Initial implementation.

2 files changed, 534 insertions, 0 deletions

diff --git a/rijndael.c b/rijndael.c
new file mode 100644
index 0000000..e34c13d
--- /dev/null
+++ b/rijndael.c
@@ -0,0 +1,460 @@
+/*
+ * Highly portable ANSI C implementation of Rijndael cipher.
+ * Written by Kaz Kylheku.
+ */
+
+#include <string.h>
+#include <assert.h>
+#include "rijndael.h"
+
+#define numrows_to_blocksize(N) (4 * (N))
+#define max(a, b) ((a) > (b) ? (a) : (b))
+
+static int log_table[256];
+static int antilog_table[256];
+static int s_box[256];
+static int s_box_inverse[256];
+static int rcon[30];
+
+static int
+multiply(int a, int b)
+{
+	if (a != 0 && b != 0)
+		return antilog_table[(log_table[a] + log_table[b]) % 255];
+	return 0;
+}
+
+static void
+key_add(rijn_block_t *out, rijn_block_t *in, rijn_block_t *roundkey, int numrows)
+{
+	unsigned char *flat_out = (unsigned char *) out;
+	const unsigned char *flat_in = (unsigned char *) in;
+	const unsigned char *flat_rk = (unsigned char *) roundkey;
+	int numbytes = numrows_to_blocksize(numrows);
+
+	while (numbytes-- > 0)
+		*flat_out++ = *flat_in++ ^ *flat_rk++;
+}
+
+static void
+shift_column_routine(rijn_block_t *block, rijn_size_t numrows, int inverse)
+{
+	static int shifts[2][3][4] = {
+		{
+			{ 0, 1, 2, 3 },	/* shifts for 128 bit block */
+			{ 0, 1, 2, 3 }, /* shifts for 192 bit block */
+			{ 0, 1, 3, 4 }, /* shifts for 256 bit block */
+		}, 
+		{
+			{ 0, 3, 2, 1 }, /* inverse shifts for 128 bit block */
+			{ 0, 5, 4, 3 }, /* inverse shifts for 192 bit block */ 
+			{ 0, 7, 5, 4 }, /* inverse shifts for 256 bit block */
+		}
+	};
+
+	rijn_block_t temp;
+	int shift_index = (numrows - 4) / 2;
+	int i;
+	int *shift_select;
+
+	assert (numrows == rijn_128 || numrows == rijn_192 || numrows == rijn_256);
+	assert (shift_index >= 0 && shift_index < 3);
+	assert (inverse == 0 || inverse == 1);
+
+	shift_select = shifts[inverse][shift_index];
+
+	/*
+	 * Create temporary block, with the columns shifted by the amount
+	 * from the table. The switch is used in order to reduce the
+	 * modulus to a constant.
+	 */
+
+	switch (numrows) {
+	case rijn_128:
+		for (i = 0; i < numrows; i++) {
+			temp[i][0] = (*block)[i][0];
+			temp[i][1] = (*block)[(i + shift_select[1]) % rijn_128][1];
+			temp[i][2] = (*block)[(i + shift_select[2]) % rijn_128][2];
+			temp[i][3] = (*block)[(i + shift_select[3]) % rijn_128][3];
+		}
+		break;
+	case rijn_192:
+		for (i = 0; i < numrows; i++) {
+			temp[i][0] = (*block)[i][0];
+			temp[i][1] = (*block)[(i + shift_select[1]) % rijn_192][1];
+			temp[i][2] = (*block)[(i + shift_select[2]) % rijn_192][2];
+			temp[i][3] = (*block)[(i + shift_select[3]) % rijn_192][3];
+		}
+		break;
+	case rijn_256:
+		for (i = 0; i < numrows; i++) {
+			temp[i][0] = (*block)[i][0];
+			temp[i][1] = (*block)[(i + shift_select[1]) % rijn_256][1];
+			temp[i][2] = (*block)[(i + shift_select[2]) % rijn_256][2];
+			temp[i][3] = (*block)[(i + shift_select[3]) % rijn_256][3];
+		}
+		break;
+	}
+
+	/*
+	 * Block is ready, just copy it over
+	 */
+
+	memcpy(block, &temp, numrows_to_blocksize(numrows));;
+}
+
+static void
+shift_column(rijn_block_t *block, rijn_size_t numrows)
+{
+	shift_column_routine(block, numrows, 0);
+}
+
+static void
+shift_column_inverse(rijn_block_t *block, rijn_size_t numrows)
+{
+	shift_column_routine(block, numrows, 1);
+}
+
+static void
+substitute(rijn_block_t *block, int *box, int numrows)
+{
+	unsigned char *flat_block = (unsigned char *) block;
+	int numbytes = numrows_to_blocksize(numrows);
+
+	while (numbytes-- > 0)
+		flat_block[numbytes] = box[flat_block[numbytes]];
+}
+
+static void
+mix_row(rijn_block_t *block, rijn_size_t numrows)
+{
+	rijn_block_t temp;
+	int i, j;
+
+	for (j = 0; j < numrows; j++) {
+		for (i = 0; i < 4; i++) {
+			temp[j][i] = multiply(2,(*block)[j][i])
+				       ^ multiply(3,(*block)[j][(i + 1) % 4])
+				       ^            (*block)[j][(i + 2) % 4]
+				       ^            (*block)[j][(i + 3) % 4];
+		}
+	}
+
+	memcpy(block, &temp, numrows_to_blocksize(numrows));
+}
+
+static void
+mix_row_inverse(rijn_block_t *block, rijn_size_t numrows)
+{
+	rijn_block_t temp;
+	int i, j;
+
+	for (j = 0; j < numrows; j++) {
+		for (i = 0; i < 4; i++) {
+			temp[j][i] = multiply(14,(*block)[j][i])
+				       ^ multiply(11,(*block)[j][(i + 1) % 4])
+				       ^ multiply(13,(*block)[j][(i + 2) % 4])
+				       ^ multiply( 9,(*block)[j][(i + 3) % 4]);
+		}
+	}
+
+	memcpy(block, &temp, numrows_to_blocksize(numrows));
+}
+
+void 
+rijn_param_init(rijn_param_t *param, rijn_size_t blocksize, rijn_size_t keysize)
+{
+	assert (blocksize == rijn_128 || blocksize == rijn_192 || blocksize == rijn_256);
+	assert (keysize == rijn_128 || keysize == rijn_192 || keysize == rijn_256);
+
+	param->rijn_blockrows = blocksize;
+	param->rijn_keyrows = keysize;
+}
+
+void 
+rijn_sched_key(rijn_keysched_t *sched, rijn_key_t *key, const rijn_param_t *param)
+{
+	rijn_size_t keyrows = param->rijn_keyrows;
+	rijn_size_t blockrows = param->rijn_blockrows;
+	rijn_key_t temp_key;
+	int keybytes = numrows_to_blocksize(keyrows);
+	int row, i, nrounds = 0, rcon_index = 0;
+
+	sched->rijn_param = *param;
+	switch (max(keyrows, blockrows)) {
+	case rijn_128:
+		nrounds = sched->rijn_nrounds = 10;
+		break;
+	case rijn_192:
+		nrounds = sched->rijn_nrounds = 12;
+		break;
+	case rijn_256:
+		nrounds = sched->rijn_nrounds = 14;
+		break;
+	}
+
+	assert (nrounds != 0);
+
+	memcpy(&temp_key, key, keybytes);
+
+	for (row = 0; row < keyrows; row++) {
+		sched->rijn_roundkey[row / blockrows][row % blockrows][0] = temp_key[row][0];
+		sched->rijn_roundkey[row / blockrows][row % blockrows][1] = temp_key[row][1];
+		sched->rijn_roundkey[row / blockrows][row % blockrows][2] = temp_key[row][2];
+		sched->rijn_roundkey[row / blockrows][row % blockrows][3] = temp_key[row][3];
+	}
+
+	while (row < (nrounds + 1) * blockrows) {
+		temp_key[0][0] ^= s_box[temp_key[keyrows-1][1]];
+		temp_key[0][1] ^= s_box[temp_key[keyrows-1][2]];
+		temp_key[0][2] ^= s_box[temp_key[keyrows-1][3]];
+		temp_key[0][3] ^= s_box[temp_key[keyrows-1][0]];
+
+		temp_key[0][0] ^= rcon[rcon_index++];
+
+		if (keyrows == 8) {
+			for (i = 1; i < keyrows / 2; i++) {
+				temp_key[i][0] ^= temp_key[i-1][0];
+				temp_key[i][1] ^= temp_key[i-1][1];
+				temp_key[i][2] ^= temp_key[i-1][2];
+				temp_key[i][3] ^= temp_key[i-1][3];
+			}
+			temp_key[0][i] ^= s_box[temp_key[i-1][0]];
+			temp_key[1][i] ^= s_box[temp_key[i-1][1]];
+			temp_key[2][i] ^= s_box[temp_key[i-1][2]];
+			temp_key[3][i] ^= s_box[temp_key[i-1][3]];
+			for (i++; i < keyrows; i++) {
+				temp_key[i][0] ^= temp_key[i-1][0];
+				temp_key[i][1] ^= temp_key[i-1][1];
+				temp_key[i][2] ^= temp_key[i-1][2];
+				temp_key[i][3] ^= temp_key[i-1][3];
+			}
+		} else {
+			assert (keyrows != 8);
+			for (i = 1; i < keyrows; i++) {
+				temp_key[i][0] ^= temp_key[i-1][0];
+				temp_key[i][1] ^= temp_key[i-1][1];
+				temp_key[i][2] ^= temp_key[i-1][2];
+				temp_key[i][3] ^= temp_key[i-1][3];
+			}
+		}
+
+		for (i = 0; i < keyrows && row < (nrounds + 1) * blockrows; i++, row++) {
+			sched->rijn_roundkey[row / blockrows][row % blockrows][0] = temp_key[i][0];
+			sched->rijn_roundkey[row / blockrows][row % blockrows][1] = temp_key[i][1];
+			sched->rijn_roundkey[row / blockrows][row % blockrows][2] = temp_key[i][2];
+			sched->rijn_roundkey[row / blockrows][row % blockrows][3] = temp_key[i][3];
+		}
+	}
+}
+
+void 
+rijn_encrypt(rijn_keysched_t *sched, unsigned char *out, const unsigned char *in)
+{
+	rijn_size_t blockrows = sched->rijn_param.rijn_blockrows;
+	int round, nrounds = sched->rijn_nrounds;
+
+	rijn_block_t *out_block = (rijn_block_t *) out;
+	rijn_block_t *in_block = (rijn_block_t *) in;
+
+	key_add(out_block, in_block, &sched->rijn_roundkey[0], blockrows);
+
+	for (round = 1; round < nrounds; round++) {
+		substitute(out_block, s_box, blockrows);
+		shift_column(out_block, blockrows);
+		mix_row(out_block, blockrows);
+		key_add(out_block, out_block, &sched->rijn_roundkey[round], blockrows);
+	}
+
+	substitute(out_block, s_box, blockrows);
+	shift_column(out_block, blockrows);
+	key_add(out_block, out_block, &sched->rijn_roundkey[round], blockrows);
+}
+
+void 
+rijn_decrypt(rijn_keysched_t *sched, unsigned char *out, const unsigned char *in)
+{
+	rijn_size_t blockrows = sched->rijn_param.rijn_blockrows;
+	int round, nrounds = sched->rijn_nrounds;
+
+	rijn_block_t *out_block = (rijn_block_t *) out;
+	rijn_block_t *in_block = (rijn_block_t *) in;
+
+	key_add(out_block, in_block, &sched->rijn_roundkey[nrounds], blockrows);
+	substitute(out_block, s_box_inverse, blockrows);
+	shift_column_inverse(out_block, blockrows);
+
+	for (round = nrounds - 1; round > 0; round--) {
+		key_add(out_block, out_block, &sched->rijn_roundkey[round], blockrows);
+		mix_row_inverse(out_block, blockrows);
+		substitute(out_block, s_box_inverse, blockrows);
+		shift_column_inverse(out_block, blockrows);
+	}
+
+	assert (round == 0);
+	key_add(out_block, out_block, &sched->rijn_roundkey[round], blockrows);
+}
+
+static 
+void xor_mem(unsigned char *dest, const unsigned char *a, 
+		const unsigned char *b, size_t n)
+{
+	while (n--)
+		*dest++ = *a++ ^ *b++;
+}
+
+void 
+rijn_cbc_encrypt(rijn_keysched_t *sched, unsigned char *iv, unsigned char *out, 
+		const unsigned char *in, size_t nblocks)
+{
+	unsigned char *ivec = iv;
+	size_t blocksize = numrows_to_blocksize(sched->rijn_param.rijn_blockrows);
+	size_t i, nbytes = nblocks * blocksize;
+
+	for (i = 0; i < nbytes; i += blocksize) {
+		xor_mem(out + i, in + i, ivec, blocksize);
+		rijn_encrypt(sched, out + i, out + i);
+		ivec = out + i;
+	}
+
+	memcpy(iv, ivec, blocksize);
+}
+
+void 
+rijn_cbc_decrypt(rijn_keysched_t *sched, unsigned char *iv, unsigned char *out,
+		const unsigned char *in, size_t nblocks)
+{
+	rijn_block_t iv_save;
+	size_t blocksize = numrows_to_blocksize(sched->rijn_param.rijn_blockrows);
+	size_t i, nbytes = nblocks * blocksize;
+
+	if (nblocks > 0) {
+		memcpy(&iv_save, in + nbytes - blocksize, blocksize);
+
+		for (i = nbytes - blocksize; i < nbytes; i -= blocksize) {
+			const unsigned char *ivec = (i > 0) ? in + i - blocksize : iv;
+			rijn_decrypt(sched, out + i, in + i);
+			xor_mem(out + i, out + i, ivec, blocksize);
+		}
+
+		memcpy(iv, &iv_save, blocksize);
+	}
+}
+
+#ifdef RIJN_TEST
+
+#include <stdio.h>
+
+static void hex_dump(const unsigned char *data, size_t size, FILE *stream)
+{
+	while (size--)
+		fprintf(stream, "%02X", (unsigned int) *data++);
+}
+
+int main(void)
+{
+	static rijn_param_t param = RIJN_PARAM_INITIALIZER(rijn_128, rijn_192);
+#if 0
+	rijn_key_t key = { 0x00, 0x01, 0x02, 0x03, 0x05, 0x06, 0x07, 0x08, 0x0A,
+		0x0B, 0x0C, 0x0D, 0x0F, 0x10, 0x11, 0x12 };
+#else
+	rijn_key_t key = { { 0x80 } };
+#endif
+	rijn_keysched_t sched = { 0 };
+	unsigned char plaintext[32] = { 0 };
+	unsigned char ciphertext[32] = { 0 };
+
+	rijn_sched_key(&sched, &key, &param);
+	rijn_encrypt(&sched, ciphertext, plaintext);
+	hex_dump(ciphertext, 16, stdout);
+	putchar('\n');
+	rijn_decrypt(&sched, plaintext, ciphertext);
+	hex_dump(plaintext, 16, stdout);
+	putchar('\n');
+	return 0;
+}
+
+#endif
+
+
+static int log_table[256] = {
+  0,   0,  25,   1,  50,   2,  26, 198,  75, 199,  27, 104,  51, 238, 223,   3,
+100,   4, 224,  14,  52, 141, 129, 239,  76, 113,   8, 200, 248, 105,  28, 193,
+125, 194,  29, 181, 249, 185,  39, 106,  77, 228, 166, 114, 154, 201,   9, 120,
+101,  47, 138,   5,  33,  15, 225,  36,  18, 240, 130,  69,  53, 147, 218, 142,
+150, 143, 219, 189,  54, 208, 206, 148,  19,  92, 210, 241,  64,  70, 131,  56,
+102, 221, 253,  48, 191,   6, 139,  98, 179,  37, 226, 152,  34, 136, 145,  16,
+126, 110,  72, 195, 163, 182,  30,  66,  58, 107,  40,  84, 250, 133,  61, 186,
+ 43, 121,  10,  21, 155, 159,  94, 202,  78, 212, 172, 229, 243, 115, 167,  87,
+175,  88, 168,  80, 244, 234, 214, 116,  79, 174, 233, 213, 231, 230, 173, 232,
+ 44, 215, 117, 122, 235,  22,  11, 245,  89, 203,  95, 176, 156, 169,  81, 160,
+127,  12, 246, 111,  23, 196,  73, 236, 216,  67,  31,  45, 164, 118, 123, 183,
+204, 187,  62,  90, 251,  96, 177, 134,  59,  82, 161, 108, 170,  85,  41, 157,
+151, 178, 135, 144,  97, 190, 220, 252, 188, 149, 207, 205,  55,  63,  91, 209,
+ 83,  57, 132,  60,  65, 162, 109,  71,  20,  42, 158,  93,  86, 242, 211, 171,
+ 68,  17, 146, 217,  35,  32,  46, 137, 180, 124, 184,  38, 119, 153, 227, 165,
+103,  74, 237, 222, 197,  49, 254,  24,  13,  99, 140, 128, 192, 247, 112,   7
+};
+
+static int antilog_table[256] = {
+  1,   3,   5,  15,  17,  51,  85, 255,  26,  46, 114, 150, 161, 248,  19,  53, 
+ 95, 225,  56,  72, 216, 115, 149, 164, 247,   2,   6,  10,  30,  34, 102, 170, 
+229,  52,  92, 228,  55,  89, 235,  38, 106, 190, 217, 112, 144, 171, 230,  49, 
+ 83, 245,   4,  12,  20,  60,  68, 204,  79, 209, 104, 184, 211, 110, 178, 205, 
+ 76, 212, 103, 169, 224,  59,  77, 215,  98, 166, 241,   8,  24,  40, 120, 136, 
+131, 158, 185, 208, 107, 189, 220, 127, 129, 152, 179, 206,  73, 219, 118, 154, 
+181, 196,  87, 249,  16,  48,  80, 240,  11,  29,  39, 105, 187, 214,  97, 163, 
+254,  25,  43, 125, 135, 146, 173, 236,  47, 113, 147, 174, 233,  32,  96, 160, 
+251,  22,  58,  78, 210, 109, 183, 194,  93, 231,  50,  86, 250,  21,  63,  65, 
+195,  94, 226,  61,  71, 201,  64, 192,  91, 237,  44, 116, 156, 191, 218, 117, 
+159, 186, 213, 100, 172, 239,  42, 126, 130, 157, 188, 223, 122, 142, 137, 128, 
+155, 182, 193,  88, 232,  35, 101, 175, 234,  37, 111, 177, 200,  67, 197,  84, 
+252,  31,  33,  99, 165, 244,   7,   9,  27,  45, 119, 153, 176, 203,  70, 202, 
+ 69, 207,  74, 222, 121, 139, 134, 145, 168, 227,  62,  66, 198,  81, 243,  14, 
+ 18,  54,  90, 238,  41, 123, 141, 140, 143, 138, 133, 148, 167, 242,  13,  23, 
+ 57,  75, 221, 124, 132, 151, 162, 253,  28,  36, 108, 180, 199,  82, 246,   1, 
+}; 
+
+static int s_box[256] = {
+ 99, 124, 119, 123, 242, 107, 111, 197,  48,   1, 103,  43, 254, 215, 171, 118,
+202, 130, 201, 125, 250,  89,  71, 240, 173, 212, 162, 175, 156, 164, 114, 192,
+183, 253, 147,  38,  54,  63, 247, 204,  52, 165, 229, 241, 113, 216,  49,  21,
+  4, 199,  35, 195,  24, 150,   5, 154,   7,  18, 128, 226, 235,  39, 178, 117,
+  9, 131,  44,  26,  27, 110,  90, 160,  82,  59, 214, 179,  41, 227,  47, 132,
+ 83, 209,   0, 237,  32, 252, 177,  91, 106, 203, 190,  57,  74,  76,  88, 207,
+208, 239, 170, 251,  67,  77,  51, 133,  69, 249,   2, 127,  80,  60, 159, 168,
+ 81, 163,  64, 143, 146, 157,  56, 245, 188, 182, 218,  33,  16, 255, 243, 210,
+205,  12,  19, 236,  95, 151,  68,  23, 196, 167, 126,  61, 100,  93,  25, 115,
+ 96, 129,  79, 220,  34,  42, 144, 136,  70, 238, 184,  20, 222,  94,  11, 219,
+224,  50,  58,  10,  73,   6,  36,  92, 194, 211, 172,  98, 145, 149, 228, 121,
+231, 200,  55, 109, 141, 213,  78, 169, 108,  86, 244, 234, 101, 122, 174,   8,
+186, 120,  37,  46,  28, 166, 180, 198, 232, 221, 116,  31,  75, 189, 139, 138,
+112,  62, 181, 102,  72,   3, 246,  14,  97,  53,  87, 185, 134, 193,  29, 158,
+225, 248, 152,  17, 105, 217, 142, 148, 155,  30, 135, 233, 206,  85,  40, 223,
+140, 161, 137,  13, 191, 230,  66, 104,  65, 153,  45,  15, 176,  84, 187,  22,
+};
+
+static int s_box_inverse[256] = {
+ 82,   9, 106, 213,  48,  54, 165,  56, 191,  64, 163, 158, 129, 243, 215, 251,
+124, 227,  57, 130, 155,  47, 255, 135,  52, 142,  67,  68, 196, 222, 233, 203,
+ 84, 123, 148,  50, 166, 194,  35,  61, 238,  76, 149,  11,  66, 250, 195,  78,
+  8,  46, 161, 102,  40, 217,  36, 178, 118,  91, 162,  73, 109, 139, 209,  37,
+114, 248, 246, 100, 134, 104, 152,  22, 212, 164,  92, 204,  93, 101, 182, 146,
+108, 112,  72,  80, 253, 237, 185, 218,  94,  21,  70,  87, 167, 141, 157, 132,
+144, 216, 171,   0, 140, 188, 211,  10, 247, 228,  88,   5, 184, 179,  69,   6,
+208,  44,  30, 143, 202,  63,  15,   2, 193, 175, 189,   3,   1,  19, 138, 107,
+ 58, 145,  17,  65,  79, 103, 220, 234, 151, 242, 207, 206, 240, 180, 230, 115,
+150, 172, 116,  34, 231, 173,  53, 133, 226, 249,  55, 232,  28, 117, 223, 110,
+ 71, 241,  26, 113,  29,  41, 197, 137, 111, 183,  98,  14, 170,  24, 190,  27,
+252,  86,  62,  75, 198, 210, 121,  32, 154, 219, 192, 254, 120, 205,  90, 244,
+ 31, 221, 168,  51, 136,   7, 199,  49, 177,  18,  16,  89,  39, 128, 236,  95,
+ 96,  81, 127, 169,  25, 181,  74,  13,  45, 229, 122, 159, 147, 201, 156, 239,
+160, 224,  59,  77, 174,  42, 245, 176, 200, 235, 187,  60, 131,  83, 153,  97,
+ 23,  43,   4, 126, 186, 119, 214,  38, 225, 105,  20,  99,  85,  33,  12, 125,
+};
+
+static int rcon[30] = {
+	0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8,
+	0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4,
+	0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91
+};
diff --git a/rijndael.h b/rijndael.h
new file mode 100644
index 0000000..a1694d2
--- /dev/null
+++ b/rijndael.h
@@ -0,0 +1,74 @@
+/*
+ * Highly portable ANSI C implementation of Rijndael cipher.
+ * Written by Kaz Kylheku.
+ */
+
+#ifndef RIJNDAEL_H
+#define RIJNDAEL_H
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define RIJN_MAX_ROUNDS 14
+
+/*
+ * Constants representing choice of Rijndael key or block size,
+ * either of which can be 128 bits, 192 bits or 256 bits.
+ */
+
+typedef enum {
+	rijn_128 = 4, 	/* number of rows */
+	rijn_192 = 6,
+	rijn_256 = 8
+} rijn_size_t;
+
+/*
+ * Rijndael parameters.
+ */
+
+typedef struct {
+	rijn_size_t rijn_blockrows;
+	rijn_size_t rijn_keyrows;
+} rijn_param_t;
+
+#define RIJN_PARAM_DEFAULT_INITIALIZER { rijn_128, rijn_256 }
+#define RIJN_PARAM_INITIALIZER(BLOCKSZ, KEYSZ) { (BLOCKSZ), (KEYSZ) }
+
+void rijn_param_init(rijn_param_t *, rijn_size_t blocksz, rijn_size_t keysz);
+
+/*
+ * Rijndael keys are 128, 192 or 256 bits wide.  There are up to
+ * RIJN_MAX_ROUNDS + 1 round keys needed, so the schedule is that big.
+ */
+
+typedef unsigned char rijn_unit_t[4];
+typedef rijn_unit_t rijn_key_t[8];
+typedef rijn_unit_t rijn_block_t[8];
+typedef unsigned char rijn_flatblock_t[sizeof (rijn_block_t)];
+
+typedef struct {
+	rijn_param_t rijn_param;
+	int rijn_nrounds;
+	rijn_block_t rijn_roundkey[RIJN_MAX_ROUNDS];
+} rijn_keysched_t;
+
+void rijn_sched_key(rijn_keysched_t *, rijn_key_t *, const rijn_param_t *);
+void rijn_encrypt(rijn_keysched_t *, unsigned char *, const unsigned char *);
+void rijn_decrypt(rijn_keysched_t *, unsigned char *, const unsigned char *);
+void rijn_cbc_encrypt(rijn_keysched_t *, unsigned char *iv, unsigned char *out, 
+		const unsigned char *in, size_t nblocks);
+void rijn_cbc_decrypt(rijn_keysched_t *, unsigned char *iv, unsigned char *out,
+		const unsigned char *in, size_t nblocks);
+void rijn_cfb_encrypt(rijn_keysched_t *, unsigned char *iv, unsigned char *out,
+		const unsigned char *pt, size_t nbytes);
+void rijn_cfb_decrypt(rijn_keysched_t *, unsigned char *iv, unsigned char *out,
+		const unsigned char *in, size_t nbytes);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif