diff options
Diffstat (limited to 'crypto/openssh/auth2-pubkey.c')
| -rw-r--r-- | crypto/openssh/auth2-pubkey.c | 292 |
1 files changed, 0 insertions, 292 deletions
diff --git a/crypto/openssh/auth2-pubkey.c b/crypto/openssh/auth2-pubkey.c deleted file mode 100644 index 9863cd9..0000000 --- a/crypto/openssh/auth2-pubkey.c +++ /dev/null @@ -1,292 +0,0 @@ -/* $OpenBSD: auth2-pubkey.c,v 1.15 2006/08/03 03:34:41 deraadt Exp $ */ -/* - * 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. - */ - -#include "includes.h" - -#include <sys/types.h> -#include <sys/stat.h> - -#include <pwd.h> -#include <stdio.h> -#include <stdarg.h> - -#include "xmalloc.h" -#include "ssh.h" -#include "ssh2.h" -#include "packet.h" -#include "buffer.h" -#include "log.h" -#include "servconf.h" -#include "compat.h" -#include "key.h" -#include "hostfile.h" -#include "auth.h" -#include "pathnames.h" -#include "uidswap.h" -#include "auth-options.h" -#include "canohost.h" -#ifdef GSSAPI -#include "ssh-gss.h" -#endif -#include "monitor_wrap.h" -#include "misc.h" - -/* import */ -extern ServerOptions options; -extern u_char *session_id2; -extern u_int session_id2_len; - -static int -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->valid) { - debug2("userauth_pubkey: disabled because of invalid user"); - return 0; - } - 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 */ - logit("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; - } - 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 */ - authenticated = 0; - if (PRIVSEP(user_key_allowed(authctxt->pw, key)) && - PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b), - buffer_len(&b))) == 1) - authenticated = 1; - 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 (PRIVSEP(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->postponed = 1; - } - } - if (authenticated != 1) - auth_clear_options(); -done: - 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) - authenticated = 0; -#endif - return authenticated; -} - -/* return 1 if user allows given key */ -static int -user_key_allowed2(struct passwd *pw, Key *key, char *file) -{ - char line[SSH_MAX_PUBKEY_BYTES]; - int found_key = 0; - FILE *f; - u_long linenum = 0; - struct stat st; - Key *found; - char *fp; - - /* 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) { - fclose(f); - logit("Authentication refused: %s", line); - restore_uid(); - return 0; - } - - found_key = 0; - found = key_new(key->type); - - while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) { - char *cp, *key_options = NULL; - - /* 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); - key_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, key_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(); - 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; - - 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; -} - -Authmethod method_pubkey = { - "publickey", - userauth_pubkey, - &options.pubkey_authentication -}; |
