diff options
Diffstat (limited to 'src/field.h')
-rw-r--r-- | src/field.h | 62 |
1 files changed, 32 insertions, 30 deletions
diff --git a/src/field.h b/src/field.h index 41b280892d..2d52af5e36 100644 --- a/src/field.h +++ b/src/field.h @@ -10,7 +10,7 @@ /** Field element module. * * Field elements can be represented in several ways, but code accessing - * it (and implementations) need to take certain properaties into account: + * it (and implementations) need to take certain properties into account: * - Each field element can be normalized or not. * - Each field element has a magnitude, which represents how far away * its representation is away from normalization. Normalized elements @@ -31,89 +31,91 @@ #endif /** Normalize a field element. */ -static void secp256k1_fe_normalize(secp256k1_fe_t *r); +static void secp256k1_fe_normalize(secp256k1_fe *r); /** Weakly normalize a field element: reduce it magnitude to 1, but don't fully normalize. */ -static void secp256k1_fe_normalize_weak(secp256k1_fe_t *r); +static void secp256k1_fe_normalize_weak(secp256k1_fe *r); /** Normalize a field element, without constant-time guarantee. */ -static void secp256k1_fe_normalize_var(secp256k1_fe_t *r); +static void secp256k1_fe_normalize_var(secp256k1_fe *r); /** Verify whether a field element represents zero i.e. would normalize to a zero value. The field * implementation may optionally normalize the input, but this should not be relied upon. */ -static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r); +static int secp256k1_fe_normalizes_to_zero(secp256k1_fe *r); /** Verify whether a field element represents zero i.e. would normalize to a zero value. The field * implementation may optionally normalize the input, but this should not be relied upon. */ -static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r); +static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe *r); /** Set a field element equal to a small integer. Resulting field element is normalized. */ -static void secp256k1_fe_set_int(secp256k1_fe_t *r, int a); +static void secp256k1_fe_set_int(secp256k1_fe *r, int a); /** Verify whether a field element is zero. Requires the input to be normalized. */ -static int secp256k1_fe_is_zero(const secp256k1_fe_t *a); +static int secp256k1_fe_is_zero(const secp256k1_fe *a); /** Check the "oddness" of a field element. Requires the input to be normalized. */ -static int secp256k1_fe_is_odd(const secp256k1_fe_t *a); +static int secp256k1_fe_is_odd(const secp256k1_fe *a); /** Compare two field elements. Requires magnitude-1 inputs. */ -static int secp256k1_fe_equal_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b); +static int secp256k1_fe_equal_var(const secp256k1_fe *a, const secp256k1_fe *b); /** Compare two field elements. Requires both inputs to be normalized */ -static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b); +static int secp256k1_fe_cmp_var(const secp256k1_fe *a, const secp256k1_fe *b); -/** Set a field element equal to 32-byte big endian value. If succesful, the resulting field element is normalized. */ -static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a); +/** Set a field element equal to 32-byte big endian value. If successful, the resulting field element is normalized. */ +static int secp256k1_fe_set_b32(secp256k1_fe *r, const unsigned char *a); /** Convert a field element to a 32-byte big endian value. Requires the input to be normalized */ -static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe_t *a); +static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe *a); /** Set a field element equal to the additive inverse of another. Takes a maximum magnitude of the input * as an argument. The magnitude of the output is one higher. */ -static void secp256k1_fe_negate(secp256k1_fe_t *r, const secp256k1_fe_t *a, int m); +static void secp256k1_fe_negate(secp256k1_fe *r, const secp256k1_fe *a, int m); /** Multiplies the passed field element with a small integer constant. Multiplies the magnitude by that * small integer. */ -static void secp256k1_fe_mul_int(secp256k1_fe_t *r, int a); +static void secp256k1_fe_mul_int(secp256k1_fe *r, int a); /** Adds a field element to another. The result has the sum of the inputs' magnitudes as magnitude. */ -static void secp256k1_fe_add(secp256k1_fe_t *r, const secp256k1_fe_t *a); +static void secp256k1_fe_add(secp256k1_fe *r, const secp256k1_fe *a); /** Sets a field element to be the product of two others. Requires the inputs' magnitudes to be at most 8. * The output magnitude is 1 (but not guaranteed to be normalized). */ -static void secp256k1_fe_mul(secp256k1_fe_t *r, const secp256k1_fe_t *a, const secp256k1_fe_t * SECP256K1_RESTRICT b); +static void secp256k1_fe_mul(secp256k1_fe *r, const secp256k1_fe *a, const secp256k1_fe * SECP256K1_RESTRICT b); /** Sets a field element to be the square of another. Requires the input's magnitude to be at most 8. * The output magnitude is 1 (but not guaranteed to be normalized). */ -static void secp256k1_fe_sqr(secp256k1_fe_t *r, const secp256k1_fe_t *a); +static void secp256k1_fe_sqr(secp256k1_fe *r, const secp256k1_fe *a); -/** Sets a field element to be the (modular) square root (if any exist) of another. Requires the - * input's magnitude to be at most 8. The output magnitude is 1 (but not guaranteed to be - * normalized). Return value indicates whether a square root was found. */ -static int secp256k1_fe_sqrt_var(secp256k1_fe_t *r, const secp256k1_fe_t *a); +/** If a has a square root, it is computed in r and 1 is returned. If a does not + * have a square root, the root of its negation is computed and 0 is returned. + * The input's magnitude can be at most 8. The output magnitude is 1 (but not + * guaranteed to be normalized). The result in r will always be a square + * itself. */ +static int secp256k1_fe_sqrt_var(secp256k1_fe *r, const secp256k1_fe *a); /** Sets a field element to be the (modular) inverse of another. Requires the input's magnitude to be * at most 8. The output magnitude is 1 (but not guaranteed to be normalized). */ -static void secp256k1_fe_inv(secp256k1_fe_t *r, const secp256k1_fe_t *a); +static void secp256k1_fe_inv(secp256k1_fe *r, const secp256k1_fe *a); /** Potentially faster version of secp256k1_fe_inv, without constant-time guarantee. */ -static void secp256k1_fe_inv_var(secp256k1_fe_t *r, const secp256k1_fe_t *a); +static void secp256k1_fe_inv_var(secp256k1_fe *r, const secp256k1_fe *a); /** Calculate the (modular) inverses of a batch of field elements. Requires the inputs' magnitudes to be * at most 8. The output magnitudes are 1 (but not guaranteed to be normalized). The inputs and * outputs must not overlap in memory. */ -static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe_t *r, const secp256k1_fe_t *a); +static void secp256k1_fe_inv_all_var(size_t len, secp256k1_fe *r, const secp256k1_fe *a); /** Convert a field element to the storage type. */ -static void secp256k1_fe_to_storage(secp256k1_fe_storage_t *r, const secp256k1_fe_t*); +static void secp256k1_fe_to_storage(secp256k1_fe_storage *r, const secp256k1_fe *a); /** Convert a field element back from the storage type. */ -static void secp256k1_fe_from_storage(secp256k1_fe_t *r, const secp256k1_fe_storage_t*); +static void secp256k1_fe_from_storage(secp256k1_fe *r, const secp256k1_fe_storage *a); /** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. */ -static void secp256k1_fe_storage_cmov(secp256k1_fe_storage_t *r, const secp256k1_fe_storage_t *a, int flag); +static void secp256k1_fe_storage_cmov(secp256k1_fe_storage *r, const secp256k1_fe_storage *a, int flag); /** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. */ -static void secp256k1_fe_cmov(secp256k1_fe_t *r, const secp256k1_fe_t *a, int flag); +static void secp256k1_fe_cmov(secp256k1_fe *r, const secp256k1_fe *a, int flag); #endif |