DST_KEY *
dst_dnskey_to_key(const char *in_name, const u_char *rdata, const int len)
{
DST_KEY *key_st;
int alg ;
int start = DST_KEY_START;
if (rdata == NULL || len <= DST_KEY_ALG) /*%< no data */
return (NULL);
alg = (u_int8_t) rdata[DST_KEY_ALG];
if (!dst_check_algorithm(alg)) { /*%< make sure alg is available */
EREPORT(("dst_dnskey_to_key(): Algorithm %d not suppored\n",
alg));
return (NULL);
}
if (in_name == NULL)
return (NULL);
if ((key_st = dst_s_get_key_struct(in_name, alg, 0, 0, 0)) == NULL)
return (NULL);
key_st->dk_id = dst_s_dns_key_id(rdata, len);
key_st->dk_flags = dst_s_get_int16(rdata);
key_st->dk_proto = (u_int16_t) rdata[DST_KEY_PROT];
if (key_st->dk_flags & DST_EXTEND_FLAG) {
u_int32_t ext_flags;
ext_flags = (u_int32_t) dst_s_get_int16(&rdata[DST_EXT_FLAG]);
key_st->dk_flags = key_st->dk_flags | (ext_flags << 16);
start += 2;
}
/*
* now point to the begining of the data representing the encoding
* of the key
*/
if (key_st->dk_func && key_st->dk_func->from_dns_key) {
if (key_st->dk_func->from_dns_key(key_st, &rdata[start],
len - start) > 0)
return (key_st);
} else
EREPORT(("dst_dnskey_to_public_key(): unsuppored alg %d\n",
alg));
SAFE_FREE(key_st);
return (key_st);
}
/*
* dst_s_dns_key_id() Function to calculated DNSSEC footprint from KEY record
* rdata (all of record)
* Input:
* dns_key_rdata: the raw data in wire format
* rdata_len: the size of the input data
* Output:
* the key footprint/id calculated from the key data
*/
u_int16_t
dst_s_dns_key_id(const u_char *dns_key_rdata, const unsigned rdata_len)
{
unsigned key_data = 4;
if (!dns_key_rdata || (rdata_len < key_data))
return 0;
/* check the extended parameters bit in the DNS Key RR flags */
if (dst_s_get_int16(dns_key_rdata) & DST_EXTEND_FLAG)
key_data += 2;
/* compute id */
if (dns_key_rdata[3] == KEY_RSA) /* Algorithm RSA */
return dst_s_get_int16((const u_char *)
&dns_key_rdata[rdata_len - 3]);
else
/* compute a checksum on the key part of the key rr */
return dst_s_id_calc(&dns_key_rdata[key_data],
(rdata_len - key_data));
}
/*%
* dst_s_dns_key_id() Function to calculate DNSSEC footprint from KEY record
* rdata
* Input:
* dns_key_rdata: the raw data in wire format
* rdata_len: the size of the input data
* Output:
* the key footprint/id calculated from the key data
*/
u_int16_t
dst_s_dns_key_id(const u_char *dns_key_rdata, const int rdata_len)
{
if (!dns_key_rdata)
return 0;
/* compute id */
if (dns_key_rdata[3] == KEY_RSA) /*%< Algorithm RSA */
return dst_s_get_int16((const u_char *)
&dns_key_rdata[rdata_len - 3]);
else if (dns_key_rdata[3] == KEY_HMAC_MD5)
/* compatibility */
return 0;
else
/* compute a checksum on the key part of the key rr */
return dst_s_id_calc(dns_key_rdata, rdata_len);
}
