htons(ntohs(hp->arcount) + 1);
*msglen = (cp - msg);
return (0);
}
int
ns_sign_tcp_init(void *k, const u_char *querysig, int querysiglen,
ns_tcp_tsig_state *state)
{
dst_init();
if (state == NULL || k == NULL || querysig == NULL || querysiglen < 0)
return (-1);
state->counter = -1;
state->key = k;
if (state->key->dk_alg != KEY_HMAC_MD5)
return (-ns_r_badkey);
if (querysiglen > (int)sizeof(state->sig))
return (-1);
memcpy(state->sig, querysig, querysiglen);
state->siglen = querysiglen;
return (0);
}
int
ns_sign_tcp(u_char *msg, int *msglen, int msgsize, int error,
ns_tcp_tsig_state *state, int done)
{
return (ns_sign_tcp2(msg, msglen, msgsize, error, state,
done, NULL, NULL));
}
int
ns_sign_tcp2(u_char *msg, int *msglen, int msgsize, int error,
ns_tcp_tsig_state *state, int done,
u_char **dnptrs, u_char **lastdnptr)
{
u_char *cp, *eob, *lenp;
u_char buf[MAXDNAME], *cp2;
HEADER *hp = (HEADER *)msg;
time_t timesigned;
int n;
if (msg == NULL || msglen == NULL || state == NULL)
return (-1);
state->counter++;
if (state->counter == 0)
return (ns_sign2(msg, msglen, msgsize, error, state->key,
state->sig, state->siglen,
state->sig, &state->siglen, 0,
dnptrs, lastdnptr));
if (state->siglen > 0) {
u_int16_t siglen_n = htons(state->siglen);
dst_sign_data(SIG_MODE_INIT, state->key, &state->ctx,
NULL, 0, NULL, 0);
dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx,
(u_char *)&siglen_n, INT16SZ, NULL, 0);
dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx,
state->sig, state->siglen, NULL, 0);
state->siglen = 0;
}
dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx, msg, *msglen,
NULL, 0);
if (done == 0 && (state->counter % 100 != 0))
return (0);
cp = msg + *msglen;
eob = msg + msgsize;
n = dn_comp(state->key->dk_key_name, cp, eob - cp, dnptrs, lastdnptr);
if (n < 0)
return (NS_TSIG_ERROR_NO_SPACE);
cp += n;
BOUNDS_CHECK(cp, INT16SZ + INT16SZ + INT32SZ + INT16SZ);
PUTSHORT(ns_t_tsig, cp);
PUTSHORT(ns_c_any, cp);
PUTLONG(0, cp);
lenp = cp;
cp += 2;
n = dn_comp(NS_TSIG_ALG_HMAC_MD5, cp, eob - cp, NULL, NULL);
if (n < 0)
return (NS_TSIG_ERROR_NO_SPACE);
cp += n;
BOUNDS_CHECK(cp, INT16SZ + INT32SZ + INT16SZ);
PUTSHORT(0, cp);
timesigned = time(NULL);
PUTLONG(timesigned, cp);
PUTSHORT(NS_TSIG_FUDGE, cp);
cp2 = buf;
PUTSHORT(0, cp2);
PUTLONG(timesigned, cp2);
PUTSHORT(NS_TSIG_FUDGE, cp2);
dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx,
buf, cp2 - buf, NULL, 0);
n = dst_sign_data(SIG_MODE_FINAL, state->key, &state->ctx, NULL, 0,
state->sig, sizeof(state->sig));
if (n < 0)
return (-ns_r_badkey);
state->siglen = n;
BOUNDS_CHECK(cp, INT16SZ + state->siglen);
PUTSHORT(state->siglen, cp);
memcpy(cp, state->sig, state->siglen);
cp += state->siglen;
BOUNDS_CHECK(cp, INT16SZ + INT16SZ);
PUTSHORT(ntohs(hp->id), cp);
PUTSHORT(error, cp);
BOUNDS_CHECK(cp, INT16SZ);
PUTSHORT(0, cp);
PUTSHORT(cp - lenp - INT16SZ, lenp);
hp->arcount = htons(ntohs(hp->arcount) + 1);
*msglen = (cp - msg);
return (0);
}