diff options
Diffstat (limited to 'libotr/libotr-4.1.1/src/auth.c')
-rw-r--r-- | libotr/libotr-4.1.1/src/auth.c | 1573 |
1 files changed, 1573 insertions, 0 deletions
diff --git a/libotr/libotr-4.1.1/src/auth.c b/libotr/libotr-4.1.1/src/auth.c new file mode 100644 index 0000000..d0c5505 --- /dev/null +++ b/libotr/libotr-4.1.1/src/auth.c @@ -0,0 +1,1573 @@ +/* + * Off-the-Record Messaging library + * Copyright (C) 2004-2014 Ian Goldberg, David Goulet, Rob Smits, + * Chris Alexander, Willy Lew, Lisa Du, + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* system headers */ +#include <stdlib.h> +#include <string.h> +#include <assert.h> + +/* libotr headers */ +#include "b64.h" +#include "privkey.h" +#include "auth.h" +#include "serial.h" +#include "proto.h" +#include "context.h" +#include "mem.h" + +#if OTRL_DEBUGGING +#include <stdio.h> + +/* Dump the contents of an OtrlAuthInfo to the FILE *f. */ +void otrl_auth_dump(FILE *f, const OtrlAuthInfo *auth) +{ + int i; + + fprintf(f, " Auth info %p:\n", auth); + fprintf(f, " State: %d (%s)\n", auth->authstate, + auth->authstate == OTRL_AUTHSTATE_NONE ? "NONE" : + auth->authstate == OTRL_AUTHSTATE_AWAITING_DHKEY ? "AWAITING_DHKEY" : + auth->authstate == OTRL_AUTHSTATE_AWAITING_REVEALSIG ? + "AWAITING_REVEALSIG" : + auth->authstate == OTRL_AUTHSTATE_AWAITING_SIG ? "AWAITING_SIG" : + auth->authstate == OTRL_AUTHSTATE_V1_SETUP ? "V1_SETUP" : + "INVALID"); + fprintf(f, " Context: %p\n", auth->context); + fprintf(f, " Our keyid: %u\n", auth->our_keyid); + fprintf(f, " Their keyid: %u\n", auth->their_keyid); + fprintf(f, " Their fingerprint: "); + for (i=0;i<20;++i) { + fprintf(f, "%02x", auth->their_fingerprint[i]); + } + fprintf(f, "\n Initiated = %d\n", auth->initiated); + fprintf(f, "\n Proto version = %d\n", auth->protocol_version); + fprintf(f, "\n Lastauthmsg = %s\n", + auth->lastauthmsg ? auth->lastauthmsg : "(nil)"); + fprintf(f, "\n Commit sent time = %ld\n", + (long) auth->commit_sent_time); +} + +#endif + +/* + * Initialize the fields of an OtrlAuthInfo (already allocated). + */ +void otrl_auth_new(struct context *context) +{ + OtrlAuthInfo *auth = &(context->auth); + auth->authstate = OTRL_AUTHSTATE_NONE; + otrl_dh_keypair_init(&(auth->our_dh)); + auth->our_keyid = 0; + auth->encgx = NULL; + auth->encgx_len = 0; + memset(auth->r, 0, 16); + memset(auth->hashgx, 0, 32); + auth->their_pub = NULL; + auth->their_keyid = 0; + auth->enc_c = NULL; + auth->enc_cp = NULL; + auth->mac_m1 = NULL; + auth->mac_m1p = NULL; + auth->mac_m2 = NULL; + auth->mac_m2p = NULL; + memset(auth->their_fingerprint, 0, 20); + auth->initiated = 0; + auth->protocol_version = 0; + memset(auth->secure_session_id, 0, 20); + auth->secure_session_id_len = 0; + auth->lastauthmsg = NULL; + auth->commit_sent_time = 0; + auth->context = context; +} + +/* + * Clear the fields of an OtrlAuthInfo (but leave it allocated). + */ +void otrl_auth_clear(OtrlAuthInfo *auth) +{ + auth->authstate = OTRL_AUTHSTATE_NONE; + otrl_dh_keypair_free(&(auth->our_dh)); + auth->our_keyid = 0; + free(auth->encgx); + auth->encgx = NULL; + auth->encgx_len = 0; + memset(auth->r, 0, 16); + memset(auth->hashgx, 0, 32); + gcry_mpi_release(auth->their_pub); + auth->their_pub = NULL; + auth->their_keyid = 0; + gcry_cipher_close(auth->enc_c); + gcry_cipher_close(auth->enc_cp); + gcry_md_close(auth->mac_m1); + gcry_md_close(auth->mac_m1p); + gcry_md_close(auth->mac_m2); + gcry_md_close(auth->mac_m2p); + auth->enc_c = NULL; + auth->enc_cp = NULL; + auth->mac_m1 = NULL; + auth->mac_m1p = NULL; + auth->mac_m2 = NULL; + auth->mac_m2p = NULL; + memset(auth->their_fingerprint, 0, 20); + auth->initiated = 0; + auth->protocol_version = 0; + memset(auth->secure_session_id, 0, 20); + auth->secure_session_id_len = 0; + free(auth->lastauthmsg); + auth->lastauthmsg = NULL; + auth->commit_sent_time = 0; +} + +/* + * Start a fresh AKE (version 2 or 3) using the given OtrlAuthInfo. Generate + * a fresh DH keypair to use. If no error is returned, the message to + * transmit will be contained in auth->lastauthmsg. + */ +gcry_error_t otrl_auth_start_v23(OtrlAuthInfo *auth, int version) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + const enum gcry_mpi_format format = GCRYMPI_FMT_USG; + size_t npub; + gcry_cipher_hd_t enc = NULL; + unsigned char ctr[16]; + unsigned char *buf, *bufp; + size_t buflen, lenp; + + /* Clear out this OtrlAuthInfo and start over */ + otrl_auth_clear(auth); + auth->initiated = 1; + auth->protocol_version = version; + auth->context->protocol_version = version; + + otrl_dh_gen_keypair(DH1536_GROUP_ID, &(auth->our_dh)); + auth->our_keyid = 1; + + /* Pick an encryption key */ + gcry_randomize(auth->r, 16, GCRY_STRONG_RANDOM); + + /* Allocate space for the encrypted g^x */ + gcry_mpi_print(format, NULL, 0, &npub, auth->our_dh.pub); + auth->encgx = malloc(4+npub); + if (auth->encgx == NULL) goto memerr; + auth->encgx_len = 4+npub; + bufp = auth->encgx; + lenp = auth->encgx_len; + write_mpi(auth->our_dh.pub, npub, "g^x"); + assert(lenp == 0); + + /* Hash g^x */ + gcry_md_hash_buffer(GCRY_MD_SHA256, auth->hashgx, auth->encgx, + auth->encgx_len); + + /* Encrypt g^x using the key r */ + err = gcry_cipher_open(&enc, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CTR, + GCRY_CIPHER_SECURE); + if (err) goto err; + + err = gcry_cipher_setkey(enc, auth->r, 16); + if (err) goto err; + + memset(ctr, 0, 16); + err = gcry_cipher_setctr(enc, ctr, 16); + if (err) goto err; + + err = gcry_cipher_encrypt(enc, auth->encgx, auth->encgx_len, NULL, 0); + if (err) goto err; + + gcry_cipher_close(enc); + enc = NULL; + + /* Now serialize the message */ + lenp = OTRL_HEADER_LEN + (auth->protocol_version == 3 ? 8 : 0) + 4 + + auth->encgx_len + 4 + 32; + bufp = malloc(lenp); + if (bufp == NULL) goto memerr; + buf = bufp; + buflen = lenp; + + /* Header */ + write_header(auth->protocol_version, '\x02'); + if (auth->protocol_version == 3) { + /* instance tags */ + write_int(auth->context->our_instance); + debug_int("Sender instag", bufp-4); + write_int(auth->context->their_instance); + debug_int("Recipient instag", bufp-4); + } + + /* Encrypted g^x */ + write_int(auth->encgx_len); + debug_int("Enc gx len", bufp-4); + memmove(bufp, auth->encgx, auth->encgx_len); + debug_data("Enc gx", bufp, auth->encgx_len); + bufp += auth->encgx_len; lenp -= auth->encgx_len; + + /* Hashed g^x */ + write_int(32); + debug_int("hashgx len", bufp-4); + memmove(bufp, auth->hashgx, 32); + debug_data("hashgx", bufp, 32); + bufp += 32; lenp -= 32; + + assert(lenp == 0); + + auth->lastauthmsg = otrl_base64_otr_encode(buf, buflen); + free(buf); + if (auth->lastauthmsg == NULL) goto memerr; + auth->authstate = OTRL_AUTHSTATE_AWAITING_DHKEY; + + return err; + +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + otrl_auth_clear(auth); + gcry_cipher_close(enc); + return err; +} + +/* + * Create a D-H Key Message using the our_dh value in the given auth, + * and store it in auth->lastauthmsg. + */ +static gcry_error_t create_key_message(OtrlAuthInfo *auth) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + const enum gcry_mpi_format format = GCRYMPI_FMT_USG; + unsigned char *buf, *bufp; + size_t buflen, lenp; + size_t npub; + + gcry_mpi_print(format, NULL, 0, &npub, auth->our_dh.pub); + buflen = OTRL_HEADER_LEN + (auth->protocol_version == 3 ? 8 : 0) + 4 + npub; + buf = malloc(buflen); + if (buf == NULL) goto memerr; + bufp = buf; + lenp = buflen; + + /* header */ + write_header(auth->protocol_version, '\x0a'); + if (auth->protocol_version == 3) { + /* instance tags */ + write_int(auth->context->our_instance); + debug_int("Sender instag", bufp-4); + write_int(auth->context->their_instance); + debug_int("Recipient instag", bufp-4); + } + + /* g^y */ + write_mpi(auth->our_dh.pub, npub, "g^y"); + + assert(lenp == 0); + + free(auth->lastauthmsg); + auth->lastauthmsg = otrl_base64_otr_encode(buf, buflen); + free(buf); + if (auth->lastauthmsg == NULL) goto memerr; + + return err; + +memerr: + err = gcry_error(GPG_ERR_ENOMEM); + return err; +} + +/* + * Handle an incoming D-H Commit Message. If no error is returned, the + * message to send will be left in auth->lastauthmsg. Generate a fresh + * keypair to use. + */ +gcry_error_t otrl_auth_handle_commit(OtrlAuthInfo *auth, + const char *commitmsg, int version) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + unsigned char *buf = NULL, *bufp = NULL, *encbuf = NULL; + unsigned char hashbuf[32]; + size_t buflen, lenp, enclen, hashlen; + int res; + + /* Are we the auth for the master context? */ + int is_master = (auth->context->m_context == auth->context); + + res = otrl_base64_otr_decode(commitmsg, &buf, &buflen); + if (res == -1) goto memerr; + if (res == -2) goto invval; + + bufp = buf; + lenp = buflen; + + /* Header */ + auth->protocol_version = version; + auth->context->protocol_version = version; + skip_header('\x02'); + + if (version == 3) { + require_len(8); + bufp += 8; lenp -= 8; + } + + /* Encrypted g^x */ + read_int(enclen); + require_len(enclen); + encbuf = malloc(enclen); + if (encbuf == NULL && enclen > 0) goto memerr; + memmove(encbuf, bufp, enclen); + bufp += enclen; lenp -= enclen; + + /* Hashed g^x */ + read_int(hashlen); + if (hashlen != 32) goto invval; + require_len(32); + memmove(hashbuf, bufp, 32); + bufp += 32; lenp -= 32; + + if (lenp != 0) goto invval; + free(buf); + buf = NULL; + + switch(auth->authstate) { + case OTRL_AUTHSTATE_NONE: + case OTRL_AUTHSTATE_AWAITING_SIG: + case OTRL_AUTHSTATE_V1_SETUP: + /* Store the incoming information */ + otrl_auth_clear(auth); + auth->protocol_version = version; + + otrl_dh_gen_keypair(DH1536_GROUP_ID, &(auth->our_dh)); + + auth->our_keyid = 1; + auth->encgx = encbuf; + encbuf = NULL; + auth->encgx_len = enclen; + memmove(auth->hashgx, hashbuf, 32); + + /* Create a D-H Key Message */ + err = create_key_message(auth); + if (err) goto err; + auth->authstate = OTRL_AUTHSTATE_AWAITING_REVEALSIG; + break; + + case OTRL_AUTHSTATE_AWAITING_DHKEY: + /* We sent a D-H Commit Message, and we also received one + * back. If we're the master context, then the keypair in here + * is probably stale; we just kept it around for a little + * while in case some other logged in instance of our buddy + * replied with a DHKEY message. In that case, use the + * incoming parameters. Otherwise, compare the hashgx + * values to see which one wins. + * + * This does NOT use constant time comparison because these + * are two public values thus don't need it. Also, this checks + * which pubkey is larger and not if they are the same. */ + if (!is_master && memcmp(auth->hashgx, hashbuf, 32) > 0) { + /* Ours wins. Ignore the message we received, and just + * resend the same D-H Commit message again. */ + free(encbuf); + encbuf = NULL; + } else { + /* Ours loses. Use the incoming parameters instead. */ + otrl_auth_clear(auth); + auth->protocol_version = version; + otrl_dh_gen_keypair(DH1536_GROUP_ID, &(auth->our_dh)); + auth->our_keyid = 1; + auth->encgx = encbuf; + encbuf = NULL; + auth->encgx_len = enclen; + memmove(auth->hashgx, hashbuf, 32); + + /* Create a D-H Key Message */ + err = create_key_message(auth); + if (err) goto err; + auth->authstate = OTRL_AUTHSTATE_AWAITING_REVEALSIG; + } + break; + case OTRL_AUTHSTATE_AWAITING_REVEALSIG: + /* Use the incoming parameters, but just retransmit the old + * D-H Key Message. */ + free(auth->encgx); + auth->encgx = encbuf; + encbuf = NULL; + auth->encgx_len = enclen; + memmove(auth->hashgx, hashbuf, 32); + break; + } + + return err; + +invval: + err = gcry_error(GPG_ERR_INV_VALUE); + goto err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + free(encbuf); + return err; +} + +/* + * Calculate the encrypted part of the Reveal Signature and Signature + * Messages, given a MAC key, an encryption key, two DH public keys, an + * authentication public key (contained in an OtrlPrivKey structure), + * and a keyid. If no error is returned, *authbufp will point to the + * result, and *authlenp will point to its length. + */ +static gcry_error_t calculate_pubkey_auth(unsigned char **authbufp, + size_t *authlenp, gcry_md_hd_t mackey, gcry_cipher_hd_t enckey, + gcry_mpi_t our_dh_pub, gcry_mpi_t their_dh_pub, + OtrlPrivKey *privkey, unsigned int keyid) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + const enum gcry_mpi_format format = GCRYMPI_FMT_USG; + size_t ourpublen, theirpublen, totallen, lenp; + unsigned char *buf = NULL, *bufp = NULL; + unsigned char macbuf[32]; + unsigned char *sigbuf = NULL; + size_t siglen; + + /* How big are the DH public keys? */ + gcry_mpi_print(format, NULL, 0, &ourpublen, our_dh_pub); + gcry_mpi_print(format, NULL, 0, &theirpublen, their_dh_pub); + + /* How big is the total structure to be MAC'd? */ + totallen = 4 + ourpublen + 4 + theirpublen + 2 + privkey->pubkey_datalen + + 4; + buf = malloc(totallen); + if (buf == NULL) goto memerr; + + bufp = buf; + lenp = totallen; + + /* Write the data to be MAC'd */ + write_mpi(our_dh_pub, ourpublen, "Our DH pubkey"); + write_mpi(their_dh_pub, theirpublen, "Their DH pubkey"); + bufp[0] = ((privkey->pubkey_type) >> 8) & 0xff; + bufp[1] = (privkey->pubkey_type) & 0xff; + bufp += 2; lenp -= 2; + memmove(bufp, privkey->pubkey_data, privkey->pubkey_datalen); + debug_data("Pubkey", bufp, privkey->pubkey_datalen); + bufp += privkey->pubkey_datalen; lenp -= privkey->pubkey_datalen; + write_int(keyid); + debug_int("Keyid", bufp-4); + + assert(lenp == 0); + + /* Do the MAC */ + gcry_md_reset(mackey); + gcry_md_write(mackey, buf, totallen); + memmove(macbuf, gcry_md_read(mackey, GCRY_MD_SHA256), 32); + + free(buf); + buf = NULL; + + /* Sign the MAC */ + err = otrl_privkey_sign(&sigbuf, &siglen, privkey, macbuf, 32); + if (err) goto err; + + /* Calculate the total size of the structure to be encrypted */ + totallen = 2 + privkey->pubkey_datalen + 4 + siglen; + buf = malloc(totallen); + if (buf == NULL) goto memerr; + bufp = buf; + lenp = totallen; + + /* Write the data to be encrypted */ + bufp[0] = ((privkey->pubkey_type) >> 8) & 0xff; + bufp[1] = (privkey->pubkey_type) & 0xff; + bufp += 2; lenp -= 2; + memmove(bufp, privkey->pubkey_data, privkey->pubkey_datalen); + debug_data("Pubkey", bufp, privkey->pubkey_datalen); + bufp += privkey->pubkey_datalen; lenp -= privkey->pubkey_datalen; + write_int(keyid); + debug_int("Keyid", bufp-4); + memmove(bufp, sigbuf, siglen); + debug_data("Signature", bufp, siglen); + bufp += siglen; lenp -= siglen; + free(sigbuf); + sigbuf = NULL; + + assert(lenp == 0); + + /* Now do the encryption */ + err = gcry_cipher_encrypt(enckey, buf, totallen, NULL, 0); + if (err) goto err; + + *authbufp = buf; + buf = NULL; + *authlenp = totallen; + + return err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + free(sigbuf); + return err; +} + +/* + * Decrypt the authenticator in the Reveal Signature and Signature + * Messages, given a MAC key, and encryption key, and two DH public + * keys. The fingerprint of the received public key will get put into + * fingerprintbufp, and the received keyid will get put in *keyidp. + * The encrypted data pointed to by authbuf will be decrypted in place. + */ +static gcry_error_t check_pubkey_auth(unsigned char fingerprintbufp[20], + unsigned int *keyidp, unsigned char *authbuf, size_t authlen, + gcry_md_hd_t mackey, gcry_cipher_hd_t enckey, + gcry_mpi_t our_dh_pub, gcry_mpi_t their_dh_pub) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + const enum gcry_mpi_format format = GCRYMPI_FMT_USG; + size_t ourpublen, theirpublen, totallen, lenp; + unsigned char *buf = NULL, *bufp = NULL; + unsigned char macbuf[32]; + unsigned short pubkey_type; + gcry_mpi_t p,q,g,y; + gcry_sexp_t pubs = NULL; + unsigned int received_keyid; + unsigned char *fingerprintstart, *fingerprintend, *sigbuf; + size_t siglen; + + /* Start by decrypting it */ + err = gcry_cipher_decrypt(enckey, authbuf, authlen, NULL, 0); + if (err) goto err; + + bufp = authbuf; + lenp = authlen; + + /* Get the public key and calculate its fingerprint */ + require_len(2); + pubkey_type = (bufp[0] << 8) + bufp[1]; + bufp += 2; lenp -= 2; + if (pubkey_type != OTRL_PUBKEY_TYPE_DSA) goto invval; + fingerprintstart = bufp; + read_mpi(p); + read_mpi(q); + read_mpi(g); + read_mpi(y); + fingerprintend = bufp; + gcry_md_hash_buffer(GCRY_MD_SHA1, fingerprintbufp, + fingerprintstart, fingerprintend-fingerprintstart); + gcry_sexp_build(&pubs, NULL, + "(public-key (dsa (p %m)(q %m)(g %m)(y %m)))", p, q, g, y); + gcry_mpi_release(p); + gcry_mpi_release(q); + gcry_mpi_release(g); + gcry_mpi_release(y); + + /* Get the keyid */ + read_int(received_keyid); + if (received_keyid == 0) goto invval; + + /* Get the signature */ + sigbuf = bufp; + siglen = lenp; + + /* How big are the DH public keys? */ + gcry_mpi_print(format, NULL, 0, &ourpublen, our_dh_pub); + gcry_mpi_print(format, NULL, 0, &theirpublen, their_dh_pub); + + /* Now calculate the message to be MAC'd. */ + totallen = 4 + ourpublen + 4 + theirpublen + 2 + + (fingerprintend - fingerprintstart) + 4; + buf = malloc(totallen); + if (buf == NULL) goto memerr; + + bufp = buf; + lenp = totallen; + + write_mpi(their_dh_pub, theirpublen, "Their DH pubkey"); + write_mpi(our_dh_pub, ourpublen, "Our DH pubkey"); + bufp[0] = (pubkey_type >> 8) & 0xff; + bufp[1] = pubkey_type & 0xff; + bufp += 2; lenp -= 2; + memmove(bufp, fingerprintstart, fingerprintend - fingerprintstart); + debug_data("Pubkey", bufp, fingerprintend - fingerprintstart); + bufp += fingerprintend - fingerprintstart; + lenp -= fingerprintend - fingerprintstart; + write_int(received_keyid); + debug_int("Keyid", bufp-4); + + assert(lenp == 0); + + /* Do the MAC */ + gcry_md_reset(mackey); + gcry_md_write(mackey, buf, totallen); + memmove(macbuf, gcry_md_read(mackey, GCRY_MD_SHA256), 32); + + free(buf); + buf = NULL; + + /* Verify the signature on the MAC */ + err = otrl_privkey_verify(sigbuf, siglen, pubkey_type, pubs, macbuf, 32); + if (err) goto err; + gcry_sexp_release(pubs); + pubs = NULL; + + /* Everything checked out */ + *keyidp = received_keyid; + + return err; +invval: + err = gcry_error(GPG_ERR_INV_VALUE); + goto err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + gcry_sexp_release(pubs); + return err; +} + +/* + * Create a Reveal Signature Message using the values in the given auth, + * and store it in auth->lastauthmsg. Use the given privkey to sign the + * message. + */ +static gcry_error_t create_revealsig_message(OtrlAuthInfo *auth, + OtrlPrivKey *privkey) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + unsigned char *buf = NULL, *bufp, *startmac; + size_t buflen, lenp; + + unsigned char *authbuf = NULL; + size_t authlen; + + /* Get the encrypted authenticator */ + err = calculate_pubkey_auth(&authbuf, &authlen, auth->mac_m1, auth->enc_c, + auth->our_dh.pub, auth->their_pub, privkey, auth->our_keyid); + if (err) goto err; + + buflen = OTRL_HEADER_LEN + (auth->protocol_version == 3 ? 8 : 0) + 4 + 16 + + 4 + authlen + 20; + buf = malloc(buflen); + if (buf == NULL) goto memerr; + + bufp = buf; + lenp = buflen; + + /* header */ + write_header(auth->protocol_version, '\x11'); + if (auth->protocol_version == 3) { + /* instance tags */ + write_int(auth->context->our_instance); + debug_int("Sender instag", bufp-4); + write_int(auth->context->their_instance); + debug_int("Recipient instag", bufp-4); + } + + /* r */ + write_int(16); + memmove(bufp, auth->r, 16); + debug_data("r", bufp, 16); + bufp += 16; lenp -= 16; + + /* Encrypted authenticator */ + startmac = bufp; + write_int(authlen); + memmove(bufp, authbuf, authlen); + debug_data("auth", bufp, authlen); + bufp += authlen; lenp -= authlen; + free(authbuf); + authbuf = NULL; + + /* MAC it, but only take the first 20 bytes */ + gcry_md_reset(auth->mac_m2); + gcry_md_write(auth->mac_m2, startmac, bufp - startmac); + memmove(bufp, gcry_md_read(auth->mac_m2, GCRY_MD_SHA256), 20); + debug_data("MAC", bufp, 20); + bufp += 20; lenp -= 20; + + assert(lenp == 0); + + free(auth->lastauthmsg); + auth->lastauthmsg = otrl_base64_otr_encode(buf, buflen); + if (auth->lastauthmsg == NULL) goto memerr; + free(buf); + buf = NULL; + + return err; + +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + free(authbuf); + return err; +} + +/* + * Create a Signature Message using the values in the given auth, and + * store it in auth->lastauthmsg. Use the given privkey to sign the + * message. + */ +static gcry_error_t create_signature_message(OtrlAuthInfo *auth, + OtrlPrivKey *privkey) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + unsigned char *buf = NULL, *bufp, *startmac; + size_t buflen, lenp; + + unsigned char *authbuf = NULL; + size_t authlen; + + /* Get the encrypted authenticator */ + err = calculate_pubkey_auth(&authbuf, &authlen, auth->mac_m1p, + auth->enc_cp, auth->our_dh.pub, auth->their_pub, privkey, + auth->our_keyid); + if (err) goto err; + + buflen = OTRL_HEADER_LEN + (auth->protocol_version == 3 ? 8 : 0) + 4 + + authlen + 20; + buf = malloc(buflen); + if (buf == NULL) goto memerr; + + bufp = buf; + lenp = buflen; + + /* header */ + write_header(auth->protocol_version, '\x12'); + if (auth->protocol_version == 3) { + /* instance tags */ + write_int(auth->context->our_instance); + debug_int("Sender instag", bufp-4); + write_int(auth->context->their_instance); + debug_int("Recipient instag", bufp-4); + } + + /* Encrypted authenticator */ + startmac = bufp; + write_int(authlen); + memmove(bufp, authbuf, authlen); + debug_data("auth", bufp, authlen); + bufp += authlen; lenp -= authlen; + free(authbuf); + authbuf = NULL; + + /* MAC it, but only take the first 20 bytes */ + gcry_md_reset(auth->mac_m2p); + gcry_md_write(auth->mac_m2p, startmac, bufp - startmac); + memmove(bufp, gcry_md_read(auth->mac_m2p, GCRY_MD_SHA256), 20); + debug_data("MAC", bufp, 20); + bufp += 20; lenp -= 20; + + assert(lenp == 0); + + free(auth->lastauthmsg); + auth->lastauthmsg = otrl_base64_otr_encode(buf, buflen); + if (auth->lastauthmsg == NULL) goto memerr; + free(buf); + buf = NULL; + + return err; + +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + free(authbuf); + return err; +} + +/* + * Handle an incoming D-H Key Message. If no error is returned, and + * *havemsgp is 1, the message to sent will be left in auth->lastauthmsg. + * Use the given private authentication key to sign messages. + */ +gcry_error_t otrl_auth_handle_key(OtrlAuthInfo *auth, const char *keymsg, + int *havemsgp, OtrlPrivKey *privkey) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + unsigned char *buf = NULL, *bufp = NULL; + size_t buflen, lenp; + gcry_mpi_t incoming_pub = NULL; + int res; + unsigned int msg_version; + + *havemsgp = 0; + + msg_version = otrl_proto_message_version(keymsg); + + res = otrl_base64_otr_decode(keymsg, &buf, &buflen); + if (res == -1) goto memerr; + if (res == -2) goto invval; + + bufp = buf; + lenp = buflen; + + /* Header */ + skip_header('\x0a'); + + if (msg_version == 3) { + require_len(8); + bufp += 8; lenp -= 8; + } + + /* g^y */ + read_mpi(incoming_pub); + + if (lenp != 0) goto invval; + free(buf); + buf = NULL; + + switch(auth->authstate) { + case OTRL_AUTHSTATE_AWAITING_DHKEY: + /* The other party may also be establishing a session with + another instance running a different version. Ignore any + DHKEY messages we aren't expecting. */ + if (msg_version != auth->protocol_version) { + goto err; + } + + /* Store the incoming public key */ + gcry_mpi_release(auth->their_pub); + auth->their_pub = incoming_pub; + incoming_pub = NULL; + + /* Compute the encryption and MAC keys */ + err = otrl_dh_compute_v2_auth_keys(&(auth->our_dh), + auth->their_pub, auth->secure_session_id, + &(auth->secure_session_id_len), + &(auth->enc_c), &(auth->enc_cp), + &(auth->mac_m1), &(auth->mac_m1p), + &(auth->mac_m2), &(auth->mac_m2p)); + if (err) goto err; + + /* Create the Reveal Signature Message */ + err = create_revealsig_message(auth, privkey); + if (err) goto err; + *havemsgp = 1; + auth->authstate = OTRL_AUTHSTATE_AWAITING_SIG; + + break; + + case OTRL_AUTHSTATE_AWAITING_SIG: + if (gcry_mpi_cmp(incoming_pub, auth->their_pub) == 0) { + /* Retransmit the Reveal Signature Message */ + *havemsgp = 1; + } else { + /* Ignore this message */ + *havemsgp = 0; + } + break; + case OTRL_AUTHSTATE_NONE: + case OTRL_AUTHSTATE_AWAITING_REVEALSIG: + case OTRL_AUTHSTATE_V1_SETUP: + /* Ignore this message */ + *havemsgp = 0; + break; + } + + gcry_mpi_release(incoming_pub); + return err; + +invval: + err = gcry_error(GPG_ERR_INV_VALUE); + goto err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + gcry_mpi_release(incoming_pub); + return err; +} + +/* + * Handle an incoming Reveal Signature Message. If no error is + * returned, and *havemsgp is 1, the message to be sent will be left in + * auth->lastauthmsg. Use the given private authentication key to sign + * messages. Call the auth_succeeded callback if authentication is + * successful. + */ +gcry_error_t otrl_auth_handle_revealsig(OtrlAuthInfo *auth, + const char *revealmsg, int *havemsgp, OtrlPrivKey *privkey, + gcry_error_t (*auth_succeeded)(const OtrlAuthInfo *auth, void *asdata), + void *asdata) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + unsigned char *buf = NULL, *bufp = NULL, *gxbuf = NULL; + unsigned char *authstart, *authend, *macstart; + size_t buflen, lenp, rlen, authlen; + gcry_cipher_hd_t enc = NULL; + gcry_mpi_t incoming_pub = NULL; + unsigned char ctr[16], hashbuf[32]; + int res; + unsigned char version; + + *havemsgp = 0; + + res = otrl_base64_otr_decode(revealmsg, &buf, &buflen); + if (res == -1) goto memerr; + if (res == -2) goto invval; + + bufp = buf; + lenp = buflen; + + require_len(3); + version = bufp[1]; + + /* Header */ + skip_header('\x11'); + + if (version == 3) { + require_len(8); + bufp += 8; lenp -= 8; + } + + /* r */ + read_int(rlen); + if (rlen != 16) goto invval; + require_len(rlen); + memmove(auth->r, bufp, rlen); + bufp += rlen; lenp -= rlen; + + /* auth */ + authstart = bufp; + read_int(authlen); + require_len(authlen); + bufp += authlen; lenp -= authlen; + authend = bufp; + + /* MAC */ + require_len(20); + macstart = bufp; + bufp += 20; lenp -= 20; + + if (lenp != 0) goto invval; + + switch(auth->authstate) { + case OTRL_AUTHSTATE_AWAITING_REVEALSIG: + gxbuf = malloc(auth->encgx_len); + if (auth->encgx_len && gxbuf == NULL) goto memerr; + + /* Use r to decrypt the value of g^x we received earlier */ + err = gcry_cipher_open(&enc, GCRY_CIPHER_AES, GCRY_CIPHER_MODE_CTR, + GCRY_CIPHER_SECURE); + if (err) goto err; + + err = gcry_cipher_setkey(enc, auth->r, 16); + if (err) goto err; + + memset(ctr, 0, 16); + err = gcry_cipher_setctr(enc, ctr, 16); + if (err) goto err; + + err = gcry_cipher_decrypt(enc, gxbuf, auth->encgx_len, + auth->encgx, auth->encgx_len); + if (err) goto err; + + gcry_cipher_close(enc); + enc = NULL; + + /* Check the hash */ + gcry_md_hash_buffer(GCRY_MD_SHA256, hashbuf, gxbuf, + auth->encgx_len); + /* This isn't comparing secret data, but may as well use the + * constant-time version. */ + if (otrl_mem_differ(hashbuf, auth->hashgx, 32)) goto decfail; + + /* Extract g^x */ + bufp = gxbuf; + lenp = auth->encgx_len; + + read_mpi(incoming_pub); + free(gxbuf); + gxbuf = NULL; + + if (lenp != 0) goto invval; + + gcry_mpi_release(auth->their_pub); + auth->their_pub = incoming_pub; + incoming_pub = NULL; + + /* Compute the encryption and MAC keys */ + err = otrl_dh_compute_v2_auth_keys(&(auth->our_dh), + auth->their_pub, auth->secure_session_id, + &(auth->secure_session_id_len), + &(auth->enc_c), &(auth->enc_cp), + &(auth->mac_m1), &(auth->mac_m1p), + &(auth->mac_m2), &(auth->mac_m2p)); + if (err) goto err; + + /* Check the MAC */ + gcry_md_reset(auth->mac_m2); + gcry_md_write(auth->mac_m2, authstart, authend - authstart); + + if (otrl_mem_differ(macstart, + gcry_md_read(auth->mac_m2, GCRY_MD_SHA256), + 20)) goto invval; + + /* Check the auth */ + err = check_pubkey_auth(auth->their_fingerprint, + &(auth->their_keyid), authstart + 4, + authend - authstart - 4, auth->mac_m1, auth->enc_c, + auth->our_dh.pub, auth->their_pub); + if (err) goto err; + + authstart = NULL; + authend = NULL; + macstart = NULL; + free(buf); + buf = NULL; + + /* Create the Signature Message */ + err = create_signature_message(auth, privkey); + if (err) goto err; + + /* No error? Then we've completed our end of the + * authentication. */ + auth->session_id_half = OTRL_SESSIONID_SECOND_HALF_BOLD; + if (auth_succeeded) err = auth_succeeded(auth, asdata); + *havemsgp = 1; + auth->our_keyid = 0; + auth->authstate = OTRL_AUTHSTATE_NONE; + + break; + case OTRL_AUTHSTATE_NONE: + case OTRL_AUTHSTATE_AWAITING_DHKEY: + case OTRL_AUTHSTATE_AWAITING_SIG: + case OTRL_AUTHSTATE_V1_SETUP: + /* Ignore this message */ + *havemsgp = 0; + free(buf); + buf = NULL; + break; + } + + return err; + +decfail: + err = gcry_error(GPG_ERR_NO_ERROR); + goto err; +invval: + err = gcry_error(GPG_ERR_INV_VALUE); + goto err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + free(gxbuf); + gcry_cipher_close(enc); + gcry_mpi_release(incoming_pub); + return err; +} + +/* + * Handle an incoming Signature Message. If no error is returned, and + * *havemsgp is 1, the message to be sent will be left in + * auth->lastauthmsg. Call the auth_succeeded callback if + * authentication is successful. + */ +gcry_error_t otrl_auth_handle_signature(OtrlAuthInfo *auth, + const char *sigmsg, int *havemsgp, + gcry_error_t (*auth_succeeded)(const OtrlAuthInfo *auth, void *asdata), + void *asdata) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + unsigned char *buf = NULL, *bufp = NULL; + unsigned char *authstart, *authend, *macstart; + size_t buflen, lenp, authlen; + int res; + unsigned char version; + + *havemsgp = 0; + + res = otrl_base64_otr_decode(sigmsg, &buf, &buflen); + if (res == -1) goto memerr; + if (res == -2) goto invval; + + bufp = buf; + lenp = buflen; + + require_len(3); + version = bufp[1]; + + /* Header */ + skip_header('\x12'); + + if (version == 3) { + require_len(8); + bufp += 8; lenp -= 8; + } + + /* auth */ + authstart = bufp; + read_int(authlen); + require_len(authlen); + bufp += authlen; lenp -= authlen; + authend = bufp; + + /* MAC */ + require_len(20); + macstart = bufp; + bufp += 20; lenp -= 20; + + if (lenp != 0) goto invval; + + switch(auth->authstate) { + case OTRL_AUTHSTATE_AWAITING_SIG: + /* Check the MAC */ + gcry_md_reset(auth->mac_m2p); + gcry_md_write(auth->mac_m2p, authstart, authend - authstart); + if (otrl_mem_differ(macstart, + gcry_md_read(auth->mac_m2p, GCRY_MD_SHA256), + 20)) goto invval; + + /* Check the auth */ + err = check_pubkey_auth(auth->their_fingerprint, + &(auth->their_keyid), authstart + 4, + authend - authstart - 4, auth->mac_m1p, auth->enc_cp, + auth->our_dh.pub, auth->their_pub); + if (err) goto err; + + authstart = NULL; + authend = NULL; + macstart = NULL; + free(buf); + buf = NULL; + + /* No error? Then we've completed our end of the + * authentication. */ + auth->session_id_half = OTRL_SESSIONID_FIRST_HALF_BOLD; + if (auth_succeeded) err = auth_succeeded(auth, asdata); + free(auth->lastauthmsg); + auth->lastauthmsg = NULL; + *havemsgp = 0; + auth->our_keyid = 0; + auth->authstate = OTRL_AUTHSTATE_NONE; + + break; + case OTRL_AUTHSTATE_NONE: + case OTRL_AUTHSTATE_AWAITING_DHKEY: + case OTRL_AUTHSTATE_AWAITING_REVEALSIG: + case OTRL_AUTHSTATE_V1_SETUP: + /* Ignore this message */ + *havemsgp = 0; + free(buf); + buf = NULL; + break; + } + + return err; + +invval: + err = gcry_error(GPG_ERR_INV_VALUE); + goto err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + return err; +} + +/* Version 1 routines, for compatibility */ + +/* + * Create a verion 1 Key Exchange Message using the values in the given + * auth, and store it in auth->lastauthmsg. Set the Reply field to the + * given value, and use the given privkey to sign the message. + */ +static gcry_error_t create_v1_key_exchange_message(OtrlAuthInfo *auth, + unsigned char reply, OtrlPrivKey *privkey) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + const enum gcry_mpi_format format = GCRYMPI_FMT_USG; + unsigned char *buf = NULL, *bufp = NULL, *sigbuf = NULL; + size_t lenp, ourpublen, totallen, siglen; + unsigned char hashbuf[20]; + + if (privkey->pubkey_type != OTRL_PUBKEY_TYPE_DSA) { + return gpg_error(GPG_ERR_INV_VALUE); + } + + /* How big is the DH public key? */ + gcry_mpi_print(format, NULL, 0, &ourpublen, auth->our_dh.pub); + + totallen = 3 + 1 + privkey->pubkey_datalen + 4 + 4 + ourpublen + 40; + buf = malloc(totallen); + if (buf == NULL) goto memerr; + + bufp = buf; + lenp = totallen; + + memmove(bufp, "\x00\x01\x0a", 3); /* header */ + debug_data("Header", bufp, 3); + bufp += 3; lenp -= 3; + + bufp[0] = reply; + debug_data("Reply", bufp, 1); + bufp += 1; lenp -= 1; + + memmove(bufp, privkey->pubkey_data, privkey->pubkey_datalen); + debug_data("Pubkey", bufp, privkey->pubkey_datalen); + bufp += privkey->pubkey_datalen; lenp -= privkey->pubkey_datalen; + + write_int(auth->our_keyid); + debug_int("Keyid", bufp-4); + + write_mpi(auth->our_dh.pub, ourpublen, "D-H y"); + + /* Hash all the data written so far, and sign the hash */ + gcry_md_hash_buffer(GCRY_MD_SHA1, hashbuf, buf, bufp - buf); + + err = otrl_privkey_sign(&sigbuf, &siglen, privkey, hashbuf, 20); + if (err) goto err; + + if (siglen != 40) goto invval; + memmove(bufp, sigbuf, 40); + debug_data("Signature", bufp, 40); + bufp += 40; lenp -= 40; + free(sigbuf); + sigbuf = NULL; + + assert(lenp == 0); + + free(auth->lastauthmsg); + auth->lastauthmsg = otrl_base64_otr_encode(buf, totallen); + if (auth->lastauthmsg == NULL) goto memerr; + free(buf); + buf = NULL; + + return err; + +invval: + err = gcry_error(GPG_ERR_INV_VALUE); + goto err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + free(sigbuf); + return err; +} + +/* + * Start a fresh AKE (version 1) using the given OtrlAuthInfo. If + * our_dh is NULL, generate a fresh DH keypair to use. Otherwise, use a + * copy of the one passed (with the given keyid). Use the given private + * key to sign the message. If no error is returned, the message to + * transmit will be contained in auth->lastauthmsg. + */ +gcry_error_t otrl_auth_start_v1(OtrlAuthInfo *auth, DH_keypair *our_dh, + unsigned int our_keyid, OtrlPrivKey *privkey) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + + /* Clear out this OtrlAuthInfo and start over */ + otrl_auth_clear(auth); + auth->initiated = 1; + auth->protocol_version = 1; + + /* Import the given DH keypair, or else create a fresh one */ + if (our_dh) { + otrl_dh_keypair_copy(&(auth->our_dh), our_dh); + auth->our_keyid = our_keyid; + } else { + otrl_dh_gen_keypair(DH1536_GROUP_ID, &(auth->our_dh)); + auth->our_keyid = 1; + } + + err = create_v1_key_exchange_message(auth, 0, privkey); + if (!err) { + auth->authstate = OTRL_AUTHSTATE_V1_SETUP; + } + + return err; +} + +/* + * Handle an incoming v1 Key Exchange Message. If no error is returned, + * and *havemsgp is 1, the message to be sent will be left in + * auth->lastauthmsg. Use the given private authentication key to sign + * messages. Call the auth_secceeded callback if authentication is + * successful. If non-NULL, use a copy of the given D-H keypair, with + * the given keyid. + */ +gcry_error_t otrl_auth_handle_v1_key_exchange(OtrlAuthInfo *auth, + const char *keyexchmsg, int *havemsgp, OtrlPrivKey *privkey, + DH_keypair *our_dh, unsigned int our_keyid, + gcry_error_t (*auth_succeeded)(const OtrlAuthInfo *auth, void *asdata), + void *asdata) +{ + gcry_error_t err = gcry_error(GPG_ERR_NO_ERROR); + unsigned char *buf = NULL, *bufp = NULL; + unsigned char *fingerprintstart, *fingerprintend; + unsigned char fingerprintbuf[20], hashbuf[20]; + gcry_mpi_t p, q, g, y, received_pub = NULL; + gcry_sexp_t pubs = NULL; + size_t buflen, lenp; + unsigned char received_reply; + unsigned int received_keyid; + int res; + + *havemsgp = 0; + + res = otrl_base64_otr_decode(keyexchmsg, &buf, &buflen); + if (res == -1) goto memerr; + if (res == -2) goto invval; + + bufp = buf; + lenp = buflen; + + /* Header */ + require_len(3); + if (memcmp(bufp, "\x00\x01\x0a", 3)) goto invval; + bufp += 3; lenp -= 3; + + /* Reply */ + require_len(1); + received_reply = bufp[0]; + bufp += 1; lenp -= 1; + + /* Public Key */ + fingerprintstart = bufp; + read_mpi(p); + read_mpi(q); + read_mpi(g); + read_mpi(y); + fingerprintend = bufp; + gcry_md_hash_buffer(GCRY_MD_SHA1, fingerprintbuf, + fingerprintstart, fingerprintend-fingerprintstart); + gcry_sexp_build(&pubs, NULL, + "(public-key (dsa (p %m)(q %m)(g %m)(y %m)))", p, q, g, y); + gcry_mpi_release(p); + gcry_mpi_release(q); + gcry_mpi_release(g); + gcry_mpi_release(y); + + /* keyid */ + read_int(received_keyid); + if (received_keyid == 0) goto invval; + + /* D-H pubkey */ + read_mpi(received_pub); + + /* Verify the signature */ + if (lenp != 40) goto invval; + gcry_md_hash_buffer(GCRY_MD_SHA1, hashbuf, buf, bufp - buf); + err = otrl_privkey_verify(bufp, lenp, OTRL_PUBKEY_TYPE_DSA, + pubs, hashbuf, 20); + if (err) goto err; + gcry_sexp_release(pubs); + pubs = NULL; + free(buf); + buf = NULL; + + if (auth->authstate != OTRL_AUTHSTATE_V1_SETUP && received_reply == 0x01) { + /* They're replying to something we never sent. We must be + * logged in more than once; ignore the message. */ + err = gpg_error(GPG_ERR_NO_ERROR); + goto err; + } + + if (auth->authstate != OTRL_AUTHSTATE_V1_SETUP) { + /* Clear the auth and start over */ + otrl_auth_clear(auth); + } + + /* Everything checked out */ + auth->their_keyid = received_keyid; + gcry_mpi_release(auth->their_pub); + auth->their_pub = received_pub; + received_pub = NULL; + memmove(auth->their_fingerprint, fingerprintbuf, 20); + + if (received_reply == 0x01) { + /* Don't send a reply to this. */ + *havemsgp = 0; + } else { + /* Import the given DH keypair, or else create a fresh one */ + if (our_dh) { + otrl_dh_keypair_copy(&(auth->our_dh), our_dh); + auth->our_keyid = our_keyid; + } else if (auth->our_keyid == 0) { + otrl_dh_gen_keypair(DH1536_GROUP_ID, &(auth->our_dh)); + auth->our_keyid = 1; + } + + /* Reply with our own Key Exchange Message */ + err = create_v1_key_exchange_message(auth, 1, privkey); + if (err) goto err; + *havemsgp = 1; + } + + /* Compute the session id */ + err = otrl_dh_compute_v1_session_id(&(auth->our_dh), + auth->their_pub, auth->secure_session_id, + &(auth->secure_session_id_len), + &(auth->session_id_half)); + if (err) goto err; + + /* We've completed our end of the authentication */ + auth->protocol_version = 1; + if (auth_succeeded) err = auth_succeeded(auth, asdata); + auth->our_keyid = 0; + auth->authstate = OTRL_AUTHSTATE_NONE; + + return err; + +invval: + err = gcry_error(GPG_ERR_INV_VALUE); + goto err; +memerr: + err = gcry_error(GPG_ERR_ENOMEM); +err: + free(buf); + gcry_sexp_release(pubs); + gcry_mpi_release(received_pub); + return err; +} + +/* + * Copy relevant information from the master OtrlAuthInfo to an + * instance OtrlAuthInfo in response to a D-H Key with a new + * instance. The fields copied will depend on the state of the + * master auth. + */ +void otrl_auth_copy_on_key(OtrlAuthInfo *m_auth, OtrlAuthInfo *auth) +{ + switch(m_auth->authstate) { + case OTRL_AUTHSTATE_AWAITING_DHKEY: + case OTRL_AUTHSTATE_AWAITING_SIG: + /* Copy our D-H Commit information to the new instance */ + otrl_dh_keypair_free(&(auth->our_dh)); + auth->initiated = m_auth->initiated; + otrl_dh_keypair_copy(&(auth->our_dh), &(m_auth->our_dh)); + auth->our_keyid = m_auth->our_keyid; + memmove(auth->r, m_auth->r, 16); + if (auth->encgx) free(auth->encgx); + auth->encgx = malloc(m_auth->encgx_len); + memmove(auth->encgx, m_auth->encgx, m_auth->encgx_len); + memmove(auth->hashgx, m_auth->hashgx, 32); + + auth->authstate = OTRL_AUTHSTATE_AWAITING_DHKEY; + break; + + default: + /* This bad state will be detected and handled later */ + break; + } +} + +#ifdef OTRL_TESTING_AUTH +#include "mem.h" +#include "privkey.h" + +#define CHECK_ERR if (err) { printf("Error: %s\n", gcry_strerror(err)); \ + return 1; } + +static gcry_error_t starting(const OtrlAuthInfo *auth, void *asdata) +{ + char *name = asdata; + + fprintf(stderr, "\nStarting ENCRYPTED mode for %s (v%d).\n", + name, auth->protocol_version); + + fprintf(stderr, "\nour_dh (%d):", auth->our_keyid); + gcry_mpi_dump(auth->our_dh.pub); + fprintf(stderr, "\ntheir_pub (%d):", auth->their_keyid); + gcry_mpi_dump(auth->their_pub); + + debug_data("\nTheir fingerprint", auth->their_fingerprint, 20); + debug_data("\nSecure session id", auth->secure_session_id, + auth->secure_session_id_len); + fprintf(stderr, "Sessionid half: %d\n\n", auth->session_id_half); + + return gpg_error(GPG_ERR_NO_ERROR); +} + +int main(int argc, char **argv) +{ + OtrlAuthInfo alice, bob; + gcry_error_t err; + int havemsg; + OtrlUserState us; + OtrlPrivKey *alicepriv, *bobpriv; + + otrl_mem_init(); + otrl_dh_init(); + otrl_auth_new(&alice); + otrl_auth_new(&bob); + + us = otrl_userstate_create(); + otrl_privkey_read(us, "/home/iang/.gaim/otr.private_key"); + alicepriv = otrl_privkey_find(us, "oneeyedian", "prpl-oscar"); + bobpriv = otrl_privkey_find(us, "otr4ian", "prpl-oscar"); + + printf("\n\n ***** V2 *****\n\n"); + + err = otrl_auth_start_v23(&bob, NULL, 0); + CHECK_ERR + printf("\nBob: %d\n%s\n\n", strlen(bob.lastauthmsg), bob.lastauthmsg); + err = otrl_auth_handle_commit(&alice, bob.lastauthmsg, NULL, 0); + CHECK_ERR + printf("\nAlice: %d\n%s\n\n", strlen(alice.lastauthmsg), alice.lastauthmsg); + err = otrl_auth_handle_key(&bob, alice.lastauthmsg, &havemsg, bobpriv); + CHECK_ERR + if (havemsg) { + printf("\nBob: %d\n%s\n\n", strlen(bob.lastauthmsg), bob.lastauthmsg); + } else { + printf("\nIGNORE\n\n"); + } + err = otrl_auth_handle_revealsig(&alice, bob.lastauthmsg, &havemsg, + alicepriv, starting, "Alice"); + CHECK_ERR + if (havemsg) { + printf("\nAlice: %d\n%s\n\n", strlen(alice.lastauthmsg), + alice.lastauthmsg); + } else { + printf("\nIGNORE\n\n"); + } + err = otrl_auth_handle_signature(&bob, alice.lastauthmsg, &havemsg, + starting, "Bob"); + CHECK_ERR + + printf("\n\n ***** V1 *****\n\n"); + + err = otrl_auth_start_v1(&bob, NULL, 0, bobpriv); + CHECK_ERR + printf("\nBob: %d\n%s\n\n", strlen(bob.lastauthmsg), bob.lastauthmsg); + err = otrl_auth_handle_v1_key_exchange(&alice, bob.lastauthmsg, + &havemsg, alicepriv, NULL, 0, starting, "Alice"); + CHECK_ERR + if (havemsg) { + printf("\nAlice: %d\n%s\n\n", strlen(alice.lastauthmsg), + alice.lastauthmsg); + } else { + printf("\nIGNORE\n\n"); + } + err = otrl_auth_handle_v1_key_exchange(&bob, alice.lastauthmsg, + &havemsg, bobpriv, NULL, 0, starting, "Bob"); + CHECK_ERR + if (havemsg) { + printf("\nBob: %d\n%s\n\n", strlen(bob.lastauthmsg), bob.lastauthmsg); + } else { + printf("\nIGNORE\n\n"); + } + + otrl_userstate_free(us); + otrl_auth_clear(&alice); + otrl_auth_clear(&bob); + return 0; +} +#endif |