mirror of
https://github.com/neocturne/libuecc.git
synced 2025-03-04 09:03:31 +01:00
Lots of code documentation
This commit is contained in:
parent
9c832519c6
commit
9d875f0418
4 changed files with 202 additions and 19 deletions
12
Doxyfile.in
12
Doxyfile.in
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@ -114,7 +114,7 @@ FULL_PATH_NAMES = NO
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# If left blank the directory from which doxygen is run is used as the
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# path to strip.
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STRIP_FROM_PATH =
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STRIP_FROM_PATH = include
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# The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of
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# the path mentioned in the documentation of a class, which tells
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@ -137,7 +137,7 @@ SHORT_NAMES = NO
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# comments will behave just like regular Qt-style comments
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# (thus requiring an explicit @brief command for a brief description.)
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JAVADOC_AUTOBRIEF = NO
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JAVADOC_AUTOBRIEF = YES
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# If the QT_AUTOBRIEF tag is set to YES then Doxygen will
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# interpret the first line (until the first dot) of a Qt-style
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@ -270,7 +270,7 @@ SUBGROUPING = YES
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# be useful for C code in case the coding convention dictates that all compound
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# types are typedef'ed and only the typedef is referenced, never the tag name.
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TYPEDEF_HIDES_STRUCT = NO
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TYPEDEF_HIDES_STRUCT = YES
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# The SYMBOL_CACHE_SIZE determines the size of the internal cache use to
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# determine which symbols to keep in memory and which to flush to disk.
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@ -1199,13 +1199,13 @@ ENABLE_PREPROCESSING = YES
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# compilation will be performed. Macro expansion can be done in a controlled
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# way by setting EXPAND_ONLY_PREDEF to YES.
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MACRO_EXPANSION = NO
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MACRO_EXPANSION = YES
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# If the EXPAND_ONLY_PREDEF and MACRO_EXPANSION tags are both set to YES
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# then the macro expansion is limited to the macros specified with the
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# PREDEFINED and EXPAND_AS_DEFINED tags.
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EXPAND_ONLY_PREDEF = NO
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EXPAND_ONLY_PREDEF = YES
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# If the SEARCH_INCLUDES tag is set to YES (the default) the includes files
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# in the INCLUDE_PATH (see below) will be search if a #include is found.
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@ -1233,7 +1233,7 @@ INCLUDE_FILE_PATTERNS =
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# undefined via #undef or recursively expanded use the := operator
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# instead of the = operator.
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PREDEFINED =
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PREDEFINED = DEPRECATED=
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# If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then
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# this tag can be used to specify a list of macro names that should be expanded.
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@ -31,15 +31,28 @@
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#define DEPRECATED __attribute__((deprecated))
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#endif
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/**
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* A 256 bit integer
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*
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* All functions of libuecc treat \ref ecc_int256_t as unsigned little-endian.
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*/
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typedef union _ecc_int256 {
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/** Data bytes */
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unsigned char p[32];
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/* old name */
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/**
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* Old name of p
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* \deprecated Use \ref ecc_int256_t::p instead.
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*/
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unsigned char s[32] DEPRECATED;
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} ecc_int256_t;
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/* a point on the curve unpacked for efficient calculation */
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/**
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* A point on the curve unpacked for efficient calculation
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*
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* The internal representation of an unpacked point isn't unique, so for serialization
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* it should always be packed.
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*/
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typedef struct _ecc_25519_work {
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unsigned int X[32];
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unsigned int Y[32];
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@ -47,6 +60,10 @@ typedef struct _ecc_25519_work {
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unsigned int T[32];
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} ecc_25519_work_t;
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/**
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* \defgroup curve_ops Operations on points of the Elliptic Curve
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* @{
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*/
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void ecc_25519_load_xy(ecc_25519_work_t *out, const ecc_int256_t *x, const ecc_int256_t *y);
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void ecc_25519_store_xy(ecc_int256_t *x, ecc_int256_t *y, const ecc_25519_work_t *in);
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@ -55,12 +72,18 @@ void ecc_25519_load_packed(ecc_25519_work_t *out, const ecc_int256_t *in);
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void ecc_25519_store_packed(ecc_int256_t *out, const ecc_25519_work_t *in);
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int ecc_25519_is_identity(const ecc_25519_work_t *in);
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void ecc_25519_add(ecc_25519_work_t *out, const ecc_25519_work_t *in1, const ecc_25519_work_t *in2);
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void ecc_25519_double(ecc_25519_work_t *out, const ecc_25519_work_t *in);
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void ecc_25519_add(ecc_25519_work_t *out, const ecc_25519_work_t *in1, const ecc_25519_work_t *in2);
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void ecc_25519_scalarmult(ecc_25519_work_t *out, const ecc_int256_t *n, const ecc_25519_work_t *base);
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void ecc_25519_scalarmult_base(ecc_25519_work_t *out, const ecc_int256_t *n);
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/* operations on elements of the prime field F_q for q = 2^252 + 27742317777372353535851937790883648493 */
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/**@}*/
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/**
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* \defgroup gf_ops Prime field operations for the order of the base point of the Elliptic Curve
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* @{
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*/
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extern const ecc_int256_t ecc_25519_gf_order;
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int ecc_25519_gf_is_zero(const ecc_int256_t *in);
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@ -69,42 +92,99 @@ void ecc_25519_gf_sub(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int2
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void ecc_25519_gf_reduce(ecc_int256_t *out, const ecc_int256_t *in);
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void ecc_25519_gf_mult(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int256_t *in2);
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void ecc_25519_gf_recip(ecc_int256_t *out, const ecc_int256_t *in);
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void ecc_25519_gf_sanitize_secret(ecc_int256_t *out, const ecc_int256_t *in);
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/**@}*/
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/* declarations for the old names */
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/**
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* Old name of \ref ecc_int256_t
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* \deprecated Use \ref ecc_int256_t instead.
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*/
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typedef ecc_int256_t ecc_secret_key_256 DEPRECATED;
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/**
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* Old name of \ref ecc_int256_t
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* \deprecated Use \ref ecc_int256_t instead.
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*/
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typedef ecc_int256_t ecc_public_key_256 DEPRECATED;
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/**
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* Old name of \ref ecc_25519_work_t
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* \deprecated Use \ref ecc_25519_work_t instead.
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*/
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typedef ecc_25519_work_t ecc_25519_work DEPRECATED;
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/**
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* Loads a packed point into its unpacked representation
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*
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* \deprecated Use \ref ecc_25519_load_packed instead.
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*/
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DEPRECATED static inline void ecc_25519_load(ecc_25519_work_t *out, const ecc_int256_t *in) {
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ecc_25519_load_packed(out, in);
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}
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/**
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* Stores a point into its packed representation
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*
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* \deprecated Use \ref ecc_25519_store_packed instead.
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*/
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DEPRECATED static inline void ecc_25519_store(ecc_int256_t *out, const ecc_25519_work_t *in) {
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ecc_25519_store_packed(out, in);
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}
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/**
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* Checks if an integer is equal to zero (after reduction)
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*
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* \deprecated Use \ref ecc_25519_gf_is_zero instead.
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*/
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DEPRECATED static inline int ecc_25519_secret_is_zero(const ecc_int256_t *in) {
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return ecc_25519_gf_is_zero(in);
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}
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/**
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* Adds two integers as Galois field elements
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*
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* \deprecated Use \ref ecc_25519_gf_add instead.
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*/
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DEPRECATED static inline void ecc_25519_secret_add(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int256_t *in2) {
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ecc_25519_gf_add(out, in1, in2);
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}
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/**
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* Subtracts two integers as Galois field elements
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*
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* \deprecated Use \ref ecc_25519_gf_sub instead.
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*/
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DEPRECATED static inline void ecc_25519_secret_sub(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int256_t *in2) {
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ecc_25519_gf_sub(out, in1, in2);
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}
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/**
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* Reduces an integer to a unique representation in the range \f$ [0,q-1] \f$
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*
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* \deprecated Use \ref ecc_25519_gf_reduce instead.
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*/
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DEPRECATED static inline void ecc_25519_secret_reduce(ecc_int256_t *out, const ecc_int256_t *in) {
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ecc_25519_gf_reduce(out, in);
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}
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/**
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* Multiplies to integers as Galois field elements
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*
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* \deprecated Use \ref ecc_25519_gf_mult instead.
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*/
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DEPRECATED static inline void ecc_25519_secret_mult(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int256_t *in2) {
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ecc_25519_gf_mult(out, in1, in2);
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}
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/**
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* Ensures some properties of a Galois field element to make it fit for use as a secret key
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*
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* \deprecated Use \ref ecc_25519_gf_sanitize_secret instead.
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*/
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DEPRECATED static inline void ecc_25519_secret_sanitize(ecc_int256_t *out, const ecc_int256_t *in) {
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ecc_25519_gf_sanitize_secret(out, in);
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}
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@ -40,6 +40,7 @@
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#include <libuecc/ecc.h>
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/** Adds two unpacked integers (modulo p) */
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static void add(unsigned int out[32], const unsigned int a[32], const unsigned int b[32]) {
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unsigned int j;
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unsigned int u;
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@ -48,6 +49,7 @@ static void add(unsigned int out[32], const unsigned int a[32], const unsigned i
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u += a[31] + b[31]; out[31] = u;
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}
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/** Subtracts two unpacked integers (modulo p) */
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static void sub(unsigned int out[32], const unsigned int a[32], const unsigned int b[32]) {
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unsigned int j;
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unsigned int u;
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@ -61,6 +63,7 @@ static void sub(unsigned int out[32], const unsigned int a[32], const unsigned i
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out[31] = u;
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}
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/** Performs carry and reduce on an unpacked integer */
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static void squeeze(unsigned int a[32]) {
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unsigned int j;
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unsigned int u;
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@ -72,6 +75,11 @@ static void squeeze(unsigned int a[32]) {
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u += a[31]; a[31] = u;
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}
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/**
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* Ensures that the output of a previous \ref squeeze is fully reduced
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*
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* After a \ref freeze, only the lower byte of each integer part holds a meaningful value
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*/
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static void freeze(unsigned int a[32]) {
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static const unsigned int minusp[32] = {
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19, 0, 0, 0, 0, 0, 0, 0,
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@ -90,6 +98,7 @@ static void freeze(unsigned int a[32]) {
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for (j = 0; j < 32; j++) a[j] ^= negative & (aorig[j] ^ a[j]);
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}
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/** Multiplies two unpacked integers (modulo p) */
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static void mult(unsigned int out[32], const unsigned int a[32], const unsigned int b[32]) {
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unsigned int i;
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unsigned int j;
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@ -104,6 +113,7 @@ static void mult(unsigned int out[32], const unsigned int a[32], const unsigned
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squeeze(out);
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}
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/** Multiplies an unpacked integer with a small integer (modulo p) */
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static void mult_int(unsigned int out[32], const unsigned int n, const unsigned int a[32]) {
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unsigned int j;
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unsigned int u;
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@ -116,6 +126,7 @@ static void mult_int(unsigned int out[32], const unsigned int n, const unsigned
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u += out[j]; out[j] = u;
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}
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/** Squares an unpacked integer */
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static void square(unsigned int out[32], const unsigned int a[32]) {
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unsigned int i;
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unsigned int j;
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@ -135,6 +146,7 @@ static void square(unsigned int out[32], const unsigned int a[32]) {
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squeeze(out);
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}
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/** Checks for the equality of two unpacked integers */
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static int check_equal(const unsigned int x[32], const unsigned int y[32]) {
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unsigned int differentbits = 0;
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int i;
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@ -147,6 +159,11 @@ static int check_equal(const unsigned int x[32], const unsigned int y[32]) {
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return (1 & ((differentbits - 1) >> 16));
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}
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/**
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* Checks if an unpacked integer equals zero
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*
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* The intergers must be must be \ref squeeze "squeezed" before.
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*/
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static int check_zero(const unsigned int x[32]) {
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static const unsigned int zero[32] = {0};
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static const unsigned int p[32] = {
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@ -159,6 +176,7 @@ static int check_zero(const unsigned int x[32]) {
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return (check_equal(x, zero) | check_equal(x, p));
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}
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/** Copies r to out when b == 0, s when b == 1 */
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static void selectw(ecc_25519_work_t *out, const ecc_25519_work_t *r, const ecc_25519_work_t *s, unsigned int b) {
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unsigned int j;
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unsigned int t;
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@ -180,6 +198,7 @@ static void selectw(ecc_25519_work_t *out, const ecc_25519_work_t *r, const ecc_
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}
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}
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/** Copies r to out when b == 0, s when b == 1 */
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static void select(unsigned int out[32], const unsigned int r[32], const unsigned int s[32], unsigned int b) {
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unsigned int j;
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unsigned int t;
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@ -192,6 +211,11 @@ static void select(unsigned int out[32], const unsigned int r[32], const unsigne
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}
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}
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/**
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* Computes the square root of an unpacked integer (in the prime field modulo p)
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*
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* If the given integer has no square root, the result is undefined.
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*/
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static void square_root(unsigned int out[32], const unsigned int z[32]) {
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static const unsigned int minus1[32] = {
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0xec, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
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@ -281,6 +305,7 @@ static void square_root(unsigned int out[32], const unsigned int z[32]) {
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select(out, z2_252_1, z2_252_1_rho_s, check_equal(t1, minus1));
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}
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/** Computes the reciprocal of an unpacked integer (in the prime field modulo p) */
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static void recip(unsigned int out[32], const unsigned int z[32]) {
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unsigned int z2[32];
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unsigned int z9[32];
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@ -347,6 +372,7 @@ static void recip(unsigned int out[32], const unsigned int z[32]) {
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/* 2^255 - 21 */ mult(out, t1, z11);
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}
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/** Loads a point with given coordinates into its unpacked representation */
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void ecc_25519_load_xy(ecc_25519_work_t *out, const ecc_int256_t *x, const ecc_int256_t *y) {
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int i;
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@ -359,6 +385,13 @@ void ecc_25519_load_xy(ecc_25519_work_t *out, const ecc_int256_t *x, const ecc_i
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mult(out->T, out->X, out->Y);
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}
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/**
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* Stores a point's x and y coordinates
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*
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* \param x Returns the x coordinate of the point. May be NULL.
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* \param y Returns the y coordinate of the point. May be NULL.
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* \param in The unpacked point to store.
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*/
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void ecc_25519_store_xy(ecc_int256_t *x, ecc_int256_t *y, const ecc_25519_work_t *in) {
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unsigned int X[32], Y[32], Z[32];
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int i;
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@ -380,6 +413,7 @@ void ecc_25519_store_xy(ecc_int256_t *x, ecc_int256_t *y, const ecc_25519_work_t
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}
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}
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/** Loads a packed point into its unpacked representation */
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void ecc_25519_load_packed(ecc_25519_work_t *out, const ecc_int256_t *in) {
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static const unsigned int zero[32] = {0};
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static const unsigned int one[32] = {1};
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@ -410,6 +444,7 @@ void ecc_25519_load_packed(ecc_25519_work_t *out, const ecc_int256_t *in) {
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mult(out->T, out->X, out->Y);
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}
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/** Stores a point into its packed representation */
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void ecc_25519_store_packed(ecc_int256_t *out, const ecc_25519_work_t *in) {
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ecc_int256_t y;
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@ -417,8 +452,10 @@ void ecc_25519_store_packed(ecc_int256_t *out, const ecc_25519_work_t *in) {
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out->p[31] |= (y.p[0] << 7);
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}
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/** The identity element */
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static const ecc_25519_work_t id = {{0}, {1}, {1}, {0}};
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/** Checks if a point is the identity element of the Elliptic Curve group */
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int ecc_25519_is_identity(const ecc_25519_work_t *in) {
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unsigned int Y_Z[32];
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@ -428,6 +465,13 @@ int ecc_25519_is_identity(const ecc_25519_work_t *in) {
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return (check_zero(in->X)&check_zero(Y_Z));
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}
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/**
|
||||
* Doubles a point of the Elliptic Curve
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*
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* ecc_25519_double(out, in) is equivalent to ecc_25519_add(out, in, in), but faster.
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*
|
||||
* The same pointers may be used for input and output.
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||||
*/
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void ecc_25519_double(ecc_25519_work_t *out, const ecc_25519_work_t *in) {
|
||||
unsigned int A[32], B[32], C[32], D[32], E[32], F[32], G[32], H[32], t0[32], t1[32], t2[32], t3[32];
|
||||
|
||||
|
|
@ -449,6 +493,11 @@ void ecc_25519_double(ecc_25519_work_t *out, const ecc_25519_work_t *in) {
|
|||
mult(out->Z, F, G);
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds two points of the Elliptic Curve
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
*/
|
||||
void ecc_25519_add(ecc_25519_work_t *out, const ecc_25519_work_t *in1, const ecc_25519_work_t *in2) {
|
||||
unsigned int A[32], B[32], C[32], D[32], E[32], F[32], G[32], H[32], t0[32], t1[32], t2[32], t3[32], t4[32], t5[32];
|
||||
|
||||
|
|
@ -472,6 +521,11 @@ void ecc_25519_add(ecc_25519_work_t *out, const ecc_25519_work_t *in1, const ecc
|
|||
mult(out->Z, F, G);
|
||||
}
|
||||
|
||||
/**
|
||||
* Does a scalar multiplication of a point of the Elliptic Curve with an integer
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
**/
|
||||
void ecc_25519_scalarmult(ecc_25519_work_t *out, const ecc_int256_t *n, const ecc_25519_work_t *base) {
|
||||
ecc_25519_work_t Q2, Q2p;
|
||||
ecc_25519_work_t cur = id;
|
||||
|
|
@ -489,6 +543,7 @@ void ecc_25519_scalarmult(ecc_25519_work_t *out, const ecc_int256_t *n, const ec
|
|||
*out = cur;
|
||||
}
|
||||
|
||||
/** The ec25519 default base */
|
||||
static const ecc_25519_work_t default_base = {
|
||||
{0xd4, 0x6b, 0xfe, 0x7f, 0x39, 0xfa, 0x8c, 0x22,
|
||||
0xe1, 0x96, 0x23, 0xeb, 0x26, 0xb7, 0x8e, 0x6a,
|
||||
|
|
@ -505,6 +560,11 @@ static const ecc_25519_work_t default_base = {
|
|||
0x47, 0x4b, 0x4c, 0x81, 0xa6, 0x02, 0xfd, 0x29}
|
||||
};
|
||||
|
||||
/**
|
||||
* Does a scalar multiplication of the default base point (generator element) of the Elliptic Curve with an integer
|
||||
*
|
||||
* The order of the base point is \f$ 2^{252} + 27742317777372353535851937790883648493 \f$.
|
||||
*/
|
||||
void ecc_25519_scalarmult_base(ecc_25519_work_t *out, const ecc_int256_t *n) {
|
||||
ecc_25519_scalarmult(out, n, &default_base);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -24,19 +24,27 @@
|
|||
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
*/
|
||||
|
||||
/*
|
||||
Simple finite field operations on the prime field F_q for
|
||||
q = 2^252 + 27742317777372353535851937790883648493, which
|
||||
/** \file
|
||||
Simple finite field operations on the prime field \f$ F_q \f$ for
|
||||
\f$ q = 2^{252} + 27742317777372353535851937790883648493 \f$, which
|
||||
is the order of the base point used for ec25519
|
||||
*/
|
||||
|
||||
#include <libuecc/ecc.h>
|
||||
|
||||
|
||||
/** Checks if the highest bit of an unsigned integer is set */
|
||||
#define IS_NEGATIVE(n) ((int)((((unsigned)n) >> (8*sizeof(n)-1))&1))
|
||||
|
||||
/** Performs an arithmetic right shift */
|
||||
#define ASR(n,s) (((n) >> s)|(IS_NEGATIVE(n)*((unsigned)-1) << (8*sizeof(n)-s)))
|
||||
|
||||
|
||||
/**
|
||||
* The order of the prime field
|
||||
*
|
||||
* The order is \f$ 2^{252} + 27742317777372353535851937790883648493 \f$.
|
||||
*/
|
||||
const ecc_int256_t ecc_25519_gf_order = {{
|
||||
0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58,
|
||||
0xd6, 0x9c, 0xf7, 0xa2, 0xde, 0xf9, 0xde, 0x14,
|
||||
|
|
@ -44,8 +52,12 @@ const ecc_int256_t ecc_25519_gf_order = {{
|
|||
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10
|
||||
}};
|
||||
|
||||
/** An internal alias for \ref ecc_25519_gf_order */
|
||||
static const unsigned char *q = ecc_25519_gf_order.p;
|
||||
|
||||
/**
|
||||
* Copies the content of r into out if b == 0, the contents of s if b == 1
|
||||
*/
|
||||
static void select(unsigned char out[32], const unsigned char r[32], const unsigned char s[32], unsigned int b) {
|
||||
unsigned int j;
|
||||
unsigned int t;
|
||||
|
|
@ -58,6 +70,7 @@ static void select(unsigned char out[32], const unsigned char r[32], const unsig
|
|||
}
|
||||
}
|
||||
|
||||
/** Checks if an integer is equal to zero (after reduction) */
|
||||
int ecc_25519_gf_is_zero(const ecc_int256_t *in) {
|
||||
int i;
|
||||
ecc_int256_t r;
|
||||
|
|
@ -71,6 +84,11 @@ int ecc_25519_gf_is_zero(const ecc_int256_t *in) {
|
|||
return (((bits-1)>>8) & 1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Adds two integers as Galois field elements
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
*/
|
||||
void ecc_25519_gf_add(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int256_t *in2) {
|
||||
unsigned int j;
|
||||
unsigned int u;
|
||||
|
|
@ -85,6 +103,11 @@ void ecc_25519_gf_add(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int2
|
|||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Subtracts two integers as Galois field elements
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
*/
|
||||
void ecc_25519_gf_sub(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int256_t *in2) {
|
||||
unsigned int j;
|
||||
unsigned int u;
|
||||
|
|
@ -99,6 +122,7 @@ void ecc_25519_gf_sub(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int2
|
|||
}
|
||||
}
|
||||
|
||||
/** Reduces an integer to a unique representation in the range \f$ [0,q-1] \f$ */
|
||||
static void reduce(unsigned char a[32]) {
|
||||
unsigned int j;
|
||||
unsigned int nq = a[31] >> 4;
|
||||
|
|
@ -121,6 +145,11 @@ static void reduce(unsigned char a[32]) {
|
|||
select(a, out1, out2, IS_NEGATIVE(u1));
|
||||
}
|
||||
|
||||
/**
|
||||
* Reduces an integer to a unique representation in the range \f$ [0,q-1] \f$
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
*/
|
||||
void ecc_25519_gf_reduce(ecc_int256_t *out, const ecc_int256_t *in) {
|
||||
int i;
|
||||
|
||||
|
|
@ -130,7 +159,7 @@ void ecc_25519_gf_reduce(ecc_int256_t *out, const ecc_int256_t *in) {
|
|||
reduce(out->p);
|
||||
}
|
||||
|
||||
/* Montgomery modular multiplication algorithm */
|
||||
/** Montgomery modular multiplication algorithm */
|
||||
static void montgomery(unsigned char out[32], const unsigned char a[32], const unsigned char b[32]) {
|
||||
unsigned int i, j;
|
||||
unsigned int nq;
|
||||
|
|
@ -154,7 +183,11 @@ static void montgomery(unsigned char out[32], const unsigned char a[32], const u
|
|||
}
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* Multiplies two integers as Galois field elements
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
*/
|
||||
void ecc_25519_gf_mult(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int256_t *in2) {
|
||||
/* 2^512 mod q */
|
||||
static const unsigned char C[32] = {
|
||||
|
|
@ -177,6 +210,11 @@ void ecc_25519_gf_mult(ecc_int256_t *out, const ecc_int256_t *in1, const ecc_int
|
|||
montgomery(out->p, R, C);
|
||||
}
|
||||
|
||||
/**
|
||||
* Computes the reciprocal of a Galois field element
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
*/
|
||||
void ecc_25519_gf_recip(ecc_int256_t *out, const ecc_int256_t *in) {
|
||||
static const unsigned char C[32] = {
|
||||
0x01
|
||||
|
|
@ -230,6 +268,11 @@ void ecc_25519_gf_recip(ecc_int256_t *out, const ecc_int256_t *in) {
|
|||
montgomery(out->p, R2, C);
|
||||
}
|
||||
|
||||
/**
|
||||
* Ensures some properties of a Galois field element to make it fit for use as a secret key
|
||||
*
|
||||
* The same pointers may be used for input and output.
|
||||
*/
|
||||
void ecc_25519_gf_sanitize_secret(ecc_int256_t *out, const ecc_int256_t *in) {
|
||||
int i;
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue