xref: /openssh-portable/auth-bsdauth.c (revision c7d39ac8)
1 /* $OpenBSD: auth-bsdauth.c,v 1.15 2018/07/09 21:35:50 markus 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 "sshkey.h"
37 #include "sshbuf.h"
38 #include "hostfile.h"
39 #include "auth.h"
40 #include "log.h"
41 #ifdef GSSAPI
42 #include "ssh-gss.h"
43 #endif
44 #include "monitor_wrap.h"
45 
46 static void *
bsdauth_init_ctx(Authctxt * authctxt)47 bsdauth_init_ctx(Authctxt *authctxt)
48 {
49 	return authctxt;
50 }
51 
52 int
bsdauth_query(void * ctx,char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)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
bsdauth_respond(void * ctx,u_int numresponses,char ** responses)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
bsdauth_free_ctx(void * ctx)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
146