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Diffstat (limited to 'drivers/staging/ks7010/michael_mic.c')
-rw-r--r--drivers/staging/ks7010/michael_mic.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/staging/ks7010/michael_mic.c b/drivers/staging/ks7010/michael_mic.c
new file mode 100644
index 000000000000..e14c109b3cab
--- /dev/null
+++ b/drivers/staging/ks7010/michael_mic.c
@@ -0,0 +1,139 @@
+/*
+ * Driver for KeyStream wireless LAN
+ *
+ * Copyright (C) 2005-2008 KeyStream Corp.
+ * Copyright (C) 2009 Renesas Technology Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+#include "michael_mic.h"
+
+// Rotation functions on 32 bit values
+#define ROL32( A, n ) ( ((A) << (n)) | ( ((A)>>(32-(n))) & ( (1UL << (n)) - 1 ) ) )
+#define ROR32( A, n ) ROL32( (A), 32-(n) )
+// Convert from Byte[] to UInt32 in a portable way
+#define getUInt32( A, B ) (uint32_t)(A[B+0] << 0) + (A[B+1] << 8) + (A[B+2] << 16) + (A[B+3] << 24)
+
+// Convert from UInt32 to Byte[] in a portable way
+#define putUInt32( A, B, C ) A[B+0] = (uint8_t) (C & 0xff); \
+ A[B+1] = (uint8_t) ((C>>8) & 0xff); \
+ A[B+2] = (uint8_t) ((C>>16) & 0xff); \
+ A[B+3] = (uint8_t) ((C>>24) & 0xff)
+
+// Reset the state to the empty message.
+#define MichaelClear( A ) A->L = A->K0; \
+ A->R = A->K1; \
+ A->nBytesInM = 0;
+
+static
+void MichaelInitializeFunction(struct michel_mic_t *Mic, uint8_t * key)
+{
+ // Set the key
+ Mic->K0 = getUInt32(key, 0);
+ Mic->K1 = getUInt32(key, 4);
+
+ //clear();
+ MichaelClear(Mic);
+}
+
+#define MichaelBlockFunction(L, R) \
+do{ \
+ R ^= ROL32( L, 17 ); \
+ L += R; \
+ R ^= ((L & 0xff00ff00) >> 8) | ((L & 0x00ff00ff) << 8); \
+ L += R; \
+ R ^= ROL32( L, 3 ); \
+ L += R; \
+ R ^= ROR32( L, 2 ); \
+ L += R; \
+}while(0)
+
+static
+void MichaelAppend(struct michel_mic_t *Mic, uint8_t * src, int nBytes)
+{
+ int addlen;
+ if (Mic->nBytesInM) {
+ addlen = 4 - Mic->nBytesInM;
+ if (addlen > nBytes)
+ addlen = nBytes;
+ memcpy(&Mic->M[Mic->nBytesInM], src, addlen);
+ Mic->nBytesInM += addlen;
+ src += addlen;
+ nBytes -= addlen;
+
+ if (Mic->nBytesInM < 4)
+ return;
+
+ Mic->L ^= getUInt32(Mic->M, 0);
+ MichaelBlockFunction(Mic->L, Mic->R);
+ Mic->nBytesInM = 0;
+ }
+
+ while (nBytes >= 4) {
+ Mic->L ^= getUInt32(src, 0);
+ MichaelBlockFunction(Mic->L, Mic->R);
+ src += 4;
+ nBytes -= 4;
+ }
+
+ if (nBytes > 0) {
+ Mic->nBytesInM = nBytes;
+ memcpy(Mic->M, src, nBytes);
+ }
+}
+
+static
+void MichaelGetMIC(struct michel_mic_t *Mic, uint8_t * dst)
+{
+ uint8_t *data = Mic->M;
+ switch (Mic->nBytesInM) {
+ case 0:
+ Mic->L ^= 0x5a;
+ break;
+ case 1:
+ Mic->L ^= data[0] | 0x5a00;
+ break;
+ case 2:
+ Mic->L ^= data[0] | (data[1] << 8) | 0x5a0000;
+ break;
+ case 3:
+ Mic->L ^= data[0] | (data[1] << 8) | (data[2] << 16) |
+ 0x5a000000;
+ break;
+ }
+ MichaelBlockFunction(Mic->L, Mic->R);
+ MichaelBlockFunction(Mic->L, Mic->R);
+ // The appendByte function has already computed the result.
+ putUInt32(dst, 0, Mic->L);
+ putUInt32(dst, 4, Mic->R);
+
+ // Reset to the empty message.
+ MichaelClear(Mic);
+}
+
+void MichaelMICFunction(struct michel_mic_t *Mic, uint8_t * Key,
+ uint8_t * Data, int Len, uint8_t priority,
+ uint8_t * Result)
+{
+ uint8_t pad_data[4] = { priority, 0, 0, 0 };
+ // Compute the MIC value
+ /*
+ * IEEE802.11i page 47
+ * Figure 43g TKIP MIC processing format
+ * +--+--+--------+--+----+--+--+--+--+--+--+--+--+
+ * |6 |6 |1 |3 |M |1 |1 |1 |1 |1 |1 |1 |1 | Octet
+ * +--+--+--------+--+----+--+--+--+--+--+--+--+--+
+ * |DA|SA|Priority|0 |Data|M0|M1|M2|M3|M4|M5|M6|M7|
+ * +--+--+--------+--+----+--+--+--+--+--+--+--+--+
+ */
+ MichaelInitializeFunction(Mic, Key);
+ MichaelAppend(Mic, (uint8_t *) Data, 12); /* |DA|SA| */
+ MichaelAppend(Mic, pad_data, 4); /* |Priority|0|0|0| */
+ MichaelAppend(Mic, (uint8_t *) (Data + 12), Len - 12); /* |Data| */
+ MichaelGetMIC(Mic, Result);
+}