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856f0be669
[auth-passwd.c auth.c auth.h auth1.c auth2-none.c auth2-passwd.c] [auth2.c monitor.c] fix passwd auth for 'username leaks via timing'; with djm@, original patches from solar
1814 lines
43 KiB
C
1814 lines
43 KiB
C
/*
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* Copyright 2002 Niels Provos <provos@citi.umich.edu>
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* Copyright 2002 Markus Friedl <markus@openbsd.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "includes.h"
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RCSID("$OpenBSD: monitor.c,v 1.49 2003/08/28 12:54:34 markus Exp $");
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#include <openssl/dh.h>
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#ifdef SKEY
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#include <skey.h>
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#endif
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#include "ssh.h"
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#include "auth.h"
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#include "kex.h"
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#include "dh.h"
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#include "zlib.h"
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#include "packet.h"
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#include "auth-options.h"
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#include "sshpty.h"
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#include "channels.h"
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#include "session.h"
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#include "sshlogin.h"
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#include "canohost.h"
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#include "log.h"
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#include "servconf.h"
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#include "monitor.h"
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#include "monitor_mm.h"
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#include "monitor_wrap.h"
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#include "monitor_fdpass.h"
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#include "xmalloc.h"
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#include "misc.h"
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#include "buffer.h"
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#include "bufaux.h"
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#include "compat.h"
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#include "ssh2.h"
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#include "mpaux.h"
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#ifdef GSSAPI
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#include "ssh-gss.h"
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static Gssctxt *gsscontext = NULL;
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#endif
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/* Imports */
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extern ServerOptions options;
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extern u_int utmp_len;
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extern Newkeys *current_keys[];
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extern z_stream incoming_stream;
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extern z_stream outgoing_stream;
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extern u_char session_id[];
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extern Buffer input, output;
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extern Buffer auth_debug;
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extern int auth_debug_init;
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/* State exported from the child */
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struct {
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z_stream incoming;
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z_stream outgoing;
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u_char *keyin;
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u_int keyinlen;
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u_char *keyout;
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u_int keyoutlen;
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u_char *ivin;
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u_int ivinlen;
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u_char *ivout;
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u_int ivoutlen;
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u_char *ssh1key;
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u_int ssh1keylen;
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int ssh1cipher;
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int ssh1protoflags;
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u_char *input;
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u_int ilen;
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u_char *output;
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u_int olen;
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} child_state;
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/* Functions on the monitor that answer unprivileged requests */
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int mm_answer_moduli(int, Buffer *);
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int mm_answer_sign(int, Buffer *);
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int mm_answer_pwnamallow(int, Buffer *);
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int mm_answer_auth2_read_banner(int, Buffer *);
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int mm_answer_authserv(int, Buffer *);
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int mm_answer_authpassword(int, Buffer *);
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int mm_answer_bsdauthquery(int, Buffer *);
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int mm_answer_bsdauthrespond(int, Buffer *);
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int mm_answer_skeyquery(int, Buffer *);
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int mm_answer_skeyrespond(int, Buffer *);
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int mm_answer_keyallowed(int, Buffer *);
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int mm_answer_keyverify(int, Buffer *);
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int mm_answer_pty(int, Buffer *);
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int mm_answer_pty_cleanup(int, Buffer *);
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int mm_answer_term(int, Buffer *);
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int mm_answer_rsa_keyallowed(int, Buffer *);
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int mm_answer_rsa_challenge(int, Buffer *);
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int mm_answer_rsa_response(int, Buffer *);
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int mm_answer_sesskey(int, Buffer *);
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int mm_answer_sessid(int, Buffer *);
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#ifdef USE_PAM
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int mm_answer_pam_start(int, Buffer *);
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int mm_answer_pam_account(int, Buffer *);
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int mm_answer_pam_init_ctx(int, Buffer *);
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int mm_answer_pam_query(int, Buffer *);
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int mm_answer_pam_respond(int, Buffer *);
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int mm_answer_pam_free_ctx(int, Buffer *);
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#endif
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#ifdef GSSAPI
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int mm_answer_gss_setup_ctx(int, Buffer *);
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int mm_answer_gss_accept_ctx(int, Buffer *);
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int mm_answer_gss_userok(int, Buffer *);
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#endif
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static Authctxt *authctxt;
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static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
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/* local state for key verify */
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static u_char *key_blob = NULL;
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static u_int key_bloblen = 0;
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static int key_blobtype = MM_NOKEY;
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static char *hostbased_cuser = NULL;
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static char *hostbased_chost = NULL;
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static char *auth_method = "unknown";
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static u_int session_id2_len = 0;
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static u_char *session_id2 = NULL;
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static pid_t monitor_child_pid;
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struct mon_table {
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enum monitor_reqtype type;
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int flags;
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int (*f)(int, Buffer *);
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};
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#define MON_ISAUTH 0x0004 /* Required for Authentication */
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#define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
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#define MON_ONCE 0x0010 /* Disable after calling */
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#define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
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#define MON_PERMIT 0x1000 /* Request is permitted */
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struct mon_table mon_dispatch_proto20[] = {
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{MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
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{MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
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{MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
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{MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
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{MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
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{MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
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#ifdef USE_PAM
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{MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start},
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{MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account},
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{MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx},
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{MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query},
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{MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond},
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{MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx},
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#endif
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#ifdef BSD_AUTH
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{MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
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{MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH,mm_answer_bsdauthrespond},
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#endif
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#ifdef SKEY
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{MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
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{MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
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#endif
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{MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
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{MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
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#ifdef GSSAPI
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{MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
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{MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
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{MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
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#endif
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{0, 0, NULL}
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};
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struct mon_table mon_dispatch_postauth20[] = {
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{MONITOR_REQ_MODULI, 0, mm_answer_moduli},
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{MONITOR_REQ_SIGN, 0, mm_answer_sign},
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{MONITOR_REQ_PTY, 0, mm_answer_pty},
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{MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
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{MONITOR_REQ_TERM, 0, mm_answer_term},
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{0, 0, NULL}
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};
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struct mon_table mon_dispatch_proto15[] = {
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{MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
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{MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
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{MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
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{MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
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{MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH, mm_answer_rsa_keyallowed},
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{MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
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{MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
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{MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
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#ifdef BSD_AUTH
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{MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
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{MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH,mm_answer_bsdauthrespond},
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#endif
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#ifdef SKEY
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{MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
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{MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
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#endif
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#ifdef USE_PAM
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{MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start},
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{MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account},
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{MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx},
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{MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query},
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{MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond},
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{MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx},
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#endif
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{0, 0, NULL}
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};
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struct mon_table mon_dispatch_postauth15[] = {
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{MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
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{MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
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{MONITOR_REQ_TERM, 0, mm_answer_term},
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{0, 0, NULL}
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};
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struct mon_table *mon_dispatch;
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/* Specifies if a certain message is allowed at the moment */
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static void
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monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
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{
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while (ent->f != NULL) {
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if (ent->type == type) {
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ent->flags &= ~MON_PERMIT;
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ent->flags |= permit ? MON_PERMIT : 0;
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return;
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}
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ent++;
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}
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}
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static void
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monitor_permit_authentications(int permit)
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{
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struct mon_table *ent = mon_dispatch;
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while (ent->f != NULL) {
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if (ent->flags & MON_AUTH) {
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ent->flags &= ~MON_PERMIT;
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ent->flags |= permit ? MON_PERMIT : 0;
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}
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ent++;
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}
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}
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Authctxt *
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monitor_child_preauth(struct monitor *pmonitor)
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{
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struct mon_table *ent;
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int authenticated = 0;
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debug3("preauth child monitor started");
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if (compat20) {
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mon_dispatch = mon_dispatch_proto20;
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/* Permit requests for moduli and signatures */
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monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
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monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
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} else {
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mon_dispatch = mon_dispatch_proto15;
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monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
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}
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authctxt = authctxt_new();
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/* The first few requests do not require asynchronous access */
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while (!authenticated) {
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authenticated = monitor_read(pmonitor, mon_dispatch, &ent);
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if (authenticated) {
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if (!(ent->flags & MON_AUTHDECIDE))
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fatal("%s: unexpected authentication from %d",
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__func__, ent->type);
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if (authctxt->pw->pw_uid == 0 &&
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!auth_root_allowed(auth_method))
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authenticated = 0;
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#ifdef USE_PAM
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/* PAM needs to perform account checks after auth */
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if (options.use_pam) {
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Buffer m;
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buffer_init(&m);
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mm_request_receive_expect(pmonitor->m_sendfd,
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MONITOR_REQ_PAM_ACCOUNT, &m);
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authenticated = mm_answer_pam_account(pmonitor->m_sendfd, &m);
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buffer_free(&m);
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}
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#endif
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}
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if (ent->flags & MON_AUTHDECIDE) {
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auth_log(authctxt, authenticated, auth_method,
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compat20 ? " ssh2" : "");
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if (!authenticated)
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authctxt->failures++;
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}
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}
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if (!authctxt->valid)
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fatal("%s: authenticated invalid user", __func__);
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debug("%s: %s has been authenticated by privileged process",
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__func__, authctxt->user);
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mm_get_keystate(pmonitor);
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return (authctxt);
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}
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static void
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monitor_set_child_handler(pid_t pid)
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{
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monitor_child_pid = pid;
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}
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static void
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monitor_child_handler(int signal)
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{
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kill(monitor_child_pid, signal);
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}
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void
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monitor_child_postauth(struct monitor *pmonitor)
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{
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monitor_set_child_handler(pmonitor->m_pid);
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signal(SIGHUP, &monitor_child_handler);
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signal(SIGTERM, &monitor_child_handler);
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if (compat20) {
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mon_dispatch = mon_dispatch_postauth20;
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/* Permit requests for moduli and signatures */
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monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
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monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
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monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
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} else {
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mon_dispatch = mon_dispatch_postauth15;
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monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
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}
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if (!no_pty_flag) {
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monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
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monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
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}
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for (;;)
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monitor_read(pmonitor, mon_dispatch, NULL);
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}
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void
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monitor_sync(struct monitor *pmonitor)
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{
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if (options.compression) {
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/* The member allocation is not visible, so sync it */
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mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
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}
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}
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int
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monitor_read(struct monitor *pmonitor, struct mon_table *ent,
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struct mon_table **pent)
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{
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Buffer m;
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int ret;
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u_char type;
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buffer_init(&m);
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mm_request_receive(pmonitor->m_sendfd, &m);
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type = buffer_get_char(&m);
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debug3("%s: checking request %d", __func__, type);
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while (ent->f != NULL) {
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if (ent->type == type)
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break;
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ent++;
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}
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if (ent->f != NULL) {
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if (!(ent->flags & MON_PERMIT))
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fatal("%s: unpermitted request %d", __func__,
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type);
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ret = (*ent->f)(pmonitor->m_sendfd, &m);
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buffer_free(&m);
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/* The child may use this request only once, disable it */
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if (ent->flags & MON_ONCE) {
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debug2("%s: %d used once, disabling now", __func__,
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type);
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ent->flags &= ~MON_PERMIT;
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}
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if (pent != NULL)
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*pent = ent;
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return ret;
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}
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fatal("%s: unsupported request: %d", __func__, type);
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/* NOTREACHED */
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return (-1);
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}
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/* allowed key state */
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static int
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monitor_allowed_key(u_char *blob, u_int bloblen)
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{
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/* make sure key is allowed */
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if (key_blob == NULL || key_bloblen != bloblen ||
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memcmp(key_blob, blob, key_bloblen))
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return (0);
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return (1);
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}
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static void
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monitor_reset_key_state(void)
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{
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/* reset state */
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if (key_blob != NULL)
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xfree(key_blob);
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if (hostbased_cuser != NULL)
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xfree(hostbased_cuser);
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if (hostbased_chost != NULL)
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xfree(hostbased_chost);
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key_blob = NULL;
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key_bloblen = 0;
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key_blobtype = MM_NOKEY;
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hostbased_cuser = NULL;
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hostbased_chost = NULL;
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}
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int
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mm_answer_moduli(int socket, Buffer *m)
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{
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DH *dh;
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int min, want, max;
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min = buffer_get_int(m);
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want = buffer_get_int(m);
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max = buffer_get_int(m);
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debug3("%s: got parameters: %d %d %d",
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__func__, min, want, max);
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/* We need to check here, too, in case the child got corrupted */
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if (max < min || want < min || max < want)
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fatal("%s: bad parameters: %d %d %d",
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__func__, min, want, max);
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|
|
buffer_clear(m);
|
|
|
|
dh = choose_dh(min, want, max);
|
|
if (dh == NULL) {
|
|
buffer_put_char(m, 0);
|
|
return (0);
|
|
} else {
|
|
/* Send first bignum */
|
|
buffer_put_char(m, 1);
|
|
buffer_put_bignum2(m, dh->p);
|
|
buffer_put_bignum2(m, dh->g);
|
|
|
|
DH_free(dh);
|
|
}
|
|
mm_request_send(socket, MONITOR_ANS_MODULI, m);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_sign(int socket, Buffer *m)
|
|
{
|
|
Key *key;
|
|
u_char *p;
|
|
u_char *signature;
|
|
u_int siglen, datlen;
|
|
int keyid;
|
|
|
|
debug3("%s", __func__);
|
|
|
|
keyid = buffer_get_int(m);
|
|
p = buffer_get_string(m, &datlen);
|
|
|
|
if (datlen != 20)
|
|
fatal("%s: data length incorrect: %u", __func__, datlen);
|
|
|
|
/* save session id, it will be passed on the first call */
|
|
if (session_id2_len == 0) {
|
|
session_id2_len = datlen;
|
|
session_id2 = xmalloc(session_id2_len);
|
|
memcpy(session_id2, p, session_id2_len);
|
|
}
|
|
|
|
if ((key = get_hostkey_by_index(keyid)) == NULL)
|
|
fatal("%s: no hostkey from index %d", __func__, keyid);
|
|
if (key_sign(key, &signature, &siglen, p, datlen) < 0)
|
|
fatal("%s: key_sign failed", __func__);
|
|
|
|
debug3("%s: signature %p(%u)", __func__, signature, siglen);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_string(m, signature, siglen);
|
|
|
|
xfree(p);
|
|
xfree(signature);
|
|
|
|
mm_request_send(socket, MONITOR_ANS_SIGN, m);
|
|
|
|
/* Turn on permissions for getpwnam */
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/* Retrieves the password entry and also checks if the user is permitted */
|
|
|
|
int
|
|
mm_answer_pwnamallow(int socket, Buffer *m)
|
|
{
|
|
char *login;
|
|
struct passwd *pwent;
|
|
int allowed = 0;
|
|
|
|
debug3("%s", __func__);
|
|
|
|
if (authctxt->attempt++ != 0)
|
|
fatal("%s: multiple attempts for getpwnam", __func__);
|
|
|
|
login = buffer_get_string(m, NULL);
|
|
|
|
pwent = getpwnamallow(login);
|
|
|
|
authctxt->user = xstrdup(login);
|
|
setproctitle("%s [priv]", pwent ? login : "unknown");
|
|
xfree(login);
|
|
|
|
buffer_clear(m);
|
|
|
|
if (pwent == NULL) {
|
|
buffer_put_char(m, 0);
|
|
goto out;
|
|
}
|
|
|
|
allowed = 1;
|
|
authctxt->pw = pwent;
|
|
authctxt->valid = 1;
|
|
|
|
buffer_put_char(m, 1);
|
|
buffer_put_string(m, pwent, sizeof(struct passwd));
|
|
buffer_put_cstring(m, pwent->pw_name);
|
|
buffer_put_cstring(m, "*");
|
|
buffer_put_cstring(m, pwent->pw_gecos);
|
|
#ifdef HAVE_PW_CLASS_IN_PASSWD
|
|
buffer_put_cstring(m, pwent->pw_class);
|
|
#endif
|
|
buffer_put_cstring(m, pwent->pw_dir);
|
|
buffer_put_cstring(m, pwent->pw_shell);
|
|
|
|
out:
|
|
debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
|
|
mm_request_send(socket, MONITOR_ANS_PWNAM, m);
|
|
|
|
/* For SSHv1 allow authentication now */
|
|
if (!compat20)
|
|
monitor_permit_authentications(1);
|
|
else {
|
|
/* Allow service/style information on the auth context */
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
|
|
}
|
|
|
|
#ifdef USE_PAM
|
|
if (options.use_pam)
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_PAM_START, 1);
|
|
#endif
|
|
|
|
return (0);
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
int
|
|
mm_answer_authserv(int socket, Buffer *m)
|
|
{
|
|
monitor_permit_authentications(1);
|
|
|
|
authctxt->service = buffer_get_string(m, NULL);
|
|
authctxt->style = buffer_get_string(m, NULL);
|
|
debug3("%s: service=%s, style=%s",
|
|
__func__, authctxt->service, authctxt->style);
|
|
|
|
if (strlen(authctxt->style) == 0) {
|
|
xfree(authctxt->style);
|
|
authctxt->style = NULL;
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_authpassword(int socket, Buffer *m)
|
|
{
|
|
static int call_count;
|
|
char *passwd;
|
|
int authenticated;
|
|
u_int plen;
|
|
|
|
passwd = buffer_get_string(m, &plen);
|
|
/* Only authenticate if the context is valid */
|
|
authenticated = options.password_authentication &&
|
|
auth_password(authctxt, passwd);
|
|
memset(passwd, 0, strlen(passwd));
|
|
xfree(passwd);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, authenticated);
|
|
|
|
debug3("%s: sending result %d", __func__, authenticated);
|
|
mm_request_send(socket, MONITOR_ANS_AUTHPASSWORD, m);
|
|
|
|
call_count++;
|
|
if (plen == 0 && call_count == 1)
|
|
auth_method = "none";
|
|
else
|
|
auth_method = "password";
|
|
|
|
/* Causes monitor loop to terminate if authenticated */
|
|
return (authenticated);
|
|
}
|
|
|
|
#ifdef BSD_AUTH
|
|
int
|
|
mm_answer_bsdauthquery(int socket, Buffer *m)
|
|
{
|
|
char *name, *infotxt;
|
|
u_int numprompts;
|
|
u_int *echo_on;
|
|
char **prompts;
|
|
u_int success;
|
|
|
|
success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
|
|
&prompts, &echo_on) < 0 ? 0 : 1;
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, success);
|
|
if (success)
|
|
buffer_put_cstring(m, prompts[0]);
|
|
|
|
debug3("%s: sending challenge success: %u", __func__, success);
|
|
mm_request_send(socket, MONITOR_ANS_BSDAUTHQUERY, m);
|
|
|
|
if (success) {
|
|
xfree(name);
|
|
xfree(infotxt);
|
|
xfree(prompts);
|
|
xfree(echo_on);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_bsdauthrespond(int socket, Buffer *m)
|
|
{
|
|
char *response;
|
|
int authok;
|
|
|
|
if (authctxt->as == 0)
|
|
fatal("%s: no bsd auth session", __func__);
|
|
|
|
response = buffer_get_string(m, NULL);
|
|
authok = options.challenge_response_authentication &&
|
|
auth_userresponse(authctxt->as, response, 0);
|
|
authctxt->as = NULL;
|
|
debug3("%s: <%s> = <%d>", __func__, response, authok);
|
|
xfree(response);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, authok);
|
|
|
|
debug3("%s: sending authenticated: %d", __func__, authok);
|
|
mm_request_send(socket, MONITOR_ANS_BSDAUTHRESPOND, m);
|
|
|
|
auth_method = "bsdauth";
|
|
|
|
return (authok != 0);
|
|
}
|
|
#endif
|
|
|
|
#ifdef SKEY
|
|
int
|
|
mm_answer_skeyquery(int socket, Buffer *m)
|
|
{
|
|
struct skey skey;
|
|
char challenge[1024];
|
|
u_int success;
|
|
|
|
success = skeychallenge(&skey, authctxt->user, challenge) < 0 ? 0 : 1;
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, success);
|
|
if (success)
|
|
buffer_put_cstring(m, challenge);
|
|
|
|
debug3("%s: sending challenge success: %u", __func__, success);
|
|
mm_request_send(socket, MONITOR_ANS_SKEYQUERY, m);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_skeyrespond(int socket, Buffer *m)
|
|
{
|
|
char *response;
|
|
int authok;
|
|
|
|
response = buffer_get_string(m, NULL);
|
|
|
|
authok = (options.challenge_response_authentication &&
|
|
authctxt->valid &&
|
|
skey_haskey(authctxt->pw->pw_name) == 0 &&
|
|
skey_passcheck(authctxt->pw->pw_name, response) != -1);
|
|
|
|
xfree(response);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, authok);
|
|
|
|
debug3("%s: sending authenticated: %d", __func__, authok);
|
|
mm_request_send(socket, MONITOR_ANS_SKEYRESPOND, m);
|
|
|
|
auth_method = "skey";
|
|
|
|
return (authok != 0);
|
|
}
|
|
#endif
|
|
|
|
#ifdef USE_PAM
|
|
int
|
|
mm_answer_pam_start(int socket, Buffer *m)
|
|
{
|
|
char *user;
|
|
|
|
if (!options.use_pam)
|
|
fatal("UsePAM not set, but ended up in %s anyway", __func__);
|
|
|
|
user = buffer_get_string(m, NULL);
|
|
|
|
start_pam(user);
|
|
|
|
xfree(user);
|
|
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_PAM_ACCOUNT, 1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_pam_account(int socket, Buffer *m)
|
|
{
|
|
u_int ret;
|
|
|
|
if (!options.use_pam)
|
|
fatal("UsePAM not set, but ended up in %s anyway", __func__);
|
|
|
|
ret = do_pam_account();
|
|
|
|
buffer_put_int(m, ret);
|
|
|
|
mm_request_send(socket, MONITOR_ANS_PAM_ACCOUNT, m);
|
|
|
|
return (ret);
|
|
}
|
|
|
|
static void *sshpam_ctxt, *sshpam_authok;
|
|
extern KbdintDevice sshpam_device;
|
|
|
|
int
|
|
mm_answer_pam_init_ctx(int socket, Buffer *m)
|
|
{
|
|
|
|
debug3("%s", __func__);
|
|
authctxt->user = buffer_get_string(m, NULL);
|
|
sshpam_ctxt = (sshpam_device.init_ctx)(authctxt);
|
|
sshpam_authok = NULL;
|
|
buffer_clear(m);
|
|
if (sshpam_ctxt != NULL) {
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_PAM_FREE_CTX, 1);
|
|
buffer_put_int(m, 1);
|
|
} else {
|
|
buffer_put_int(m, 0);
|
|
}
|
|
mm_request_send(socket, MONITOR_ANS_PAM_INIT_CTX, m);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_pam_query(int socket, Buffer *m)
|
|
{
|
|
char *name, *info, **prompts;
|
|
u_int num, *echo_on;
|
|
int i, ret;
|
|
|
|
debug3("%s", __func__);
|
|
sshpam_authok = NULL;
|
|
ret = (sshpam_device.query)(sshpam_ctxt, &name, &info, &num, &prompts, &echo_on);
|
|
if (ret == 0 && num == 0)
|
|
sshpam_authok = sshpam_ctxt;
|
|
if (num > 1 || name == NULL || info == NULL)
|
|
ret = -1;
|
|
buffer_clear(m);
|
|
buffer_put_int(m, ret);
|
|
buffer_put_cstring(m, name);
|
|
xfree(name);
|
|
buffer_put_cstring(m, info);
|
|
xfree(info);
|
|
buffer_put_int(m, num);
|
|
for (i = 0; i < num; ++i) {
|
|
buffer_put_cstring(m, prompts[i]);
|
|
xfree(prompts[i]);
|
|
buffer_put_int(m, echo_on[i]);
|
|
}
|
|
if (prompts != NULL)
|
|
xfree(prompts);
|
|
if (echo_on != NULL)
|
|
xfree(echo_on);
|
|
mm_request_send(socket, MONITOR_ANS_PAM_QUERY, m);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_pam_respond(int socket, Buffer *m)
|
|
{
|
|
char **resp;
|
|
u_int num;
|
|
int i, ret;
|
|
|
|
debug3("%s", __func__);
|
|
sshpam_authok = NULL;
|
|
num = buffer_get_int(m);
|
|
if (num > 0) {
|
|
resp = xmalloc(num * sizeof(char *));
|
|
for (i = 0; i < num; ++i)
|
|
resp[i] = buffer_get_string(m, NULL);
|
|
ret = (sshpam_device.respond)(sshpam_ctxt, num, resp);
|
|
for (i = 0; i < num; ++i)
|
|
xfree(resp[i]);
|
|
xfree(resp);
|
|
} else {
|
|
ret = (sshpam_device.respond)(sshpam_ctxt, num, NULL);
|
|
}
|
|
buffer_clear(m);
|
|
buffer_put_int(m, ret);
|
|
mm_request_send(socket, MONITOR_ANS_PAM_RESPOND, m);
|
|
auth_method = "keyboard-interactive/pam";
|
|
if (ret == 0)
|
|
sshpam_authok = sshpam_ctxt;
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_pam_free_ctx(int socket, Buffer *m)
|
|
{
|
|
|
|
debug3("%s", __func__);
|
|
(sshpam_device.free_ctx)(sshpam_ctxt);
|
|
buffer_clear(m);
|
|
mm_request_send(socket, MONITOR_ANS_PAM_FREE_CTX, m);
|
|
return (sshpam_authok == sshpam_ctxt);
|
|
}
|
|
#endif
|
|
|
|
static void
|
|
mm_append_debug(Buffer *m)
|
|
{
|
|
if (auth_debug_init && buffer_len(&auth_debug)) {
|
|
debug3("%s: Appending debug messages for child", __func__);
|
|
buffer_append(m, buffer_ptr(&auth_debug),
|
|
buffer_len(&auth_debug));
|
|
buffer_clear(&auth_debug);
|
|
}
|
|
}
|
|
|
|
int
|
|
mm_answer_keyallowed(int socket, Buffer *m)
|
|
{
|
|
Key *key;
|
|
char *cuser, *chost;
|
|
u_char *blob;
|
|
u_int bloblen;
|
|
enum mm_keytype type = 0;
|
|
int allowed = 0;
|
|
|
|
debug3("%s entering", __func__);
|
|
|
|
type = buffer_get_int(m);
|
|
cuser = buffer_get_string(m, NULL);
|
|
chost = buffer_get_string(m, NULL);
|
|
blob = buffer_get_string(m, &bloblen);
|
|
|
|
key = key_from_blob(blob, bloblen);
|
|
|
|
if ((compat20 && type == MM_RSAHOSTKEY) ||
|
|
(!compat20 && type != MM_RSAHOSTKEY))
|
|
fatal("%s: key type and protocol mismatch", __func__);
|
|
|
|
debug3("%s: key_from_blob: %p", __func__, key);
|
|
|
|
if (key != NULL && authctxt->pw != NULL) {
|
|
switch(type) {
|
|
case MM_USERKEY:
|
|
allowed = options.pubkey_authentication &&
|
|
user_key_allowed(authctxt->pw, key);
|
|
break;
|
|
case MM_HOSTKEY:
|
|
allowed = options.hostbased_authentication &&
|
|
hostbased_key_allowed(authctxt->pw,
|
|
cuser, chost, key);
|
|
break;
|
|
case MM_RSAHOSTKEY:
|
|
key->type = KEY_RSA1; /* XXX */
|
|
allowed = options.rhosts_rsa_authentication &&
|
|
auth_rhosts_rsa_key_allowed(authctxt->pw,
|
|
cuser, chost, key);
|
|
break;
|
|
default:
|
|
fatal("%s: unknown key type %d", __func__, type);
|
|
break;
|
|
}
|
|
}
|
|
if (key != NULL)
|
|
key_free(key);
|
|
|
|
/* clear temporarily storage (used by verify) */
|
|
monitor_reset_key_state();
|
|
|
|
if (allowed) {
|
|
/* Save temporarily for comparison in verify */
|
|
key_blob = blob;
|
|
key_bloblen = bloblen;
|
|
key_blobtype = type;
|
|
hostbased_cuser = cuser;
|
|
hostbased_chost = chost;
|
|
}
|
|
|
|
debug3("%s: key %p is %s",
|
|
__func__, key, allowed ? "allowed" : "disallowed");
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, allowed);
|
|
buffer_put_int(m, forced_command != NULL);
|
|
|
|
mm_append_debug(m);
|
|
|
|
mm_request_send(socket, MONITOR_ANS_KEYALLOWED, m);
|
|
|
|
if (type == MM_RSAHOSTKEY)
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
monitor_valid_userblob(u_char *data, u_int datalen)
|
|
{
|
|
Buffer b;
|
|
char *p;
|
|
u_int len;
|
|
int fail = 0;
|
|
|
|
buffer_init(&b);
|
|
buffer_append(&b, data, datalen);
|
|
|
|
if (datafellows & SSH_OLD_SESSIONID) {
|
|
p = buffer_ptr(&b);
|
|
len = buffer_len(&b);
|
|
if ((session_id2 == NULL) ||
|
|
(len < session_id2_len) ||
|
|
(memcmp(p, session_id2, session_id2_len) != 0))
|
|
fail++;
|
|
buffer_consume(&b, session_id2_len);
|
|
} else {
|
|
p = buffer_get_string(&b, &len);
|
|
if ((session_id2 == NULL) ||
|
|
(len != session_id2_len) ||
|
|
(memcmp(p, session_id2, session_id2_len) != 0))
|
|
fail++;
|
|
xfree(p);
|
|
}
|
|
if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
|
|
fail++;
|
|
p = buffer_get_string(&b, NULL);
|
|
if (strcmp(authctxt->user, p) != 0) {
|
|
logit("wrong user name passed to monitor: expected %s != %.100s",
|
|
authctxt->user, p);
|
|
fail++;
|
|
}
|
|
xfree(p);
|
|
buffer_skip_string(&b);
|
|
if (datafellows & SSH_BUG_PKAUTH) {
|
|
if (!buffer_get_char(&b))
|
|
fail++;
|
|
} else {
|
|
p = buffer_get_string(&b, NULL);
|
|
if (strcmp("publickey", p) != 0)
|
|
fail++;
|
|
xfree(p);
|
|
if (!buffer_get_char(&b))
|
|
fail++;
|
|
buffer_skip_string(&b);
|
|
}
|
|
buffer_skip_string(&b);
|
|
if (buffer_len(&b) != 0)
|
|
fail++;
|
|
buffer_free(&b);
|
|
return (fail == 0);
|
|
}
|
|
|
|
static int
|
|
monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
|
|
char *chost)
|
|
{
|
|
Buffer b;
|
|
char *p;
|
|
u_int len;
|
|
int fail = 0;
|
|
|
|
buffer_init(&b);
|
|
buffer_append(&b, data, datalen);
|
|
|
|
p = buffer_get_string(&b, &len);
|
|
if ((session_id2 == NULL) ||
|
|
(len != session_id2_len) ||
|
|
(memcmp(p, session_id2, session_id2_len) != 0))
|
|
fail++;
|
|
xfree(p);
|
|
|
|
if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
|
|
fail++;
|
|
p = buffer_get_string(&b, NULL);
|
|
if (strcmp(authctxt->user, p) != 0) {
|
|
logit("wrong user name passed to monitor: expected %s != %.100s",
|
|
authctxt->user, p);
|
|
fail++;
|
|
}
|
|
xfree(p);
|
|
buffer_skip_string(&b); /* service */
|
|
p = buffer_get_string(&b, NULL);
|
|
if (strcmp(p, "hostbased") != 0)
|
|
fail++;
|
|
xfree(p);
|
|
buffer_skip_string(&b); /* pkalg */
|
|
buffer_skip_string(&b); /* pkblob */
|
|
|
|
/* verify client host, strip trailing dot if necessary */
|
|
p = buffer_get_string(&b, NULL);
|
|
if (((len = strlen(p)) > 0) && p[len - 1] == '.')
|
|
p[len - 1] = '\0';
|
|
if (strcmp(p, chost) != 0)
|
|
fail++;
|
|
xfree(p);
|
|
|
|
/* verify client user */
|
|
p = buffer_get_string(&b, NULL);
|
|
if (strcmp(p, cuser) != 0)
|
|
fail++;
|
|
xfree(p);
|
|
|
|
if (buffer_len(&b) != 0)
|
|
fail++;
|
|
buffer_free(&b);
|
|
return (fail == 0);
|
|
}
|
|
|
|
int
|
|
mm_answer_keyverify(int socket, Buffer *m)
|
|
{
|
|
Key *key;
|
|
u_char *signature, *data, *blob;
|
|
u_int signaturelen, datalen, bloblen;
|
|
int verified = 0;
|
|
int valid_data = 0;
|
|
|
|
blob = buffer_get_string(m, &bloblen);
|
|
signature = buffer_get_string(m, &signaturelen);
|
|
data = buffer_get_string(m, &datalen);
|
|
|
|
if (hostbased_cuser == NULL || hostbased_chost == NULL ||
|
|
!monitor_allowed_key(blob, bloblen))
|
|
fatal("%s: bad key, not previously allowed", __func__);
|
|
|
|
key = key_from_blob(blob, bloblen);
|
|
if (key == NULL)
|
|
fatal("%s: bad public key blob", __func__);
|
|
|
|
switch (key_blobtype) {
|
|
case MM_USERKEY:
|
|
valid_data = monitor_valid_userblob(data, datalen);
|
|
break;
|
|
case MM_HOSTKEY:
|
|
valid_data = monitor_valid_hostbasedblob(data, datalen,
|
|
hostbased_cuser, hostbased_chost);
|
|
break;
|
|
default:
|
|
valid_data = 0;
|
|
break;
|
|
}
|
|
if (!valid_data)
|
|
fatal("%s: bad signature data blob", __func__);
|
|
|
|
verified = key_verify(key, signature, signaturelen, data, datalen);
|
|
debug3("%s: key %p signature %s",
|
|
__func__, key, verified ? "verified" : "unverified");
|
|
|
|
key_free(key);
|
|
xfree(blob);
|
|
xfree(signature);
|
|
xfree(data);
|
|
|
|
auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
|
|
|
|
monitor_reset_key_state();
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, verified);
|
|
mm_request_send(socket, MONITOR_ANS_KEYVERIFY, m);
|
|
|
|
return (verified);
|
|
}
|
|
|
|
static void
|
|
mm_record_login(Session *s, struct passwd *pw)
|
|
{
|
|
socklen_t fromlen;
|
|
struct sockaddr_storage from;
|
|
|
|
/*
|
|
* Get IP address of client. If the connection is not a socket, let
|
|
* the address be 0.0.0.0.
|
|
*/
|
|
memset(&from, 0, sizeof(from));
|
|
fromlen = sizeof(from);
|
|
if (packet_connection_is_on_socket()) {
|
|
if (getpeername(packet_get_connection_in(),
|
|
(struct sockaddr *) & from, &fromlen) < 0) {
|
|
debug("getpeername: %.100s", strerror(errno));
|
|
fatal_cleanup();
|
|
}
|
|
}
|
|
/* Record that there was a login on that tty from the remote host. */
|
|
record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
|
|
get_remote_name_or_ip(utmp_len, options.use_dns),
|
|
(struct sockaddr *)&from, fromlen);
|
|
}
|
|
|
|
static void
|
|
mm_session_close(Session *s)
|
|
{
|
|
debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
|
|
if (s->ttyfd != -1) {
|
|
debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
|
|
fatal_remove_cleanup(session_pty_cleanup2, (void *)s);
|
|
session_pty_cleanup2(s);
|
|
}
|
|
s->used = 0;
|
|
}
|
|
|
|
int
|
|
mm_answer_pty(int socket, Buffer *m)
|
|
{
|
|
extern struct monitor *pmonitor;
|
|
Session *s;
|
|
int res, fd0;
|
|
|
|
debug3("%s entering", __func__);
|
|
|
|
buffer_clear(m);
|
|
s = session_new();
|
|
if (s == NULL)
|
|
goto error;
|
|
s->authctxt = authctxt;
|
|
s->pw = authctxt->pw;
|
|
s->pid = pmonitor->m_pid;
|
|
res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
|
|
if (res == 0)
|
|
goto error;
|
|
fatal_add_cleanup(session_pty_cleanup2, (void *)s);
|
|
pty_setowner(authctxt->pw, s->tty);
|
|
|
|
buffer_put_int(m, 1);
|
|
buffer_put_cstring(m, s->tty);
|
|
mm_request_send(socket, MONITOR_ANS_PTY, m);
|
|
|
|
mm_send_fd(socket, s->ptyfd);
|
|
mm_send_fd(socket, s->ttyfd);
|
|
|
|
/* We need to trick ttyslot */
|
|
if (dup2(s->ttyfd, 0) == -1)
|
|
fatal("%s: dup2", __func__);
|
|
|
|
mm_record_login(s, authctxt->pw);
|
|
|
|
/* Now we can close the file descriptor again */
|
|
close(0);
|
|
|
|
/* make sure nothing uses fd 0 */
|
|
if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
|
|
fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
|
|
if (fd0 != 0)
|
|
error("%s: fd0 %d != 0", __func__, fd0);
|
|
|
|
/* slave is not needed */
|
|
close(s->ttyfd);
|
|
s->ttyfd = s->ptyfd;
|
|
/* no need to dup() because nobody closes ptyfd */
|
|
s->ptymaster = s->ptyfd;
|
|
|
|
debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
|
|
|
|
return (0);
|
|
|
|
error:
|
|
if (s != NULL)
|
|
mm_session_close(s);
|
|
buffer_put_int(m, 0);
|
|
mm_request_send(socket, MONITOR_ANS_PTY, m);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_pty_cleanup(int socket, Buffer *m)
|
|
{
|
|
Session *s;
|
|
char *tty;
|
|
|
|
debug3("%s entering", __func__);
|
|
|
|
tty = buffer_get_string(m, NULL);
|
|
if ((s = session_by_tty(tty)) != NULL)
|
|
mm_session_close(s);
|
|
buffer_clear(m);
|
|
xfree(tty);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_sesskey(int socket, Buffer *m)
|
|
{
|
|
BIGNUM *p;
|
|
int rsafail;
|
|
|
|
/* Turn off permissions */
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
|
|
|
|
if ((p = BN_new()) == NULL)
|
|
fatal("%s: BN_new", __func__);
|
|
|
|
buffer_get_bignum2(m, p);
|
|
|
|
rsafail = ssh1_session_key(p);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, rsafail);
|
|
buffer_put_bignum2(m, p);
|
|
|
|
BN_clear_free(p);
|
|
|
|
mm_request_send(socket, MONITOR_ANS_SESSKEY, m);
|
|
|
|
/* Turn on permissions for sessid passing */
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_sessid(int socket, Buffer *m)
|
|
{
|
|
int i;
|
|
|
|
debug3("%s entering", __func__);
|
|
|
|
if (buffer_len(m) != 16)
|
|
fatal("%s: bad ssh1 session id", __func__);
|
|
for (i = 0; i < 16; i++)
|
|
session_id[i] = buffer_get_char(m);
|
|
|
|
/* Turn on permissions for getpwnam */
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_rsa_keyallowed(int socket, Buffer *m)
|
|
{
|
|
BIGNUM *client_n;
|
|
Key *key = NULL;
|
|
u_char *blob = NULL;
|
|
u_int blen = 0;
|
|
int allowed = 0;
|
|
|
|
debug3("%s entering", __func__);
|
|
|
|
if (options.rsa_authentication && authctxt->valid) {
|
|
if ((client_n = BN_new()) == NULL)
|
|
fatal("%s: BN_new", __func__);
|
|
buffer_get_bignum2(m, client_n);
|
|
allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
|
|
BN_clear_free(client_n);
|
|
}
|
|
buffer_clear(m);
|
|
buffer_put_int(m, allowed);
|
|
buffer_put_int(m, forced_command != NULL);
|
|
|
|
/* clear temporarily storage (used by generate challenge) */
|
|
monitor_reset_key_state();
|
|
|
|
if (allowed && key != NULL) {
|
|
key->type = KEY_RSA; /* cheat for key_to_blob */
|
|
if (key_to_blob(key, &blob, &blen) == 0)
|
|
fatal("%s: key_to_blob failed", __func__);
|
|
buffer_put_string(m, blob, blen);
|
|
|
|
/* Save temporarily for comparison in verify */
|
|
key_blob = blob;
|
|
key_bloblen = blen;
|
|
key_blobtype = MM_RSAUSERKEY;
|
|
}
|
|
if (key != NULL)
|
|
key_free(key);
|
|
|
|
mm_append_debug(m);
|
|
|
|
mm_request_send(socket, MONITOR_ANS_RSAKEYALLOWED, m);
|
|
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_rsa_challenge(int socket, Buffer *m)
|
|
{
|
|
Key *key = NULL;
|
|
u_char *blob;
|
|
u_int blen;
|
|
|
|
debug3("%s entering", __func__);
|
|
|
|
if (!authctxt->valid)
|
|
fatal("%s: authctxt not valid", __func__);
|
|
blob = buffer_get_string(m, &blen);
|
|
if (!monitor_allowed_key(blob, blen))
|
|
fatal("%s: bad key, not previously allowed", __func__);
|
|
if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
|
|
fatal("%s: key type mismatch", __func__);
|
|
if ((key = key_from_blob(blob, blen)) == NULL)
|
|
fatal("%s: received bad key", __func__);
|
|
|
|
if (ssh1_challenge)
|
|
BN_clear_free(ssh1_challenge);
|
|
ssh1_challenge = auth_rsa_generate_challenge(key);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_bignum2(m, ssh1_challenge);
|
|
|
|
debug3("%s sending reply", __func__);
|
|
mm_request_send(socket, MONITOR_ANS_RSACHALLENGE, m);
|
|
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
|
|
|
|
xfree(blob);
|
|
key_free(key);
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_rsa_response(int socket, Buffer *m)
|
|
{
|
|
Key *key = NULL;
|
|
u_char *blob, *response;
|
|
u_int blen, len;
|
|
int success;
|
|
|
|
debug3("%s entering", __func__);
|
|
|
|
if (!authctxt->valid)
|
|
fatal("%s: authctxt not valid", __func__);
|
|
if (ssh1_challenge == NULL)
|
|
fatal("%s: no ssh1_challenge", __func__);
|
|
|
|
blob = buffer_get_string(m, &blen);
|
|
if (!monitor_allowed_key(blob, blen))
|
|
fatal("%s: bad key, not previously allowed", __func__);
|
|
if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
|
|
fatal("%s: key type mismatch: %d", __func__, key_blobtype);
|
|
if ((key = key_from_blob(blob, blen)) == NULL)
|
|
fatal("%s: received bad key", __func__);
|
|
response = buffer_get_string(m, &len);
|
|
if (len != 16)
|
|
fatal("%s: received bad response to challenge", __func__);
|
|
success = auth_rsa_verify_response(key, ssh1_challenge, response);
|
|
|
|
xfree(blob);
|
|
key_free(key);
|
|
xfree(response);
|
|
|
|
auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
|
|
|
|
/* reset state */
|
|
BN_clear_free(ssh1_challenge);
|
|
ssh1_challenge = NULL;
|
|
monitor_reset_key_state();
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, success);
|
|
mm_request_send(socket, MONITOR_ANS_RSARESPONSE, m);
|
|
|
|
return (success);
|
|
}
|
|
|
|
int
|
|
mm_answer_term(int socket, Buffer *req)
|
|
{
|
|
extern struct monitor *pmonitor;
|
|
int res, status;
|
|
|
|
debug3("%s: tearing down sessions", __func__);
|
|
|
|
/* The child is terminating */
|
|
session_destroy_all(&mm_session_close);
|
|
|
|
while (waitpid(pmonitor->m_pid, &status, 0) == -1)
|
|
if (errno != EINTR)
|
|
exit(1);
|
|
|
|
res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
|
|
|
|
/* Terminate process */
|
|
exit (res);
|
|
}
|
|
|
|
void
|
|
monitor_apply_keystate(struct monitor *pmonitor)
|
|
{
|
|
if (compat20) {
|
|
set_newkeys(MODE_IN);
|
|
set_newkeys(MODE_OUT);
|
|
} else {
|
|
packet_set_protocol_flags(child_state.ssh1protoflags);
|
|
packet_set_encryption_key(child_state.ssh1key,
|
|
child_state.ssh1keylen, child_state.ssh1cipher);
|
|
xfree(child_state.ssh1key);
|
|
}
|
|
|
|
/* for rc4 and other stateful ciphers */
|
|
packet_set_keycontext(MODE_OUT, child_state.keyout);
|
|
xfree(child_state.keyout);
|
|
packet_set_keycontext(MODE_IN, child_state.keyin);
|
|
xfree(child_state.keyin);
|
|
|
|
if (!compat20) {
|
|
packet_set_iv(MODE_OUT, child_state.ivout);
|
|
xfree(child_state.ivout);
|
|
packet_set_iv(MODE_IN, child_state.ivin);
|
|
xfree(child_state.ivin);
|
|
}
|
|
|
|
memcpy(&incoming_stream, &child_state.incoming,
|
|
sizeof(incoming_stream));
|
|
memcpy(&outgoing_stream, &child_state.outgoing,
|
|
sizeof(outgoing_stream));
|
|
|
|
/* Update with new address */
|
|
if (options.compression)
|
|
mm_init_compression(pmonitor->m_zlib);
|
|
|
|
/* Network I/O buffers */
|
|
/* XXX inefficient for large buffers, need: buffer_init_from_string */
|
|
buffer_clear(&input);
|
|
buffer_append(&input, child_state.input, child_state.ilen);
|
|
memset(child_state.input, 0, child_state.ilen);
|
|
xfree(child_state.input);
|
|
|
|
buffer_clear(&output);
|
|
buffer_append(&output, child_state.output, child_state.olen);
|
|
memset(child_state.output, 0, child_state.olen);
|
|
xfree(child_state.output);
|
|
}
|
|
|
|
static Kex *
|
|
mm_get_kex(Buffer *m)
|
|
{
|
|
Kex *kex;
|
|
void *blob;
|
|
u_int bloblen;
|
|
|
|
kex = xmalloc(sizeof(*kex));
|
|
memset(kex, 0, sizeof(*kex));
|
|
kex->session_id = buffer_get_string(m, &kex->session_id_len);
|
|
if ((session_id2 == NULL) ||
|
|
(kex->session_id_len != session_id2_len) ||
|
|
(memcmp(kex->session_id, session_id2, session_id2_len) != 0))
|
|
fatal("mm_get_get: internal error: bad session id");
|
|
kex->we_need = buffer_get_int(m);
|
|
kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
|
|
kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
|
|
kex->server = 1;
|
|
kex->hostkey_type = buffer_get_int(m);
|
|
kex->kex_type = buffer_get_int(m);
|
|
blob = buffer_get_string(m, &bloblen);
|
|
buffer_init(&kex->my);
|
|
buffer_append(&kex->my, blob, bloblen);
|
|
xfree(blob);
|
|
blob = buffer_get_string(m, &bloblen);
|
|
buffer_init(&kex->peer);
|
|
buffer_append(&kex->peer, blob, bloblen);
|
|
xfree(blob);
|
|
kex->done = 1;
|
|
kex->flags = buffer_get_int(m);
|
|
kex->client_version_string = buffer_get_string(m, NULL);
|
|
kex->server_version_string = buffer_get_string(m, NULL);
|
|
kex->load_host_key=&get_hostkey_by_type;
|
|
kex->host_key_index=&get_hostkey_index;
|
|
|
|
return (kex);
|
|
}
|
|
|
|
/* This function requries careful sanity checking */
|
|
|
|
void
|
|
mm_get_keystate(struct monitor *pmonitor)
|
|
{
|
|
Buffer m;
|
|
u_char *blob, *p;
|
|
u_int bloblen, plen;
|
|
u_int32_t seqnr, packets;
|
|
u_int64_t blocks;
|
|
|
|
debug3("%s: Waiting for new keys", __func__);
|
|
|
|
buffer_init(&m);
|
|
mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
|
|
if (!compat20) {
|
|
child_state.ssh1protoflags = buffer_get_int(&m);
|
|
child_state.ssh1cipher = buffer_get_int(&m);
|
|
child_state.ssh1key = buffer_get_string(&m,
|
|
&child_state.ssh1keylen);
|
|
child_state.ivout = buffer_get_string(&m,
|
|
&child_state.ivoutlen);
|
|
child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
|
|
goto skip;
|
|
} else {
|
|
/* Get the Kex for rekeying */
|
|
*pmonitor->m_pkex = mm_get_kex(&m);
|
|
}
|
|
|
|
blob = buffer_get_string(&m, &bloblen);
|
|
current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
|
|
xfree(blob);
|
|
|
|
debug3("%s: Waiting for second key", __func__);
|
|
blob = buffer_get_string(&m, &bloblen);
|
|
current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
|
|
xfree(blob);
|
|
|
|
/* Now get sequence numbers for the packets */
|
|
seqnr = buffer_get_int(&m);
|
|
blocks = buffer_get_int64(&m);
|
|
packets = buffer_get_int(&m);
|
|
packet_set_state(MODE_OUT, seqnr, blocks, packets);
|
|
seqnr = buffer_get_int(&m);
|
|
blocks = buffer_get_int64(&m);
|
|
packets = buffer_get_int(&m);
|
|
packet_set_state(MODE_IN, seqnr, blocks, packets);
|
|
|
|
skip:
|
|
/* Get the key context */
|
|
child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
|
|
child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
|
|
|
|
debug3("%s: Getting compression state", __func__);
|
|
/* Get compression state */
|
|
p = buffer_get_string(&m, &plen);
|
|
if (plen != sizeof(child_state.outgoing))
|
|
fatal("%s: bad request size", __func__);
|
|
memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
|
|
xfree(p);
|
|
|
|
p = buffer_get_string(&m, &plen);
|
|
if (plen != sizeof(child_state.incoming))
|
|
fatal("%s: bad request size", __func__);
|
|
memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
|
|
xfree(p);
|
|
|
|
/* Network I/O buffers */
|
|
debug3("%s: Getting Network I/O buffers", __func__);
|
|
child_state.input = buffer_get_string(&m, &child_state.ilen);
|
|
child_state.output = buffer_get_string(&m, &child_state.olen);
|
|
|
|
buffer_free(&m);
|
|
}
|
|
|
|
|
|
/* Allocation functions for zlib */
|
|
void *
|
|
mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
|
|
{
|
|
size_t len = (size_t) size * ncount;
|
|
void *address;
|
|
|
|
if (len == 0 || ncount > SIZE_T_MAX / size)
|
|
fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
|
|
|
|
address = mm_malloc(mm, len);
|
|
|
|
return (address);
|
|
}
|
|
|
|
void
|
|
mm_zfree(struct mm_master *mm, void *address)
|
|
{
|
|
mm_free(mm, address);
|
|
}
|
|
|
|
void
|
|
mm_init_compression(struct mm_master *mm)
|
|
{
|
|
outgoing_stream.zalloc = (alloc_func)mm_zalloc;
|
|
outgoing_stream.zfree = (free_func)mm_zfree;
|
|
outgoing_stream.opaque = mm;
|
|
|
|
incoming_stream.zalloc = (alloc_func)mm_zalloc;
|
|
incoming_stream.zfree = (free_func)mm_zfree;
|
|
incoming_stream.opaque = mm;
|
|
}
|
|
|
|
/* XXX */
|
|
|
|
#define FD_CLOSEONEXEC(x) do { \
|
|
if (fcntl(x, F_SETFD, 1) == -1) \
|
|
fatal("fcntl(%d, F_SETFD)", x); \
|
|
} while (0)
|
|
|
|
static void
|
|
monitor_socketpair(int *pair)
|
|
{
|
|
#ifdef HAVE_SOCKETPAIR
|
|
if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
|
|
fatal("%s: socketpair", __func__);
|
|
#else
|
|
fatal("%s: UsePrivilegeSeparation=yes not supported",
|
|
__func__);
|
|
#endif
|
|
FD_CLOSEONEXEC(pair[0]);
|
|
FD_CLOSEONEXEC(pair[1]);
|
|
}
|
|
|
|
#define MM_MEMSIZE 65536
|
|
|
|
struct monitor *
|
|
monitor_init(void)
|
|
{
|
|
struct monitor *mon;
|
|
int pair[2];
|
|
|
|
mon = xmalloc(sizeof(*mon));
|
|
|
|
monitor_socketpair(pair);
|
|
|
|
mon->m_recvfd = pair[0];
|
|
mon->m_sendfd = pair[1];
|
|
|
|
/* Used to share zlib space across processes */
|
|
if (options.compression) {
|
|
mon->m_zback = mm_create(NULL, MM_MEMSIZE);
|
|
mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
|
|
|
|
/* Compression needs to share state across borders */
|
|
mm_init_compression(mon->m_zlib);
|
|
}
|
|
|
|
return mon;
|
|
}
|
|
|
|
void
|
|
monitor_reinit(struct monitor *mon)
|
|
{
|
|
int pair[2];
|
|
|
|
monitor_socketpair(pair);
|
|
|
|
mon->m_recvfd = pair[0];
|
|
mon->m_sendfd = pair[1];
|
|
}
|
|
|
|
#ifdef GSSAPI
|
|
int
|
|
mm_answer_gss_setup_ctx(int socket, Buffer *m)
|
|
{
|
|
gss_OID_desc oid;
|
|
OM_uint32 major;
|
|
u_int len;
|
|
|
|
oid.elements = buffer_get_string(m, &len);
|
|
oid.length = len;
|
|
|
|
major = ssh_gssapi_server_ctx(&gsscontext, &oid);
|
|
|
|
xfree(oid.elements);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, major);
|
|
|
|
mm_request_send(socket,MONITOR_ANS_GSSSETUP, m);
|
|
|
|
/* Now we have a context, enable the step */
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_gss_accept_ctx(int socket, Buffer *m)
|
|
{
|
|
gss_buffer_desc in;
|
|
gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
|
|
OM_uint32 major,minor;
|
|
OM_uint32 flags = 0; /* GSI needs this */
|
|
u_int len;
|
|
|
|
in.value = buffer_get_string(m, &len);
|
|
in.length = len;
|
|
major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
|
|
xfree(in.value);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, major);
|
|
buffer_put_string(m, out.value, out.length);
|
|
buffer_put_int(m, flags);
|
|
mm_request_send(socket, MONITOR_ANS_GSSSTEP, m);
|
|
|
|
gss_release_buffer(&minor, &out);
|
|
|
|
/* Complete - now we can do signing */
|
|
if (major==GSS_S_COMPLETE) {
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
|
|
monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
mm_answer_gss_userok(int socket, Buffer *m)
|
|
{
|
|
int authenticated;
|
|
|
|
authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
|
|
|
|
buffer_clear(m);
|
|
buffer_put_int(m, authenticated);
|
|
|
|
debug3("%s: sending result %d", __func__, authenticated);
|
|
mm_request_send(socket, MONITOR_ANS_GSSUSEROK, m);
|
|
|
|
auth_method="gssapi";
|
|
|
|
/* Monitor loop will terminate if authenticated */
|
|
return (authenticated);
|
|
}
|
|
#endif /* GSSAPI */
|