monitor_wrap.c

OpenSSL Source code for SFTP, SSH, and many others

	buffer_put_int(&b, enc->block_size);
	buffer_put_string(&b, enc->key, enc->key_len);
	packet_get_keyiv(mode, enc->iv, enc->block_size);
	buffer_put_string(&b, enc->iv, enc->block_size);

	/* Mac structure */
	buffer_put_cstring(&b, mac->name);
	buffer_put_int(&b, mac->enabled);
	buffer_put_string(&b, mac->key, mac->key_len);

	/* Comp structure */
	buffer_put_int(&b, comp->type);
	buffer_put_int(&b, comp->enabled);
	buffer_put_cstring(&b, comp->name);

	len = buffer_len(&b);
	buf = xmalloc(len);
	memcpy(buf, buffer_ptr(&b), len);
	memset(buffer_ptr(&b), 0, len);
	buffer_free(&b);
	if (lenp != NULL)
		*lenp = len;
	if (blobp != NULL)
		*blobp = buf;
	return len;
}

static void
mm_send_kex(Buffer *m, Kex *kex)
{
	buffer_put_string(m, kex->session_id, kex->session_id_len);
	buffer_put_int(m, kex->we_need);
	buffer_put_int(m, kex->hostkey_type);
	buffer_put_int(m, kex->kex_type);
	buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
	buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
	buffer_put_int(m, kex->flags);
	buffer_put_cstring(m, kex->client_version_string);
	buffer_put_cstring(m, kex->server_version_string);
}

void
mm_send_keystate(struct monitor *pmonitor)
{
	Buffer m;
	u_char *blob, *p;
	u_int bloblen, plen;

	buffer_init(&m);

	if (!compat20) {
		u_char iv[24];
		u_char *key;
		u_int ivlen, keylen;

		buffer_put_int(&m, packet_get_protocol_flags());

		buffer_put_int(&m, packet_get_ssh1_cipher());

		debug3("%s: Sending ssh1 KEY+IV", __func__);
		keylen = packet_get_encryption_key(NULL);
		key = xmalloc(keylen+1);	/* add 1 if keylen == 0 */
		keylen = packet_get_encryption_key(key);
		buffer_put_string(&m, key, keylen);
		memset(key, 0, keylen);
		xfree(key);

		ivlen = packet_get_keyiv_len(MODE_OUT);
		packet_get_keyiv(MODE_OUT, iv, ivlen);
		buffer_put_string(&m, iv, ivlen);
		ivlen = packet_get_keyiv_len(MODE_OUT);
		packet_get_keyiv(MODE_IN, iv, ivlen);
		buffer_put_string(&m, iv, ivlen);
		goto skip;
	} else {
		/* Kex for rekeying */
		mm_send_kex(&m, *pmonitor->m_pkex);
	}

	debug3("%s: Sending new keys: %p %p",
	    __func__, newkeys[MODE_OUT], newkeys[MODE_IN]);

	/* Keys from Kex */
	if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
		fatal("%s: conversion of newkeys failed", __func__);

	buffer_put_string(&m, blob, bloblen);
	xfree(blob);

	if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
		fatal("%s: conversion of newkeys failed", __func__);

	buffer_put_string(&m, blob, bloblen);
	xfree(blob);

	buffer_put_int(&m, packet_get_seqnr(MODE_OUT));
	buffer_put_int(&m, packet_get_seqnr(MODE_IN));

	debug3("%s: New keys have been sent", __func__);
 skip:
	/* More key context */
	plen = packet_get_keycontext(MODE_OUT, NULL);
	p = xmalloc(plen+1);
	packet_get_keycontext(MODE_OUT, p);
	buffer_put_string(&m, p, plen);
	xfree(p);

	plen = packet_get_keycontext(MODE_IN, NULL);
	p = xmalloc(plen+1);
	packet_get_keycontext(MODE_IN, p);
	buffer_put_string(&m, p, plen);
	xfree(p);

	/* Compression state */
	debug3("%s: Sending compression state", __func__);
	buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
	buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));

	/* Network I/O buffers */
	buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input));
	buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output));

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
	debug3("%s: Finished sending state", __func__);

	buffer_free(&m);
}

int
mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen)
{
	Buffer m;
	u_char *p;
	int success = 0;

	buffer_init(&m);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);

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

	success = buffer_get_int(&m);
	if (success == 0) {
		debug3("%s: pty alloc failed", __func__);
		buffer_free(&m);
		return (0);
	}
	p = buffer_get_string(&m, NULL);
	buffer_free(&m);

	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
	xfree(p);

	*ptyfd = mm_receive_fd(pmonitor->m_recvfd);
	*ttyfd = mm_receive_fd(pmonitor->m_recvfd);

	/* Success */
	return (1);
}

void
mm_session_pty_cleanup2(void *session)
{
	Session *s = session;
	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 (close(s->ptymaster) < 0)
		error("close(s->ptymaster): %s", strerror(errno));

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

#ifdef USE_PAM
void
mm_start_pam(char *user)
{
	Buffer m;

	debug3("%s entering", __func__);

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

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

	buffer_free(&m);
}
#endif /* USE_PAM */

/* Request process termination */

void
mm_terminate(void)
{
	Buffer m;

	buffer_init(&m);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
	buffer_free(&m);
}

int
mm_ssh1_session_key(BIGNUM *num)
{
	int rsafail;
	Buffer m;

	buffer_init(&m);
	buffer_put_bignum2(&m, num);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);

	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);

	rsafail = buffer_get_int(&m);
	buffer_get_bignum2(&m, num);

	buffer_free(&m);

	return (rsafail);
}

static void
mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
    char ***prompts, u_int **echo_on)
{
	*name = xstrdup("");
	*infotxt = xstrdup("");
	*numprompts = 1;
	*prompts = xmalloc(*numprompts * sizeof(char*));
	*echo_on = xmalloc(*numprompts * sizeof(u_int));
	(*echo_on)[0] = 0;
}

int
mm_bsdauth_query(void *ctx, char **name, char **infotxt,
   u_int *numprompts, char ***prompts, u_int **echo_on)
{
	Buffer m;
	int res;
	char *challenge;

	debug3("%s: entering", __func__);

	buffer_init(&m);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);

	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
	    &m);
	res = buffer_get_int(&m);
	if (res == -1) {
		debug3("%s: no challenge", __func__);
		buffer_free(&m);
		return (-1);
	}

	/* Get the challenge, and format the response */
	challenge  = buffer_get_string(&m, NULL);
	buffer_free(&m);

	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
	(*prompts)[0] = challenge;

	debug3("%s: received challenge: %s", __func__, challenge);

	return (0);
}

int
mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
{
	Buffer m;
	int authok;

	debug3("%s: entering", __func__);
	if (numresponses != 1)
		return (-1);

	buffer_init(&m);
	buffer_put_cstring(&m, responses[0]);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);

	mm_request_receive_expect(pmonitor->m_recvfd,
	    MONITOR_ANS_BSDAUTHRESPOND, &m);

	authok = buffer_get_int(&m);
	buffer_free(&m);

	return ((authok == 0) ? -1 : 0);
}

int
mm_skey_query(void *ctx, char **name, char **infotxt,
   u_int *numprompts, char ***prompts, u_int **echo_on)
{
	Buffer m;
	int len, res;
	char *p, *challenge;

	debug3("%s: entering", __func__);

	buffer_init(&m);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);

	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
	    &m);
	res = buffer_get_int(&m);
	if (res == -1) {
		debug3("%s: no challenge", __func__);
		buffer_free(&m);
		return (-1);
	}

	/* Get the challenge, and format the response */
	challenge  = buffer_get_string(&m, NULL);
	buffer_free(&m);

	debug3("%s: received challenge: %s", __func__, challenge);

	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);

	len = strlen(challenge) + strlen(SKEY_PROMPT) + 1;
	p = xmalloc(len);
	strlcpy(p, challenge, len);
	strlcat(p, SKEY_PROMPT, len);
	(*prompts)[0] = p;
	xfree(challenge);

	return (0);
}

int
mm_skey_respond(void *ctx, u_int numresponses, char **responses)
{
	Buffer m;
	int authok;

	debug3("%s: entering", __func__);
	if (numresponses != 1)
		return (-1);

	buffer_init(&m);
	buffer_put_cstring(&m, responses[0]);
	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);

	mm_request_receive_expect(pmonitor->m_recvfd,
	    MONITOR_ANS_SKEYRESPOND, &m);

	authok = buffer_get_int(&m);
	buffer_free(&m);

	return ((authok == 0) ? -1 : 0);
}

void
mm_ssh1_session_id(u_char session_id[16])
{
	Buffer m;
	int i;

	debug3("%s entering", __func__);

	buffer_init(&m);
	for (i = 0; i < 16; i++)
		buffer_put_char(&m, session_id[i]);

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
	buffer_free(&m);
}

int
mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
{
	Buffer m;
	Key *key;
	u_char *blob;
	u_int blen;
	int allowed = 0;

	debug3("%s entering", __func__);

	buffer_init(&m);
	buffer_put_bignum2(&m, client_n);

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);

	allowed = buffer_get_int(&m);

	if (allowed && rkey != NULL) {
		blob = buffer_get_string(&m, &blen);
		if ((key = key_from_blob(blob, blen)) == NULL)
			fatal("%s: key_from_blob failed", __func__);
		*rkey = key;
		xfree(blob);
	}
	mm_send_debug(&m);
	buffer_free(&m);

	return (allowed);
}

BIGNUM *
mm_auth_rsa_generate_challenge(Key *key)
{
	Buffer m;
	BIGNUM *challenge;
	u_char *blob;
	u_int blen;

	debug3("%s entering", __func__);

	if ((challenge = BN_new()) == NULL)
		fatal("%s: BN_new failed", __func__);

	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
	if (key_to_blob(key, &blob, &blen) == 0)
		fatal("%s: key_to_blob failed", __func__);
	key->type = KEY_RSA1;

	buffer_init(&m);
	buffer_put_string(&m, blob, blen);
	xfree(blob);

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);

	buffer_get_bignum2(&m, challenge);
	buffer_free(&m);

	return (challenge);
}

int
mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
{
	Buffer m;
	u_char *blob;
	u_int blen;
	int success = 0;

	debug3("%s entering", __func__);

	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
	if (key_to_blob(key, &blob, &blen) == 0)
		fatal("%s: key_to_blob failed", __func__);
	key->type = KEY_RSA1;

	buffer_init(&m);
	buffer_put_string(&m, blob, blen);
	buffer_put_string(&m, response, 16);
	xfree(blob);

	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);

	success = buffer_get_int(&m);
	buffer_free(&m);

	return (success);
}