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ssh-agent.c
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/* $OpenBSD: ssh-agent.c,v 1.171 2010/11/21 01:01:13 djm Exp $ */
/*
* Author: Tatu Ylonen <[email protected]>
* Copyright (c) 1995 Tatu Ylonen <[email protected]>, 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/types.h>
#include <sys/param.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/socket.h>
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
#endif
#ifdef HAVE_SYS_UN_H
# include <sys/un.h>
#endif
#include "openbsd-compat/sys-queue.h"
#include <openssl/evp.h>
#include <openssl/md5.h>
#include "openbsd-compat/openssl-compat.h"
#include <errno.h>
#include <fcntl.h>
#ifdef HAVE_PATHS_H
# include <paths.h>
#endif
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <unistd.h>
#include "xmalloc.h"
#include "ssh.h"
#include "rsa.h"
#include "buffer.h"
#include "key.h"
#include "authfd.h"
#include "compat.h"
#include "log.h"
#include "misc.h"
#ifdef ENABLE_PKCS11
#include "ssh-pkcs11.h"
#endif
#if defined(HAVE_SYS_PRCTL_H)
#include <sys/prctl.h> /* For prctl() and PR_SET_DUMPABLE */
#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;
char *provider;
u_int death;
u_int confirm;
} 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;
u_int parent_alive_interval = 0;
/* pathname and directory for AUTH_SOCKET */
char socket_name[MAXPATHLEN];
char socket_dir[MAXPATHLEN];
/* locking */
int locked = 0;
char *lock_passwd = NULL;
extern char *__progname;
/* Default lifetime (0 == forever) */
static int lifetime = 0;
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);
if (id->provider != NULL)
xfree(id->provider);
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);
}
/* Check confirmation of keysign request */
static int
confirm_key(Identity *id)
{
char *p;
int ret = -1;
p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
if (ask_permission("Allow use of key %s?\nKey fingerprint %s.",
id->comment, p))
ret = 0;
xfree(p);
return (ret);
}
/* 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 && (!id->confirm || confirm_key(id) == 0)) {
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) {
logit("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 odatafellows;
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);
odatafellows = datafellows;
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 && (!id->confirm || confirm_key(id) == 0))
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);
datafellows = odatafellows;
}
/* 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))
logit("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);
}
/* removes expired keys and returns number of seconds until the next expiry */
static u_int
reaper(void)
{
u_int deadline = 0, 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)
continue;
if (now >= id->death) {
debug("expiring key '%s'", id->comment);
TAILQ_REMOVE(&tab->idlist, id, next);
free_identity(id);
tab->nentries--;
} else
deadline = (deadline == 0) ? id->death :
MIN(deadline, id->death);
}
}
if (deadline == 0 || deadline <= now)
return 0;
else
return (deadline - now);
}
static void
process_add_identity(SocketEntry *e, int version)
{
Idtab *tab = idtab_lookup(version);
Identity *id;
int type, success = 0, death = 0, confirm = 0;
char *type_name, *comment;
Key *k = NULL;
#ifdef OPENSSL_HAS_ECC
BIGNUM *exponent;
EC_POINT *q;
char *curve;
#endif
u_char *cert;
u_int len;
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);
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_DSA_CERT_V00:
case KEY_DSA_CERT:
cert = buffer_get_string(&e->request, &len);
if ((k = key_from_blob(cert, len)) == NULL)
fatal("Certificate parse failed");
xfree(cert);
key_add_private(k);
buffer_get_bignum2(&e->request, k->dsa->priv_key);
break;
#ifdef OPENSSL_HAS_ECC
case KEY_ECDSA:
k = key_new_private(type);
k->ecdsa_nid = key_ecdsa_nid_from_name(type_name);
curve = buffer_get_string(&e->request, NULL);
if (k->ecdsa_nid != key_curve_name_to_nid(curve))
fatal("%s: curve names mismatch", __func__);
xfree(curve);
k->ecdsa = EC_KEY_new_by_curve_name(k->ecdsa_nid);
if (k->ecdsa == NULL)
fatal("%s: EC_KEY_new_by_curve_name failed",
__func__);
q = EC_POINT_new(EC_KEY_get0_group(k->ecdsa));
if (q == NULL)
fatal("%s: BN_new failed", __func__);
if ((exponent = BN_new()) == NULL)
fatal("%s: BN_new failed", __func__);
buffer_get_ecpoint(&e->request,
EC_KEY_get0_group(k->ecdsa), q);
buffer_get_bignum2(&e->request, exponent);
if (EC_KEY_set_public_key(k->ecdsa, q) != 1)
fatal("%s: EC_KEY_set_public_key failed",
__func__);
if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1)
fatal("%s: EC_KEY_set_private_key failed",
__func__);
if (key_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
EC_KEY_get0_public_key(k->ecdsa)) != 0)
fatal("%s: bad ECDSA public key", __func__);
if (key_ec_validate_private(k->ecdsa) != 0)
fatal("%s: bad ECDSA private key", __func__);
BN_clear_free(exponent);
EC_POINT_free(q);
break;
case KEY_ECDSA_CERT:
cert = buffer_get_string(&e->request, &len);
if ((k = key_from_blob(cert, len)) == NULL)
fatal("Certificate parse failed");
xfree(cert);
key_add_private(k);
if ((exponent = BN_new()) == NULL)
fatal("%s: BN_new failed", __func__);
buffer_get_bignum2(&e->request, exponent);
if (EC_KEY_set_private_key(k->ecdsa, exponent) != 1)
fatal("%s: EC_KEY_set_private_key failed",
__func__);
if (key_ec_validate_public(EC_KEY_get0_group(k->ecdsa),
EC_KEY_get0_public_key(k->ecdsa)) != 0 ||
key_ec_validate_private(k->ecdsa) != 0)
fatal("%s: bad ECDSA key", __func__);
BN_clear_free(exponent);
break;
#endif /* OPENSSL_HAS_ECC */
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;
case KEY_RSA_CERT_V00:
case KEY_RSA_CERT:
cert = buffer_get_string(&e->request, &len);
if ((k = key_from_blob(cert, len)) == NULL)
fatal("Certificate parse failed");
xfree(cert);
key_add_private(k);
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);
break;
default:
xfree(type_name);
buffer_clear(&e->request);
goto send;
}
xfree(type_name);
break;
}
/* enable blinding */
switch (k->type) {
case KEY_RSA:
case KEY_RSA_CERT_V00:
case KEY_RSA_CERT:
case KEY_RSA1:
if (RSA_blinding_on(k->rsa, NULL) != 1) {
error("process_add_identity: RSA_blinding_on failed");
key_free(k);
goto send;
}
break;
}
comment = buffer_get_string(&e->request, NULL);
if (k == NULL) {
xfree(comment);
goto send;
}
while (buffer_len(&e->request)) {
switch ((type = buffer_get_char(&e->request))) {
case SSH_AGENT_CONSTRAIN_LIFETIME:
death = time(NULL) + buffer_get_int(&e->request);
break;
case SSH_AGENT_CONSTRAIN_CONFIRM:
confirm = 1;
break;
default:
error("process_add_identity: "
"Unknown constraint type %d", type);
xfree(comment);
key_free(k);
goto send;
}
}
success = 1;
if (lifetime && !death)
death = time(NULL) + lifetime;
if ((id = lookup_identity(k, version)) == NULL) {
id = xcalloc(1, sizeof(Identity));
id->key = k;
TAILQ_INSERT_TAIL(&tab->idlist, id, next);
/* Increment the number of identities. */
tab->nentries++;
} else {
key_free(k);
xfree(id->comment);
}
id->comment = comment;
id->death = death;
id->confirm = confirm;
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 ENABLE_PKCS11
static void
process_add_smartcard_key(SocketEntry *e)
{
char *provider = NULL, *pin;
int i, type, version, count = 0, success = 0, death = 0, confirm = 0;
Key **keys = NULL, *k;
Identity *id;
Idtab *tab;
provider = buffer_get_string(&e->request, NULL);
pin = buffer_get_string(&e->request, NULL);
while (buffer_len(&e->request)) {
switch ((type = buffer_get_char(&e->request))) {
case SSH_AGENT_CONSTRAIN_LIFETIME:
death = time(NULL) + buffer_get_int(&e->request);
break;
case SSH_AGENT_CONSTRAIN_CONFIRM:
confirm = 1;
break;
default:
error("process_add_smartcard_key: "
"Unknown constraint type %d", type);
goto send;
}
}
if (lifetime && !death)
death = time(NULL) + lifetime;
count = pkcs11_add_provider(provider, pin, &keys);
for (i = 0; i < count; i++) {
k = keys[i];
version = k->type == KEY_RSA1 ? 1 : 2;
tab = idtab_lookup(version);
if (lookup_identity(k, version) == NULL) {
id = xcalloc(1, sizeof(Identity));
id->key = k;
id->provider = xstrdup(provider);
id->comment = xstrdup(provider); /* XXX */
id->death = death;
id->confirm = confirm;
TAILQ_INSERT_TAIL(&tab->idlist, id, next);
tab->nentries++;
success = 1;
} else {
key_free(k);
}
keys[i] = NULL;
}
send:
if (pin)
xfree(pin);
if (provider)
xfree(provider);
if (keys)
xfree(keys);
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 *provider = NULL, *pin = NULL;
int version, success = 0;
Identity *id, *nxt;
Idtab *tab;
provider = buffer_get_string(&e->request, NULL);
pin = buffer_get_string(&e->request, NULL);
xfree(pin);
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 (!strcmp(provider, id->provider)) {
TAILQ_REMOVE(&tab->idlist, id, next);
free_identity(id);
tab->nentries--;
}
}
}
if (pkcs11_del_provider(provider) == 0)
success = 1;
else
error("process_remove_smartcard_key:"
" pkcs11_del_provider failed");
xfree(provider);
buffer_put_int(&e->output, 1);
buffer_put_char(&e->output,
success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
}
#endif /* ENABLE_PKCS11 */
/* dispatch incoming messages */
static void
process_message(SocketEntry *e)
{
u_int msg_len, type;
u_char *cp;
if (buffer_len(&e->input) < 5)
return; /* Incomplete message. */
cp = buffer_ptr(&e->input);
msg_len = get_u32(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 ENABLE_PKCS11
case SSH_AGENTC_ADD_SMARTCARD_KEY:
case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
process_add_smartcard_key(e);
break;
case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
process_remove_smartcard_key(e);
break;
#endif /* ENABLE_PKCS11 */
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, new_alloc;
set_nonblock(fd);
if (fd > max_fd)
max_fd = fd;
for (i = 0; i < sockets_alloc; i++)
if (sockets[i].type == AUTH_UNUSED) {
sockets[i].fd = fd;
buffer_init(&sockets[i].input);
buffer_init(&sockets[i].output);
buffer_init(&sockets[i].request);
sockets[i].type = type;
return;
}
old_alloc = sockets_alloc;
new_alloc = sockets_alloc + 10;
sockets = xrealloc(sockets, new_alloc, sizeof(sockets[0]));
for (i = old_alloc; i < new_alloc; i++)
sockets[i].type = AUTH_UNUSED;
sockets_alloc = new_alloc;
sockets[old_alloc].fd = fd;
buffer_init(&sockets[old_alloc].input);
buffer_init(&sockets[old_alloc].output);
buffer_init(&sockets[old_alloc].request);
sockets[old_alloc].type = type;
}
static int
prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
struct timeval **tvpp)
{
u_int i, sz, deadline;
int n = 0;
static struct timeval tv;
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;
}
}
deadline = reaper();
if (parent_alive_interval != 0)
deadline = (deadline == 0) ? parent_alive_interval :
MIN(deadline, parent_alive_interval);
if (deadline == 0) {
*tvpp = NULL;
} else {
tv.tv_sec = deadline;
tv.tv_usec = 0;
*tvpp = &tv;
}
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;