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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.bin/ssh/lib/../ssh_api.c	Lines:	0	233	0.0 %
Date:	2017-11-07	Branches:	0	164	0.0 %


/* $OpenBSD: ssh_api.c,v 1.8 2017/04/30 23:13:25 djm Exp $ */
/*
 * Copyright (c) 2012 Markus Friedl.  All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "ssh_api.h"
#include "compat.h"
#include "log.h"
#include "authfile.h"
#include "sshkey.h"
#include "misc.h"
#include "ssh2.h"
#include "version.h"
#include "myproposal.h"
#include "ssherr.h"
#include "sshbuf.h"

#include <string.h>

int	_ssh_exchange_banner(struct ssh *);
int	_ssh_send_banner(struct ssh *, char **);
int	_ssh_read_banner(struct ssh *, char **);
int	_ssh_order_hostkeyalgs(struct ssh *);
int	_ssh_verify_host_key(struct sshkey *, struct ssh *);
struct sshkey *_ssh_host_public_key(int, int, struct ssh *);
struct sshkey *_ssh_host_private_key(int, int, struct ssh *);
int	_ssh_host_key_sign(struct sshkey *, struct sshkey *,
    u_char **, size_t *, const u_char *, size_t, const char *, u_int);

/*
 * stubs for the server side implementation of kex.
 * disable privsep so our stubs will never be called.
 */
int	use_privsep = 0;
int	mm_sshkey_sign(struct sshkey *, u_char **, u_int *,
    u_char *, u_int, char *, u_int);
DH	*mm_choose_dh(int, int, int);

/* Define these two variables here so that they are part of the library */
u_char *session_id2 = NULL;
u_int session_id2_len = 0;

int
mm_sshkey_sign(struct sshkey *key, u_char **sigp, u_int *lenp,
    u_char *data, u_int datalen, char *alg, u_int compat)
{
	return (-1);
}

DH *
mm_choose_dh(int min, int nbits, int max)
{
	return (NULL);
}

/* API */

int
ssh_init(struct ssh **sshp, int is_server, struct kex_params *kex_params)
{
        char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
	struct ssh *ssh;
	char **proposal;
	static int called;
	int r;

	if (!called) {
		OpenSSL_add_all_algorithms();
		called = 1;
	}

	if ((ssh = ssh_packet_set_connection(NULL, -1, -1)) == NULL)
		return SSH_ERR_ALLOC_FAIL;
	if (is_server)
		ssh_packet_set_server(ssh);

	/* Initialize key exchange */
	proposal = kex_params ? kex_params->proposal : myproposal;
	if ((r = kex_new(ssh, proposal, &ssh->kex)) != 0) {
		ssh_free(ssh);
		return r;
	}
	ssh->kex->server = is_server;
	if (is_server) {
#ifdef WITH_OPENSSL
		ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
		ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
		ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
		ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
		ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
		ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
		ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
		ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
#endif /* WITH_OPENSSL */
		ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_server;
		ssh->kex->load_host_public_key=&_ssh_host_public_key;
		ssh->kex->load_host_private_key=&_ssh_host_private_key;
		ssh->kex->sign=&_ssh_host_key_sign;
	} else {
#ifdef WITH_OPENSSL
		ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
		ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
		ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_client;
		ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_client;
		ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_client;
		ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
		ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
		ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
#endif /* WITH_OPENSSL */
		ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_client;
		ssh->kex->verify_host_key =&_ssh_verify_host_key;
	}
	*sshp = ssh;
	return 0;
}

void
ssh_free(struct ssh *ssh)
{
	struct key_entry *k;

	ssh_packet_close(ssh);
	/*
	 * we've only created the public keys variants in case we
	 * are a acting as a server.
	 */
	while ((k = TAILQ_FIRST(&ssh->public_keys)) != NULL) {
		TAILQ_REMOVE(&ssh->public_keys, k, next);
		if (ssh->kex && ssh->kex->server)
			sshkey_free(k->key);
		free(k);
	}
	while ((k = TAILQ_FIRST(&ssh->private_keys)) != NULL) {
		TAILQ_REMOVE(&ssh->private_keys, k, next);
		free(k);
	}
	if (ssh->kex)
		kex_free(ssh->kex);
	free(ssh);
}

void
ssh_set_app_data(struct ssh *ssh, void *app_data)
{
	ssh->app_data = app_data;
}

void *
ssh_get_app_data(struct ssh *ssh)
{
	return ssh->app_data;
}

/* Returns < 0 on error, 0 otherwise */
int
ssh_add_hostkey(struct ssh *ssh, struct sshkey *key)
{
	struct sshkey *pubkey = NULL;
	struct key_entry *k = NULL, *k_prv = NULL;
	int r;

	if (ssh->kex->server) {
		if ((r = sshkey_from_private(key, &pubkey)) != 0)
			return r;
		if ((k = malloc(sizeof(*k))) == NULL ||
		    (k_prv = malloc(sizeof(*k_prv))) == NULL) {
			free(k);
			sshkey_free(pubkey);
			return SSH_ERR_ALLOC_FAIL;
		}
		k_prv->key = key;
		TAILQ_INSERT_TAIL(&ssh->private_keys, k_prv, next);

		/* add the public key, too */
		k->key = pubkey;
		TAILQ_INSERT_TAIL(&ssh->public_keys, k, next);
		r = 0;
	} else {
		if ((k = malloc(sizeof(*k))) == NULL)
			return SSH_ERR_ALLOC_FAIL;
		k->key = key;
		TAILQ_INSERT_TAIL(&ssh->public_keys, k, next);
		r = 0;
	}

	return r;
}

int
ssh_set_verify_host_key_callback(struct ssh *ssh,
    int (*cb)(struct sshkey *, struct ssh *))
{
	if (cb == NULL || ssh->kex == NULL)
		return SSH_ERR_INVALID_ARGUMENT;

	ssh->kex->verify_host_key = cb;

	return 0;
}

int
ssh_input_append(struct ssh *ssh, const u_char *data, size_t len)
{
	return sshbuf_put(ssh_packet_get_input(ssh), data, len);
}

int
ssh_packet_next(struct ssh *ssh, u_char *typep)
{
	int r;
	u_int32_t seqnr;
	u_char type;

	/*
	 * Try to read a packet. Return SSH_MSG_NONE if no packet or not
	 * enough data.
	 */
	*typep = SSH_MSG_NONE;
	if (ssh->kex->client_version_string == NULL ||
	    ssh->kex->server_version_string == NULL)
		return _ssh_exchange_banner(ssh);
	/*
	 * If we enough data and a dispatch function then
	 * call the function and get the next packet.
	 * Otherwise return the packet type to the caller so it
	 * can decide how to go on.
	 *
	 * We will only call the dispatch function for:
	 *     20-29    Algorithm negotiation
	 *     30-49    Key exchange method specific (numbers can be reused for
	 *              different authentication methods)
	 */
	for (;;) {
		if ((r = ssh_packet_read_poll2(ssh, &type, &seqnr)) != 0)
			return r;
		if (type > 0 && type < DISPATCH_MAX &&
		    type >= SSH2_MSG_KEXINIT && type <= SSH2_MSG_TRANSPORT_MAX &&
		    ssh->dispatch[type] != NULL) {
			if ((r = (*ssh->dispatch[type])(type, seqnr, ssh)) != 0)
				return r;
		} else {
			*typep = type;
			return 0;
		}
	}
}

const u_char *
ssh_packet_payload(struct ssh *ssh, size_t *lenp)
{
	return sshpkt_ptr(ssh, lenp);
}

int
ssh_packet_put(struct ssh *ssh, int type, const u_char *data, size_t len)
{
	int r;

	if ((r = sshpkt_start(ssh, type)) != 0 ||
	    (r = sshpkt_put(ssh, data, len)) != 0 ||
	    (r = sshpkt_send(ssh)) != 0)
		return r;
	return 0;
}

const u_char *
ssh_output_ptr(struct ssh *ssh, size_t *len)
{
	struct sshbuf *output = ssh_packet_get_output(ssh);

	*len = sshbuf_len(output);
	return sshbuf_ptr(output);
}

int
ssh_output_consume(struct ssh *ssh, size_t len)
{
	return sshbuf_consume(ssh_packet_get_output(ssh), len);
}

int
ssh_output_space(struct ssh *ssh, size_t len)
{
	return (0 == sshbuf_check_reserve(ssh_packet_get_output(ssh), len));
}

int
ssh_input_space(struct ssh *ssh, size_t len)
{
	return (0 == sshbuf_check_reserve(ssh_packet_get_input(ssh), len));
}

/* Read other side's version identification. */
int
_ssh_read_banner(struct ssh *ssh, char **bannerp)
{
	struct sshbuf *input;
	const char *s;
	char buf[256], remote_version[256];	/* must be same size! */
	const char *mismatch = "Protocol mismatch.\r\n";
	int r, remote_major, remote_minor;
	size_t i, n, j, len;

	*bannerp = NULL;
	input = ssh_packet_get_input(ssh);
	len = sshbuf_len(input);
	s = (const char *)sshbuf_ptr(input);
	for (j = n = 0;;) {
		for (i = 0; i < sizeof(buf) - 1; i++) {
			if (j >= len)
				return (0);
			buf[i] = s[j++];
			if (buf[i] == '\r') {
				buf[i] = '\n';
				buf[i + 1] = 0;
				continue;		/**XXX wait for \n */
			}
			if (buf[i] == '\n') {
				buf[i + 1] = 0;
				break;
			}
		}
		buf[sizeof(buf) - 1] = 0;
		if (strncmp(buf, "SSH-", 4) == 0)
			break;
		debug("ssh_exchange_identification: %s", buf);
		if (ssh->kex->server || ++n > 65536) {
			if ((r = sshbuf_put(ssh_packet_get_output(ssh),
			   mismatch, strlen(mismatch))) != 0)
				return r;
			return SSH_ERR_NO_PROTOCOL_VERSION;
		}
	}
	if ((r = sshbuf_consume(input, j)) != 0)
		return r;

	/*
	 * Check that the versions match.  In future this might accept
	 * several versions and set appropriate flags to handle them.
	 */
	if (sscanf(buf, "SSH-%d.%d-%[^\n]\n",
	    &remote_major, &remote_minor, remote_version) != 3)
		return SSH_ERR_INVALID_FORMAT;
	debug("Remote protocol version %d.%d, remote software version %.100s",
	    remote_major, remote_minor, remote_version);

	ssh->compat = compat_datafellows(remote_version);
	if  (remote_major == 1 && remote_minor == 99) {
		remote_major = 2;
		remote_minor = 0;
	}
	if (remote_major != 2)
		return SSH_ERR_PROTOCOL_MISMATCH;
	chop(buf);
	debug("Remote version string %.100s", buf);
	if ((*bannerp = strdup(buf)) == NULL)
		return SSH_ERR_ALLOC_FAIL;
	return 0;
}

/* Send our own protocol version identification. */
int
_ssh_send_banner(struct ssh *ssh, char **bannerp)
{
	char buf[256];
	int r;

	snprintf(buf, sizeof buf, "SSH-2.0-%.100s\r\n", SSH_VERSION);
	if ((r = sshbuf_put(ssh_packet_get_output(ssh), buf, strlen(buf))) != 0)
		return r;
	chop(buf);
	debug("Local version string %.100s", buf);
	if ((*bannerp = strdup(buf)) == NULL)
		return SSH_ERR_ALLOC_FAIL;
	return 0;
}

int
_ssh_exchange_banner(struct ssh *ssh)
{
	struct kex *kex = ssh->kex;
	int r;

	/*
	 * if _ssh_read_banner() cannot parse a full version string
	 * it will return NULL and we end up calling it again.
	 */

	r = 0;
	if (kex->server) {
		if (kex->server_version_string == NULL)
			r = _ssh_send_banner(ssh, &kex->server_version_string);
		if (r == 0 &&
		    kex->server_version_string != NULL &&
		    kex->client_version_string == NULL)
			r = _ssh_read_banner(ssh, &kex->client_version_string);
	} else {
		if (kex->server_version_string == NULL)
			r = _ssh_read_banner(ssh, &kex->server_version_string);
		if (r == 0 &&
		    kex->server_version_string != NULL &&
		    kex->client_version_string == NULL)
			r = _ssh_send_banner(ssh, &kex->client_version_string);
	}
	if (r != 0)
		return r;
	/* start initial kex as soon as we have exchanged the banners */
	if (kex->server_version_string != NULL &&
	    kex->client_version_string != NULL) {
		if ((r = _ssh_order_hostkeyalgs(ssh)) != 0 ||
		    (r = kex_send_kexinit(ssh)) != 0)
			return r;
	}
	return 0;
}

struct sshkey *
_ssh_host_public_key(int type, int nid, struct ssh *ssh)
{
	struct key_entry *k;

	debug3("%s: need %d", __func__, type);
	TAILQ_FOREACH(k, &ssh->public_keys, next) {
		debug3("%s: check %s", __func__, sshkey_type(k->key));
		if (k->key->type == type &&
		    (type != KEY_ECDSA || k->key->ecdsa_nid == nid))
			return (k->key);
	}
	return (NULL);
}

struct sshkey *
_ssh_host_private_key(int type, int nid, struct ssh *ssh)
{
	struct key_entry *k;

	debug3("%s: need %d", __func__, type);
	TAILQ_FOREACH(k, &ssh->private_keys, next) {
		debug3("%s: check %s", __func__, sshkey_type(k->key));
		if (k->key->type == type &&
		    (type != KEY_ECDSA || k->key->ecdsa_nid == nid))
			return (k->key);
	}
	return (NULL);
}

int
_ssh_verify_host_key(struct sshkey *hostkey, struct ssh *ssh)
{
	struct key_entry *k;

	debug3("%s: need %s", __func__, sshkey_type(hostkey));
	TAILQ_FOREACH(k, &ssh->public_keys, next) {
		debug3("%s: check %s", __func__, sshkey_type(k->key));
		if (sshkey_equal_public(hostkey, k->key))
			return (0);	/* ok */
	}
	return (-1);	/* failed */
}

/* offer hostkey algorithms in kexinit depending on registered keys */
int
_ssh_order_hostkeyalgs(struct ssh *ssh)
{
	struct key_entry *k;
	char *orig, *avail, *oavail = NULL, *alg, *replace = NULL;
	char **proposal;
	size_t maxlen;
	int ktype, r;

	/* XXX we de-serialize ssh->kex->my, modify it, and change it */
	if ((r = kex_buf2prop(ssh->kex->my, NULL, &proposal)) != 0)
		return r;
	orig = proposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
	if ((oavail = avail = strdup(orig)) == NULL) {
		r = SSH_ERR_ALLOC_FAIL;
		goto out;
	}
	maxlen = strlen(avail) + 1;
	if ((replace = calloc(1, maxlen)) == NULL) {
		r = SSH_ERR_ALLOC_FAIL;
		goto out;
	}
	*replace = '\0';
	while ((alg = strsep(&avail, ",")) && *alg != '\0') {
		if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
			continue;
		TAILQ_FOREACH(k, &ssh->public_keys, next) {
			if (k->key->type == ktype ||
			    (sshkey_is_cert(k->key) && k->key->type ==
			    sshkey_type_plain(ktype))) {
				if (*replace != '\0')
					strlcat(replace, ",", maxlen);
				strlcat(replace, alg, maxlen);
				break;
			}
		}
	}
	if (*replace != '\0') {
		debug2("%s: orig/%d    %s", __func__, ssh->kex->server, orig);
		debug2("%s: replace/%d %s", __func__, ssh->kex->server, replace);
		free(orig);
		proposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = replace;
		replace = NULL;	/* owned by proposal */
		r = kex_prop2buf(ssh->kex->my, proposal);
	}
 out:
	free(oavail);
	free(replace);
	kex_prop_free(proposal);
	return r;
}

int
_ssh_host_key_sign(struct sshkey *privkey, struct sshkey *pubkey,
    u_char **signature, size_t *slen, const u_char *data, size_t dlen,
    const char *alg, u_int compat)
{
	return sshkey_sign(privkey, signature, slen, data, dlen, alg, compat);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: ssh_api.c,v 1.8 2017/04/30 23:13:25 djm Exp $ */
2			/*
3			* Copyright (c) 2012 Markus Friedl. All rights reserved.
4			*
5			* Permission to use, copy, modify, and distribute this software for any
6			* purpose with or without fee is hereby granted, provided that the above
7			* copyright notice and this permission notice appear in all copies.
8			*
9			* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16			*/
17
18			#include "ssh_api.h"
19			#include "compat.h"
20			#include "log.h"
21			#include "authfile.h"
22			#include "sshkey.h"
23			#include "misc.h"
24			#include "ssh2.h"
25			#include "version.h"
26			#include "myproposal.h"
27			#include "ssherr.h"
28			#include "sshbuf.h"
29
30			#include <string.h>
31
32			int _ssh_exchange_banner(struct ssh *);
33			int _ssh_send_banner(struct ssh , char *);
34			int _ssh_read_banner(struct ssh , char *);
35			int _ssh_order_hostkeyalgs(struct ssh *);
36			int _ssh_verify_host_key(struct sshkey , struct ssh );
37			struct sshkey _ssh_host_public_key(int, int, struct ssh );
38			struct sshkey _ssh_host_private_key(int, int, struct ssh );
39			int _ssh_host_key_sign(struct sshkey , struct sshkey ,
40			u_char *, size_t , const u_char , size_t, const char , u_int);
41
42			/*
43			* stubs for the server side implementation of kex.
44			* disable privsep so our stubs will never be called.
45			*/
46			int use_privsep = 0;
47			int mm_sshkey_sign(struct sshkey , u_char , u_int ,
48			u_char , u_int, char , u_int);
49			DH *mm_choose_dh(int, int, int);
50
51			/* Define these two variables here so that they are part of the library */
52			u_char *session_id2 = NULL;
53			u_int session_id2_len = 0;
54
55			int
56			mm_sshkey_sign(struct sshkey key, u_char sigp, u_int lenp,
57			u_char data, u_int datalen, char alg, u_int compat)
58			{
59			return (-1);
60			}
61
62			DH *
63			mm_choose_dh(int min, int nbits, int max)
64			{
65			return (NULL);
66			}
67
68			/* API */
69
70			int
71			ssh_init(struct ssh *sshp, int is_server, struct kex_params kex_params)
72			{
73			char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
74			struct ssh *ssh;
75			char **proposal;
76			static int called;
77			int r;
78
79			if (!called) {
80			OpenSSL_add_all_algorithms();
81			called = 1;
82			}
83
84			if ((ssh = ssh_packet_set_connection(NULL, -1, -1)) == NULL)
85			return SSH_ERR_ALLOC_FAIL;
86			if (is_server)
87			ssh_packet_set_server(ssh);
88
89			/* Initialize key exchange */
90			proposal = kex_params ? kex_params->proposal : myproposal;
91			if ((r = kex_new(ssh, proposal, &ssh->kex)) != 0) {
92			ssh_free(ssh);
93			return r;
94			}
95			ssh->kex->server = is_server;
96			if (is_server) {
97			#ifdef WITH_OPENSSL
98			ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
99			ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
100			ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
101			ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
102			ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
103			ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
104			ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
105			ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
106			#endif /* WITH_OPENSSL */
107			ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_server;
108			ssh->kex->load_host_public_key=&_ssh_host_public_key;
109			ssh->kex->load_host_private_key=&_ssh_host_private_key;
110			ssh->kex->sign=&_ssh_host_key_sign;
111			} else {
112			#ifdef WITH_OPENSSL
113			ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
114			ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
115			ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_client;
116			ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_client;
117			ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_client;
118			ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
119			ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
120			ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
121			#endif /* WITH_OPENSSL */
122			ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_client;
123			ssh->kex->verify_host_key =&_ssh_verify_host_key;
124			}
125			*sshp = ssh;
126			return 0;
127			}
128
129			void
130			ssh_free(struct ssh *ssh)
131			{
132			struct key_entry *k;
133
134			ssh_packet_close(ssh);
135			/*
136			* we've only created the public keys variants in case we
137			* are a acting as a server.
138			*/
139			while ((k = TAILQ_FIRST(&ssh->public_keys)) != NULL) {
140			TAILQ_REMOVE(&ssh->public_keys, k, next);
141			if (ssh->kex && ssh->kex->server)
142			sshkey_free(k->key);
143			free(k);
144			}
145			while ((k = TAILQ_FIRST(&ssh->private_keys)) != NULL) {
146			TAILQ_REMOVE(&ssh->private_keys, k, next);
147			free(k);
148			}
149			if (ssh->kex)
150			kex_free(ssh->kex);
151			free(ssh);
152			}
153
154			void
155			ssh_set_app_data(struct ssh ssh, void app_data)
156			{
157			ssh->app_data = app_data;
158			}
159
160			void *
161			ssh_get_app_data(struct ssh *ssh)
162			{
163			return ssh->app_data;
164			}
165
166			/* Returns < 0 on error, 0 otherwise */
167			int
168			ssh_add_hostkey(struct ssh ssh, struct sshkey key)
169			{
170			struct sshkey *pubkey = NULL;
171			struct key_entry k = NULL, k_prv = NULL;
172			int r;
173
174			if (ssh->kex->server) {
175			if ((r = sshkey_from_private(key, &pubkey)) != 0)
176			return r;
177			if ((k = malloc(sizeof(*k))) == NULL \|\|
178			(k_prv = malloc(sizeof(*k_prv))) == NULL) {
179			free(k);
180			sshkey_free(pubkey);
181			return SSH_ERR_ALLOC_FAIL;
182			}
183			k_prv->key = key;
184			TAILQ_INSERT_TAIL(&ssh->private_keys, k_prv, next);
185
186			/* add the public key, too */
187			k->key = pubkey;
188			TAILQ_INSERT_TAIL(&ssh->public_keys, k, next);
189			r = 0;
190			} else {
191			if ((k = malloc(sizeof(*k))) == NULL)
192			return SSH_ERR_ALLOC_FAIL;
193			k->key = key;
194			TAILQ_INSERT_TAIL(&ssh->public_keys, k, next);
195			r = 0;
196			}
197
198			return r;
199			}
200
201			int
202			ssh_set_verify_host_key_callback(struct ssh *ssh,
203			int (cb)(struct sshkey , struct ssh *))
204			{
205			if (cb == NULL \|\| ssh->kex == NULL)
206			return SSH_ERR_INVALID_ARGUMENT;
207
208			ssh->kex->verify_host_key = cb;
209
210			return 0;
211			}
212
213			int
214			ssh_input_append(struct ssh ssh, const u_char data, size_t len)
215			{
216			return sshbuf_put(ssh_packet_get_input(ssh), data, len);
217			}
218
219			int
220			ssh_packet_next(struct ssh ssh, u_char typep)
221			{
222			int r;
223			u_int32_t seqnr;
224			u_char type;
225
226			/*
227			* Try to read a packet. Return SSH_MSG_NONE if no packet or not
228			* enough data.
229			*/
230			*typep = SSH_MSG_NONE;
231			if (ssh->kex->client_version_string == NULL \|\|
232			ssh->kex->server_version_string == NULL)
233			return _ssh_exchange_banner(ssh);
234			/*
235			* If we enough data and a dispatch function then
236			* call the function and get the next packet.
237			* Otherwise return the packet type to the caller so it
238			* can decide how to go on.
239			*
240			* We will only call the dispatch function for:
241			* 20-29 Algorithm negotiation
242			* 30-49 Key exchange method specific (numbers can be reused for
243			* different authentication methods)
244			*/
245			for (;;) {
246			if ((r = ssh_packet_read_poll2(ssh, &type, &seqnr)) != 0)
247			return r;
248			if (type > 0 && type < DISPATCH_MAX &&
249			type >= SSH2_MSG_KEXINIT && type <= SSH2_MSG_TRANSPORT_MAX &&
250			ssh->dispatch[type] != NULL) {
251			if ((r = (*ssh->dispatch[type])(type, seqnr, ssh)) != 0)
252			return r;
253			} else {
254			*typep = type;
255			return 0;
256			}
257			}
258			}
259
260			const u_char *
261			ssh_packet_payload(struct ssh ssh, size_t lenp)
262			{
263			return sshpkt_ptr(ssh, lenp);
264			}
265
266			int
267			ssh_packet_put(struct ssh ssh, int type, const u_char data, size_t len)
268			{
269			int r;
270
271			if ((r = sshpkt_start(ssh, type)) != 0 \|\|
272			(r = sshpkt_put(ssh, data, len)) != 0 \|\|
273			(r = sshpkt_send(ssh)) != 0)
274			return r;
275			return 0;
276			}
277
278			const u_char *
279			ssh_output_ptr(struct ssh ssh, size_t len)
280			{
281			struct sshbuf *output = ssh_packet_get_output(ssh);
282
283			*len = sshbuf_len(output);
284			return sshbuf_ptr(output);
285			}
286
287			int
288			ssh_output_consume(struct ssh *ssh, size_t len)
289			{
290			return sshbuf_consume(ssh_packet_get_output(ssh), len);
291			}
292
293			int
294			ssh_output_space(struct ssh *ssh, size_t len)
295			{
296			return (0 == sshbuf_check_reserve(ssh_packet_get_output(ssh), len));
297			}
298
299			int
300			ssh_input_space(struct ssh *ssh, size_t len)
301			{
302			return (0 == sshbuf_check_reserve(ssh_packet_get_input(ssh), len));
303			}
304
305			/* Read other side's version identification. */
306			int
307			_ssh_read_banner(struct ssh ssh, char *bannerp)
308			{
309			struct sshbuf *input;
310			const char *s;
311			char buf[256], remote_version[256]; /* must be same size! */
312			const char *mismatch = "Protocol mismatch.\r\n";
313			int r, remote_major, remote_minor;
314			size_t i, n, j, len;
315
316			*bannerp = NULL;
317			input = ssh_packet_get_input(ssh);
318			len = sshbuf_len(input);
319			s = (const char *)sshbuf_ptr(input);
320			for (j = n = 0;;) {
321			for (i = 0; i < sizeof(buf) - 1; i++) {
322			if (j >= len)
323			return (0);
324			buf[i] = s[j++];
325			if (buf[i] == '\r') {
326			buf[i] = '\n';
327			buf[i + 1] = 0;
328			continue; /*XXX wait for \n /
329			}
330			if (buf[i] == '\n') {
331			buf[i + 1] = 0;
332			break;
333			}
334			}
335			buf[sizeof(buf) - 1] = 0;
336			if (strncmp(buf, "SSH-", 4) == 0)
337			break;
338			debug("ssh_exchange_identification: %s", buf);
339			if (ssh->kex->server \|\| ++n > 65536) {
340			if ((r = sshbuf_put(ssh_packet_get_output(ssh),
341			mismatch, strlen(mismatch))) != 0)
342			return r;
343			return SSH_ERR_NO_PROTOCOL_VERSION;
344			}
345			}
346			if ((r = sshbuf_consume(input, j)) != 0)
347			return r;
348
349			/*
350			* Check that the versions match. In future this might accept
351			* several versions and set appropriate flags to handle them.
352			*/
353			if (sscanf(buf, "SSH-%d.%d-%[^\n]\n",
354			&remote_major, &remote_minor, remote_version) != 3)
355			return SSH_ERR_INVALID_FORMAT;
356			debug("Remote protocol version %d.%d, remote software version %.100s",
357			remote_major, remote_minor, remote_version);
358
359			ssh->compat = compat_datafellows(remote_version);
360			if (remote_major == 1 && remote_minor == 99) {
361			remote_major = 2;
362			remote_minor = 0;
363			}
364			if (remote_major != 2)
365			return SSH_ERR_PROTOCOL_MISMATCH;
366			chop(buf);
367			debug("Remote version string %.100s", buf);
368			if ((*bannerp = strdup(buf)) == NULL)
369			return SSH_ERR_ALLOC_FAIL;
370			return 0;
371			}
372
373			/* Send our own protocol version identification. */
374			int
375			_ssh_send_banner(struct ssh ssh, char *bannerp)
376			{
377			char buf[256];
378			int r;
379
380			snprintf(buf, sizeof buf, "SSH-2.0-%.100s\r\n", SSH_VERSION);
381			if ((r = sshbuf_put(ssh_packet_get_output(ssh), buf, strlen(buf))) != 0)
382			return r;
383			chop(buf);
384			debug("Local version string %.100s", buf);
385			if ((*bannerp = strdup(buf)) == NULL)
386			return SSH_ERR_ALLOC_FAIL;
387			return 0;
388			}
389
390			int
391			_ssh_exchange_banner(struct ssh *ssh)
392			{
393			struct kex *kex = ssh->kex;
394			int r;
395
396			/*
397			* if _ssh_read_banner() cannot parse a full version string
398			* it will return NULL and we end up calling it again.
399			*/
400
401			r = 0;
402			if (kex->server) {
403			if (kex->server_version_string == NULL)
404			r = _ssh_send_banner(ssh, &kex->server_version_string);
405			if (r == 0 &&
406			kex->server_version_string != NULL &&
407			kex->client_version_string == NULL)
408			r = _ssh_read_banner(ssh, &kex->client_version_string);
409			} else {
410			if (kex->server_version_string == NULL)
411			r = _ssh_read_banner(ssh, &kex->server_version_string);
412			if (r == 0 &&
413			kex->server_version_string != NULL &&
414			kex->client_version_string == NULL)
415			r = _ssh_send_banner(ssh, &kex->client_version_string);
416			}
417			if (r != 0)
418			return r;
419			/* start initial kex as soon as we have exchanged the banners */
420			if (kex->server_version_string != NULL &&
421			kex->client_version_string != NULL) {
422			if ((r = _ssh_order_hostkeyalgs(ssh)) != 0 \|\|
423			(r = kex_send_kexinit(ssh)) != 0)
424			return r;
425			}
426			return 0;
427			}
428
429			struct sshkey *
430			_ssh_host_public_key(int type, int nid, struct ssh *ssh)
431			{
432			struct key_entry *k;
433
434			debug3("%s: need %d", __func__, type);
435			TAILQ_FOREACH(k, &ssh->public_keys, next) {
436			debug3("%s: check %s", __func__, sshkey_type(k->key));
437			if (k->key->type == type &&
438			(type != KEY_ECDSA \|\| k->key->ecdsa_nid == nid))
439			return (k->key);
440			}
441			return (NULL);
442			}
443
444			struct sshkey *
445			_ssh_host_private_key(int type, int nid, struct ssh *ssh)
446			{
447			struct key_entry *k;
448
449			debug3("%s: need %d", __func__, type);
450			TAILQ_FOREACH(k, &ssh->private_keys, next) {
451			debug3("%s: check %s", __func__, sshkey_type(k->key));
452			if (k->key->type == type &&
453			(type != KEY_ECDSA \|\| k->key->ecdsa_nid == nid))
454			return (k->key);
455			}
456			return (NULL);
457			}
458
459			int
460			_ssh_verify_host_key(struct sshkey hostkey, struct ssh ssh)
461			{
462			struct key_entry *k;
463
464			debug3("%s: need %s", __func__, sshkey_type(hostkey));
465			TAILQ_FOREACH(k, &ssh->public_keys, next) {
466			debug3("%s: check %s", __func__, sshkey_type(k->key));
467			if (sshkey_equal_public(hostkey, k->key))
468			return (0); /* ok */
469			}
470			return (-1); /* failed */
471			}
472
473			/* offer hostkey algorithms in kexinit depending on registered keys */
474			int
475			_ssh_order_hostkeyalgs(struct ssh *ssh)
476			{
477			struct key_entry *k;
478			char orig, avail, oavail = NULL, alg, *replace = NULL;
479			char **proposal;
480			size_t maxlen;
481			int ktype, r;
482
483			/* XXX we de-serialize ssh->kex->my, modify it, and change it */
484			if ((r = kex_buf2prop(ssh->kex->my, NULL, &proposal)) != 0)
485			return r;
486			orig = proposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
487			if ((oavail = avail = strdup(orig)) == NULL) {
488			r = SSH_ERR_ALLOC_FAIL;
489			goto out;
490			}
491			maxlen = strlen(avail) + 1;
492			if ((replace = calloc(1, maxlen)) == NULL) {
493			r = SSH_ERR_ALLOC_FAIL;
494			goto out;
495			}
496			*replace = '\0';
497			while ((alg = strsep(&avail, ",")) && *alg != '\0') {
498			if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
499			continue;
500			TAILQ_FOREACH(k, &ssh->public_keys, next) {
501			if (k->key->type == ktype \|\|
502			(sshkey_is_cert(k->key) && k->key->type ==
503			sshkey_type_plain(ktype))) {
504			if (*replace != '\0')
505			strlcat(replace, ",", maxlen);
506			strlcat(replace, alg, maxlen);
507			break;
508			}
509			}
510			}
511			if (*replace != '\0') {
512			debug2("%s: orig/%d %s", __func__, ssh->kex->server, orig);
513			debug2("%s: replace/%d %s", __func__, ssh->kex->server, replace);
514			free(orig);
515			proposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = replace;
516			replace = NULL; /* owned by proposal */
517			r = kex_prop2buf(ssh->kex->my, proposal);
518			}
519			out:
520			free(oavail);
521			free(replace);
522			kex_prop_free(proposal);
523			return r;
524			}
525
526			int
527			_ssh_host_key_sign(struct sshkey privkey, struct sshkey pubkey,
528			u_char *signature, size_t slen, const u_char *data, size_t dlen,
529			const char *alg, u_int compat)
530			{
531			return sshkey_sign(privkey, signature, slen, data, dlen, alg, compat);
532			}