blob: 88ff68330ae9097a2255644eff1e324f0b70d510 [file] [log] [blame]
/* $OpenBSD: monitor_wrap.c,v 1.76 2013/05/17 00:13:13 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>
#include <openssl/bn.h>
#include <openssl/dh.h>
#include <openssl/evp.h>
#include "openbsd-compat/sys-queue.h"
#include "xmalloc.h"
#include "ssh.h"
#include "dh.h"
#include "buffer.h"
#include "key.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"
#ifdef TARGET_OS_MAC /* XXX Broken krb5 headers on Mac */
#undef TARGET_OS_MAC
#include "zlib.h"
#define TARGET_OS_MAC 1
#else
#include "zlib.h"
#endif
#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 "schnorr.h"
#include "jpake.h"
#include "uuencode.h"
#include "channels.h"
#include "session.h"
#include "servconf.h"
#include "roaming.h"
/* Imports */
extern int compat20;
extern z_stream incoming_stream;
extern z_stream outgoing_stream;
extern struct monitor *pmonitor;
extern Buffer loginmsg;
extern ServerOptions options;
void
mm_log_handler(LogLevel level, const char *msg, void *ctx)
{
Buffer log_msg;
struct monitor *mon = (struct monitor *)ctx;
if (mon->m_log_sendfd == -1)
fatal("%s: no log channel", __func__);
buffer_init(&log_msg);
/*
* Placeholder for packet length. Will be filled in with the actual
* packet length once the packet has been constucted. This saves
* fragile math.
*/
buffer_put_int(&log_msg, 0);
buffer_put_int(&log_msg, level);
buffer_put_cstring(&log_msg, msg);
put_u32(buffer_ptr(&log_msg), buffer_len(&log_msg) - 4);
if (atomicio(vwrite, mon->m_log_sendfd, buffer_ptr(&log_msg),
buffer_len(&log_msg)) != buffer_len(&log_msg))
fatal("%s: write: %s", __func__, strerror(errno));
buffer_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, Buffer *m)
{
u_int mlen = buffer_len(m);
u_char buf[5];
debug3("%s entering: type %d", __func__, type);
put_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, buffer_ptr(m), mlen) != mlen)
fatal("%s: write: %s", __func__, strerror(errno));
}
void
mm_request_receive(int sock, Buffer *m)
{
u_char buf[4];
u_int msg_len;
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 = get_u32(buf);
if (msg_len > 256 * 1024)
fatal("%s: read: bad msg_len %d", __func__, msg_len);
buffer_clear(m);
buffer_append_space(m, msg_len);
if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
fatal("%s: read: %s", __func__, strerror(errno));
}
void
mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
{
u_char rtype;
debug3("%s entering: type %d", __func__, type);
mm_request_receive(sock, m);
rtype = buffer_get_char(m);
if (rtype != type)
fatal("%s: read: rtype %d != type %d", __func__,
rtype, type);
}
DH *
mm_choose_dh(int min, int nbits, int max)
{
BIGNUM *p, *g;
int success = 0;
Buffer m;
buffer_init(&m);
buffer_put_int(&m, min);
buffer_put_int(&m, nbits);
buffer_put_int(&m, max);
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);
success = buffer_get_char(&m);
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__);
buffer_get_bignum2(&m, p);
buffer_get_bignum2(&m, g);
debug3("%s: remaining %d", __func__, buffer_len(&m));
buffer_free(&m);
return (dh_new_group(g, p));
}
int
mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
{
Kex *kex = *pmonitor->m_pkex;
Buffer m;
debug3("%s entering", __func__);
buffer_init(&m);
buffer_put_int(&m, kex->host_key_index(key));
buffer_put_string(&m, data, datalen);
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);
*sigp = buffer_get_string(&m, lenp);
buffer_free(&m);
return (0);
}
struct passwd *
mm_getpwnamallow(const char *username)
{
Buffer m;
struct passwd *pw;
u_int len, i;
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);
#ifdef HAVE_STRUCT_PASSWD_PW_GECOS
pw->pw_gecos = buffer_get_string(&m, NULL);
#endif
#ifdef HAVE_STRUCT_PASSWD_PW_CLASS
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__);
#define M_CP_STROPT(x) do { \
if (newopts->x != NULL) \
newopts->x = buffer_get_string(&m, NULL); \
} while (0)
#define M_CP_STRARRAYOPT(x, nx) do { \
for (i = 0; i < newopts->nx; i++) \
newopts->x[i] = buffer_get_string(&m, NULL); \
} 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);
free(newopts);
buffer_free(&m);
return (pw);
}
char *
mm_auth2_read_banner(void)
{
Buffer m;
char *banner;
debug3("%s entering", __func__);
buffer_init(&m);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
buffer_clear(&m);
mm_request_receive_expect(pmonitor->m_recvfd,
MONITOR_ANS_AUTH2_READ_BANNER, &m);
banner = buffer_get_string(&m, NULL);
buffer_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)
{
Buffer m;
debug3("%s entering", __func__);
buffer_init(&m);
buffer_put_cstring(&m, service);
buffer_put_cstring(&m, style ? style : "");
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
buffer_free(&m);
}
/* Do the password authentication */
int
mm_auth_password(Authctxt *authctxt, char *password)
{
Buffer m;
int authenticated = 0;
debug3("%s entering", __func__);
buffer_init(&m);
buffer_put_cstring(&m, password);
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);
authenticated = buffer_get_int(&m);
buffer_free(&m);
debug3("%s: user %sauthenticated",
__func__, authenticated ? "" : "not ");
return (authenticated);
}
int
mm_user_key_allowed(struct passwd *pw, Key *key)
{
return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
}
int
mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
Key *key)
{
return (mm_key_allowed(MM_HOSTKEY, user, host, key));
}
int
mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
char *host, Key *key)
{
int ret;
key->type = KEY_RSA; /* XXX hack for key_to_blob */
ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
key->type = KEY_RSA1;
return (ret);
}
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);
free(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);
}
/*
* 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_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
{
Buffer m;
u_char *blob;
u_int len;
int verified = 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_string(&m, blob, len);
buffer_put_string(&m, sig, siglen);
buffer_put_string(&m, data, datalen);
free(blob);
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);
verified = buffer_get_int(&m);
buffer_free(&m);
return (verified);
}
/* Export key state after authentication */
Newkeys *
mm_newkeys_from_blob(u_char *blob, int blen)
{
Buffer b;
u_int len;
Newkeys *newkey = NULL;
Enc *enc;
Mac *mac;
Comp *comp;
debug3("%s: %p(%d)", __func__, blob, blen);
#ifdef DEBUG_PK
dump_base64(stderr, blob, blen);
#endif
buffer_init(&b);
buffer_append(&b, blob, blen);
newkey = xmalloc(sizeof(*newkey));
enc = &newkey->enc;
mac = &newkey->mac;
comp = &newkey->comp;
/* Enc structure */
enc->name = buffer_get_string(&b, NULL);
buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
enc->enabled = buffer_get_int(&b);
enc->block_size = buffer_get_int(&b);
enc->key = buffer_get_string(&b, &enc->key_len);
enc->iv = buffer_get_string(&b, &enc->iv_len);
if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
fatal("%s: bad cipher name %s or pointer %p", __func__,
enc->name, enc->cipher);
/* Mac structure */
if (cipher_authlen(enc->cipher) == 0) {
mac->name = buffer_get_string(&b, NULL);
if (mac->name == NULL || mac_setup(mac, mac->name) == -1)
fatal("%s: can not setup mac %s", __func__, mac->name);
mac->enabled = buffer_get_int(&b);
mac->key = buffer_get_string(&b, &len);
if (len > mac->key_len)
fatal("%s: bad mac key length: %u > %d", __func__, len,
mac->key_len);
mac->key_len = len;
}
/* Comp structure */
comp->type = buffer_get_int(&b);
comp->enabled = buffer_get_int(&b);
comp->name = buffer_get_string(&b, NULL);
len = buffer_len(&b);
if (len != 0)
error("newkeys_from_blob: remaining bytes in blob %u", len);
buffer_free(&b);
return (newkey);
}
int
mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
{
Buffer b;
int len;
Enc *enc;
Mac *mac;
Comp *comp;
Newkeys *newkey = (Newkeys *)packet_get_newkeys(mode);
debug3("%s: converting %p", __func__, newkey);
if (newkey == NULL) {
error("%s: newkey == NULL", __func__);
return 0;
}
enc = &newkey->enc;
mac = &newkey->mac;
comp = &newkey->comp;
buffer_init(&b);
/* Enc structure */
buffer_put_cstring(&b, enc->name);
/* The cipher struct is constant and shared, you export pointer */
buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
buffer_put_int(&b, enc->enabled);
buffer_put_int(&b, enc->block_size);
buffer_put_string(&b, enc->key, enc->key_len);
packet_get_keyiv(mode, enc->iv, enc->iv_len);
buffer_put_string(&b, enc->iv, enc->iv_len);
/* Mac structure */
if (cipher_authlen(enc->cipher) == 0) {
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);
if (lenp != NULL)
*lenp = len;
if (blobp != NULL) {
*blobp = xmalloc(len);
memcpy(*blobp, buffer_ptr(&b), len);
}
memset(buffer_ptr(&b), 0, len);
buffer_free(&b);
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 *monitor)
{
Buffer m, *input, *output;
u_char *blob, *p;
u_int bloblen, plen;
u_int32_t seqnr, packets;
u_int64_t blocks, bytes;
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);
free(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_IN);
packet_get_keyiv(MODE_IN, iv, ivlen);
buffer_put_string(&m, iv, ivlen);
goto skip;
} else {
/* Kex for rekeying */
mm_send_kex(&m, *monitor->m_pkex);
}
debug3("%s: Sending new keys: %p %p",
__func__, packet_get_newkeys(MODE_OUT),
packet_get_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);
free(blob);
if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
fatal("%s: conversion of newkeys failed", __func__);
buffer_put_string(&m, blob, bloblen);
free(blob);
packet_get_state(MODE_OUT, &seqnr, &blocks, &packets, &bytes);
buffer_put_int(&m, seqnr);
buffer_put_int64(&m, blocks);
buffer_put_int(&m, packets);
buffer_put_int64(&m, bytes);
packet_get_state(MODE_IN, &seqnr, &blocks, &packets, &bytes);
buffer_put_int(&m, seqnr);
buffer_put_int64(&m, blocks);
buffer_put_int(&m, packets);
buffer_put_int64(&m, bytes);
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);
free(p);
plen = packet_get_keycontext(MODE_IN, NULL);
p = xmalloc(plen+1);
packet_get_keycontext(MODE_IN, p);
buffer_put_string(&m, p, plen);
free(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 */
input = (Buffer *)packet_get_input();
output = (Buffer *)packet_get_output();
buffer_put_string(&m, buffer_ptr(input), buffer_len(input));
buffer_put_string(&m, buffer_ptr(output), buffer_len(output));
/* Roaming */
if (compat20) {
buffer_put_int64(&m, get_sent_bytes());
buffer_put_int64(&m, get_recv_bytes());
}
mm_request_send(monitor->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, size_t namebuflen)
{
Buffer m;
char *p, *msg;
int success = 0, tmp1 = -1, tmp2 = -1;
/* 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);
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);
msg = buffer_get_string(&m, NULL);
buffer_free(&m);
strlcpy(namebuf, p, namebuflen); /* Possible truncation */
free(p);
buffer_append(&loginmsg, msg, strlen(msg));
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)
{
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;
}
#ifdef USE_PAM
void
mm_start_pam(Authctxt *authctxt)
{
Buffer m;
debug3("%s entering", __func__);
if (!options.use_pam)
fatal("UsePAM=no, but ended up in %s anyway", __func__);
buffer_init(&m);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
buffer_free(&m);
}
u_int
mm_do_pam_account(void)
{
Buffer m;
u_int ret;
char *msg;
debug3("%s entering", __func__);
if (!options.use_pam)
fatal("UsePAM=no, but ended up in %s anyway", __func__);
buffer_init(&m);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
mm_request_receive_expect(pmonitor->m_recvfd,
MONITOR_ANS_PAM_ACCOUNT, &m);
ret = buffer_get_int(&m);
msg = buffer_get_string(&m, NULL);
buffer_append(&loginmsg, msg, strlen(msg));
free(msg);
buffer_free(&m);
debug3("%s returning %d", __func__, ret);
return (ret);
}
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
mm_sshpam_query(void *ctx, char **name, char **info,
u_int *num, char ***prompts, u_int **echo_on)
{
Buffer m;
u_int i;
int ret;
debug3("%s", __func__);
buffer_init(&m);
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);
ret = buffer_get_int(&m);
debug3("%s: pam_query returned %d", __func__, ret);
*name = buffer_get_string(&m, NULL);
*info = buffer_get_string(&m, NULL);
*num = buffer_get_int(&m);
if (*num > PAM_MAX_NUM_MSG)
fatal("%s: recieved %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) {
(*prompts)[i] = buffer_get_string(&m, NULL);
(*echo_on)[i] = buffer_get_int(&m);
}
buffer_free(&m);
return (ret);
}
int
mm_sshpam_respond(void *ctx, u_int num, char **resp)
{
Buffer m;
u_int i;
int 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_sshpam_free_ctx(void *ctxtp)
{
Buffer m;
debug3("%s", __func__);
buffer_init(&m);
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);
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 = 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)
{
Buffer m;
u_int success;
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);
success = buffer_get_int(&m);
if (success == 0) {
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);
}
#ifdef SKEY
int
mm_skey_query(void *ctx, char **name, char **infotxt,
u_int *numprompts, char ***prompts, u_int **echo_on)
{
Buffer m;
u_int success;
char *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);
success = buffer_get_int(&m);
if (success == 0) {
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);
xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT);
free(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);
}
#endif /* SKEY */
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, have_forced = 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);
/* fake forced command */
auth_clear_options();
have_forced = buffer_get_int(&m);
forced_command = have_forced ? xstrdup("true") : NULL;
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;
free(blob);
}
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);
free(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);
free(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);
}
#ifdef SSH_AUDIT_EVENTS
void
mm_audit_event(ssh_audit_event_t event)
{
Buffer m;
debug3("%s entering", __func__);
buffer_init(&m);
buffer_put_int(&m, event);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
buffer_free(&m);
}
void
mm_audit_run_command(const char *command)
{
Buffer m;
debug3("%s entering command %s", __func__, command);
buffer_init(&m);
buffer_put_cstring(&m, command);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
buffer_free(&m);
}
#endif /* SSH_AUDIT_EVENTS */
#ifdef GSSAPI
OM_uint32
mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
{
Buffer m;
OM_uint32 major;
/* Client doesn't get to see the context */
*ctx = NULL;
buffer_init(&m);
buffer_put_string(&m, goid->elements, goid->length);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
major = buffer_get_int(&m);
buffer_free(&m);
return (major);
}
OM_uint32
mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
gss_buffer_desc *out, OM_uint32 *flags)
{
Buffer m;
OM_uint32 major;
u_int len;
buffer_init(&m);
buffer_put_string(&m, in->value, in->length);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
major = buffer_get_int(&m);
out->value = buffer_get_string(&m, &len);
out->length = len;
if (flags)
*flags = buffer_get_int(&m);
buffer_free(&m);
return (major);
}
OM_uint32
mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
{
Buffer m;
OM_uint32 major;
buffer_init(&m);
buffer_put_string(&m, gssbuf->value, gssbuf->length);
buffer_put_string(&m, gssmic->value, gssmic->length);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
&m);
major = buffer_get_int(&m);
buffer_free(&m);
return(major);
}
int
mm_ssh_gssapi_userok(char *user)
{
Buffer m;
int authenticated = 0;
buffer_init(&m);
mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
&m);
authenticated = buffer_get_int(&m);
buffer_free(&m);
debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
return (authenticated);
}
#endif /* GSSAPI */
#ifdef JPAKE
void
mm_auth2_jpake_get_pwdata(Authctxt *authctxt, BIGNUM **s,
char **hash_scheme, char **salt)
{
Buffer m;
debug3("%s entering", __func__);
buffer_init(&m);
mm_request_send(pmonitor->m_recvfd,
MONITOR_REQ_JPAKE_GET_PWDATA, &m);
debug3("%s: waiting for MONITOR_ANS_JPAKE_GET_PWDATA", __func__);
mm_request_receive_expect(pmonitor->m_recvfd,
MONITOR_ANS_JPAKE_GET_PWDATA, &m);
*hash_scheme = buffer_get_string(&m, NULL);
*salt = buffer_get_string(&m, NULL);
buffer_free(&m);
}
void
mm_jpake_step1(struct modp_group *grp,
u_char **id, u_int *id_len,
BIGNUM **priv1, BIGNUM **priv2, BIGNUM **g_priv1, BIGNUM **g_priv2,
u_char **priv1_proof, u_int *priv1_proof_len,
u_char **priv2_proof, u_int *priv2_proof_len)
{
Buffer m;
debug3("%s entering", __func__);
buffer_init(&m);
mm_request_send(pmonitor->m_recvfd,
MONITOR_REQ_JPAKE_STEP1, &m);
debug3("%s: waiting for MONITOR_ANS_JPAKE_STEP1", __func__);
mm_request_receive_expect(pmonitor->m_recvfd,
MONITOR_ANS_JPAKE_STEP1, &m);
if ((*priv1 = BN_new()) == NULL ||
(*priv2 = BN_new()) == NULL ||
(*g_priv1 = BN_new()) == NULL ||
(*g_priv2 = BN_new()) == NULL)
fatal("%s: BN_new", __func__);
*id = buffer_get_string(&m, id_len);
/* priv1 and priv2 are, well, private */
buffer_get_bignum2(&m, *g_priv1);
buffer_get_bignum2(&m, *g_priv2);
*priv1_proof = buffer_get_string(&m, priv1_proof_len);
*priv2_proof = buffer_get_string(&m, priv2_proof_len);
buffer_free(&m);
}
void
mm_jpake_step2(struct modp_group *grp, BIGNUM *s,
BIGNUM *mypub1, BIGNUM *theirpub1, BIGNUM *theirpub2, BIGNUM *mypriv2,
const u_char *theirid, u_int theirid_len,
const u_char *myid, u_int myid_len,
const u_char *theirpub1_proof, u_int theirpub1_proof_len,
const u_char *theirpub2_proof, u_int theirpub2_proof_len,
BIGNUM **newpub,
u_char **newpub_exponent_proof, u_int *newpub_exponent_proof_len)
{
Buffer m;
debug3("%s entering", __func__);
buffer_init(&m);
/* monitor already has all bignums except theirpub1, theirpub2 */
buffer_put_bignum2(&m, theirpub1);
buffer_put_bignum2(&m, theirpub2);
/* monitor already knows our id */
buffer_put_string(&m, theirid, theirid_len);
buffer_put_string(&m, theirpub1_proof, theirpub1_proof_len);
buffer_put_string(&m, theirpub2_proof, theirpub2_proof_len);
mm_request_send(pmonitor->m_recvfd,
MONITOR_REQ_JPAKE_STEP2, &m);
debug3("%s: waiting for MONITOR_ANS_JPAKE_STEP2", __func__);
mm_request_receive_expect(pmonitor->m_recvfd,
MONITOR_ANS_JPAKE_STEP2, &m);
if ((*newpub = BN_new()) == NULL)
fatal("%s: BN_new", __func__);
buffer_get_bignum2(&m, *newpub);
*newpub_exponent_proof = buffer_get_string(&m,
newpub_exponent_proof_len);
buffer_free(&m);
}
void
mm_jpake_key_confirm(struct modp_group *grp, BIGNUM *s, BIGNUM *step2_val,
BIGNUM *mypriv2, BIGNUM *mypub1, BIGNUM *mypub2,
BIGNUM *theirpub1, BIGNUM *theirpub2,
const u_char *my_id, u_int my_id_len,
const u_char *their_id, u_int their_id_len,
const u_char *sess_id, u_int sess_id_len,
const u_char *theirpriv2_s_proof, u_int theirpriv2_s_proof_len,
BIGNUM **k,
u_char **confirm_hash, u_int *confirm_hash_len)
{
Buffer m;
debug3("%s entering", __func__);
buffer_init(&m);
/* monitor already has all bignums except step2_val */
buffer_put_bignum2(&m, step2_val);
/* monitor already knows all the ids */
buffer_put_string(&m, theirpriv2_s_proof, theirpriv2_s_proof_len);
mm_request_send(pmonitor->m_recvfd,
MONITOR_REQ_JPAKE_KEY_CONFIRM, &m);
debug3("%s: waiting for MONITOR_ANS_JPAKE_KEY_CONFIRM", __func__);
mm_request_receive_expect(pmonitor->m_recvfd,
MONITOR_ANS_JPAKE_KEY_CONFIRM, &m);
/* 'k' is sensitive and stays in the monitor */
*confirm_hash = buffer_get_string(&m, confirm_hash_len);
buffer_free(&m);
}
int
mm_jpake_check_confirm(const BIGNUM *k,
const u_char *peer_id, u_int peer_id_len,
const u_char *sess_id, u_int sess_id_len,
const u_char *peer_confirm_hash, u_int peer_confirm_hash_len)
{
Buffer m;
int success = 0;
debug3("%s entering", __func__);
buffer_init(&m);
/* k is dummy in slave, ignored */
/* monitor knows all the ids */
buffer_put_string(&m, peer_confirm_hash, peer_confirm_hash_len);
mm_request_send(pmonitor->m_recvfd,
MONITOR_REQ_JPAKE_CHECK_CONFIRM, &m);
debug3("%s: waiting for MONITOR_ANS_JPAKE_CHECK_CONFIRM", __func__);
mm_request_receive_expect(pmonitor->m_recvfd,
MONITOR_ANS_JPAKE_CHECK_CONFIRM, &m);
success = buffer_get_int(&m);
buffer_free(&m);
debug3("%s: success = %d", __func__, success);
return success;
}
#endif /* JPAKE */