1 files changed, 88 insertions, 128 deletions

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 <sia.h>
@@ -56,41 +56,53 @@ 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);
         return buf;
 }
 
 /*
- * 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);