From db65e8fdedadaf79df2d8393a4d43e9094c80649 Mon Sep 17 00:00:00 2001 From: Ben Lindstrom Date: Fri, 19 Jan 2001 04:26:52 +0000 Subject: Please grep through the source and look for 'ISSUE' comments and verify that I was able to get all the portable bits in the right location. As for the SKEY comment there is an email out to Markus as to how it should be resolved. Until then I just #ifdef SKEY/#endif out the whole block. - (bal) OpenBSD Resync - markus@cvs.openbsd.org 2001/01/18 16:20:21 [log-client.c log-server.c log.c readconf.c servconf.c ssh.1 ssh.h sshd.8 sshd.c] log() is at pri=LOG_INFO, since LOG_NOTICE goes to /dev/console on many systems - markus@cvs.openbsd.org 2001/01/18 16:59:59 [auth-passwd.c auth.c auth.h auth1.c auth2.c serverloop.c session.c session.h sshconnect1.c] 1) removes fake skey from sshd, since this will be much harder with /usr/libexec/auth/login_XXX 2) share/unify code used in ssh-1 and ssh-2 authentication (server side) 3) make addition of BSD_AUTH and other challenge reponse methods easier. - markus@cvs.openbsd.org 2001/01/18 17:12:43 [auth-chall.c auth2-chall.c] rename *-skey.c *-chall.c since the files are not skey specific --- auth1.c | 216 ++++++++++++++++++++++++++-------------------------------------- 1 file changed, 88 insertions(+), 128 deletions(-) (limited to 'auth1.c') diff --git a/auth1.c b/auth1.c index 51ed8f773..0f21c4c7c 100644 --- a/auth1.c +++ b/auth1.c @@ -10,7 +10,7 @@ */ #include "includes.h" -RCSID("$OpenBSD: auth1.c,v 1.10 2001/01/07 19:06:25 markus Exp $"); +RCSID("$OpenBSD: auth1.c,v 1.11 2001/01/18 16:59:59 markus Exp $"); #ifdef HAVE_OSF_SIA # include @@ -56,13 +56,12 @@ get_authname(int type) return "rhosts-rsa"; case SSH_CMSG_AUTH_RHOSTS: return "rhosts"; + case SSH_CMSG_AUTH_TIS: + case SSH_CMSG_AUTH_TIS_RESPONSE: + return "challenge-response"; #ifdef KRB4 case SSH_CMSG_AUTH_KERBEROS: return "kerberos"; -#endif -#ifdef SKEY - case SSH_CMSG_AUTH_TIS_RESPONSE: - return "s/key"; #endif } snprintf(buf, sizeof buf, "bad-auth-msg-%d", type); @@ -70,27 +69,40 @@ get_authname(int type) } /* - * read packets and try to authenticate local user 'luser'. - * return if authentication is successful. 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. + * read packets, try to authenticate the user and + * return only if authentication is successful */ void -do_authloop(struct passwd * pw, char *luser) +do_authloop(Authctxt *authctxt) { int authenticated = 0; - int attempt = 0; u_int bits; RSA *client_host_key; BIGNUM *n; char *client_user, *password; - char user[1024]; + char info[1024]; u_int dlen; int plen, nlen, elen; u_int ulen; int type = 0; - void (*authlog) (const char *fmt,...) = verbose; + 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 && +#ifdef KRB4 + (!options.kerberos_authentication || options.kerberos_or_local_passwd) && +#endif +#ifdef USE_PAM /* ISSUE: Right?? */ + auth_pam_password(pw, password)) { +#else + auth_password(pw, "")) { +#endif + auth_log(authctxt, 1, "without authentication", ""); + return; + } /* Indicate that authentication is needed. */ packet_start(SSH_SMSG_FAILURE); @@ -99,11 +111,11 @@ do_authloop(struct passwd * pw, char *luser) client_user = NULL; - for (attempt = 1;; attempt++) { + for (;;) { /* default to fail */ authenticated = 0; - strlcpy(user, "", sizeof user); + info[0] = '\0'; /* Get a packet from the client. */ type = packet_read(&plen); @@ -120,7 +132,7 @@ do_authloop(struct passwd * pw, char *luser) char *tgt = packet_get_string(&dlen); packet_integrity_check(plen, 4 + dlen, type); if (!auth_kerberos_tgt(pw, tgt)) - verbose("Kerberos tgt REFUSED for %.100s", luser); + verbose("Kerberos tgt REFUSED for %.100s", authctxt->user); xfree(tgt); } continue; @@ -134,7 +146,7 @@ do_authloop(struct passwd * pw, char *luser) 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 %.100s", luser); + verbose("AFS token REFUSED for %.100s", authctxt->user); xfree(token_string); } continue; @@ -142,7 +154,6 @@ do_authloop(struct passwd * pw, char *luser) #ifdef KRB4 case SSH_CMSG_AUTH_KERBEROS: if (!options.kerberos_authentication) { - /* packet_get_all(); */ verbose("Kerberos authentication disabled."); break; } else { @@ -152,17 +163,17 @@ do_authloop(struct passwd * pw, char *luser) char *kdata = packet_get_string((u_int *) &auth.length); packet_integrity_check(plen, 4 + auth.length, type); - if (auth.length < MAX_KTXT_LEN) - memcpy(auth.dat, kdata, auth.length); - xfree(kdata); - - if (pw != NULL) { + if (authctxt->valid) { + if (auth.length < MAX_KTXT_LEN) + memcpy(auth.dat, kdata, auth.length); authenticated = auth_krb4(pw->pw_name, &auth, &tkt_user); if (authenticated) { - snprintf(user, sizeof user, " tktuser %s", tkt_user); + snprintf(info, sizeof info, + " tktuser %.100s", tkt_user); xfree(tkt_user); } } + xfree(kdata); } break; #endif /* KRB4 */ @@ -184,7 +195,7 @@ do_authloop(struct passwd * pw, char *luser) /* Try to authenticate using /etc/hosts.equiv and .rhosts. */ authenticated = auth_rhosts(pw, client_user); - snprintf(user, sizeof user, " ruser %s", client_user); + snprintf(info, sizeof info, " ruser %.100s", client_user); break; case SSH_CMSG_AUTH_RHOSTS_RSA: @@ -219,7 +230,7 @@ do_authloop(struct passwd * pw, char *luser) authenticated = auth_rhosts_rsa(pw, client_user, client_host_key); RSA_free(client_host_key); - snprintf(user, sizeof user, " ruser %s", client_user); + snprintf(info, sizeof info, " ruser %.100s", client_user); break; case SSH_CMSG_AUTH_RSA: @@ -267,22 +278,19 @@ do_authloop(struct passwd * pw, char *luser) xfree(password); break; -#ifdef SKEY +#ifdef SKEY /* ISSUE: Is this right? we don't define + having skey_authentication in + servconf.h by default so I assume + we need to deal with this via #ifdef + in some reasonable way */ case SSH_CMSG_AUTH_TIS: debug("rcvd SSH_CMSG_AUTH_TIS"); if (options.skey_authentication == 1) { - char *skeyinfo = NULL; - if (pw != NULL) - skeyinfo = skey_keyinfo(pw->pw_name); - if (skeyinfo == NULL) { - 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); + char *challenge = get_challenge(authctxt, authctxt->style); + if (challenge != NULL) { + debug("sending challenge '%s'", challenge); packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE); - packet_put_cstring(skeyinfo); + packet_put_cstring(challenge); packet_send(); packet_write_wait(); continue; @@ -293,20 +301,14 @@ do_authloop(struct passwd * pw, char *luser) debug("rcvd SSH_CMSG_AUTH_TIS_RESPONSE"); if (options.skey_authentication == 1) { char *response = packet_get_string(&dlen); - debug("skey response == '%s'", response); + debug("got response '%s'", response); packet_integrity_check(plen, 4 + dlen, type); - authenticated = (pw != NULL && - skey_haskey(pw->pw_name) == 0 && - skey_passcheck(pw->pw_name, response) != -1); + authenticated = verify_response(authctxt, response); + memset(response, 'r', dlen); xfree(response); } break; -#else - case SSH_CMSG_AUTH_TIS: - /* TIS Authentication is unsupported */ - log("TIS authentication unsupported."); - break; -#endif +#endif /* ISSUE: End of wrong SKEY defines */ default: /* @@ -316,10 +318,11 @@ do_authloop(struct passwd * pw, char *luser) log("Unknown message during authentication: type %d", type); break; } - if (authenticated && pw == NULL) - fatal("internal error: authenticated for pw == NULL"); + if (!authctxt->valid && authenticated) + fatal("INTERNAL ERROR: authenticated invalid user %s", + authctxt->user); -#ifdef HAVE_CYGWIN +#ifdef HAVE_CYGWIN /* ISSUE: Right place? */ if (authenticated && !check_nt_auth(type == SSH_CMSG_AUTH_PASSWORD,pw->pw_uid)) { packet_disconnect("Authentication rejected for uid %d.", @@ -328,41 +331,18 @@ do_authloop(struct passwd * pw, char *luser) } #endif - /* - * 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->pw_uid == 0 && !options.permit_root_login) { - if (forced_command) { - log("Root login accepted for forced command."); - } else { - authenticated = 0; - log("ROOT LOGIN REFUSED FROM %.200s", - get_canonical_hostname()); - } - } - - /* Raise logging level */ - if (authenticated || - attempt == AUTH_FAIL_LOG || - type == SSH_CMSG_AUTH_PASSWORD) - authlog = log; - - authlog("%s %s for %s%.100s from %.200s port %d%s", - authenticated ? "Accepted" : "Failed", - get_authname(type), - pw ? "" : "illegal user ", - pw && pw->pw_uid == 0 ? "ROOT" : luser, - get_remote_ipaddr(), - get_remote_port(), - user); + /* Special handling for root */ + if (authenticated && authctxt->pw->pw_uid == 0 && !auth_root_allowed()) + authenticated = 0; -#ifdef USE_PAM +#ifdef USE_PAM /* ISSUE: Right place? */ if (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; @@ -371,14 +351,13 @@ do_authloop(struct passwd * pw, char *luser) if (authenticated) return; - if (attempt > AUTH_FAIL_MAX) { + if (authctxt->failures++ > AUTH_FAIL_MAX) { #ifdef WITH_AIXAUTHENTICATE loginfailed(user,get_canonical_hostname(),"ssh"); #endif /* WITH_AIXAUTHENTICATE */ - packet_disconnect(AUTH_FAIL_MSG, luser); + packet_disconnect(AUTH_FAIL_MSG, authctxt->user); } - /* Send a message indicating that the authentication attempt failed. */ packet_start(SSH_SMSG_FAILURE); packet_send(); packet_write_wait(); @@ -392,10 +371,11 @@ do_authloop(struct passwd * pw, char *luser) void do_authentication() { - struct passwd *pw, pwcopy; + Authctxt *authctxt; + struct passwd *pw; int plen; u_int ulen; - char *user; + char *user, *style = NULL; /* Get the name of the user that we wish to log in as. */ packet_read_expect(&plen, SSH_CMSG_USER); @@ -404,6 +384,13 @@ do_authentication() user = packet_get_string(&ulen); packet_integrity_check(plen, (4 + ulen), SSH_CMSG_USER); + if ((style = strchr(user, ':')) != NULL) + *style++ = 0; + + authctxt = authctxt_new(); + authctxt->user = user; + authctxt->style = style; + setproctitle("%s", user); #ifdef AFS @@ -417,21 +404,13 @@ do_authentication() /* Verify that the user is a valid user. */ pw = getpwnam(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; -#ifdef HAVE_PW_CLASS_IN_PASSWD - pwcopy.pw_class = xstrdup(pw->pw_class); -#endif - pwcopy.pw_dir = xstrdup(pw->pw_dir); - pwcopy.pw_shell = xstrdup(pw->pw_shell); - pw = &pwcopy; + authctxt->valid = 1; + pw = pwcopy(pw); } else { + debug("do_authentication: illegal user %s", user); pw = NULL; } + authctxt->pw = pw; #ifdef USE_PAM if (pw) @@ -447,44 +426,25 @@ do_authentication() packet_disconnect("Cannot change user when server not running as root."); #endif - debug("Attempting authentication for %s%.100s.", pw ? "" : "illegal user ", user); - - /* If the user has no password, accept authentication immediately. */ - if (options.password_authentication && -#ifdef KRB4 - (!options.kerberos_authentication || options.kerberos_or_local_passwd) && -#endif /* KRB4 */ -#ifdef USE_PAM - auth_pam_password(pw, "")) { -#elif defined(HAVE_OSF_SIA) - (sia_validate_user(NULL, saved_argc, saved_argv, - get_canonical_hostname(), pw->pw_name, NULL, 0, - NULL, "") == SIASUCCESS)) { -#else /* !HAVE_OSF_SIA && !USE_PAM */ - auth_password(pw, "")) { -#endif /* USE_PAM */ - /* Authentication with empty password succeeded. */ - log("Login for user %s from %.100s, accepted without authentication.", - user, get_remote_ipaddr()); - } else { - /* Loop until the user has been authenticated or the - connection is closed, do_authloop() returns only if - authentication is successful */ - do_authloop(pw, user); - } - if (pw == NULL) - fatal("internal error, authentication successful for user '%.100s'", user); + /* + * 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(); + #ifdef WITH_AIXAUTHENTICATE /* We don't have a pty yet, so just label the line as "ssh" */ - if (loginsuccess(user,get_canonical_hostname(),"ssh",&aixloginmsg) < 0) + if (loginsuccess(authctxt->user,get_canonical_hostname(),"ssh",&aixloginmsg) < 0) aixloginmsg = NULL; #endif /* WITH_AIXAUTHENTICATE */ - xfree(user); + + xfree(authctxt->user); + xfree(authctxt); /* Perform session preparation. */ do_authenticated(pw); -- cgit v1.2.3