Merge branch 'master' of ssh://gitlab.hasufell.de:22022/pcq/quantumcrypto

src/Makefile

@@ -4,7 +4,7 @@ PKG_CONFIG ?= pkg-config
 
 # flags
 CFLAGS ?= -march=native -O2 -pipe
-CFLAGS += -std=c99 -pedantic -Wall -Wextra -Werror -Wno-unused-variable
+CFLAGS += -std=c99 -pedantic -Wall -Wextra -Werror -Wno-unused-variable -Wno-unused-parameter
 ifeq ($(shell $(CC) -v 2>&1 | grep 'gcc version' &>/dev/null && echo 1),1)
 CFLAGS += -Wno-unused-but-set-variable
 endif
@@ -80,7 +80,7 @@ libpqc.so: libpqc.a $(PQC_HEADERS) $(LIBTOMMATH) $(LIBTOMPOLY)
 
 main: main.o libpqc.a $(LIBTOMMATH) $(LIBTOMPOLY)
 	$(CC) $(CFLAGS) -o $@ $(LDFLAGS) \
-		main.o libpqc.a $(LIBTOMMATH) $(LIBTOMPOLY) $(LIBS)
+		main.o $(LIBTOMPOLY) libpqc.a $(LIBTOMPOLY) $(LIBTOMMATH) $(LIBS)
 
 install:
 	$(INSTALL_DIR) "$(DESTDIR)$(INSTALL_BINDIR)"

src/context.h

@@ -32,15 +32,15 @@ typedef struct {
 	 * maximal degree N - 1 for
 	 * all polynomials
 	 */
-	int N;
+	unsigned int N;
 	/**
 	 * large modulus
 	 */
-	int q;
+	unsigned int q;
 	/**
 	 * small modulus
 	 */
-	int p;
+	unsigned int p;
 } ntru_context;
 
 #endif /* NTRU_CONTEXT_H */

src/poly.c

@@ -19,15 +19,26 @@
  * MA  02110-1301  USA
  */
 
+#include "context.h"
 #include "err.h"
+#include "poly.h"
 
+#include <stdbool.h>
 #include <stdio.h>
 #include <tompoly.h>
 #include <tommath.h>
+#include <stdbool.h>
+
+
+/*
+ * static declarations
+ */
+static unsigned int get_degree(pb_poly const * const poly);
+
 
 /**
  * Initialize a mp_int and check if this was successful, the
- * caller must free new_int.
+ * caller must free new_int with mp_clear().
  *
  * @param new_int a pointer to the mp_int you want to initialize
  */
@@ -42,7 +53,8 @@ void init_integer(mp_int *new_int)
 
 /**
  * Initialize a Polynom with a pb_poly and a mp_int as characteristic.
- * Checks if everything went fine. The caller must free new_poly.
+ * Checks if everything went fine. The caller must free new_poly
+ * with pb_clear().
  *
  * @param new_poly the pb_poly you want to initialize
  * @param chara the characteristic
@@ -57,15 +69,15 @@ void init_polynom(pb_poly *new_poly, mp_int *chara)
 }
 
 /**
- * Initialize a Polynom with a pb_poly adn a mp_int as characteristic
+ * Initialize a Polynom with a pb_poly and an mp_int as characteristic
  * with size. Checks if everything went fine. The caller must free
- * new_poly.
+ * new_poly with pb_clear().
  *
  * @param new_poly the pb_poly you want to initialize
  * @param chara the characteristic
  * @param size the size of the polynomial
  */
-void init_polynom_size(pb_poly *new_poly, mp_int *chara, int size)
+void init_polynom_size(pb_poly *new_poly, mp_int *chara, size_t size)
 {
 	int result;
 	if ((result = pb_init_size(new_poly, chara, size)) != MP_OKAY) {
@@ -74,6 +86,75 @@ void init_polynom_size(pb_poly *new_poly, mp_int *chara, int size)
 	}
 }
 
+/**
+ * Initializes and builds a polynomial with the
+ * coefficient values of c[] of size len within NTRU
+ * context ctx and returns a newly allocated polynomial
+ * pointer which is not clamped.
+ *
+ * If you want to fill a polyonmial of length 11 with zeros,
+ * call build_polynom(NULL, 11, ctx).
+ *
+ * @param c array of polynomial coefficients, can be NULL
+ * @param len size of the coefficient array, can be 0
+ * @param ctx NTRU context
+ * @return newly allocated polynomial pointer, must be freed
+ * with delete_polynom()
+ */
+pb_poly *build_polynom(int const * const c,
+		const size_t len,
+		ntru_context *ctx)
+{
+	pb_poly *new_poly;
+	mp_int chara;
+
+	new_poly = malloc(sizeof(*new_poly));
+	init_integer(&chara);
+	init_polynom_size(new_poly, &chara, len);
+	mp_clear(&chara);
+
+	/* fill the polynom if c is not NULL */
+	if (c) {
+		for (unsigned int i = 0; i < len; i++) {
+			bool sign = false;
+			unsigned long unsigned_c;
+
+			if (c[i] < 0) {
+				unsigned_c = 0 - c[i];
+				sign = true;
+			} else {
+				unsigned_c = c[i];
+			}
+
+			mp_set_int(&(new_poly->terms[i]), unsigned_c);
+
+			if (sign == true)
+				mp_neg(&(new_poly->terms[i]), &(new_poly->terms[i]));
+		}
+	} else { /* fill with zeros */
+		for (unsigned int i = 0; i < len; i++)
+			mp_set(&(new_poly->terms[i]), 0);
+	}
+
+	new_poly->used = len;
+
+	return new_poly;
+}
+
+/**
+ * Sets all the polynomial coefficients to +0.
+ *
+ * @param poly the polynomial
+ * @param len the length of the polynomial
+ */
+void erase_polynom(pb_poly *poly, size_t len)
+{
+	for (unsigned int i = 0; i < len ; i++) {
+		mp_set(&(poly->terms[i]), 0);
+		mp_abs(&(poly->terms[i]), &(poly->terms[i]));
+	}
+}
+
 /**
  * This deletes the internal structure of a polynomial,
  * and frees the pointer. Don't call this on stack variables,
@@ -88,6 +169,200 @@ void delete_polynom(pb_poly *poly)
 	free(poly);
 }
 
+/**
+ * Starmultiplication, as follows:
+ * c = a * b mod (x^N − 1)
+ *
+ * @param a polynom to multiply (can be the same as c)
+ * @param b polynom to multiply
+ * @param c polynom [out]
+ * @param ctx NTRU context
+ * @param modulus whether we use p or q
+ */
+void pb_starmultiply(pb_poly *a,
+		pb_poly *b,
+		pb_poly *c,
+		ntru_context *ctx,
+		unsigned int modulus)
+{
+	pb_poly *a_tmp;
+	mp_int mp_modulus;
+
+	init_integer(&mp_modulus);
+	mp_set_int(&mp_modulus, (unsigned long)(modulus));
+
+	/* avoid side effects */
+	a_tmp = build_polynom(NULL, ctx->N, ctx);
+	PB_COPY(a, a_tmp);
+	erase_polynom(c, ctx->N);
+
+	for (int k = ctx->N - 1; k >= 0; k--) {
+		int j;
+		j = k + 1;
+
+		for (int i = ctx->N - 1; i >= 0; i--) {
+			if (j == (int)(ctx->N))
+				j = 0;
+			if (mp_cmp_d(&(a_tmp->terms[i]), 0) != MP_EQ &&
+					mp_cmp_d(&(b->terms[j]), 0) != MP_EQ) {
+				mp_int mp_tmp;
+
+				init_integer(&mp_tmp);
+
+				MP_MUL(&(a_tmp->terms[i]), &(b->terms[j]), &mp_tmp);
+				MP_ADD(&(c->terms[k]), &mp_tmp, &(c->terms[k]));
+				MP_DIV(&(c->terms[k]), &mp_modulus, NULL, &(c->terms[k]));
+
+				mp_clear(&mp_tmp);
+			}
+			j++;
+		}
+	}
+	mp_clear(&mp_modulus);
+	delete_polynom(a_tmp);
+}
+
+/**
+ * c = a XOR b
+ *
+ * @param a polynom (is allowed to be the same as param c)
+ * @param b polynom
+ * @param c polynom [out]
+ * @param len max size of the polynoms, make sure all are
+ * properly allocated
+ */
+void pb_xor(pb_poly *a,
+		pb_poly *b,
+		pb_poly *c,
+		const size_t len)
+{
+	for (unsigned int i = 0; i < len; i++)
+		MP_XOR(&(a->terms[i]), &(b->terms[i]), &(c->terms[i]));
+}
+
+/**
+ * Get the degree of the polynomial.
+ *
+ * @param poly the polynomial
+ * @return the degree
+ */
+static unsigned int get_degree(pb_poly const * const poly)
+{
+	unsigned int count = 0;
+
+	for (int i = 0; i < poly->alloc; i++)
+		if (mp_iszero(&(poly->terms[i])) == MP_NO)
+			count = i;
+
+	return count;
+}
+
+/**
+ * Invert the polynomial a modulo q.
+ *
+ * @param a polynomial to invert (is allowed to be the same as param Fq)
+ * @param Fq polynomial [out]
+ * @param ctx NTRU context
+ * @return true/false for success/failure
+ */
+bool pb_inverse_poly_q(pb_poly * const a,
+		pb_poly *Fq,
+		ntru_context *ctx)
+{
+	int k = 0,
+		j = 0,
+		v = 2;
+	pb_poly *a_tmp, *b, *c, *f, *g;
+
+	b = build_polynom(NULL, ctx->N + 1, ctx);
+	mp_set(&(b->terms[0]), 1);
+	c = build_polynom(NULL, ctx->N + 1, ctx);
+	f = build_polynom(NULL, ctx->N + 1, ctx);
+	PB_COPY(a, f);
+	g = build_polynom(NULL, ctx->N + 1, ctx);
+	mp_set(&(g->terms[0]), 1);
+	mp_neg(&(g->terms[0]), &(g->terms[0]));
+	mp_set(&(g->terms[ctx->N]), 1);
+	/* avoid side effects */
+	a_tmp = build_polynom(NULL, ctx->N, ctx);
+	PB_COPY(a, a_tmp);
+	erase_polynom(Fq, ctx->N);
+
+	while (1) {
+		while (mp_cmp_d(&(f->terms[0]), 0) == MP_EQ) {
+			for (unsigned int i = 1; i <= ctx->N; i++) {
+				MP_COPY(&(f->terms[i]), &(f->terms[i - 1]));
+				MP_COPY(&(c->terms[ctx->N - i]), &(c->terms[ctx->N + 1 - i]));
+			}
+			mp_set(&(f->terms[ctx->N]), 0);
+			mp_set(&(c->terms[0]), 0);
+			k++;
+		}
+
+		if (get_degree(f) == 0)
+			goto OUT_OF_LOOP;
+
+		if (get_degree(f) < get_degree(g)) {
+			pb_exch(f, g);
+			pb_exch(b, c);
+		}
+
+		pb_xor(f, g, f, ctx->N);
+		pb_xor(b, c, b, ctx->N);
+	}
+
+OUT_OF_LOOP:
+	k = k % ctx->N;
+
+	for (int i = ctx->N - 1; i >= 0; i--) {
+		j = i - k;
+		if (j < 0)
+			j = j + ctx->N;
+		MP_COPY(&(b->terms[i]), &(Fq->terms[j]));
+	}
+
+	while (v < (int)(ctx->q)) {
+		pb_poly *pb_tmp,
+				*pb_tmp2;
+		mp_int tmp_v;
+		pb_tmp = build_polynom(NULL, ctx->N, ctx);
+		v = v * 2;
+		init_integer(&tmp_v);
+		mp_set_int(&tmp_v, v);
+		pb_tmp2 = build_polynom(NULL, ctx->N, ctx);
+		mp_set_int(&(pb_tmp2->terms[0]), 2);
+
+		/* hope this does not blow up in our face */
+		pb_starmultiply(a_tmp, Fq, pb_tmp, ctx, v);
+		PB_SUB(pb_tmp2, pb_tmp, pb_tmp);
+		PB_MOD(pb_tmp, &tmp_v, pb_tmp, ctx->N);
+		pb_starmultiply(Fq, pb_tmp, Fq, ctx, v);
+
+		mp_clear(&tmp_v);
+		delete_polynom(pb_tmp);
+		delete_polynom(pb_tmp2);
+	}
+
+	for (int i = ctx->N - 1; i >= 0; i--)
+		if (mp_cmp_d(&(Fq->terms[i]), 0) == MP_LT) {
+			mp_int mp_tmp;
+			init_integer(&mp_tmp);
+			mp_set_int(&mp_tmp, ctx->q);
+			MP_ADD(&(Fq->terms[i]), &mp_tmp, &(Fq->terms[i]));
+			mp_clear(&mp_tmp);
+		}
+
+	delete_polynom(a_tmp);
+	delete_polynom(b);
+	delete_polynom(c);
+	delete_polynom(f);
+	delete_polynom(g);
+
+	/* TODO: check if the f * Fq = 1 (mod p) condition holds true */
+
+	return true;
+}
+
 /**
  * Print the polynomial in a human readable format to stdout.
  *

src/poly.h

@@ -23,18 +23,136 @@
 #ifndef NTRU_POLY_H
 #define NTRU_POLY_H
 
+#include "context.h"
+#include "err.h"
+
 #include <tompoly.h>
 #include <tommath.h>
+#include <stdbool.h>
 
+#define MP_MUL(...) \
+{ \
+	int result; \
+	if ((result = mp_mul(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error multiplying terms. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define MP_DIV(...) \
+{ \
+	int result; \
+	if ((result = mp_div(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error dividing terms. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define MP_ADD(...) \
+{ \
+	int result; \
+	if ((result = mp_add(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error adding terms. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define MP_SUB(...) \
+{ \
+	int result; \
+	if ((result = mp_sub(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error substracting terms. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define MP_MOD(...) \
+{ \
+	int result; \
+	if ((result = mp_mod(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error reducing term by modulo. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define MP_COPY(...) \
+{ \
+	int result; \
+	if ((result = mp_copy(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error copying terms. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define MP_XOR(...) \
+{ \
+	int result; \
+	if ((result = mp_xor(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error XORing terms. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define PB_MUL(...) \
+{ \
+	int result; \
+	if ((result = pb_mul(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error multiplying polynomials. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define PB_ADD(...) \
+{ \
+	int result; \
+	if ((result = pb_add(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error adding polynomials. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define PB_SUB(...) \
+{ \
+	int result; \
+	if ((result = pb_sub(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error substracting polynomials. %s", \
+				mp_error_to_string(result)); \
+}
+
+#define PB_MOD(poly_a, mp_int, poly_out, len) \
+{ \
+	for (unsigned int i = 0; i < len; i++) \
+		MP_DIV(&(poly_a->terms[i]), mp_int, NULL, &(poly_out->terms[i])); \
+}
+
+#define PB_COPY(...) \
+{ \
+	int result; \
+	if ((result = pb_copy(__VA_ARGS__)) != MP_OKAY) \
+			NTRU_ABORT("Error copying polynomial. %s", \
+				mp_error_to_string(result)); \
+}
 
 void init_integer(mp_int *new_int);
 
 void init_polynom(pb_poly *new_poly, mp_int *chara);
 
-void init_polynom_size(pb_poly *new_poly, mp_int *chara, int size);
+void init_polynom_size(pb_poly *new_poly, mp_int *chara, size_t size);
+
+pb_poly *build_polynom(int const * const c,
+		const size_t len,
+		ntru_context *ctx);
+
+void erase_polynom(pb_poly *poly, size_t len);
 
 void delete_polynom(pb_poly *new_poly);
 
+void pb_starmultiply(pb_poly *a,
+		pb_poly *b,
+		pb_poly *c,
+		ntru_context *ctx,
+		unsigned int modulus);
+
+void pb_xor(pb_poly *a,
+		pb_poly *b,
+		pb_poly *c,
+		const size_t len);
+
+bool pb_inverse_poly_q(pb_poly *a,
+		pb_poly *Fq,
+		ntru_context *ctx);
+
 void draw_polynom(pb_poly * const poly);
 
 #endif /* NTRU_POLY_H */

src/rand.c

@@ -36,7 +36,7 @@
 /*
  * static declarations
  */
-static mp_digit get_urnd_int_small(int *sign);
+static unsigned long get_urnd_int_small(int *sign);
 
 
 /**
@@ -46,7 +46,7 @@ static mp_digit get_urnd_int_small(int *sign);
  * @param sign stores the signness [out]
  * @return random small integer
  */
-static mp_digit get_urnd_int_small(int *sign)
+static unsigned long get_urnd_int_small(int *sign)
 {
 	int random_data;
 	mp_digit random_int;
@@ -86,11 +86,11 @@ pb_poly *ntru_get_urnd_poly_small(ntru_context *ctx)
 	init_polynom_size(poly, &chara, ctx->N);
 	mp_clear(&chara);
 
-	for (int i = 0; i < ctx->N; i++) {
+	for (unsigned int i = 0; i < ctx->N; i++) {
 		int sign;
-		int c = get_urnd_int_small(&sign);
+		unsigned long c = get_urnd_int_small(&sign);
 
-		mp_set(&(poly->terms[i]), (mp_digit)c);
+		mp_set_int(&(poly->terms[i]), c);
 
 		if (sign == 1)
 			poly->terms[i].sign = 1;