diff options
Diffstat (limited to 'common')
| -rw-r--r-- | common/kem.c | 71 | ||||
| -rw-r--r-- | common/util.h | 21 |
2 files changed, 91 insertions, 1 deletions
diff --git a/common/kem.c b/common/kem.c index 65e533a83..5d994f0d6 100644 --- a/common/kem.c +++ b/common/kem.c @@ -35,7 +35,7 @@ #include <gpg-error.h> #include <gcrypt.h> #include "mischelp.h" - +#include "util.h" /* domSeperation as per *PGP specs. */ #define KMAC_KEY "OpenPGPCompositeKeyDerivationFunction" @@ -248,3 +248,72 @@ gnupg_kem_combiner (void *kek, size_t kek_len, KMAC_CUSTOM, strlen (KMAC_CUSTOM), iov, 6); return err; } + +#define ECC_CURVE25519_INDEX 0 +static const struct gnupg_ecc_params ecc_table[] = + { + { + "Curve25519", + 33, 32, 32, + GCRY_MD_SHA3_256, GCRY_KEM_RAW_X25519, + 1, 1 + }, + { + "X448", + 56, 56, 56, + GCRY_MD_SHA3_512, GCRY_KEM_RAW_X448, + 0, 0 + }, + { + "NIST P-256", + 65, 32, 65, + GCRY_MD_SHA3_256, GCRY_KEM_RAW_P256R1, + 0, 0 + }, + { + "NIST P-384", + 97, 48, 97, + GCRY_MD_SHA3_512, GCRY_KEM_RAW_P384R1, + 0, 0 + }, + { + "NIST P-521", + 133, 66, 133, + GCRY_MD_SHA3_512, GCRY_KEM_RAW_P521R1, + 0, 0 + }, + { + "brainpoolP256r1", + 65, 32, 65, + GCRY_MD_SHA3_256, GCRY_KEM_RAW_BP256, + 0, 0 + }, + { + "brainpoolP384r1", + 97, 48, 97, + GCRY_MD_SHA3_512, GCRY_KEM_RAW_BP384, + 0, 0 + }, + { + "brainpoolP512r1", + 129, 64, 129, + GCRY_MD_SHA3_512, GCRY_KEM_RAW_BP512, + 0, 0 + }, + { NULL, 0, 0, 0, 0, 0, 0, 0 } +}; + + +/* Return the ECC parameters for CURVE. CURVE is expected to be the + * canonical name. */ +const struct gnupg_ecc_params * +gnupg_get_ecc_params (const char *curve) +{ + int i; + + for (i = 0; ecc_table[i].curve; i++) + if (!strcmp (ecc_table[i].curve, curve)) + return &ecc_table[i]; + + return NULL; +} diff --git a/common/util.h b/common/util.h index b81664c3e..b13f4300d 100644 --- a/common/util.h +++ b/common/util.h @@ -324,6 +324,27 @@ gpg_error_t gnupg_kem_combiner (void *kek, size_t kek_len, const void *mlkem_ct, size_t mlkem_ct_len, const void *fixedinfo, size_t fixedinfo_len); +/* ECC parameters for KEM encryption/decryption. */ +struct gnupg_ecc_params +{ + const char *curve; /* Canonical name of the curve. */ + size_t pubkey_len; /* Pubkey length in the SEXP representation. */ + size_t scalar_len; + size_t point_len; + int hash_algo; /* Hash algo when it's used for composite KEM. */ + int kem_algo; + int scalar_reverse; /* Byte-oder is reverse. */ + int may_have_prefix; /* Point representation may have prefix. */ +}; + +const struct gnupg_ecc_params *gnupg_get_ecc_params (const char *curve); + +/* Maximum buffer sizes required for ECC KEM. */ +#define ECC_SCALAR_LEN_MAX 66 +#define ECC_POINT_LEN_MAX (1+2*ECC_SCALAR_LEN_MAX) +#define ECC_HASH_LEN_MAX 64 + + /*-- miscellaneous.c --*/ /* This function is called at startup to tell libgcrypt to use our own |