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-rw-r--r--crypto/openssh/auth2.c472
1 files changed, 0 insertions, 472 deletions
diff --git a/crypto/openssh/auth2.c b/crypto/openssh/auth2.c
deleted file mode 100644
index a663eca2b8928..0000000000000
--- a/crypto/openssh/auth2.c
+++ /dev/null
@@ -1,472 +0,0 @@
-/*
- * Copyright (c) 2000 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.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by Markus Friedl.
- * 4. The name of the author may not be used to endorse or promote products
- * derived from this software without specific prior written permission.
- *
- * 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.
- *
- * $FreeBSD$
- */
-#include "includes.h"
-RCSID("$OpenBSD: auth2.c,v 1.8 2000/05/08 17:42:24 markus Exp $");
-
-#include <openssl/dsa.h>
-#include <openssl/rsa.h>
-#include <openssl/evp.h>
-
-#include "xmalloc.h"
-#include "rsa.h"
-#include "ssh.h"
-#include "pty.h"
-#include "packet.h"
-#include "buffer.h"
-#include "cipher.h"
-#include "servconf.h"
-#include "compat.h"
-#include "channels.h"
-#include "bufaux.h"
-#include "ssh2.h"
-#include "auth.h"
-#include "session.h"
-#include "dispatch.h"
-#include "auth.h"
-#include "key.h"
-#include "kex.h"
-
-#include "dsa.h"
-#include "uidswap.h"
-
-/* import */
-extern ServerOptions options;
-extern unsigned char *session_id2;
-extern int session_id2_len;
-
-/* protocol */
-
-void input_service_request(int type, int plen);
-void input_userauth_request(int type, int plen);
-void protocol_error(int type, int plen);
-
-/* auth */
-int ssh2_auth_none(struct passwd *pw);
-int ssh2_auth_password(struct passwd *pw);
-int ssh2_auth_pubkey(struct passwd *pw, unsigned char *raw, unsigned int rlen);
-
-/* helper */
-struct passwd* auth_set_user(char *u, char *s);
-int user_dsa_key_allowed(struct passwd *pw, Key *key);
-
-typedef struct Authctxt Authctxt;
-struct Authctxt {
- char *user;
- char *service;
- struct passwd pw;
- int valid;
-};
-static Authctxt *authctxt = NULL;
-static int userauth_success = 0;
-
-/*
- * loop until userauth_success == TRUE
- */
-
-void
-do_authentication2()
-{
- /* turn off skey/kerberos, not supported by SSH2 */
-#ifdef SKEY
- options.skey_authentication = 0;
-#endif
-#ifdef KRB4
- options.krb4_authentication = 0;
-#endif
-
- dispatch_init(&protocol_error);
- dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
- dispatch_run(DISPATCH_BLOCK, &userauth_success);
- do_authenticated2();
-}
-
-void
-protocol_error(int type, int plen)
-{
- log("auth: protocol error: type %d plen %d", type, plen);
- packet_start(SSH2_MSG_UNIMPLEMENTED);
- packet_put_int(0);
- packet_send();
- packet_write_wait();
-}
-
-void
-input_service_request(int type, int plen)
-{
- unsigned int len;
- int accept = 0;
- char *service = packet_get_string(&len);
- packet_done();
-
- if (strcmp(service, "ssh-userauth") == 0) {
- if (!userauth_success) {
- accept = 1;
- /* now we can handle user-auth requests */
- dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
- }
- }
- /* XXX all other service requests are denied */
-
- if (accept) {
- packet_start(SSH2_MSG_SERVICE_ACCEPT);
- packet_put_cstring(service);
- packet_send();
- packet_write_wait();
- } else {
- debug("bad service request %s", service);
- packet_disconnect("bad service request %s", service);
- }
- xfree(service);
-}
-
-void
-input_userauth_request(int type, int plen)
-{
- static void (*authlog) (const char *fmt,...) = verbose;
- static int attempt = 0;
- unsigned int len, rlen;
- int authenticated = 0;
- char *raw, *user, *service, *method, *authmsg = NULL;
- struct passwd *pw;
-
- if (++attempt == AUTH_FAIL_MAX)
- packet_disconnect("too many failed userauth_requests");
-
- raw = packet_get_raw(&rlen);
- if (plen != rlen)
- fatal("plen != rlen");
- user = packet_get_string(&len);
- service = packet_get_string(&len);
- method = packet_get_string(&len);
- debug("userauth-request for user %s service %s method %s", user, service, method);
-
- /* XXX we only allow the ssh-connection service */
- pw = auth_set_user(user, service);
- if (pw && strcmp(service, "ssh-connection")==0) {
- if (strcmp(method, "none") == 0) {
- authenticated = ssh2_auth_none(pw);
- } else if (strcmp(method, "password") == 0) {
- authenticated = ssh2_auth_password(pw);
- } else if (strcmp(method, "publickey") == 0) {
- authenticated = ssh2_auth_pubkey(pw, raw, rlen);
- }
- }
- if (authenticated && pw && pw->pw_uid == 0 && !options.permit_root_login) {
- authenticated = 0;
- log("ROOT LOGIN REFUSED FROM %.200s",
- get_canonical_hostname());
- }
-
- /* Raise logging level */
- if (authenticated == 1 ||
- attempt == AUTH_FAIL_LOG ||
- strcmp(method, "password") == 0)
- authlog = log;
-
- /* Log before sending the reply */
- if (authenticated == 1) {
- authmsg = "Accepted";
- } else if (authenticated == 0) {
- authmsg = "Failed";
- } else {
- authmsg = "Postponed";
- }
- authlog("%s %s for %.200s from %.200s port %d ssh2",
- authmsg,
- method,
- pw && pw->pw_uid == 0 ? "ROOT" : user,
- get_remote_ipaddr(),
- get_remote_port());
-
- /* XXX todo: check if multiple auth methods are needed */
- if (authenticated == 1) {
- /* turn off userauth */
- dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &protocol_error);
- packet_start(SSH2_MSG_USERAUTH_SUCCESS);
- packet_send();
- packet_write_wait();
- /* now we can break out */
- userauth_success = 1;
- } else if (authenticated == 0) {
- packet_start(SSH2_MSG_USERAUTH_FAILURE);
- packet_put_cstring("publickey,password"); /* XXX dynamic */
- packet_put_char(0); /* XXX partial success, unused */
- packet_send();
- packet_write_wait();
- }
-
- xfree(service);
- xfree(user);
- xfree(method);
-}
-
-int
-ssh2_auth_none(struct passwd *pw)
-{
- packet_done();
- return auth_password(pw, "");
-}
-int
-ssh2_auth_password(struct passwd *pw)
-{
- char *password;
- int authenticated = 0;
- int change;
- unsigned int len;
- change = packet_get_char();
- if (change)
- log("password change not supported");
- password = packet_get_string(&len);
- packet_done();
- if (options.password_authentication &&
- auth_password(pw, password) == 1)
- authenticated = 1;
- memset(password, 0, len);
- xfree(password);
- return authenticated;
-}
-int
-ssh2_auth_pubkey(struct passwd *pw, unsigned char *raw, unsigned int rlen)
-{
- Buffer b;
- Key *key;
- char *pkalg, *pkblob, *sig;
- unsigned int alen, blen, slen;
- int have_sig;
- int authenticated = 0;
-
- if (options.dsa_authentication == 0) {
- debug("pubkey auth disabled");
- return 0;
- }
- if (datafellows & SSH_BUG_PUBKEYAUTH) {
- log("bug compatibility with ssh-2.0.13 pubkey not implemented");
- return 0;
- }
- have_sig = packet_get_char();
- pkalg = packet_get_string(&alen);
- if (strcmp(pkalg, KEX_DSS) != 0) {
- xfree(pkalg);
- log("bad pkalg %s", pkalg); /*XXX*/
- return 0;
- }
- pkblob = packet_get_string(&blen);
- key = dsa_key_from_blob(pkblob, blen);
- if (key != NULL) {
- if (have_sig) {
- sig = packet_get_string(&slen);
- packet_done();
- buffer_init(&b);
- buffer_append(&b, session_id2, session_id2_len);
- buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
- if (slen + 4 > rlen)
- fatal("bad rlen/slen");
- buffer_append(&b, raw, rlen - slen - 4);
-#ifdef DEBUG_DSS
- buffer_dump(&b);
-#endif
- /* test for correct signature */
- if (user_dsa_key_allowed(pw, key) &&
- dsa_verify(key, sig, slen, buffer_ptr(&b), buffer_len(&b)) == 1)
- authenticated = 1;
- buffer_clear(&b);
- xfree(sig);
- } else {
- packet_done();
- debug("test key...");
- /* test whether pkalg/pkblob are acceptable */
- /* XXX fake reply and always send PK_OK ? */
- /*
- * XXX this allows testing whether a user is allowed
- * to login: if you happen to have a valid pubkey this
- * message is sent. the message is NEVER sent at all
- * if a user is not allowed to login. is this an
- * issue? -markus
- */
- if (user_dsa_key_allowed(pw, key)) {
- packet_start(SSH2_MSG_USERAUTH_PK_OK);
- packet_put_string(pkalg, alen);
- packet_put_string(pkblob, blen);
- packet_send();
- packet_write_wait();
- authenticated = -1;
- }
- }
- key_free(key);
- }
- xfree(pkalg);
- xfree(pkblob);
- return authenticated;
-}
-
-/* set and get current user */
-
-struct passwd*
-auth_get_user(void)
-{
- return (authctxt != NULL && authctxt->valid) ? &authctxt->pw : NULL;
-}
-
-struct passwd*
-auth_set_user(char *u, char *s)
-{
- struct passwd *pw, *copy;
-
- if (authctxt == NULL) {
- authctxt = xmalloc(sizeof(*authctxt));
- authctxt->valid = 0;
- authctxt->user = xstrdup(u);
- authctxt->service = xstrdup(s);
- setproctitle("%s", u);
- pw = getpwnam(u);
- if (!pw || !allowed_user(pw)) {
- log("auth_set_user: illegal user %s", u);
- return NULL;
- }
- copy = &authctxt->pw;
- memset(copy, 0, sizeof(*copy));
- copy->pw_name = xstrdup(pw->pw_name);
- copy->pw_passwd = xstrdup(pw->pw_passwd);
- copy->pw_uid = pw->pw_uid;
- copy->pw_gid = pw->pw_gid;
- copy->pw_dir = xstrdup(pw->pw_dir);
- copy->pw_shell = xstrdup(pw->pw_shell);
- copy->pw_class = xstrdup(pw->pw_class);
- copy->pw_expire = pw->pw_expire;
- copy->pw_change = pw->pw_change;
- authctxt->valid = 1;
- } else {
- if (strcmp(u, authctxt->user) != 0 ||
- strcmp(s, authctxt->service) != 0) {
- log("auth_set_user: missmatch: (%s,%s)!=(%s,%s)",
- u, s, authctxt->user, authctxt->service);
- return NULL;
- }
- }
- return auth_get_user();
-}
-
-/* return 1 if user allows given key */
-int
-user_dsa_key_allowed(struct passwd *pw, Key *key)
-{
- char line[8192], file[1024];
- int found_key = 0;
- unsigned int bits = -1;
- FILE *f;
- unsigned long linenum = 0;
- struct stat st;
- Key *found;
-
- /* Temporarily use the user's uid. */
- temporarily_use_uid(pw->pw_uid);
-
- /* The authorized keys. */
- snprintf(file, sizeof file, "%.500s/%.100s", pw->pw_dir,
- SSH_USER_PERMITTED_KEYS2);
-
- /* Fail quietly if file does not exist */
- if (stat(file, &st) < 0) {
- /* Restore the privileged uid. */
- restore_uid();
- return 0;
- }
- /* Open the file containing the authorized keys. */
- f = fopen(file, "r");
- if (!f) {
- /* Restore the privileged uid. */
- restore_uid();
- return 0;
- }
- if (options.strict_modes) {
- int fail = 0;
- char buf[1024];
- /* Check open file in order to avoid open/stat races */
- if (fstat(fileno(f), &st) < 0 ||
- (st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
- (st.st_mode & 022) != 0) {
- snprintf(buf, sizeof buf, "DSA authentication refused for %.100s: "
- "bad ownership or modes for '%s'.", pw->pw_name, file);
- fail = 1;
- } else {
- /* Check path to SSH_USER_PERMITTED_KEYS */
- int i;
- static const char *check[] = {
- "", SSH_USER_DIR, NULL
- };
- for (i = 0; check[i]; i++) {
- snprintf(line, sizeof line, "%.500s/%.100s",
- pw->pw_dir, check[i]);
- if (stat(line, &st) < 0 ||
- (st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
- (st.st_mode & 022) != 0) {
- snprintf(buf, sizeof buf,
- "DSA authentication refused for %.100s: "
- "bad ownership or modes for '%s'.",
- pw->pw_name, line);
- fail = 1;
- break;
- }
- }
- }
- if (fail) {
- log(buf);
- fclose(f);
- restore_uid();
- return 0;
- }
- }
- found_key = 0;
- found = key_new(KEY_DSA);
-
- while (fgets(line, sizeof(line), f)) {
- char *cp;
- linenum++;
- /* Skip leading whitespace, empty and comment lines. */
- for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
- ;
- if (!*cp || *cp == '\n' || *cp == '#')
- continue;
- bits = key_read(found, &cp);
- if (bits == 0)
- continue;
- if (key_equal(found, key)) {
- found_key = 1;
- debug("matching key found: file %s, line %ld",
- file, linenum);
- break;
- }
- }
- restore_uid();
- fclose(f);
- key_free(found);
- return found_key;
-}
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