crypto/openssh/auth-bsdauth.c

   1 /* $OpenBSD: auth-bsdauth.c,v 1.14 2015/10/20 23:24:25 mmcc Exp $ */
   2 /*
   3  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "includes.h"
  27
  28 #include <sys/types.h>
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31
  32 #include <stdarg.h>
  33
  34 #ifdef BSD_AUTH
  35 #include "xmalloc.h"
  36 #include "key.h"
  37 #include "hostfile.h"
  38 #include "auth.h"
  39 #include "log.h"
  40 #include "buffer.h"
  41 #ifdef GSSAPI
  42 #include "ssh-gss.h"
  43 #endif
  44 #include "monitor_wrap.h"
  45
  46 static void *
  47 bsdauth_init_ctx(Authctxt *authctxt)
  48 {
  49         return authctxt;
  50 }
  51
  52 int
  53 bsdauth_query(void *ctx, char **name, char **infotxt,
  54    u_int *numprompts, char ***prompts, u_int **echo_on)
  55 {
  56         Authctxt *authctxt = ctx;
  57         char *challenge = NULL;
  58
  59         *infotxt = NULL;
  60         *numprompts = 0;
  61         *prompts = NULL;
  62         *echo_on = NULL;
  63
  64         if (authctxt->as != NULL) {
  65                 debug2("bsdauth_query: try reuse session");
  66                 challenge = auth_getitem(authctxt->as, AUTHV_CHALLENGE);
  67                 if (challenge == NULL) {
  68                         auth_close(authctxt->as);
  69                         authctxt->as = NULL;
  70                 }
  71         }
  72
  73         if (challenge == NULL) {
  74                 debug2("bsdauth_query: new bsd auth session");
  75                 debug3("bsdauth_query: style %s",
  76                     authctxt->style ? authctxt->style : "<default>");
  77                 authctxt->as = auth_userchallenge(authctxt->user,
  78                     authctxt->style, "auth-ssh", &challenge);
  79                 if (authctxt->as == NULL)
  80                         challenge = NULL;
  81                 debug2("bsdauth_query: <%s>", challenge ? challenge : "empty");
  82         }
  83
  84         if (challenge == NULL)
  85                 return -1;
  86
  87         *name = xstrdup("");
  88         *infotxt = xstrdup("");
  89         *numprompts = 1;
  90         *prompts = xcalloc(*numprompts, sizeof(char *));
  91         *echo_on = xcalloc(*numprompts, sizeof(u_int));
  92         (*prompts)[0] = xstrdup(challenge);
  93
  94         return 0;
  95 }
  96
  97 int
  98 bsdauth_respond(void *ctx, u_int numresponses, char **responses)
  99 {
 100         Authctxt *authctxt = ctx;
 101         int authok;
 102
 103         if (!authctxt->valid)
 104                 return -1;
 105
 106         if (authctxt->as == NULL)
 107                 error("bsdauth_respond: no bsd auth session");
 108
 109         if (numresponses != 1)
 110                 return -1;
 111
 112         authok = auth_userresponse(authctxt->as, responses[0], 0);
 113         authctxt->as = NULL;
 114         debug3("bsdauth_respond: <%s> = <%d>", responses[0], authok);
 115
 116         return (authok == 0) ? -1 : 0;
 117 }
 118
 119 static void
 120 bsdauth_free_ctx(void *ctx)
 121 {
 122         Authctxt *authctxt = ctx;
 123
 124         if (authctxt && authctxt->as) {
 125                 auth_close(authctxt->as);
 126                 authctxt->as = NULL;
 127         }
 128 }
 129
 130 KbdintDevice bsdauth_device = {
 131         "bsdauth",
 132         bsdauth_init_ctx,
 133         bsdauth_query,
 134         bsdauth_respond,
 135         bsdauth_free_ctx
 136 };
 137
 138 KbdintDevice mm_bsdauth_device = {
 139         "bsdauth",
 140         bsdauth_init_ctx,
 141         mm_bsdauth_query,
 142         mm_bsdauth_respond,
 143         bsdauth_free_ctx
 144 };
 145 #endif