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#include "includes.h"
#include "dbutil.h"
#include "crypto_desc.h"
#include "ecc.h"
#ifdef DROPBEAR_ECDSA
ecc_key *gen_ecdsa_priv_key(unsigned int bit_size) {
const ltc_ecc_set_type *dp = NULL; // curve domain parameters
// TODO: use raw bytes for the dp rather than the hex strings in libtomcrypt's ecc.c
switch (bit_size) {
#ifdef DROPBEAR_ECC_256
case 256:
dp = ecc_curve_nistp256.dp;
break;
#endif
#ifdef DROPBEAR_ECC_384
case 384:
dp = ecc_curve_nistp384.dp;
break;
#endif
#ifdef DROPBEAR_ECC_521
case 521:
dp = ecc_curve_nistp521.dp;
break;
#endif
}
if (!dp) {
dropbear_exit("Key size %d isn't valid. Try "
#ifdef DROPBEAR_ECC_256
"256 "
#endif
#ifdef DROPBEAR_ECC_384
"384 "
#endif
#ifdef DROPBEAR_ECC_521
"521 "
#endif
, bit_size);
}
ecc_key *new_key = m_malloc(sizeof(*new_key));
if (ecc_make_key_ex(NULL, dropbear_ltc_prng, new_key, dp) != CRYPT_OK) {
dropbear_exit("ECC error");
}
return new_key;
}
ecc_key *buf_get_ecdsa_pub_key(buffer* buf) {
unsigned char *key_ident = NULL, *identifier = NULL;
unsigned int key_ident_len, identifier_len;
buffer *q_buf = NULL;
struct dropbear_ecc_curve **curve;
ecc_key *new_key = NULL;
// string "ecdsa-sha2-[identifier]"
key_ident = buf_getstring(buf, &key_ident_len);
// string "ecdsa-sha2-[identifier]"
identifier = buf_getstring(buf, &identifier_len);
if (key_ident_len != identifier_len + strlen("ecdsa-sha2-")) {
TRACE(("Bad identifier lengths"))
goto out;
}
if (memcmp(&key_ident[strlen("ecdsa-sha2-")], identifier, identifier_len) != 0) {
TRACE(("mismatching identifiers"))
goto out;
}
for (curve = dropbear_ecc_curves; *curve; curve++) {
if (memcmp(identifier, (*curve)->name, strlen((*curve)->name)) == 0) {
break;
}
}
if (!*curve) {
TRACE(("couldn't match ecc curve"))
goto out;
}
// string Q
q_buf = buf_getstringbuf(buf);
new_key = buf_get_ecc_raw_pubkey(q_buf, *curve);
out:
if (key_ident) {
m_free(key_ident);
}
if (identifier) {
m_free(identifier);
}
if (q_buf) {
buf_free(q_buf);
q_buf = NULL;
}
TRACE(("leave buf_get_ecdsa_pub_key"))
return new_key;
}
#endif // DROPBEAR_ECDSA
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