/* Copy an RDATA, using compression pointers where RFC1035 permits.
*/
static int
rdcpy(ns_newmsg *handle, ns_type type, const u_char *rdata, size_t rdlen) {
ns_msg *msg = &handle->msg;
u_char *p = (u_char *) (unsigned long) msg->_msg_ptr;
u_char *t = p + NS_INT16SZ;
u_char *s = t;
int n;
switch (type) {
case ns_t_soa:
/* MNAME. */
n = ns_name_pack(rdata, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (ns_name_skip(&rdata, msg->_eom) < 0)
return (-1);
/* ANAME. */
n = ns_name_pack(rdata, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (ns_name_skip(&rdata, msg->_eom) < 0)
return (-1);
/* Serial, Refresh, Retry, Expiry, and Minimum. */
if ((msg->_eom - t) < (NS_INT32SZ * 5)) {
errno = EMSGSIZE;
return (-1);
}
memcpy(t, rdata, NS_INT32SZ * 5);
t += (NS_INT32SZ * 5);
break;
case ns_t_ptr:
case ns_t_cname:
case ns_t_ns:
/* PTRDNAME, CNAME, or NSDNAME. */
n = ns_name_pack(rdata, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
break;
default:
memcpy(t, rdata, rdlen);
t += rdlen;
}
NS_PUT16(t - s, p);
msg->_msg_ptr = t;
return (0);
}
/* Add a question (or zone, if it's an update) to a "newmsg" object.
*/
int
ns_newmsg_q(ns_newmsg *handle, ns_nname_ct qname,
ns_type qtype, ns_class qclass)
{
ns_msg *msg = &handle->msg;
u_char *t;
int n;
if (msg->_sect != ns_s_qd) {
errno = ENODEV;
return (-1);
}
t = (u_char *) (unsigned long) msg->_msg_ptr;
if (msg->_rrnum == 0)
msg->_sections[ns_s_qd] = t;
n = ns_name_pack(qname, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (t + QFIXEDSZ >= msg->_eom) {
errno = EMSGSIZE;
return (-1);
}
NS_PUT16(qtype, t);
NS_PUT16(qclass, t);
msg->_msg_ptr = t;
msg->_counts[ns_s_qd] = ++msg->_rrnum;
return (0);
}
/* Add an RR to a "newmsg" object.
*/
int
ns_newmsg_rr(ns_newmsg *handle, ns_sect sect,
ns_nname_ct name, ns_type type,
ns_class rr_class, u_int32_t ttl,
u_int16_t rdlen, const u_char *rdata)
{
ns_msg *msg = &handle->msg;
u_char *t;
int n;
if (sect < msg->_sect) {
errno = ENODEV;
return (-1);
}
t = (u_char *) (unsigned long) msg->_msg_ptr;
if (sect > msg->_sect) {
msg->_sect = sect;
msg->_sections[sect] = t;
msg->_rrnum = 0;
}
n = ns_name_pack(name, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (t + RRFIXEDSZ + rdlen >= msg->_eom) {
errno = EMSGSIZE;
return (-1);
}
NS_PUT16(type, t);
NS_PUT16(rr_class, t);
NS_PUT32(ttl, t);
msg->_msg_ptr = t;
if (rdcpy(handle, type, rdata, rdlen) < 0)
return (-1);
msg->_counts[sect] = ++msg->_rrnum;
return (0);
}
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, *eob;
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);
cp = msg + *msglen;
eob = msg + msgsize;
/* Name. */
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;
/* Type, class, ttl, length (not filled in yet). */
BOUNDS_CHECK(cp, INT16SZ + INT16SZ + INT32SZ + INT16SZ);
PUTSHORT(ns_t_tsig, cp);
PUTSHORT(ns_c_any, cp);
PUTLONG(0, cp); /*%< TTL */
lenp = cp;
cp += 2;
/* Alg. */
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;
/* Time. */
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);
/* Compute the signature. */
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);
/* Digest the query signature, if this is a response. */
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);
}
/* Digest the message. */
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, msg, *msglen,
NULL, 0);
/* Digest the key name. */
n = ns_name_ntol(name, buf, sizeof(buf));
INSIST(n > 0);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0);
/* Digest the class and TTL. */
cp2 = buf;
PUTSHORT(ns_c_any, cp2);
PUTLONG(0, cp2);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, cp2-buf,
NULL, 0);
/* Digest the algorithm. */
n = ns_name_ntol(alg, buf, sizeof(buf));
INSIST(n > 0);
dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0);
/* Digest the time signed, fudge, error, and other data */
cp2 = buf;
PUTSHORT(0, cp2); /*%< Top 16 bits of time */
if (error != ns_r_badtime)
PUTLONG(timesigned, cp2);
else
PUTLONG(in_timesigned, cp2);
PUTSHORT(NS_TSIG_FUDGE, cp2);
PUTSHORT(error, cp2); /*%< Error */
if (error != ns_r_badtime)
PUTSHORT(0, cp2); /*%< Other data length */
else {
PUTSHORT(INT16SZ+INT32SZ, cp2); /*%< Other data length */
PUTSHORT(0, cp2); /*%< Top 16 bits of time */
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;
/* Add the signature. */
BOUNDS_CHECK(cp, INT16SZ + (*siglen));
PUTSHORT(*siglen, cp);
memcpy(cp, sig, *siglen);
cp += (*siglen);
/* The original message ID & error. */
BOUNDS_CHECK(cp, INT16SZ + INT16SZ);
PUTSHORT(ntohs(hp->id), cp); /*%< already in network order */
PUTSHORT(error, cp);
/* Other data. */
BOUNDS_CHECK(cp, INT16SZ);
if (error != ns_r_badtime)
PUTSHORT(0, cp); /*%< Other data length */
else {
PUTSHORT(INT16SZ+INT32SZ, cp); /*%< Other data length */
BOUNDS_CHECK(cp, INT32SZ+INT16SZ);
PUTSHORT(0, cp); /*%< Top 16 bits of time */
PUTLONG(timesigned, cp);
}
/* Go back and fill in the length. */
PUTSHORT(cp - lenp - INT16SZ, lenp);
hp->arcount = htons(ntohs(hp->arcount) + 1);
*msglen = (cp - msg);
return (0);
}
