From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Domsch Subject: RFC: [1/2] PPP MPPE module Date: Fri, 18 Jun 2004 11:12:42 -0500 Sender: netdev-bounce@oss.sgi.com Message-ID: <20040618161242.GG19269@lists.us.dell.com> References: <20040618161001.GE19269@lists.us.dell.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="NPukt5Otb9an/u20" Return-path: To: netdev@oss.sgi.com, pptpclient-devel@lists.sourceforge.net Content-Disposition: inline In-Reply-To: <20040618161001.GE19269@lists.us.dell.com> Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org --NPukt5Otb9an/u20 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jun 18, 2004 at 11:10:01AM -0500, Matt Domsch wrote: > Following two emails each contain patches. Of course, that subject should have been [0,1,2/2], not of 3. > 2) minimal touches to Makefile, KConfig, ppp_generic.c, and > include/linux/ppp-comp.h --=20 Matt Domsch Sr. Software Engineer, Lead Engineer Dell Linux Solutions linux.dell.com & www.dell.com/linux Linux on Dell mailing lists @ http://lists.us.dell.com =3D=3D=3D=3D=3D drivers/net/Kconfig 1.75 vs edited =3D=3D=3D=3D=3D --- 1.75/drivers/net/Kconfig 2004-06-02 15:04:38 -05:00 +++ edited/drivers/net/Kconfig 2004-06-18 09:48:16 -05:00 @@ -2410,6 +2410,12 @@ module; it is called bsd_comp and will show up in the directory modules once you have said "make modules". If unsure, say N. =20 +config PPP_MPPE + tristate "PPP MPPE compression (encryption)" + depends on PPP + ---help--- + Support for the MPPE Encryption protocol. + config PPPOE tristate "PPP over Ethernet (EXPERIMENTAL)" depends on EXPERIMENTAL && PPP =3D=3D=3D=3D=3D drivers/net/Makefile 1.79 vs edited =3D=3D=3D=3D=3D --- 1.79/drivers/net/Makefile 2004-05-22 12:13:08 -05:00 +++ edited/drivers/net/Makefile 2004-06-18 10:22:41 -05:00 @@ -100,6 +100,7 @@ obj-$(CONFIG_PPP_SYNC_TTY) +=3D ppp_synctty.o obj-$(CONFIG_PPP_DEFLATE) +=3D ppp_deflate.o obj-$(CONFIG_PPP_BSDCOMP) +=3D bsd_comp.o +obj-$(CONFIG_PPP_MPPE) +=3D ppp_mppe.o obj-$(CONFIG_PPPOE) +=3D pppox.o pppoe.o =20 obj-$(CONFIG_SLIP) +=3D slip.o =3D=3D=3D=3D=3D drivers/net/ppp_generic.c 1.45 vs edited =3D=3D=3D=3D=3D --- 1.45/drivers/net/ppp_generic.c 2004-04-09 18:21:06 -05:00 +++ edited/drivers/net/ppp_generic.c 2004-06-18 09:47:10 -05:00 @@ -1066,8 +1066,15 @@ /* try to do packet compression */ if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state !=3D 0 && proto !=3D PPP_LCP && proto !=3D PPP_CCP) { - new_skb =3D alloc_skb(ppp->dev->mtu + ppp->dev->hard_header_len, - GFP_ATOMIC); + int new_skb_size =3D ppp->dev->mtu + ppp->dev->hard_header= _len; + int compressor_skb_size =3D ppp->dev->mtu + PPP_HDRLEN; + + if (ppp->xcomp->compress_proto =3D=3D CI_MPPE) { + /* CCP [must have] reduced MTU by MPPE_PAD. */ + new_skb_size +=3D MPPE_PAD; + compressor_skb_size +=3D MPPE_PAD; + } + new_skb =3D alloc_skb(new_skb_size, GFP_ATOMIC); if (new_skb =3D=3D 0) { printk(KERN_ERR "PPP: no memory (comp pkt)\n"); goto drop; @@ -1079,15 +1086,27 @@ /* compressor still expects A/C bytes in hdr */ len =3D ppp->xcomp->compress(ppp->xc_state, skb->data - 2, new_skb->data, skb->len + 2, - ppp->dev->mtu + PPP_HDRLEN); + compressor_skb_size); if (len > 0 && (ppp->flags & SC_CCP_UP)) { kfree_skb(skb); skb =3D new_skb; skb_put(skb, len); skb_pull(skb, 2); /* pull off A/C bytes */ - } else { + } else if (len =3D=3D 0) { /* didn't compress, or CCP not up yet */ kfree_skb(new_skb); + } else { + /* + * (len < 0) + * MPPE requires that we do not send unencrypted + * frames. The compressor will return -1 if we + * should drop the frame. We cannot simply test + * the compress_proto because MPPE and MPPC share + * the same number. + */ + printk(KERN_ERR "ppp: compressor dropped pkt\n"); + kfree_skb(new_skb); + goto drop; } } =20 @@ -1596,7 +1615,7 @@ goto err; =20 if (proto =3D=3D PPP_COMP) { - ns =3D dev_alloc_skb(ppp->mru + PPP_HDRLEN); + ns =3D dev_alloc_skb(ppp->mru + 128 + PPP_HDRLEN); if (ns =3D=3D 0) { printk(KERN_ERR "ppp_decompress_frame: no memory\n"); goto err; =3D=3D=3D=3D=3D include/linux/ppp-comp.h 1.4 vs edited =3D=3D=3D=3D=3D --- 1.4/include/linux/ppp-comp.h 2003-08-07 18:57:19 -05:00 +++ edited/include/linux/ppp-comp.h 2004-06-18 09:46:32 -05:00 @@ -191,6 +191,100 @@ #define DEFLATE_CHK_SEQUENCE 0 =20 /* + * Definitions for MPPE. + */ + +#define CI_MPPE 18 /* config option for MPPE */ +#define CILEN_MPPE 6 /* length of config option */ + +#define MPPE_PAD 8 /* MPPE growth per frame */ +#define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ + +/* option bits for ccp_options.mppe */ +#define MPPE_OPT_40 0x01 /* 40 bit */ +#define MPPE_OPT_128 0x02 /* 128 bit */ +#define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ +/* unsupported opts */ +#define MPPE_OPT_56 0x08 /* 56 bit */ +#define MPPE_OPT_MPPC 0x10 /* MPPC compression */ +#define MPPE_OPT_D 0x20 /* Unknown */ +#define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) +#define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were s= et */ + +/* + * This is not nice ... the alternative is a bitfield struct though. + * And unfortunately, we cannot share the same bits for the option + * names above since C and H are the same bit. We could do a u_int32 + * but then we have to do a htonl() all the time and/or we still need + * to know which octet is which. + */ +#define MPPE_C_BIT 0x01 /* MPPC */ +#define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ +#define MPPE_L_BIT 0x20 /* 40-bit */ +#define MPPE_S_BIT 0x40 /* 128-bit */ +#define MPPE_M_BIT 0x80 /* 56-bit, not supported */ +#define MPPE_H_BIT 0x01 /* Stateless (in a different byte) = */ + +/* Does not include H bit; used for least significant octet only. */ +#define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_= BIT) + +/* Build a CI from mppe opts (see RFC 3078) */ +#define MPPE_OPTS_TO_CI(opts, ci) \ + do { \ + u_char *ptr =3D ci; /* u_char[4] */ \ + \ + /* H bit */ \ + if (opts & MPPE_OPT_STATEFUL) \ + *ptr++ =3D 0x0; \ + else \ + *ptr++ =3D MPPE_H_BIT; \ + *ptr++ =3D 0; \ + *ptr++ =3D 0; \ + \ + /* S,L bits */ \ + *ptr =3D 0; \ + if (opts & MPPE_OPT_128) \ + *ptr |=3D MPPE_S_BIT; \ + if (opts & MPPE_OPT_40) \ + *ptr |=3D MPPE_L_BIT; \ + /* M,D,C bits not supported */ \ + } while (/* CONSTCOND */ 0) + +/* The reverse of the above */ +#define MPPE_CI_TO_OPTS(ci, opts) \ + do { \ + u_char *ptr =3D ci; /* u_char[4] */ \ + \ + opts =3D 0; \ + \ + /* H bit */ \ + if (!(ptr[0] & MPPE_H_BIT)) \ + opts |=3D MPPE_OPT_STATEFUL; \ + \ + /* S,L bits */ \ + if (ptr[3] & MPPE_S_BIT) \ + opts |=3D MPPE_OPT_128; \ + if (ptr[3] & MPPE_L_BIT) \ + opts |=3D MPPE_OPT_40; \ + \ + /* M,D,C bits */ \ + if (ptr[3] & MPPE_M_BIT) \ + opts |=3D MPPE_OPT_56; \ + if (ptr[3] & MPPE_D_BIT) \ + opts |=3D MPPE_OPT_D; \ + if (ptr[3] & MPPE_C_BIT) \ + opts |=3D MPPE_OPT_MPPC; \ + \ + /* Other bits */ \ + if (ptr[0] & ~MPPE_H_BIT) \ + opts |=3D MPPE_OPT_UNKNOWN; \ + if (ptr[1] || ptr[2]) \ + opts |=3D MPPE_OPT_UNKNOWN; \ + if (ptr[3] & ~MPPE_ALL_BITS) \ + opts |=3D MPPE_OPT_UNKNOWN; \ + } while (/* CONSTCOND */ 0) + +/* * Definitions for other, as yet unsupported, compression methods. */ =20 --NPukt5Otb9an/u20 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (GNU/Linux) iD8DBQFA0xR6Iavu95Lw/AkRAjOKAJkBJWyuu6vQLBzIaLNuprukHDOHIgCgiVv9 3l+eLzGgZl982DqgnqLz03A= =AWiM -----END PGP SIGNATURE----- --NPukt5Otb9an/u20--