Added EAP support with MD5-Challenge and SRP-SHA1 methods. Tested

on Linux (with both methods) and on Solaris (just MD5-Challenge).
Fixed several Makefiles that were missing references to required
modules such as tty.o.

Author: carlsonj

README.eap-srp

@@ -0,0 +1,149 @@
+EAP with MD5-Challenge and SRP-SHA1 support
+by James Carlson, Sun Microsystems
+Version 2, September 22nd, 2002
+
+
+1.  What it does
+
+    The Extensible Authentication Protocol (EAP; RFC 2284) is a
+    security protocol that can be used with PPP.  It provides a means
+    to plug in multiple optional authentication methods.
+
+    This implementation includes the required default MD5-Challenge
+    method, which is similar to CHAP (RFC 1994), as well as the new
+    SRP-SHA1 method.  This latter method relies on an exchange that is
+    not vulnerable to dictionary attacks (as is CHAP), does not
+    require the server to keep a cleartext copy of the secret (as in
+    CHAP), supports identity privacy, and produces a temporary shared
+    key that could be used for data encryption.
+
+    The SRP-SHA1 method is based on draft-ietf-pppext-eap-srp-03.txt,
+    a work in progress.
+
+2.  Required libraries
+
+    Two other packages are required first.  Download and install
+    OpenSSL and Thomas Wu's SRP implementation.
+
+	http://www.openssl.org/ (or ftp://ftp.openssl.org/source/)
+	http://srp.stanford.edu/
+
+    Follow the directions in each package to install the SSL and SRP
+    libraries.  Once SRP is installed, you may run tconf as root to
+    create known fields, if desired.  (This step is not required.)
+
+3.  Installing the patch
+
+    The EAP-SRP patch described here is integrated into this version
+    of pppd.  The following patch may be used with older pppd sources:
+
+	ftp://playground.sun.com/carlsonj/eap/ppp-2.4.1-eap-1.tar.gz
+
+    Configure, compile, and install as root.  You may want to edit
+    pppd/Makefile after configuring to enable or disable optional
+    features.
+
+	% ./configure
+	% make
+	% su
+	# make install
+
+    If you use csh or tcsh, run "rehash" to pick up the new commands.
+
+    If you're using Solaris, and you run into trouble with the
+    pseudonym feature on the server side ("no DES here" shows in the
+    log file), make sure that you have the "domestic" versions of the
+    DES libraries linked.  You should see "crypt_d" in "ldd
+    /usr/local/bin/pppd".  If you see "crypt_i" instead, then make
+    sure that /usr/lib/libcrypt.* links to /usr/lib/libcrypt_d.*.  (If
+    you have the international version of Solaris, then you won't have
+    crypt_d.  You might want to find an alternative DES library.)
+
+4.  Adding the secrets
+
+    On the EAP SRP-SHA1 client side, access to the cleartext secret is
+    required.  This can be done in two ways:
+
+	- Enter the client name, server name, and password in the
+          /etc/ppp/srp-secrets file.  This file has the same format as
+          the existing chap-secrets and pap-secrets files.
+
+	  clientname servername "secret here"
+
+	- Use the "password" option in any of the standard
+          configuration files (or the command line) to specify the
+          secret.
+
+	  password "secret here"
+
+    On the EAP SRP-SHA1 server side, a secret verifier is required.
+    This is a one-way hash of the client's name and password.  To
+    generate this value, run the srp-entry program (see srp-entry(8)).
+    This program prompts for the client name and the passphrase (the
+    secret).  The output will be an entry, such as the following,
+    suitable for use in the server's srp-secrets file.  Note that if
+    this is transferred by cut-and-paste, the entry must be a single
+    line of text in the file.
+
+pppuser srpserver 0:LFDpwg4HBLi4/kWByzbZpW6pE95/iIWBSt7L.DAkHsvwQphtiq0f6reoUy/1LC1qYqjcrV97lCDmQHQd4KIACGgtkhttLdP3KMowvS0wLXLo25FPJeG2sMAUEWu/HlJPn2/gHyh9aT.ZxUs5MsoQ1E61sJkVBc.2qze1CdZiQGTK3qtWRP6DOpM1bfhKtPoVm.g.MiCcTMWzc54xJUIA0mgKtpthE3JrqCc81cXUt4DYi5yBzeeGTqrI0z2/Gj8Jp7pS4Fkq3GmnYjMxnKfQorFXNwl3m7JSaPa8Gj9/BqnorJOsnSMlIhBe6dy4CYytuTbNb4Wv/nFkmSThK782V:2cIyMp1yKslQgE *
+
+    The "secret" field consists of three entries separated by colons.
+    The first entry is the index of the modulus and generator from
+    SRP's /etc/tpasswd.conf.  If the special value 0 is used, then the
+    well-known modulus/generator value is used (this is recommended,
+    because it is much faster).  The second value is the verifier
+    value.  The third is the password "salt."  These latter two values
+    are encoded in base64 notation.
+
+    For EAP MD5-Challenge, both client and server use the existing
+    /etc/ppp/chap-secrets file.
+
+5.  Configuration options
+
+    There are two main options relating to EAP available for the
+    client.  These are:
+
+	refuse-eap		- refuse to authenticate with EAP
+	srp-use-pseudonym	- use the identity privacy if
+				  offered by server
+
+    The second option stores a pseudonym, if offered by the EAP
+    SRP-SHA1 server, in the $HOME/.ppp_pseudonym file.  The pseudonym
+    is typically an encrypted version of the client identity.  During
+    EAP start-up, the pseudonym stored in this file is offered to the
+    peer as the identity.  If this is accepted by the peer, then
+    eavesdroppers will be unable to determine the identity of the
+    client.  Each time the client is authenticated, the server will
+    offer a new pseudoname to the client using an obscured (reversibly
+    encrypted) message.  Thus, access across successive sessions
+    cannot be tracked.
+
+    There are two main options for EAP on the server:
+
+	require-eap		- require client to use EAP
+	srp-pn-secret "string"	- set server's pseudoname secret
+
+    The second option sets the long-term secret used on the server to
+    encrypt the user's identity to produce pseudonames.  The
+    pseudoname is constructed by hashing this string with the current
+    date (to the nearest day) with SHA1, then using this hash as the
+    key for a DES encryption of the client's name.  The date is added
+    to the hash for two reasons.  First, this allows the pseudonym to
+    change daily.  Second, it allows the server to decode any previous
+    pseudonym by trying previous dates.
+
+    See the pppd(8) man page for additional options.
+
+6.  Comments welcome!
+
+    This is still an experimental implementation.  It has been tested
+    and reviewed carefully for correctness, but may still be
+    incomplete or have other flaws.  All comments are welcome.  Please
+    address them to the author:
+
+		[email protected]
+
+    or, for EAP itself or the SRP extensions to EAP, to the IETF PPP
+    Extensions working group:
+
+		[email protected]

configure

@@ -1,5 +1,5 @@
 #!/bin/sh
-# $Id: configure,v 1.29 2002/09/07 05:15:25 carlsonj Exp $
+# $Id: configure,v 1.30 2002/11/02 19:48:12 carlsonj Exp $
 
 #  if [ -d /NextApps ]; then
 #    system="NeXTStep"
@@ -21,8 +21,8 @@ case $system in
 #      [0-3]*)	state="ancient";;
 #      4*)	state="known"; ksrc="sunos4"; makext="sunos4";;
       5.[7-9]*|5.[1-9][0-9])	state="known"; ksrc="solaris"; makext="sol2";
-              case $arch in
-		sun4u)	archvariant='-64';;
+              case "`/usr/bin/isainfo -k`" in
+		sparcv9)	archvariant='-64';;
 		*)	;;
 	      esac;;
       5.[1-6]*)	state="known"; ksrc="solaris"; makext="sol2";;
@@ -33,7 +33,7 @@ case $system in
     elif gcc --version >/dev/null 2>&1; then
       archvariant=gcc$archvariant
       compiletype=.gcc
-      if [ "$arch" = "sun4u" ]; then
+      if [ "$archvariant" = "gcc-64" ]; then
         ( cd /tmp; touch ppp$$.c
 	  gcc -c -m64 ppp$$.c >/dev/null 2>&1 || (
 	    echo "gcc is unable to make 64 bit modules, and your $arch system needs them."
@@ -125,10 +125,12 @@ case $state in
     echo "This is a newer release of $system than is supported by"
     echo "this software.  It may or may not work.";;
   unknown)
-    echo "This software has not been ported to this system.  Sorry.";;
+    echo "This software has not been ported to $system.  Sorry.";;
   notincluded)
-    echo "Support for this system has not been included"
+    echo "Support for $system has not been included"
     echo "in this distribution.  Sorry.";;
+  known)
+    echo "Configuring for $system";;
 esac
 
 if [ -d "$ksrc" ]; then

include/net/ppp_defs.h

@@ -1,4 +1,4 @@
-/*	$Id: ppp_defs.h,v 1.15 2002/05/21 17:26:48 dfs Exp $	*/
+/*	$Id: ppp_defs.h,v 1.16 2002/11/02 19:48:12 carlsonj Exp $	*/
 
 /*
  * ppp_defs.h - PPP definitions.
@@ -85,6 +85,7 @@
 #define PPP_LQR		0xc025	/* Link Quality Report protocol */
 #define PPP_CHAP	0xc223	/* Cryptographic Handshake Auth. Protocol */
 #define PPP_CBCP	0xc029	/* Callback Control Protocol */
+#define PPP_EAP		0xc227	/* Extensible Authentication Protocol */
 
 /*
  * Values for FCS calculations.

pppd/Makefile.NeXT

@@ -1,17 +1,17 @@
 #
 # pppd makefile for NeXT
 #
-# $Orignial: Makefile.ultrix,v 1.4 1994/09/01 00:40:40 paulus Exp $
-# $Id: Makefile.NeXT,v 1.7 2002/05/21 17:26:48 dfs Exp $
+# $Original: Makefile.ultrix,v 1.4 1994/09/01 00:40:40 paulus Exp $
+# $Id: Makefile.NeXT,v 1.8 2002/11/02 19:48:12 carlsonj Exp $
 #
 
 ARCHFLAGS = 
 
 BINDIR = /usr/local/ppp/bin
 MANDIR = /usr/local/ppp/man
 
-OBJS = main.o magic.o fsm.o lcp.o ipcp.o upap.o chap.o md5.o ccp.o \
-	ecp.o auth.o options.o demand.o utils.o sys-NeXT.o
+OBJS = main.o magic.o fsm.o lcp.o ipcp.o upap.o chap.o eap.o md5.o ccp.o \
+	ecp.o auth.o options.o demand.o utils.o sys-NeXT.o tty.o
 
 #
 # For HPPA and SPARC, define FIXSIGS to get around posix bugs in

pppd/Makefile.aix4

@@ -1,6 +1,6 @@
 #
 # pppd makefile for AIX 4.1
-# $Id: Makefile.aix4,v 1.5 2002/05/21 17:26:48 dfs Exp $
+# $Id: Makefile.aix4,v 1.6 2002/11/02 19:48:12 carlsonj Exp $
 #
 #ifndef BINDIR
 BINDIR = /usr/sbin
@@ -10,12 +10,14 @@ MANDIR = /usr/man
 #ENDIF
 
 PPPDSRCS = main.c magic.c fsm.c lcp.c ipcp.c upap.c chap.c md5.c ccp.c \
-	ecp.c auth.c options.c demand.c utils.c sys-aix4.c \
-	gencode.c grammar.c scanner.c nametoaddr.c optimize.c
+	ecp.c auth.c options.c demand.c utils.c sys-aix4.c eap.c tty.c
 
 PPPDOBJS = main.o magic.o fsm.o lcp.o ipcp.o upap.o chap.o md5.o ccp.o \
-	ecp.o auth.o options.o demand.o utils.o sys-aix4.o \
-	gencode.o grammar.o scanner.o nametoaddr.o optimize.o
+	ecp.o auth.o options.o demand.o utils.o sys-aix4.o eap.o tty.o
+
+# xxx what are these?  They're not here.
+#	gencode.c grammar.c scanner.c nametoaddr.c optimize.c
+#	gencode.o grammar.o scanner.o nametoaddr.o optimize.o
 
 CC = xlc
 DEBUG_FLAGS = -DDEBUGALL

pppd/Makefile.bsd

@@ -1,4 +1,4 @@
-#	$Id: Makefile.bsd,v 1.16 2002/05/21 17:26:48 dfs Exp $
+#	$Id: Makefile.bsd,v 1.17 2002/11/02 19:48:12 carlsonj Exp $
 
 BINDIR?= /usr/sbin
 # -D_BITYPES is for FreeBSD, which doesn't define anything to
@@ -8,7 +8,7 @@ CFLAGS+= -g -I../include -DHAVE_PATHS_H -D_BITYPES
 
 PROG=	pppd
 SRCS=	main.c magic.c fsm.c lcp.c ipcp.c upap.c chap.c md5.c ccp.c \
-	ecp.c demand.c auth.c options.c utils.c sys-bsd.c
+	ecp.c demand.c auth.c options.c utils.c sys-bsd.c eap.c tty.c
 MAN=	pppd.cat8
 MAN8=	pppd.8
 BINMODE=4555