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Diffstat (limited to 'plugins/MirOTR/libotr/src/dh.h')
-rw-r--r-- | plugins/MirOTR/libotr/src/dh.h | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/plugins/MirOTR/libotr/src/dh.h b/plugins/MirOTR/libotr/src/dh.h new file mode 100644 index 0000000000..d68328f528 --- /dev/null +++ b/plugins/MirOTR/libotr/src/dh.h @@ -0,0 +1,119 @@ +/* + * Off-the-Record Messaging library + * Copyright (C) 2004-2008 Ian Goldberg, Chris Alexander, Nikita Borisov + * <otr@cypherpunks.ca> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of version 2.1 of the GNU Lesser General + * Public License as published by the Free Software Foundation. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef __DH_H__ +#define __DH_H__ + +#define DH1536_GROUP_ID 5 + +typedef struct { + unsigned int groupid; + gcry_mpi_t priv, pub; +} DH_keypair; + +/* Which half of the secure session id should be shown in bold? */ +typedef enum { + OTRL_SESSIONID_FIRST_HALF_BOLD, + OTRL_SESSIONID_SECOND_HALF_BOLD +} OtrlSessionIdHalf; + +typedef struct { + unsigned char sendctr[16]; + unsigned char rcvctr[16]; + gcry_cipher_hd_t sendenc; + gcry_cipher_hd_t rcvenc; + gcry_md_hd_t sendmac; + unsigned char sendmackey[20]; + int sendmacused; + gcry_md_hd_t rcvmac; + unsigned char rcvmackey[20]; + int rcvmacused; +} DH_sesskeys; + +/* + * Call this once, at plugin load time. It sets up the modulus and + * generator MPIs. + */ +void otrl_dh_init(void); + +/* + * Initialize the fields of a DH keypair. + */ +void otrl_dh_keypair_init(DH_keypair *kp); + +/* + * Copy a DH_keypair. + */ +void otrl_dh_keypair_copy(DH_keypair *dst, const DH_keypair *src); + +/* + * Deallocate the contents of a DH_keypair (but not the DH_keypair + * itself) + */ +void otrl_dh_keypair_free(DH_keypair *kp); + +/* + * Generate a DH keypair for a specified group. + */ +gcry_error_t otrl_dh_gen_keypair(unsigned int groupid, DH_keypair *kp); + +/* + * Construct session keys from a DH keypair and someone else's public + * key. + */ +gcry_error_t otrl_dh_session(DH_sesskeys *sess, const DH_keypair *kp, + gcry_mpi_t y); + +/* + * Compute the secure session id, two encryption keys, and four MAC keys + * given our DH key and their DH public key. + */ +gcry_error_t otrl_dh_compute_v2_auth_keys(const DH_keypair *our_dh, + gcry_mpi_t their_pub, unsigned char *sessionid, size_t *sessionidlenp, + gcry_cipher_hd_t *enc_c, gcry_cipher_hd_t *enc_cp, + gcry_md_hd_t *mac_m1, gcry_md_hd_t *mac_m1p, + gcry_md_hd_t *mac_m2, gcry_md_hd_t *mac_m2p); + +/* + * Compute the secure session id, given our DH key and their DH public + * key. + */ +gcry_error_t otrl_dh_compute_v1_session_id(const DH_keypair *our_dh, + gcry_mpi_t their_pub, unsigned char *sessionid, size_t *sessionidlenp, + OtrlSessionIdHalf *halfp); + +/* + * Deallocate the contents of a DH_sesskeys (but not the DH_sesskeys + * itself) + */ +void otrl_dh_session_free(DH_sesskeys *sess); + +/* + * Blank out the contents of a DH_sesskeys (without releasing it) + */ +void otrl_dh_session_blank(DH_sesskeys *sess); + +/* Increment the top half of a counter block */ +void otrl_dh_incctr(unsigned char *ctr); + +/* Compare two counter values (8 bytes each). Return 0 if ctr1 == ctr2, + * < 0 if ctr1 < ctr2 (as unsigned 64-bit values), > 0 if ctr1 > ctr2. */ +int otrl_dh_cmpctr(const unsigned char *ctr1, const unsigned char *ctr2); + +#endif |