diff options
Diffstat (limited to 'libtomcrypt/src/pk/dsa/dsa_import.c')
-rw-r--r-- | libtomcrypt/src/pk/dsa/dsa_import.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/dsa/dsa_import.c b/libtomcrypt/src/pk/dsa/dsa_import.c new file mode 100644 index 0000000..bb2272a --- /dev/null +++ b/libtomcrypt/src/pk/dsa/dsa_import.c @@ -0,0 +1,90 @@ +/* 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. + * + * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com + */ +#include "tomcrypt.h" + +/** + @file dsa_import.c + DSA implementation, import a DSA key, Tom St Denis +*/ + +#ifdef MDSA + +/** + Import a DSA key + @param in The binary packet to import from + @param inlen The length of the binary packet + @param key [out] Where to store the imported key + @return CRYPT_OK if successful, upon error this function will free all allocated memory +*/ +int dsa_import(const unsigned char *in, unsigned long inlen, dsa_key *key) +{ + unsigned char flags[1]; + int err; + + LTC_ARGCHK(in != NULL); + LTC_ARGCHK(key != NULL); + LTC_ARGCHK(ltc_mp.name != NULL); + + /* init key */ + if (mp_init_multi(&key->p, &key->g, &key->q, &key->x, &key->y, NULL) != CRYPT_OK) { + return CRYPT_MEM; + } + + /* get key type */ + if ((err = der_decode_sequence_multi(in, inlen, + LTC_ASN1_BIT_STRING, 1UL, flags, + LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) { + goto error; + } + + if (flags[0] == 1) { + if ((err = der_decode_sequence_multi(in, inlen, + LTC_ASN1_BIT_STRING, 1UL, flags, + LTC_ASN1_INTEGER, 1UL, key->g, + LTC_ASN1_INTEGER, 1UL, key->p, + LTC_ASN1_INTEGER, 1UL, key->q, + LTC_ASN1_INTEGER, 1UL, key->y, + LTC_ASN1_INTEGER, 1UL, key->x, + LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) { + goto error; + } + key->type = PK_PRIVATE; + } else { + if ((err = der_decode_sequence_multi(in, inlen, + LTC_ASN1_BIT_STRING, 1UL, flags, + LTC_ASN1_INTEGER, 1UL, key->g, + LTC_ASN1_INTEGER, 1UL, key->p, + LTC_ASN1_INTEGER, 1UL, key->q, + LTC_ASN1_INTEGER, 1UL, key->y, + LTC_ASN1_EOL, 0UL, NULL)) != CRYPT_OK) { + goto error; + } + key->type = PK_PUBLIC; + } + key->qord = mp_unsigned_bin_size(key->q); + + if (key->qord >= MDSA_MAX_GROUP || key->qord <= 15 || + (unsigned long)key->qord >= mp_unsigned_bin_size(key->p) || (mp_unsigned_bin_size(key->p) - key->qord) >= MDSA_DELTA) { + err = CRYPT_INVALID_PACKET; + goto error; + } + + return CRYPT_OK; +error: + mp_clear_multi(key->p, key->g, key->q, key->x, key->y, NULL); + return err; +} + +#endif + +/* $Source: /cvs/libtom/libtomcrypt/src/pk/dsa/dsa_import.c,v $ */ +/* $Revision: 1.12 $ */ +/* $Date: 2006/03/31 14:15:35 $ */ |