END_TEST
/*******************************************************************************
* bitstring
*/
START_TEST(test_asn1_bitstring)
{
chunk_t a = chunk_empty;
chunk_t b = chunk_from_chars(0x03, 0x05, 0x00, 0xa1, 0xa2, 0xa3, 0xa4);
chunk_t c = chunk_from_chars(0xa1, 0xa2, 0xa3, 0xa4);
chunk_t d = chunk_clone(c);
a = asn1_bitstring("c", c);
ck_assert(chunk_equals(a, b));
chunk_free(&a);
a = asn1_bitstring("m", d);
ck_assert(chunk_equals(a, b));
chunk_free(&a);
}
/**
* Generate a transaction id as the MD5 hash of an public key
* the transaction id is also used as a unique serial number
*/
void scep_generate_transaction_id(public_key_t *key, chunk_t *transID,
chunk_t *serialNumber)
{
chunk_t digest = chunk_alloca(HASH_SIZE_MD5);
chunk_t keyEncoding = chunk_empty, keyInfo;
hasher_t *hasher;
bool msb_set;
u_char *pos;
key->get_encoding(key, PUBKEY_ASN1_DER, &keyEncoding);
keyInfo = asn1_wrap(ASN1_SEQUENCE, "mm",
asn1_algorithmIdentifier(OID_RSA_ENCRYPTION),
asn1_bitstring("m", keyEncoding));
hasher = lib->crypto->create_hasher(lib->crypto, HASH_MD5);
if (!hasher || !hasher->get_hash(hasher, keyInfo, digest.ptr))
{
memset(digest.ptr, 0, digest.len);
}
DESTROY_IF(hasher);
free(keyInfo.ptr);
/* is the most significant bit of the digest set? */
msb_set = (*digest.ptr & 0x80) == 0x80;
/* allocate space for the serialNumber */
serialNumber->len = msb_set + digest.len;
serialNumber->ptr = malloc(serialNumber->len);
/* the serial number as the two's complement of the digest */
pos = serialNumber->ptr;
if (msb_set)
{
*pos++ = 0x00;
}
memcpy(pos, digest.ptr, digest.len);
/* the transaction id is the serial number in hex format */
*transID = chunk_to_hex(digest, NULL, TRUE);
}
/**
* Load a generic public key from an SSH key blob
*/
static sshkey_public_key_t *parse_public_key(chunk_t blob)
{
bio_reader_t *reader;
chunk_t format;
reader = bio_reader_create(blob);
if (!reader->read_data32(reader, &format))
{
DBG1(DBG_LIB, "invalid key format in SSH key");
reader->destroy(reader);
return NULL;
}
if (chunk_equals(format, chunk_from_str("ssh-rsa")))
{
chunk_t n, e;
if (!reader->read_data32(reader, &e) ||
!reader->read_data32(reader, &n))
{
DBG1(DBG_LIB, "invalid RSA key in SSH key");
reader->destroy(reader);
return NULL;
}
reader->destroy(reader);
return lib->creds->create(lib->creds, CRED_PUBLIC_KEY, KEY_RSA,
BUILD_RSA_MODULUS, n, BUILD_RSA_PUB_EXP, e, BUILD_END);
}
else if (format.len > strlen(ECDSA_PREFIX) &&
strneq(format.ptr, ECDSA_PREFIX, strlen(ECDSA_PREFIX)))
{
chunk_t ec_blob, identifier, q, oid, encoded;
sshkey_public_key_t *key;
ec_blob = reader->peek(reader);
reader->destroy(reader);
reader = bio_reader_create(ec_blob);
if (!reader->read_data32(reader, &identifier) ||
!reader->read_data32(reader, &q))
{
DBG1(DBG_LIB, "invalid ECDSA key in SSH key");
reader->destroy(reader);
return NULL;
}
oid = parse_ec_identifier(identifier);
if (!oid.ptr)
{
DBG1(DBG_LIB, "invalid ECDSA key identifier in SSH key");
reader->destroy(reader);
return NULL;
}
reader->destroy(reader);
/* build key from subjectPublicKeyInfo */
encoded = asn1_wrap(ASN1_SEQUENCE, "mm",
asn1_wrap(ASN1_SEQUENCE, "mm",
asn1_build_known_oid(OID_EC_PUBLICKEY), oid),
asn1_bitstring("c", q));
key = lib->creds->create(lib->creds, CRED_PUBLIC_KEY,
KEY_ECDSA, BUILD_BLOB_ASN1_DER, encoded, BUILD_END);
chunk_free(&encoded);
return key;
}
DBG1(DBG_LIB, "unsupported SSH key format %.*s", (int)format.len,
format.ptr);
reader->destroy(reader);
return NULL;
}
