int mm_answer_auth2_read_banner(int socket, Buffer *m)
{
	char *banner;

	buffer_clear(m);
	banner = auth2_read_banner();
	buffer_put_cstring(m, banner != NULL ? banner : "");
	mm_request_send(socket, MONITOR_ANS_AUTH2_READ_BANNER, m);

	if (banner != NULL)
		xfree(banner);

	return (0);
}

void
mm_inform_authrole(char *role)
{
    Buffer m;

    debug3("%s entering", __func__);

    buffer_init(&m);
    buffer_put_cstring(&m, role ? role : "");

    mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHROLE, &m);

    buffer_free(&m);
}

int
mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
{
	Buffer m;
	u_char *blob;
	u_int len;
	int allowed = 0, have_forced = 0;

	debug3("%s entering", __func__);

	/* Convert the key to a blob and the pass it over */
	if (!key_to_blob(key, &blob, &len))
		return (0);

	buffer_init(&m);
	buffer_put_int(&m, type);
	buffer_put_cstring(&m, user ? user : "");
	buffer_put_cstring(&m, host ? host : "");
	buffer_put_string(&m, blob, len);
	xfree(blob);

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);

	debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);

	allowed = buffer_get_int(&m);

	/* fake forced command */
	auth_clear_options();
	have_forced = buffer_get_int(&m);
	forced_command = have_forced ? xstrdup("true") : NULL;

	buffer_free(&m);

	return (allowed);
}

int ssh_rename(const char *oldname, const char *newname)
{
	Buffer msg;
	u_int status, id;
	char *on, *nn;

	buffer_init(&msg);

	on = ftp_path_absolute(oldname);
	nn = ftp_path_absolute(newname);
	stripslash(on);
	stripslash(nn);

	/* Send rename request */
	id = ftp->ssh_id++;
	buffer_put_char(&msg, SSH2_FXP_RENAME);
	buffer_put_int(&msg, id);
	buffer_put_cstring(&msg, on);
	buffer_put_cstring(&msg, nn);
	ssh_cmd( &msg);
	buffer_free(&msg);

	status = ssh_get_status(id);
	if(status != SSH2_FX_OK) {
		ftp_err("Couldn't rename file \"%s\" to \"%s\": %s\n",
				on, nn, fx2txt(status));
		free(on);
		free(nn);
		return -1;
	}

	ftp_cache_flush_mark_for(on);
	ftp_cache_flush_mark_for(nn);
	free(on);
	free(nn);
	return 0;
}

int
ssh_ecdsa_sign(const Key *key, u_char **sigp, u_int *lenp,
    const u_char *data, u_int datalen)
{
	ECDSA_SIG *sig;
	const EVP_MD *evp_md;
	EVP_MD_CTX md;
	u_char digest[EVP_MAX_MD_SIZE];
	u_int len, dlen;
	Buffer b, bb;

	if (key == NULL || key->ecdsa == NULL ||
	    (key->type != KEY_ECDSA && key->type != KEY_ECDSA_CERT)) {
		error("%s: no ECDSA key", __func__);
		return -1;
	}
	evp_md = key_ec_nid_to_evpmd(key->ecdsa_nid);
	EVP_DigestInit(&md, evp_md);
	EVP_DigestUpdate(&md, data, datalen);
	EVP_DigestFinal(&md, digest, &dlen);

	sig = ECDSA_do_sign(digest, dlen, key->ecdsa);
	memset(digest, 'd', sizeof(digest));

	if (sig == NULL) {
		error("%s: sign failed", __func__);
		return -1;
	}

	buffer_init(&bb);
	buffer_put_bignum2(&bb, sig->r);
	buffer_put_bignum2(&bb, sig->s);
	ECDSA_SIG_free(sig);

	buffer_init(&b);
	buffer_put_cstring(&b, key_ssh_name_plain(key));
	buffer_put_string(&b, buffer_ptr(&bb), buffer_len(&bb));
	buffer_free(&bb);
	len = buffer_len(&b);
	if (lenp != NULL)
		*lenp = len;
	if (sigp != NULL) {
		*sigp = xmalloc(len);
		memcpy(*sigp, buffer_ptr(&b), len);
	}
	buffer_free(&b);

	return 0;
}

int
pkcs11_add_provider(char *name, char *pin, Key ***keysp)
{
	Key *k;
	int i, nkeys;
	u_char *blob;
	u_int blen;
	Buffer msg;

	if (fd < 0 && pkcs11_start_helper() < 0)
		return (-1);

	buffer_init(&msg);
	buffer_put_char(&msg, SSH_AGENTC_ADD_SMARTCARD_KEY);
	buffer_put_cstring(&msg, name);
	buffer_put_cstring(&msg, pin);
	send_msg(&msg);
	buffer_clear(&msg);

	if (recv_msg(&msg) == SSH2_AGENT_IDENTITIES_ANSWER) {
		nkeys = buffer_get_int(&msg);
		*keysp = xcalloc(nkeys, sizeof(Key *));
		for (i = 0; i < nkeys; i++) {
			blob = buffer_get_string(&msg, &blen);
			free(buffer_get_string(&msg, NULL));
			k = key_from_blob(blob, blen);
			wrap_key(k->rsa);
			(*keysp)[i] = k;
			free(blob);
		}
	} else {
		nkeys = -1;
	}
	buffer_free(&msg);
	return (nkeys);
}

int
ssh_update_card(AuthenticationConnection *auth, int add, 
    const char *reader_id, const char *pin, u_int life, u_int confirm)
{
	Buffer msg;
	int type, constrained = (life || confirm);

	if (add) {
		type = constrained ?
		    SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED :
		    SSH_AGENTC_ADD_SMARTCARD_KEY;
	} else
		type = SSH_AGENTC_REMOVE_SMARTCARD_KEY;

	buffer_init(&msg);
	buffer_put_char(&msg, type);
	buffer_put_cstring(&msg, reader_id);
	buffer_put_cstring(&msg, pin);
	
	if (constrained) {
		if (life != 0) {
			buffer_put_char(&msg, SSH_AGENT_CONSTRAIN_LIFETIME);
			buffer_put_int(&msg, life);
		}
		if (confirm != 0)
			buffer_put_char(&msg, SSH_AGENT_CONSTRAIN_CONFIRM);
	}

	if (ssh_request_reply(auth, &msg, &msg) == 0) {
		buffer_free(&msg);
		return 0;
	}
	type = buffer_get_char(&msg);
	buffer_free(&msg);
	return decode_reply(type);
}

struct passwd *
mm_getpwnamallow(const char *username)
{
	Buffer m;
	struct passwd *pw;
	u_int len;
	ServerOptions *newopts;

	debug3("%s entering", __func__);

	buffer_init(&m);
	buffer_put_cstring(&m, username);

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);

	debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);

	if (buffer_get_char(&m) == 0) {
		pw = NULL;
		goto out;
	}
	pw = buffer_get_string(&m, &len);
	if (len != sizeof(struct passwd))
		fatal("%s: struct passwd size mismatch", __func__);
	pw->pw_name = buffer_get_string(&m, NULL);
	pw->pw_passwd = buffer_get_string(&m, NULL);
	pw->pw_gecos = buffer_get_string(&m, NULL);
#ifdef HAVE_PW_CLASS_IN_PASSWD
	pw->pw_class = buffer_get_string(&m, NULL);
#endif
	pw->pw_dir = buffer_get_string(&m, NULL);
	pw->pw_shell = buffer_get_string(&m, NULL);

out:
	/* copy options block as a Match directive may have changed some */
	newopts = buffer_get_string(&m, &len);
	if (len != sizeof(*newopts))
		fatal("%s: option block size mismatch", __func__);
	if (newopts->banner != NULL)
		newopts->banner = buffer_get_string(&m, NULL);
	copy_set_server_options(&options, newopts, 1);
	xfree(newopts);

	buffer_free(&m);

	return (pw);
}

void
mm_start_pam(char *user)
{
	Buffer m;

	debug3("%s entering", __func__);
	if (!options.use_pam)
		fatal("UsePAM=no, but ended up in %s anyway", __func__);

	buffer_init(&m);
	buffer_put_cstring(&m, user);

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);

	buffer_free(&m);
}

int
ssh_ed25519_sign(const Key *key, u_char **sigp, u_int *lenp,
    const u_char *data, u_int datalen)
{
	u_char *sig;
	u_int slen, len;
	unsigned long long smlen;
	int ret;
	Buffer b;

	if (key == NULL || key_type_plain(key->type) != KEY_ED25519 ||
	    key->ed25519_sk == NULL) {
		error("%s: no ED25519 key", __func__);
		return -1;
	}

	if (datalen >= UINT_MAX - crypto_sign_ed25519_BYTES) {
		error("%s: datalen %u too long", __func__, datalen);
		return -1;
	}
	smlen = slen = datalen + crypto_sign_ed25519_BYTES;
	sig = xmalloc(slen);

	if ((ret = crypto_sign_ed25519(sig, &smlen, data, datalen,
	    key->ed25519_sk)) != 0 || smlen <= datalen) {
		error("%s: crypto_sign_ed25519 failed: %d", __func__, ret);
		free(sig);
		return -1;
	}
	/* encode signature */
	buffer_init(&b);
	buffer_put_cstring(&b, "ssh-ed25519");
	buffer_put_string(&b, sig, smlen - datalen);
	len = buffer_len(&b);
	if (lenp != NULL)
		*lenp = len;
	if (sigp != NULL) {
		*sigp = xmalloc(len);
		memcpy(*sigp, buffer_ptr(&b), len);
	}
	buffer_free(&b);
	explicit_bzero(sig, slen);
	free(sig);

	return 0;
}

/* put algorithm proposal into buffer */
static void
kex_prop2buf(Buffer *b, char *proposal[PROPOSAL_MAX])
{
	int i;

	buffer_clear(b);
	/*
	 * add a dummy cookie, the cookie will be overwritten by
	 * kex_send_kexinit(), each time a kexinit is set
	 */
	for (i = 0; i < KEX_COOKIE_LEN; i++)
		buffer_put_char(b, 0);
	for (i = 0; i < PROPOSAL_MAX; i++)
		buffer_put_cstring(b, proposal[i]);
	buffer_put_char(b, 0);			/* first_kex_packet_follows */
	buffer_put_int(b, 0);			/* uint32 reserved */
}

/*
 * Derive fake salt as H(username || first_private_host_key)
 * This provides relatively stable fake salts for non-existent
 * users and avoids the jpake method becoming an account validity
 * oracle.
 */
static void
derive_rawsalt(const char *username, u_char *rawsalt, u_int len)
{
	u_char *digest;
	u_int digest_len;
	Buffer b;
	Key *k;

	buffer_init(&b);
	buffer_put_cstring(&b, username);
	if ((k = get_hostkey_by_index(0)) == NULL ||
	    (k->flags & KEY_FLAG_EXT))
		fatal("%s: no hostkeys", __func__);
	switch (k->type) {
	case KEY_RSA1:
	case KEY_RSA:
		if (k->rsa->p == NULL || k->rsa->q == NULL)
			fatal("%s: RSA key missing p and/or q", __func__);
		buffer_put_bignum2(&b, k->rsa->p);
		buffer_put_bignum2(&b, k->rsa->q);
		break;
	case KEY_DSA:
		if (k->dsa->priv_key == NULL)
			fatal("%s: DSA key missing priv_key", __func__);
		buffer_put_bignum2(&b, k->dsa->priv_key);
		break;
	case KEY_ECDSA:
		if (EC_KEY_get0_private_key(k->ecdsa) == NULL)
			fatal("%s: ECDSA key missing priv_key", __func__);
		buffer_put_bignum2(&b, EC_KEY_get0_private_key(k->ecdsa));
		break;
	default:
		fatal("%s: unknown key type %d", __func__, k->type);
	}
	if (hash_buffer(buffer_ptr(&b), buffer_len(&b), EVP_sha256(),
	    &digest, &digest_len) != 0)
		fatal("%s: hash_buffer", __func__);
	buffer_free(&b);
	if (len > digest_len)
		fatal("%s: not enough bytes for rawsalt (want %u have %u)",
		    __func__, len, digest_len);
	memcpy(rawsalt, digest, len);
	bzero(digest, digest_len);
	free(digest);
}

struct shaft_conn *
do_init(int fd_in, int fd_out, struct shaft_flow *flow)
{
	u_int type, version;
	Buffer msg;
	struct shaft_conn *ret;

	buffer_init(&msg);
	buffer_put_char(&msg, SHAFT_INIT);
	buffer_put_int(&msg, SHAFT_VERSION);
	buffer_put_cstring(&msg, flow->local);
	send_msg(fd_out, &msg);

	buffer_clear(&msg);

	get_msg(fd_in, &msg);

	/* Expecting a VERSION reply */
	if ((type = buffer_get_char(&msg)) != SHAFT_VERSION) {
		error("Invalid packet back from SHAFT_INIT (type %u)",
		    version);
		buffer_free(&msg);
		return(NULL);
	}
	version = buffer_get_int(&msg);
	flow->dst = buffer_get_cstring(&msg, NULL);
	if (flow->dst == NULL) {
		error("Invalid packet back from SHAFT_INIT remote addr is null");
		buffer_free(&msg);
		return(NULL);
	}

	debug2("Remote version: %u", version);
	debug2("Remote Address: %s", flow->dst);

	buffer_free(&msg);

	ret = xmalloc(sizeof(*ret));
	ret->fd_in = fd_in;
	ret->fd_out = fd_out;
	ret->version = version;
	ret->msg_id = 1;

	return(ret);
}

/* Lock/unlock agent */
int
ssh_lock_agent(AuthenticationConnection *auth, int lock, const char *password)
{
	int type;
	Buffer msg;

	buffer_init(&msg);
	buffer_put_char(&msg, lock ? SSH_AGENTC_LOCK : SSH_AGENTC_UNLOCK);
	buffer_put_cstring(&msg, password);

	if (ssh_request_reply(auth, &msg, &msg) == 0) {
		buffer_free(&msg);
		return 0;
	}
	type = buffer_get_char(&msg);
	buffer_free(&msg);
	return decode_reply(type);
}

int
mm_answer_skeyquery(int socket, Buffer *m)
{
	struct skey skey;
	char challenge[1024];
	int res;

	res = skeychallenge(&skey, authctxt->user, challenge);

	buffer_clear(m);
	buffer_put_int(m, res);
	if (res != -1)
		buffer_put_cstring(m, challenge);

	debug3("%s: sending challenge res: %d", __func__, res);
	mm_request_send(socket, MONITOR_ANS_SKEYQUERY, m);

	return (0);
}

int
mm_sshpam_respond(void *ctx, u_int num, char **resp)
{
	Buffer m;
	int i, ret;

	debug3("%s", __func__);
	buffer_init(&m);
	buffer_put_int(&m, num);
	for (i = 0; i < num; ++i)
		buffer_put_cstring(&m, resp[i]);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
	debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
	ret = buffer_get_int(&m);
	debug3("%s: pam_respond returned %d", __func__, ret);
	buffer_free(&m);
	return (ret);
}

void
mm_session_pty_cleanup2(Session *s)
{
	Buffer m;

	if (s->ttyfd == -1)
		return;
	buffer_init(&m);
	buffer_put_cstring(&m, s->tty);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
	buffer_free(&m);

	/* closed dup'ed master */
	if (s->ptymaster != -1 && close(s->ptymaster) < 0)
		error("close(s->ptymaster/%d): %s",
		    s->ptymaster, strerror(errno));

	/* unlink pty from session */
	s->ttyfd = -1;
}

static void
send_rexec_state(int fd, Buffer *conf)
{
	Buffer m;

	debug3("%s: entering fd = %d config len %d", __func__, fd,
	    buffer_len(conf));

	/*
	 * Protocol from reexec master to child:
	 *	string	configuration
	 *	u_int	ephemeral_key_follows
	 *	bignum	e		(only if ephemeral_key_follows == 1)
	 *	bignum	n			"
	 *	bignum	d			"
	 *	bignum	iqmp			"
	 *	bignum	p			"
	 *	bignum	q			"
	 */
	buffer_init(&m);
	buffer_put_cstring(&m, buffer_ptr(conf));

	if (sensitive_data.server_key != NULL &&
	    sensitive_data.server_key->type == KEY_RSA1) {
		buffer_put_int(&m, 1);
		buffer_put_bignum(&m, sensitive_data.server_key->rsa->e);
		buffer_put_bignum(&m, sensitive_data.server_key->rsa->n);
		buffer_put_bignum(&m, sensitive_data.server_key->rsa->d);
		buffer_put_bignum(&m, sensitive_data.server_key->rsa->iqmp);
		buffer_put_bignum(&m, sensitive_data.server_key->rsa->p);
		buffer_put_bignum(&m, sensitive_data.server_key->rsa->q);
	} else
		buffer_put_int(&m, 0);

	if (ssh_msg_send(fd, 0, &m) == -1)
		fatal("%s: ssh_msg_send failed", __func__);

	buffer_free(&m);

	debug3("%s: done", __func__);
}

void *
mm_sshpam_init_ctx(Authctxt *authctxt)
{
	Buffer m;
	int success;

	debug3("%s", __func__);
	buffer_init(&m);
	buffer_put_cstring(&m, authctxt->user);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
	debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
	success = buffer_get_int(&m);
	if (success == 0) {
		debug3("%s: pam_init_ctx failed", __func__);
		buffer_free(&m);
		return (NULL);
	}
	buffer_free(&m);
	return (authctxt);
}

int packet_fxp_open(Buffer *buff, Buffer *preped_buff) {
    u_int msg_len;
    u_int xmsg_len;
    
    // File names
    u_int file_len, pflags;
    u_char *filename;
    
    // Copy first part of packet over to prepared buffer
    msg_len = get_u32(buffer_ptr(buff));
    xmsg_len = msg_len;
    
    buffer_append(preped_buff, buffer_ptr(buff), 9);
    buffer_consume(buff, 9);
    xmsg_len -= 5;
    
    // Rewrite path
    filename = buffer_get_string(buff, &file_len);
    filename = unchroot_filename(filename, (u_char*) user_homedir);
    buffer_put_cstring(preped_buff, (char*) filename);
    xmsg_len -= (file_len + 4);
    msg_len += (strlen((char*) filename) - file_len);
    
    // pflags
    pflags = buffer_get_int(buff);
    buffer_put_int(preped_buff, pflags);
    xmsg_len -= 4;
    
    // Copy attributes through, cleaning extensions where required
    parse_attrs(buff, preped_buff, &msg_len, &xmsg_len);
    
    // Copy any remaining packet data over
    buffer_append(preped_buff, buffer_ptr(buff), xmsg_len);
    buffer_consume(buff, xmsg_len);
    
    // Rewrite message length
    put_u32(buffer_end(preped_buff)-msg_len-4, msg_len);
    
    return 1;
}