-/* $OpenBSD: ssh-agent.c,v 1.37 2000/09/21 11:07:51 markus Exp $ */
-
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* incompatible with the protocol description in the RFC file, it must be
* called by a name other than "ssh" or "Secure Shell".
*
- * SSH2 implementation,
- * Copyright (c) 2000 Markus Friedl. All rights reserved.
+ * 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
*/
#include "includes.h"
-RCSID("$OpenBSD: ssh-agent.c,v 1.37 2000/09/21 11:07:51 markus Exp $");
+#include "openbsd-compat/sys-queue.h"
+RCSID("$OpenBSD: ssh-agent.c,v 1.113 2003/09/19 11:29:40 markus Exp $");
+
+#include <openssl/evp.h>
+#include <openssl/md5.h>
#include "ssh.h"
#include "rsa.h"
#include "buffer.h"
#include "bufaux.h"
#include "xmalloc.h"
-#include "packet.h"
#include "getput.h"
-#include "mpaux.h"
-
-#include <openssl/evp.h>
-#include <openssl/md5.h>
-#include <openssl/dsa.h>
-#include <openssl/rsa.h>
#include "key.h"
#include "authfd.h"
-#include "dsa.h"
-#include "kex.h"
#include "compat.h"
+#include "log.h"
+#include "readpass.h"
+#include "misc.h"
+
+#ifdef SMARTCARD
+#include "scard.h"
+#endif
+
+typedef enum {
+ AUTH_UNUSED,
+ AUTH_SOCKET,
+ AUTH_CONNECTION
+} sock_type;
typedef struct {
int fd;
- enum {
- AUTH_UNUSED, AUTH_SOCKET, AUTH_CONNECTION
- } type;
+ sock_type type;
Buffer input;
Buffer output;
+ Buffer request;
} SocketEntry;
-unsigned int sockets_alloc = 0;
+u_int sockets_alloc = 0;
SocketEntry *sockets = NULL;
-typedef struct {
+typedef struct identity {
+ TAILQ_ENTRY(identity) next;
Key *key;
char *comment;
+ u_int death;
+ u_int confirm;
} Identity;
typedef struct {
int nentries;
- Identity *identities;
+ TAILQ_HEAD(idqueue, identity) idlist;
} Idtab;
/* private key table, one per protocol version */
char socket_name[1024];
char socket_dir[1024];
+/* locking */
+int locked = 0;
+char *lock_passwd = NULL;
+
#ifdef HAVE___PROGNAME
extern char *__progname;
-#else /* HAVE___PROGNAME */
-static const char *__progname = "ssh-agent";
-#endif /* HAVE___PROGNAME */
+#else
+char *__progname;
+#endif
-void
+/* 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++){
- idtable[i].identities = NULL;
+
+ for (i = 0; i <=2; i++) {
+ TAILQ_INIT(&idtable[i].idlist);
idtable[i].nentries = 0;
}
}
/* return private key table for requested protocol version */
-Idtab *
+static Idtab *
idtab_lookup(int version)
{
if (version < 1 || version > 2)
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 */
-Key *
-lookup_private_key(Key *key, int *idx, int version)
+static Identity *
+lookup_identity(Key *key, int version)
{
- int i;
+ Identity *id;
+
Idtab *tab = idtab_lookup(version);
- for (i = 0; i < tab->nentries; i++) {
- if (key_equal(key, tab->identities[i].key)) {
- if (idx != NULL)
- *idx = i;
- return tab->identities[i].key;
- }
+ TAILQ_FOREACH(id, &tab->idlist, next) {
+ if (key_equal(key, id->key))
+ return (id);
}
- return NULL;
+ return (NULL);
+}
+
+/* Check confirmation of keysign request */
+static int
+confirm_key(Identity *id)
+{
+ char *p, prompt[1024];
+ int ret = -1;
+
+ p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
+ snprintf(prompt, sizeof(prompt), "Allow use of key %s?\n"
+ "Key fingerprint %s.", id->comment, p);
+ xfree(p);
+ p = read_passphrase(prompt, RP_ALLOW_EOF);
+ if (p != NULL) {
+ /*
+ * Accept empty responses and responses consisting
+ * of the word "yes" as affirmative.
+ */
+ if (*p == '\0' || *p == '\n' || strcasecmp(p, "yes") == 0)
+ ret = 0;
+ xfree(p);
+ }
+ return (ret);
}
/* send list of supported public keys to 'client' */
-void
+static void
process_request_identities(SocketEntry *e, int version)
{
Idtab *tab = idtab_lookup(version);
+ Identity *id;
Buffer msg;
- int i;
buffer_init(&msg);
buffer_put_char(&msg, (version == 1) ?
SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
buffer_put_int(&msg, tab->nentries);
- for (i = 0; i < tab->nentries; i++) {
- Identity *id = &tab->identities[i];
- if (id->key->type == KEY_RSA) {
+ 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 {
- unsigned char *blob;
- unsigned int blen;
- dsa_make_key_blob(id->key, &blob, &blen);
+ u_char *blob;
+ u_int blen;
+ key_to_blob(id->key, &blob, &blen);
buffer_put_string(&msg, blob, blen);
xfree(blob);
}
}
/* ssh1 only */
-void
+static void
process_authentication_challenge1(SocketEntry *e)
{
- Key *key, *private;
+ 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;
- unsigned char buf[32], mdbuf[16], session_id[16];
- unsigned int response_type;
+ Key *key;
buffer_init(&msg);
- key = key_new(KEY_RSA);
- challenge = BN_new();
+ 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, (char *) 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;
- private = lookup_private_key(key, NULL, 1);
- if (private != NULL) {
+ 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. */
- rsa_private_decrypt(challenge, challenge, private->rsa);
+ 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);
+ logit("process_authentication_challenge: bad challenge length %d", len);
goto failure;
}
memset(buf, 0, 32);
}
/* ssh2 only */
-void
+static void
process_sign_request2(SocketEntry *e)
{
+ u_char *blob, *data, *signature = NULL;
+ u_int blen, dlen, slen = 0;
extern int datafellows;
- Key *key, *private;
- unsigned char *blob, *data, *signature = NULL;
- unsigned int blen, dlen, slen = 0;
- int flags;
+ 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);
- flags = buffer_get_int(&e->input);
+ 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 = dsa_key_from_blob(blob, blen);
+ key = key_from_blob(blob, blen);
if (key != NULL) {
- private = lookup_private_key(key, NULL, 2);
- if (private != NULL)
- ok = dsa_sign(private, &signature, &slen, data, dlen);
+ 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);
}
/* shared */
-void
+static void
process_remove_identity(SocketEntry *e, int version)
{
- Key *key = NULL, *private;
- unsigned char *blob;
- unsigned int blen;
- unsigned int bits;
+ u_int blen, bits;
int success = 0;
+ Key *key = NULL;
+ u_char *blob;
- switch(version){
+ switch (version) {
case 1:
- key = key_new(KEY_RSA);
- bits = buffer_get_int(&e->input);
- buffer_get_bignum(&e->input, key->rsa->e);
- buffer_get_bignum(&e->input, key->rsa->n);
+ 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 %d, announced %d",
- key_size(key), bits);
+ logit("Warning: identity keysize mismatch: actual %u, announced %u",
+ key_size(key), bits);
break;
case 2:
- blob = buffer_get_string(&e->input, &blen);
- key = dsa_key_from_blob(blob, blen);
+ blob = buffer_get_string(&e->request, &blen);
+ key = key_from_blob(blob, blen);
xfree(blob);
break;
}
if (key != NULL) {
- int idx;
- private = lookup_private_key(key, &idx, version);
- if (private != 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 copy
- * data from the last entry.
+ * 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);
- key_free(tab->identities[idx].key);
- xfree(tab->identities[idx].comment);
- if (idx != tab->nentries)
- tab->identities[idx] = tab->identities[tab->nentries];
+ 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;
}
success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
}
-void
+static void
process_remove_all_identities(SocketEntry *e, int version)
{
- unsigned int i;
Idtab *tab = idtab_lookup(version);
+ Identity *id;
/* Loop over all identities and clear the keys. */
- for (i = 0; i < tab->nentries; i++) {
- key_free(tab->identities[i].key);
- xfree(tab->identities[i].comment);
+ 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. */
/* Send success. */
buffer_put_int(&e->output, 1);
buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
- return;
}
-void
+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)
{
- Key *k = NULL;
- RSA *rsa;
- BIGNUM *aux;
- BN_CTX *ctx;
- char *type;
- char *comment;
- int success = 0;
Idtab *tab = idtab_lookup(version);
+ int type, success = 0, death = 0, confirm = 0;
+ char *type_name, *comment;
+ Key *k = NULL;
switch (version) {
case 1:
- k = key_new(KEY_RSA);
- rsa = k->rsa;
-
- /* allocate mem for private key */
- /* XXX rsa->n and rsa->e are already allocated */
- rsa->d = BN_new();
- rsa->iqmp = BN_new();
- rsa->q = BN_new();
- rsa->p = BN_new();
- rsa->dmq1 = BN_new();
- rsa->dmp1 = BN_new();
-
- buffer_get_int(&e->input); /* ignored */
-
- buffer_get_bignum(&e->input, rsa->n);
- buffer_get_bignum(&e->input, rsa->e);
- buffer_get_bignum(&e->input, rsa->d);
- buffer_get_bignum(&e->input, rsa->iqmp);
+ 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->input, rsa->q); /* p */
- buffer_get_bignum(&e->input, rsa->p); /* q */
+ buffer_get_bignum(&e->request, k->rsa->q); /* p */
+ buffer_get_bignum(&e->request, k->rsa->p); /* q */
/* Generate additional parameters */
- aux = BN_new();
- ctx = BN_CTX_new();
-
- BN_sub(aux, rsa->q, BN_value_one());
- BN_mod(rsa->dmq1, rsa->d, aux, ctx);
-
- BN_sub(aux, rsa->p, BN_value_one());
- BN_mod(rsa->dmp1, rsa->d, aux, ctx);
-
- BN_clear_free(aux);
- BN_CTX_free(ctx);
-
+ rsa_generate_additional_parameters(k->rsa);
break;
case 2:
- type = buffer_get_string(&e->input, NULL);
- if (strcmp(type, KEX_DSS)) {
- buffer_clear(&e->input);
- xfree(type);
+ 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;
}
- xfree(type);
-
- k = key_new(KEY_DSA);
-
- /* allocate mem for private key */
- k->dsa->priv_key = BN_new();
-
- 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);
-
break;
}
-
- comment = buffer_get_string(&e->input, NULL);
+ /* 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->request, NULL);
if (k == NULL) {
xfree(comment);
goto send;
}
success = 1;
- if (lookup_private_key(k, NULL, version) == NULL) {
- if (tab->nentries == 0)
- tab->identities = xmalloc(sizeof(Identity));
- else
- tab->identities = xrealloc(tab->identities,
- (tab->nentries + 1) * sizeof(Identity));
- tab->identities[tab->nentries].key = k;
- tab->identities[tab->nentries].comment = comment;
+ 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;
+ case SSH_AGENT_CONSTRAIN_CONFIRM:
+ confirm = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ if (lifetime && !death)
+ death = time(NULL) + lifetime;
+ if (lookup_identity(k, version) == NULL) {
+ Identity *id = xmalloc(sizeof(Identity));
+ id->key = k;
+ id->comment = comment;
+ id->death = death;
+ id->confirm = confirm;
+ TAILQ_INSERT_TAIL(&tab->idlist, id, next);
/* Increment the number of identities. */
tab->nentries++;
} else {
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, death = 0, confirm = 0;
+ Key **keys, *k;
+ Identity *id;
+ Idtab *tab;
+
+ sc_reader_id = buffer_get_string(&e->request, NULL);
+ pin = buffer_get_string(&e->request, NULL);
+
+ 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;
+ case SSH_AGENT_CONSTRAIN_CONFIRM:
+ confirm = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ if (lifetime && !death)
+ death = time(NULL) + lifetime;
+
+ 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 = 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;
+ }
+ 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 */
-void
+static void
process_message(SocketEntry *e)
{
- unsigned int msg_len;
- unsigned int type;
- unsigned char *cp;
+ u_int msg_len, type;
+ u_char *cp;
+
+ /* kill dead keys */
+ reaper();
+
if (buffer_len(&e->input) < 5)
return; /* Incomplete message. */
- cp = (unsigned char *) buffer_ptr(&e->input);
+ cp = buffer_ptr(&e->input);
msg_len = GET_32BIT(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:
case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
process_remove_all_identities(e, 2);
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:
+ process_remove_smartcard_key(e);
+ break;
+#endif /* SMARTCARD */
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;
}
}
-void
-new_socket(int type, int fd)
+static void
+new_socket(sock_type type, int fd)
{
- unsigned int i, old_alloc;
+ u_int i, old_alloc, new_alloc;
+
if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
error("fcntl O_NONBLOCK: %s", strerror(errno));
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;
+ new_alloc = sockets_alloc + 10;
if (sockets)
- sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
+ sockets = xrealloc(sockets, new_alloc * sizeof(sockets[0]));
else
- sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
- for (i = old_alloc; i < sockets_alloc; i++)
+ sockets = xmalloc(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;
}
-void
-prepare_select(fd_set *readset, fd_set *writeset)
+static int
+prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
{
- unsigned int i;
- for (i = 0; i < sockets_alloc; i++)
+ u_int i, sz;
+ int n = 0;
+
+ for (i = 0; i < sockets_alloc; i++) {
switch (sockets[i].type) {
case AUTH_SOCKET:
case AUTH_CONNECTION:
- FD_SET(sockets[i].fd, readset);
- if (buffer_len(&sockets[i].output) > 0)
- FD_SET(sockets[i].fd, writeset);
+ n = MAX(n, sockets[i].fd);
break;
case AUTH_UNUSED:
break;
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);
}
-void
+static void
after_select(fd_set *readset, fd_set *writeset)
{
- unsigned 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;
+ uid_t euid;
+ gid_t egid;
for (i = 0; i < sockets_alloc; i++)
switch (sockets[i].type) {
case AUTH_SOCKET:
if (FD_ISSET(sockets[i].fd, readset)) {
slen = sizeof(sunaddr);
- sock = accept(sockets[i].fd, (struct sockaddr *) & sunaddr, &slen);
+ sock = accept(sockets[i].fd,
+ (struct sockaddr *) &sunaddr, &slen);
if (sock < 0) {
- perror("accept from AUTH_SOCKET");
+ 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);
case AUTH_CONNECTION:
if (buffer_len(&sockets[i].output) > 0 &&
FD_ISSET(sockets[i].fd, writeset)) {
- len = write(sockets[i].fd, buffer_ptr(&sockets[i].output),
- buffer_len(&sockets[i].output));
+ 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) {
- 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)) {
- len = read(sockets[i].fd, buf, sizeof(buf));
+ do {
+ len = read(sockets[i].fd, buf, sizeof(buf));
+ if (len == -1 && (errno == EAGAIN ||
+ errno == EINTR))
+ continue;
+ break;
+ } while (1);
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);
}
}
-void
-check_parent_exists(int sig)
+static void
+cleanup_socket(void)
{
- if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
- /* printf("Parent has died - Authentication agent exiting.\n"); */
- exit(1);
- }
- signal(SIGALRM, check_parent_exists);
- alarm(10);
+ if (socket_name[0])
+ unlink(socket_name);
+ if (socket_dir[0])
+ rmdir(socket_dir);
}
-void
-cleanup_socket(void)
+static void
+cleanup_exit(int i)
{
- unlink(socket_name);
- rmdir(socket_dir);
+ cleanup_socket();
+ _exit(i);
}
-void
-cleanup_exit(int i)
+static void
+cleanup_handler(int sig)
{
cleanup_socket();
- exit(i);
+ _exit(2);
}
void
-usage()
+fatal(const char *fmt,...)
+{
+ va_list args;
+ va_start(args, fmt);
+ do_log(SYSLOG_LEVEL_FATAL, fmt, args);
+ va_end(args);
+ cleanup_socket();
+ _exit(255);
+}
+
+static void
+check_parent_exists(int sig)
+{
+ 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 */
+ }
+ mysignal(SIGALRM, check_parent_exists);
+ alarm(10);
+ errno = save_errno;
+}
+
+static void
+usage(void)
{
- fprintf(stderr, "ssh-agent version %s\n", SSH_VERSION);
- fprintf(stderr, "Usage: %s [-c | -s] [-k] [command {args...]]\n",
- __progname);
+ fprintf(stderr, "Usage: %s [options] [command [args ...]]\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)
{
- fd_set readset, writeset;
- int sock, c_flag = 0, k_flag = 0, s_flag = 0, ch;
+ int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0;
+ int sock, fd, ch, nalloc;
+ char *shell, *format, *pidstr, *agentsocket = NULL;
+ fd_set *readsetp = NULL, *writesetp = NULL;
struct sockaddr_un sunaddr;
- pid_t pid;
- char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
+#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];
+
+ /* drop */
+ setegid(getgid());
+ setgid(getgid());
+
+ SSLeay_add_all_algorithms();
+
+ __progname = ssh_get_progname(av[0]);
init_rng();
-
- /* check if RSA support exists */
- if (rsa_alive() == 0) {
- fprintf(stderr,
- "%s: no RSA support in libssl and libcrypto. See ssl(8).\n",
- __progname);
- exit(1);
- }
-#ifdef __GNU_LIBRARY__
- while ((ch = getopt(ac, av, "+cks")) != -1) {
-#else /* __GNU_LIBRARY__ */
- while ((ch = getopt(ac, av, "cks")) != -1) {
-#endif /* __GNU_LIBRARY__ */
+ seed_rng();
+
+ while ((ch = getopt(ac, av, "cdksa:t:")) != -1) {
switch (ch) {
case 'c':
if (s_flag)
usage();
s_flag++;
break;
+ case 'd':
+ if (d_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();
}
ac -= optind;
av += optind;
- if (ac > 0 && (c_flag || k_flag || s_flag))
+ if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
usage();
- if (ac == 0 && !c_flag && !k_flag && !s_flag) {
+ if (ac == 0 && !c_flag && !s_flag) {
shell = getenv("SHELL");
if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
c_flag = 1;
pidstr = getenv(SSH_AGENTPID_ENV_NAME);
if (pidstr == NULL) {
fprintf(stderr, "%s not set, cannot kill agent\n",
- SSH_AGENTPID_ENV_NAME);
+ SSH_AGENTPID_ENV_NAME);
exit(1);
}
pid = atoi(pidstr);
- if (pid < 1) { /* XXX PID_MAX check too */
- /* Yes, PID_MAX check please */
+ if (pid < 1) {
fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
- SSH_AGENTPID_ENV_NAME, pidstr);
+ SSH_AGENTPID_ENV_NAME, pidstr);
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-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);
}
- 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
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);
}
- if (listen(sock, 5) < 0) {
+#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 Agent pid %ld;\n", (long)parent_pid);
+ goto skip;
+ }
pid = fork();
if (pid == -1) {
perror("fork");
- exit(1);
+ cleanup_exit(1);
}
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);
+ SSH_AUTHSOCKET_ENV_NAME);
printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
- SSH_AGENTPID_ENV_NAME);
- printf("echo Agent pid %d;\n", pid);
+ SSH_AGENTPID_ENV_NAME);
+ printf("echo Agent pid %ld;\n", (long)pid);
exit(0);
}
if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
perror(av[0]);
exit(1);
}
- close(0);
- close(1);
- close(2);
+ /* child */
+ log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
if (setsid() == -1) {
- perror("setsid");
+ error("setsid: %s", strerror(errno));
cleanup_exit(1);
}
- if (atexit(cleanup_socket) < 0) {
- perror("atexit");
+
+ (void)chdir("/");
+ 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 */
+ 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:
new_socket(AUTH_SOCKET, sock);
if (ac > 0) {
- signal(SIGALRM, check_parent_exists);
+ mysignal(SIGALRM, check_parent_exists);
alarm(10);
}
idtab_init();
- signal(SIGINT, SIG_IGN);
+ if (!d_flag)
+ signal(SIGINT, SIG_IGN);
signal(SIGPIPE, SIG_IGN);
- signal(SIGHUP, cleanup_exit);
- signal(SIGTERM, cleanup_exit);
+ signal(SIGHUP, cleanup_handler);
+ signal(SIGTERM, cleanup_handler);
+ nalloc = 0;
+
while (1) {
- FD_ZERO(&readset);
- FD_ZERO(&writeset);
- prepare_select(&readset, &writeset);
- if (select(max_fd + 1, &readset, &writeset, NULL, NULL) < 0) {
+ prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
+ if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
if (errno == EINTR)
continue;
- exit(1);
+ fatal("select: %s", strerror(errno));
}
- after_select(&readset, &writeset);
+ after_select(readsetp, writesetp);
}
/* NOTREACHED */
}