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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.bin/ssh/ssh-keysign/../ssh-keysign.c	Lines:	0	149	0.0 %
Date:	2017-11-07	Branches:	0	112	0.0 %


/* $OpenBSD: ssh-keysign.c,v 1.52 2016/02/15 09:47:49 dtucker 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.
 */

#include <sys/types.h>

#include <openssl/evp.h>
#include <openssl/rsa.h>

#include <fcntl.h>
#include <paths.h>
#include <pwd.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include "xmalloc.h"
#include "log.h"
#include "sshkey.h"
#include "ssh.h"
#include "ssh2.h"
#include "misc.h"
#include "sshbuf.h"
#include "authfile.h"
#include "msg.h"
#include "canohost.h"
#include "pathnames.h"
#include "readconf.h"
#include "uidswap.h"
#include "sshkey.h"
#include "ssherr.h"

extern char *__progname;

/* XXX readconf.c needs these */
uid_t original_real_uid;

static int
valid_request(struct passwd *pw, char *host, struct sshkey **ret,
    u_char *data, size_t datalen)
{
	struct sshbuf *b;
	struct sshkey *key = NULL;
	u_char type, *pkblob;
	char *p;
	size_t blen, len;
	char *pkalg, *luser;
	int r, pktype, fail;

	if (ret != NULL)
		*ret = NULL;
	fail = 0;

	if ((b = sshbuf_from(data, datalen)) == NULL)
		fatal("%s: sshbuf_from failed", __func__);

	/* session id, currently limited to SHA1 (20 bytes) or SHA256 (32) */
	if ((r = sshbuf_get_string(b, NULL, &len)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));
	if (len != 20 && len != 32)
		fail++;

	if ((r = sshbuf_get_u8(b, &type)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));
	if (type != SSH2_MSG_USERAUTH_REQUEST)
		fail++;

	/* server user */
	if ((r = sshbuf_skip_string(b)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));

	/* service */
	if ((r = sshbuf_get_cstring(b, &p, NULL)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));
	if (strcmp("ssh-connection", p) != 0)
		fail++;
	free(p);

	/* method */
	if ((r = sshbuf_get_cstring(b, &p, NULL)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));
	if (strcmp("hostbased", p) != 0)
		fail++;
	free(p);

	/* pubkey */
	if ((r = sshbuf_get_cstring(b, &pkalg, NULL)) != 0 ||
	    (r = sshbuf_get_string(b, &pkblob, &blen)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));

	pktype = sshkey_type_from_name(pkalg);
	if (pktype == KEY_UNSPEC)
		fail++;
	else if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
		error("%s: bad key blob: %s", __func__, ssh_err(r));
		fail++;
	} else if (key->type != pktype)
		fail++;
	free(pkalg);
	free(pkblob);

	/* client host name, handle trailing dot */
	if ((r = sshbuf_get_cstring(b, &p, &len)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));
	debug2("%s: check expect chost %s got %s", __func__, host, p);
	if (strlen(host) != len - 1)
		fail++;
	else if (p[len - 1] != '.')
		fail++;
	else if (strncasecmp(host, p, len - 1) != 0)
		fail++;
	free(p);

	/* local user */
	if ((r = sshbuf_get_cstring(b, &luser, NULL)) != 0)
		fatal("%s: buffer error: %s", __func__, ssh_err(r));

	if (strcmp(pw->pw_name, luser) != 0)
		fail++;
	free(luser);

	/* end of message */
	if (sshbuf_len(b) != 0)
		fail++;
	sshbuf_free(b);

	debug3("%s: fail %d", __func__, fail);

	if (fail && key != NULL)
		sshkey_free(key);
	else if (ret != NULL)
		*ret = key;

	return (fail ? -1 : 0);
}

int
main(int argc, char **argv)
{
	struct sshbuf *b;
	Options options;
#define NUM_KEYTYPES 4
	struct sshkey *keys[NUM_KEYTYPES], *key = NULL;
	struct passwd *pw;
	int r, key_fd[NUM_KEYTYPES], i, found, version = 2, fd;
	u_char *signature, *data, rver;
	char *host, *fp;
	size_t slen, dlen;

	ssh_malloc_init();	/* must be called before any mallocs */
	if (pledge("stdio rpath getpw dns id flock cpath wpath", NULL) != 0)
		fatal("%s: pledge: %s", __progname, strerror(errno));

	/* Ensure that stdin and stdout are connected */
	if ((fd = open(_PATH_DEVNULL, O_RDWR)) < 2)
		exit(1);
	/* Leave /dev/null fd iff it is attached to stderr */
	if (fd > 2)
		close(fd);

	i = 0;
	/* XXX This really needs to read sshd_config for the paths */
	key_fd[i++] = open(_PATH_HOST_DSA_KEY_FILE, O_RDONLY);
	key_fd[i++] = open(_PATH_HOST_ECDSA_KEY_FILE, O_RDONLY);
	key_fd[i++] = open(_PATH_HOST_ED25519_KEY_FILE, O_RDONLY);
	key_fd[i++] = open(_PATH_HOST_RSA_KEY_FILE, O_RDONLY);

	original_real_uid = getuid();	/* XXX readconf.c needs this */
	if ((pw = getpwuid(original_real_uid)) == NULL)
		fatal("getpwuid failed");
	pw = pwcopy(pw);

	permanently_set_uid(pw);

#ifdef DEBUG_SSH_KEYSIGN
	log_init("ssh-keysign", SYSLOG_LEVEL_DEBUG3, SYSLOG_FACILITY_AUTH, 0);
#endif

	/* verify that ssh-keysign is enabled by the admin */
	initialize_options(&options);
	(void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, "", "", &options, 0);
	fill_default_options(&options);
	if (options.enable_ssh_keysign != 1)
		fatal("ssh-keysign not enabled in %s",
		    _PATH_HOST_CONFIG_FILE);

	for (i = found = 0; i < NUM_KEYTYPES; i++) {
		if (key_fd[i] != -1)
			found = 1;
	}
	if (found == 0)
		fatal("could not open any host key");

	OpenSSL_add_all_algorithms();

	found = 0;
	for (i = 0; i < NUM_KEYTYPES; i++) {
		keys[i] = NULL;
		if (key_fd[i] == -1)
			continue;
		r = sshkey_load_private_type_fd(key_fd[i], KEY_UNSPEC,
		    NULL, &key, NULL);
		close(key_fd[i]);
		if (r != 0)
			debug("parse key %d: %s", i, ssh_err(r));
		else if (key != NULL) {
			keys[i] = key;
			found = 1;
		}
	}
	if (!found)
		fatal("no hostkey found");

	if (pledge("stdio dns flock rpath cpath wpath", NULL) != 0)
		fatal("%s: pledge: %s", __progname, strerror(errno));

	if ((b = sshbuf_new()) == NULL)
		fatal("%s: sshbuf_new failed", __progname);
	if (ssh_msg_recv(STDIN_FILENO, b) < 0)
		fatal("ssh_msg_recv failed");
	if ((r = sshbuf_get_u8(b, &rver)) != 0)
		fatal("%s: buffer error: %s", __progname, ssh_err(r));
	if (rver != version)
		fatal("bad version: received %d, expected %d", rver, version);
	if ((r = sshbuf_get_u32(b, (u_int *)&fd)) != 0)
		fatal("%s: buffer error: %s", __progname, ssh_err(r));
	if (fd < 0 || fd == STDIN_FILENO || fd == STDOUT_FILENO)
		fatal("bad fd");
	if ((host = get_local_name(fd)) == NULL)
		fatal("cannot get local name for fd");

	if ((r = sshbuf_get_string(b, &data, &dlen)) != 0)
		fatal("%s: buffer error: %s", __progname, ssh_err(r));
	if (valid_request(pw, host, &key, data, dlen) < 0)
		fatal("not a valid request");
	free(host);

	found = 0;
	for (i = 0; i < NUM_KEYTYPES; i++) {
		if (keys[i] != NULL &&
		    sshkey_equal_public(key, keys[i])) {
			found = 1;
			break;
		}
	}
	if (!found) {
		if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
		    SSH_FP_DEFAULT)) == NULL)
			fatal("%s: sshkey_fingerprint failed", __progname);
		fatal("no matching hostkey found for key %s %s",
		    sshkey_type(key), fp ? fp : "");
	}

	if ((r = sshkey_sign(keys[i], &signature, &slen, data, dlen, NULL, 0))
	    != 0)
		fatal("sshkey_sign failed: %s", ssh_err(r));
	free(data);

	/* send reply */
	sshbuf_reset(b);
	if ((r = sshbuf_put_string(b, signature, slen)) != 0)
		fatal("%s: buffer error: %s", __progname, ssh_err(r));
	if (ssh_msg_send(STDOUT_FILENO, version, b) == -1)
		fatal("ssh_msg_send failed");

	return (0);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: ssh-keysign.c,v 1.52 2016/02/15 09:47:49 dtucker Exp $ */
2			/*
3			* Copyright (c) 2002 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 <sys/types.h>
27
28			#include <openssl/evp.h>
29			#include <openssl/rsa.h>
30
31			#include <fcntl.h>
32			#include <paths.h>
33			#include <pwd.h>
34			#include <stdlib.h>
35			#include <string.h>
36			#include <unistd.h>
37			#include <errno.h>
38
39			#include "xmalloc.h"
40			#include "log.h"
41			#include "sshkey.h"
42			#include "ssh.h"
43			#include "ssh2.h"
44			#include "misc.h"
45			#include "sshbuf.h"
46			#include "authfile.h"
47			#include "msg.h"
48			#include "canohost.h"
49			#include "pathnames.h"
50			#include "readconf.h"
51			#include "uidswap.h"
52			#include "sshkey.h"
53			#include "ssherr.h"
54
55			extern char *__progname;
56
57			/* XXX readconf.c needs these */
58			uid_t original_real_uid;
59
60			static int
61			valid_request(struct passwd pw, char host, struct sshkey **ret,
62			u_char *data, size_t datalen)
63			{
64			struct sshbuf *b;
65			struct sshkey *key = NULL;
66			u_char type, *pkblob;
67			char *p;
68			size_t blen, len;
69			char pkalg, luser;
70			int r, pktype, fail;
71
72			if (ret != NULL)
73			*ret = NULL;
74			fail = 0;
75
76			if ((b = sshbuf_from(data, datalen)) == NULL)
77			fatal("%s: sshbuf_from failed", __func__);
78
79			/* session id, currently limited to SHA1 (20 bytes) or SHA256 (32) */
80			if ((r = sshbuf_get_string(b, NULL, &len)) != 0)
81			fatal("%s: buffer error: %s", __func__, ssh_err(r));
82			if (len != 20 && len != 32)
83			fail++;
84
85			if ((r = sshbuf_get_u8(b, &type)) != 0)
86			fatal("%s: buffer error: %s", __func__, ssh_err(r));
87			if (type != SSH2_MSG_USERAUTH_REQUEST)
88			fail++;
89
90			/* server user */
91			if ((r = sshbuf_skip_string(b)) != 0)
92			fatal("%s: buffer error: %s", __func__, ssh_err(r));
93
94			/* service */
95			if ((r = sshbuf_get_cstring(b, &p, NULL)) != 0)
96			fatal("%s: buffer error: %s", __func__, ssh_err(r));
97			if (strcmp("ssh-connection", p) != 0)
98			fail++;
99			free(p);
100
101			/* method */
102			if ((r = sshbuf_get_cstring(b, &p, NULL)) != 0)
103			fatal("%s: buffer error: %s", __func__, ssh_err(r));
104			if (strcmp("hostbased", p) != 0)
105			fail++;
106			free(p);
107
108			/* pubkey */
109			if ((r = sshbuf_get_cstring(b, &pkalg, NULL)) != 0 \|\|
110			(r = sshbuf_get_string(b, &pkblob, &blen)) != 0)
111			fatal("%s: buffer error: %s", __func__, ssh_err(r));
112
113			pktype = sshkey_type_from_name(pkalg);
114			if (pktype == KEY_UNSPEC)
115			fail++;
116			else if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
117			error("%s: bad key blob: %s", __func__, ssh_err(r));
118			fail++;
119			} else if (key->type != pktype)
120			fail++;
121			free(pkalg);
122			free(pkblob);
123
124			/* client host name, handle trailing dot */
125			if ((r = sshbuf_get_cstring(b, &p, &len)) != 0)
126			fatal("%s: buffer error: %s", __func__, ssh_err(r));
127			debug2("%s: check expect chost %s got %s", __func__, host, p);
128			if (strlen(host) != len - 1)
129			fail++;
130			else if (p[len - 1] != '.')
131			fail++;
132			else if (strncasecmp(host, p, len - 1) != 0)
133			fail++;
134			free(p);
135
136			/* local user */
137			if ((r = sshbuf_get_cstring(b, &luser, NULL)) != 0)
138			fatal("%s: buffer error: %s", __func__, ssh_err(r));
139
140			if (strcmp(pw->pw_name, luser) != 0)
141			fail++;
142			free(luser);
143
144			/* end of message */
145			if (sshbuf_len(b) != 0)
146			fail++;
147			sshbuf_free(b);
148
149			debug3("%s: fail %d", __func__, fail);
150
151			if (fail && key != NULL)
152			sshkey_free(key);
153			else if (ret != NULL)
154			*ret = key;
155
156			return (fail ? -1 : 0);
157			}
158
159			int
160			main(int argc, char **argv)
161			{
162			struct sshbuf *b;
163			Options options;
164			#define NUM_KEYTYPES 4
165			struct sshkey keys[NUM_KEYTYPES], key = NULL;
166			struct passwd *pw;
167			int r, key_fd[NUM_KEYTYPES], i, found, version = 2, fd;
168			u_char signature, data, rver;
169			char host, fp;
170			size_t slen, dlen;
171
172			ssh_malloc_init(); /* must be called before any mallocs */
173			if (pledge("stdio rpath getpw dns id flock cpath wpath", NULL) != 0)
174			fatal("%s: pledge: %s", __progname, strerror(errno));
175
176			/* Ensure that stdin and stdout are connected */
177			if ((fd = open(_PATH_DEVNULL, O_RDWR)) < 2)
178			exit(1);
179			/* Leave /dev/null fd iff it is attached to stderr */
180			if (fd > 2)
181			close(fd);
182
183			i = 0;
184			/* XXX This really needs to read sshd_config for the paths */
185			key_fd[i++] = open(_PATH_HOST_DSA_KEY_FILE, O_RDONLY);
186			key_fd[i++] = open(_PATH_HOST_ECDSA_KEY_FILE, O_RDONLY);
187			key_fd[i++] = open(_PATH_HOST_ED25519_KEY_FILE, O_RDONLY);
188			key_fd[i++] = open(_PATH_HOST_RSA_KEY_FILE, O_RDONLY);
189
190			original_real_uid = getuid(); /* XXX readconf.c needs this */
191			if ((pw = getpwuid(original_real_uid)) == NULL)
192			fatal("getpwuid failed");
193			pw = pwcopy(pw);
194
195			permanently_set_uid(pw);
196
197			#ifdef DEBUG_SSH_KEYSIGN
198			log_init("ssh-keysign", SYSLOG_LEVEL_DEBUG3, SYSLOG_FACILITY_AUTH, 0);
199			#endif
200
201			/* verify that ssh-keysign is enabled by the admin */
202			initialize_options(&options);
203			(void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, "", "", &options, 0);
204			fill_default_options(&options);
205			if (options.enable_ssh_keysign != 1)
206			fatal("ssh-keysign not enabled in %s",
207			_PATH_HOST_CONFIG_FILE);
208
209			for (i = found = 0; i < NUM_KEYTYPES; i++) {
210			if (key_fd[i] != -1)
211			found = 1;
212			}
213			if (found == 0)
214			fatal("could not open any host key");
215
216			OpenSSL_add_all_algorithms();
217
218			found = 0;
219			for (i = 0; i < NUM_KEYTYPES; i++) {
220			keys[i] = NULL;
221			if (key_fd[i] == -1)
222			continue;
223			r = sshkey_load_private_type_fd(key_fd[i], KEY_UNSPEC,
224			NULL, &key, NULL);
225			close(key_fd[i]);
226			if (r != 0)
227			debug("parse key %d: %s", i, ssh_err(r));
228			else if (key != NULL) {
229			keys[i] = key;
230			found = 1;
231			}
232			}
233			if (!found)
234			fatal("no hostkey found");
235
236			if (pledge("stdio dns flock rpath cpath wpath", NULL) != 0)
237			fatal("%s: pledge: %s", __progname, strerror(errno));
238
239			if ((b = sshbuf_new()) == NULL)
240			fatal("%s: sshbuf_new failed", __progname);
241			if (ssh_msg_recv(STDIN_FILENO, b) < 0)
242			fatal("ssh_msg_recv failed");
243			if ((r = sshbuf_get_u8(b, &rver)) != 0)
244			fatal("%s: buffer error: %s", __progname, ssh_err(r));
245			if (rver != version)
246			fatal("bad version: received %d, expected %d", rver, version);
247			if ((r = sshbuf_get_u32(b, (u_int *)&fd)) != 0)
248			fatal("%s: buffer error: %s", __progname, ssh_err(r));
249			if (fd < 0 \|\| fd == STDIN_FILENO \|\| fd == STDOUT_FILENO)
250			fatal("bad fd");
251			if ((host = get_local_name(fd)) == NULL)
252			fatal("cannot get local name for fd");
253
254			if ((r = sshbuf_get_string(b, &data, &dlen)) != 0)
255			fatal("%s: buffer error: %s", __progname, ssh_err(r));
256			if (valid_request(pw, host, &key, data, dlen) < 0)
257			fatal("not a valid request");
258			free(host);
259
260			found = 0;
261			for (i = 0; i < NUM_KEYTYPES; i++) {
262			if (keys[i] != NULL &&
263			sshkey_equal_public(key, keys[i])) {
264			found = 1;
265			break;
266			}
267			}
268			if (!found) {
269			if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
270			SSH_FP_DEFAULT)) == NULL)
271			fatal("%s: sshkey_fingerprint failed", __progname);
272			fatal("no matching hostkey found for key %s %s",
273			sshkey_type(key), fp ? fp : "");
274			}
275
276			if ((r = sshkey_sign(keys[i], &signature, &slen, data, dlen, NULL, 0))
277			!= 0)
278			fatal("sshkey_sign failed: %s", ssh_err(r));
279			free(data);
280
281			/* send reply */
282			sshbuf_reset(b);
283			if ((r = sshbuf_put_string(b, signature, slen)) != 0)
284			fatal("%s: buffer error: %s", __progname, ssh_err(r));
285			if (ssh_msg_send(STDOUT_FILENO, version, b) == -1)
286			fatal("ssh_msg_send failed");
287
288			return (0);
289			}