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- Committer: Package Import Robot
- Author(s): Dmitrijs Ledkovs
- Date: 2012-11-05 01:06:26 UTC
- Revision ID: package-import@ubuntu.com-20121105010626-4m3hldpaz3jfr3wb
Tags: upstream-3.2.1
Import upstream version 3.2.1
- files added:
- packaging
- packaging/CVS
- packaging/fedora
- packaging/fedora/CVS
- src
- toolkit
added
removed
src/context.c
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/*
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* Off-the-Record Messaging library
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* Copyright (C) 2004-2008 Ian Goldberg, Chris Alexander, Nikita Borisov
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* <otr@cypherpunks.ca>
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of version 2.1 of the GNU Lesser General
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* Public License as published by the Free Software Foundation.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/* system headers */
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#include <stdlib.h>
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#include <assert.h>
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/* libgcrypt headers */
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#include <gcrypt.h>
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/* libotr headers */
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#include "context.h"
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/* Create a new connection context. */
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static ConnContext * new_context(const char * user, const char * accountname,
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const char * protocol)
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{
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ConnContext * context;
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OtrlSMState *smstate;
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context = malloc(sizeof(*context));
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assert(context != NULL);
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context->username = strdup(user);
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context->accountname = strdup(accountname);
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context->protocol = strdup(protocol);
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context->fragment = NULL;
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context->fragment_len = 0;
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context->fragment_n = 0;
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context->fragment_k = 0;
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context->msgstate = OTRL_MSGSTATE_PLAINTEXT;
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otrl_auth_new(&(context->auth));
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smstate = malloc(sizeof(OtrlSMState));
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assert(smstate != NULL);
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otrl_sm_state_new(smstate);
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context->smstate = smstate;
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context->fingerprint_root.fingerprint = NULL;
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context->fingerprint_root.context = context;
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context->fingerprint_root.next = NULL;
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context->fingerprint_root.tous = NULL;
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context->active_fingerprint = NULL;
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context->their_keyid = 0;
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context->their_y = NULL;
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context->their_old_y = NULL;
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context->our_keyid = 0;
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context->our_dh_key.groupid = 0;
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context->our_dh_key.priv = NULL;
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context->our_dh_key.pub = NULL;
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context->our_old_dh_key.groupid = 0;
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context->our_old_dh_key.priv = NULL;
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context->our_old_dh_key.pub = NULL;
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otrl_dh_session_blank(&(context->sesskeys[0][0]));
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otrl_dh_session_blank(&(context->sesskeys[0][1]));
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otrl_dh_session_blank(&(context->sesskeys[1][0]));
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otrl_dh_session_blank(&(context->sesskeys[1][1]));
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memset(context->sessionid, 0, 20);
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context->sessionid_len = 0;
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context->protocol_version = 0;
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context->numsavedkeys = 0;
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context->preshared_secret = NULL;
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context->preshared_secret_len = 0;
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context->saved_mac_keys = NULL;
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context->generation = 0;
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context->lastsent = 0;
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context->lastmessage = NULL;
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context->may_retransmit = 0;
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context->otr_offer = OFFER_NOT;
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context->app_data = NULL;
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context->app_data_free = NULL;
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context->next = NULL;
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return context;
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}
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/* Look up a connection context by name/account/protocol from the given
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* OtrlUserState. If add_if_missing is true, allocate and return a new
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* context if one does not currently exist. In that event, call
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* add_app_data(data, context) so that app_data and app_data_free can be
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* filled in by the application, and set *addedp to 1. */
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ConnContext * otrl_context_find(OtrlUserState us, const char *user,
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const char *accountname, const char *protocol, int add_if_missing,
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int *addedp,
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void (*add_app_data)(void *data, ConnContext *context), void *data)
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{
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ConnContext ** curp;
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int usercmp = 1, acctcmp = 1, protocmp = 1;
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if (addedp) *addedp = 0;
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if (!user || !accountname || !protocol) return NULL;
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for (curp = &(us->context_root); *curp; curp = &((*curp)->next)) {
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if ((usercmp = strcmp((*curp)->username, user)) > 0 ||
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(usercmp == 0 &&
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(acctcmp = strcmp((*curp)->accountname, accountname)) > 0) ||
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(usercmp == 0 && acctcmp == 0 &&
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(protocmp = strcmp((*curp)->protocol, protocol)) >= 0))
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/* We're at the right place in the list. We've either found
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* it, or gone too far. */
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break;
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}
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if (usercmp == 0 && acctcmp == 0 && protocmp == 0) {
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/* Found it! */
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return *curp;
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}
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if (add_if_missing) {
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ConnContext *newctx;
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if (addedp) *addedp = 1;
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newctx = new_context(user, accountname, protocol);
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newctx->next = *curp;
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if (*curp) {
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(*curp)->tous = &(newctx->next);
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}
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*curp = newctx;
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newctx->tous = curp;
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if (add_app_data) {
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add_app_data(data, *curp);
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}
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return *curp;
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}
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return NULL;
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}
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/* Find a fingerprint in a given context, perhaps adding it if not
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* present. */
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Fingerprint *otrl_context_find_fingerprint(ConnContext *context,
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unsigned char fingerprint[20], int add_if_missing, int *addedp)
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{
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Fingerprint *f = context->fingerprint_root.next;
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if (addedp) *addedp = 0;
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while(f) {
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if (!memcmp(f->fingerprint, fingerprint, 20)) return f;
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f = f->next;
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}
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/* Didn't find it. */
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if (add_if_missing) {
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if (addedp) *addedp = 1;
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f = malloc(sizeof(*f));
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assert(f != NULL);
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f->fingerprint = malloc(20);
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assert(f->fingerprint != NULL);
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memmove(f->fingerprint, fingerprint, 20);
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f->context = context;
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f->trust = NULL;
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f->next = context->fingerprint_root.next;
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if (f->next) {
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f->next->tous = &(f->next);
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}
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context->fingerprint_root.next = f;
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f->tous = &(context->fingerprint_root.next);
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return f;
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}
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return NULL;
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}
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/* Set the trust level for a given fingerprint */
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void otrl_context_set_trust(Fingerprint *fprint, const char *trust)
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{
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if (fprint == NULL) return;
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free(fprint->trust);
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fprint->trust = trust ? strdup(trust) : NULL;
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}
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/* Set the preshared secret for a given fingerprint. Note that this
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* currently only stores the secret in the ConnContext structure, but
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* doesn't yet do anything with it. */
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void otrl_context_set_preshared_secret(ConnContext *context,
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const unsigned char *secret, size_t secret_len)
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{
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free(context->preshared_secret);
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context->preshared_secret = NULL;
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context->preshared_secret_len = 0;
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if (secret_len) {
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context->preshared_secret = malloc(secret_len);
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if (context->preshared_secret) {
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memmove(context->preshared_secret, secret, secret_len);
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context->preshared_secret_len = secret_len;
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}
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}
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}
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/* Force a context into the OTRL_MSGSTATE_FINISHED state. */
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void otrl_context_force_finished(ConnContext *context)
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{
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context->msgstate = OTRL_MSGSTATE_FINISHED;
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otrl_auth_clear(&(context->auth));
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free(context->fragment);
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context->fragment = NULL;
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context->fragment_len = 0;
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context->fragment_n = 0;
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context->fragment_k = 0;
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context->active_fingerprint = NULL;
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context->their_keyid = 0;
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gcry_mpi_release(context->their_y);
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context->their_y = NULL;
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gcry_mpi_release(context->their_old_y);
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context->their_old_y = NULL;
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context->our_keyid = 0;
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otrl_dh_keypair_free(&(context->our_dh_key));
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otrl_dh_keypair_free(&(context->our_old_dh_key));
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otrl_dh_session_free(&(context->sesskeys[0][0]));
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otrl_dh_session_free(&(context->sesskeys[0][1]));
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otrl_dh_session_free(&(context->sesskeys[1][0]));
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otrl_dh_session_free(&(context->sesskeys[1][1]));
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memset(context->sessionid, 0, 20);
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context->sessionid_len = 0;
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free(context->preshared_secret);
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context->preshared_secret = NULL;
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context->preshared_secret_len = 0;
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context->protocol_version = 0;
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context->numsavedkeys = 0;
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free(context->saved_mac_keys);
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context->saved_mac_keys = NULL;
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gcry_free(context->lastmessage);
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context->lastmessage = NULL;
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context->may_retransmit = 0;
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otrl_sm_state_free(context->smstate);
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}
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/* Force a context into the OTRL_MSGSTATE_PLAINTEXT state. */
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void otrl_context_force_plaintext(ConnContext *context)
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{
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/* First clean up everything we'd need to do for the FINISHED state */
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otrl_context_force_finished(context);
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/* And just set the state properly */
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context->msgstate = OTRL_MSGSTATE_PLAINTEXT;
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}
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/* Forget a fingerprint (so long as it's not the active one. If it's a
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* fingerprint_root, forget the whole context (as long as
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* and_maybe_context is set, and it's PLAINTEXT). Also, if it's not
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* the fingerprint_root, but it's the only fingerprint, and we're
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* PLAINTEXT, forget the whole context if and_maybe_context is set. */
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void otrl_context_forget_fingerprint(Fingerprint *fprint,
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int and_maybe_context)
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{
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ConnContext *context = fprint->context;
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if (fprint == &(context->fingerprint_root)) {
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if (context->msgstate == OTRL_MSGSTATE_PLAINTEXT &&
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and_maybe_context) {
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otrl_context_forget(context);
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}
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} else {
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if (context->msgstate != OTRL_MSGSTATE_PLAINTEXT ||
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context->active_fingerprint != fprint) {
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free(fprint->fingerprint);
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free(fprint->trust);
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*(fprint->tous) = fprint->next;
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if (fprint->next) {
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fprint->next->tous = fprint->tous;
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}
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free(fprint);
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if (context->msgstate == OTRL_MSGSTATE_PLAINTEXT &&
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context->fingerprint_root.next == NULL &&
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and_maybe_context) {
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/* We just deleted the only fingerprint. Forget the
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* whole thing. */
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otrl_context_forget(context);
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}
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}
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}
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}
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/* Forget a whole context, so long as it's PLAINTEXT. */
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void otrl_context_forget(ConnContext *context)
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{
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if (context->msgstate != OTRL_MSGSTATE_PLAINTEXT) return;
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/* Just to be safe, force to plaintext. This also frees any
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* extraneous data lying around. */
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otrl_context_force_plaintext(context);
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/* First free all the Fingerprints */
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while(context->fingerprint_root.next) {
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otrl_context_forget_fingerprint(context->fingerprint_root.next, 0);
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}
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/* Now free all the dynamic info here */
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free(context->username);
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free(context->accountname);
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free(context->protocol);
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free(context->smstate);
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context->username = NULL;
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context->accountname = NULL;
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context->protocol = NULL;
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context->smstate = NULL;
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/* Free the application data, if it exists */
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if (context->app_data && context->app_data_free) {
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(context->app_data_free)(context->app_data);
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context->app_data = NULL;
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}
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/* Fix the list linkages */
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*(context->tous) = context->next;
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if (context->next) {
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context->next->tous = context->tous;
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}
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free(context);
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}
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/* Forget all the contexts in a given OtrlUserState. */
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void otrl_context_forget_all(OtrlUserState us)
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{
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while (us->context_root) {
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otrl_context_force_plaintext(us->context_root);
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otrl_context_forget(us->context_root);
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}
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}
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