diff options
Diffstat (limited to 'include/linux/mpi.h')
-rw-r--r-- | include/linux/mpi.h | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/include/linux/mpi.h b/include/linux/mpi.h index 3c9e41603cf6..3e5358f4de2f 100644 --- a/include/linux/mpi.h +++ b/include/linux/mpi.h @@ -157,6 +157,111 @@ void mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor); /*-- mpi-inv.c --*/ int mpi_invm(MPI x, MPI a, MPI n); +/*-- ec.c --*/ + +/* Object to represent a point in projective coordinates */ +struct gcry_mpi_point { + MPI x; + MPI y; + MPI z; +}; + +typedef struct gcry_mpi_point *MPI_POINT; + +/* Models describing an elliptic curve */ +enum gcry_mpi_ec_models { + /* The Short Weierstrass equation is + * y^2 = x^3 + ax + b + */ + MPI_EC_WEIERSTRASS = 0, + /* The Montgomery equation is + * by^2 = x^3 + ax^2 + x + */ + MPI_EC_MONTGOMERY, + /* The Twisted Edwards equation is + * ax^2 + y^2 = 1 + bx^2y^2 + * Note that we use 'b' instead of the commonly used 'd'. + */ + MPI_EC_EDWARDS +}; + +/* Dialects used with elliptic curves */ +enum ecc_dialects { + ECC_DIALECT_STANDARD = 0, + ECC_DIALECT_ED25519, + ECC_DIALECT_SAFECURVE +}; + +/* This context is used with all our EC functions. */ +struct mpi_ec_ctx { + enum gcry_mpi_ec_models model; /* The model describing this curve. */ + enum ecc_dialects dialect; /* The ECC dialect used with the curve. */ + int flags; /* Public key flags (not always used). */ + unsigned int nbits; /* Number of bits. */ + + /* Domain parameters. Note that they may not all be set and if set + * the MPIs may be flaged as constant. + */ + MPI p; /* Prime specifying the field GF(p). */ + MPI a; /* First coefficient of the Weierstrass equation. */ + MPI b; /* Second coefficient of the Weierstrass equation. */ + MPI_POINT G; /* Base point (generator). */ + MPI n; /* Order of G. */ + unsigned int h; /* Cofactor. */ + + /* The actual key. May not be set. */ + MPI_POINT Q; /* Public key. */ + MPI d; /* Private key. */ + + const char *name; /* Name of the curve. */ + + /* This structure is private to mpi/ec.c! */ + struct { + struct { + unsigned int a_is_pminus3:1; + unsigned int two_inv_p:1; + } valid; /* Flags to help setting the helper vars below. */ + + int a_is_pminus3; /* True if A = P - 3. */ + + MPI two_inv_p; + + mpi_barrett_t p_barrett; + + /* Scratch variables. */ + MPI scratch[11]; + + /* Helper for fast reduction. */ + /* int nist_nbits; /\* If this is a NIST curve, the # of bits. *\/ */ + /* MPI s[10]; */ + /* MPI c; */ + } t; + + /* Curve specific computation routines for the field. */ + void (*addm)(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx); + void (*subm)(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ec); + void (*mulm)(MPI w, MPI u, MPI v, struct mpi_ec_ctx *ctx); + void (*pow2)(MPI w, const MPI b, struct mpi_ec_ctx *ctx); + void (*mul2)(MPI w, MPI u, struct mpi_ec_ctx *ctx); +}; + +void mpi_ec_init(struct mpi_ec_ctx *ctx, enum gcry_mpi_ec_models model, + enum ecc_dialects dialect, + int flags, MPI p, MPI a, MPI b); +void mpi_ec_deinit(struct mpi_ec_ctx *ctx); +MPI_POINT mpi_point_new(unsigned int nbits); +void mpi_point_release(MPI_POINT p); +void mpi_point_init(MPI_POINT p); +void mpi_point_free_parts(MPI_POINT p); +int mpi_ec_get_affine(MPI x, MPI y, MPI_POINT point, struct mpi_ec_ctx *ctx); +void mpi_ec_add_points(MPI_POINT result, + MPI_POINT p1, MPI_POINT p2, + struct mpi_ec_ctx *ctx); +void mpi_ec_mul_point(MPI_POINT result, + MPI scalar, MPI_POINT point, + struct mpi_ec_ctx *ctx); +int mpi_ec_curve_point(MPI_POINT point, struct mpi_ec_ctx *ctx); + /* inline functions */ /** |