xref: /freebsd/crypto/openssh/auth-bsdauth.c (revision 61e21613)
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 #ifdef BSD_AUTH
33 #include "xmalloc.h"
34 #include "sshkey.h"
35 #include "sshbuf.h"
36 #include "hostfile.h"
37 #include "auth.h"
38 #include "log.h"
39 #ifdef GSSAPI
40 #include "ssh-gss.h"
41 #endif
42 #include "monitor_wrap.h"
43 
44 static void *
45 bsdauth_init_ctx(Authctxt *authctxt)
46 {
47 	return authctxt;
48 }
49 
50 int
51 bsdauth_query(void *ctx, char **name, char **infotxt,
52    u_int *numprompts, char ***prompts, u_int **echo_on)
53 {
54 	Authctxt *authctxt = ctx;
55 	char *challenge = NULL;
56 
57 	*infotxt = NULL;
58 	*numprompts = 0;
59 	*prompts = NULL;
60 	*echo_on = NULL;
61 
62 	if (authctxt->as != NULL) {
63 		debug2("bsdauth_query: try reuse session");
64 		challenge = auth_getitem(authctxt->as, AUTHV_CHALLENGE);
65 		if (challenge == NULL) {
66 			auth_close(authctxt->as);
67 			authctxt->as = NULL;
68 		}
69 	}
70 
71 	if (challenge == NULL) {
72 		debug2("bsdauth_query: new bsd auth session");
73 		debug3("bsdauth_query: style %s",
74 		    authctxt->style ? authctxt->style : "<default>");
75 		authctxt->as = auth_userchallenge(authctxt->user,
76 		    authctxt->style, "auth-ssh", &challenge);
77 		if (authctxt->as == NULL)
78 			challenge = NULL;
79 		debug2("bsdauth_query: <%s>", challenge ? challenge : "empty");
80 	}
81 
82 	if (challenge == NULL)
83 		return -1;
84 
85 	*name = xstrdup("");
86 	*infotxt = xstrdup("");
87 	*numprompts = 1;
88 	*prompts = xcalloc(*numprompts, sizeof(char *));
89 	*echo_on = xcalloc(*numprompts, sizeof(u_int));
90 	(*prompts)[0] = xstrdup(challenge);
91 
92 	return 0;
93 }
94 
95 int
96 bsdauth_respond(void *ctx, u_int numresponses, char **responses)
97 {
98 	Authctxt *authctxt = ctx;
99 	int authok;
100 
101 	if (!authctxt->valid)
102 		return -1;
103 
104 	if (authctxt->as == NULL)
105 		error("bsdauth_respond: no bsd auth session");
106 
107 	if (numresponses != 1)
108 		return -1;
109 
110 	authok = auth_userresponse(authctxt->as, responses[0], 0);
111 	authctxt->as = NULL;
112 	debug3("bsdauth_respond: <%s> = <%d>", responses[0], authok);
113 
114 	return (authok == 0) ? -1 : 0;
115 }
116 
117 static void
118 bsdauth_free_ctx(void *ctx)
119 {
120 	Authctxt *authctxt = ctx;
121 
122 	if (authctxt && authctxt->as) {
123 		auth_close(authctxt->as);
124 		authctxt->as = NULL;
125 	}
126 }
127 
128 KbdintDevice bsdauth_device = {
129 	"bsdauth",
130 	bsdauth_init_ctx,
131 	bsdauth_query,
132 	bsdauth_respond,
133 	bsdauth_free_ctx
134 };
135 
136 KbdintDevice mm_bsdauth_device = {
137 	"bsdauth",
138 	bsdauth_init_ctx,
139 	mm_bsdauth_query,
140 	mm_bsdauth_respond,
141 	bsdauth_free_ctx
142 };
143 #endif
144