* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- * Created: Sat Mar 18 22:15:47 1995 ylo
* Code to connect to a remote host, and to perform the client side of the
* login (authentication) dialog.
*
+ * 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".
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect1.c,v 1.3 2000/05/08 17:12:16 markus Exp $");
+RCSID("$OpenBSD: sshconnect1.c,v 1.27 2001/02/15 23:19:59 markus Exp $");
#include <openssl/bn.h>
-#include <openssl/dsa.h>
-#include <openssl/rsa.h>
#include <openssl/evp.h>
+#ifdef KRB4
+#include <krb.h>
+#endif
+#ifdef AFS
+#include <kafs.h>
+#include "radix.h"
+#endif
+
+#include "ssh.h"
+#include "ssh1.h"
#include "xmalloc.h"
#include "rsa.h"
-#include "ssh.h"
#include "buffer.h"
#include "packet.h"
-#include "authfd.h"
-#include "cipher.h"
#include "mpaux.h"
#include "uidswap.h"
+#include "log.h"
#include "readconf.h"
#include "key.h"
+#include "authfd.h"
#include "sshconnect.h"
#include "authfile.h"
+#include "readpass.h"
+#include "cipher.h"
+#include "canohost.h"
/* Session id for the current session. */
-unsigned char session_id[16];
-unsigned int supported_authentications = 0;
+u_char session_id[16];
+u_int supported_authentications = 0;
extern Options options;
extern char *__progname;
* authenticate using the agent.
*/
int
-try_agent_authentication()
+try_agent_authentication(void)
{
- int status, type;
+ int type;
char *comment;
AuthenticationConnection *auth;
- unsigned char response[16];
- unsigned int i;
- BIGNUM *e, *n, *challenge;
+ u_char response[16];
+ u_int i;
+ int plen, clen;
+ Key *key;
+ BIGNUM *challenge;
/* Get connection to the agent. */
auth = ssh_get_authentication_connection();
if (!auth)
return 0;
- e = BN_new();
- n = BN_new();
challenge = BN_new();
/* Loop through identities served by the agent. */
- for (status = ssh_get_first_identity(auth, e, n, &comment);
- status;
- status = ssh_get_next_identity(auth, e, n, &comment)) {
- int plen, clen;
+ for (key = ssh_get_first_identity(auth, &comment, 1);
+ key != NULL;
+ key = ssh_get_next_identity(auth, &comment, 1)) {
/* Try this identity. */
debug("Trying RSA authentication via agent with '%.100s'", comment);
/* Tell the server that we are willing to authenticate using this key. */
packet_start(SSH_CMSG_AUTH_RSA);
- packet_put_bignum(n);
+ packet_put_bignum(key->rsa->n);
packet_send();
packet_write_wait();
does not support RSA authentication. */
if (type == SSH_SMSG_FAILURE) {
debug("Server refused our key.");
+ key_free(key);
continue;
}
/* Otherwise it should have sent a challenge. */
debug("Received RSA challenge from server.");
/* Ask the agent to decrypt the challenge. */
- if (!ssh_decrypt_challenge(auth, e, n, challenge,
- session_id, 1, response)) {
- /* The agent failed to authenticate this identifier although it
- advertised it supports this. Just return a wrong value. */
+ if (!ssh_decrypt_challenge(auth, key, challenge, session_id, 1, response)) {
+ /*
+ * The agent failed to authenticate this identifier
+ * although it advertised it supports this. Just
+ * return a wrong value.
+ */
log("Authentication agent failed to decrypt challenge.");
memset(response, 0, sizeof(response));
}
+ key_free(key);
debug("Sending response to RSA challenge.");
/* Send the decrypted challenge back to the server. */
/* The server returns success if it accepted the authentication. */
if (type == SSH_SMSG_SUCCESS) {
- debug("RSA authentication accepted by server.");
- BN_clear_free(e);
- BN_clear_free(n);
+ ssh_close_authentication_connection(auth);
BN_clear_free(challenge);
+ debug("RSA authentication accepted by server.");
return 1;
}
/* Otherwise it should return failure. */
packet_disconnect("Protocol error waiting RSA auth response: %d",
type);
}
-
- BN_clear_free(e);
- BN_clear_free(n);
+ ssh_close_authentication_connection(auth);
BN_clear_free(challenge);
-
debug("RSA authentication using agent refused.");
return 0;
}
void
respond_to_rsa_challenge(BIGNUM * challenge, RSA * prv)
{
- unsigned char buf[32], response[16];
+ u_char buf[32], response[16];
MD5_CTX md;
int i, len;
/* Decrypt the challenge using the private key. */
- rsa_private_decrypt(challenge, challenge, prv);
+ /* XXX think about Bleichenbacher, too */
+ if (rsa_private_decrypt(challenge, challenge, prv) <= 0)
+ packet_disconnect(
+ "respond_to_rsa_challenge: rsa_private_decrypt failed");
/* Compute the response. */
/* The response is MD5 of decrypted challenge plus session id. */
len = BN_num_bytes(challenge);
if (len <= 0 || len > sizeof(buf))
- packet_disconnect("respond_to_rsa_challenge: bad challenge length %d",
- len);
+ packet_disconnect(
+ "respond_to_rsa_challenge: bad challenge length %d", len);
memset(buf, 0, sizeof(buf));
BN_bn2bin(challenge, buf + sizeof(buf) - len);
int plen, clen;
/* Try to load identification for the authentication key. */
- public = key_new(KEY_RSA);
+ public = key_new(KEY_RSA1);
if (!load_public_key(authfile, public, &comment)) {
key_free(public);
/* Could not load it. Fail. */
debug("Received RSA challenge from server.");
- private = key_new(KEY_RSA);
+ private = key_new(KEY_RSA1);
/*
* Load the private key. Try first with empty passphrase; if it
* fails, ask for a passphrase.
/* Expect the server to reject it... */
packet_read_expect(&plen, SSH_SMSG_FAILURE);
xfree(comment);
+ key_free(private);
+ BN_clear_free(challenge);
return 0;
}
/* Destroy the passphrase. */
#ifdef KRB4
int
-try_kerberos_authentication()
+try_kerberos_authentication(void)
{
KTEXT_ST auth; /* Kerberos data */
char *reply;
if (stat(tkt_string(), &st) < 0)
return 0;
- strncpy(inst, (char *) krb_get_phost(get_canonical_hostname()), INST_SZ);
+ strncpy(inst, (char *) krb_get_phost(get_canonical_hostname(1)), INST_SZ);
- realm = (char *) krb_realmofhost(get_canonical_hostname());
+ realm = (char *) krb_realmofhost(get_canonical_hostname(1));
if (!realm) {
- debug("Kerberos V4: no realm for %s", get_canonical_hostname());
+ debug("Kerberos V4: no realm for %s", get_canonical_hostname(1));
return 0;
}
/* This can really be anything. */
debug("Kerberos V4 authentication accepted.");
/* Get server's response. */
- reply = packet_get_string((unsigned int *) &auth.length);
+ reply = packet_get_string((u_int *) &auth.length);
memcpy(auth.dat, reply, auth.length);
xfree(reply);
#ifdef AFS
int
-send_kerberos_tgt()
+send_kerberos_tgt(void)
{
CREDENTIALS *creds;
char pname[ANAME_SZ], pinst[INST_SZ], prealm[REALM_SZ];
debug("Kerberos V4 ticket expired: %s", TKT_FILE);
return 0;
}
- creds_to_radix(creds, (unsigned char *)buffer, sizeof buffer);
+ creds_to_radix(creds, (u_char *)buffer, sizeof buffer);
xfree(creds);
packet_start(SSH_CMSG_HAVE_KERBEROS_TGT);
p = buf;
/* Get secret token. */
- memcpy(&creds.ticket_st.length, p, sizeof(unsigned int));
+ memcpy(&creds.ticket_st.length, p, sizeof(u_int));
if (creds.ticket_st.length > MAX_KTXT_LEN)
break;
- p += sizeof(unsigned int);
+ p += sizeof(u_int);
memcpy(creds.ticket_st.dat, p, creds.ticket_st.length);
p += creds.ticket_st.length;
creds.pinst[0] = '\0';
/* Encode token, ship it off. */
- if (creds_to_radix(&creds, (unsigned char*) buffer, sizeof buffer) <= 0)
+ if (creds_to_radix(&creds, (u_char *) buffer, sizeof buffer) <= 0)
break;
packet_start(SSH_CMSG_HAVE_AFS_TOKEN);
packet_put_string(buffer, strlen(buffer));
* Note that the client code is not tied to s/key or TIS.
*/
int
-try_skey_authentication()
+try_challenge_reponse_authentication(void)
{
int type, i;
int payload_len;
- unsigned int clen;
+ u_int clen;
+ char prompt[1024];
char *challenge, *response;
- debug("Doing skey authentication.");
-
- /* request a challenge */
- packet_start(SSH_CMSG_AUTH_TIS);
- packet_send();
- packet_write_wait();
+ debug("Doing challenge reponse authentication.");
- type = packet_read(&payload_len);
- if (type != SSH_SMSG_FAILURE &&
- type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
- packet_disconnect("Protocol error: got %d in response "
- "to skey-auth", type);
- }
- if (type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
- debug("No challenge for skey authentication.");
- return 0;
- }
- challenge = packet_get_string(&clen);
- packet_integrity_check(payload_len, (4 + clen), type);
- if (options.cipher == SSH_CIPHER_NONE)
- log("WARNING: Encryption is disabled! "
- "Reponse will be transmitted in clear text.");
- fprintf(stderr, "%s\n", challenge);
- xfree(challenge);
- fflush(stderr);
for (i = 0; i < options.number_of_password_prompts; i++) {
+ /* request a challenge */
+ packet_start(SSH_CMSG_AUTH_TIS);
+ packet_send();
+ packet_write_wait();
+
+ type = packet_read(&payload_len);
+ if (type != SSH_SMSG_FAILURE &&
+ type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
+ packet_disconnect("Protocol error: got %d in response "
+ "to SSH_CMSG_AUTH_TIS", type);
+ }
+ if (type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
+ debug("No challenge.");
+ return 0;
+ }
+ challenge = packet_get_string(&clen);
+ packet_integrity_check(payload_len, (4 + clen), type);
+ snprintf(prompt, sizeof prompt, "%s%s", challenge,
+ strchr(challenge, '\n') ? "" : "\nResponse: ");
+ xfree(challenge);
if (i != 0)
error("Permission denied, please try again.");
- response = read_passphrase("Response: ", 0);
+ if (options.cipher == SSH_CIPHER_NONE)
+ log("WARNING: Encryption is disabled! "
+ "Reponse will be transmitted in clear text.");
+ response = read_passphrase(prompt, 0);
+ if (strcmp(response, "") == 0) {
+ xfree(response);
+ break;
+ }
packet_start(SSH_CMSG_AUTH_TIS_RESPONSE);
- packet_put_string(response, strlen(response));
+ ssh_put_password(response);
memset(response, 0, strlen(response));
xfree(response);
packet_send();
return 1;
if (type != SSH_SMSG_FAILURE)
packet_disconnect("Protocol error: got %d in response "
- "to skey-auth-reponse", type);
+ "to SSH_CMSG_AUTH_TIS_RESPONSE", type);
}
/* failure */
return 0;
error("Permission denied, please try again.");
password = read_passphrase(prompt, 0);
packet_start(SSH_CMSG_AUTH_PASSWORD);
- packet_put_string(password, strlen(password));
+ ssh_put_password(password);
memset(password, 0, strlen(password));
xfree(password);
packet_send();
Key k;
int bits, rbits;
int ssh_cipher_default = SSH_CIPHER_3DES;
- unsigned char session_key[SSH_SESSION_KEY_LENGTH];
- unsigned char cookie[8];
- unsigned int supported_ciphers;
- unsigned int server_flags, client_flags;
+ u_char session_key[SSH_SESSION_KEY_LENGTH];
+ u_char cookie[8];
+ u_int supported_ciphers;
+ u_int server_flags, client_flags;
int payload_len, clen, sum_len = 0;
u_int32_t rand = 0;
packet_integrity_check(payload_len,
8 + 4 + sum_len + 0 + 4 + 0 + 0 + 4 + 4 + 4,
SSH_SMSG_PUBLIC_KEY);
- k.type = KEY_RSA;
+ k.type = KEY_RSA1;
k.rsa = host_key;
check_host_key(host, hostaddr, &k,
options.user_hostfile, options.system_hostfile);
RSA_free(public_key);
RSA_free(host_key);
- if (options.cipher == SSH_CIPHER_ILLEGAL) {
- log("No valid SSH1 cipher, using %.100s instead.",
- cipher_name(SSH_FALLBACK_CIPHER));
- options.cipher = SSH_FALLBACK_CIPHER;
- } else if (options.cipher == SSH_CIPHER_NOT_SET) {
- if (cipher_mask1() & supported_ciphers & (1 << ssh_cipher_default))
+ if (options.cipher == SSH_CIPHER_NOT_SET) {
+ if (cipher_mask_ssh1(1) & supported_ciphers & (1 << ssh_cipher_default))
options.cipher = ssh_cipher_default;
- else {
- debug("Cipher %s not supported, using %.100s instead.",
- cipher_name(ssh_cipher_default),
- cipher_name(SSH_FALLBACK_CIPHER));
- options.cipher = SSH_FALLBACK_CIPHER;
- }
+ } else if (options.cipher == SSH_CIPHER_ILLEGAL ||
+ !(cipher_mask_ssh1(1) & (1 << options.cipher))) {
+ log("No valid SSH1 cipher, using %.100s instead.",
+ cipher_name(ssh_cipher_default));
+ options.cipher = ssh_cipher_default;
}
/* Check that the selected cipher is supported. */
if (!(supported_ciphers & (1 << options.cipher)))
*/
void
ssh_userauth(
- const char* local_user,
- const char* server_user,
+ const char *local_user,
+ const char *server_user,
char *host,
int host_key_valid, RSA *own_host_key)
{
/* Try RSA authentication for each identity. */
for (i = 0; i < options.num_identity_files; i++)
- if (try_rsa_authentication(options.identity_files[i]))
+ if (options.identity_files_type[i] == KEY_RSA1 &&
+ try_rsa_authentication(options.identity_files[i]))
return;
}
- /* Try skey authentication if the server supports it. */
+ /* Try challenge response authentication if the server supports it. */
if ((supported_authentications & (1 << SSH_AUTH_TIS)) &&
- options.skey_authentication && !options.batch_mode) {
- if (try_skey_authentication())
+ options.challenge_reponse_authentication && !options.batch_mode) {
+ if (try_challenge_reponse_authentication())
return;
}
/* Try password authentication if the server supports it. */
options.password_authentication && !options.batch_mode) {
char prompt[80];
- snprintf(prompt, sizeof(prompt), "%.30s@%.40s's password: ",
+ snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
server_user, host);
if (try_password_authentication(prompt))
return;
andersk / openssh.git / blobdiff