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authorBen Lindstrom <mouring@eviladmin.org>2002-06-06 19:57:33 +0000
committerBen Lindstrom <mouring@eviladmin.org>2002-06-06 19:57:33 +0000
commit1bad256822046e2cc9e3a85a1c622e4ebaa2b97e (patch)
tree555991823221bbb1cbd3c13c1518349a0e06829b
parentf666fec2d553955c26c999cb687877454eeca3ee (diff)
downloadopenssh-git-1bad256822046e2cc9e3a85a1c622e4ebaa2b97e.tar.gz
- markus@cvs.openbsd.org 2002/05/23 19:24:30
[authfile.c authfile.h pathnames.h ssh.c sshconnect.c sshconnect.h sshconnect1.c sshconnect2.c ssh-keysign.8 ssh-keysign.c Makefile.in] add /usr/libexec/ssh-keysign: a setuid helper program for hostbased authentication in protocol v2 (needs to access the hostkeys). Note: Makefile.in untested. Will test after merge is finished.
-rw-r--r--ChangeLog7
-rw-r--r--Makefile.in5
-rw-r--r--authfile.c4
-rw-r--r--authfile.h3
-rw-r--r--pathnames.h7
-rw-r--r--ssh-keysign.858
-rw-r--r--ssh-keysign.c204
-rw-r--r--ssh.c21
-rw-r--r--sshconnect.c8
-rw-r--r--sshconnect.h15
-rw-r--r--sshconnect1.c12
-rw-r--r--sshconnect2.c95
12 files changed, 403 insertions, 36 deletions
diff --git a/ChangeLog b/ChangeLog
index ff710913..8ed0d737 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,6 +16,11 @@
- deraadt@cvs.openbsd.org 2002/05/22 23:18:25
[ssh.c sshd.c]
spelling; abishoff@arc.nasa.gov
+ - markus@cvs.openbsd.org 2002/05/23 19:24:30
+ [authfile.c authfile.h pathnames.h ssh.c sshconnect.c sshconnect.h
+ sshconnect1.c sshconnect2.c ssh-keysign.8 ssh-keysign.c Makefile.in]
+ add /usr/libexec/ssh-keysign: a setuid helper program for hostbased
+ authentication in protocol v2 (needs to access the hostkeys).
20020604
- (stevesk) [channels.c] bug #164 patch from YOSHIFUJI Hideaki (changed
@@ -700,4 +705,4 @@
- (stevesk) entropy.c: typo in debug message
- (djm) ssh-keygen -i needs seeded RNG; report from markus@
-$Id: ChangeLog,v 1.2148 2002/06/06 19:51:58 mouring Exp $
+$Id: ChangeLog,v 1.2149 2002/06/06 19:57:33 mouring Exp $
diff --git a/Makefile.in b/Makefile.in
index e3b14515..ec235f82 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,4 +1,4 @@
-# $Id: Makefile.in,v 1.208 2002/05/13 04:12:05 djm Exp $
+# $Id: Makefile.in,v 1.209 2002/06/06 19:57:33 mouring Exp $
# uncomment if you run a non bourne compatable shell. Ie. csh
#SHELL = @SH@
@@ -125,6 +125,9 @@ ssh-agent$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-agent.o
ssh-keygen$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-keygen.o
$(LD) -o $@ ssh-keygen.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
+ssh-keysign$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-keysign.o
+ $(LD) -o $@ ssh-keysign.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
+
ssh-keyscan$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-keyscan.o
$(LD) -o $@ ssh-keyscan.o $(LDFLAGS) -lssh -lopenbsd-compat -lssh $(LIBS)
diff --git a/authfile.c b/authfile.c
index de8b1022..6d936de5 100644
--- a/authfile.c
+++ b/authfile.c
@@ -36,7 +36,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: authfile.c,v 1.48 2002/02/28 15:46:33 markus Exp $");
+RCSID("$OpenBSD: authfile.c,v 1.49 2002/05/23 19:24:30 markus Exp $");
#include <openssl/err.h>
#include <openssl/evp.h>
@@ -421,7 +421,7 @@ fail:
return NULL;
}
-static Key *
+Key *
key_load_private_pem(int fd, int type, const char *passphrase,
char **commentp)
{
diff --git a/authfile.h b/authfile.h
index c614ca12..7f92701e 100644
--- a/authfile.h
+++ b/authfile.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: authfile.h,v 1.9 2002/03/04 17:27:39 stevesk Exp $ */
+/* $OpenBSD: authfile.h,v 1.10 2002/05/23 19:24:30 markus Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -20,5 +20,6 @@ Key *key_load_public(const char *, char **);
Key *key_load_public_type(int, const char *, char **);
Key *key_load_private(const char *, const char *, char **);
Key *key_load_private_type(int, const char *, const char *, char **);
+Key *key_load_private_pem(int, int, const char *, char **);
#endif
diff --git a/pathnames.h b/pathnames.h
index 691293c3..89e22c77 100644
--- a/pathnames.h
+++ b/pathnames.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: pathnames.h,v 1.12 2002/03/19 03:03:43 stevesk Exp $ */
+/* $OpenBSD: pathnames.h,v 1.13 2002/05/23 19:24:30 markus Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -120,6 +120,11 @@
#define _PATH_SSH_ASKPASS_DEFAULT "/usr/X11R6/bin/ssh-askpass"
#endif
+/* Location of ssh-keysign for hostbased authentication */
+#ifndef _PATH_SSH_KEY_SIGN
+#define _PATH_SSH_KEY_SIGN "/usr/libexec/ssh-keysign"
+#endif
+
/* xauth for X11 forwarding */
#ifndef _PATH_XAUTH
#define _PATH_XAUTH "/usr/X11R6/bin/xauth"
diff --git a/ssh-keysign.8 b/ssh-keysign.8
new file mode 100644
index 00000000..fccbd7c2
--- /dev/null
+++ b/ssh-keysign.8
@@ -0,0 +1,58 @@
+.\" $OpenBSD: ssh-keysign.8,v 1.1 2002/05/25 08:16:59 markus Exp $
+.\"
+.\" Copyright (c) 2002 Markus Friedl. All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\" notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\" notice, this list of conditions and the following disclaimer in the
+.\" documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.Dd May 24, 2002
+.Dt SSH-KEYSIGN 8
+.Os
+.Sh NAME
+.Nm ssh-keysign
+.Nd ssh helper program for hostbased authentication
+.Sh SYNOPSIS
+.Nm ssh-keysign
+.Sh DESCRIPTION
+.Nm
+is used by
+.Xr ssh 1
+to access the local host keys during hostbased authentication with
+SSH protocol version 2.
+Since the host keys are readable only by root
+.Nm
+must be setuid root.
+.Nm
+is not intended to be invoked by the user, but from
+.Xr ssh 1 .
+See
+.Xr ssh 1
+and
+.Xr sshd 8
+for more information about hostbased authentication.
+.Sh SEE ALSO
+.Xr ssh 1 ,
+.Xr sshd 8
+.Sh AUTHORS
+Markus Friedl <markus@openbsd.org>
+.Sh HISTORY
+.Nm
+first appeared in
+.Ox 3.2 .
diff --git a/ssh-keysign.c b/ssh-keysign.c
new file mode 100644
index 00000000..da630708
--- /dev/null
+++ b/ssh-keysign.c
@@ -0,0 +1,204 @@
+/*
+ * Copyright (c) 2002 Markus Friedl. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "includes.h"
+RCSID("$OpenBSD: ssh-keysign.c,v 1.2 2002/05/31 10:30:33 markus Exp $");
+
+#include <openssl/evp.h>
+
+#include "log.h"
+#include "key.h"
+#include "ssh2.h"
+#include "misc.h"
+#include "xmalloc.h"
+#include "buffer.h"
+#include "bufaux.h"
+#include "authfile.h"
+#include "msg.h"
+#include "canohost.h"
+#include "pathnames.h"
+
+static int
+valid_request(struct passwd *pw, char *host, Key **ret, u_char *data,
+ u_int datalen)
+{
+ Buffer b;
+ Key *key;
+ u_char *pkblob;
+ u_int blen, len;
+ char *pkalg, *p;
+ int pktype, fail;
+
+ fail = 0;
+
+ buffer_init(&b);
+ buffer_append(&b, data, datalen);
+
+ /* session id */
+ buffer_skip_string(&b);
+ if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
+ fail++;
+
+ /* server user */
+ buffer_skip_string(&b);
+
+ /* service */
+ p = buffer_get_string(&b, NULL);
+ if (strcmp("ssh-connection", p) != 0)
+ fail++;
+ xfree(p);
+
+ /* method */
+ p = buffer_get_string(&b, NULL);
+ if (strcmp("hostbased", p) != 0)
+ fail++;
+ xfree(p);
+
+ /* pubkey */
+ pkalg = buffer_get_string(&b, NULL);
+ pkblob = buffer_get_string(&b, &blen);
+
+ pktype = key_type_from_name(pkalg);
+ if (pktype == KEY_UNSPEC)
+ fail++;
+ else if ((key = key_from_blob(pkblob, blen)) == NULL)
+ fail++;
+ else if (key->type != pktype)
+ fail++;
+ xfree(pkalg);
+ xfree(pkblob);
+
+ /* client host name, handle trailing dot */
+ p = buffer_get_string(&b, &len);
+ debug2("valid_request: check expect chost %s got %s", host, p);
+ if (strlen(host) != len - 1)
+ fail++;
+ else if (p[len - 1] != '.')
+ fail++;
+ else if (strncasecmp(host, p, len - 1) != 0)
+ fail++;
+ xfree(p);
+
+ /* local user */
+ p = buffer_get_string(&b, NULL);
+
+ if (strcmp(pw->pw_name, p) != 0)
+ fail++;
+ xfree(p);
+
+ /* end of message */
+ if (buffer_len(&b) != 0)
+ fail++;
+
+ debug3("valid_request: fail %d", fail);
+
+ if (fail && key != NULL)
+ key_free(key);
+ else
+ *ret = key;
+
+ return (fail ? -1 : 0);
+}
+
+int
+main(int argc, char **argv)
+{
+ Buffer b;
+ Key *keys[2], *key;
+ struct passwd *pw;
+ int key_fd[2], i, found, version = 2, fd;
+ u_char *signature, *data;
+ char *host;
+ u_int slen, dlen;
+
+ key_fd[0] = open(_PATH_HOST_RSA_KEY_FILE, O_RDONLY);
+ key_fd[1] = open(_PATH_HOST_DSA_KEY_FILE, O_RDONLY);
+
+ seteuid(getuid());
+ setuid(getuid());
+
+#ifdef DEBUG_SSH_KEYSIGN
+ log_init("ssh-keysign", SYSLOG_LEVEL_DEBUG3, SYSLOG_FACILITY_AUTH, 0);
+#endif
+
+ if (key_fd[0] == -1 && key_fd[1] == -1)
+ fatal("could not open any host key");
+
+ if ((pw = getpwuid(getuid())) == NULL)
+ fatal("getpwuid failed");
+ pw = pwcopy(pw);
+
+ SSLeay_add_all_algorithms();
+
+ found = 0;
+ for (i = 0; i < 2; i++) {
+ keys[i] = NULL;
+ if (key_fd[i] == -1)
+ continue;
+ keys[i] = key_load_private_pem(key_fd[i], KEY_UNSPEC,
+ NULL, NULL);
+ close(key_fd[i]);
+ if (keys[i] != NULL)
+ found = 1;
+ }
+ if (!found)
+ fatal("no hostkey found");
+
+ buffer_init(&b);
+ if (msg_recv(STDIN_FILENO, &b) < 0)
+ fatal("msg_recv failed");
+ if (buffer_get_char(&b) != version)
+ fatal("bad version");
+ fd = buffer_get_int(&b);
+ if ((fd == STDIN_FILENO) || (fd == STDOUT_FILENO))
+ fatal("bad fd");
+ if ((host = get_local_name(fd)) == NULL)
+ fatal("cannot get sockname for fd");
+
+ data = buffer_get_string(&b, &dlen);
+ if (valid_request(pw, host, &key, data, dlen) < 0)
+ fatal("not a valid request");
+ xfree(data);
+ xfree(host);
+
+ found = 0;
+ for (i = 0; i < 2; i++) {
+ if (keys[i] != NULL &&
+ key_equal(key, keys[i])) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found)
+ fatal("no matching hostkey found");
+
+ if (key_sign(keys[i], &signature, &slen, data, dlen) != 0)
+ fatal("key_sign failed");
+
+ /* send reply */
+ buffer_clear(&b);
+ buffer_put_string(&b, signature, slen);
+ msg_send(STDOUT_FILENO, version, &b);
+
+ return (0);
+}
diff --git a/ssh.c b/ssh.c
index 4b82d1e7..2e479d52 100644
--- a/ssh.c
+++ b/ssh.c
@@ -40,7 +40,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: ssh.c,v 1.172 2002/05/22 23:18:25 deraadt Exp $");
+RCSID("$OpenBSD: ssh.c,v 1.173 2002/05/23 19:24:30 markus Exp $");
#include <openssl/evp.h>
#include <openssl/err.h>
@@ -132,10 +132,7 @@ char *host;
struct sockaddr_storage hostaddr;
/* Private host keys. */
-struct {
- Key **keys;
- int nkeys;
-} sensitive_data;
+Sensitive sensitive_data;
/* Original real UID. */
uid_t original_real_uid;
@@ -689,6 +686,7 @@ again:
*/
sensitive_data.nkeys = 0;
sensitive_data.keys = NULL;
+ sensitive_data.external_keysign = 0;
if (!cerr && (options.rhosts_rsa_authentication ||
options.hostbased_authentication)) {
sensitive_data.nkeys = 3;
@@ -699,6 +697,16 @@ again:
_PATH_HOST_DSA_KEY_FILE, "", NULL);
sensitive_data.keys[2] = key_load_private_type(KEY_RSA,
_PATH_HOST_RSA_KEY_FILE, "", NULL);
+
+ if (sensitive_data.keys[0] == NULL &&
+ sensitive_data.keys[1] == NULL &&
+ sensitive_data.keys[2] == NULL) {
+ sensitive_data.keys[1] = key_load_public(
+ _PATH_HOST_DSA_KEY_FILE, NULL);
+ sensitive_data.keys[2] = key_load_public(
+ _PATH_HOST_RSA_KEY_FILE, NULL);
+ sensitive_data.external_keysign = 1;
+ }
}
/*
* Get rid of any extra privileges that we may have. We will no
@@ -758,8 +766,7 @@ again:
signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
/* Log into the remote system. This never returns if the login fails. */
- ssh_login(sensitive_data.keys, sensitive_data.nkeys,
- host, (struct sockaddr *)&hostaddr, pw);
+ ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, pw);
/* We no longer need the private host keys. Clear them now. */
if (sensitive_data.nkeys != 0) {
diff --git a/sshconnect.c b/sshconnect.c
index 5bb50e0e..7af0b9a8 100644
--- a/sshconnect.c
+++ b/sshconnect.c
@@ -13,7 +13,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect.c,v 1.119 2002/01/21 15:13:51 markus Exp $");
+RCSID("$OpenBSD: sshconnect.c,v 1.120 2002/05/23 19:24:30 markus Exp $");
#include <openssl/bn.h>
@@ -844,7 +844,7 @@ verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
* This function does not require super-user privileges.
*/
void
-ssh_login(Key **keys, int nkeys, const char *orighost,
+ssh_login(Sensitive *sensitive, const char *orighost,
struct sockaddr *hostaddr, struct passwd *pw)
{
char *host, *cp;
@@ -869,10 +869,10 @@ ssh_login(Key **keys, int nkeys, const char *orighost,
/* authenticate user */
if (compat20) {
ssh_kex2(host, hostaddr);
- ssh_userauth2(local_user, server_user, host, keys, nkeys);
+ ssh_userauth2(local_user, server_user, host, sensitive);
} else {
ssh_kex(host, hostaddr);
- ssh_userauth1(local_user, server_user, host, keys, nkeys);
+ ssh_userauth1(local_user, server_user, host, sensitive);
}
}
diff --git a/sshconnect.h b/sshconnect.h
index b475adde..ad34ee64 100644
--- a/sshconnect.h
+++ b/sshconnect.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect.h,v 1.13 2001/10/08 19:05:05 markus Exp $ */
+/* $OpenBSD: sshconnect.h,v 1.14 2002/05/23 19:24:30 markus Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. All rights reserved.
@@ -26,20 +26,27 @@
#ifndef SSHCONNECT_H
#define SSHCONNECT_H
+typedef struct Sensitive Sensitive;
+struct Sensitive {
+ Key **keys;
+ int nkeys;
+ int external_keysign;
+};
+
int
ssh_connect(const char *, struct sockaddr_storage *, u_short, int, int,
int, struct passwd *, const char *);
void
-ssh_login(Key **, int, const char *, struct sockaddr *, struct passwd *);
+ssh_login(Sensitive *, const char *, struct sockaddr *, struct passwd *);
int verify_host_key(char *, struct sockaddr *, Key *);
void ssh_kex(char *, struct sockaddr *);
void ssh_kex2(char *, struct sockaddr *);
-void ssh_userauth1(const char *, const char *, char *, Key **, int);
-void ssh_userauth2(const char *, const char *, char *, Key **, int);
+void ssh_userauth1(const char *, const char *, char *, Sensitive *);
+void ssh_userauth2(const char *, const char *, char *, Sensitive *);
void ssh_put_password(char *);
diff --git a/sshconnect1.c b/sshconnect1.c
index d2024a2b..e28b7fc7 100644
--- a/sshconnect1.c
+++ b/sshconnect1.c
@@ -13,7 +13,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect1.c,v 1.50 2002/04/21 16:25:06 stevesk Exp $");
+RCSID("$OpenBSD: sshconnect1.c,v 1.51 2002/05/23 19:24:30 markus Exp $");
#include <openssl/bn.h>
#include <openssl/md5.h>
@@ -1138,7 +1138,7 @@ ssh_kex(char *host, struct sockaddr *hostaddr)
*/
void
ssh_userauth1(const char *local_user, const char *server_user, char *host,
- Key **keys, int nkeys)
+ Sensitive *sensitive)
{
#ifdef KRB5
krb5_context context = NULL;
@@ -1224,9 +1224,11 @@ ssh_userauth1(const char *local_user, const char *server_user, char *host,
*/
if ((supported_authentications & (1 << SSH_AUTH_RHOSTS_RSA)) &&
options.rhosts_rsa_authentication) {
- for (i = 0; i < nkeys; i++) {
- if (keys[i] != NULL && keys[i]->type == KEY_RSA1 &&
- try_rhosts_rsa_authentication(local_user, keys[i]))
+ for (i = 0; i < sensitive->nkeys; i++) {
+ if (sensitive->keys[i] != NULL &&
+ sensitive->keys[i]->type == KEY_RSA1 &&
+ try_rhosts_rsa_authentication(local_user,
+ sensitive->keys[i]))
goto success;
}
}
diff --git a/sshconnect2.c b/sshconnect2.c
index 1ee92ab0..2736856f 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -23,7 +23,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect2.c,v 1.99 2002/03/26 15:58:46 markus Exp $");
+RCSID("$OpenBSD: sshconnect2.c,v 1.100 2002/05/23 19:24:30 markus Exp $");
#include "ssh.h"
#include "ssh2.h"
@@ -45,6 +45,8 @@ RCSID("$OpenBSD: sshconnect2.c,v 1.99 2002/03/26 15:58:46 markus Exp $");
#include "match.h"
#include "dispatch.h"
#include "canohost.h"
+#include "msg.h"
+#include "pathnames.h"
/* import */
extern char *client_version_string;
@@ -154,8 +156,7 @@ struct Authctxt {
int last_key_hint;
AuthenticationConnection *agent;
/* hostbased */
- Key **keys;
- int nkeys;
+ Sensitive *sensitive;
/* kbd-interactive */
int info_req_seen;
};
@@ -215,7 +216,7 @@ Authmethod authmethods[] = {
void
ssh_userauth2(const char *local_user, const char *server_user, char *host,
- Key **keys, int nkeys)
+ Sensitive *sensitive)
{
Authctxt authctxt;
int type;
@@ -255,8 +256,7 @@ ssh_userauth2(const char *local_user, const char *server_user, char *host,
authctxt.success = 0;
authctxt.method = authmethod_lookup("none");
authctxt.authlist = NULL;
- authctxt.keys = keys;
- authctxt.nkeys = nkeys;
+ authctxt.sensitive = sensitive;
authctxt.info_req_seen = 0;
if (authctxt.method == NULL)
fatal("ssh_userauth2: internal error: cannot send userauth none request");
@@ -893,6 +893,75 @@ input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
packet_send();
}
+static int
+ssh_keysign(
+ Key *key,
+ u_char **sigp, u_int *lenp,
+ u_char *data, u_int datalen)
+{
+ Buffer b;
+ pid_t pid;
+ int to[2], from[2], status, version = 1;
+
+ debug("ssh_keysign called");
+
+ if (fflush(stdout) != 0)
+ error("ssh_keysign: fflush: %s", strerror(errno));
+ if (pipe(to) < 0) {
+ error("ssh_keysign: pipe: %s", strerror(errno));
+ return -1;
+ }
+ if (pipe(from) < 0) {
+ error("ssh_keysign: pipe: %s", strerror(errno));
+ return -1;
+ }
+ if ((pid = fork()) < 0) {
+ error("ssh_keysign: fork: %s", strerror(errno));
+ return -1;
+ }
+ if (pid == 0) {
+ seteuid(getuid());
+ setuid(getuid());
+ close(from[0]);
+ if (dup2(from[1], STDOUT_FILENO) < 0)
+ fatal("ssh_keysign: dup2: %s", strerror(errno));
+ close(to[1]);
+ if (dup2(to[0], STDIN_FILENO) < 0)
+ fatal("ssh_keysign: dup2: %s", strerror(errno));
+ execlp(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
+ fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
+ strerror(errno));
+ }
+ close(from[1]);
+ close(to[0]);
+
+ buffer_init(&b);
+ buffer_put_string(&b, data, datalen);
+ msg_send(to[1], version, &b);
+
+ if (msg_recv(from[0], &b) < 0) {
+ debug("ssh_keysign: no reply");
+ buffer_clear(&b);
+ return -1;
+ }
+ if (buffer_get_char(&b) != version) {
+ debug("ssh_keysign: bad version");
+ buffer_clear(&b);
+ return -1;
+ }
+ *sigp = buffer_get_string(&b, lenp);
+ buffer_clear(&b);
+
+ close(from[0]);
+ close(to[1]);
+
+ while (waitpid(pid, &status, 0) < 0)
+ if (errno != EINTR)
+ break;
+
+ return 0;
+}
+
/*
* this will be move to an external program (ssh-keysign) ASAP. ssh-keysign
* will be setuid-root and the sbit can be removed from /usr/bin/ssh.
@@ -901,6 +970,7 @@ int
userauth_hostbased(Authctxt *authctxt)
{
Key *private = NULL;
+ Sensitive *sensitive = authctxt->sensitive;
Buffer b;
u_char *signature, *blob;
char *chost, *pkalg, *p;
@@ -909,12 +979,12 @@ userauth_hostbased(Authctxt *authctxt)
int ok, i, len, found = 0;
/* check for a useful key */
- for (i = 0; i < authctxt->nkeys; i++) {
- private = authctxt->keys[i];
+ for (i = 0; i < sensitive->nkeys; i++) {
+ private = sensitive->keys[i];
if (private && private->type != KEY_RSA1) {
found = 1;
/* we take and free the key */
- authctxt->keys[i] = NULL;
+ sensitive->keys[i] = NULL;
break;
}
}
@@ -956,7 +1026,12 @@ userauth_hostbased(Authctxt *authctxt)
#ifdef DEBUG_PK
buffer_dump(&b);
#endif
- ok = key_sign(private, &signature, &slen, buffer_ptr(&b), buffer_len(&b));
+ if (sensitive->external_keysign)
+ ok = ssh_keysign(private, &signature, &slen,
+ buffer_ptr(&b), buffer_len(&b));
+ else
+ ok = key_sign(private, &signature, &slen,
+ buffer_ptr(&b), buffer_len(&b));
key_free(private);
buffer_free(&b);
if (ok != 0) {