OpenSolaris Launch

1 files changed, 1203 insertions, 0 deletions

diff --git a/usr/src/cmd/ssh/ssh-agent/ssh-agent.c b/usr/src/cmd/ssh/ssh-agent/ssh-agent.c
new file mode 100644
index 0000000000..ae398f9b8e
--- /dev/null
+++ b/usr/src/cmd/ssh/ssh-agent/ssh-agent.c
@@ -0,0 +1,1203 @@
+/*
+ * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * The authentication agent program.
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ *
+ * Copyright (c) 2000, 2001 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"
+#include "sys-queue.h"
+RCSID("$OpenBSD: ssh-agent.c,v 1.105 2002/10/01 20:34:12 markus Exp $");
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#ifdef HAVE_SOLARIS_PRIVILEGE
+#include <priv.h>
+#endif /* HAVE_SOLARIS_PRIVILEGE */
+
+#include <openssl/evp.h>
+#include <openssl/md5.h>
+
+#include "ssh.h"
+#include "rsa.h"
+#include "buffer.h"
+#include "bufaux.h"
+#include "xmalloc.h"
+#include "getput.h"
+#include "key.h"
+#include "authfd.h"
+#include "compat.h"
+#include "log.h"
+
+#ifdef SMARTCARD
+#include "scard.h"
+#endif
+
+typedef enum {
+	AUTH_UNUSED,
+	AUTH_SOCKET,
+	AUTH_CONNECTION
+} sock_type;
+
+typedef struct {
+	int fd;
+	sock_type type;
+	Buffer input;
+	Buffer output;
+	Buffer request;
+} SocketEntry;
+
+u_int sockets_alloc = 0;
+SocketEntry *sockets = NULL;
+
+typedef struct identity {
+	TAILQ_ENTRY(identity) next;
+	Key *key;
+	char *comment;
+	u_int death;
+} Identity;
+
+typedef struct {
+	int nentries;
+	TAILQ_HEAD(idqueue, identity) idlist;
+} Idtab;
+
+/* private key table, one per protocol version */
+Idtab idtable[3];
+
+int max_fd = 0;
+
+/* pid of shell == parent of agent */
+pid_t parent_pid = -1;
+
+/* pathname and directory for AUTH_SOCKET */
+char socket_name[1024];
+char socket_dir[1024];
+
+/* locking */
+int locked = 0;
+char *lock_passwd = NULL;
+
+#ifdef HAVE___PROGNAME
+extern char *__progname;
+#else
+char *__progname;
+#endif
+
+static void
+close_socket(SocketEntry *e)
+{
+	close(e->fd);
+	e->fd = -1;
+	e->type = AUTH_UNUSED;
+	buffer_free(&e->input);
+	buffer_free(&e->output);
+	buffer_free(&e->request);
+}
+
+static void
+idtab_init(void)
+{
+	int i;
+
+	for (i = 0; i <=2; i++) {
+		TAILQ_INIT(&idtable[i].idlist);
+		idtable[i].nentries = 0;
+	}
+}
+
+/* return private key table for requested protocol version */
+static Idtab *
+idtab_lookup(int version)
+{
+	if (version < 1 || version > 2)
+		fatal("internal error, bad protocol version %d", version);
+	return &idtable[version];
+}
+
+static void
+free_identity(Identity *id)
+{
+	key_free(id->key);
+	xfree(id->comment);
+	xfree(id);
+}
+
+/* return matching private key for given public key */
+static Identity *
+lookup_identity(Key *key, int version)
+{
+	Identity *id;
+
+	Idtab *tab = idtab_lookup(version);
+	TAILQ_FOREACH(id, &tab->idlist, next) {
+		if (key_equal(key, id->key))
+			return (id);
+	}
+	return (NULL);
+}
+
+/* send list of supported public keys to 'client' */
+static void
+process_request_identities(SocketEntry *e, int version)
+{
+	Idtab *tab = idtab_lookup(version);
+	Identity *id;
+	Buffer msg;
+
+	buffer_init(&msg);
+	buffer_put_char(&msg, (version == 1) ?
+	    SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
+	buffer_put_int(&msg, tab->nentries);
+	TAILQ_FOREACH(id, &tab->idlist, next) {
+		if (id->key->type == KEY_RSA1) {
+			buffer_put_int(&msg, BN_num_bits(id->key->rsa->n));
+			buffer_put_bignum(&msg, id->key->rsa->e);
+			buffer_put_bignum(&msg, id->key->rsa->n);
+		} else {
+			u_char *blob;
+			u_int blen;
+			key_to_blob(id->key, &blob, &blen);
+			buffer_put_string(&msg, blob, blen);
+			xfree(blob);
+		}
+		buffer_put_cstring(&msg, id->comment);
+	}
+	buffer_put_int(&e->output, buffer_len(&msg));
+	buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
+	buffer_free(&msg);
+}
+
+/* ssh1 only */
+static void
+process_authentication_challenge1(SocketEntry *e)
+{
+	u_char buf[32], mdbuf[16], session_id[16];
+	u_int response_type;
+	BIGNUM *challenge;
+	Identity *id;
+	int i, len;
+	Buffer msg;
+	MD5_CTX md;
+	Key *key;
+
+	buffer_init(&msg);
+	key = key_new(KEY_RSA1);
+	if ((challenge = BN_new()) == NULL)
+		fatal("process_authentication_challenge1: BN_new failed");
+
+	(void) buffer_get_int(&e->request);			/* ignored */
+	buffer_get_bignum(&e->request, key->rsa->e);
+	buffer_get_bignum(&e->request, key->rsa->n);
+	buffer_get_bignum(&e->request, challenge);
+
+	/* Only protocol 1.1 is supported */
+	if (buffer_len(&e->request) == 0)
+		goto failure;
+	buffer_get(&e->request, session_id, 16);
+	response_type = buffer_get_int(&e->request);
+	if (response_type != 1)
+		goto failure;
+
+	id = lookup_identity(key, 1);
+	if (id != NULL) {
+		Key *private = id->key;
+		/* Decrypt the challenge using the private key. */
+		if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
+			goto failure;
+
+		/* The response is MD5 of decrypted challenge plus session id. */
+		len = BN_num_bytes(challenge);
+		if (len <= 0 || len > 32) {
+			log("process_authentication_challenge: bad challenge length %d", len);
+			goto failure;
+		}
+		memset(buf, 0, 32);
+		BN_bn2bin(challenge, buf + 32 - len);
+		MD5_Init(&md);
+		MD5_Update(&md, buf, 32);
+		MD5_Update(&md, session_id, 16);
+		MD5_Final(mdbuf, &md);
+
+		/* Send the response. */
+		buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
+		for (i = 0; i < 16; i++)
+			buffer_put_char(&msg, mdbuf[i]);
+		goto send;
+	}
+
+failure:
+	/* Unknown identity or protocol error.  Send failure. */
+	buffer_put_char(&msg, SSH_AGENT_FAILURE);
+send:
+	buffer_put_int(&e->output, buffer_len(&msg));
+	buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
+	key_free(key);
+	BN_clear_free(challenge);
+	buffer_free(&msg);
+}
+
+/* ssh2 only */
+static void
+process_sign_request2(SocketEntry *e)
+{
+	u_char *blob, *data, *signature = NULL;
+	u_int blen, dlen, slen = 0;
+	extern int datafellows;
+	int ok = -1, flags;
+	Buffer msg;
+	Key *key;
+
+	datafellows = 0;
+
+	blob = buffer_get_string(&e->request, &blen);
+	data = buffer_get_string(&e->request, &dlen);
+
+	flags = buffer_get_int(&e->request);
+	if (flags & SSH_AGENT_OLD_SIGNATURE)
+		datafellows = SSH_BUG_SIGBLOB;
+
+	key = key_from_blob(blob, blen);
+	if (key != NULL) {
+		Identity *id = lookup_identity(key, 2);
+		if (id != NULL)
+			ok = key_sign(id->key, &signature, &slen, data, dlen);
+	}
+	key_free(key);
+	buffer_init(&msg);
+	if (ok == 0) {
+		buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
+		buffer_put_string(&msg, signature, slen);
+	} else {
+		buffer_put_char(&msg, SSH_AGENT_FAILURE);
+	}
+	buffer_put_int(&e->output, buffer_len(&msg));
+	buffer_append(&e->output, buffer_ptr(&msg),
+	    buffer_len(&msg));
+	buffer_free(&msg);
+	xfree(data);
+	xfree(blob);
+	if (signature != NULL)
+		xfree(signature);
+}
+
+/* shared */
+static void
+process_remove_identity(SocketEntry *e, int version)
+{
+	u_int blen, bits;
+	int success = 0;
+	Key *key = NULL;
+	u_char *blob;
+
+	switch (version) {
+	case 1:
+		key = key_new(KEY_RSA1);
+		bits = buffer_get_int(&e->request);
+		buffer_get_bignum(&e->request, key->rsa->e);
+		buffer_get_bignum(&e->request, key->rsa->n);
+
+		if (bits != key_size(key))
+			log("Warning: identity keysize mismatch: actual %u, announced %u",
+			    key_size(key), bits);
+		break;
+	case 2:
+		blob = buffer_get_string(&e->request, &blen);
+		key = key_from_blob(blob, blen);
+		xfree(blob);
+		break;
+	}
+	if (key != NULL) {
+		Identity *id = lookup_identity(key, version);
+		if (id != NULL) {
+			/*
+			 * We have this key.  Free the old key.  Since we
+			 * don\'t want to leave empty slots in the middle of
+			 * the array, we actually free the key there and move
+			 * all the entries between the empty slot and the end
+			 * of the array.
+			 */
+			Idtab *tab = idtab_lookup(version);
+			if (tab->nentries < 1)
+				fatal("process_remove_identity: "
+				    "internal error: tab->nentries %d",
+				    tab->nentries);
+			TAILQ_REMOVE(&tab->idlist, id, next);
+			free_identity(id);
+			tab->nentries--;
+			success = 1;
+		}
+		key_free(key);
+	}
+	buffer_put_int(&e->output, 1);
+	buffer_put_char(&e->output,
+	    success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
+}
+
+static void
+process_remove_all_identities(SocketEntry *e, int version)
+{
+	Idtab *tab = idtab_lookup(version);
+	Identity *id;
+
+	/* Loop over all identities and clear the keys. */
+	for (id = TAILQ_FIRST(&tab->idlist); id;
+	    id = TAILQ_FIRST(&tab->idlist)) {
+		TAILQ_REMOVE(&tab->idlist, id, next);
+		free_identity(id);
+	}
+
+	/* Mark that there are no identities. */
+	tab->nentries = 0;
+
+	/* Send success. */
+	buffer_put_int(&e->output, 1);
+	buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
+}
+
+static void
+reaper(void)
+{
+	u_int now = time(NULL);
+	Identity *id, *nxt;
+	int version;
+	Idtab *tab;
+
+	for (version = 1; version < 3; version++) {
+		tab = idtab_lookup(version);
+		for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
+			nxt = TAILQ_NEXT(id, next);
+			if (id->death != 0 && now >= id->death) {
+				TAILQ_REMOVE(&tab->idlist, id, next);
+				free_identity(id);
+				tab->nentries--;
+			}
+		}
+	}
+}
+
+static void
+process_add_identity(SocketEntry *e, int version)
+{
+	Idtab *tab = idtab_lookup(version);
+	int type, success = 0, death = 0;
+	char *type_name, *comment;
+	Key *k = NULL;
+
+	switch (version) {
+	case 1:
+		k = key_new_private(KEY_RSA1);
+		(void) buffer_get_int(&e->request);		/* ignored */
+		buffer_get_bignum(&e->request, k->rsa->n);
+		buffer_get_bignum(&e->request, k->rsa->e);
+		buffer_get_bignum(&e->request, k->rsa->d);
+		buffer_get_bignum(&e->request, k->rsa->iqmp);
+
+		/* SSH and SSL have p and q swapped */
+		buffer_get_bignum(&e->request, k->rsa->q);	/* p */
+		buffer_get_bignum(&e->request, k->rsa->p);	/* q */
+
+		/* Generate additional parameters */
+		rsa_generate_additional_parameters(k->rsa);
+		break;
+	case 2:
+		type_name = buffer_get_string(&e->request, NULL);
+		type = key_type_from_name(type_name);
+		xfree(type_name);
+		switch (type) {
+		case KEY_DSA:
+			k = key_new_private(type);
+			buffer_get_bignum2(&e->request, k->dsa->p);
+			buffer_get_bignum2(&e->request, k->dsa->q);
+			buffer_get_bignum2(&e->request, k->dsa->g);
+			buffer_get_bignum2(&e->request, k->dsa->pub_key);
+			buffer_get_bignum2(&e->request, k->dsa->priv_key);
+			break;
+		case KEY_RSA:
+			k = key_new_private(type);
+			buffer_get_bignum2(&e->request, k->rsa->n);
+			buffer_get_bignum2(&e->request, k->rsa->e);
+			buffer_get_bignum2(&e->request, k->rsa->d);
+			buffer_get_bignum2(&e->request, k->rsa->iqmp);
+			buffer_get_bignum2(&e->request, k->rsa->p);
+			buffer_get_bignum2(&e->request, k->rsa->q);
+
+			/* Generate additional parameters */
+			rsa_generate_additional_parameters(k->rsa);
+			break;
+		default:
+			buffer_clear(&e->request);
+			goto send;
+		}
+		break;
+	}
+	comment = buffer_get_string(&e->request, NULL);
+	if (k == NULL) {
+		xfree(comment);
+		goto send;
+	}
+	success = 1;
+	while (buffer_len(&e->request)) {
+		switch (buffer_get_char(&e->request)) {
+		case SSH_AGENT_CONSTRAIN_LIFETIME:
+			death = time(NULL) + buffer_get_int(&e->request);
+			break;
+		default:
+			break;
+		}
+	}
+	if (lookup_identity(k, version) == NULL) {
+		Identity *id = xmalloc(sizeof(Identity));
+		id->key = k;
+		id->comment = comment;
+		id->death = death;
+		TAILQ_INSERT_TAIL(&tab->idlist, id, next);
+		/* Increment the number of identities. */
+		tab->nentries++;
+	} else {
+		key_free(k);
+		xfree(comment);
+	}
+send:
+	buffer_put_int(&e->output, 1);
+	buffer_put_char(&e->output,
+	    success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
+}
+
+/* XXX todo: encrypt sensitive data with passphrase */
+static void
+process_lock_agent(SocketEntry *e, int lock)
+{
+	int success = 0;
+	char *passwd;
+
+	passwd = buffer_get_string(&e->request, NULL);
+	if (locked && !lock && strcmp(passwd, lock_passwd) == 0) {
+		locked = 0;
+		memset(lock_passwd, 0, strlen(lock_passwd));
+		xfree(lock_passwd);
+		lock_passwd = NULL;
+		success = 1;
+	} else if (!locked && lock) {
+		locked = 1;
+		lock_passwd = xstrdup(passwd);
+		success = 1;
+	}
+	memset(passwd, 0, strlen(passwd));
+	xfree(passwd);
+
+	buffer_put_int(&e->output, 1);
+	buffer_put_char(&e->output,
+	    success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
+}
+
+static void
+no_identities(SocketEntry *e, u_int type)
+{
+	Buffer msg;
+
+	buffer_init(&msg);
+	buffer_put_char(&msg,
+	    (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
+	    SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
+	buffer_put_int(&msg, 0);
+	buffer_put_int(&e->output, buffer_len(&msg));
+	buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
+	buffer_free(&msg);
+}
+
+#ifdef SMARTCARD
+static void
+process_add_smartcard_key (SocketEntry *e)
+{
+	char *sc_reader_id = NULL, *pin;
+	int i, version, success = 0;
+	Key **keys, *k;
+	Identity *id;
+	Idtab *tab;
+
+	sc_reader_id = buffer_get_string(&e->request, NULL);
+	pin = buffer_get_string(&e->request, NULL);
+	keys = sc_get_keys(sc_reader_id, pin);
+	xfree(sc_reader_id);
+	xfree(pin);
+
+	if (keys == NULL || keys[0] == NULL) {
+		error("sc_get_keys failed");
+		goto send;
+	}
+	for (i = 0; keys[i] != NULL; i++) {
+		k = keys[i];
+		version = k->type == KEY_RSA1 ? 1 : 2;
+		tab = idtab_lookup(version);
+		if (lookup_identity(k, version) == NULL) {
+			id = xmalloc(sizeof(Identity));
+			id->key = k;
+			id->comment = xstrdup("smartcard key");
+			id->death = 0;
+			TAILQ_INSERT_TAIL(&tab->idlist, id, next);
+			tab->nentries++;
+			success = 1;
+		} else {
+			key_free(k);
+		}
+		keys[i] = NULL;
+	}
+	xfree(keys);
+send:
+	buffer_put_int(&e->output, 1);
+	buffer_put_char(&e->output,
+	    success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
+}
+
+static void
+process_remove_smartcard_key(SocketEntry *e)
+{
+	char *sc_reader_id = NULL, *pin;
+	int i, version, success = 0;
+	Key **keys, *k = NULL;
+	Identity *id;
+	Idtab *tab;
+
+	sc_reader_id = buffer_get_string(&e->request, NULL);
+	pin = buffer_get_string(&e->request, NULL);
+	keys = sc_get_keys(sc_reader_id, pin);
+	xfree(sc_reader_id);
+	xfree(pin);
+
+	if (keys == NULL || keys[0] == NULL) {
+		error("sc_get_keys failed");
+		goto send;
+	}
+	for (i = 0; keys[i] != NULL; i++) {
+		k = keys[i];
+		version = k->type == KEY_RSA1 ? 1 : 2;
+		if ((id = lookup_identity(k, version)) != NULL) {
+			tab = idtab_lookup(version);
+			TAILQ_REMOVE(&tab->idlist, id, next);
+			tab->nentries--;
+			free_identity(id);
+			success = 1;
+		}
+		key_free(k);
+		keys[i] = NULL;
+	}
+	xfree(keys);
+send:
+	buffer_put_int(&e->output, 1);
+	buffer_put_char(&e->output,
+	    success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
+}
+#endif /* SMARTCARD */
+
+/* dispatch incoming messages */
+
+static void
+process_message(SocketEntry *e)
+{
+	u_int msg_len, type;
+	u_char *cp;
+
+	/* kill dead keys */
+	reaper();
+
+	if (buffer_len(&e->input) < 5)
+		return;		/* Incomplete message. */
+	cp = buffer_ptr(&e->input);
+	msg_len = GET_32BIT(cp);
+	if (msg_len > 256 * 1024) {
+		close_socket(e);
+		return;
+	}
+	if (buffer_len(&e->input) < msg_len + 4)
+		return;
+
+	/* move the current input to e->request */
+	buffer_consume(&e->input, 4);
+	buffer_clear(&e->request);
+	buffer_append(&e->request, buffer_ptr(&e->input), msg_len);
+	buffer_consume(&e->input, msg_len);
+	type = buffer_get_char(&e->request);
+
+	/* check wheter agent is locked */
+	if (locked && type != SSH_AGENTC_UNLOCK) {
+		buffer_clear(&e->request);
+		switch (type) {
+		case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
+		case SSH2_AGENTC_REQUEST_IDENTITIES:
+			/* send empty lists */
+			no_identities(e, type);
+			break;
+		default:
+			/* send a fail message for all other request types */
+			buffer_put_int(&e->output, 1);
+			buffer_put_char(&e->output, SSH_AGENT_FAILURE);
+		}
+		return;
+	}
+
+	debug("type %d", type);
+	switch (type) {
+	case SSH_AGENTC_LOCK:
+	case SSH_AGENTC_UNLOCK:
+		process_lock_agent(e, type == SSH_AGENTC_LOCK);
+		break;
+	/* ssh1 */
+	case SSH_AGENTC_RSA_CHALLENGE:
+		process_authentication_challenge1(e);
+		break;
+	case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
+		process_request_identities(e, 1);
+		break;
+	case SSH_AGENTC_ADD_RSA_IDENTITY:
+	case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED:
+		process_add_identity(e, 1);
+		break;
+	case SSH_AGENTC_REMOVE_RSA_IDENTITY:
+		process_remove_identity(e, 1);
+		break;
+	case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
+		process_remove_all_identities(e, 1);
+		break;
+	/* ssh2 */
+	case SSH2_AGENTC_SIGN_REQUEST:
+		process_sign_request2(e);
+		break;
+	case SSH2_AGENTC_REQUEST_IDENTITIES:
+		process_request_identities(e, 2);
+		break;
+	case SSH2_AGENTC_ADD_IDENTITY:
+	case SSH2_AGENTC_ADD_ID_CONSTRAINED:
+		process_add_identity(e, 2);
+		break;
+	case SSH2_AGENTC_REMOVE_IDENTITY:
+		process_remove_identity(e, 2);
+		break;
+	case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
+		process_remove_all_identities(e, 2);
+		break;
+#ifdef SMARTCARD
+	case SSH_AGENTC_ADD_SMARTCARD_KEY:
+		process_add_smartcard_key(e);
+		break;
+	case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
+		process_remove_smartcard_key(e);
+		break;
+#endif /* SMARTCARD */
+	default:
+		/* Unknown message.  Respond with failure. */
+		error("Unknown message %d", type);
+		buffer_clear(&e->request);
+		buffer_put_int(&e->output, 1);
+		buffer_put_char(&e->output, SSH_AGENT_FAILURE);
+		break;
+	}
+}
+
+static void
+new_socket(sock_type type, int fd)
+{
+	u_int i, old_alloc;
+
+	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
+		error("fcntl O_NONBLOCK: %s", strerror(errno));
+
+	if (fd > max_fd)
+		max_fd = fd;
+
+	for (i = 0; i < sockets_alloc; i++)
+		if (sockets[i].type == AUTH_UNUSED) {
+			sockets[i].fd = fd;
+			sockets[i].type = type;
+			buffer_init(&sockets[i].input);
+			buffer_init(&sockets[i].output);
+			buffer_init(&sockets[i].request);
+			return;
+		}
+	old_alloc = sockets_alloc;
+	sockets_alloc += 10;
+	if (sockets)
+		sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
+	else
+		sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
+	for (i = old_alloc; i < sockets_alloc; i++)
+		sockets[i].type = AUTH_UNUSED;
+	sockets[old_alloc].type = type;
+	sockets[old_alloc].fd = fd;
+	buffer_init(&sockets[old_alloc].input);
+	buffer_init(&sockets[old_alloc].output);
+	buffer_init(&sockets[old_alloc].request);
+}
+
+static int
+prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
+{
+	u_int i, sz;
+	int n = 0;
+
+	for (i = 0; i < sockets_alloc; i++) {
+		switch (sockets[i].type) {
+		case AUTH_SOCKET:
+		case AUTH_CONNECTION:
+			n = MAX(n, sockets[i].fd);
+			break;
+		case AUTH_UNUSED:
+			break;
+		default:
+			fatal("Unknown socket type %d", sockets[i].type);
+			break;
+		}
+	}
+
+	sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
+	if (*fdrp == NULL || sz > *nallocp) {
+		if (*fdrp)
+			xfree(*fdrp);
+		if (*fdwp)
+			xfree(*fdwp);
+		*fdrp = xmalloc(sz);
+		*fdwp = xmalloc(sz);
+		*nallocp = sz;
+	}
+	if (n < *fdl)
+		debug("XXX shrink: %d < %d", n, *fdl);
+	*fdl = n;
+	memset(*fdrp, 0, sz);
+	memset(*fdwp, 0, sz);
+
+	for (i = 0; i < sockets_alloc; i++) {
+		switch (sockets[i].type) {
+		case AUTH_SOCKET:
+		case AUTH_CONNECTION:
+			FD_SET(sockets[i].fd, *fdrp);
+			if (buffer_len(&sockets[i].output) > 0)
+				FD_SET(sockets[i].fd, *fdwp);
+			break;
+		default:
+			break;
+		}
+	}
+	return (1);
+}
+
+static void
+after_select(fd_set *readset, fd_set *writeset)
+{
+	struct sockaddr_un sunaddr;
+	socklen_t slen;
+	char buf[1024];
+	int len, sock;
+	u_int i;
+	uid_t euid;
+	gid_t egid;
+
+	for (i = 0; i < sockets_alloc; i++)
+		switch (sockets[i].type) {
+		case AUTH_UNUSED:
+			break;
+		case AUTH_SOCKET:
+			if (FD_ISSET(sockets[i].fd, readset)) {
+				slen = sizeof(sunaddr);
+				sock = accept(sockets[i].fd,
+				    (struct sockaddr *) &sunaddr, &slen);
+				if (sock < 0) {
+					error("accept from AUTH_SOCKET: %s",
+					    strerror(errno));
+					break;
+				}
+				if (getpeereid(sock, &euid, &egid) < 0) {
+					error("getpeereid %d failed: %s",
+					    sock, strerror(errno));
+					close(sock);
+					break;
+				}
+				if ((euid != 0) && (getuid() != euid)) {
+					error("uid mismatch: "
+					    "peer euid %u != uid %u",
+					    (u_int) euid, (u_int) getuid());
+					close(sock);
+					break;
+				}
+				new_socket(AUTH_CONNECTION, sock);
+			}
+			break;
+		case AUTH_CONNECTION:
+			if (buffer_len(&sockets[i].output) > 0 &&
+			    FD_ISSET(sockets[i].fd, writeset)) {
+				do {
+					len = write(sockets[i].fd,
+					    buffer_ptr(&sockets[i].output),
+					    buffer_len(&sockets[i].output));
+					if (len == -1 && (errno == EAGAIN ||
+					    errno == EINTR))
+						continue;
+					break;
+				} while (1);
+				if (len <= 0) {
+					close_socket(&sockets[i]);
+					break;
+				}
+				buffer_consume(&sockets[i].output, len);
+			}
+			if (FD_ISSET(sockets[i].fd, readset)) {
+				do {
+					len = read(sockets[i].fd, buf, sizeof(buf));
+					if (len == -1 && (errno == EAGAIN ||
+					    errno == EINTR))
+						continue;
+					break;
+				} while (1);
+				if (len <= 0) {
+					close_socket(&sockets[i]);
+					break;
+				}
+				buffer_append(&sockets[i].input, buf, len);
+				process_message(&sockets[i]);
+			}
+			break;
+		default:
+			fatal("Unknown type %d", sockets[i].type);
+		}
+}
+
+static void
+cleanup_socket(void *p)
+{
+	if (socket_name[0])
+		unlink(socket_name);
+	if (socket_dir[0])
+		rmdir(socket_dir);
+}
+
+static void
+cleanup_exit(int i)
+{
+	cleanup_socket(NULL);
+	exit(i);
+}
+
+static void
+cleanup_handler(int sig)
+{
+	cleanup_socket(NULL);
+	_exit(2);
+}
+
+static void
+check_parent_exists(int sig)
+{
+	int save_errno = errno;
+
+	if (parent_pid != -1 && getppid() != parent_pid) {
+		/* printf("Parent has died - Authentication agent exiting.\n"); */
+		cleanup_handler(sig); /* safe */
+	}
+	signal(SIGALRM, check_parent_exists);
+	alarm(10);
+	errno = save_errno;
+}
+
+static void
+usage(void)
+{
+	fprintf(stderr,
+		gettext("Usage: %s [options] [command [args ...]]\n"
+		    "Options:\n"
+		    "  -c          Generate C-shell commands on stdout.\n"
+		    "  -s          Generate Bourne shell commands on stdout.\n"
+		    "  -k          Kill the current agent.\n"
+		    "  -d          Debug mode.\n"
+		    "  -a socket   Bind agent socket to given name.\n"),
+		__progname);
+	exit(1);
+}
+
+int
+main(int ac, char **av)
+{
+	int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
+	char *shell, *pidstr, *agentsocket = NULL;
+	const char *format;
+	fd_set *readsetp = NULL, *writesetp = NULL;
+	struct sockaddr_un sunaddr;
+#ifdef HAVE_SETRLIMIT
+	struct rlimit rlim;
+#endif
+#ifdef HAVE_CYGWIN
+	int prev_mask;
+#endif
+	extern int optind;
+	extern char *optarg;
+	pid_t pid;
+	char pidstrbuf[1 + 3 * sizeof pid];
+#ifdef HAVE_SOLARIS_PRIVILEGE
+	priv_set_t *myprivs;
+#endif /* HAVE_SOLARIS_PRIVILEGE */
+
+	/* drop */
+	setegid(getgid());
+	setgid(getgid());
+
+	(void) g11n_setlocale(LC_ALL, "");
+
+	SSLeay_add_all_algorithms();
+
+	__progname = get_progname(av[0]);
+	init_rng();
+	seed_rng();
+
+	while ((ch = getopt(ac, av, "cdksa:")) != -1) {
+		switch (ch) {
+		case 'c':
+			if (s_flag)
+				usage();
+			c_flag++;
+			break;
+		case 'k':
+			k_flag++;
+			break;
+		case 's':
+			if (c_flag)
+				usage();
+			s_flag++;
+			break;
+		case 'd':
+			if (d_flag)
+				usage();
+			d_flag++;
+			break;
+		case 'a':
+			agentsocket = optarg;
+			break;
+		default:
+			usage();
+		}
+	}
+	ac -= optind;
+	av += optind;
+
+	if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
+		usage();
+
+	if (ac == 0 && !c_flag && !s_flag) {
+		shell = getenv("SHELL");
+		if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
+			c_flag = 1;
+	}
+	if (k_flag) {
+		pidstr = getenv(SSH_AGENTPID_ENV_NAME);
+		if (pidstr == NULL) {
+			fprintf(stderr,
+				gettext("%s not set, cannot kill agent\n"),
+				SSH_AGENTPID_ENV_NAME);
+			exit(1);
+		}
+		pid = atoi(pidstr);
+		if (pid < 1) {
+			fprintf(stderr,
+			    gettext("%s=\")%s\", which is not a good PID\n"),
+			    SSH_AGENTPID_ENV_NAME, pidstr);
+			exit(1);
+		}
+		if (kill(pid, SIGTERM) == -1) {
+			perror("kill");
+			exit(1);
+		}
+		format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
+		printf(format, SSH_AUTHSOCKET_ENV_NAME);
+		printf(format, SSH_AGENTPID_ENV_NAME);
+		printf("echo ");
+		printf(gettext("Agent pid %ld killed;\n"), (long)pid);
+		exit(0);
+	}
+	parent_pid = getpid();
+
+	if (agentsocket == NULL) {
+		/* Create private directory for agent socket */
+		strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
+		if (mkdtemp(socket_dir) == NULL) {
+			perror("mkdtemp: private socket dir");
+			exit(1);
+		}
+		snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
+		    (long)parent_pid);
+	} else {
+		/* Try to use specified agent socket */
+		socket_dir[0] = '\0';
+		strlcpy(socket_name, agentsocket, sizeof socket_name);
+	}
+
+	/*
+	 * Create socket early so it will exist before command gets run from
+	 * the parent.
+	 */
+	sock = socket(AF_UNIX, SOCK_STREAM, 0);
+	if (sock < 0) {
+		perror("socket");
+		cleanup_exit(1);
+	}
+	memset(&sunaddr, 0, sizeof(sunaddr));
+	sunaddr.sun_family = AF_UNIX;
+	strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
+#ifdef HAVE_CYGWIN
+	prev_mask = umask(0177);
+#endif
+	if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
+		perror("bind");
+#ifdef HAVE_CYGWIN
+		umask(prev_mask);
+#endif
+		cleanup_exit(1);
+	}
+#ifdef HAVE_CYGWIN
+	umask(prev_mask);
+#endif
+	if (listen(sock, 128) < 0) {
+		perror("listen");
+		cleanup_exit(1);
+	}
+
+	/*
+	 * Fork, and have the parent execute the command, if any, or present
+	 * the socket data.  The child continues as the authentication agent.
+	 */
+	if (d_flag) {
+		log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
+		format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
+		printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
+		    SSH_AUTHSOCKET_ENV_NAME);
+		printf("echo ");
+		printf(gettext("Agent pid %ld;\n"), (long)parent_pid);
+		goto skip;
+	}
+	pid = fork();
+	if (pid == -1) {
+		perror("fork");
+		cleanup_exit(1);
+	}
+	if (pid != 0) {		/* Parent - execute the given command. */
+		close(sock);
+		snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
+		if (ac == 0) {
+			format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
+			printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
+			    SSH_AUTHSOCKET_ENV_NAME);
+			printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
+			    SSH_AGENTPID_ENV_NAME);
+			printf("echo ");
+			printf(gettext("Agent pid %ld;\n"), (long)pid);
+			exit(0);
+		}
+		if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
+		    setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
+			perror("setenv");
+			exit(1);
+		}
+		execvp(av[0], av);
+		perror(av[0]);
+		exit(1);
+	}
+	/* child */
+	log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
+
+#ifdef HAVE_SOLARIS_PRIVILEGE
+	/*
+	 * Drop unneeded privs, including basic ones like fork/exec.
+	 *
+	 * Idiom: remove from 'basic' privs we know we don't want,
+	 * invert the result and remove the resulting set from P.
+	 *
+	 * None of the priv_delset() calls below, nor the setppriv call
+	 * below can fail, so their return values are not checked.
+	 */
+	if ((myprivs = priv_str_to_set("basic", ",", NULL)) == NULL)
+		fatal("priv_str_to_set failed: %m");
+	(void) priv_delset(myprivs, PRIV_PROC_EXEC);
+	(void) priv_delset(myprivs, PRIV_PROC_FORK);
+	(void) priv_delset(myprivs, PRIV_FILE_LINK_ANY);
+	(void) priv_delset(myprivs, PRIV_PROC_INFO);
+	(void) priv_delset(myprivs, PRIV_PROC_SESSION);
+	priv_inverse(myprivs);
+	(void) setppriv(PRIV_OFF, PRIV_PERMITTED, myprivs);
+	(void) priv_freeset(myprivs);
+#endif /* HAVE_SOLARIS_PRIVILEGE */
+
+	if (setsid() == -1) {
+		error("setsid: %s", strerror(errno));
+		cleanup_exit(1);
+	}
+
+	(void)chdir("/");
+	close(0);
+	close(1);
+	close(2);
+
+#ifdef HAVE_SETRLIMIT
+	/* deny core dumps, since memory contains unencrypted private keys */
+	rlim.rlim_cur = rlim.rlim_max = 0;
+	if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
+		error("setrlimit RLIMIT_CORE: %s", strerror(errno));
+		cleanup_exit(1);
+	}
+#endif
+
+skip:
+	fatal_add_cleanup(cleanup_socket, NULL);
+	new_socket(AUTH_SOCKET, sock);
+	if (ac > 0) {
+		signal(SIGALRM, check_parent_exists);
+		alarm(10);
+	}
+	idtab_init();
+	if (!d_flag)
+		signal(SIGINT, SIG_IGN);
+	signal(SIGPIPE, SIG_IGN);
+	signal(SIGHUP, cleanup_handler);
+	signal(SIGTERM, cleanup_handler);
+	nalloc = 0;
+
+	while (1) {
+		prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
+		if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
+			if (errno == EINTR)
+				continue;
+			fatal("select: %s", strerror(errno));
+		}
+		after_select(readsetp, writesetp);
+	}
+	/* NOTREACHED */
+	return (0);	/* keep lint happy */
+}