- Merge big update to OpenSSH-2.0 from OpenBSD CVS
[README.openssh2]
- interop w/ F-secure windows client
- sync documentation
- ssh_host_dsa_key not ssh_dsa_key
[auth-rsa.c]
- missing fclose
[auth.c authfile.c compat.c dsa.c dsa.h hostfile.c key.c key.h radix.c]
[readconf.c readconf.h ssh-add.c ssh-keygen.c ssh.c ssh.h sshconnect.c]
[sshd.c uuencode.c uuencode.h authfile.h]
- add DSA pubkey auth and other SSH2 fixes. use ssh-keygen -[xX]
for trading keys with the real and the original SSH, directly from the
people who invented the SSH protocol.
[auth.c auth.h authfile.c sshconnect.c auth1.c auth2.c sshconnect.h]
[sshconnect1.c sshconnect2.c]
- split auth/sshconnect in one file per protocol version
[sshconnect2.c]
- remove debug
[uuencode.c]
- add trailing =
[version.h]
- OpenSSH-2.0
[ssh-keygen.1 ssh-keygen.c]
- add -R flag: exit code indicates if RSA is alive
[sshd.c]
- remove unused
silent if -Q is specified
[ssh.h]
- host key becomes /etc/ssh_host_dsa_key
[readconf.c servconf.c ]
- ssh/sshd default to proto 1 and 2
[uuencode.c]
- remove debug
[auth2.c ssh-keygen.c sshconnect2.c sshd.c]
- xfree DSA blobs
[auth2.c serverloop.c session.c]
- cleanup logging for sshd/2, respect PasswordAuth no
[sshconnect2.c]
- less debug, respect .ssh/config
[README.openssh2 channels.c channels.h]
- clientloop.c session.c ssh.c
- support for x11-fwding, client+server
diff --git a/sshd.c b/sshd.c
index c1dcdd8..fc2d1d2 100644
--- a/sshd.c
+++ b/sshd.c
@@ -14,7 +14,7 @@
*/
#include "includes.h"
-RCSID("$OpenBSD: sshd.c,v 1.107 2000/04/19 07:05:50 deraadt Exp $");
+RCSID("$OpenBSD: sshd.c,v 1.111 2000/04/27 08:01:28 markus Exp $");
#include "xmalloc.h"
#include "rsa.h"
@@ -40,6 +40,7 @@
#include "auth.h"
#include "myproposal.h"
+#include "authfile.h"
#ifdef LIBWRAP
#include <tcpd.h>
@@ -112,8 +113,9 @@
* not very useful. Currently, memory locking is not implemented.
*/
struct {
- RSA *private_key; /* Private part of server key. */
+ RSA *private_key; /* Private part of empheral server key. */
RSA *host_key; /* Private part of host key. */
+ Key *dsa_host_key; /* Private DSA host key. */
} sensitive_data;
/*
@@ -132,6 +134,10 @@
/* session identifier, used by RSA-auth */
unsigned char session_id[16];
+/* same for ssh2 */
+unsigned char *session_id2 = NULL;
+int session_id2_len = 0;
+
/* Prototypes for various functions defined later in this file. */
void do_ssh1_kex();
void do_ssh2_kex();
@@ -224,6 +230,7 @@
* Thus there should be no concurrency control/asynchronous execution
* problems.
*/
+/* XXX do we really want this work to be done in a signal handler ? -m */
void
key_regeneration_alarm(int sig)
{
@@ -344,6 +351,13 @@
mismatch = 0;
switch(remote_major) {
case 1:
+ if (remote_minor == 99) {
+ if (options.protocol & SSH_PROTO_2)
+ enable_compat20();
+ else
+ mismatch = 1;
+ break;
+ }
if (!(options.protocol & SSH_PROTO_1)) {
mismatch = 1;
break;
@@ -355,12 +369,6 @@
/* note that this disables agent-forwarding */
enable_compat13();
}
- if (remote_minor == 99) {
- if (options.protocol & SSH_PROTO_2)
- enable_compat20();
- else
- mismatch = 1;
- }
break;
case 2:
if (options.protocol & SSH_PROTO_2) {
@@ -386,6 +394,20 @@
server_version_string, client_version_string);
fatal_cleanup();
}
+ if (compat20)
+ packet_set_ssh2_format();
+}
+
+
+void
+destroy_sensitive_data(void)
+{
+ /* Destroy the private and public keys. They will no longer be needed. */
+ RSA_free(public_key);
+ RSA_free(sensitive_data.private_key);
+ RSA_free(sensitive_data.host_key);
+ if (sensitive_data.dsa_host_key != NULL)
+ key_free(sensitive_data.dsa_host_key);
}
/*
@@ -399,12 +421,11 @@
int opt, sock_in = 0, sock_out = 0, newsock, i, fdsetsz, on = 1;
pid_t pid;
socklen_t fromlen;
- int silentrsa = 0;
+ int silent = 0;
fd_set *fdset;
struct sockaddr_storage from;
const char *remote_ip;
int remote_port;
- char *comment;
FILE *f;
struct linger linger;
struct addrinfo *ai;
@@ -441,7 +462,7 @@
inetd_flag = 1;
break;
case 'Q':
- silentrsa = 1;
+ silent = 1;
break;
case 'q':
options.log_level = SYSLOG_LEVEL_QUIET;
@@ -497,27 +518,14 @@
log_init(av0,
options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
options.log_facility == -1 ? SYSLOG_FACILITY_AUTH : options.log_facility,
- !inetd_flag);
+ !silent && !inetd_flag);
- /* check if RSA support exists */
- if (rsa_alive() == 0) {
- if (silentrsa == 0)
- printf("sshd: no RSA support in libssl and libcrypto -- exiting. See ssl(8)\n");
- log("no RSA support in libssl and libcrypto -- exiting. See ssl(8)");
- exit(1);
- }
/* Read server configuration options from the configuration file. */
read_server_config(&options, config_file_name);
/* Fill in default values for those options not explicitly set. */
fill_default_server_options(&options);
- /* Check certain values for sanity. */
- if (options.server_key_bits < 512 ||
- options.server_key_bits > 32768) {
- fprintf(stderr, "Bad server key size.\n");
- exit(1);
- }
/* Check that there are no remaining arguments. */
if (optind < ac) {
fprintf(stderr, "Extra argument %s.\n", av[optind]);
@@ -526,26 +534,79 @@
debug("sshd version %.100s", SSH_VERSION);
- sensitive_data.host_key = RSA_new();
- errno = 0;
- /* Load the host key. It must have empty passphrase. */
- if (!load_private_key(options.host_key_file, "",
- sensitive_data.host_key, &comment)) {
- error("Could not load host key: %.200s: %.100s",
- options.host_key_file, strerror(errno));
+ sensitive_data.dsa_host_key = NULL;
+ sensitive_data.host_key = NULL;
+
+ /* check if RSA support exists */
+ if ((options.protocol & SSH_PROTO_1) &&
+ rsa_alive() == 0) {
+ log("no RSA support in libssl and libcrypto. See ssl(8)");
+ log("Disabling protocol version 1");
+ options.protocol &= ~SSH_PROTO_1;
+ }
+ /* Load the RSA/DSA host key. It must have empty passphrase. */
+ if (options.protocol & SSH_PROTO_1) {
+ Key k;
+ sensitive_data.host_key = RSA_new();
+ k.type = KEY_RSA;
+ k.rsa = sensitive_data.host_key;
+ errno = 0;
+ if (!load_private_key(options.host_key_file, "", &k, NULL)) {
+ error("Could not load host key: %.200s: %.100s",
+ options.host_key_file, strerror(errno));
+ log("Disabling protocol version 1");
+ options.protocol &= ~SSH_PROTO_1;
+ }
+ k.rsa = NULL;
+ }
+ if (options.protocol & SSH_PROTO_2) {
+ sensitive_data.dsa_host_key = key_new(KEY_DSA);
+ if (!load_private_key(options.dsa_key_file, "", sensitive_data.dsa_host_key, NULL)) {
+ error("Could not load DSA host key: %.200s", options.dsa_key_file);
+ log("Disabling protocol version 2");
+ options.protocol &= ~SSH_PROTO_2;
+ }
+ }
+ if (! options.protocol & (SSH_PROTO_1|SSH_PROTO_2)) {
+ if (silent == 0)
+ fprintf(stderr, "sshd: no hostkeys available -- exiting.\n");
+ log("sshd: no hostkeys available -- exiting.\n");
exit(1);
}
- xfree(comment);
- /* Initialize the log (it is reinitialized below in case we
- forked). */
+ /* Check certain values for sanity. */
+ if (options.protocol & SSH_PROTO_1) {
+ if (options.server_key_bits < 512 ||
+ options.server_key_bits > 32768) {
+ fprintf(stderr, "Bad server key size.\n");
+ exit(1);
+ }
+ /*
+ * Check that server and host key lengths differ sufficiently. This
+ * is necessary to make double encryption work with rsaref. Oh, I
+ * hate software patents. I dont know if this can go? Niels
+ */
+ if (options.server_key_bits >
+ BN_num_bits(sensitive_data.host_key->n) - SSH_KEY_BITS_RESERVED &&
+ options.server_key_bits <
+ BN_num_bits(sensitive_data.host_key->n) + SSH_KEY_BITS_RESERVED) {
+ options.server_key_bits =
+ BN_num_bits(sensitive_data.host_key->n) + SSH_KEY_BITS_RESERVED;
+ debug("Forcing server key to %d bits to make it differ from host key.",
+ options.server_key_bits);
+ }
+ }
+
+ /* Initialize the log (it is reinitialized below in case we forked). */
if (debug_flag && !inetd_flag)
log_stderr = 1;
log_init(av0, options.log_level, options.log_facility, log_stderr);
- /* If not in debugging mode, and not started from inetd,
- disconnect from the controlling terminal, and fork. The
- original process exits. */
+ /*
+ * If not in debugging mode, and not started from inetd, disconnect
+ * from the controlling terminal, and fork. The original process
+ * exits.
+ */
if (!debug_flag && !inetd_flag) {
#ifdef TIOCNOTTY
int fd;
@@ -565,18 +626,6 @@
/* Reinitialize the log (because of the fork above). */
log_init(av0, options.log_level, options.log_facility, log_stderr);
- /* Check that server and host key lengths differ sufficiently.
- This is necessary to make double encryption work with rsaref.
- Oh, I hate software patents. I dont know if this can go? Niels */
- if (options.server_key_bits >
- BN_num_bits(sensitive_data.host_key->n) - SSH_KEY_BITS_RESERVED &&
- options.server_key_bits <
- BN_num_bits(sensitive_data.host_key->n) + SSH_KEY_BITS_RESERVED) {
- options.server_key_bits =
- BN_num_bits(sensitive_data.host_key->n) + SSH_KEY_BITS_RESERVED;
- debug("Forcing server key to %d bits to make it differ from host key.",
- options.server_key_bits);
- }
/* Do not display messages to stdout in RSA code. */
rsa_set_verbose(0);
@@ -594,20 +643,22 @@
s2 = dup(s1);
sock_in = dup(0);
sock_out = dup(1);
- /* We intentionally do not close the descriptors 0, 1, and 2
- as our code for setting the descriptors won\'t work
- if ttyfd happens to be one of those. */
+ /*
+ * We intentionally do not close the descriptors 0, 1, and 2
+ * as our code for setting the descriptors won\'t work if
+ * ttyfd happens to be one of those.
+ */
debug("inetd sockets after dupping: %d, %d", sock_in, sock_out);
- public_key = RSA_new();
- sensitive_data.private_key = RSA_new();
-
- /* XXX check options.protocol */
- log("Generating %d bit RSA key.", options.server_key_bits);
- rsa_generate_key(sensitive_data.private_key, public_key,
- options.server_key_bits);
- arc4random_stir();
- log("RSA key generation complete.");
+ if (options.protocol & SSH_PROTO_1) {
+ public_key = RSA_new();
+ sensitive_data.private_key = RSA_new();
+ log("Generating %d bit RSA key.", options.server_key_bits);
+ rsa_generate_key(sensitive_data.private_key, public_key,
+ options.server_key_bits);
+ arc4random_stir();
+ log("RSA key generation complete.");
+ }
} else {
for (ai = options.listen_addrs; ai; ai = ai->ai_next) {
if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
@@ -684,19 +735,20 @@
fclose(f);
}
}
+ if (options.protocol & SSH_PROTO_1) {
+ public_key = RSA_new();
+ sensitive_data.private_key = RSA_new();
- public_key = RSA_new();
- sensitive_data.private_key = RSA_new();
+ log("Generating %d bit RSA key.", options.server_key_bits);
+ rsa_generate_key(sensitive_data.private_key, public_key,
+ options.server_key_bits);
+ arc4random_stir();
+ log("RSA key generation complete.");
- log("Generating %d bit RSA key.", options.server_key_bits);
- rsa_generate_key(sensitive_data.private_key, public_key,
- options.server_key_bits);
- arc4random_stir();
- log("RSA key generation complete.");
-
- /* Schedule server key regeneration alarm. */
- signal(SIGALRM, key_regeneration_alarm);
- alarm(options.key_regeneration_time);
+ /* Schedule server key regeneration alarm. */
+ signal(SIGALRM, key_regeneration_alarm);
+ alarm(options.key_regeneration_time);
+ }
/* Arrange to restart on SIGHUP. The handler needs listen_sock. */
signal(SIGHUP, sighup_handler);
@@ -1069,9 +1121,7 @@
sensitive_data.private_key->n);
/* Destroy the private and public keys. They will no longer be needed. */
- RSA_free(public_key);
- RSA_free(sensitive_data.private_key);
- RSA_free(sensitive_data.host_key);
+ destroy_sensitive_data();
/*
* Extract session key from the decrypted integer. The key is in the
@@ -1130,7 +1180,6 @@
unsigned char *kbuf;
unsigned char *hash;
Kex *kex;
- Key *server_host_key;
char *cprop[PROPOSAL_MAX];
char *sprop[PROPOSAL_MAX];
@@ -1231,8 +1280,8 @@
memset(kbuf, 0, klen);
xfree(kbuf);
- server_host_key = dsa_get_serverkey(options.dsa_key_file);
- dsa_make_serverkey_blob(server_host_key, &server_host_key_blob, &sbloblen);
+ /* XXX precompute? */
+ dsa_make_key_blob(sensitive_data.dsa_host_key, &server_host_key_blob, &sbloblen);
/* calc H */ /* XXX depends on 'kex' */
hash = kex_hash(
@@ -1255,10 +1304,17 @@
fprintf(stderr, "%02x", (hash[i])&0xff);
fprintf(stderr, "\n");
#endif
+ /* save session id := H */
+ /* XXX hashlen depends on KEX */
+ session_id2_len = 20;
+ session_id2 = xmalloc(session_id2_len);
+ memcpy(session_id2, hash, session_id2_len);
+
/* sign H */
- dsa_sign(server_host_key, &signature, &slen, hash, 20);
- /* hashlen depends on KEX */
- key_free(server_host_key);
+ /* XXX hashlen depends on KEX */
+ dsa_sign(sensitive_data.dsa_host_key, &signature, &slen, hash, 20);
+
+ destroy_sensitive_data();
/* send server hostkey, DH pubkey 'f' and singed H */
packet_start(SSH2_MSG_KEXDH_REPLY);
@@ -1267,6 +1323,7 @@
packet_put_string((char *)signature, slen);
packet_send();
xfree(signature);
+ xfree(server_host_key_blob);
packet_write_wait();
kex_derive_keys(kex, hash, shared_secret);