X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=user_list.c;h=fe1b946b1e96596ce6cd8c7949407bf7a341cfb6;hp=3c0b4f856546a2173c77696f80e0c554a646985c;hb=a22e734cd89015a71d0dd7cf895799c440805847;hpb=271c83d4fd9411be628fa650ce595ac79754d22e

diff --git a/user_list.c b/user_list.c
index 3c0b4f85..fe1b946b 100644
--- a/user_list.c
+++ b/user_list.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2011 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -18,6 +18,7 @@
 #include "string.h"
 #include "list.h"
 #include "user_list.h"
+#include "rc4.h"
 
 static struct list_head user_list;
 
@@ -42,7 +43,7 @@ static void populate_user_list(char *user_list_file)
 		struct user *u;
 		RSA *rsa;
 
-		ret = para_fgets(line, MAXLINE, file_ptr);
+		ret = para_fgets(line, sizeof(line), file_ptr);
 		if (ret <= 0)
 			break;
 		if (sscanf(line,"%200s %200s %200s %200s", w, n, k, p) < 3)
@@ -56,8 +57,15 @@ static void populate_user_list(char *user_list_file)
 				para_strerror(-ret));
 			continue;
 		}
-		if (ret < CHALLENGE_SIZE + 2 * CHALLENGE_SIZE + 41) {
-			PARA_WARNING_LOG("rsa key for %s too small\n", n);
+		/*
+		 * In order to encrypt len := CHALLENGE_SIZE + 2 * RC4_KEY_LEN
+		 * bytes using RSA_public_encrypt() with EME-OAEP padding mode,
+		 * RSA_size(rsa) must be greater than len + 41. So ignore keys
+		 * which are too short. For details see RSA_public_encrypt(3).
+		 */
+		if (ret <= CHALLENGE_SIZE + 2 * RC4_KEY_LEN + 41) {
+			PARA_WARNING_LOG("rsa key %s too short (%d)\n",
+				k, ret);
 			rsa_free(rsa);
 			continue;
 		}