From: Daniele Alessandrelli <daniele.alessandrelli@xxxxxxxxx>
Export the following additional ECC helper functions:
- ecc_alloc_point()
- ecc_free_point()
- vli_num_bits()
- ecc_point_is_zero()
- ecc_swap_digits()
This is done to allow future KPP device drivers to re-use existing code,
thus simplifying their implementation.
Functions are exported using EXPORT_SYMBOL() (instead of
EXPORT_SYMBOL_GPL()) to be consistent with the functions already
exported by crypto/ecc.c.
Exported functions are documented in crypto/ecc.h.
Signed-off-by: Daniele Alessandrelli <daniele.alessandrelli@xxxxxxxxx>
---
crypto/ecc.c | 16 ++++++++-----
include/crypto/internal/ecc.h | 44 +++++++++++++++++++++++++++++++++++
2 files changed, 54 insertions(+), 6 deletions(-)
diff --git a/crypto/ecc.c b/crypto/ecc.c
index 9aa801315a32..e8176db071d8 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -70,7 +70,7 @@ static void ecc_free_digits_space(u64 *space)
kfree_sensitive(space);
}
-static struct ecc_point *ecc_alloc_point(unsigned int ndigits)
+struct ecc_point *ecc_alloc_point(unsigned int ndigits)
{
struct ecc_point *p = kmalloc(sizeof(*p), GFP_KERNEL);
@@ -95,8 +95,9 @@ static struct ecc_point *ecc_alloc_point(unsigned int ndigits)
kfree(p);
return NULL;
}
+EXPORT_SYMBOL(ecc_alloc_point);
-static void ecc_free_point(struct ecc_point *p)
+void ecc_free_point(struct ecc_point *p)
{
if (!p)
return;
@@ -105,6 +106,7 @@ static void ecc_free_point(struct ecc_point *p)
kfree_sensitive(p->y);
kfree_sensitive(p);
}
+EXPORT_SYMBOL(ecc_free_point);
static void vli_clear(u64 *vli, unsigned int ndigits)
{
@@ -154,7 +156,7 @@ static unsigned int vli_num_digits(const u64 *vli, unsigned int ndigits)
}
/* Counts the number of bits required for vli. */
-static unsigned int vli_num_bits(const u64 *vli, unsigned int ndigits)
+unsigned int vli_num_bits(const u64 *vli, unsigned int ndigits)
{
unsigned int i, num_digits;
u64 digit;
@@ -169,6 +171,7 @@ static unsigned int vli_num_bits(const u64 *vli, unsigned int ndigits)
return ((num_digits - 1) * 64 + i);
}
+EXPORT_SYMBOL(vli_num_bits);
/* Set dest from unaligned bit string src. */
void vli_from_be64(u64 *dest, const void *src, unsigned int ndigits)
@@ -933,11 +936,12 @@ EXPORT_SYMBOL(vli_mod_inv);
/* ------ Point operations ------ */
/* Returns true if p_point is the point at infinity, false otherwise. */
-static bool ecc_point_is_zero(const struct ecc_point *point)
+bool ecc_point_is_zero(const struct ecc_point *point)
{
return (vli_is_zero(point->x, point->ndigits) &&
vli_is_zero(point->y, point->ndigits));
}
+EXPORT_SYMBOL(ecc_point_is_zero);
/* Point multiplication algorithm using Montgomery's ladder with co-Z
* coordinates. From https://eprint.iacr.org/2011/338.pdf
@@ -1281,8 +1285,7 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
}
EXPORT_SYMBOL(ecc_point_mult_shamir);
-static inline void ecc_swap_digits(const u64 *in, u64 *out,
- unsigned int ndigits)
+void ecc_swap_digits(const u64 *in, u64 *out, unsigned int ndigits)
{
const __be64 *src = (__force __be64 *)in;
int i;
@@ -1290,6 +1293,7 @@ static inline void ecc_swap_digits(const u64 *in, u64 *out,
for (i = 0; i < ndigits; i++)
out[i] = be64_to_cpu(src[ndigits - 1 - i]);
}
+EXPORT_SYMBOL(ecc_swap_digits);
static int __ecc_is_key_valid(const struct ecc_curve *curve,
const u64 *private_key, unsigned int ndigits)
diff --git a/include/crypto/internal/ecc.h b/include/crypto/internal/ecc.h
index d4e546b9ad79..2f6ac78b64f3 100644
--- a/include/crypto/internal/ecc.h
+++ b/include/crypto/internal/ecc.h
@@ -239,6 +239,41 @@ void vli_mod_inv(u64 *result, const u64 *input, const u64 *mod,
void vli_mod_mult_slow(u64 *result, const u64 *left, const u64 *right,
const u64 *mod, unsigned int ndigits);
+/**
+ * vli_num_bits() - Counts the number of bits required for vli.
+ *
+ * @vli: vli to check.
+ * @ndigits: Length of the @vli
+ *
+ * Return: The number of bits required to represent @vli.
+ */
+unsigned int vli_num_bits(const u64 *vli, unsigned int ndigits);
+
+/**
+ * ecc_aloc_point() - Allocate ECC point.
+ *
+ * @ndigits: Length of vlis in u64 qwords.
+ *
+ * Return: Pointer to the allocated point or NULL if allocation failed.
+ */
+struct ecc_point *ecc_alloc_point(unsigned int ndigits);
+
+/**
+ * ecc_free_point() - Free ECC point.
+ *
+ * @p: The point to free.
+ */
+void ecc_free_point(struct ecc_point *p);
+
+/**
+ * ecc_point_is_zero() - Check if point is zero.
+ *
+ * @p: Point to check for zero.
+ *
+ * Return: true if point is the point at infinity, false otherwise.
+ */
+bool ecc_point_is_zero(const struct ecc_point *point);
+
/**
* ecc_point_mult_shamir() - Add two points multiplied by scalars
*
@@ -256,4 +291,13 @@ void ecc_point_mult_shamir(const struct ecc_point *result,
const u64 *x, const struct ecc_point *p,
const u64 *y, const struct ecc_point *q,
const struct ecc_curve *curve);
+
+/**
+ * ecc_swap_digits() - Swap digits in vli.
+ *
+ * @in: The input vli (whose digits will be swapped).
+ * @out: The output vli (where swapped digits will be saved).
+ * @ndigits: Length of vli to be swapped.
+ */
+void ecc_swap_digits(const u64 *in, u64 *out, unsigned int ndigits);
#endif
--
2.26.2
