1 files changed, 81 insertions, 7 deletions

diff --git a/auth2.c b/auth2.c
index e2543a501..3849b07ab 100644
--- a/auth2.c
+++ b/auth2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth2.c,v 1.115 2007/04/14 22:01:58 stevesk Exp $ */
+/* $OpenBSD: auth2.c,v 1.119 2008/07/04 23:30:16 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -26,12 +26,17 @@
 #include "includes.h"
 
 #include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/uio.h>
 
+#include <fcntl.h>
 #include <pwd.h>
 #include <stdarg.h>
 #include <string.h>
+#include <unistd.h>
 
 #include "xmalloc.h"
+#include "atomicio.h"
 #include "ssh2.h"
 #include "packet.h"
 #include "log.h"
@@ -89,12 +94,75 @@ static void input_userauth_request(int, u_int32_t, void *);
 /* helper */
 static Authmethod *authmethod_lookup(const char *);
 static char *authmethods_get(void);
-int user_key_allowed(struct passwd *, Key *);
+
+char *
+auth2_read_banner(void)
+{
+        struct stat st;
+        char *banner = NULL;
+        size_t len, n;
+        int fd;
+
+        if ((fd = open(options.banner, O_RDONLY)) == -1)
+                return (NULL);
+        if (fstat(fd, &st) == -1) {
+                close(fd);
+                return (NULL);
+        }
+        if (st.st_size > 1*1024*1024) {
+                close(fd);
+                return (NULL);
+        }
+
+        len = (size_t)st.st_size;               /* truncate */
+        banner = xmalloc(len + 1);
+        n = atomicio(read, fd, banner, len);
+        close(fd);
+
+        if (n != len) {
+                xfree(banner);
+                return (NULL);
+        }
+        banner[n] = '\0';
+
+        return (banner);
+}
+
+void
+userauth_send_banner(const char *msg)
+{
+        if (datafellows & SSH_BUG_BANNER)
+                return;
+
+        packet_start(SSH2_MSG_USERAUTH_BANNER);
+        packet_put_cstring(msg);
+        packet_put_cstring("");         /* language, unused */
+        packet_send();
+        debug("%s: sent", __func__);
+}
+
+static void
+userauth_banner(void)
+{
+        char *banner = NULL;
+
+        if (options.banner == NULL ||
+            strcasecmp(options.banner, "none") == 0 ||
+            (datafellows & SSH_BUG_BANNER) != 0)
+                return;
+
+        if ((banner = PRIVSEP(auth2_read_banner())) == NULL)
+                goto done;
+        userauth_send_banner(banner);
+
+done:
+        if (banner)
+                xfree(banner);
+}
 
 /*
  * loop until authctxt->success == TRUE
  */
-
 void
 do_authentication2(Authctxt *authctxt)
 {
@@ -188,6 +256,7 @@ input_userauth_request(int type, u_int32_t seq, void *ctxt)
                 authctxt->role = role ? xstrdup(role) : NULL;
                 if (use_privsep)
                         mm_inform_authserv(service, style, role);
+                userauth_banner();
         } else if (strcmp(user, authctxt->user) != 0 ||
             strcmp(service, authctxt->service) != 0) {
                 packet_disconnect("Change of username or service not allowed: "
@@ -207,7 +276,7 @@ input_userauth_request(int type, u_int32_t seq, void *ctxt)
 
         /* try to authenticate user */
         m = authmethod_lookup(method);
-        if (m != NULL) {
+        if (m != NULL && authctxt->failures < options.max_authtries) {
                 debug2("input_userauth_request: try method %s", method);
                 authenticated = m->userauth(authctxt);
         }
@@ -274,9 +343,13 @@ userauth_finish(Authctxt *authctxt, int authenticated, char *method)
                 /* now we can break out */
                 authctxt->success = 1;
         } else {
-                /* Dont count server configuration issues against the client */
-                if (!authctxt->server_caused_failure && 
-                    authctxt->failures++ > options.max_authtries) {
+
+                /* Allow initial try of "none" auth without failure penalty */
+                /* Don't count server configuration issues against the client */
+                if (!authctxt->server_caused_failure &&
+                    (authctxt->attempt > 1 || strcmp(method, "none") != 0))
+                        authctxt->failures++;
+                if (authctxt->failures >= options.max_authtries) {
 #ifdef SSH_AUDIT_EVENTS
                         PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES));
 #endif
@@ -332,3 +405,4 @@ authmethod_lookup(const char *name)
             name ? name : "NULL");
         return NULL;
 }
+