diff options
Diffstat (limited to 'libtomcrypt/src/pk/dsa/dsa_set.c')
| -rw-r--r-- | libtomcrypt/src/pk/dsa/dsa_set.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/dsa/dsa_set.c b/libtomcrypt/src/pk/dsa/dsa_set.c new file mode 100644 index 0000000..a4d4042 --- /dev/null +++ b/libtomcrypt/src/pk/dsa/dsa_set.c @@ -0,0 +1,112 @@ +/* LibTomCrypt, modular cryptographic library -- Tom St Denis + * + * LibTomCrypt is a library that provides various cryptographic + * algorithms in a highly modular and flexible manner. + * + * The library is free for all purposes without any express + * guarantee it works. + */ +#include "tomcrypt.h" + + +#ifdef LTC_MDSA + +/** + Import DSA's p, q & g from raw numbers + @param p DSA's p in binary representation + @param plen The length of p + @param q DSA's q in binary representation + @param qlen The length of q + @param g DSA's g in binary representation + @param glen The length of g + @param key [out] the destination for the imported key + @return CRYPT_OK if successful. +*/ +int dsa_set_pqg(const unsigned char *p, unsigned long plen, + const unsigned char *q, unsigned long qlen, + const unsigned char *g, unsigned long glen, + dsa_key *key) +{ + int err, stat; + + LTC_ARGCHK(p != NULL); + LTC_ARGCHK(q != NULL); + LTC_ARGCHK(g != NULL); + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(ltc_mp.name != NULL); + + /* init key */ + err = mp_init_multi(&key->p, &key->g, &key->q, &key->x, &key->y, NULL); + if (err != CRYPT_OK) return err; + + if ((err = mp_read_unsigned_bin(key->p, (unsigned char *)p , plen)) != CRYPT_OK) { goto LBL_ERR; } + if ((err = mp_read_unsigned_bin(key->g, (unsigned char *)g , glen)) != CRYPT_OK) { goto LBL_ERR; } + if ((err = mp_read_unsigned_bin(key->q, (unsigned char *)q , qlen)) != CRYPT_OK) { goto LBL_ERR; } + + key->qord = mp_unsigned_bin_size(key->q); + + /* do only a quick validation, without primality testing */ + if ((err = dsa_int_validate_pqg(key, &stat)) != CRYPT_OK) { goto LBL_ERR; } + if (stat == 0) { + err = CRYPT_INVALID_PACKET; + goto LBL_ERR; + } + + return CRYPT_OK; + +LBL_ERR: + dsa_free(key); + return err; +} + +/** + Import DSA public or private key-part from raw numbers + + NB: The p, q & g parts must be set beforehand + + @param in The key-part to import, either public or private. + @param inlen The key-part's length + @param type Which type of key (PK_PRIVATE or PK_PUBLIC) + @param key [out] the destination for the imported key + @return CRYPT_OK if successful. +*/ +int dsa_set_key(const unsigned char *in, unsigned long inlen, int type, dsa_key *key) +{ + int err, stat = 0; + + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(key->x != NULL); + LTC_ARGCHK(key->y != NULL); + LTC_ARGCHK(key->p != NULL); + LTC_ARGCHK(key->g != NULL); + LTC_ARGCHK(key->q != NULL); + LTC_ARGCHK(ltc_mp.name != NULL); + + if (type == PK_PRIVATE) { + key->type = PK_PRIVATE; + if ((err = mp_read_unsigned_bin(key->x, (unsigned char *)in, inlen)) != CRYPT_OK) { goto LBL_ERR; } + if ((err = mp_exptmod(key->g, key->x, key->p, key->y)) != CRYPT_OK) { goto LBL_ERR; } + } + else { + key->type = PK_PUBLIC; + if ((err = mp_read_unsigned_bin(key->y, (unsigned char *)in, inlen)) != CRYPT_OK) { goto LBL_ERR; } + } + + if ((err = dsa_int_validate_xy(key, &stat)) != CRYPT_OK) { goto LBL_ERR; } + if (stat == 0) { + err = CRYPT_INVALID_PACKET; + goto LBL_ERR; + } + + return CRYPT_OK; + +LBL_ERR: + dsa_free(key); + return err; +} + +#endif + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */ |