Replace the original host WEP implementation with the one in OpenBSD

(apparently by markus@, at least committed by him).  This has the
advantage of not using the bad IV's from Fluhrer/Mantin/Shamir as well
as bringing the drivers a little closer together.

Also use a few constants in place of magic numbers in one place.

Obtained from: OpenBSD 1.25, 1.28, 1.36, 1.38, 1.42

2 files changed, 130 insertions, 146 deletions

diff --git a/sys/dev/wi/if_wi.c b/sys/dev/wi/if_wi.c
index 3adecc1..f7e656e 100644
--- a/sys/dev/wi/if_wi.c
+++ b/sys/dev/wi/if_wi.c
@@ -2004,158 +2004,140 @@ wi_init(xsc)
 	return;
 }
 
-#ifdef WI_HOSTAP
-
-/*
- * Host encryption code: Transmits are broken in Host AP mode when WEP is
- * enabled.  So, we disable TX encryption and manually encrypt it here.
- */
-
-static u_int32_t
-wi_next_crc32(u_int32_t crc32, u_int8_t byte)
-{
-	/* Thanks again, RFC 1662. */
-	static u_int32_t fcstab_32[] = {
-		0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
-		0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
-		0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
-		0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
-		0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
-		0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
-		0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
-		0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
-		0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
-		0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
-		0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
-		0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
-		0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
-		0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
-		0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
-		0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
-		0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
-		0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
-		0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
-		0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
-		0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
-		0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
-		0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
-		0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
-		0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
-		0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
-		0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
-		0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
-		0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
-		0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
-		0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
-		0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
-		0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
-		0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
-		0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
-		0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
-		0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
-		0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
-		0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
-		0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
-		0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
-		0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
-		0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
-		0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
-		0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
-		0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
-		0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
-		0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
-		0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
-		0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
-		0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
-		0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
-		0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
-		0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
-		0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
-		0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
-		0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
-		0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
-		0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
-		0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
-		0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
-		0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
-		0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
-		0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
-	};
-
-	return (crc32>>8) ^ fcstab_32[(u_int8_t)(byte ^ crc32)];
-}
-
+static u_int32_t crc32_tab[] = {
+	0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
+	0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
+	0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
+	0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
+	0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
+	0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
+	0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
+	0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
+	0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
+	0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
+	0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
+	0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
+	0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
+	0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
+	0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
+	0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
+	0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
+	0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
+	0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
+	0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
+	0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
+	0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
+	0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
+	0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
+	0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
+	0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
+	0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
+	0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
+	0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
+	0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
+	0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
+	0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
+	0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
+	0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
+	0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
+	0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
+	0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
+	0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
+	0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
+	0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
+	0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
+	0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
+	0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
+	0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
+	0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
+	0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
+	0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
+	0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
+	0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
+	0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
+	0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
+	0x2d02ef8dL
+};
 
-static __inline void
-SWAP(u_int8_t *pa, u_int8_t *pb)
-{
-	u_int8_t c;
-	c = *pa;
-	*pa = *pb;
-	*pb = c;
-}
+#define RC4STATE 256
+#define RC4KEYLEN 16
+#define RC4SWAP(x,y) \
+    do { u_int8_t t = state[x]; state[x] = state[y]; state[y] = t; } while(0)
 
 static void
 wi_do_hostencrypt(struct wi_softc *sc, caddr_t buf, int len)
 {
-	int 		i;
-	u_int32_t	crc32;
-	u_int8_t 	k[16];
-	u_int8_t	state[256];
-	u_int8_t	x, y;
-	int		keylen;
-
-	keylen = (sc->wi_keys.wi_keys[sc->wi_tx_key].wi_keylen>5) ? 16:8;
-
-	/* Create ICV/key concatenation. */
-	k[0] = sc->wi_icv >> 16;
-	k[1] = sc->wi_icv >> 8;
-	k[2] = sc->wi_icv;
-	for (i=3; i<keylen; i++)
-		k[i] = sc->wi_keys.wi_keys[sc->wi_tx_key].wi_keydat[i-3];
-
-	/* Insert ICV in packet. */
-	buf[0] = k[0];
-	buf[1] = k[1];
-	buf[2] = k[2];
-	buf[3] = (sc->wi_tx_key<<6);
-	++sc->wi_icv;
-
-	/* Initialize key. */
-	for (i=0; i<256; i++)
-		state[i]=i;
-	x=0;
-	y=0;
-	for (i=0; i<256; i++) {
-		y = (k[x]+state[i]+y);
-		SWAP(&state[i], &state[y]);
-		x = (x+1) & (keylen-1);
-	}
-
-	/* Start encrypting. */
-	x=0;
-	y=0;
-	crc32=0xffffffff;
-	for (i=0; i<len; i++) {
-		x++;
-		y = state[x]+y;
-		SWAP(&state[x], &state[y]);
-		crc32 = wi_next_crc32(crc32, buf[i+4]);
-		buf[i+4] ^= state[ (u_int8_t)(state[x] + state[y]) ];
-	}
-
-	/* Append CRC-32, encrypt it too. */
-	crc32 ^= 0xffffffff;
-	for (i=0; i<4; i++) {
-		x++;
-		y = state[x]+y;
-		SWAP(&state[x], &state[y]);
-		buf[i+len+4] = crc32;
-		crc32 >>= 8;
-		buf[i+len+4] ^= state[ (u_int8_t)(state[x] + state[y]) ];
+	u_int32_t i, crc, klen;
+	u_int8_t state[RC4STATE], key[RC4KEYLEN];
+	u_int8_t x, y, *dat;
+
+	if (!sc->wi_icv_flag) {
+		sc->wi_icv = arc4random();
+		sc->wi_icv_flag++;
+        } else
+		sc->wi_icv++;
+	/*
+	 * Skip 'bad' IVs from Fluhrer/Mantin/Shamir:
+	 * (B, 255, N) with 3 <= B < 8
+	 */
+	if (sc->wi_icv >= 0x03ff00 &&
+            (sc->wi_icv & 0xf8ff00) == 0x00ff00)
+                sc->wi_icv += 0x000100;
+
+	/* prepend 24bit IV to tx key, byte order does not matter */
+	key[0] = sc->wi_icv >> 16;
+	key[1] = sc->wi_icv >> 8;
+	key[2] = sc->wi_icv;
+
+	klen = sc->wi_keys.wi_keys[sc->wi_tx_key].wi_keylen +
+	    IEEE80211_WEP_IVLEN;
+	klen = (klen >= RC4KEYLEN) ? RC4KEYLEN : RC4KEYLEN/2;
+	bcopy((char *)&sc->wi_keys.wi_keys[sc->wi_tx_key].wi_keydat,
+	    (char *)key + IEEE80211_WEP_IVLEN, klen - IEEE80211_WEP_IVLEN);
+
+	/* rc4 keysetup */
+	x = y = 0;
+	for (i = 0; i < RC4STATE; i++)
+		state[i] = i;
+	for (i = 0; i < RC4STATE; i++) {
+		y = (key[x] + state[i] + y) % RC4STATE;
+		RC4SWAP(i, y);
+		x = (x + 1) % klen;
+	}
+
+	/* output: IV, tx keyid, rc4(data), rc4(crc32(data)) */
+	dat = buf;
+	dat[0] = key[0];
+	dat[1] = key[1];
+	dat[2] = key[2];
+	dat[3] = sc->wi_tx_key << 6;		/* pad and keyid */
+	dat += 4;
+
+	/* compute rc4 over data, crc32 over data */
+	crc = ~0;
+	x = y = 0;
+	for (i = 0; i < len; i++) {
+		x = (x + 1) % RC4STATE;
+		y = (state[x] + y) % RC4STATE;
+		RC4SWAP(x, y);
+		crc = crc32_tab[(crc ^ dat[i]) & 0xff] ^ (crc >> 8);
+		dat[i] ^= state[(state[x] + state[y]) % RC4STATE];
+	}
+	crc = ~crc;
+	dat += len;
+
+	/* append little-endian crc32 and encrypt */
+	dat[0] = crc;
+	dat[1] = crc >> 8;
+	dat[2] = crc >> 16;
+	dat[3] = crc >> 24;
+	for (i = 0; i < IEEE80211_WEP_CRCLEN; i++) {
+		x = (x + 1) % RC4STATE;
+		y = (state[x] + y) % RC4STATE;
+		RC4SWAP(x, y);
+		dat[i] ^= state[(state[x] + state[y]) % RC4STATE];
 	}
 }
-#endif /* WI_HOSTAP */
 
 static void
 wi_start(ifp)
@@ -2248,7 +2230,8 @@ nextpkt:
 			    (caddr_t)&sc->wi_txbuf[12]);
 			wi_do_hostencrypt(sc, &sc->wi_txbuf[0],
 			    tx_frame.wi_dat_len);
-			tx_frame.wi_dat_len += 8;
+			tx_frame.wi_dat_len += IEEE80211_WEP_IVLEN +
+			    IEEE80211_WEP_KIDLEN + IEEE80211_WEP_CRCLEN;
 			wi_write_data(sc, id, 0, (caddr_t)&tx_frame,
 			    sizeof(struct wi_frame));
 			wi_write_data(sc, id, WI_802_11_OFFSET_RAW,
diff --git a/sys/dev/wi/if_wivar.h b/sys/dev/wi/if_wivar.h
index cc1eaf8..777f3ab 100644
--- a/sys/dev/wi/if_wivar.h
+++ b/sys/dev/wi/if_wivar.h
@@ -160,6 +160,7 @@ struct wi_softc	{
 #ifdef WI_HOSTAP
 	struct wihap_info	wi_hostap_info;
 	u_int32_t		wi_icv;
+	int			wi_icv_flag;
 #endif
 	struct callout_handle	wi_stat_ch;
 	struct mtx		wi_mtx;