Adding upstream version 1:7.9p1.upstream/1%7.9p1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1006 insertions, 0 deletions

diff --git a/monitor_wrap.c b/monitor_wrap.c
new file mode 100644
index 0000000..732fb34
--- /dev/null
+++ b/monitor_wrap.c
@@ -0,0 +1,1006 @@
+/* $OpenBSD: monitor_wrap.c,v 1.107 2018/07/20 03:46:34 djm Exp $ */
+/*
+ * Copyright 2002 Niels Provos <provos@citi.umich.edu>
+ * Copyright 2002 Markus Friedl <markus@openbsd.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+#include <sys/uio.h>
+
+#include <errno.h>
+#include <pwd.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifdef WITH_OPENSSL
+#include <openssl/bn.h>
+#include <openssl/dh.h>
+#include <openssl/evp.h>
+#endif
+
+#include "openbsd-compat/sys-queue.h"
+#include "xmalloc.h"
+#include "ssh.h"
+#ifdef WITH_OPENSSL
+#include "dh.h"
+#endif
+#include "sshbuf.h"
+#include "sshkey.h"
+#include "cipher.h"
+#include "kex.h"
+#include "hostfile.h"
+#include "auth.h"
+#include "auth-options.h"
+#include "packet.h"
+#include "mac.h"
+#include "log.h"
+#include "auth-pam.h"
+#include "monitor.h"
+#ifdef GSSAPI
+#include "ssh-gss.h"
+#endif
+#include "monitor_wrap.h"
+#include "atomicio.h"
+#include "monitor_fdpass.h"
+#include "misc.h"
+
+#include "channels.h"
+#include "session.h"
+#include "servconf.h"
+
+#include "ssherr.h"
+
+/* Imports */
+extern struct monitor *pmonitor;
+extern struct sshbuf *loginmsg;
+extern ServerOptions options;
+
+void
+mm_log_handler(LogLevel level, const char *msg, void *ctx)
+{
+	struct sshbuf *log_msg;
+	struct monitor *mon = (struct monitor *)ctx;
+	int r;
+	size_t len;
+
+	if (mon->m_log_sendfd == -1)
+		fatal("%s: no log channel", __func__);
+
+	if ((log_msg = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+
+	if ((r = sshbuf_put_u32(log_msg, 0)) != 0 || /* length; filled below */
+	    (r = sshbuf_put_u32(log_msg, level)) != 0 ||
+	    (r = sshbuf_put_cstring(log_msg, msg)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if ((len = sshbuf_len(log_msg)) < 4 || len > 0xffffffff)
+		fatal("%s: bad length %zu", __func__, len);
+	POKE_U32(sshbuf_mutable_ptr(log_msg), len - 4);
+	if (atomicio(vwrite, mon->m_log_sendfd,
+	    sshbuf_mutable_ptr(log_msg), len) != len)
+		fatal("%s: write: %s", __func__, strerror(errno));
+	sshbuf_free(log_msg);
+}
+
+int
+mm_is_monitor(void)
+{
+	/*
+	 * m_pid is only set in the privileged part, and
+	 * points to the unprivileged child.
+	 */
+	return (pmonitor && pmonitor->m_pid > 0);
+}
+
+void
+mm_request_send(int sock, enum monitor_reqtype type, struct sshbuf *m)
+{
+	size_t mlen = sshbuf_len(m);
+	u_char buf[5];
+
+	debug3("%s entering: type %d", __func__, type);
+
+	if (mlen >= 0xffffffff)
+		fatal("%s: bad length %zu", __func__, mlen);
+	POKE_U32(buf, mlen + 1);
+	buf[4] = (u_char) type;		/* 1st byte of payload is mesg-type */
+	if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
+		fatal("%s: write: %s", __func__, strerror(errno));
+	if (atomicio(vwrite, sock, sshbuf_mutable_ptr(m), mlen) != mlen)
+		fatal("%s: write: %s", __func__, strerror(errno));
+}
+
+void
+mm_request_receive(int sock, struct sshbuf *m)
+{
+	u_char buf[4], *p = NULL;
+	u_int msg_len;
+	int r;
+
+	debug3("%s entering", __func__);
+
+	if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
+		if (errno == EPIPE)
+			cleanup_exit(255);
+		fatal("%s: read: %s", __func__, strerror(errno));
+	}
+	msg_len = PEEK_U32(buf);
+	if (msg_len > 256 * 1024)
+		fatal("%s: read: bad msg_len %d", __func__, msg_len);
+	sshbuf_reset(m);
+	if ((r = sshbuf_reserve(m, msg_len, &p)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (atomicio(read, sock, p, msg_len) != msg_len)
+		fatal("%s: read: %s", __func__, strerror(errno));
+}
+
+void
+mm_request_receive_expect(int sock, enum monitor_reqtype type, struct sshbuf *m)
+{
+	u_char rtype;
+	int r;
+
+	debug3("%s entering: type %d", __func__, type);
+
+	mm_request_receive(sock, m);
+	if ((r = sshbuf_get_u8(m, &rtype)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (rtype != type)
+		fatal("%s: read: rtype %d != type %d", __func__,
+		    rtype, type);
+}
+
+#ifdef WITH_OPENSSL
+DH *
+mm_choose_dh(int min, int nbits, int max)
+{
+	BIGNUM *p, *g;
+	int r;
+	u_char success = 0;
+	struct sshbuf *m;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_u32(m, min)) != 0 ||
+	    (r = sshbuf_put_u32(m, nbits)) != 0 ||
+	    (r = sshbuf_put_u32(m, max)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, m);
+
+	debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
+	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, m);
+
+	if ((r = sshbuf_get_u8(m, &success)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (success == 0)
+		fatal("%s: MONITOR_ANS_MODULI failed", __func__);
+
+	if ((p = BN_new()) == NULL)
+		fatal("%s: BN_new failed", __func__);
+	if ((g = BN_new()) == NULL)
+		fatal("%s: BN_new failed", __func__);
+	if ((r = sshbuf_get_bignum2(m, p)) != 0 ||
+	    (r = sshbuf_get_bignum2(m, g)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	debug3("%s: remaining %zu", __func__, sshbuf_len(m));
+	sshbuf_free(m);
+
+	return (dh_new_group(g, p));
+}
+#endif
+
+int
+mm_sshkey_sign(struct sshkey *key, u_char **sigp, size_t *lenp,
+    const u_char *data, size_t datalen, const char *hostkey_alg, u_int compat)
+{
+	struct kex *kex = *pmonitor->m_pkex;
+	struct sshbuf *m;
+	u_int ndx = kex->host_key_index(key, 0, active_state);
+	int r;
+
+	debug3("%s entering", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_u32(m, ndx)) != 0 ||
+	    (r = sshbuf_put_string(m, data, datalen)) != 0 ||
+	    (r = sshbuf_put_cstring(m, hostkey_alg)) != 0 ||
+	    (r = sshbuf_put_u32(m, compat)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, m);
+
+	debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
+	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, m);
+	if ((r = sshbuf_get_string(m, sigp, lenp)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	sshbuf_free(m);
+
+	return (0);
+}
+
+struct passwd *
+mm_getpwnamallow(const char *username)
+{
+	struct ssh *ssh = active_state;		/* XXX */
+	struct sshbuf *m;
+	struct passwd *pw;
+	size_t len;
+	u_int i;
+	ServerOptions *newopts;
+	int r;
+	u_char ok;
+	const u_char *p;
+
+	debug3("%s entering", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_cstring(m, username)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	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 ((r = sshbuf_get_u8(m, &ok)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (ok == 0) {
+		pw = NULL;
+		goto out;
+	}
+
+	/* XXX don't like passing struct passwd like this */
+	pw = xcalloc(sizeof(*pw), 1);
+	if ((r = sshbuf_get_string_direct(m, &p, &len)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (len != sizeof(*pw))
+		fatal("%s: struct passwd size mismatch", __func__);
+	memcpy(pw, p, sizeof(*pw));
+
+	if ((r = sshbuf_get_cstring(m, &pw->pw_name, NULL)) != 0 ||
+	    (r = sshbuf_get_cstring(m, &pw->pw_passwd, NULL)) != 0 ||
+#ifdef HAVE_STRUCT_PASSWD_PW_GECOS
+	    (r = sshbuf_get_cstring(m, &pw->pw_gecos, NULL)) != 0 ||
+#endif
+#ifdef HAVE_STRUCT_PASSWD_PW_CLASS
+	    (r = sshbuf_get_cstring(m, &pw->pw_class, NULL)) != 0 ||
+#endif
+	    (r = sshbuf_get_cstring(m, &pw->pw_dir, NULL)) != 0 ||
+	    (r = sshbuf_get_cstring(m, &pw->pw_shell, NULL)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+out:
+	/* copy options block as a Match directive may have changed some */
+	if ((r = sshbuf_get_string_direct(m, &p, &len)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (len != sizeof(*newopts))
+		fatal("%s: option block size mismatch", __func__);
+	newopts = xcalloc(sizeof(*newopts), 1);
+	memcpy(newopts, p, sizeof(*newopts));
+
+#define M_CP_STROPT(x) do { \
+		if (newopts->x != NULL) { \
+			if ((r = sshbuf_get_cstring(m, \
+			    &newopts->x, NULL)) != 0) \
+				fatal("%s: buffer error: %s", \
+				    __func__, ssh_err(r)); \
+		} \
+	} while (0)
+#define M_CP_STRARRAYOPT(x, nx) do { \
+		newopts->x = newopts->nx == 0 ? \
+		    NULL : xcalloc(newopts->nx, sizeof(*newopts->x)); \
+		for (i = 0; i < newopts->nx; i++) { \
+			if ((r = sshbuf_get_cstring(m, \
+			    &newopts->x[i], NULL)) != 0) \
+				fatal("%s: buffer error: %s", \
+				    __func__, ssh_err(r)); \
+		} \
+	} while (0)
+	/* See comment in servconf.h */
+	COPY_MATCH_STRING_OPTS();
+#undef M_CP_STROPT
+#undef M_CP_STRARRAYOPT
+
+	copy_set_server_options(&options, newopts, 1);
+	log_change_level(options.log_level);
+	process_permitopen(ssh, &options);
+	free(newopts);
+
+	sshbuf_free(m);
+
+	return (pw);
+}
+
+char *
+mm_auth2_read_banner(void)
+{
+	struct sshbuf *m;
+	char *banner;
+	int r;
+
+	debug3("%s entering", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, m);
+	sshbuf_reset(m);
+
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_AUTH2_READ_BANNER, m);
+	if ((r = sshbuf_get_cstring(m, &banner, NULL)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	sshbuf_free(m);
+
+	/* treat empty banner as missing banner */
+	if (strlen(banner) == 0) {
+		free(banner);
+		banner = NULL;
+	}
+	return (banner);
+}
+
+/* Inform the privileged process about service and style */
+
+void
+mm_inform_authserv(char *service, char *style)
+{
+	struct sshbuf *m;
+	int r;
+
+	debug3("%s entering", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_cstring(m, service)) != 0 ||
+	    (r = sshbuf_put_cstring(m, style ? style : "")) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, m);
+
+	sshbuf_free(m);
+}
+
+/* Do the password authentication */
+int
+mm_auth_password(struct ssh *ssh, char *password)
+{
+	struct sshbuf *m;
+	int r, authenticated = 0;
+#ifdef USE_PAM
+	u_int maxtries = 0;
+#endif
+
+	debug3("%s entering", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_cstring(m, password)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, m);
+
+	debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_AUTHPASSWORD, m);
+
+	if ((r = sshbuf_get_u32(m, &authenticated)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+#ifdef USE_PAM
+	if ((r = sshbuf_get_u32(m, &maxtries)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (maxtries > INT_MAX)
+		fatal("%s: bad maxtries %u", __func__, maxtries);
+	sshpam_set_maxtries_reached(maxtries);
+#endif
+
+	sshbuf_free(m);
+
+	debug3("%s: user %sauthenticated",
+	    __func__, authenticated ? "" : "not ");
+	return (authenticated);
+}
+
+int
+mm_user_key_allowed(struct ssh *ssh, struct passwd *pw, struct sshkey *key,
+    int pubkey_auth_attempt, struct sshauthopt **authoptp)
+{
+	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key,
+	    pubkey_auth_attempt, authoptp));
+}
+
+int
+mm_hostbased_key_allowed(struct passwd *pw, const char *user, const char *host,
+    struct sshkey *key)
+{
+	return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0, NULL));
+}
+
+int
+mm_key_allowed(enum mm_keytype type, const char *user, const char *host,
+    struct sshkey *key, int pubkey_auth_attempt, struct sshauthopt **authoptp)
+{
+	struct sshbuf *m;
+	int r, allowed = 0;
+	struct sshauthopt *opts = NULL;
+
+	debug3("%s entering", __func__);
+
+	if (authoptp != NULL)
+		*authoptp = NULL;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_u32(m, type)) != 0 ||
+	    (r = sshbuf_put_cstring(m, user ? user : "")) != 0 ||
+	    (r = sshbuf_put_cstring(m, host ? host : "")) != 0 ||
+	    (r = sshkey_puts(key, m)) != 0 ||
+	    (r = sshbuf_put_u32(m, pubkey_auth_attempt)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	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);
+
+	if ((r = sshbuf_get_u32(m, &allowed)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (allowed && type == MM_USERKEY) {
+		if ((r = sshauthopt_deserialise(m, &opts)) != 0)
+			fatal("%s: sshauthopt_deserialise: %s",
+			    __func__, ssh_err(r));
+	}
+	sshbuf_free(m);
+
+	if (authoptp != NULL) {
+		*authoptp = opts;
+		opts = NULL;
+	}
+	sshauthopt_free(opts);
+
+	return allowed;
+}
+
+/*
+ * This key verify needs to send the key type along, because the
+ * privileged parent makes the decision if the key is allowed
+ * for authentication.
+ */
+
+int
+mm_sshkey_verify(const struct sshkey *key, const u_char *sig, size_t siglen,
+    const u_char *data, size_t datalen, const char *sigalg, u_int compat)
+{
+	struct sshbuf *m;
+	u_int encoded_ret = 0;
+	int r;
+
+	debug3("%s entering", __func__);
+
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshkey_puts(key, m)) != 0 ||
+	    (r = sshbuf_put_string(m, sig, siglen)) != 0 ||
+	    (r = sshbuf_put_string(m, data, datalen)) != 0 ||
+	    (r = sshbuf_put_cstring(m, sigalg == NULL ? "" : sigalg)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, m);
+
+	debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_KEYVERIFY, m);
+
+	if ((r = sshbuf_get_u32(m, &encoded_ret)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	sshbuf_free(m);
+
+	if (encoded_ret != 0)
+		return SSH_ERR_SIGNATURE_INVALID;
+	return 0;
+}
+
+void
+mm_send_keystate(struct monitor *monitor)
+{
+	struct ssh *ssh = active_state;		/* XXX */
+	struct sshbuf *m;
+	int r;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = ssh_packet_get_state(ssh, m)) != 0)
+		fatal("%s: get_state failed: %s",
+		    __func__, ssh_err(r));
+	mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m);
+	debug3("%s: Finished sending state", __func__);
+	sshbuf_free(m);
+}
+
+int
+mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
+{
+	struct sshbuf *m;
+	char *p, *msg;
+	int success = 0, tmp1 = -1, tmp2 = -1, r;
+
+	/* Kludge: ensure there are fds free to receive the pty/tty */
+	if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 ||
+	    (tmp2 = dup(pmonitor->m_recvfd)) == -1) {
+		error("%s: cannot allocate fds for pty", __func__);
+		if (tmp1 > 0)
+			close(tmp1);
+		if (tmp2 > 0)
+			close(tmp2);
+		return 0;
+	}
+	close(tmp1);
+	close(tmp2);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	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);
+
+	if ((r = sshbuf_get_u32(m, &success)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (success == 0) {
+		debug3("%s: pty alloc failed", __func__);
+		sshbuf_free(m);
+		return (0);
+	}
+	if ((r = sshbuf_get_cstring(m, &p, NULL)) != 0 ||
+	    (r = sshbuf_get_cstring(m, &msg, NULL)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	sshbuf_free(m);
+
+	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
+	free(p);
+
+	if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	free(msg);
+
+	if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 ||
+	    (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1)
+		fatal("%s: receive fds failed", __func__);
+
+	/* Success */
+	return (1);
+}
+
+void
+mm_session_pty_cleanup2(Session *s)
+{
+	struct sshbuf *m;
+	int r;
+
+	if (s->ttyfd == -1)
+		return;
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_cstring(m, s->tty)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, m);
+	sshbuf_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;
+}
+
+#ifdef USE_PAM
+void
+mm_start_pam(Authctxt *authctxt)
+{
+	struct sshbuf *m;
+
+	debug3("%s entering", __func__);
+	if (!options.use_pam)
+		fatal("UsePAM=no, but ended up in %s anyway", __func__);
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, m);
+
+	sshbuf_free(m);
+}
+
+u_int
+mm_do_pam_account(void)
+{
+	struct sshbuf *m;
+	u_int ret;
+	char *msg;
+	size_t msglen;
+	int r;
+
+	debug3("%s entering", __func__);
+	if (!options.use_pam)
+		fatal("UsePAM=no, but ended up in %s anyway", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, m);
+
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_PAM_ACCOUNT, m);
+	if ((r = sshbuf_get_u32(m, &ret)) != 0 ||
+	    (r = sshbuf_get_cstring(m, &msg, &msglen)) != 0 ||
+	    (r = sshbuf_put(loginmsg, msg, msglen)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	free(msg);
+	sshbuf_free(m);
+
+	debug3("%s returning %d", __func__, ret);
+
+	return (ret);
+}
+
+void *
+mm_sshpam_init_ctx(Authctxt *authctxt)
+{
+	struct sshbuf *m;
+	int r, success;
+
+	debug3("%s", __func__);
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	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);
+	if ((r = sshbuf_get_u32(m, &success)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (success == 0) {
+		debug3("%s: pam_init_ctx failed", __func__);
+		sshbuf_free(m);
+		return (NULL);
+	}
+	sshbuf_free(m);
+	return (authctxt);
+}
+
+int
+mm_sshpam_query(void *ctx, char **name, char **info,
+    u_int *num, char ***prompts, u_int **echo_on)
+{
+	struct sshbuf *m;
+	u_int i, n;
+	int r, ret;
+
+	debug3("%s", __func__);
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, m);
+	debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
+	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, m);
+	if ((r = sshbuf_get_u32(m, &ret)) != 0 ||
+	    (r = sshbuf_get_cstring(m, name, NULL)) != 0 ||
+	    (r = sshbuf_get_cstring(m, info, NULL)) != 0 ||
+	    (r = sshbuf_get_u32(m, &n)) != 0 ||
+	    (r = sshbuf_get_u32(m, num)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	debug3("%s: pam_query returned %d", __func__, ret);
+	sshpam_set_maxtries_reached(n);
+	if (*num > PAM_MAX_NUM_MSG)
+		fatal("%s: received %u PAM messages, expected <= %u",
+		    __func__, *num, PAM_MAX_NUM_MSG);
+	*prompts = xcalloc((*num + 1), sizeof(char *));
+	*echo_on = xcalloc((*num + 1), sizeof(u_int));
+	for (i = 0; i < *num; ++i) {
+		if ((r = sshbuf_get_cstring(m, &((*prompts)[i]), NULL)) != 0 ||
+		    (r = sshbuf_get_u32(m, &((*echo_on)[i]))) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	}
+	sshbuf_free(m);
+	return (ret);
+}
+
+int
+mm_sshpam_respond(void *ctx, u_int num, char **resp)
+{
+	struct sshbuf *m;
+	u_int n, i;
+	int r, ret;
+
+	debug3("%s", __func__);
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_u32(m, num)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	for (i = 0; i < num; ++i) {
+		if ((r = sshbuf_put_cstring(m, resp[i])) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	}
+	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);
+	if ((r = sshbuf_get_u32(m, &n)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	ret = (int)n; /* XXX */
+	debug3("%s: pam_respond returned %d", __func__, ret);
+	sshbuf_free(m);
+	return (ret);
+}
+
+void
+mm_sshpam_free_ctx(void *ctxtp)
+{
+	struct sshbuf *m;
+
+	debug3("%s", __func__);
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, m);
+	debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_PAM_FREE_CTX, m);
+	sshbuf_free(m);
+}
+#endif /* USE_PAM */
+
+/* Request process termination */
+
+void
+mm_terminate(void)
+{
+	struct sshbuf *m;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, m);
+	sshbuf_free(m);
+}
+
+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 = xcalloc(*numprompts, sizeof(char *));
+	*echo_on = xcalloc(*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)
+{
+	struct sshbuf *m;
+	u_int success;
+	char *challenge;
+	int r;
+
+	debug3("%s: entering", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, m);
+
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_BSDAUTHQUERY, m);
+	if ((r = sshbuf_get_u32(m, &success)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (success == 0) {
+		debug3("%s: no challenge", __func__);
+		sshbuf_free(m);
+		return (-1);
+	}
+
+	/* Get the challenge, and format the response */
+	if ((r = sshbuf_get_cstring(m, &challenge, NULL)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	sshbuf_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)
+{
+	struct sshbuf *m;
+	int r, authok;
+
+	debug3("%s: entering", __func__);
+	if (numresponses != 1)
+		return (-1);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_cstring(m, responses[0])) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, m);
+
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_BSDAUTHRESPOND, m);
+
+	if ((r = sshbuf_get_u32(m, &authok)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	sshbuf_free(m);
+
+	return ((authok == 0) ? -1 : 0);
+}
+
+#ifdef SSH_AUDIT_EVENTS
+void
+mm_audit_event(ssh_audit_event_t event)
+{
+	struct sshbuf *m;
+	int r;
+
+	debug3("%s entering", __func__);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_u32(m, event)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, m);
+	sshbuf_free(m);
+}
+
+void
+mm_audit_run_command(const char *command)
+{
+	struct sshbuf *m;
+	int r;
+
+	debug3("%s entering command %s", __func__, command);
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_cstring(m, command)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, m);
+	sshbuf_free(m);
+}
+#endif /* SSH_AUDIT_EVENTS */
+
+#ifdef GSSAPI
+OM_uint32
+mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
+{
+	struct sshbuf *m;
+	OM_uint32 major;
+	int r;
+
+	/* Client doesn't get to see the context */
+	*ctx = NULL;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_string(m, goid->elements, goid->length)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, m);
+	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, m);
+
+	if ((r = sshbuf_get_u32(m, &major)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	sshbuf_free(m);
+	return (major);
+}
+
+OM_uint32
+mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
+    gss_buffer_desc *out, OM_uint32 *flagsp)
+{
+	struct sshbuf *m;
+	OM_uint32 major;
+	u_int flags;
+	int r;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_string(m, in->value, in->length)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, m);
+	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, m);
+
+	if ((r = sshbuf_get_u32(m, &major)) != 0 ||
+	    (r = ssh_gssapi_get_buffer_desc(m, out)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if (flagsp != NULL) {
+		if ((r = sshbuf_get_u32(m, &flags)) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+		*flagsp = flags;
+	}
+
+	sshbuf_free(m);
+
+	return (major);
+}
+
+OM_uint32
+mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
+{
+	struct sshbuf *m;
+	OM_uint32 major;
+	int r;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_put_string(m, gssbuf->value, gssbuf->length)) != 0 ||
+	    (r = sshbuf_put_string(m, gssmic->value, gssmic->length)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, m);
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_GSSCHECKMIC, m);
+
+	if ((r = sshbuf_get_u32(m, &major)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	sshbuf_free(m);
+	return(major);
+}
+
+int
+mm_ssh_gssapi_userok(char *user)
+{
+	struct sshbuf *m;
+	int r, authenticated = 0;
+
+	if ((m = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+
+	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, m);
+	mm_request_receive_expect(pmonitor->m_recvfd,
+	    MONITOR_ANS_GSSUSEROK, m);
+
+	if ((r = sshbuf_get_u32(m, &authenticated)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	sshbuf_free(m);
+	debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
+	return (authenticated);
+}
+#endif /* GSSAPI */