Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1 | /* $OpenBSD: monitor.c,v 1.145 2015/02/20 22:17:21 djm Exp $ */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2 | /* |
| 3 | * Copyright 2002 Niels Provos <provos@citi.umich.edu> |
| 4 | * Copyright 2002 Markus Friedl <markus@openbsd.org> |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 17 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 18 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 19 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 21 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 22 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 23 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 25 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | |
| 28 | #include "includes.h" |
| 29 | |
| 30 | #include <sys/types.h> |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 31 | #include <sys/socket.h> |
| 32 | #include "openbsd-compat/sys-tree.h" |
| 33 | #include <sys/wait.h> |
| 34 | |
| 35 | #include <errno.h> |
| 36 | #include <fcntl.h> |
| 37 | #ifdef HAVE_PATHS_H |
| 38 | #include <paths.h> |
| 39 | #endif |
| 40 | #include <pwd.h> |
| 41 | #include <signal.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 42 | #ifdef HAVE_STDINT_H |
| 43 | #include <stdint.h> |
| 44 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 45 | #include <stdlib.h> |
| 46 | #include <string.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 47 | #include <stdarg.h> |
| 48 | #include <stdio.h> |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 49 | #include <unistd.h> |
| 50 | #ifdef HAVE_POLL_H |
| 51 | #include <poll.h> |
| 52 | #else |
| 53 | # ifdef HAVE_SYS_POLL_H |
| 54 | # include <sys/poll.h> |
| 55 | # endif |
| 56 | #endif |
| 57 | |
| 58 | #ifdef SKEY |
| 59 | #include <skey.h> |
| 60 | #endif |
| 61 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 62 | #ifdef WITH_OPENSSL |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 63 | #include <openssl/dh.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 64 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 65 | |
| 66 | #include "openbsd-compat/sys-queue.h" |
| 67 | #include "atomicio.h" |
| 68 | #include "xmalloc.h" |
| 69 | #include "ssh.h" |
| 70 | #include "key.h" |
| 71 | #include "buffer.h" |
| 72 | #include "hostfile.h" |
| 73 | #include "auth.h" |
| 74 | #include "cipher.h" |
| 75 | #include "kex.h" |
| 76 | #include "dh.h" |
| 77 | #ifdef TARGET_OS_MAC /* XXX Broken krb5 headers on Mac */ |
| 78 | #undef TARGET_OS_MAC |
| 79 | #include "zlib.h" |
| 80 | #define TARGET_OS_MAC 1 |
| 81 | #else |
| 82 | #include "zlib.h" |
| 83 | #endif |
| 84 | #include "packet.h" |
| 85 | #include "auth-options.h" |
| 86 | #include "sshpty.h" |
| 87 | #include "channels.h" |
| 88 | #include "session.h" |
| 89 | #include "sshlogin.h" |
| 90 | #include "canohost.h" |
| 91 | #include "log.h" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 92 | #include "misc.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 93 | #include "servconf.h" |
| 94 | #include "monitor.h" |
| 95 | #include "monitor_mm.h" |
| 96 | #ifdef GSSAPI |
| 97 | #include "ssh-gss.h" |
| 98 | #endif |
| 99 | #include "monitor_wrap.h" |
| 100 | #include "monitor_fdpass.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 101 | #include "compat.h" |
| 102 | #include "ssh2.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 103 | #include "roaming.h" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 104 | #include "authfd.h" |
| 105 | #include "match.h" |
| 106 | #include "ssherr.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 107 | |
| 108 | #ifdef GSSAPI |
| 109 | static Gssctxt *gsscontext = NULL; |
| 110 | #endif |
| 111 | |
| 112 | /* Imports */ |
| 113 | extern ServerOptions options; |
| 114 | extern u_int utmp_len; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 115 | extern u_char session_id[]; |
| 116 | extern Buffer auth_debug; |
| 117 | extern int auth_debug_init; |
| 118 | extern Buffer loginmsg; |
| 119 | |
| 120 | /* State exported from the child */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 121 | static struct sshbuf *child_state; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 122 | |
| 123 | /* Functions on the monitor that answer unprivileged requests */ |
| 124 | |
| 125 | int mm_answer_moduli(int, Buffer *); |
| 126 | int mm_answer_sign(int, Buffer *); |
| 127 | int mm_answer_pwnamallow(int, Buffer *); |
| 128 | int mm_answer_auth2_read_banner(int, Buffer *); |
| 129 | int mm_answer_authserv(int, Buffer *); |
| 130 | int mm_answer_authpassword(int, Buffer *); |
| 131 | int mm_answer_bsdauthquery(int, Buffer *); |
| 132 | int mm_answer_bsdauthrespond(int, Buffer *); |
| 133 | int mm_answer_skeyquery(int, Buffer *); |
| 134 | int mm_answer_skeyrespond(int, Buffer *); |
| 135 | int mm_answer_keyallowed(int, Buffer *); |
| 136 | int mm_answer_keyverify(int, Buffer *); |
| 137 | int mm_answer_pty(int, Buffer *); |
| 138 | int mm_answer_pty_cleanup(int, Buffer *); |
| 139 | int mm_answer_term(int, Buffer *); |
| 140 | int mm_answer_rsa_keyallowed(int, Buffer *); |
| 141 | int mm_answer_rsa_challenge(int, Buffer *); |
| 142 | int mm_answer_rsa_response(int, Buffer *); |
| 143 | int mm_answer_sesskey(int, Buffer *); |
| 144 | int mm_answer_sessid(int, Buffer *); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 145 | |
| 146 | #ifdef USE_PAM |
| 147 | int mm_answer_pam_start(int, Buffer *); |
| 148 | int mm_answer_pam_account(int, Buffer *); |
| 149 | int mm_answer_pam_init_ctx(int, Buffer *); |
| 150 | int mm_answer_pam_query(int, Buffer *); |
| 151 | int mm_answer_pam_respond(int, Buffer *); |
| 152 | int mm_answer_pam_free_ctx(int, Buffer *); |
| 153 | #endif |
| 154 | |
| 155 | #ifdef GSSAPI |
| 156 | int mm_answer_gss_setup_ctx(int, Buffer *); |
| 157 | int mm_answer_gss_accept_ctx(int, Buffer *); |
| 158 | int mm_answer_gss_userok(int, Buffer *); |
| 159 | int mm_answer_gss_checkmic(int, Buffer *); |
| 160 | #endif |
| 161 | |
| 162 | #ifdef SSH_AUDIT_EVENTS |
| 163 | int mm_answer_audit_event(int, Buffer *); |
| 164 | int mm_answer_audit_command(int, Buffer *); |
| 165 | #endif |
| 166 | |
| 167 | static int monitor_read_log(struct monitor *); |
| 168 | |
| 169 | static Authctxt *authctxt; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 170 | |
| 171 | #ifdef WITH_SSH1 |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 172 | static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 173 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 174 | |
| 175 | /* local state for key verify */ |
| 176 | static u_char *key_blob = NULL; |
| 177 | static u_int key_bloblen = 0; |
| 178 | static int key_blobtype = MM_NOKEY; |
| 179 | static char *hostbased_cuser = NULL; |
| 180 | static char *hostbased_chost = NULL; |
| 181 | static char *auth_method = "unknown"; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 182 | static char *auth_submethod = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 183 | static u_int session_id2_len = 0; |
| 184 | static u_char *session_id2 = NULL; |
| 185 | static pid_t monitor_child_pid; |
| 186 | |
| 187 | struct mon_table { |
| 188 | enum monitor_reqtype type; |
| 189 | int flags; |
| 190 | int (*f)(int, Buffer *); |
| 191 | }; |
| 192 | |
| 193 | #define MON_ISAUTH 0x0004 /* Required for Authentication */ |
| 194 | #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */ |
| 195 | #define MON_ONCE 0x0010 /* Disable after calling */ |
| 196 | #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */ |
| 197 | |
| 198 | #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE) |
| 199 | |
| 200 | #define MON_PERMIT 0x1000 /* Request is permitted */ |
| 201 | |
| 202 | struct mon_table mon_dispatch_proto20[] = { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 203 | #ifdef WITH_OPENSSL |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 204 | {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli}, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 205 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 206 | {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign}, |
| 207 | {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow}, |
| 208 | {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv}, |
| 209 | {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner}, |
| 210 | {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword}, |
| 211 | #ifdef USE_PAM |
| 212 | {MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start}, |
| 213 | {MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account}, |
| 214 | {MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx}, |
| 215 | {MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query}, |
| 216 | {MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond}, |
| 217 | {MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx}, |
| 218 | #endif |
| 219 | #ifdef SSH_AUDIT_EVENTS |
| 220 | {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event}, |
| 221 | #endif |
| 222 | #ifdef BSD_AUTH |
| 223 | {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery}, |
| 224 | {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond}, |
| 225 | #endif |
| 226 | #ifdef SKEY |
| 227 | {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery}, |
| 228 | {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond}, |
| 229 | #endif |
| 230 | {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed}, |
| 231 | {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify}, |
| 232 | #ifdef GSSAPI |
| 233 | {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx}, |
| 234 | {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx}, |
| 235 | {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok}, |
| 236 | {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic}, |
| 237 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 238 | {0, 0, NULL} |
| 239 | }; |
| 240 | |
| 241 | struct mon_table mon_dispatch_postauth20[] = { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 242 | #ifdef WITH_OPENSSL |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 243 | {MONITOR_REQ_MODULI, 0, mm_answer_moduli}, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 244 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 245 | {MONITOR_REQ_SIGN, 0, mm_answer_sign}, |
| 246 | {MONITOR_REQ_PTY, 0, mm_answer_pty}, |
| 247 | {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup}, |
| 248 | {MONITOR_REQ_TERM, 0, mm_answer_term}, |
| 249 | #ifdef SSH_AUDIT_EVENTS |
| 250 | {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event}, |
| 251 | {MONITOR_REQ_AUDIT_COMMAND, MON_PERMIT, mm_answer_audit_command}, |
| 252 | #endif |
| 253 | {0, 0, NULL} |
| 254 | }; |
| 255 | |
| 256 | struct mon_table mon_dispatch_proto15[] = { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 257 | #ifdef WITH_SSH1 |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 258 | {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow}, |
| 259 | {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey}, |
| 260 | {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid}, |
| 261 | {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword}, |
| 262 | {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed}, |
| 263 | {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed}, |
| 264 | {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge}, |
| 265 | {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response}, |
| 266 | #ifdef BSD_AUTH |
| 267 | {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery}, |
| 268 | {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond}, |
| 269 | #endif |
| 270 | #ifdef SKEY |
| 271 | {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery}, |
| 272 | {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond}, |
| 273 | #endif |
| 274 | #ifdef USE_PAM |
| 275 | {MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start}, |
| 276 | {MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account}, |
| 277 | {MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx}, |
| 278 | {MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query}, |
| 279 | {MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond}, |
| 280 | {MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx}, |
| 281 | #endif |
| 282 | #ifdef SSH_AUDIT_EVENTS |
| 283 | {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event}, |
| 284 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 285 | #endif /* WITH_SSH1 */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 286 | {0, 0, NULL} |
| 287 | }; |
| 288 | |
| 289 | struct mon_table mon_dispatch_postauth15[] = { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 290 | #ifdef WITH_SSH1 |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 291 | {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty}, |
| 292 | {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup}, |
| 293 | {MONITOR_REQ_TERM, 0, mm_answer_term}, |
| 294 | #ifdef SSH_AUDIT_EVENTS |
| 295 | {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event}, |
| 296 | {MONITOR_REQ_AUDIT_COMMAND, MON_PERMIT|MON_ONCE, mm_answer_audit_command}, |
| 297 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 298 | #endif /* WITH_SSH1 */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 299 | {0, 0, NULL} |
| 300 | }; |
| 301 | |
| 302 | struct mon_table *mon_dispatch; |
| 303 | |
| 304 | /* Specifies if a certain message is allowed at the moment */ |
| 305 | |
| 306 | static void |
| 307 | monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit) |
| 308 | { |
| 309 | while (ent->f != NULL) { |
| 310 | if (ent->type == type) { |
| 311 | ent->flags &= ~MON_PERMIT; |
| 312 | ent->flags |= permit ? MON_PERMIT : 0; |
| 313 | return; |
| 314 | } |
| 315 | ent++; |
| 316 | } |
| 317 | } |
| 318 | |
| 319 | static void |
| 320 | monitor_permit_authentications(int permit) |
| 321 | { |
| 322 | struct mon_table *ent = mon_dispatch; |
| 323 | |
| 324 | while (ent->f != NULL) { |
| 325 | if (ent->flags & MON_AUTH) { |
| 326 | ent->flags &= ~MON_PERMIT; |
| 327 | ent->flags |= permit ? MON_PERMIT : 0; |
| 328 | } |
| 329 | ent++; |
| 330 | } |
| 331 | } |
| 332 | |
| 333 | void |
| 334 | monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor) |
| 335 | { |
| 336 | struct mon_table *ent; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 337 | int authenticated = 0, partial = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 338 | |
| 339 | debug3("preauth child monitor started"); |
| 340 | |
| 341 | close(pmonitor->m_recvfd); |
| 342 | close(pmonitor->m_log_sendfd); |
| 343 | pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1; |
| 344 | |
| 345 | authctxt = _authctxt; |
| 346 | memset(authctxt, 0, sizeof(*authctxt)); |
| 347 | |
| 348 | authctxt->loginmsg = &loginmsg; |
| 349 | |
| 350 | if (compat20) { |
| 351 | mon_dispatch = mon_dispatch_proto20; |
| 352 | |
| 353 | /* Permit requests for moduli and signatures */ |
| 354 | monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1); |
| 355 | monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1); |
| 356 | } else { |
| 357 | mon_dispatch = mon_dispatch_proto15; |
| 358 | |
| 359 | monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1); |
| 360 | } |
| 361 | |
| 362 | /* The first few requests do not require asynchronous access */ |
| 363 | while (!authenticated) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 364 | partial = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 365 | auth_method = "unknown"; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 366 | auth_submethod = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 367 | authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 368 | |
| 369 | /* Special handling for multiple required authentications */ |
| 370 | if (options.num_auth_methods != 0) { |
| 371 | if (!compat20) |
| 372 | fatal("AuthenticationMethods is not supported" |
| 373 | "with SSH protocol 1"); |
| 374 | if (authenticated && |
| 375 | !auth2_update_methods_lists(authctxt, |
| 376 | auth_method, auth_submethod)) { |
| 377 | debug3("%s: method %s: partial", __func__, |
| 378 | auth_method); |
| 379 | authenticated = 0; |
| 380 | partial = 1; |
| 381 | } |
| 382 | } |
| 383 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 384 | if (authenticated) { |
| 385 | if (!(ent->flags & MON_AUTHDECIDE)) |
| 386 | fatal("%s: unexpected authentication from %d", |
| 387 | __func__, ent->type); |
| 388 | if (authctxt->pw->pw_uid == 0 && |
| 389 | !auth_root_allowed(auth_method)) |
| 390 | authenticated = 0; |
| 391 | #ifdef USE_PAM |
| 392 | /* PAM needs to perform account checks after auth */ |
| 393 | if (options.use_pam && authenticated) { |
| 394 | Buffer m; |
| 395 | |
| 396 | buffer_init(&m); |
| 397 | mm_request_receive_expect(pmonitor->m_sendfd, |
| 398 | MONITOR_REQ_PAM_ACCOUNT, &m); |
| 399 | authenticated = mm_answer_pam_account(pmonitor->m_sendfd, &m); |
| 400 | buffer_free(&m); |
| 401 | } |
| 402 | #endif |
| 403 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 404 | if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 405 | auth_log(authctxt, authenticated, partial, |
| 406 | auth_method, auth_submethod); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 407 | if (!authenticated) |
| 408 | authctxt->failures++; |
| 409 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 410 | } |
| 411 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 412 | if (!authctxt->valid) |
| 413 | fatal("%s: authenticated invalid user", __func__); |
| 414 | if (strcmp(auth_method, "unknown") == 0) |
| 415 | fatal("%s: authentication method name unknown", __func__); |
| 416 | |
| 417 | debug("%s: %s has been authenticated by privileged process", |
| 418 | __func__, authctxt->user); |
| 419 | |
| 420 | mm_get_keystate(pmonitor); |
| 421 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 422 | /* Drain any buffered messages from the child */ |
| 423 | while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0) |
| 424 | ; |
| 425 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 426 | close(pmonitor->m_sendfd); |
| 427 | close(pmonitor->m_log_recvfd); |
| 428 | pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1; |
| 429 | } |
| 430 | |
| 431 | static void |
| 432 | monitor_set_child_handler(pid_t pid) |
| 433 | { |
| 434 | monitor_child_pid = pid; |
| 435 | } |
| 436 | |
| 437 | static void |
| 438 | monitor_child_handler(int sig) |
| 439 | { |
| 440 | kill(monitor_child_pid, sig); |
| 441 | } |
| 442 | |
| 443 | void |
| 444 | monitor_child_postauth(struct monitor *pmonitor) |
| 445 | { |
| 446 | close(pmonitor->m_recvfd); |
| 447 | pmonitor->m_recvfd = -1; |
| 448 | |
| 449 | monitor_set_child_handler(pmonitor->m_pid); |
| 450 | signal(SIGHUP, &monitor_child_handler); |
| 451 | signal(SIGTERM, &monitor_child_handler); |
| 452 | signal(SIGINT, &monitor_child_handler); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 453 | #ifdef SIGXFSZ |
| 454 | signal(SIGXFSZ, SIG_IGN); |
| 455 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 456 | |
| 457 | if (compat20) { |
| 458 | mon_dispatch = mon_dispatch_postauth20; |
| 459 | |
| 460 | /* Permit requests for moduli and signatures */ |
| 461 | monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1); |
| 462 | monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1); |
| 463 | monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1); |
| 464 | } else { |
| 465 | mon_dispatch = mon_dispatch_postauth15; |
| 466 | monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1); |
| 467 | } |
| 468 | if (!no_pty_flag) { |
| 469 | monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1); |
| 470 | monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1); |
| 471 | } |
| 472 | |
| 473 | for (;;) |
| 474 | monitor_read(pmonitor, mon_dispatch, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 475 | } |
| 476 | |
| 477 | void |
| 478 | monitor_sync(struct monitor *pmonitor) |
| 479 | { |
| 480 | if (options.compression) { |
| 481 | /* The member allocation is not visible, so sync it */ |
| 482 | mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback); |
| 483 | } |
| 484 | } |
| 485 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 486 | /* Allocation functions for zlib */ |
| 487 | static void * |
| 488 | mm_zalloc(struct mm_master *mm, u_int ncount, u_int size) |
| 489 | { |
| 490 | size_t len = (size_t) size * ncount; |
| 491 | void *address; |
| 492 | |
| 493 | if (len == 0 || ncount > SIZE_MAX / size) |
| 494 | fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size); |
| 495 | |
| 496 | address = mm_malloc(mm, len); |
| 497 | |
| 498 | return (address); |
| 499 | } |
| 500 | |
| 501 | static void |
| 502 | mm_zfree(struct mm_master *mm, void *address) |
| 503 | { |
| 504 | mm_free(mm, address); |
| 505 | } |
| 506 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 507 | static int |
| 508 | monitor_read_log(struct monitor *pmonitor) |
| 509 | { |
| 510 | Buffer logmsg; |
| 511 | u_int len, level; |
| 512 | char *msg; |
| 513 | |
| 514 | buffer_init(&logmsg); |
| 515 | |
| 516 | /* Read length */ |
| 517 | buffer_append_space(&logmsg, 4); |
| 518 | if (atomicio(read, pmonitor->m_log_recvfd, |
| 519 | buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg)) { |
| 520 | if (errno == EPIPE) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 521 | buffer_free(&logmsg); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 522 | debug("%s: child log fd closed", __func__); |
| 523 | close(pmonitor->m_log_recvfd); |
| 524 | pmonitor->m_log_recvfd = -1; |
| 525 | return -1; |
| 526 | } |
| 527 | fatal("%s: log fd read: %s", __func__, strerror(errno)); |
| 528 | } |
| 529 | len = buffer_get_int(&logmsg); |
| 530 | if (len <= 4 || len > 8192) |
| 531 | fatal("%s: invalid log message length %u", __func__, len); |
| 532 | |
| 533 | /* Read severity, message */ |
| 534 | buffer_clear(&logmsg); |
| 535 | buffer_append_space(&logmsg, len); |
| 536 | if (atomicio(read, pmonitor->m_log_recvfd, |
| 537 | buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg)) |
| 538 | fatal("%s: log fd read: %s", __func__, strerror(errno)); |
| 539 | |
| 540 | /* Log it */ |
| 541 | level = buffer_get_int(&logmsg); |
| 542 | msg = buffer_get_string(&logmsg, NULL); |
| 543 | if (log_level_name(level) == NULL) |
| 544 | fatal("%s: invalid log level %u (corrupted message?)", |
| 545 | __func__, level); |
| 546 | do_log2(level, "%s [preauth]", msg); |
| 547 | |
| 548 | buffer_free(&logmsg); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 549 | free(msg); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 550 | |
| 551 | return 0; |
| 552 | } |
| 553 | |
| 554 | int |
| 555 | monitor_read(struct monitor *pmonitor, struct mon_table *ent, |
| 556 | struct mon_table **pent) |
| 557 | { |
| 558 | Buffer m; |
| 559 | int ret; |
| 560 | u_char type; |
| 561 | struct pollfd pfd[2]; |
| 562 | |
| 563 | for (;;) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 564 | memset(&pfd, 0, sizeof(pfd)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 565 | pfd[0].fd = pmonitor->m_sendfd; |
| 566 | pfd[0].events = POLLIN; |
| 567 | pfd[1].fd = pmonitor->m_log_recvfd; |
| 568 | pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN; |
| 569 | if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) { |
| 570 | if (errno == EINTR || errno == EAGAIN) |
| 571 | continue; |
| 572 | fatal("%s: poll: %s", __func__, strerror(errno)); |
| 573 | } |
| 574 | if (pfd[1].revents) { |
| 575 | /* |
| 576 | * Drain all log messages before processing next |
| 577 | * monitor request. |
| 578 | */ |
| 579 | monitor_read_log(pmonitor); |
| 580 | continue; |
| 581 | } |
| 582 | if (pfd[0].revents) |
| 583 | break; /* Continues below */ |
| 584 | } |
| 585 | |
| 586 | buffer_init(&m); |
| 587 | |
| 588 | mm_request_receive(pmonitor->m_sendfd, &m); |
| 589 | type = buffer_get_char(&m); |
| 590 | |
| 591 | debug3("%s: checking request %d", __func__, type); |
| 592 | |
| 593 | while (ent->f != NULL) { |
| 594 | if (ent->type == type) |
| 595 | break; |
| 596 | ent++; |
| 597 | } |
| 598 | |
| 599 | if (ent->f != NULL) { |
| 600 | if (!(ent->flags & MON_PERMIT)) |
| 601 | fatal("%s: unpermitted request %d", __func__, |
| 602 | type); |
| 603 | ret = (*ent->f)(pmonitor->m_sendfd, &m); |
| 604 | buffer_free(&m); |
| 605 | |
| 606 | /* The child may use this request only once, disable it */ |
| 607 | if (ent->flags & MON_ONCE) { |
| 608 | debug2("%s: %d used once, disabling now", __func__, |
| 609 | type); |
| 610 | ent->flags &= ~MON_PERMIT; |
| 611 | } |
| 612 | |
| 613 | if (pent != NULL) |
| 614 | *pent = ent; |
| 615 | |
| 616 | return ret; |
| 617 | } |
| 618 | |
| 619 | fatal("%s: unsupported request: %d", __func__, type); |
| 620 | |
| 621 | /* NOTREACHED */ |
| 622 | return (-1); |
| 623 | } |
| 624 | |
| 625 | /* allowed key state */ |
| 626 | static int |
| 627 | monitor_allowed_key(u_char *blob, u_int bloblen) |
| 628 | { |
| 629 | /* make sure key is allowed */ |
| 630 | if (key_blob == NULL || key_bloblen != bloblen || |
| 631 | timingsafe_bcmp(key_blob, blob, key_bloblen)) |
| 632 | return (0); |
| 633 | return (1); |
| 634 | } |
| 635 | |
| 636 | static void |
| 637 | monitor_reset_key_state(void) |
| 638 | { |
| 639 | /* reset state */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 640 | free(key_blob); |
| 641 | free(hostbased_cuser); |
| 642 | free(hostbased_chost); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 643 | key_blob = NULL; |
| 644 | key_bloblen = 0; |
| 645 | key_blobtype = MM_NOKEY; |
| 646 | hostbased_cuser = NULL; |
| 647 | hostbased_chost = NULL; |
| 648 | } |
| 649 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 650 | #ifdef WITH_OPENSSL |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 651 | int |
| 652 | mm_answer_moduli(int sock, Buffer *m) |
| 653 | { |
| 654 | DH *dh; |
| 655 | int min, want, max; |
| 656 | |
| 657 | min = buffer_get_int(m); |
| 658 | want = buffer_get_int(m); |
| 659 | max = buffer_get_int(m); |
| 660 | |
| 661 | debug3("%s: got parameters: %d %d %d", |
| 662 | __func__, min, want, max); |
| 663 | /* We need to check here, too, in case the child got corrupted */ |
| 664 | if (max < min || want < min || max < want) |
| 665 | fatal("%s: bad parameters: %d %d %d", |
| 666 | __func__, min, want, max); |
| 667 | |
| 668 | buffer_clear(m); |
| 669 | |
| 670 | dh = choose_dh(min, want, max); |
| 671 | if (dh == NULL) { |
| 672 | buffer_put_char(m, 0); |
| 673 | return (0); |
| 674 | } else { |
| 675 | /* Send first bignum */ |
| 676 | buffer_put_char(m, 1); |
| 677 | buffer_put_bignum2(m, dh->p); |
| 678 | buffer_put_bignum2(m, dh->g); |
| 679 | |
| 680 | DH_free(dh); |
| 681 | } |
| 682 | mm_request_send(sock, MONITOR_ANS_MODULI, m); |
| 683 | return (0); |
| 684 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 685 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 686 | |
| 687 | int |
| 688 | mm_answer_sign(int sock, Buffer *m) |
| 689 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 690 | struct ssh *ssh = active_state; /* XXX */ |
| 691 | extern int auth_sock; /* XXX move to state struct? */ |
| 692 | struct sshkey *key; |
| 693 | struct sshbuf *sigbuf; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 694 | u_char *p; |
| 695 | u_char *signature; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 696 | size_t datlen, siglen; |
| 697 | int r, keyid, is_proof = 0; |
| 698 | const char proof_req[] = "hostkeys-prove-00@openssh.com"; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 699 | |
| 700 | debug3("%s", __func__); |
| 701 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 702 | if ((r = sshbuf_get_u32(m, &keyid)) != 0 || |
| 703 | (r = sshbuf_get_string(m, &p, &datlen)) != 0) |
| 704 | fatal("%s: buffer error: %s", __func__, ssh_err(r)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 705 | |
| 706 | /* |
| 707 | * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes), |
| 708 | * SHA384 (48 bytes) and SHA512 (64 bytes). |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 709 | * |
| 710 | * Otherwise, verify the signature request is for a hostkey |
| 711 | * proof. |
| 712 | * |
| 713 | * XXX perform similar check for KEX signature requests too? |
| 714 | * it's not trivial, since what is signed is the hash, rather |
| 715 | * than the full kex structure... |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 716 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 717 | if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64) { |
| 718 | /* |
| 719 | * Construct expected hostkey proof and compare it to what |
| 720 | * the client sent us. |
| 721 | */ |
| 722 | if (session_id2_len == 0) /* hostkeys is never first */ |
| 723 | fatal("%s: bad data length: %zu", __func__, datlen); |
| 724 | if ((key = get_hostkey_public_by_index(keyid, ssh)) == NULL) |
| 725 | fatal("%s: no hostkey for index %d", __func__, keyid); |
| 726 | if ((sigbuf = sshbuf_new()) == NULL) |
| 727 | fatal("%s: sshbuf_new", __func__); |
| 728 | if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 || |
| 729 | (r = sshbuf_put_string(sigbuf, session_id2, |
| 730 | session_id2_len) != 0) || |
| 731 | (r = sshkey_puts(key, sigbuf)) != 0) |
| 732 | fatal("%s: couldn't prepare private key " |
| 733 | "proof buffer: %s", __func__, ssh_err(r)); |
| 734 | if (datlen != sshbuf_len(sigbuf) || |
| 735 | memcmp(p, sshbuf_ptr(sigbuf), sshbuf_len(sigbuf)) != 0) |
| 736 | fatal("%s: bad data length: %zu, hostkey proof len %zu", |
| 737 | __func__, datlen, sshbuf_len(sigbuf)); |
| 738 | sshbuf_free(sigbuf); |
| 739 | is_proof = 1; |
| 740 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 741 | |
| 742 | /* save session id, it will be passed on the first call */ |
| 743 | if (session_id2_len == 0) { |
| 744 | session_id2_len = datlen; |
| 745 | session_id2 = xmalloc(session_id2_len); |
| 746 | memcpy(session_id2, p, session_id2_len); |
| 747 | } |
| 748 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 749 | if ((key = get_hostkey_by_index(keyid)) != NULL) { |
| 750 | if ((r = sshkey_sign(key, &signature, &siglen, p, datlen, |
| 751 | datafellows)) != 0) |
| 752 | fatal("%s: sshkey_sign failed: %s", |
| 753 | __func__, ssh_err(r)); |
| 754 | } else if ((key = get_hostkey_public_by_index(keyid, ssh)) != NULL && |
| 755 | auth_sock > 0) { |
| 756 | if ((r = ssh_agent_sign(auth_sock, key, &signature, &siglen, |
| 757 | p, datlen, datafellows)) != 0) { |
| 758 | fatal("%s: ssh_agent_sign failed: %s", |
| 759 | __func__, ssh_err(r)); |
| 760 | } |
| 761 | } else |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 762 | fatal("%s: no hostkey from index %d", __func__, keyid); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 763 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 764 | debug3("%s: %s signature %p(%zu)", __func__, |
| 765 | is_proof ? "KEX" : "hostkey proof", signature, siglen); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 766 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 767 | sshbuf_reset(m); |
| 768 | if ((r = sshbuf_put_string(m, signature, siglen)) != 0) |
| 769 | fatal("%s: buffer error: %s", __func__, ssh_err(r)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 770 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 771 | free(p); |
| 772 | free(signature); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 773 | |
| 774 | mm_request_send(sock, MONITOR_ANS_SIGN, m); |
| 775 | |
| 776 | /* Turn on permissions for getpwnam */ |
| 777 | monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1); |
| 778 | |
| 779 | return (0); |
| 780 | } |
| 781 | |
| 782 | /* Retrieves the password entry and also checks if the user is permitted */ |
| 783 | |
| 784 | int |
| 785 | mm_answer_pwnamallow(int sock, Buffer *m) |
| 786 | { |
| 787 | char *username; |
| 788 | struct passwd *pwent; |
| 789 | int allowed = 0; |
| 790 | u_int i; |
| 791 | |
| 792 | debug3("%s", __func__); |
| 793 | |
| 794 | if (authctxt->attempt++ != 0) |
| 795 | fatal("%s: multiple attempts for getpwnam", __func__); |
| 796 | |
| 797 | username = buffer_get_string(m, NULL); |
| 798 | |
| 799 | pwent = getpwnamallow(username); |
| 800 | |
| 801 | authctxt->user = xstrdup(username); |
| 802 | setproctitle("%s [priv]", pwent ? username : "unknown"); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 803 | free(username); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 804 | |
| 805 | buffer_clear(m); |
| 806 | |
| 807 | if (pwent == NULL) { |
| 808 | buffer_put_char(m, 0); |
| 809 | authctxt->pw = fakepw(); |
| 810 | goto out; |
| 811 | } |
| 812 | |
| 813 | allowed = 1; |
| 814 | authctxt->pw = pwent; |
| 815 | authctxt->valid = 1; |
| 816 | |
| 817 | buffer_put_char(m, 1); |
| 818 | buffer_put_string(m, pwent, sizeof(struct passwd)); |
| 819 | buffer_put_cstring(m, pwent->pw_name); |
| 820 | buffer_put_cstring(m, "*"); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 821 | #ifdef HAVE_STRUCT_PASSWD_PW_GECOS |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 822 | buffer_put_cstring(m, pwent->pw_gecos); |
| 823 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 824 | #ifdef HAVE_STRUCT_PASSWD_PW_CLASS |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 825 | buffer_put_cstring(m, pwent->pw_class); |
| 826 | #endif |
| 827 | buffer_put_cstring(m, pwent->pw_dir); |
| 828 | buffer_put_cstring(m, pwent->pw_shell); |
| 829 | |
| 830 | out: |
| 831 | buffer_put_string(m, &options, sizeof(options)); |
| 832 | |
| 833 | #define M_CP_STROPT(x) do { \ |
| 834 | if (options.x != NULL) \ |
| 835 | buffer_put_cstring(m, options.x); \ |
| 836 | } while (0) |
| 837 | #define M_CP_STRARRAYOPT(x, nx) do { \ |
| 838 | for (i = 0; i < options.nx; i++) \ |
| 839 | buffer_put_cstring(m, options.x[i]); \ |
| 840 | } while (0) |
| 841 | /* See comment in servconf.h */ |
| 842 | COPY_MATCH_STRING_OPTS(); |
| 843 | #undef M_CP_STROPT |
| 844 | #undef M_CP_STRARRAYOPT |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 845 | |
| 846 | /* Create valid auth method lists */ |
| 847 | if (compat20 && auth2_setup_methods_lists(authctxt) != 0) { |
| 848 | /* |
| 849 | * The monitor will continue long enough to let the child |
| 850 | * run to it's packet_disconnect(), but it must not allow any |
| 851 | * authentication to succeed. |
| 852 | */ |
| 853 | debug("%s: no valid authentication method lists", __func__); |
| 854 | } |
| 855 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 856 | debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed); |
| 857 | mm_request_send(sock, MONITOR_ANS_PWNAM, m); |
| 858 | |
| 859 | /* For SSHv1 allow authentication now */ |
| 860 | if (!compat20) |
| 861 | monitor_permit_authentications(1); |
| 862 | else { |
| 863 | /* Allow service/style information on the auth context */ |
| 864 | monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1); |
| 865 | monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1); |
| 866 | } |
| 867 | #ifdef USE_PAM |
| 868 | if (options.use_pam) |
| 869 | monitor_permit(mon_dispatch, MONITOR_REQ_PAM_START, 1); |
| 870 | #endif |
| 871 | |
| 872 | return (0); |
| 873 | } |
| 874 | |
| 875 | int mm_answer_auth2_read_banner(int sock, Buffer *m) |
| 876 | { |
| 877 | char *banner; |
| 878 | |
| 879 | buffer_clear(m); |
| 880 | banner = auth2_read_banner(); |
| 881 | buffer_put_cstring(m, banner != NULL ? banner : ""); |
| 882 | mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 883 | free(banner); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 884 | |
| 885 | return (0); |
| 886 | } |
| 887 | |
| 888 | int |
| 889 | mm_answer_authserv(int sock, Buffer *m) |
| 890 | { |
| 891 | monitor_permit_authentications(1); |
| 892 | |
| 893 | authctxt->service = buffer_get_string(m, NULL); |
| 894 | authctxt->style = buffer_get_string(m, NULL); |
| 895 | debug3("%s: service=%s, style=%s", |
| 896 | __func__, authctxt->service, authctxt->style); |
| 897 | |
| 898 | if (strlen(authctxt->style) == 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 899 | free(authctxt->style); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 900 | authctxt->style = NULL; |
| 901 | } |
| 902 | |
| 903 | return (0); |
| 904 | } |
| 905 | |
| 906 | int |
| 907 | mm_answer_authpassword(int sock, Buffer *m) |
| 908 | { |
| 909 | static int call_count; |
| 910 | char *passwd; |
| 911 | int authenticated; |
| 912 | u_int plen; |
| 913 | |
| 914 | passwd = buffer_get_string(m, &plen); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 915 | #if !defined(ANDROID) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 916 | /* Only authenticate if the context is valid */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 917 | authenticated = options.password_authentication && |
| 918 | auth_password(authctxt, passwd); |
| 919 | #else |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 920 | /* no password authentication in Android. */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 921 | authenticated = 0; |
| 922 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 923 | explicit_bzero(passwd, strlen(passwd)); |
| 924 | free(passwd); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 925 | |
| 926 | buffer_clear(m); |
| 927 | buffer_put_int(m, authenticated); |
| 928 | |
| 929 | debug3("%s: sending result %d", __func__, authenticated); |
| 930 | mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m); |
| 931 | |
| 932 | call_count++; |
| 933 | if (plen == 0 && call_count == 1) |
| 934 | auth_method = "none"; |
| 935 | else |
| 936 | auth_method = "password"; |
| 937 | |
| 938 | /* Causes monitor loop to terminate if authenticated */ |
| 939 | return (authenticated); |
| 940 | } |
| 941 | |
| 942 | #ifdef BSD_AUTH |
| 943 | int |
| 944 | mm_answer_bsdauthquery(int sock, Buffer *m) |
| 945 | { |
| 946 | char *name, *infotxt; |
| 947 | u_int numprompts; |
| 948 | u_int *echo_on; |
| 949 | char **prompts; |
| 950 | u_int success; |
| 951 | |
| 952 | success = bsdauth_query(authctxt, &name, &infotxt, &numprompts, |
| 953 | &prompts, &echo_on) < 0 ? 0 : 1; |
| 954 | |
| 955 | buffer_clear(m); |
| 956 | buffer_put_int(m, success); |
| 957 | if (success) |
| 958 | buffer_put_cstring(m, prompts[0]); |
| 959 | |
| 960 | debug3("%s: sending challenge success: %u", __func__, success); |
| 961 | mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m); |
| 962 | |
| 963 | if (success) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 964 | free(name); |
| 965 | free(infotxt); |
| 966 | free(prompts); |
| 967 | free(echo_on); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 968 | } |
| 969 | |
| 970 | return (0); |
| 971 | } |
| 972 | |
| 973 | int |
| 974 | mm_answer_bsdauthrespond(int sock, Buffer *m) |
| 975 | { |
| 976 | char *response; |
| 977 | int authok; |
| 978 | |
| 979 | if (authctxt->as == 0) |
| 980 | fatal("%s: no bsd auth session", __func__); |
| 981 | |
| 982 | response = buffer_get_string(m, NULL); |
| 983 | authok = options.challenge_response_authentication && |
| 984 | auth_userresponse(authctxt->as, response, 0); |
| 985 | authctxt->as = NULL; |
| 986 | debug3("%s: <%s> = <%d>", __func__, response, authok); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 987 | free(response); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 988 | |
| 989 | buffer_clear(m); |
| 990 | buffer_put_int(m, authok); |
| 991 | |
| 992 | debug3("%s: sending authenticated: %d", __func__, authok); |
| 993 | mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m); |
| 994 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 995 | if (compat20) { |
| 996 | auth_method = "keyboard-interactive"; |
| 997 | auth_submethod = "bsdauth"; |
| 998 | } else |
| 999 | auth_method = "bsdauth"; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1000 | |
| 1001 | return (authok != 0); |
| 1002 | } |
| 1003 | #endif |
| 1004 | |
| 1005 | #ifdef SKEY |
| 1006 | int |
| 1007 | mm_answer_skeyquery(int sock, Buffer *m) |
| 1008 | { |
| 1009 | struct skey skey; |
| 1010 | char challenge[1024]; |
| 1011 | u_int success; |
| 1012 | |
| 1013 | success = _compat_skeychallenge(&skey, authctxt->user, challenge, |
| 1014 | sizeof(challenge)) < 0 ? 0 : 1; |
| 1015 | |
| 1016 | buffer_clear(m); |
| 1017 | buffer_put_int(m, success); |
| 1018 | if (success) |
| 1019 | buffer_put_cstring(m, challenge); |
| 1020 | |
| 1021 | debug3("%s: sending challenge success: %u", __func__, success); |
| 1022 | mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m); |
| 1023 | |
| 1024 | return (0); |
| 1025 | } |
| 1026 | |
| 1027 | int |
| 1028 | mm_answer_skeyrespond(int sock, Buffer *m) |
| 1029 | { |
| 1030 | char *response; |
| 1031 | int authok; |
| 1032 | |
| 1033 | response = buffer_get_string(m, NULL); |
| 1034 | |
| 1035 | authok = (options.challenge_response_authentication && |
| 1036 | authctxt->valid && |
| 1037 | skey_haskey(authctxt->pw->pw_name) == 0 && |
| 1038 | skey_passcheck(authctxt->pw->pw_name, response) != -1); |
| 1039 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1040 | free(response); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1041 | |
| 1042 | buffer_clear(m); |
| 1043 | buffer_put_int(m, authok); |
| 1044 | |
| 1045 | debug3("%s: sending authenticated: %d", __func__, authok); |
| 1046 | mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m); |
| 1047 | |
| 1048 | auth_method = "skey"; |
| 1049 | |
| 1050 | return (authok != 0); |
| 1051 | } |
| 1052 | #endif |
| 1053 | |
| 1054 | #ifdef USE_PAM |
| 1055 | int |
| 1056 | mm_answer_pam_start(int sock, Buffer *m) |
| 1057 | { |
| 1058 | if (!options.use_pam) |
| 1059 | fatal("UsePAM not set, but ended up in %s anyway", __func__); |
| 1060 | |
| 1061 | start_pam(authctxt); |
| 1062 | |
| 1063 | monitor_permit(mon_dispatch, MONITOR_REQ_PAM_ACCOUNT, 1); |
| 1064 | |
| 1065 | return (0); |
| 1066 | } |
| 1067 | |
| 1068 | int |
| 1069 | mm_answer_pam_account(int sock, Buffer *m) |
| 1070 | { |
| 1071 | u_int ret; |
| 1072 | |
| 1073 | if (!options.use_pam) |
| 1074 | fatal("UsePAM not set, but ended up in %s anyway", __func__); |
| 1075 | |
| 1076 | ret = do_pam_account(); |
| 1077 | |
| 1078 | buffer_put_int(m, ret); |
| 1079 | buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg)); |
| 1080 | |
| 1081 | mm_request_send(sock, MONITOR_ANS_PAM_ACCOUNT, m); |
| 1082 | |
| 1083 | return (ret); |
| 1084 | } |
| 1085 | |
| 1086 | static void *sshpam_ctxt, *sshpam_authok; |
| 1087 | extern KbdintDevice sshpam_device; |
| 1088 | |
| 1089 | int |
| 1090 | mm_answer_pam_init_ctx(int sock, Buffer *m) |
| 1091 | { |
| 1092 | |
| 1093 | debug3("%s", __func__); |
| 1094 | authctxt->user = buffer_get_string(m, NULL); |
| 1095 | sshpam_ctxt = (sshpam_device.init_ctx)(authctxt); |
| 1096 | sshpam_authok = NULL; |
| 1097 | buffer_clear(m); |
| 1098 | if (sshpam_ctxt != NULL) { |
| 1099 | monitor_permit(mon_dispatch, MONITOR_REQ_PAM_FREE_CTX, 1); |
| 1100 | buffer_put_int(m, 1); |
| 1101 | } else { |
| 1102 | buffer_put_int(m, 0); |
| 1103 | } |
| 1104 | mm_request_send(sock, MONITOR_ANS_PAM_INIT_CTX, m); |
| 1105 | return (0); |
| 1106 | } |
| 1107 | |
| 1108 | int |
| 1109 | mm_answer_pam_query(int sock, Buffer *m) |
| 1110 | { |
| 1111 | char *name = NULL, *info = NULL, **prompts = NULL; |
| 1112 | u_int i, num = 0, *echo_on = 0; |
| 1113 | int ret; |
| 1114 | |
| 1115 | debug3("%s", __func__); |
| 1116 | sshpam_authok = NULL; |
| 1117 | ret = (sshpam_device.query)(sshpam_ctxt, &name, &info, &num, &prompts, &echo_on); |
| 1118 | if (ret == 0 && num == 0) |
| 1119 | sshpam_authok = sshpam_ctxt; |
| 1120 | if (num > 1 || name == NULL || info == NULL) |
| 1121 | ret = -1; |
| 1122 | buffer_clear(m); |
| 1123 | buffer_put_int(m, ret); |
| 1124 | buffer_put_cstring(m, name); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1125 | free(name); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1126 | buffer_put_cstring(m, info); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1127 | free(info); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1128 | buffer_put_int(m, num); |
| 1129 | for (i = 0; i < num; ++i) { |
| 1130 | buffer_put_cstring(m, prompts[i]); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1131 | free(prompts[i]); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1132 | buffer_put_int(m, echo_on[i]); |
| 1133 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1134 | free(prompts); |
| 1135 | free(echo_on); |
| 1136 | auth_method = "keyboard-interactive"; |
| 1137 | auth_submethod = "pam"; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1138 | mm_request_send(sock, MONITOR_ANS_PAM_QUERY, m); |
| 1139 | return (0); |
| 1140 | } |
| 1141 | |
| 1142 | int |
| 1143 | mm_answer_pam_respond(int sock, Buffer *m) |
| 1144 | { |
| 1145 | char **resp; |
| 1146 | u_int i, num; |
| 1147 | int ret; |
| 1148 | |
| 1149 | debug3("%s", __func__); |
| 1150 | sshpam_authok = NULL; |
| 1151 | num = buffer_get_int(m); |
| 1152 | if (num > 0) { |
| 1153 | resp = xcalloc(num, sizeof(char *)); |
| 1154 | for (i = 0; i < num; ++i) |
| 1155 | resp[i] = buffer_get_string(m, NULL); |
| 1156 | ret = (sshpam_device.respond)(sshpam_ctxt, num, resp); |
| 1157 | for (i = 0; i < num; ++i) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1158 | free(resp[i]); |
| 1159 | free(resp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1160 | } else { |
| 1161 | ret = (sshpam_device.respond)(sshpam_ctxt, num, NULL); |
| 1162 | } |
| 1163 | buffer_clear(m); |
| 1164 | buffer_put_int(m, ret); |
| 1165 | mm_request_send(sock, MONITOR_ANS_PAM_RESPOND, m); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1166 | auth_method = "keyboard-interactive"; |
| 1167 | auth_submethod = "pam"; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1168 | if (ret == 0) |
| 1169 | sshpam_authok = sshpam_ctxt; |
| 1170 | return (0); |
| 1171 | } |
| 1172 | |
| 1173 | int |
| 1174 | mm_answer_pam_free_ctx(int sock, Buffer *m) |
| 1175 | { |
| 1176 | |
| 1177 | debug3("%s", __func__); |
| 1178 | (sshpam_device.free_ctx)(sshpam_ctxt); |
| 1179 | buffer_clear(m); |
| 1180 | mm_request_send(sock, MONITOR_ANS_PAM_FREE_CTX, m); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1181 | auth_method = "keyboard-interactive"; |
| 1182 | auth_submethod = "pam"; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1183 | return (sshpam_authok == sshpam_ctxt); |
| 1184 | } |
| 1185 | #endif |
| 1186 | |
| 1187 | int |
| 1188 | mm_answer_keyallowed(int sock, Buffer *m) |
| 1189 | { |
| 1190 | Key *key; |
| 1191 | char *cuser, *chost; |
| 1192 | u_char *blob; |
| 1193 | u_int bloblen; |
| 1194 | enum mm_keytype type = 0; |
| 1195 | int allowed = 0; |
| 1196 | |
| 1197 | debug3("%s entering", __func__); |
| 1198 | |
| 1199 | type = buffer_get_int(m); |
| 1200 | cuser = buffer_get_string(m, NULL); |
| 1201 | chost = buffer_get_string(m, NULL); |
| 1202 | blob = buffer_get_string(m, &bloblen); |
| 1203 | |
| 1204 | key = key_from_blob(blob, bloblen); |
| 1205 | |
| 1206 | if ((compat20 && type == MM_RSAHOSTKEY) || |
| 1207 | (!compat20 && type != MM_RSAHOSTKEY)) |
| 1208 | fatal("%s: key type and protocol mismatch", __func__); |
| 1209 | |
| 1210 | debug3("%s: key_from_blob: %p", __func__, key); |
| 1211 | |
| 1212 | if (key != NULL && authctxt->valid) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1213 | /* These should not make it past the privsep child */ |
| 1214 | if (key_type_plain(key->type) == KEY_RSA && |
| 1215 | (datafellows & SSH_BUG_RSASIGMD5) != 0) |
| 1216 | fatal("%s: passed a SSH_BUG_RSASIGMD5 key", __func__); |
| 1217 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1218 | switch (type) { |
| 1219 | case MM_USERKEY: |
| 1220 | allowed = options.pubkey_authentication && |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1221 | !auth2_userkey_already_used(authctxt, key) && |
| 1222 | match_pattern_list(sshkey_ssh_name(key), |
| 1223 | options.pubkey_key_types, |
| 1224 | strlen(options.pubkey_key_types), 0) == 1 && |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1225 | user_key_allowed(authctxt->pw, key); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1226 | pubkey_auth_info(authctxt, key, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1227 | auth_method = "publickey"; |
| 1228 | if (options.pubkey_authentication && allowed != 1) |
| 1229 | auth_clear_options(); |
| 1230 | break; |
| 1231 | case MM_HOSTKEY: |
| 1232 | allowed = options.hostbased_authentication && |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1233 | match_pattern_list(sshkey_ssh_name(key), |
| 1234 | options.hostbased_key_types, |
| 1235 | strlen(options.hostbased_key_types), 0) == 1 && |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1236 | hostbased_key_allowed(authctxt->pw, |
| 1237 | cuser, chost, key); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1238 | pubkey_auth_info(authctxt, key, |
| 1239 | "client user \"%.100s\", client host \"%.100s\"", |
| 1240 | cuser, chost); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1241 | auth_method = "hostbased"; |
| 1242 | break; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1243 | #ifdef WITH_SSH1 |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1244 | case MM_RSAHOSTKEY: |
| 1245 | key->type = KEY_RSA1; /* XXX */ |
| 1246 | allowed = options.rhosts_rsa_authentication && |
| 1247 | auth_rhosts_rsa_key_allowed(authctxt->pw, |
| 1248 | cuser, chost, key); |
| 1249 | if (options.rhosts_rsa_authentication && allowed != 1) |
| 1250 | auth_clear_options(); |
| 1251 | auth_method = "rsa"; |
| 1252 | break; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1253 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1254 | default: |
| 1255 | fatal("%s: unknown key type %d", __func__, type); |
| 1256 | break; |
| 1257 | } |
| 1258 | } |
| 1259 | if (key != NULL) |
| 1260 | key_free(key); |
| 1261 | |
| 1262 | /* clear temporarily storage (used by verify) */ |
| 1263 | monitor_reset_key_state(); |
| 1264 | |
| 1265 | if (allowed) { |
| 1266 | /* Save temporarily for comparison in verify */ |
| 1267 | key_blob = blob; |
| 1268 | key_bloblen = bloblen; |
| 1269 | key_blobtype = type; |
| 1270 | hostbased_cuser = cuser; |
| 1271 | hostbased_chost = chost; |
| 1272 | } else { |
| 1273 | /* Log failed attempt */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1274 | auth_log(authctxt, 0, 0, auth_method, NULL); |
| 1275 | free(blob); |
| 1276 | free(cuser); |
| 1277 | free(chost); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1278 | } |
| 1279 | |
| 1280 | debug3("%s: key %p is %s", |
| 1281 | __func__, key, allowed ? "allowed" : "not allowed"); |
| 1282 | |
| 1283 | buffer_clear(m); |
| 1284 | buffer_put_int(m, allowed); |
| 1285 | buffer_put_int(m, forced_command != NULL); |
| 1286 | |
| 1287 | mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m); |
| 1288 | |
| 1289 | if (type == MM_RSAHOSTKEY) |
| 1290 | monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed); |
| 1291 | |
| 1292 | return (0); |
| 1293 | } |
| 1294 | |
| 1295 | static int |
| 1296 | monitor_valid_userblob(u_char *data, u_int datalen) |
| 1297 | { |
| 1298 | Buffer b; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1299 | char *p, *userstyle; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1300 | u_int len; |
| 1301 | int fail = 0; |
| 1302 | |
| 1303 | buffer_init(&b); |
| 1304 | buffer_append(&b, data, datalen); |
| 1305 | |
| 1306 | if (datafellows & SSH_OLD_SESSIONID) { |
| 1307 | p = buffer_ptr(&b); |
| 1308 | len = buffer_len(&b); |
| 1309 | if ((session_id2 == NULL) || |
| 1310 | (len < session_id2_len) || |
| 1311 | (timingsafe_bcmp(p, session_id2, session_id2_len) != 0)) |
| 1312 | fail++; |
| 1313 | buffer_consume(&b, session_id2_len); |
| 1314 | } else { |
| 1315 | p = buffer_get_string(&b, &len); |
| 1316 | if ((session_id2 == NULL) || |
| 1317 | (len != session_id2_len) || |
| 1318 | (timingsafe_bcmp(p, session_id2, session_id2_len) != 0)) |
| 1319 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1320 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1321 | } |
| 1322 | if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST) |
| 1323 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1324 | p = buffer_get_cstring(&b, NULL); |
| 1325 | xasprintf(&userstyle, "%s%s%s", authctxt->user, |
| 1326 | authctxt->style ? ":" : "", |
| 1327 | authctxt->style ? authctxt->style : ""); |
| 1328 | if (strcmp(userstyle, p) != 0) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1329 | logit("wrong user name passed to monitor: expected %s != %.100s", |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1330 | userstyle, p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1331 | fail++; |
| 1332 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1333 | free(userstyle); |
| 1334 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1335 | buffer_skip_string(&b); |
| 1336 | if (datafellows & SSH_BUG_PKAUTH) { |
| 1337 | if (!buffer_get_char(&b)) |
| 1338 | fail++; |
| 1339 | } else { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1340 | p = buffer_get_cstring(&b, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1341 | if (strcmp("publickey", p) != 0) |
| 1342 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1343 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1344 | if (!buffer_get_char(&b)) |
| 1345 | fail++; |
| 1346 | buffer_skip_string(&b); |
| 1347 | } |
| 1348 | buffer_skip_string(&b); |
| 1349 | if (buffer_len(&b) != 0) |
| 1350 | fail++; |
| 1351 | buffer_free(&b); |
| 1352 | return (fail == 0); |
| 1353 | } |
| 1354 | |
| 1355 | static int |
| 1356 | monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser, |
| 1357 | char *chost) |
| 1358 | { |
| 1359 | Buffer b; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1360 | char *p, *userstyle; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1361 | u_int len; |
| 1362 | int fail = 0; |
| 1363 | |
| 1364 | buffer_init(&b); |
| 1365 | buffer_append(&b, data, datalen); |
| 1366 | |
| 1367 | p = buffer_get_string(&b, &len); |
| 1368 | if ((session_id2 == NULL) || |
| 1369 | (len != session_id2_len) || |
| 1370 | (timingsafe_bcmp(p, session_id2, session_id2_len) != 0)) |
| 1371 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1372 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1373 | |
| 1374 | if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST) |
| 1375 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1376 | p = buffer_get_cstring(&b, NULL); |
| 1377 | xasprintf(&userstyle, "%s%s%s", authctxt->user, |
| 1378 | authctxt->style ? ":" : "", |
| 1379 | authctxt->style ? authctxt->style : ""); |
| 1380 | if (strcmp(userstyle, p) != 0) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1381 | logit("wrong user name passed to monitor: expected %s != %.100s", |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1382 | userstyle, p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1383 | fail++; |
| 1384 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1385 | free(userstyle); |
| 1386 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1387 | buffer_skip_string(&b); /* service */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1388 | p = buffer_get_cstring(&b, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1389 | if (strcmp(p, "hostbased") != 0) |
| 1390 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1391 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1392 | buffer_skip_string(&b); /* pkalg */ |
| 1393 | buffer_skip_string(&b); /* pkblob */ |
| 1394 | |
| 1395 | /* verify client host, strip trailing dot if necessary */ |
| 1396 | p = buffer_get_string(&b, NULL); |
| 1397 | if (((len = strlen(p)) > 0) && p[len - 1] == '.') |
| 1398 | p[len - 1] = '\0'; |
| 1399 | if (strcmp(p, chost) != 0) |
| 1400 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1401 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1402 | |
| 1403 | /* verify client user */ |
| 1404 | p = buffer_get_string(&b, NULL); |
| 1405 | if (strcmp(p, cuser) != 0) |
| 1406 | fail++; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1407 | free(p); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1408 | |
| 1409 | if (buffer_len(&b) != 0) |
| 1410 | fail++; |
| 1411 | buffer_free(&b); |
| 1412 | return (fail == 0); |
| 1413 | } |
| 1414 | |
| 1415 | int |
| 1416 | mm_answer_keyverify(int sock, Buffer *m) |
| 1417 | { |
| 1418 | Key *key; |
| 1419 | u_char *signature, *data, *blob; |
| 1420 | u_int signaturelen, datalen, bloblen; |
| 1421 | int verified = 0; |
| 1422 | int valid_data = 0; |
| 1423 | |
| 1424 | blob = buffer_get_string(m, &bloblen); |
| 1425 | signature = buffer_get_string(m, &signaturelen); |
| 1426 | data = buffer_get_string(m, &datalen); |
| 1427 | |
| 1428 | if (hostbased_cuser == NULL || hostbased_chost == NULL || |
| 1429 | !monitor_allowed_key(blob, bloblen)) |
| 1430 | fatal("%s: bad key, not previously allowed", __func__); |
| 1431 | |
| 1432 | key = key_from_blob(blob, bloblen); |
| 1433 | if (key == NULL) |
| 1434 | fatal("%s: bad public key blob", __func__); |
| 1435 | |
| 1436 | switch (key_blobtype) { |
| 1437 | case MM_USERKEY: |
| 1438 | valid_data = monitor_valid_userblob(data, datalen); |
| 1439 | break; |
| 1440 | case MM_HOSTKEY: |
| 1441 | valid_data = monitor_valid_hostbasedblob(data, datalen, |
| 1442 | hostbased_cuser, hostbased_chost); |
| 1443 | break; |
| 1444 | default: |
| 1445 | valid_data = 0; |
| 1446 | break; |
| 1447 | } |
| 1448 | if (!valid_data) |
| 1449 | fatal("%s: bad signature data blob", __func__); |
| 1450 | |
| 1451 | verified = key_verify(key, signature, signaturelen, data, datalen); |
| 1452 | debug3("%s: key %p signature %s", |
| 1453 | __func__, key, (verified == 1) ? "verified" : "unverified"); |
| 1454 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1455 | /* If auth was successful then record key to ensure it isn't reused */ |
| 1456 | if (verified == 1) |
| 1457 | auth2_record_userkey(authctxt, key); |
| 1458 | else |
| 1459 | key_free(key); |
| 1460 | |
| 1461 | free(blob); |
| 1462 | free(signature); |
| 1463 | free(data); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1464 | |
| 1465 | auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased"; |
| 1466 | |
| 1467 | monitor_reset_key_state(); |
| 1468 | |
| 1469 | buffer_clear(m); |
| 1470 | buffer_put_int(m, verified); |
| 1471 | mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m); |
| 1472 | |
| 1473 | return (verified == 1); |
| 1474 | } |
| 1475 | |
| 1476 | static void |
| 1477 | mm_record_login(Session *s, struct passwd *pw) |
| 1478 | { |
| 1479 | socklen_t fromlen; |
| 1480 | struct sockaddr_storage from; |
| 1481 | |
| 1482 | /* |
| 1483 | * Get IP address of client. If the connection is not a socket, let |
| 1484 | * the address be 0.0.0.0. |
| 1485 | */ |
| 1486 | memset(&from, 0, sizeof(from)); |
| 1487 | fromlen = sizeof(from); |
| 1488 | if (packet_connection_is_on_socket()) { |
| 1489 | if (getpeername(packet_get_connection_in(), |
| 1490 | (struct sockaddr *)&from, &fromlen) < 0) { |
| 1491 | debug("getpeername: %.100s", strerror(errno)); |
| 1492 | cleanup_exit(255); |
| 1493 | } |
| 1494 | } |
| 1495 | /* Record that there was a login on that tty from the remote host. */ |
| 1496 | record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid, |
| 1497 | get_remote_name_or_ip(utmp_len, options.use_dns), |
| 1498 | (struct sockaddr *)&from, fromlen); |
| 1499 | } |
| 1500 | |
| 1501 | static void |
| 1502 | mm_session_close(Session *s) |
| 1503 | { |
| 1504 | debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid); |
| 1505 | if (s->ttyfd != -1) { |
| 1506 | debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd); |
| 1507 | session_pty_cleanup2(s); |
| 1508 | } |
| 1509 | session_unused(s->self); |
| 1510 | } |
| 1511 | |
| 1512 | int |
| 1513 | mm_answer_pty(int sock, Buffer *m) |
| 1514 | { |
| 1515 | extern struct monitor *pmonitor; |
| 1516 | Session *s; |
| 1517 | int res, fd0; |
| 1518 | |
| 1519 | debug3("%s entering", __func__); |
| 1520 | |
| 1521 | buffer_clear(m); |
| 1522 | s = session_new(); |
| 1523 | if (s == NULL) |
| 1524 | goto error; |
| 1525 | s->authctxt = authctxt; |
| 1526 | s->pw = authctxt->pw; |
| 1527 | s->pid = pmonitor->m_pid; |
| 1528 | res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty)); |
| 1529 | if (res == 0) |
| 1530 | goto error; |
| 1531 | pty_setowner(authctxt->pw, s->tty); |
| 1532 | |
| 1533 | buffer_put_int(m, 1); |
| 1534 | buffer_put_cstring(m, s->tty); |
| 1535 | |
| 1536 | /* We need to trick ttyslot */ |
| 1537 | if (dup2(s->ttyfd, 0) == -1) |
| 1538 | fatal("%s: dup2", __func__); |
| 1539 | |
| 1540 | mm_record_login(s, authctxt->pw); |
| 1541 | |
| 1542 | /* Now we can close the file descriptor again */ |
| 1543 | close(0); |
| 1544 | |
| 1545 | /* send messages generated by record_login */ |
| 1546 | buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg)); |
| 1547 | buffer_clear(&loginmsg); |
| 1548 | |
| 1549 | mm_request_send(sock, MONITOR_ANS_PTY, m); |
| 1550 | |
| 1551 | if (mm_send_fd(sock, s->ptyfd) == -1 || |
| 1552 | mm_send_fd(sock, s->ttyfd) == -1) |
| 1553 | fatal("%s: send fds failed", __func__); |
| 1554 | |
| 1555 | /* make sure nothing uses fd 0 */ |
| 1556 | if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0) |
| 1557 | fatal("%s: open(/dev/null): %s", __func__, strerror(errno)); |
| 1558 | if (fd0 != 0) |
| 1559 | error("%s: fd0 %d != 0", __func__, fd0); |
| 1560 | |
| 1561 | /* slave is not needed */ |
| 1562 | close(s->ttyfd); |
| 1563 | s->ttyfd = s->ptyfd; |
| 1564 | /* no need to dup() because nobody closes ptyfd */ |
| 1565 | s->ptymaster = s->ptyfd; |
| 1566 | |
| 1567 | debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd); |
| 1568 | |
| 1569 | return (0); |
| 1570 | |
| 1571 | error: |
| 1572 | if (s != NULL) |
| 1573 | mm_session_close(s); |
| 1574 | buffer_put_int(m, 0); |
| 1575 | mm_request_send(sock, MONITOR_ANS_PTY, m); |
| 1576 | return (0); |
| 1577 | } |
| 1578 | |
| 1579 | int |
| 1580 | mm_answer_pty_cleanup(int sock, Buffer *m) |
| 1581 | { |
| 1582 | Session *s; |
| 1583 | char *tty; |
| 1584 | |
| 1585 | debug3("%s entering", __func__); |
| 1586 | |
| 1587 | tty = buffer_get_string(m, NULL); |
| 1588 | if ((s = session_by_tty(tty)) != NULL) |
| 1589 | mm_session_close(s); |
| 1590 | buffer_clear(m); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1591 | free(tty); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1592 | return (0); |
| 1593 | } |
| 1594 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1595 | #ifdef WITH_SSH1 |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1596 | int |
| 1597 | mm_answer_sesskey(int sock, Buffer *m) |
| 1598 | { |
| 1599 | BIGNUM *p; |
| 1600 | int rsafail; |
| 1601 | |
| 1602 | /* Turn off permissions */ |
| 1603 | monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0); |
| 1604 | |
| 1605 | if ((p = BN_new()) == NULL) |
| 1606 | fatal("%s: BN_new", __func__); |
| 1607 | |
| 1608 | buffer_get_bignum2(m, p); |
| 1609 | |
| 1610 | rsafail = ssh1_session_key(p); |
| 1611 | |
| 1612 | buffer_clear(m); |
| 1613 | buffer_put_int(m, rsafail); |
| 1614 | buffer_put_bignum2(m, p); |
| 1615 | |
| 1616 | BN_clear_free(p); |
| 1617 | |
| 1618 | mm_request_send(sock, MONITOR_ANS_SESSKEY, m); |
| 1619 | |
| 1620 | /* Turn on permissions for sessid passing */ |
| 1621 | monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1); |
| 1622 | |
| 1623 | return (0); |
| 1624 | } |
| 1625 | |
| 1626 | int |
| 1627 | mm_answer_sessid(int sock, Buffer *m) |
| 1628 | { |
| 1629 | int i; |
| 1630 | |
| 1631 | debug3("%s entering", __func__); |
| 1632 | |
| 1633 | if (buffer_len(m) != 16) |
| 1634 | fatal("%s: bad ssh1 session id", __func__); |
| 1635 | for (i = 0; i < 16; i++) |
| 1636 | session_id[i] = buffer_get_char(m); |
| 1637 | |
| 1638 | /* Turn on permissions for getpwnam */ |
| 1639 | monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1); |
| 1640 | |
| 1641 | return (0); |
| 1642 | } |
| 1643 | |
| 1644 | int |
| 1645 | mm_answer_rsa_keyallowed(int sock, Buffer *m) |
| 1646 | { |
| 1647 | BIGNUM *client_n; |
| 1648 | Key *key = NULL; |
| 1649 | u_char *blob = NULL; |
| 1650 | u_int blen = 0; |
| 1651 | int allowed = 0; |
| 1652 | |
| 1653 | debug3("%s entering", __func__); |
| 1654 | |
| 1655 | auth_method = "rsa"; |
| 1656 | if (options.rsa_authentication && authctxt->valid) { |
| 1657 | if ((client_n = BN_new()) == NULL) |
| 1658 | fatal("%s: BN_new", __func__); |
| 1659 | buffer_get_bignum2(m, client_n); |
| 1660 | allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key); |
| 1661 | BN_clear_free(client_n); |
| 1662 | } |
| 1663 | buffer_clear(m); |
| 1664 | buffer_put_int(m, allowed); |
| 1665 | buffer_put_int(m, forced_command != NULL); |
| 1666 | |
| 1667 | /* clear temporarily storage (used by generate challenge) */ |
| 1668 | monitor_reset_key_state(); |
| 1669 | |
| 1670 | if (allowed && key != NULL) { |
| 1671 | key->type = KEY_RSA; /* cheat for key_to_blob */ |
| 1672 | if (key_to_blob(key, &blob, &blen) == 0) |
| 1673 | fatal("%s: key_to_blob failed", __func__); |
| 1674 | buffer_put_string(m, blob, blen); |
| 1675 | |
| 1676 | /* Save temporarily for comparison in verify */ |
| 1677 | key_blob = blob; |
| 1678 | key_bloblen = blen; |
| 1679 | key_blobtype = MM_RSAUSERKEY; |
| 1680 | } |
| 1681 | if (key != NULL) |
| 1682 | key_free(key); |
| 1683 | |
| 1684 | mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m); |
| 1685 | |
| 1686 | monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed); |
| 1687 | monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0); |
| 1688 | return (0); |
| 1689 | } |
| 1690 | |
| 1691 | int |
| 1692 | mm_answer_rsa_challenge(int sock, Buffer *m) |
| 1693 | { |
| 1694 | Key *key = NULL; |
| 1695 | u_char *blob; |
| 1696 | u_int blen; |
| 1697 | |
| 1698 | debug3("%s entering", __func__); |
| 1699 | |
| 1700 | if (!authctxt->valid) |
| 1701 | fatal("%s: authctxt not valid", __func__); |
| 1702 | blob = buffer_get_string(m, &blen); |
| 1703 | if (!monitor_allowed_key(blob, blen)) |
| 1704 | fatal("%s: bad key, not previously allowed", __func__); |
| 1705 | if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY) |
| 1706 | fatal("%s: key type mismatch", __func__); |
| 1707 | if ((key = key_from_blob(blob, blen)) == NULL) |
| 1708 | fatal("%s: received bad key", __func__); |
| 1709 | if (key->type != KEY_RSA) |
| 1710 | fatal("%s: received bad key type %d", __func__, key->type); |
| 1711 | key->type = KEY_RSA1; |
| 1712 | if (ssh1_challenge) |
| 1713 | BN_clear_free(ssh1_challenge); |
| 1714 | ssh1_challenge = auth_rsa_generate_challenge(key); |
| 1715 | |
| 1716 | buffer_clear(m); |
| 1717 | buffer_put_bignum2(m, ssh1_challenge); |
| 1718 | |
| 1719 | debug3("%s sending reply", __func__); |
| 1720 | mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m); |
| 1721 | |
| 1722 | monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1); |
| 1723 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1724 | free(blob); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1725 | key_free(key); |
| 1726 | return (0); |
| 1727 | } |
| 1728 | |
| 1729 | int |
| 1730 | mm_answer_rsa_response(int sock, Buffer *m) |
| 1731 | { |
| 1732 | Key *key = NULL; |
| 1733 | u_char *blob, *response; |
| 1734 | u_int blen, len; |
| 1735 | int success; |
| 1736 | |
| 1737 | debug3("%s entering", __func__); |
| 1738 | |
| 1739 | if (!authctxt->valid) |
| 1740 | fatal("%s: authctxt not valid", __func__); |
| 1741 | if (ssh1_challenge == NULL) |
| 1742 | fatal("%s: no ssh1_challenge", __func__); |
| 1743 | |
| 1744 | blob = buffer_get_string(m, &blen); |
| 1745 | if (!monitor_allowed_key(blob, blen)) |
| 1746 | fatal("%s: bad key, not previously allowed", __func__); |
| 1747 | if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY) |
| 1748 | fatal("%s: key type mismatch: %d", __func__, key_blobtype); |
| 1749 | if ((key = key_from_blob(blob, blen)) == NULL) |
| 1750 | fatal("%s: received bad key", __func__); |
| 1751 | response = buffer_get_string(m, &len); |
| 1752 | if (len != 16) |
| 1753 | fatal("%s: received bad response to challenge", __func__); |
| 1754 | success = auth_rsa_verify_response(key, ssh1_challenge, response); |
| 1755 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1756 | free(blob); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1757 | key_free(key); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1758 | free(response); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1759 | |
| 1760 | auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa"; |
| 1761 | |
| 1762 | /* reset state */ |
| 1763 | BN_clear_free(ssh1_challenge); |
| 1764 | ssh1_challenge = NULL; |
| 1765 | monitor_reset_key_state(); |
| 1766 | |
| 1767 | buffer_clear(m); |
| 1768 | buffer_put_int(m, success); |
| 1769 | mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m); |
| 1770 | |
| 1771 | return (success); |
| 1772 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1773 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1774 | |
| 1775 | int |
| 1776 | mm_answer_term(int sock, Buffer *req) |
| 1777 | { |
| 1778 | extern struct monitor *pmonitor; |
| 1779 | int res, status; |
| 1780 | |
| 1781 | debug3("%s: tearing down sessions", __func__); |
| 1782 | |
| 1783 | /* The child is terminating */ |
| 1784 | session_destroy_all(&mm_session_close); |
| 1785 | |
| 1786 | #ifdef USE_PAM |
| 1787 | if (options.use_pam) |
| 1788 | sshpam_cleanup(); |
| 1789 | #endif |
| 1790 | |
| 1791 | while (waitpid(pmonitor->m_pid, &status, 0) == -1) |
| 1792 | if (errno != EINTR) |
| 1793 | exit(1); |
| 1794 | |
| 1795 | res = WIFEXITED(status) ? WEXITSTATUS(status) : 1; |
| 1796 | |
| 1797 | /* Terminate process */ |
| 1798 | exit(res); |
| 1799 | } |
| 1800 | |
| 1801 | #ifdef SSH_AUDIT_EVENTS |
| 1802 | /* Report that an audit event occurred */ |
| 1803 | int |
| 1804 | mm_answer_audit_event(int socket, Buffer *m) |
| 1805 | { |
| 1806 | ssh_audit_event_t event; |
| 1807 | |
| 1808 | debug3("%s entering", __func__); |
| 1809 | |
| 1810 | event = buffer_get_int(m); |
| 1811 | switch(event) { |
| 1812 | case SSH_AUTH_FAIL_PUBKEY: |
| 1813 | case SSH_AUTH_FAIL_HOSTBASED: |
| 1814 | case SSH_AUTH_FAIL_GSSAPI: |
| 1815 | case SSH_LOGIN_EXCEED_MAXTRIES: |
| 1816 | case SSH_LOGIN_ROOT_DENIED: |
| 1817 | case SSH_CONNECTION_CLOSE: |
| 1818 | case SSH_INVALID_USER: |
| 1819 | audit_event(event); |
| 1820 | break; |
| 1821 | default: |
| 1822 | fatal("Audit event type %d not permitted", event); |
| 1823 | } |
| 1824 | |
| 1825 | return (0); |
| 1826 | } |
| 1827 | |
| 1828 | int |
| 1829 | mm_answer_audit_command(int socket, Buffer *m) |
| 1830 | { |
| 1831 | u_int len; |
| 1832 | char *cmd; |
| 1833 | |
| 1834 | debug3("%s entering", __func__); |
| 1835 | cmd = buffer_get_string(m, &len); |
| 1836 | /* sanity check command, if so how? */ |
| 1837 | audit_run_command(cmd); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1838 | free(cmd); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1839 | return (0); |
| 1840 | } |
| 1841 | #endif /* SSH_AUDIT_EVENTS */ |
| 1842 | |
| 1843 | void |
| 1844 | monitor_apply_keystate(struct monitor *pmonitor) |
| 1845 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1846 | struct ssh *ssh = active_state; /* XXX */ |
| 1847 | struct kex *kex; |
| 1848 | int r; |
| 1849 | |
| 1850 | debug3("%s: packet_set_state", __func__); |
| 1851 | if ((r = ssh_packet_set_state(ssh, child_state)) != 0) |
| 1852 | fatal("%s: packet_set_state: %s", __func__, ssh_err(r)); |
| 1853 | sshbuf_free(child_state); |
| 1854 | child_state = NULL; |
| 1855 | |
| 1856 | if ((kex = ssh->kex) != 0) { |
| 1857 | /* XXX set callbacks */ |
| 1858 | #ifdef WITH_OPENSSL |
| 1859 | kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server; |
| 1860 | kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server; |
| 1861 | kex->kex[KEX_DH_GEX_SHA1] = kexgex_server; |
| 1862 | kex->kex[KEX_DH_GEX_SHA256] = kexgex_server; |
| 1863 | # ifdef OPENSSL_HAS_ECC |
| 1864 | kex->kex[KEX_ECDH_SHA2] = kexecdh_server; |
| 1865 | # endif |
| 1866 | #endif /* WITH_OPENSSL */ |
| 1867 | kex->kex[KEX_C25519_SHA256] = kexc25519_server; |
| 1868 | kex->load_host_public_key=&get_hostkey_public_by_type; |
| 1869 | kex->load_host_private_key=&get_hostkey_private_by_type; |
| 1870 | kex->host_key_index=&get_hostkey_index; |
| 1871 | kex->sign = sshd_hostkey_sign; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1872 | } |
| 1873 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1874 | /* Update with new address */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1875 | if (options.compression) { |
| 1876 | ssh_packet_set_compress_hooks(ssh, pmonitor->m_zlib, |
| 1877 | (ssh_packet_comp_alloc_func *)mm_zalloc, |
| 1878 | (ssh_packet_comp_free_func *)mm_zfree); |
| 1879 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1880 | } |
| 1881 | |
| 1882 | /* This function requries careful sanity checking */ |
| 1883 | |
| 1884 | void |
| 1885 | mm_get_keystate(struct monitor *pmonitor) |
| 1886 | { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1887 | debug3("%s: Waiting for new keys", __func__); |
| 1888 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1889 | if ((child_state = sshbuf_new()) == NULL) |
| 1890 | fatal("%s: sshbuf_new failed", __func__); |
| 1891 | mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, |
| 1892 | child_state); |
| 1893 | debug3("%s: GOT new keys", __func__); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1894 | } |
| 1895 | |
| 1896 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1897 | /* XXX */ |
| 1898 | |
| 1899 | #define FD_CLOSEONEXEC(x) do { \ |
| 1900 | if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \ |
| 1901 | fatal("fcntl(%d, F_SETFD)", x); \ |
| 1902 | } while (0) |
| 1903 | |
| 1904 | static void |
| 1905 | monitor_openfds(struct monitor *mon, int do_logfds) |
| 1906 | { |
| 1907 | int pair[2]; |
| 1908 | |
| 1909 | if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1) |
| 1910 | fatal("%s: socketpair: %s", __func__, strerror(errno)); |
| 1911 | FD_CLOSEONEXEC(pair[0]); |
| 1912 | FD_CLOSEONEXEC(pair[1]); |
| 1913 | mon->m_recvfd = pair[0]; |
| 1914 | mon->m_sendfd = pair[1]; |
| 1915 | |
| 1916 | if (do_logfds) { |
| 1917 | if (pipe(pair) == -1) |
| 1918 | fatal("%s: pipe: %s", __func__, strerror(errno)); |
| 1919 | FD_CLOSEONEXEC(pair[0]); |
| 1920 | FD_CLOSEONEXEC(pair[1]); |
| 1921 | mon->m_log_recvfd = pair[0]; |
| 1922 | mon->m_log_sendfd = pair[1]; |
| 1923 | } else |
| 1924 | mon->m_log_recvfd = mon->m_log_sendfd = -1; |
| 1925 | } |
| 1926 | |
| 1927 | #define MM_MEMSIZE 65536 |
| 1928 | |
| 1929 | struct monitor * |
| 1930 | monitor_init(void) |
| 1931 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1932 | struct ssh *ssh = active_state; /* XXX */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1933 | struct monitor *mon; |
| 1934 | |
| 1935 | mon = xcalloc(1, sizeof(*mon)); |
| 1936 | |
| 1937 | monitor_openfds(mon, 1); |
| 1938 | |
| 1939 | /* Used to share zlib space across processes */ |
| 1940 | if (options.compression) { |
| 1941 | mon->m_zback = mm_create(NULL, MM_MEMSIZE); |
| 1942 | mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE); |
| 1943 | |
| 1944 | /* Compression needs to share state across borders */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1945 | ssh_packet_set_compress_hooks(ssh, mon->m_zlib, |
| 1946 | (ssh_packet_comp_alloc_func *)mm_zalloc, |
| 1947 | (ssh_packet_comp_free_func *)mm_zfree); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1948 | } |
| 1949 | |
| 1950 | return mon; |
| 1951 | } |
| 1952 | |
| 1953 | void |
| 1954 | monitor_reinit(struct monitor *mon) |
| 1955 | { |
| 1956 | monitor_openfds(mon, 0); |
| 1957 | } |
| 1958 | |
| 1959 | #ifdef GSSAPI |
| 1960 | int |
| 1961 | mm_answer_gss_setup_ctx(int sock, Buffer *m) |
| 1962 | { |
| 1963 | gss_OID_desc goid; |
| 1964 | OM_uint32 major; |
| 1965 | u_int len; |
| 1966 | |
| 1967 | goid.elements = buffer_get_string(m, &len); |
| 1968 | goid.length = len; |
| 1969 | |
| 1970 | major = ssh_gssapi_server_ctx(&gsscontext, &goid); |
| 1971 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1972 | free(goid.elements); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1973 | |
| 1974 | buffer_clear(m); |
| 1975 | buffer_put_int(m, major); |
| 1976 | |
| 1977 | mm_request_send(sock, MONITOR_ANS_GSSSETUP, m); |
| 1978 | |
| 1979 | /* Now we have a context, enable the step */ |
| 1980 | monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1); |
| 1981 | |
| 1982 | return (0); |
| 1983 | } |
| 1984 | |
| 1985 | int |
| 1986 | mm_answer_gss_accept_ctx(int sock, Buffer *m) |
| 1987 | { |
| 1988 | gss_buffer_desc in; |
| 1989 | gss_buffer_desc out = GSS_C_EMPTY_BUFFER; |
| 1990 | OM_uint32 major, minor; |
| 1991 | OM_uint32 flags = 0; /* GSI needs this */ |
| 1992 | u_int len; |
| 1993 | |
| 1994 | in.value = buffer_get_string(m, &len); |
| 1995 | in.length = len; |
| 1996 | major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1997 | free(in.value); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1998 | |
| 1999 | buffer_clear(m); |
| 2000 | buffer_put_int(m, major); |
| 2001 | buffer_put_string(m, out.value, out.length); |
| 2002 | buffer_put_int(m, flags); |
| 2003 | mm_request_send(sock, MONITOR_ANS_GSSSTEP, m); |
| 2004 | |
| 2005 | gss_release_buffer(&minor, &out); |
| 2006 | |
| 2007 | if (major == GSS_S_COMPLETE) { |
| 2008 | monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0); |
| 2009 | monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1); |
| 2010 | monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1); |
| 2011 | } |
| 2012 | return (0); |
| 2013 | } |
| 2014 | |
| 2015 | int |
| 2016 | mm_answer_gss_checkmic(int sock, Buffer *m) |
| 2017 | { |
| 2018 | gss_buffer_desc gssbuf, mic; |
| 2019 | OM_uint32 ret; |
| 2020 | u_int len; |
| 2021 | |
| 2022 | gssbuf.value = buffer_get_string(m, &len); |
| 2023 | gssbuf.length = len; |
| 2024 | mic.value = buffer_get_string(m, &len); |
| 2025 | mic.length = len; |
| 2026 | |
| 2027 | ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic); |
| 2028 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 2029 | free(gssbuf.value); |
| 2030 | free(mic.value); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2031 | |
| 2032 | buffer_clear(m); |
| 2033 | buffer_put_int(m, ret); |
| 2034 | |
| 2035 | mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m); |
| 2036 | |
| 2037 | if (!GSS_ERROR(ret)) |
| 2038 | monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1); |
| 2039 | |
| 2040 | return (0); |
| 2041 | } |
| 2042 | |
| 2043 | int |
| 2044 | mm_answer_gss_userok(int sock, Buffer *m) |
| 2045 | { |
| 2046 | int authenticated; |
| 2047 | |
| 2048 | authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user); |
| 2049 | |
| 2050 | buffer_clear(m); |
| 2051 | buffer_put_int(m, authenticated); |
| 2052 | |
| 2053 | debug3("%s: sending result %d", __func__, authenticated); |
| 2054 | mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m); |
| 2055 | |
| 2056 | auth_method = "gssapi-with-mic"; |
| 2057 | |
| 2058 | /* Monitor loop will terminate if authenticated */ |
| 2059 | return (authenticated); |
| 2060 | } |
| 2061 | #endif /* GSSAPI */ |
| 2062 | |