=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/Attic/auth1.c,v retrieving revision 1.2 retrieving revision 1.2.2.3 diff -u -r1.2 -r1.2.2.3 --- src/usr.bin/ssh/Attic/auth1.c 2000/04/29 18:11:52 1.2 +++ src/usr.bin/ssh/Attic/auth1.c 2000/11/10 20:49:29 1.2.2.3 @@ -1,17 +1,22 @@ /* * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland * All rights reserved + * + * 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: auth1.c,v 1.2 2000/04/29 18:11:52 markus Exp $"); +RCSID("$OpenBSD: auth1.c,v 1.2.2.3 2000/11/10 20:49:29 jason Exp $"); #include "xmalloc.h" #include "rsa.h" #include "ssh.h" #include "packet.h" #include "buffer.h" -#include "cipher.h" #include "mpaux.h" #include "servconf.h" #include "compat.h" @@ -52,79 +57,17 @@ } /* - * The user does not exist or access is denied, - * but fake indication that authentication is needed. + * read packets and try to authenticate local user 'luser'. + * return if authentication is successfull. not that pw == NULL + * if the user does not exists or is not allowed to login. + * each auth method has to 'fake' authentication for nonexisting + * users. */ void -do_fake_authloop1(char *user) +do_authloop(struct passwd * pw, char *luser) { + int authenticated = 0; int attempt = 0; - - log("Faking authloop for illegal user %.200s from %.200s port %d", - user, - get_remote_ipaddr(), - get_remote_port()); - - /* Indicate that authentication is needed. */ - packet_start(SSH_SMSG_FAILURE); - packet_send(); - packet_write_wait(); - - /* - * Keep reading packets, and always respond with a failure. This is - * to avoid disclosing whether such a user really exists. - */ - for (attempt = 1;; attempt++) { - /* Read a packet. This will not return if the client disconnects. */ - int plen; - int type = packet_read(&plen); -#ifdef SKEY - unsigned int dlen; - char *password, *skeyinfo; - password = NULL; - /* Try to send a fake s/key challenge. */ - if (options.skey_authentication == 1 && - (skeyinfo = skey_fake_keyinfo(user)) != NULL) { - if (type == SSH_CMSG_AUTH_TIS) { - packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE); - packet_put_string(skeyinfo, strlen(skeyinfo)); - packet_send(); - packet_write_wait(); - continue; - } else if (type == SSH_CMSG_AUTH_PASSWORD && - options.password_authentication && - (password = packet_get_string(&dlen)) != NULL && - dlen == 5 && - strncasecmp(password, "s/key", 5) == 0 ) { - packet_send_debug(skeyinfo); - } - } - if (password != NULL) - xfree(password); -#endif - if (attempt > AUTH_FAIL_MAX) - packet_disconnect(AUTH_FAIL_MSG, user); - - /* - * Send failure. This should be indistinguishable from a - * failed authentication. - */ - packet_start(SSH_SMSG_FAILURE); - packet_send(); - packet_write_wait(); - } - /* NOTREACHED */ - abort(); -} - -/* - * read packets and try to authenticate local user *pw. - * return if authentication is successfull - */ -void -do_authloop(struct passwd * pw) -{ - int attempt = 0; unsigned int bits; RSA *client_host_key; BIGNUM *n; @@ -142,7 +85,9 @@ packet_write_wait(); for (attempt = 1;; attempt++) { - int authenticated = 0; + /* default to fail */ + authenticated = 0; + strlcpy(user, "", sizeof user); /* Get a packet from the client. */ @@ -153,7 +98,6 @@ #ifdef AFS case SSH_CMSG_HAVE_KERBEROS_TGT: if (!options.kerberos_tgt_passing) { - /* packet_get_all(); */ verbose("Kerberos tgt passing disabled."); break; } else { @@ -161,14 +105,13 @@ char *tgt = packet_get_string(&dlen); packet_integrity_check(plen, 4 + dlen, type); if (!auth_kerberos_tgt(pw, tgt)) - verbose("Kerberos tgt REFUSED for %s", pw->pw_name); + verbose("Kerberos tgt REFUSED for %.100s", luser); xfree(tgt); } continue; case SSH_CMSG_HAVE_AFS_TOKEN: if (!options.afs_token_passing || !k_hasafs()) { - /* packet_get_all(); */ verbose("AFS token passing disabled."); break; } else { @@ -176,7 +119,7 @@ char *token_string = packet_get_string(&dlen); packet_integrity_check(plen, 4 + dlen, type); if (!auth_afs_token(pw, token_string)) - verbose("AFS token REFUSED for %s", pw->pw_name); + verbose("AFS token REFUSED for %.100s", luser); xfree(token_string); } continue; @@ -198,11 +141,12 @@ memcpy(auth.dat, kdata, auth.length); xfree(kdata); - authenticated = auth_krb4(pw->pw_name, &auth, &tkt_user); - - if (authenticated) { - snprintf(user, sizeof user, " tktuser %s", tkt_user); - xfree(tkt_user); + if (pw != NULL) { + authenticated = auth_krb4(pw->pw_name, &auth, &tkt_user); + if (authenticated) { + snprintf(user, sizeof user, " tktuser %s", tkt_user); + xfree(tkt_user); + } } } break; @@ -222,8 +166,7 @@ client_user = packet_get_string(&ulen); packet_integrity_check(plen, 4 + ulen, type); - /* Try to authenticate using /etc/hosts.equiv and - .rhosts. */ + /* Try to authenticate using /etc/hosts.equiv and .rhosts. */ authenticated = auth_rhosts(pw, client_user); snprintf(user, sizeof user, " ruser %s", client_user); @@ -255,7 +198,7 @@ packet_get_bignum(client_host_key->n, &nlen); if (bits != BN_num_bits(client_host_key->n)) - log("Warning: keysize mismatch for client_host_key: " + verbose("Warning: keysize mismatch for client_host_key: " "actual %d, announced %d", BN_num_bits(client_host_key->n), bits); packet_integrity_check(plen, (4 + ulen) + 4 + elen + nlen, type); @@ -303,16 +246,18 @@ case SSH_CMSG_AUTH_TIS: debug("rcvd SSH_CMSG_AUTH_TIS"); if (options.skey_authentication == 1) { - char *skeyinfo = skey_keyinfo(pw->pw_name); + char *skeyinfo = NULL; + if (pw != NULL) + skeyinfo = skey_keyinfo(pw->pw_name); if (skeyinfo == NULL) { - debug("generating fake skeyinfo for %.100s.", pw->pw_name); - skeyinfo = skey_fake_keyinfo(pw->pw_name); + debug("generating fake skeyinfo for %.100s.", luser); + skeyinfo = skey_fake_keyinfo(luser); } if (skeyinfo != NULL) { /* we send our s/key- in tis-challenge messages */ debug("sending challenge '%s'", skeyinfo); packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE); - packet_put_string(skeyinfo, strlen(skeyinfo)); + packet_put_cstring(skeyinfo); packet_send(); packet_write_wait(); continue; @@ -325,8 +270,9 @@ char *response = packet_get_string(&dlen); debug("skey response == '%s'", response); packet_integrity_check(plen, 4 + dlen, type); - authenticated = (skey_haskey(pw->pw_name) == 0 && - skey_passcheck(pw->pw_name, response) != -1); + authenticated = (pw != NULL && + skey_haskey(pw->pw_name) == 0 && + skey_passcheck(pw->pw_name, response) != -1); xfree(response); } break; @@ -345,13 +291,15 @@ log("Unknown message during authentication: type %d", type); break; } + if (authenticated && pw == NULL) + fatal("internal error: authenticated for pw == NULL"); /* * Check if the user is logging in as root and root logins * are disallowed. * Note that root login is allowed for forced commands. */ - if (authenticated && pw->pw_uid == 0 && !options.permit_root_login) { + if (authenticated && pw && pw->pw_uid == 0 && !options.permit_root_login) { if (forced_command) { log("Root login accepted for forced command."); } else { @@ -367,10 +315,11 @@ type == SSH_CMSG_AUTH_PASSWORD) authlog = log; - authlog("%s %s for %.200s from %.200s port %d%s", + authlog("%s %s for %s%.100s from %.200s port %d%s", authenticated ? "Accepted" : "Failed", get_authname(type), - pw->pw_uid == 0 ? "ROOT" : pw->pw_name, + pw ? "" : "illegal user ", + pw && pw->pw_uid == 0 ? "ROOT" : luser, get_remote_ipaddr(), get_remote_port(), user); @@ -379,7 +328,7 @@ return; if (attempt > AUTH_FAIL_MAX) - packet_disconnect(AUTH_FAIL_MSG, pw->pw_name); + packet_disconnect(AUTH_FAIL_MSG, luser); /* Send a message indicating that the authentication attempt failed. */ packet_start(SSH_SMSG_FAILURE); @@ -419,28 +368,29 @@ /* Verify that the user is a valid user. */ pw = getpwnam(user); - if (!pw || !allowed_user(pw)) - do_fake_authloop1(user); - xfree(user); + if (pw && allowed_user(pw)) { + /* Take a copy of the returned structure. */ + memset(&pwcopy, 0, sizeof(pwcopy)); + pwcopy.pw_name = xstrdup(pw->pw_name); + pwcopy.pw_passwd = xstrdup(pw->pw_passwd); + pwcopy.pw_uid = pw->pw_uid; + pwcopy.pw_gid = pw->pw_gid; + pwcopy.pw_class = xstrdup(pw->pw_class); + pwcopy.pw_dir = xstrdup(pw->pw_dir); + pwcopy.pw_shell = xstrdup(pw->pw_shell); + pw = &pwcopy; + } else { + pw = NULL; + } - /* Take a copy of the returned structure. */ - memset(&pwcopy, 0, sizeof(pwcopy)); - pwcopy.pw_name = xstrdup(pw->pw_name); - pwcopy.pw_passwd = xstrdup(pw->pw_passwd); - pwcopy.pw_uid = pw->pw_uid; - pwcopy.pw_gid = pw->pw_gid; - pwcopy.pw_dir = xstrdup(pw->pw_dir); - pwcopy.pw_shell = xstrdup(pw->pw_shell); - pw = &pwcopy; - /* * If we are not running as root, the user must have the same uid as * the server. */ - if (getuid() != 0 && pw->pw_uid != getuid()) + if (getuid() != 0 && pw && pw->pw_uid != getuid()) packet_disconnect("Cannot change user when server not running as root."); - debug("Attempting authentication for %.100s.", pw->pw_name); + debug("Attempting authentication for %s%.100s.", pw ? "" : "illegal user ", user); /* If the user has no password, accept authentication immediately. */ if (options.password_authentication && @@ -450,13 +400,15 @@ auth_password(pw, "")) { /* Authentication with empty password succeeded. */ log("Login for user %s from %.100s, accepted without authentication.", - pw->pw_name, get_remote_ipaddr()); + user, get_remote_ipaddr()); } else { /* Loop until the user has been authenticated or the connection is closed, do_authloop() returns only if authentication is successfull */ - do_authloop(pw); + do_authloop(pw, user); } + if (pw == NULL) + fatal("internal error, authentication successfull for user '%.100s'", user); /* The user has been authenticated and accepted. */ packet_start(SSH_SMSG_SUCCESS);