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-rw-r--r--usr/src/cmd/ssh/sshd/auth2-pubkey.c359
1 files changed, 0 insertions, 359 deletions
diff --git a/usr/src/cmd/ssh/sshd/auth2-pubkey.c b/usr/src/cmd/ssh/sshd/auth2-pubkey.c
deleted file mode 100644
index 658634c195..0000000000
--- a/usr/src/cmd/ssh/sshd/auth2-pubkey.c
+++ /dev/null
@@ -1,359 +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.
- *
- * 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.
- */
-/*
- * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
- * Use is subject to license terms.
- */
-
-#include "includes.h"
-RCSID("$OpenBSD: auth2-pubkey.c,v 1.2 2002/05/31 11:35:15 markus Exp $");
-
-#include "ssh2.h"
-#include "xmalloc.h"
-#include "packet.h"
-#include "buffer.h"
-#include "log.h"
-#include "servconf.h"
-#include "compat.h"
-#include "bufaux.h"
-#include "auth.h"
-#include "key.h"
-#include "pathnames.h"
-#include "uidswap.h"
-#include "auth-options.h"
-#include "canohost.h"
-
-#ifdef USE_PAM
-#include <security/pam_appl.h>
-#include "auth-pam.h"
-#endif /* USE_PAM */
-
-/* import */
-extern ServerOptions options;
-extern u_char *session_id2;
-extern int session_id2_len;
-
-static void
-userauth_pubkey(Authctxt *authctxt)
-{
- Buffer b;
- Key *key = NULL;
- char *pkalg;
- u_char *pkblob, *sig;
- u_int alen, blen, slen;
- int have_sig, pktype;
- int authenticated = 0;
-
- if (!authctxt || !authctxt->method)
- fatal("%s: missing context", __func__);
-
- have_sig = packet_get_char();
- if (datafellows & SSH_BUG_PKAUTH) {
- debug2("userauth_pubkey: SSH_BUG_PKAUTH");
- /* no explicit pkalg given */
- pkblob = packet_get_string(&blen);
- buffer_init(&b);
- buffer_append(&b, pkblob, blen);
- /* so we have to extract the pkalg from the pkblob */
- pkalg = buffer_get_string(&b, &alen);
- buffer_free(&b);
- } else {
- pkalg = packet_get_string(&alen);
- pkblob = packet_get_string(&blen);
- }
- pktype = key_type_from_name(pkalg);
- if (pktype == KEY_UNSPEC) {
- /* this is perfectly legal */
- log("userauth_pubkey: unsupported public key algorithm: %s",
- pkalg);
- goto done;
- }
- key = key_from_blob(pkblob, blen);
- if (key == NULL) {
- error("userauth_pubkey: cannot decode key: %s", pkalg);
- goto done;
- }
- if (key->type != pktype) {
- error("userauth_pubkey: type mismatch for decoded key "
- "(received %d, expected %d)", key->type, pktype);
- goto done;
- }
-
- /* Detect and count abandonment */
- if (authctxt->method->method_data) {
- Key *prev_key;
- unsigned char *prev_pkblob;
- int prev_blen;
-
- /*
- * Check for earlier test of a key that was allowed but
- * not followed up with a pubkey req for the same pubkey
- * and with a signature.
- */
- prev_key = authctxt->method->method_data;
- if ((prev_blen = key_to_blob(prev_key,
- &prev_pkblob, NULL))) {
- if (prev_blen != blen ||
- memcmp(prev_pkblob, pkblob, blen) != 0) {
- authctxt->method->abandons++;
- authctxt->method->attempts++;
- }
- }
- key_free(prev_key);
- authctxt->method->method_data = NULL;
- }
-
- if (have_sig) {
- sig = packet_get_string(&slen);
- packet_check_eom();
- buffer_init(&b);
- if (datafellows & SSH_OLD_SESSIONID) {
- buffer_append(&b, session_id2, session_id2_len);
- } else {
- buffer_put_string(&b, session_id2, session_id2_len);
- }
- /* reconstruct packet */
- buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
- buffer_put_cstring(&b, authctxt->user);
- buffer_put_cstring(&b,
- datafellows & SSH_BUG_PKSERVICE ?
- "ssh-userauth" :
- authctxt->service);
- if (datafellows & SSH_BUG_PKAUTH) {
- buffer_put_char(&b, have_sig);
- } else {
- buffer_put_cstring(&b, "publickey");
- buffer_put_char(&b, have_sig);
- buffer_put_cstring(&b, pkalg);
- }
- buffer_put_string(&b, pkblob, blen);
-#ifdef DEBUG_PK
- buffer_dump(&b);
-#endif
- /* test for correct signature */
- if (user_key_allowed(authctxt->pw, key) &&
- key_verify(key, sig, slen, buffer_ptr(&b),
- buffer_len(&b)) == 1) {
- authenticated = 1;
- }
- authctxt->method->postponed = 0;
- buffer_free(&b);
- xfree(sig);
- } else {
- debug("test whether pkalg/pkblob are acceptable");
- packet_check_eom();
-
- /* 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_key_allowed(authctxt->pw, key)) {
- packet_start(SSH2_MSG_USERAUTH_PK_OK);
- packet_put_string(pkalg, alen);
- packet_put_string(pkblob, blen);
- packet_send();
- packet_write_wait();
- authctxt->method->postponed = 1;
- /*
- * Remember key that was tried so we can
- * correctly detect abandonment. See above.
- */
- authctxt->method->method_data = (void *) key;
- key = NULL;
- }
- }
- if (authenticated != 1)
- auth_clear_options();
-
-done:
- /*
- * XXX TODO: add config options for specifying users for whom
- * this userauth is insufficient and what userauths may
- * continue.
- */
-#ifdef USE_PAM
- if (authenticated) {
- if (!do_pam_non_initial_userauth(authctxt))
- authenticated = 0;
- }
-#endif /* USE_PAM */
-
- debug2("userauth_pubkey: authenticated %d pkalg %s", authenticated, pkalg);
- if (key != NULL)
- key_free(key);
- xfree(pkalg);
- xfree(pkblob);
-#ifdef HAVE_CYGWIN
- if (check_nt_auth(0, authctxt->pw) == 0)
- return;
-#endif
- if (authenticated)
- authctxt->method->authenticated = 1;
-}
-
-/* return 1 if user allows given key */
-static int
-user_key_allowed2(struct passwd *pw, Key *key, char *file)
-{
- char line[8192];
- int found_key = 0;
- FILE *f;
- u_long linenum = 0;
- struct stat st;
- Key *found;
- char *fp;
-
- if (pw == NULL)
- return 0;
-
- /* Temporarily use the user's uid. */
- temporarily_use_uid(pw);
-
- debug("trying public key file %s", file);
-
- /* 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 &&
- secure_filename(f, file, pw, line, sizeof(line)) != 0) {
- (void) fclose(f);
- log("Authentication refused: %s", line);
- restore_uid();
- return 0;
- }
-
- found_key = 0;
- found = key_new(key->type);
-
- while (fgets(line, sizeof(line), f)) {
- char *cp, *options = NULL;
- linenum++;
- /* Skip leading whitespace, empty and comment lines. */
- for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
- ;
- if (!*cp || *cp == '\n' || *cp == '#')
- continue;
-
- if (key_read(found, &cp) != 1) {
- /* no key? check if there are options for this key */
- int quoted = 0;
- debug2("user_key_allowed: check options: '%s'", cp);
- options = cp;
- for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
- if (*cp == '\\' && cp[1] == '"')
- cp++; /* Skip both */
- else if (*cp == '"')
- quoted = !quoted;
- }
- /* Skip remaining whitespace. */
- for (; *cp == ' ' || *cp == '\t'; cp++)
- ;
- if (key_read(found, &cp) != 1) {
- debug2("user_key_allowed: advance: '%s'", cp);
- /* still no key? advance to next line*/
- continue;
- }
- }
- if (key_equal(found, key) &&
- auth_parse_options(pw, options, file, linenum) == 1) {
- found_key = 1;
- debug("matching key found: file %s, line %lu",
- file, linenum);
- fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
- verbose("Found matching %s key: %s",
- key_type(found), fp);
- xfree(fp);
- break;
- }
- }
- restore_uid();
- (void) fclose(f);
- key_free(found);
- if (!found_key)
- debug2("key not found");
- return found_key;
-}
-
-/* check whether given key is in .ssh/authorized_keys* */
-int
-user_key_allowed(struct passwd *pw, Key *key)
-{
- int success;
- char *file;
-
- if (pw == NULL)
- return 0;
-
- file = authorized_keys_file(pw);
- success = user_key_allowed2(pw, key, file);
- xfree(file);
- if (success)
- return success;
-
- /* try suffix "2" for backward compat, too */
- file = authorized_keys_file2(pw);
- success = user_key_allowed2(pw, key, file);
- xfree(file);
- return success;
-}
-
-static
-void
-userauth_pubkey_abandon(Authctxt *authctxt, Authmethod *method)
-{
- if (!authctxt || !method)
- return;
-
- if (method->method_data) {
- method->abandons++;
- method->attempts++;
- key_free((Key *) method->method_data);
- method->method_data = NULL;
- }
-}
-
-Authmethod method_pubkey = {
- "publickey",
- &options.pubkey_authentication,
- userauth_pubkey,
- userauth_pubkey_abandon,
- NULL, NULL, /* method data and hist data */
- 0, /* not initial userauth */
- 0, 0, 0, /* counters */
- 0, 0, 0, 0, 0, 0 /* state */
-};