diff options
Diffstat (limited to 'crypto/openssh/auth1.c')
| -rw-r--r-- | crypto/openssh/auth1.c | 445 |
1 files changed, 0 insertions, 445 deletions
diff --git a/crypto/openssh/auth1.c b/crypto/openssh/auth1.c deleted file mode 100644 index 18203fea8fbb..000000000000 --- a/crypto/openssh/auth1.c +++ /dev/null @@ -1,445 +0,0 @@ -/* - * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, 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 1.47 2003/02/06 21:22:42 markus Exp $"); -RCSID("$FreeBSD$"); - -#include "xmalloc.h" -#include "rsa.h" -#include "ssh1.h" -#include "packet.h" -#include "buffer.h" -#include "mpaux.h" -#include "log.h" -#include "servconf.h" -#include "compat.h" -#include "auth.h" -#include "channels.h" -#include "session.h" -#include "uidswap.h" -#include "monitor_wrap.h" - -/* import */ -extern ServerOptions options; - -/* - * convert ssh auth msg type into description - */ -static char * -get_authname(int type) -{ - static char buf[1024]; - switch (type) { - case SSH_CMSG_AUTH_PASSWORD: - return "password"; - case SSH_CMSG_AUTH_RSA: - return "rsa"; - case SSH_CMSG_AUTH_RHOSTS_RSA: - return "rhosts-rsa"; - case SSH_CMSG_AUTH_RHOSTS: - return "rhosts"; - case SSH_CMSG_AUTH_TIS: - case SSH_CMSG_AUTH_TIS_RESPONSE: - return "challenge-response"; -#if defined(KRB4) || defined(KRB5) - case SSH_CMSG_AUTH_KERBEROS: - return "kerberos"; -#endif - } - snprintf(buf, sizeof buf, "bad-auth-msg-%d", type); - return buf; -} - -/* - * read packets, try to authenticate the user and - * return only if authentication is successful - */ -static void -do_authloop(Authctxt *authctxt) -{ - int authenticated = 0; - u_int bits; - Key *client_host_key; - BIGNUM *n; - char *client_user, *password; - char info[1024]; - u_int dlen; - u_int ulen; - int prev, type = 0; - struct passwd *pw = authctxt->pw; - - debug("Attempting authentication for %s%.100s.", - authctxt->valid ? "" : "illegal user ", authctxt->user); - - /* If the user has no password, accept authentication immediately. */ - if (options.password_authentication && -#if defined(KRB4) || defined(KRB5) - (!options.kerberos_authentication || options.kerberos_or_local_passwd) && -#endif - PRIVSEP(auth_password(authctxt, ""))) { - auth_log(authctxt, 1, "without authentication", ""); - return; - } - - /* Indicate that authentication is needed. */ - packet_start(SSH_SMSG_FAILURE); - packet_send(); - packet_write_wait(); - - client_user = NULL; - - for (;;) { - /* default to fail */ - authenticated = 0; - - info[0] = '\0'; - - /* Get a packet from the client. */ - prev = type; - type = packet_read(); - - /* - * If we started challenge-response authentication but the - * next packet is not a response to our challenge, release - * the resources allocated by get_challenge() (which would - * normally have been released by verify_response() had we - * received such a response) - */ - if (prev == SSH_CMSG_AUTH_TIS && - type != SSH_CMSG_AUTH_TIS_RESPONSE) - abandon_challenge_response(authctxt); - - /* Process the packet. */ - switch (type) { - -#if defined(KRB4) || defined(KRB5) - case SSH_CMSG_AUTH_KERBEROS: - if (!options.kerberos_authentication) { - verbose("Kerberos authentication disabled."); - } else { - char *kdata = packet_get_string(&dlen); - packet_check_eom(); - - if (kdata[0] == 4) { /* KRB_PROT_VERSION */ -#ifdef KRB4 - KTEXT_ST tkt, reply; - tkt.length = dlen; - if (tkt.length < MAX_KTXT_LEN) - memcpy(tkt.dat, kdata, tkt.length); - - if (PRIVSEP(auth_krb4(authctxt, &tkt, - &client_user, &reply))) { - authenticated = 1; - snprintf(info, sizeof(info), - " tktuser %.100s", - client_user); - - packet_start( - SSH_SMSG_AUTH_KERBEROS_RESPONSE); - packet_put_string((char *) - reply.dat, reply.length); - packet_send(); - packet_write_wait(); - } -#endif /* KRB4 */ - } else { -#ifdef KRB5 - krb5_data tkt, reply; - tkt.length = dlen; - tkt.data = kdata; - - if (PRIVSEP(auth_krb5(authctxt, &tkt, - &client_user, &reply))) { - authenticated = 1; - snprintf(info, sizeof(info), - " tktuser %.100s", - client_user); - - /* Send response to client */ - packet_start( - SSH_SMSG_AUTH_KERBEROS_RESPONSE); - packet_put_string((char *) - reply.data, reply.length); - packet_send(); - packet_write_wait(); - - if (reply.length) - xfree(reply.data); - } -#endif /* KRB5 */ - } - xfree(kdata); - } - break; -#endif /* KRB4 || KRB5 */ - -#if defined(AFS) || defined(KRB5) - /* XXX - punt on backward compatibility here. */ - case SSH_CMSG_HAVE_KERBEROS_TGT: - packet_send_debug("Kerberos TGT passing disabled before authentication."); - break; -#ifdef AFS - case SSH_CMSG_HAVE_AFS_TOKEN: - packet_send_debug("AFS token passing disabled before authentication."); - break; -#endif /* AFS */ -#endif /* AFS || KRB5 */ - - case SSH_CMSG_AUTH_RHOSTS: - if (!options.rhosts_authentication) { - verbose("Rhosts authentication disabled."); - break; - } - /* - * Get client user name. Note that we just have to - * trust the client; this is one reason why rhosts - * authentication is insecure. (Another is - * IP-spoofing on a local network.) - */ - client_user = packet_get_string(&ulen); - packet_check_eom(); - - /* Try to authenticate using /etc/hosts.equiv and .rhosts. */ - authenticated = auth_rhosts(pw, client_user); - - snprintf(info, sizeof info, " ruser %.100s", client_user); - break; - - case SSH_CMSG_AUTH_RHOSTS_RSA: - if (!options.rhosts_rsa_authentication) { - verbose("Rhosts with RSA authentication disabled."); - break; - } - /* - * Get client user name. Note that we just have to - * trust the client; root on the client machine can - * claim to be any user. - */ - client_user = packet_get_string(&ulen); - - /* Get the client host key. */ - client_host_key = key_new(KEY_RSA1); - bits = packet_get_int(); - packet_get_bignum(client_host_key->rsa->e); - packet_get_bignum(client_host_key->rsa->n); - - if (bits != BN_num_bits(client_host_key->rsa->n)) - verbose("Warning: keysize mismatch for client_host_key: " - "actual %d, announced %d", - BN_num_bits(client_host_key->rsa->n), bits); - packet_check_eom(); - - authenticated = auth_rhosts_rsa(pw, client_user, - client_host_key); - key_free(client_host_key); - - snprintf(info, sizeof info, " ruser %.100s", client_user); - break; - - case SSH_CMSG_AUTH_RSA: - if (!options.rsa_authentication) { - verbose("RSA authentication disabled."); - break; - } - /* RSA authentication requested. */ - if ((n = BN_new()) == NULL) - fatal("do_authloop: BN_new failed"); - packet_get_bignum(n); - packet_check_eom(); - authenticated = auth_rsa(pw, n); - BN_clear_free(n); - break; - - case SSH_CMSG_AUTH_PASSWORD: - if (!options.password_authentication) { - verbose("Password authentication disabled."); - break; - } - /* - * Read user password. It is in plain text, but was - * transmitted over the encrypted channel so it is - * not visible to an outside observer. - */ - password = packet_get_string(&dlen); - packet_check_eom(); - - /* Try authentication with the password. */ - authenticated = PRIVSEP(auth_password(authctxt, password)); - - memset(password, 0, strlen(password)); - xfree(password); - break; - - case SSH_CMSG_AUTH_TIS: - debug("rcvd SSH_CMSG_AUTH_TIS"); - if (options.challenge_response_authentication == 1) { - char *challenge = get_challenge(authctxt); - if (challenge != NULL) { - debug("sending challenge '%s'", challenge); - packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE); - packet_put_cstring(challenge); - xfree(challenge); - packet_send(); - packet_write_wait(); - continue; - } - } - break; - case SSH_CMSG_AUTH_TIS_RESPONSE: - debug("rcvd SSH_CMSG_AUTH_TIS_RESPONSE"); - if (options.challenge_response_authentication == 1) { - char *response = packet_get_string(&dlen); - packet_check_eom(); - authenticated = verify_response(authctxt, response); - memset(response, 'r', dlen); - xfree(response); - } - break; - - default: - /* - * Any unknown messages will be ignored (and failure - * returned) during authentication. - */ - log("Unknown message during authentication: type %d", type); - break; - } -#ifdef BSD_AUTH - if (authctxt->as) { - auth_close(authctxt->as); - authctxt->as = NULL; - } -#endif - if (!authctxt->valid && authenticated) - fatal("INTERNAL ERROR: authenticated invalid user %s", - authctxt->user); - -#ifdef _UNICOS - if (type == SSH_CMSG_AUTH_PASSWORD && !authenticated) - cray_login_failure(authctxt->user, IA_UDBERR); - if (authenticated && cray_access_denied(authctxt->user)) { - authenticated = 0; - fatal("Access denied for user %s.",authctxt->user); - } -#endif /* _UNICOS */ - -#ifdef HAVE_CYGWIN - if (authenticated && - !check_nt_auth(type == SSH_CMSG_AUTH_PASSWORD, pw)) { - packet_disconnect("Authentication rejected for uid %d.", - pw == NULL ? -1 : pw->pw_uid); - authenticated = 0; - } -#else - /* Special handling for root */ - if (authenticated && authctxt->pw->pw_uid == 0 && - !auth_root_allowed(get_authname(type))) - authenticated = 0; -#endif -#ifdef USE_PAM - if (!use_privsep && authenticated && - !do_pam_account(pw->pw_name, client_user)) - authenticated = 0; -#endif - - /* Log before sending the reply */ - auth_log(authctxt, authenticated, get_authname(type), info); - - if (client_user != NULL) { - xfree(client_user); - client_user = NULL; - } - - if (authenticated) - return; - - if (authctxt->failures++ > AUTH_FAIL_MAX) { - packet_disconnect(AUTH_FAIL_MSG, authctxt->user); - } - - packet_start(SSH_SMSG_FAILURE); - packet_send(); - packet_write_wait(); - } -} - -/* - * Performs authentication of an incoming connection. Session key has already - * been exchanged and encryption is enabled. - */ -Authctxt * -do_authentication(void) -{ - Authctxt *authctxt; - u_int ulen; - char *user, *style = NULL; - - /* Get the name of the user that we wish to log in as. */ - packet_read_expect(SSH_CMSG_USER); - - /* Get the user name. */ - user = packet_get_string(&ulen); - packet_check_eom(); - - if ((style = strchr(user, ':')) != NULL) - *style++ = '\0'; - -#ifdef KRB5 - /* XXX - SSH.com Kerberos v5 braindeath. */ - if ((datafellows & SSH_BUG_K5USER) && - options.kerberos_authentication) { - char *p; - if ((p = strchr(user, '@')) != NULL) - *p = '\0'; - } -#endif - - authctxt = authctxt_new(); - authctxt->user = user; - authctxt->style = style; - - /* Verify that the user is a valid user. */ - if ((authctxt->pw = PRIVSEP(getpwnamallow(user))) != NULL) - authctxt->valid = 1; - else - debug("do_authentication: illegal user %s", user); - - setproctitle("%s%s", authctxt->pw ? user : "unknown", - use_privsep ? " [net]" : ""); - -#ifdef USE_PAM - PRIVSEP(start_pam(authctxt->pw == NULL ? "NOUSER" : user)); -#endif - - /* - * If we are not running as root, the user must have the same uid as - * the server. (Unless you are running Windows) - */ -#ifndef HAVE_CYGWIN - if (!use_privsep && getuid() != 0 && authctxt->pw && - authctxt->pw->pw_uid != getuid()) - packet_disconnect("Cannot change user when server not running as root."); -#endif - - /* - * Loop until the user has been authenticated or the connection is - * closed, do_authloop() returns only if authentication is successful - */ - do_authloop(authctxt); - - /* The user has been authenticated and accepted. */ - packet_start(SSH_SMSG_SUCCESS); - packet_send(); - packet_write_wait(); - - return (authctxt); -} |