--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mcabber/mcabber/otr.c	Mon Jan 18 15:36:19 2010 +0200
@@ -0,0 +1,777 @@
+/*
+ * otr.c        -- Off-The-Record Messaging for mcabber
+ *
+ * Copyright (C) 2007-2009 Frank Zschockelt <mcabber_otr@freakysoft.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA
+ */
+
+#include <config.h>
+#include <glib.h>
+
+#ifdef HAVE_LIBOTR
+
+#include "hbuf.h"
+#include "logprint.h"
+#include "nohtml.h"
+#include "otr.h"
+#include "roster.h"
+#include "screen.h"
+#include "settings.h"
+#include "utils.h"
+#include "xmpp.h"
+
+#define OTR_PROTOCOL_NAME "jabber"
+
+static OtrlUserState userstate = NULL;
+static char *account = NULL;
+static char *keyfile = NULL;
+static char *fprfile = NULL;
+
+static int otr_is_enabled = FALSE;
+
+static OtrlPolicy cb_policy             (void *opdata, ConnContext *ctx);
+static void       cb_create_privkey     (void *opdata,
+                                         const char *accountname,
+                                         const char *protocol);
+static int        cb_is_logged_in       (void *opdata,
+                                         const char *accountname,
+                                         const char *protocol,
+                                         const char *recipient);
+static void       cb_inject_message     (void *opdata,
+                                         const char *accountname,
+                                         const char *protocol,
+                                         const char *recipient,
+                                         const char *message);
+static void       cb_notify             (void *opdata,
+                                         OtrlNotifyLevel level,
+                                         const char *accountname,
+                                         const char *protocol,
+                                         const char *username,
+                                         const char *title,
+                                         const char *primary,
+                                         const char *secondary);
+static int        cb_display_otr_message(void *opdata,
+                                         const char *accountname,
+                                         const char *protocol,
+                                         const char *username,
+                                         const char *msg);
+static void       cb_update_context_list(void *opdata);
+static const char *cb_protocol_name     (void *opdata, const char *protocol);
+static void       cb_protocol_name_free (void *opdata,
+                                         const char *protocol_name);
+static void       cb_new_fingerprint    (void *opdata, OtrlUserState us,
+                                         const char *accountname,
+                                         const char *protocol,
+                                         const char *username,
+                                         unsigned char fingerprint[20]);
+static void       cb_write_fingerprints (void *opdata);
+static void       cb_gone_secure        (void *opdata, ConnContext *context);
+static void       cb_gone_insecure      (void *opdata, ConnContext *context);
+static void       cb_still_secure       (void *opdata, ConnContext *context,
+                                         int is_reply);
+static void       cb_log_message        (void *opdata, const char *message);
+static int        cb_max_message_size   (void *opdata, ConnContext *context);
+
+static OtrlMessageAppOps ops =
+{
+  cb_policy,
+  cb_create_privkey,
+  cb_is_logged_in,
+  cb_inject_message,
+  cb_notify,
+  cb_display_otr_message,
+  cb_update_context_list,
+  cb_protocol_name,
+  cb_protocol_name_free,
+  cb_new_fingerprint,
+  cb_write_fingerprints,
+  cb_gone_secure,
+  cb_gone_insecure,
+  cb_still_secure,
+  cb_log_message,
+  cb_max_message_size,
+  NULL, /*account_name*/
+  NULL  /*account_name_free*/
+};
+
+static void otr_message_disconnect(ConnContext *ctx);
+static ConnContext *otr_get_context(const char *buddy);
+static void otr_startstop(const char *buddy, int start);
+static void otr_handle_smp_tlvs(OtrlTLV *tlvs, ConnContext *ctx);
+
+static char *otr_get_dir(void);
+
+void otr_init(const char *fjid)
+{
+  char *root;
+
+  if (userstate) //already initialised
+    return;
+
+  otr_is_enabled = !!settings_opt_get_int("otr");
+
+  if (!otr_is_enabled)
+    return;
+
+  OTRL_INIT;
+
+  userstate = otrl_userstate_create();
+
+  root = otr_get_dir();
+  account = jidtodisp(fjid);
+  keyfile = g_strdup_printf("%s%s.key", root, account);
+  fprfile = g_strdup_printf("%s%s.fpr", root, account);
+  g_free(root);
+
+  if (otrl_privkey_read(userstate, keyfile)){
+    scr_LogPrint(LPRINT_LOGNORM, "Could not read OTR key from %s", keyfile);
+    cb_create_privkey(NULL, account, OTR_PROTOCOL_NAME);
+  }
+  if (otrl_privkey_read_fingerprints(userstate, fprfile, NULL, NULL)){
+    scr_LogPrint(LPRINT_LOGNORM, "Could not read OTR fingerprints from %s",
+                 fprfile);
+  }
+}
+
+void otr_terminate(void)
+{
+  ConnContext *ctx;
+
+  if (!otr_is_enabled)
+    return;
+
+  for (ctx = userstate->context_root; ctx; ctx = ctx->next)
+    if (ctx->msgstate == OTRL_MSGSTATE_ENCRYPTED)
+      otr_message_disconnect(ctx);
+
+  g_free(account);
+  account = NULL;
+
+  /* XXX This #ifdef is a quick workaround: when mcabber
+   * is linked to both gnutls and libotr, libgcrypt will
+   * segfault when we call otrl_userstate_free().
+   * This is reported to be a bug in libgcrypt :-/
+   * Mikael
+   */
+#if defined(HAVE_GNUTLS) && !defined(HAVE_OPENSSL) //TODO: broken now
+  if (!settings_opt_get_int("ssl"))
+#endif
+  otrl_userstate_free(userstate);
+
+  userstate = NULL;
+  g_free(keyfile);
+  keyfile = NULL;
+}
+
+static char *otr_get_dir(void)
+{
+  const char *configured_dir = settings_opt_get("otr_dir");
+
+  if (configured_dir && *configured_dir) {
+    char *xp_conf_dir;
+    int l;
+    xp_conf_dir = expand_filename(configured_dir);
+    // The path must be slash-terminated
+    l = strlen(xp_conf_dir);
+    if (xp_conf_dir[l-1] != '/') {
+      char *xp_conf_dir_tmp = xp_conf_dir;
+      xp_conf_dir = g_strdup_printf("%s/", xp_conf_dir_tmp);
+      g_free(xp_conf_dir_tmp);
+    }
+    return xp_conf_dir;
+  } else {
+    return expand_filename("~/.mcabber/otr/");
+  }
+}
+
+static ConnContext *otr_get_context(const char *buddy)
+{
+  int null = 0;
+  ConnContext *ctx;
+  char *lowcasebuddy = g_strdup(buddy);
+
+  mc_strtolower(lowcasebuddy);
+  ctx = otrl_context_find(userstate, lowcasebuddy, account, OTR_PROTOCOL_NAME,
+                          1, &null, NULL, NULL);
+  g_free(lowcasebuddy);
+  return ctx;
+}
+
+static void otr_message_disconnect(ConnContext *ctx)
+{
+  if (ctx->msgstate == OTRL_MSGSTATE_ENCRYPTED)
+    cb_gone_insecure(NULL, ctx);
+  otrl_message_disconnect(userstate, &ops, NULL, ctx->accountname,
+                          ctx->protocol, ctx->username);
+}
+
+static void otr_startstop(const char *buddy, int start)
+{
+  char *msg = NULL;
+  ConnContext *ctx = otr_get_context(buddy);
+
+  if (!userstate || !ctx)
+    return;
+
+  if (start && ctx->msgstate == OTRL_MSGSTATE_ENCRYPTED)
+    otr_message_disconnect(ctx);
+
+  if (start) {
+    OtrlPolicy policy = cb_policy(NULL, ctx);
+    if (policy == plain) {
+      scr_LogPrint(LPRINT_LOGNORM, "The OTR policy for this user is set to"
+      " plain. You have to change it first.");
+      return;
+    }
+    msg = otrl_proto_default_query_msg(ctx->accountname, policy);
+    cb_inject_message(NULL, ctx->accountname, ctx->protocol, ctx->username,
+                      msg);
+    free (msg);
+  }
+  else
+    otr_message_disconnect(ctx);
+}
+
+void otr_establish(const char *buddy)
+{
+  otr_startstop(buddy, 1);
+}
+
+void otr_disconnect(const char *buddy)
+{
+  otr_startstop(buddy, 0);
+}
+
+void otr_fingerprint(const char *buddy, const char *trust)
+{
+  char fpr[45], *tr;
+  ConnContext *ctx = otr_get_context(buddy);
+  if (!userstate || !ctx)
+    return;
+
+  if (!ctx->active_fingerprint || !ctx->active_fingerprint->fingerprint) {
+    scr_LogPrint(LPRINT_LOGNORM,
+                 "No active fingerprint - start OTR for this buddy first.");
+    return;
+  }
+
+  otrl_privkey_hash_to_human(fpr, ctx->active_fingerprint->fingerprint);
+  if (trust) {
+    if (strcmp(fpr, trust) == 0)
+      otrl_context_set_trust(ctx->active_fingerprint, "trust");
+    else
+      otrl_context_set_trust(ctx->active_fingerprint, NULL);
+  }
+
+  tr = ctx->active_fingerprint->trust;
+  scr_LogPrint(LPRINT_LOGNORM, "%s [%44s]: %s", ctx->username, fpr,
+               tr && *tr ?  "trusted" : "untrusted");
+  cb_write_fingerprints(NULL);
+}
+
+static void otr_handle_smp_tlvs(OtrlTLV *tlvs, ConnContext *ctx)
+{
+  OtrlTLV *tlv = NULL;
+  char *sbuf = NULL;
+  NextExpectedSMP nextMsg = ctx->smstate->nextExpected;
+
+  tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP1);
+  if (tlv) {
+    if (nextMsg != OTRL_SMP_EXPECT1)
+      otr_smp_abort(ctx->username);
+    else {
+      sbuf = g_strdup_printf("OTR: Received SMP Initiation. "
+                             "Answer with /otr smpr %s $secret",
+                             ctx->username);
+    }
+  }
+  tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP2);
+  if (tlv) {
+    if (nextMsg != OTRL_SMP_EXPECT2)
+      otr_smp_abort(ctx->username);
+    else {
+      sbuf = g_strdup("OTR: Received SMP Response.");
+      /* If we received TLV2, we will send TLV3 and expect TLV4 */
+      ctx->smstate->nextExpected = OTRL_SMP_EXPECT4;
+    }
+  }
+  tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP3);
+  if (tlv) {
+    if (nextMsg != OTRL_SMP_EXPECT3)
+      otr_smp_abort(ctx->username);
+    else {
+      /* If we received TLV3, we will send TLV4
+       * We will not expect more messages, so prepare for next SMP */
+      ctx->smstate->nextExpected = OTRL_SMP_EXPECT1;
+      /* Report result to user */
+      if (ctx->active_fingerprint && ctx->active_fingerprint->trust &&
+         *ctx->active_fingerprint->trust != '\0')
+        sbuf = g_strdup("OTR: SMP succeeded");
+      else
+        sbuf = g_strdup("OTR: SMP failed");
+    }
+  }
+  tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP4);
+  if (tlv) {
+    if (nextMsg != OTRL_SMP_EXPECT4)
+      otr_smp_abort(ctx->username);
+    else {
+      /* We will not expect more messages, so prepare for next SMP */
+      ctx->smstate->nextExpected = OTRL_SMP_EXPECT1;
+      /* Report result to user */
+      if (ctx->active_fingerprint && ctx->active_fingerprint->trust &&
+         *ctx->active_fingerprint->trust != '\0')
+        sbuf = g_strdup("OTR: SMP succeeded");
+      else
+        sbuf = g_strdup("OTR: SMP failed");
+    }
+  }
+  tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP_ABORT);
+  if (tlv) {
+    /* The message we are waiting for will not arrive, so reset
+     * and prepare for the next SMP */
+    sbuf = g_strdup("OTR: SMP aborted by your buddy");
+    ctx->smstate->nextExpected = OTRL_SMP_EXPECT1;
+  }
+
+  if (sbuf) {
+    scr_WriteIncomingMessage(ctx->username, sbuf, 0, HBB_PREFIX_INFO, 0);
+    g_free(sbuf);
+  }
+}
+
+/*
+ * returns whether a otr_message was received
+ * sets *otr_data to NULL, when it was an internal otr message
+ */
+int otr_receive(char **otr_data, const char *buddy, int *free_msg)
+{
+  int ignore_message;
+  char *newmessage = NULL;
+  OtrlTLV *tlvs = NULL;
+  OtrlTLV *tlv = NULL;
+  ConnContext *ctx;
+
+  ctx = otr_get_context(buddy);
+  *free_msg = 0;
+  ignore_message = otrl_message_receiving(userstate, &ops, NULL,
+                                          ctx->accountname, ctx->protocol,
+                                          ctx->username, *otr_data,
+                                          &newmessage, &tlvs,NULL, NULL);
+
+
+  tlv = otrl_tlv_find(tlvs, OTRL_TLV_DISCONNECTED);
+  if (tlv) {
+    /* Notify the user that the other side disconnected. */
+    if (ctx) {
+      cb_gone_insecure(NULL, ctx);
+      otr_disconnect(ctx->username);
+    }
+  }
+
+  otr_handle_smp_tlvs(tlvs, ctx);
+
+  if (tlvs != NULL)
+    otrl_tlv_free(tlvs);
+
+  if (ignore_message)
+    *otr_data = NULL;
+
+  if (!ignore_message && newmessage) {
+    *free_msg = 1;
+    *otr_data = html_strip(newmessage);
+    otrl_message_free(newmessage);
+    if (ctx->msgstate == OTRL_MSGSTATE_ENCRYPTED)
+      return 1;
+  }
+  return 0;
+}
+
+int otr_send(char **msg, const char *buddy)
+{
+  gcry_error_t err;
+  char *newmessage = NULL;
+  char *htmlmsg;
+  ConnContext *ctx = otr_get_context(buddy);
+
+  if (ctx->msgstate == OTRL_MSGSTATE_PLAINTEXT)
+    err = otrl_message_sending(userstate, &ops, NULL, ctx->accountname,
+                               ctx->protocol, ctx->username, *msg, NULL,
+                               &newmessage, NULL, NULL);
+  else {
+    htmlmsg = html_escape(*msg);
+    err = otrl_message_sending(userstate, &ops, NULL, ctx->accountname,
+                               ctx->protocol, ctx->username, htmlmsg, NULL,
+                               &newmessage, NULL, NULL);
+    g_free(htmlmsg);
+  }
+
+  if (err)
+    *msg = NULL; /*something went wrong, don't send the plain-message! */
+
+  if (!err && newmessage) {
+    *msg = g_strdup(newmessage);
+    otrl_message_free(newmessage);
+    if (cb_policy(NULL, ctx) & OTRL_POLICY_REQUIRE_ENCRYPTION ||
+        ctx->msgstate == OTRL_MSGSTATE_ENCRYPTED)
+      return 1;
+  }
+  return 0;
+}
+
+/* Prints OTR connection state */
+void otr_print_info(const char *buddy)
+{
+  const char *state, *auth, *policy;
+  ConnContext *ctx = otr_get_context(buddy);
+  OtrlPolicy p = cb_policy(ctx->app_data, ctx);
+
+  if (!userstate || !ctx)
+    return;
+
+  switch (ctx->msgstate) {
+    case OTRL_MSGSTATE_PLAINTEXT: state = "plaintext"; break;
+    case OTRL_MSGSTATE_ENCRYPTED:
+     switch (ctx->protocol_version) {
+       case 1: state = "encrypted V1"; break;
+       case 2: state = "encrypted V2"; break;
+       default:state = "encrypted";
+     };
+     break;
+    case OTRL_MSGSTATE_FINISHED:  state = "finished";  break;
+    default:                      state = "unknown state";
+  }
+  switch (ctx->auth.authstate) {
+    case OTRL_AUTHSTATE_NONE:
+      switch (ctx->otr_offer) {
+        case OFFER_NOT:      auth = "no offer sent";  break;
+        case OFFER_SENT:     auth = "offer sent";     break;
+        case OFFER_ACCEPTED: auth = "offer accepted"; break;
+        case OFFER_REJECTED: auth = "offer rejected"; break;
+        default:             auth = "unknown auth";
+      }
+      break;
+    case OTRL_AUTHSTATE_AWAITING_DHKEY:
+      auth = "awaiting D-H key";          break;
+    case OTRL_AUTHSTATE_AWAITING_REVEALSIG:
+      auth = "awaiting reveal signature"; break;
+    case OTRL_AUTHSTATE_AWAITING_SIG:
+      auth = "awaiting signature";        break;
+    case OTRL_AUTHSTATE_V1_SETUP:
+      auth = "v1 setup";                  break;
+    default:
+      auth = "unknown auth";
+  }
+  if (p == OTRL_POLICY_NEVER)
+    policy = "plain";
+  else if (p == (OTRL_POLICY_OPPORTUNISTIC & ~OTRL_POLICY_ALLOW_V1))
+    policy = "opportunistic";
+  else if (p == (OTRL_POLICY_MANUAL & ~OTRL_POLICY_ALLOW_V1))
+    policy = "manual";
+  else if (p == (OTRL_POLICY_ALWAYS & ~OTRL_POLICY_ALLOW_V1))
+    policy = "always";
+  else
+    policy = "unknown";
+
+  scr_LogPrint(LPRINT_LOGNORM, "%s: %s (%s) [%s]",
+               ctx->username, state, auth, policy);
+}
+
+static ConnContext *otr_context_encrypted(const char *buddy)
+{
+  ConnContext *ctx = otr_get_context(buddy);
+
+  if (!userstate || !ctx  || ctx->msgstate != OTRL_MSGSTATE_ENCRYPTED){
+    scr_LogPrint(LPRINT_LOGNORM,
+                 "You have to start an OTR channel with %s before you can "
+                 "use SMP.", buddy);
+    return NULL;
+  }
+
+  return ctx;
+}
+
+void otr_smp_query(const char *buddy, const char *secret)
+{
+  ConnContext *ctx = otr_context_encrypted(buddy);
+
+  if (!secret) {
+    scr_LogPrint(LPRINT_LOGNORM,
+                 "Using SMP without a secret isn't a good idea.");
+    return;
+  }
+
+  if (ctx) {
+    otrl_message_initiate_smp(userstate, &ops, NULL, ctx,
+                              (const unsigned char *)secret,
+                              strlen(secret));
+    scr_WriteIncomingMessage(ctx->username,
+                             "OTR: Socialist Millionaires' Protocol "
+                             "initiated.", 0, HBB_PREFIX_INFO, 0);
+  }
+}
+
+void otr_smp_respond(const char *buddy, const char *secret)
+{
+  ConnContext *ctx = otr_context_encrypted(buddy);
+
+  if (!secret) {
+    scr_LogPrint(LPRINT_LOGNORM,
+                 "Using SMP without a secret isn't a good idea.");
+    return;
+  }
+
+  if (ctx) {
+    if (!ctx->smstate->secret) {
+      scr_LogPrint(LPRINT_LOGNORM,
+                   "Don't call smpr until you have received an SMP "
+                   "Initiation!");
+      return;
+    }
+    otrl_message_respond_smp(userstate, &ops, NULL, ctx,
+                             (const unsigned char *)secret,
+                             strlen(secret));
+    scr_WriteIncomingMessage(ctx->username,
+                             "OTR: Socialist Millionaires' Protocol: "
+                             "response sent", 0, HBB_PREFIX_INFO, 0);
+  }
+}
+
+void otr_smp_abort(const char *buddy)
+{
+  ConnContext *ctx = otr_context_encrypted(buddy);
+
+  if (ctx) {
+    otrl_message_abort_smp(userstate, &ops, NULL, ctx);
+    scr_WriteIncomingMessage(ctx->username,
+                             "OTR: Socialist Millionaires' Protocol aborted.",
+                             0, HBB_PREFIX_INFO, 0);
+  }
+}
+
+void otr_key(void)
+{
+  OtrlPrivKey *key;
+  char readable[45] = "";
+
+  if(!userstate)
+    return;
+  for (key = userstate->privkey_root; key; key = key->next) {
+    otrl_privkey_fingerprint(userstate, readable, key->accountname,
+                             key->protocol);
+    scr_LogPrint(LPRINT_LOGNORM, "%s: %s", key->accountname, readable);
+  }
+}
+
+/* Return the OTR policy for the given context. */
+static OtrlPolicy cb_policy(void *opdata, ConnContext *ctx)
+{
+  enum otr_policy p = settings_otr_getpolicy(NULL);
+
+  if(ctx)
+    if(settings_otr_getpolicy(ctx->username))
+      p = settings_otr_getpolicy(ctx->username);
+
+  switch (p) {
+    case plain:
+      return OTRL_POLICY_NEVER;
+    case opportunistic:
+      return OTRL_POLICY_OPPORTUNISTIC & ~OTRL_POLICY_ALLOW_V1;
+    case manual:
+      return OTRL_POLICY_MANUAL & ~OTRL_POLICY_ALLOW_V1;
+    case always:
+      return OTRL_POLICY_ALWAYS & ~OTRL_POLICY_ALLOW_V1;
+  }
+
+  return OTRL_POLICY_MANUAL & ~OTRL_POLICY_ALLOW_V1;
+}
+
+/* Create a private key for the given accountname/protocol if
+ * desired. */
+static void cb_create_privkey(void *opdata, const char *accountname,
+                              const char *protocol)
+{
+  gcry_error_t e;
+  char *root;
+
+  scr_LogPrint(LPRINT_LOGNORM,
+               "Generating new OTR key for %s. This may take a while...",
+               accountname);
+  scr_DoUpdate();
+
+  e = otrl_privkey_generate(userstate, keyfile, accountname, protocol);
+
+  if (e) {
+    root = otr_get_dir();
+    scr_LogPrint(LPRINT_LOGNORM, "OTR key generation failed! Please mkdir "
+                 "%s if you want to use otr encryption.", root);
+    g_free(root);
+  }
+  else
+    scr_LogPrint(LPRINT_LOGNORM, "OTR key generated.");
+}
+
+/* Report whether you think the given user is online.  Return 1 if
+ * you think he is, 0 if you think he isn't, -1 if you're not sure.
+ * If you return 1, messages such as heartbeats or other
+ * notifications may be sent to the user, which could result in "not
+ * logged in" errors if you're wrong. */
+static int cb_is_logged_in(void *opdata, const char *accountname,
+                           const char *protocol, const char *recipient)
+{
+  int ret = (roster_getstatus(recipient, NULL) != offline);
+  return ret;
+}
+
+/* Send the given IM to the given recipient from the given
+ * accountname/protocol. */
+static void cb_inject_message(void *opdata, const char *accountname,
+                              const char *protocol, const char *recipient,
+                              const char *message)
+{
+  if (roster_gettype(recipient) == ROSTER_TYPE_USER)
+    xmpp_send_msg(recipient, message, ROSTER_TYPE_USER, "", TRUE, NULL,
+                  LM_MESSAGE_SUB_TYPE_NOT_SET, NULL);
+}
+
+/* Display a notification message for a particular
+ * accountname / protocol / username conversation. */
+static void cb_notify(void *opdata, OtrlNotifyLevel level,
+                      const char *accountname, const char *protocol,
+                      const char *username, const char *title,
+                      const char *primary, const char *secondary)
+{
+  char *type;
+  char *sbuf = NULL;
+  switch (level) {
+    case OTRL_NOTIFY_ERROR:   type = "error";   break;
+    case OTRL_NOTIFY_WARNING: type = "warning"; break;
+    case OTRL_NOTIFY_INFO:    type = "info";    break;
+    default:                  type = "unknown";
+  }
+  sbuf = g_strdup_printf("OTR %s:%s\n%s\n%s",type,title, primary, secondary);
+  scr_WriteIncomingMessage(username, sbuf, 0, HBB_PREFIX_INFO, 0);
+  g_free(sbuf);
+}
+
+/* Display an OTR control message for a particular
+ * accountname / protocol / username conversation.  Return 0 if you are able
+ * to successfully display it.  If you return non-0 (or if this
+ * function is NULL), the control message will be displayed inline,
+ * as a received message, or else by using the above notify()
+ * callback. */
+static int cb_display_otr_message(void *opdata, const char *accountname,
+                                  const char *protocol, const char *username,
+                                  const char *msg)
+{
+  char *strippedmsg = html_strip(msg);
+  scr_WriteIncomingMessage(username, strippedmsg, 0, HBB_PREFIX_INFO, 0);
+  g_free(strippedmsg);
+  return 0;
+}
+
+/* When the list of ConnContexts changes (including a change in
+ * state), this is called so the UI can be updated. */
+static void cb_update_context_list(void *opdata)
+{
+  /*maybe introduce new status characters for mcabber,
+   * then use this function (?!)*/
+}
+
+/* Return a newly allocated string containing a human-friendly name
+ * for the given protocol id */
+static const char *cb_protocol_name(void *opdata, const char *protocol)
+{
+  return protocol;
+}
+
+/* Deallocate a string allocated by protocol_name */
+static void cb_protocol_name_free (void *opdata, const char *protocol_name)
+{
+  /* We didn't allocated memory, so we don't have to free anything :p */
+}
+
+/* A new fingerprint for the given user has been received. */
+static void cb_new_fingerprint(void *opdata, OtrlUserState us,
+                               const char *accountname, const char *protocol,
+                               const char *username,
+                               unsigned char fingerprint[20])
+{
+  char *sbuf = NULL;
+  char readable[45];
+
+  otrl_privkey_hash_to_human(readable, fingerprint);
+  sbuf = g_strdup_printf("OTR: new fingerprint: %s", readable);
+  scr_WriteIncomingMessage(username, sbuf, 0, HBB_PREFIX_INFO, 0);
+  g_free(sbuf);
+}
+
+/* The list of known fingerprints has changed.  Write them to disk. */
+static void cb_write_fingerprints(void *opdata)
+{
+  otrl_privkey_write_fingerprints(userstate, fprfile);
+}
+
+/* A ConnContext has entered a secure state. */
+static void cb_gone_secure(void *opdata, ConnContext *context)
+{
+  scr_WriteIncomingMessage(context->username, "OTR: channel established", 0,
+                           HBB_PREFIX_INFO, 0);
+}
+
+/* A ConnContext has left a secure state. */
+static void cb_gone_insecure(void *opdata, ConnContext *context)
+{
+  scr_WriteIncomingMessage(context->username, "OTR: channel closed", 0,
+                           HBB_PREFIX_INFO, 0);
+}
+
+/* We have completed an authentication, using the D-H keys we
+ * already knew.  is_reply indicates whether we initiated the AKE. */
+static void cb_still_secure(void *opdata, ConnContext *context, int is_reply)
+{
+  scr_WriteIncomingMessage(context->username, "OTR: channel reestablished", 0,
+                           HBB_PREFIX_INFO, 0);
+}
+
+/* Log a message.  The passed message will end in "\n". */
+static void cb_log_message(void *opdata, const char *message)
+{
+  scr_LogPrint(LPRINT_DEBUG, "OTR: %s", message);
+}
+
+/* Find the maximum message size supported by this protocol. */
+static int cb_max_message_size(void *opdata, ConnContext *context)
+{
+  return 8192;
+}
+
+int otr_enabled(void)
+{
+  return otr_is_enabled;
+}
+
+#else /* !HAVE_LIBOTR */
+
+int otr_enabled(void)
+{
+  return FALSE;
+}
+
+#endif /* HAVE_LIBOTR */
+
+/* vim: set expandtab cindent cinoptions=>2\:2(0:  For Vim users... */