-/* $OpenBSD: ssh-agent.c,v 1.81 2002/02/05 15:50:12 stevesk Exp $ */
-
+/* $OpenBSD: ssh-agent.c,v 1.162 2009/09/01 14:43:17 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
*/
#include "includes.h"
-RCSID("$OpenBSD: ssh-agent.c,v 1.81 2002/02/05 15:50:12 stevesk Exp $");
-#if defined(HAVE_SYS_QUEUE_H) && !defined(HAVE_BOGUS_SYS_QUEUE_H)
-#include <sys/queue.h>
-#else
-#include "openbsd-compat/fake-queue.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 "bufaux.h"
-#include "xmalloc.h"
-#include "getput.h"
#include "key.h"
#include "authfd.h"
#include "compat.h"
#include "log.h"
+#include "misc.h"
#ifdef SMARTCARD
-#include <openssl/engine.h>
#include "scard.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,
sock_type type;
Buffer input;
Buffer output;
+ Buffer request;
} SocketEntry;
u_int sockets_alloc = 0;
TAILQ_ENTRY(identity) next;
Key *key;
char *comment;
+ u_int death;
+ u_int confirm;
} Identity;
typedef struct {
/* 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[1024];
-char socket_dir[1024];
+char socket_name[MAXPATHLEN];
+char socket_dir[MAXPATHLEN];
+
+/* locking */
+int locked = 0;
+char *lock_passwd = NULL;
-#ifdef HAVE___PROGNAME
extern char *__progname;
-#else
-char *__progname;
-#endif
+
+/* 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 &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)
return (NULL);
}
-static void
-free_identity(Identity *id)
+/* Check confirmation of keysign request */
+static int
+confirm_key(Identity *id)
{
- key_free(id->key);
- xfree(id->comment);
- xfree(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' */
process_request_identities(SocketEntry *e, int version)
{
Idtab *tab = idtab_lookup(version);
- Buffer msg;
Identity *id;
+ Buffer msg;
buffer_init(&msg);
buffer_put_char(&msg, (version == 1) ?
static void
process_authentication_challenge1(SocketEntry *e)
{
- Identity *id;
- Key *key;
+ 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;
- u_char buf[32], mdbuf[16], session_id[16];
- u_int response_type;
+ Key *key;
buffer_init(&msg);
key = key_new(KEY_RSA1);
if ((challenge = BN_new()) == NULL)
fatal("process_authentication_challenge1: BN_new failed");
- buffer_get_int(&e->input); /* ignored */
- buffer_get_bignum(&e->input, key->rsa->e);
- buffer_get_bignum(&e->input, key->rsa->n);
- buffer_get_bignum(&e->input, challenge);
+ (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->input) == 0)
+ if (buffer_len(&e->request) == 0)
goto failure;
- buffer_get(&e->input, session_id, 16);
- response_type = buffer_get_int(&e->input);
+ 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) {
+ 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)
/* 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);
+ logit("process_authentication_challenge: bad challenge length %d", len);
goto failure;
}
memset(buf, 0, 32);
static void
process_sign_request2(SocketEntry *e)
{
- extern int datafellows;
- Key *key;
u_char *blob, *data, *signature = NULL;
u_int blen, dlen, slen = 0;
- int flags;
+ extern int datafellows;
+ int odatafellows;
+ int ok = -1, flags;
Buffer msg;
- int ok = -1;
+ Key *key;
datafellows = 0;
- blob = buffer_get_string(&e->input, &blen);
- data = buffer_get_string(&e->input, &dlen);
+ blob = buffer_get_string(&e->request, &blen);
+ data = buffer_get_string(&e->request, &dlen);
- flags = buffer_get_int(&e->input);
+ 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)
+ if (id != NULL && (!id->confirm || confirm_key(id) == 0))
ok = key_sign(id->key, &signature, &slen, data, dlen);
+ key_free(key);
}
- key_free(key);
buffer_init(&msg);
if (ok == 0) {
buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
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;
- u_int blen;
- u_int bits;
- int success = 0;
switch (version) {
case 1:
key = key_new(KEY_RSA1);
- bits = buffer_get_int(&e->input);
- buffer_get_bignum(&e->input, key->rsa->e);
- buffer_get_bignum(&e->input, key->rsa->n);
+ 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 %d, announced %d",
+ logit("Warning: identity keysize mismatch: actual %u, announced %u",
key_size(key), bits);
break;
case 2:
- blob = buffer_get_string(&e->input, &blen);
+ blob = buffer_get_string(&e->request, &blen);
key = key_from_blob(blob, blen);
xfree(blob);
break;
if (id != NULL) {
/*
* We have this key. Free the old key. Since we
- * don\'t want to leave empty slots in the middle of
+ * 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.
/* Send success. */
buffer_put_int(&e->output, 1);
buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
- return;
+}
+
+/* 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)
{
- Key *k = NULL;
- char *type_name;
- char *comment;
- int type, success = 0;
Idtab *tab = idtab_lookup(version);
+ Identity *id;
+ int type, success = 0, death = 0, confirm = 0;
+ char *type_name, *comment;
+ Key *k = NULL;
switch (version) {
case 1:
k = key_new_private(KEY_RSA1);
- buffer_get_int(&e->input); /* ignored */
- buffer_get_bignum(&e->input, k->rsa->n);
- buffer_get_bignum(&e->input, k->rsa->e);
- buffer_get_bignum(&e->input, k->rsa->d);
- buffer_get_bignum(&e->input, k->rsa->iqmp);
+ (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->input, k->rsa->q); /* p */
- buffer_get_bignum(&e->input, k->rsa->p); /* q */
+ 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->input, NULL);
+ 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->input, k->dsa->p);
- buffer_get_bignum2(&e->input, k->dsa->q);
- buffer_get_bignum2(&e->input, k->dsa->g);
- buffer_get_bignum2(&e->input, k->dsa->pub_key);
- buffer_get_bignum2(&e->input, k->dsa->priv_key);
+ 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->input, k->rsa->n);
- buffer_get_bignum2(&e->input, k->rsa->e);
- buffer_get_bignum2(&e->input, k->rsa->d);
- buffer_get_bignum2(&e->input, k->rsa->iqmp);
- buffer_get_bignum2(&e->input, k->rsa->p);
- buffer_get_bignum2(&e->input, k->rsa->q);
+ 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->input);
+ buffer_clear(&e->request);
+ goto send;
+ }
+ break;
+ }
+ /* enable blinding */
+ switch (k->type) {
+ case KEY_RSA:
+ 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->input, NULL);
+ 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 (lookup_identity(k, version) == NULL) {
- Identity *id = xmalloc(sizeof(Identity));
+ if (lifetime && !death)
+ death = time(NULL) + lifetime;
+ if ((id = lookup_identity(k, version)) == NULL) {
+ id = xmalloc(sizeof(Identity));
id->key = k;
- id->comment = comment;
TAILQ_INSERT_TAIL(&tab->idlist, id, next);
/* Increment the number of identities. */
tab->nentries++;
} else {
key_free(k);
- xfree(comment);
+ 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 SMARTCARD
static void
-process_add_smartcard_key (SocketEntry *e)
+process_add_smartcard_key(SocketEntry *e)
{
+ char *sc_reader_id = NULL, *pin;
+ int i, type, version, success = 0, death = 0, confirm = 0;
+ Key **keys, *k;
+ Identity *id;
Idtab *tab;
- Key *n = NULL, *k = NULL;
- char *sc_reader_id = NULL;
- int success = 0;
- sc_reader_id = buffer_get_string(&e->input, NULL);
- k = sc_get_key(sc_reader_id);
- xfree(sc_reader_id);
+ sc_reader_id = buffer_get_string(&e->request, NULL);
+ pin = buffer_get_string(&e->request, NULL);
- if (k == NULL) {
- error("sc_get_pubkey failed");
- 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_smartcard_key: "
+ "Unknown constraint type %d", type);
+ xfree(sc_reader_id);
+ xfree(pin);
+ goto send;
+ }
}
- success = 1;
+ if (lifetime && !death)
+ death = time(NULL) + lifetime;
- tab = idtab_lookup(1);
- k->type = KEY_RSA1;
- if (lookup_identity(k, 1) == NULL) {
- Identity *id = xmalloc(sizeof(Identity));
- n = key_new(KEY_RSA1);
- BN_copy(n->rsa->n, k->rsa->n);
- BN_copy(n->rsa->e, k->rsa->e);
- RSA_set_method(n->rsa, sc_get_engine());
- id->key = n;
- id->comment = xstrdup("rsa1 smartcard");
- TAILQ_INSERT_TAIL(&tab->idlist, id, next);
- tab->nentries++;
+ 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;
}
- k->type = KEY_RSA;
- tab = idtab_lookup(2);
- if (lookup_identity(k, 2) == NULL) {
- Identity *id = xmalloc(sizeof(Identity));
- n = key_new(KEY_RSA);
- BN_copy(n->rsa->n, k->rsa->n);
- BN_copy(n->rsa->e, k->rsa->e);
- RSA_set_method(n->rsa, sc_get_engine());
- id->key = n;
- id->comment = xstrdup("rsa smartcard");
- TAILQ_INSERT_TAIL(&tab->idlist, id, next);
- tab->nentries++;
+ 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 = sc_get_key_label(k);
+ id->death = death;
+ id->confirm = confirm;
+ TAILQ_INSERT_TAIL(&tab->idlist, id, next);
+ tab->nentries++;
+ success = 1;
+ } else {
+ key_free(k);
+ }
+ keys[i] = NULL;
}
- key_free(k);
+ xfree(keys);
send:
buffer_put_int(&e->output, 1);
buffer_put_char(&e->output,
static void
process_remove_smartcard_key(SocketEntry *e)
{
- Key *k = NULL;
- int success = 0;
- char *sc_reader_id = NULL;
+ 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->input, NULL);
- k = sc_get_key(sc_reader_id);
+ 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 (k == NULL) {
- error("sc_get_pubkey failed");
- } else {
- Identity *id;
- k->type = KEY_RSA1;
- id = lookup_identity(k, 1);
- if (id != NULL) {
- Idtab *tab = idtab_lookup(1);
+ 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);
- free_identity(id);
tab->nentries--;
- success = 1;
- }
- k->type = KEY_RSA;
- id = lookup_identity(k, 2);
- if (id != NULL) {
- Idtab *tab = idtab_lookup(2);
- TAILQ_REMOVE(&tab->idlist, id, next);
free_identity(id);
- tab->nentries--;
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);
static void
process_message(SocketEntry *e)
{
- u_int msg_len;
- u_int type;
+ 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_32BIT(cp);
+ msg_len = get_u32(cp);
if (msg_len > 256 * 1024) {
- shutdown(e->fd, SHUT_RDWR);
- close(e->fd);
- e->type = AUTH_UNUSED;
+ 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);
- type = buffer_get_char(&e->input);
+ 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);
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_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:
break;
#ifdef SMARTCARD
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:
default:
/* Unknown message. Respond with failure. */
error("Unknown message %d", type);
- buffer_clear(&e->input);
+ 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));
+ 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;
- sockets[i].type = type;
buffer_init(&sockets[i].input);
buffer_init(&sockets[i].output);
+ buffer_init(&sockets[i].request);
+ sockets[i].type = type;
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++)
+ 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[old_alloc].type = type;
+ 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, int *nallocp)
+prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
+ struct timeval **tvpp)
{
- u_int i, sz;
+ u_int i, sz, deadline;
int n = 0;
+ static struct timeval tv;
for (i = 0; i < sockets_alloc; i++) {
switch (sockets[i].type) {
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)
{
- u_int i;
- int len, sock;
+ struct sockaddr_un sunaddr;
socklen_t slen;
char buf[1024];
- struct sockaddr_un sunaddr;
+ int len, sock;
+ u_int i, orig_alloc;
+ uid_t euid;
+ gid_t egid;
- for (i = 0; i < sockets_alloc; i++)
+ for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++)
switch (sockets[i].type) {
case AUTH_UNUSED:
break;
if (FD_ISSET(sockets[i].fd, readset)) {
slen = sizeof(sunaddr);
sock = accept(sockets[i].fd,
- (struct sockaddr *) &sunaddr, &slen);
+ (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);
+ len = write(sockets[i].fd,
+ buffer_ptr(&sockets[i].output),
+ buffer_len(&sockets[i].output));
+ if (len == -1 && (errno == EAGAIN ||
+ errno == EWOULDBLOCK ||
+ errno == EINTR))
+ continue;
if (len <= 0) {
- shutdown(sockets[i].fd, SHUT_RDWR);
- close(sockets[i].fd);
- sockets[i].type = AUTH_UNUSED;
- buffer_free(&sockets[i].input);
- buffer_free(&sockets[i].output);
+ 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);
+ len = read(sockets[i].fd, buf, sizeof(buf));
+ if (len == -1 && (errno == EAGAIN ||
+ errno == EWOULDBLOCK ||
+ errno == EINTR))
+ continue;
if (len <= 0) {
- shutdown(sockets[i].fd, SHUT_RDWR);
- close(sockets[i].fd);
- sockets[i].type = AUTH_UNUSED;
- buffer_free(&sockets[i].input);
- buffer_free(&sockets[i].output);
+ close_socket(&sockets[i]);
break;
}
buffer_append(&sockets[i].input, buf, len);
}
static void
-cleanup_socket(void *p)
+cleanup_socket(void)
{
if (socket_name[0])
unlink(socket_name);
rmdir(socket_dir);
}
-static void
+void
cleanup_exit(int i)
{
- cleanup_socket(NULL);
- exit(i);
+ cleanup_socket();
+ _exit(i);
}
+/*ARGSUSED*/
static void
cleanup_handler(int sig)
{
- cleanup_socket(NULL);
+ cleanup_socket();
_exit(2);
}
static void
-check_parent_exists(int sig)
+check_parent_exists(void)
{
- int save_errno = errno;
-
if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
/* printf("Parent has died - Authentication agent exiting.\n"); */
- cleanup_handler(sig); /* safe */
+ cleanup_socket();
+ _exit(2);
}
- signal(SIGALRM, check_parent_exists);
- alarm(10);
- errno = save_errno;
}
static void
usage(void)
{
- fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
+ fprintf(stderr, "usage: %s [options] [command [arg ...]]\n",
__progname);
fprintf(stderr, "Options:\n");
fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
fprintf(stderr, " -k Kill the current agent.\n");
fprintf(stderr, " -d Debug mode.\n");
+ fprintf(stderr, " -a socket Bind agent socket to given name.\n");
+ fprintf(stderr, " -t life Default identity lifetime (seconds).\n");
exit(1);
}
int
main(int ac, char **av)
{
- int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
+ int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0;
+ int sock, fd, ch, result, saved_errno;
+ u_int nalloc;
+ char *shell, *format, *pidstr, *agentsocket = NULL;
+ fd_set *readsetp = NULL, *writesetp = NULL;
struct sockaddr_un sunaddr;
#ifdef HAVE_SETRLIMIT
struct rlimit rlim;
#endif
-#ifdef HAVE_CYGWIN
int prev_mask;
-#endif
- pid_t pid;
- char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
extern int optind;
- fd_set *readsetp = NULL, *writesetp = NULL;
+ extern char *optarg;
+ pid_t pid;
+ char pidstrbuf[1 + 3 * sizeof pid];
+ struct timeval *tvp = NULL;
+ size_t len;
+
+ /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
+ sanitise_stdfd();
+
+ /* drop */
+ setegid(getgid());
+ setgid(getgid());
+
+#if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE)
+ /* Disable ptrace on Linux without sgid bit */
+ prctl(PR_SET_DUMPABLE, 0);
+#endif
SSLeay_add_all_algorithms();
- __progname = get_progname(av[0]);
+ __progname = ssh_get_progname(av[0]);
init_rng();
seed_rng();
-#ifdef __GNU_LIBRARY__
- while ((ch = getopt(ac, av, "+cdks")) != -1) {
-#else /* __GNU_LIBRARY__ */
- while ((ch = getopt(ac, av, "cdks")) != -1) {
-#endif /* __GNU_LIBRARY__ */
+ while ((ch = getopt(ac, av, "cdksa:t:")) != -1) {
switch (ch) {
case 'c':
if (s_flag)
usage();
d_flag++;
break;
+ case 'a':
+ agentsocket = optarg;
+ break;
+ case 't':
+ if ((lifetime = convtime(optarg)) == -1) {
+ fprintf(stderr, "Invalid lifetime\n");
+ usage();
+ }
+ break;
default:
usage();
}
if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
usage();
- if (ac == 0 && !c_flag && !k_flag && !s_flag && !d_flag) {
+ if (ac == 0 && !c_flag && !s_flag) {
shell = getenv("SHELL");
- if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
+ if (shell != NULL && (len = strlen(shell)) > 2 &&
+ strncmp(shell + len - 3, "csh", 3) == 0)
c_flag = 1;
}
if (k_flag) {
+ const char *errstr = NULL;
+
pidstr = getenv(SSH_AGENTPID_ENV_NAME);
if (pidstr == NULL) {
fprintf(stderr, "%s not set, cannot kill agent\n",
SSH_AGENTPID_ENV_NAME);
exit(1);
}
- pid = atoi(pidstr);
- if (pid < 1) {
- fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
- SSH_AGENTPID_ENV_NAME, pidstr);
+ pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
+ if (errstr) {
+ fprintf(stderr,
+ "%s=\"%s\", which is not a good PID: %s\n",
+ SSH_AGENTPID_ENV_NAME, pidstr, errstr);
exit(1);
}
if (kill(pid, SIGTERM) == -1) {
format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
printf(format, SSH_AUTHSOCKET_ENV_NAME);
printf(format, SSH_AGENTPID_ENV_NAME);
- printf("echo Agent pid %d killed;\n", pid);
+ printf("echo Agent pid %ld killed;\n", (long)pid);
exit(0);
}
parent_pid = getpid();
- /* 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);
+ if (agentsocket == NULL) {
+ /* Create private directory for agent socket */
+ strlcpy(socket_dir, "/tmp/ssh-XXXXXXXXXX", 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);
}
- snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
- parent_pid);
/*
* Create socket early so it will exist before command gets run from
sock = socket(AF_UNIX, SOCK_STREAM, 0);
if (sock < 0) {
perror("socket");
+ *socket_name = '\0'; /* Don't unlink any existing file */
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) {
+ if (bind(sock, (struct sockaddr *) &sunaddr, sizeof(sunaddr)) < 0) {
perror("bind");
-#ifdef HAVE_CYGWIN
+ *socket_name = '\0'; /* Don't unlink any existing file */
umask(prev_mask);
-#endif
cleanup_exit(1);
}
-#ifdef HAVE_CYGWIN
umask(prev_mask);
-#endif
- if (listen(sock, 5) < 0) {
+ if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
perror("listen");
cleanup_exit(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 Agent pid %d;\n", parent_pid);
+ printf("echo Agent pid %ld;\n", (long)parent_pid);
goto skip;
}
pid = fork();
}
if (pid != 0) { /* Parent - execute the given command. */
close(sock);
- snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid);
+ 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 Agent pid %d;\n", pid);
+ printf("echo Agent pid %ld;\n", (long)pid);
exit(0);
}
if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
}
(void)chdir("/");
- close(0);
- close(1);
- close(2);
+ if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
+ /* XXX might close listen socket */
+ (void)dup2(fd, STDIN_FILENO);
+ (void)dup2(fd, STDOUT_FILENO);
+ (void)dup2(fd, STDERR_FILENO);
+ if (fd > 2)
+ close(fd);
+ }
#ifdef HAVE_SETRLIMIT
/* deny core dumps, since memory contains unencrypted private keys */
#endif
skip:
- fatal_add_cleanup(cleanup_socket, NULL);
new_socket(AUTH_SOCKET, sock);
- if (ac > 0) {
- signal(SIGALRM, check_parent_exists);
- alarm(10);
- }
+ if (ac > 0)
+ parent_alive_interval = 10;
idtab_init();
if (!d_flag)
signal(SIGINT, SIG_IGN);
nalloc = 0;
while (1) {
- prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
- if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
- if (errno == EINTR)
+ prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
+ result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
+ saved_errno = errno;
+ if (parent_alive_interval != 0)
+ check_parent_exists();
+ (void) reaper(); /* remove expired keys */
+ if (result < 0) {
+ if (saved_errno == EINTR)
continue;
- fatal("select: %s", strerror(errno));
- }
- after_select(readsetp, writesetp);
+ fatal("select: %s", strerror(saved_errno));
+ } else if (result > 0)
+ after_select(readsetp, writesetp);
}
/* NOTREACHED */
}
andersk / openssh.git / blobdiff