diff options
Diffstat (limited to 'libtomcrypt/src/pk/dh/dh_export.c')
| -rw-r--r-- | libtomcrypt/src/pk/dh/dh_export.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/libtomcrypt/src/pk/dh/dh_export.c b/libtomcrypt/src/pk/dh/dh_export.c new file mode 100644 index 0000000..6a02a89 --- /dev/null +++ b/libtomcrypt/src/pk/dh/dh_export.c @@ -0,0 +1,62 @@ +/* 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_MDH + +/** + Export a DH key to a binary packet + @param out [out] The destination for the key + @param outlen [in/out] The max size and resulting size of the DH key + @param type Which type of key (PK_PRIVATE or PK_PUBLIC) + @param key The key you wish to export + @return CRYPT_OK if successful +*/ +int dh_export(unsigned char *out, unsigned long *outlen, int type, dh_key *key) +{ + unsigned char flags[1]; + int err; + unsigned long version = 0; + + LTC_ARGCHK(out != NULL); + LTC_ARGCHK(outlen != NULL); + LTC_ARGCHK(key != NULL); + + if (type == PK_PRIVATE) { + /* export x - private key */ + flags[0] = 1; + err = der_encode_sequence_multi(out, outlen, + LTC_ASN1_SHORT_INTEGER, 1UL, &version, + LTC_ASN1_BIT_STRING, 1UL, flags, + LTC_ASN1_INTEGER, 1UL, key->prime, + LTC_ASN1_INTEGER, 1UL, key->base, + LTC_ASN1_INTEGER, 1UL, key->x, + LTC_ASN1_EOL, 0UL, NULL); + } + else { + /* export y - public key */ + flags[0] = 0; + err = der_encode_sequence_multi(out, outlen, + LTC_ASN1_SHORT_INTEGER, 1UL, &version, + LTC_ASN1_BIT_STRING, 1UL, flags, + LTC_ASN1_INTEGER, 1UL, key->prime, + LTC_ASN1_INTEGER, 1UL, key->base, + LTC_ASN1_INTEGER, 1UL, key->y, + LTC_ASN1_EOL, 0UL, NULL); + } + + return err; +} + +#endif /* LTC_MDH */ + +/* ref: $Format:%D$ */ +/* git commit: $Format:%H$ */ +/* commit time: $Format:%ai$ */ |