OTR support, first checkin

1 files changed, 953 insertions, 0 deletions

diff --git a/otr.c b/otr.c
new file mode 100644
index 00000000..2b920f4b
--- /dev/null
+++ b/otr.c
@@ -0,0 +1,953 @@
+#include "bitlbee.h"
+#ifdef WITH_OTR
+#include "irc.h"
+#include "otr.h"
+#include <sys/types.h>
+#include <unistd.h>
+
+/**
+files used to store OTR data:
+  $configdir/$nick.otr_keys
+  $configdir/$nick.otr_fprints
+ **/
+
+
+/** OTR interface routines for the OtrlMessageAppOps struct: **/
+
+OtrlPolicy op_policy(void *opdata, ConnContext *context);
+
+void op_create_privkey(void *opdata, const char *accountname, const char *protocol);
+
+int op_is_logged_in(void *opdata, const char *accountname, const char *protocol,
+	const char *recipient);
+
+void op_inject_message(void *opdata, const char *accountname, const char *protocol,
+	const char *recipient, const char *message);
+
+int op_display_otr_message(void *opdata, const char *accountname, const char *protocol,
+	const char *username, const char *msg);
+
+void op_new_fingerprint(void *opdata, OtrlUserState us, const char *accountname,
+	const char *protocol, const char *username, unsigned char fingerprint[20]);
+
+void op_write_fingerprints(void *opdata);
+
+void op_gone_secure(void *opdata, ConnContext *context);
+
+void op_gone_secure(void *opdata, ConnContext *context);
+
+void op_gone_insecure(void *opdata, ConnContext *context);
+
+void op_still_secure(void *opdata, ConnContext *context, int is_reply);
+
+void op_log_message(void *opdata, const char *message);
+
+/* TODO: int op_max_message_size(void *opdata, ConnContext *context); */
+
+/* TODO: const char *op_account_name(void *opdata, const char *account,
+	const char *protocol); */
+
+
+/** otr sub-command handlers: **/
+
+/* TODO: void cmd_otr_keygen(irc_t *irc, char **args); */
+void cmd_otr_abort(irc_t *irc, char **args); /* TODO: does this cmd even make sense? */
+void cmd_otr_request(irc_t *irc, char **args); /* TODO: do we even need this? */
+void cmd_otr_auth(irc_t *irc, char **args);
+/* TODO: void cmd_otr_affirm(irc_t *irc, char **args); */
+void cmd_otr_fprints(irc_t *irc, char **args);
+void cmd_otr_info(irc_t *irc, char **args);
+void cmd_otr_policy(irc_t *irc, char **args);
+
+const command_t otr_commands[] = {
+	{ "abort",    1, &cmd_otr_abort,    0 },
+	{ "request",  1, &cmd_otr_request,  0 },
+	{ "auth",     2, &cmd_otr_auth,     0 },
+	{ "fprints",  0, &cmd_otr_fprints,  0 },
+	{ "info",     1, &cmd_otr_info,     0 },
+	{ "policy",   0, &cmd_otr_policy,   0 },
+	{ NULL }
+};
+
+
+/** misc. helpers/subroutines: **/
+
+/* start background thread to generate a (new) key for a given account */
+void otr_keygen(irc_t *irc, const char *handle, const char *protocol);
+/* keygen thread main func */
+gpointer otr_keygen_thread_func(gpointer data);
+/* mainloop handler for when keygen thread finishes */
+gboolean keygen_finish_handler(gpointer data, gint fd, b_input_condition cond);
+/* data to be passed to otr_keygen_thread_func */
+struct kgdata {
+	irc_t *irc;            /* access to OTR userstate */
+	char *keyfile;         /* free me! */
+	const char *handle;      /* don't free! */
+	const char *protocol;    /* don't free! */
+	GMutex *mutex;         /* lock for the 'done' flag, free me! */
+	int done;              /* is the thread done? */
+	gcry_error_t result;   /* return value of otrl_privkey_generate */
+};
+
+/* yes/no handlers for "generate key now?" */
+void yes_keygen(gpointer w, void *data);
+void no_keygen(gpointer w, void *data);
+
+/* helper to make sure accountname and protocol match the incoming "opdata" */
+struct im_connection *check_imc(void *opdata, const char *accountname,
+	const char *protocol);
+
+/* determine the nick for a given handle/protocol pair */
+const char *peernick(irc_t *irc, const char *handle, const char *protocol);
+
+/* handle SMP TLVs from a received message */
+void otr_handle_smp(struct im_connection *ic, const char *handle, OtrlTLV *tlvs);
+
+/* show the list of fingerprints associated with a given context */
+void show_fingerprints(irc_t *irc, ConnContext *ctx);
+
+
+
+/*** routines declared in otr.h: ***/
+
+void otr_init(void)
+{
+	if(!g_thread_supported()) g_thread_init(NULL);
+	OTRL_INIT;
+	
+	/* fill global OtrlMessageAppOps */
+	global.otr_ops.policy = &op_policy;
+	global.otr_ops.create_privkey = &op_create_privkey;
+	global.otr_ops.is_logged_in = &op_is_logged_in;
+	global.otr_ops.inject_message = &op_inject_message;
+	global.otr_ops.notify = NULL;
+	global.otr_ops.display_otr_message = &op_display_otr_message;
+	global.otr_ops.update_context_list = NULL;
+	global.otr_ops.protocol_name = NULL;
+	global.otr_ops.protocol_name_free = NULL;
+	global.otr_ops.new_fingerprint = &op_new_fingerprint;
+	global.otr_ops.write_fingerprints = &op_write_fingerprints;
+	global.otr_ops.gone_secure = &op_gone_secure;
+	global.otr_ops.gone_insecure = &op_gone_insecure;
+	global.otr_ops.still_secure = &op_still_secure;
+	global.otr_ops.log_message = &op_log_message;
+	global.otr_ops.max_message_size = NULL;
+	global.otr_ops.account_name = NULL;
+	global.otr_ops.account_name_free = NULL;
+}
+
+/* Notice on the otr_mutex:
+
+   The incoming/outgoing message handlers try to lock the otr_mutex. If they succeed,
+   this will prevent a concurrent keygen (possibly spawned by that very command)
+   from messing up the userstate. If the lock fails, that means there already is
+   a keygen in progress. Instead of blocking for an unknown time, they
+   will bail out gracefully, informing the user of this temporary "coma".
+   TODO: Hold back incoming/outgoing messages and process them when keygen completes?
+
+   The other routines do not lock the otr_mutex themselves, it is done as a
+   catch-all in the root command handler. Rationale:
+     a) it's easy to code
+     b) it makes it obvious that no command can get its userstate corrupted
+     c) the "irc" struct is readily available there for feedback to the user
+ */
+
+void otr_load(irc_t *irc)
+{
+	char s[512];
+	account_t *a;
+	gcry_error_t e;
+
+	log_message(LOGLVL_DEBUG, "otr_load '%s'", irc->nick);
+
+	g_snprintf(s, 511, "%s%s.otr_keys", global.conf->configdir, irc->nick);
+	e = otrl_privkey_read(irc->otr_us, s);
+	if(e && e!=ENOENT) {
+		log_message(LOGLVL_ERROR, "%s: %s", s, strerror(e));
+	}
+	g_snprintf(s, 511, "%s%s.otr_fprints", global.conf->configdir, irc->nick);
+	e = otrl_privkey_read_fingerprints(irc->otr_us, s, NULL, NULL);
+	if(e && e!=ENOENT) {
+		log_message(LOGLVL_ERROR, "%s: %s", s, strerror(e));
+	}
+	
+	/* check for otr keys on all accounts */
+	for(a=irc->accounts; a; a=a->next) {
+		otr_check_for_key(a);
+	}
+}
+
+void otr_save(irc_t *irc)
+{
+	char s[512];
+
+	log_message(LOGLVL_DEBUG, "otr_save '%s'", irc->nick);
+
+	g_snprintf(s, 511, "%s%s.otr_fprints", global.conf->configdir, irc->nick);
+	otrl_privkey_write_fingerprints(irc->otr_us, s);
+}
+
+void otr_remove(const char *nick)
+{
+	char s[512];
+	
+	log_message(LOGLVL_DEBUG, "otr_remove '%s'", nick);
+
+	g_snprintf(s, 511, "%s%s.otr_keys", global.conf->configdir, nick);
+	unlink(s);
+	g_snprintf(s, 511, "%s%s.otr_fprints", global.conf->configdir, nick);
+	unlink(s);
+}
+
+void otr_rename(const char *onick, const char *nnick)
+{
+	char s[512], t[512];
+	
+	log_message(LOGLVL_DEBUG, "otr_rename '%s' -> '%s'", onick, nnick);
+
+	g_snprintf(s, 511, "%s%s.otr_keys", global.conf->configdir, onick);
+	g_snprintf(t, 511, "%s%s.otr_keys", global.conf->configdir, nnick);
+	rename(s,t);
+	g_snprintf(s, 511, "%s%s.otr_fprints", global.conf->configdir, onick);
+	g_snprintf(t, 511, "%s%s.otr_fprints", global.conf->configdir, nnick);
+	rename(s,t);
+}
+
+void otr_check_for_key(account_t *a)
+{
+	irc_t *irc = a->irc;
+	char buf[45];
+	char *fp;
+	
+	fp = otrl_privkey_fingerprint(irc->otr_us, buf, a->user, a->prpl->name);
+	if(fp) {
+		irc_usermsg(irc, "otr: %s/%s ready with f'print %s",
+			a->user, a->prpl->name, fp);
+	} else {
+		otr_keygen(irc, a->user, a->prpl->name);
+	}
+}
+
+char *otr_handle_message(struct im_connection *ic, const char *handle, const char *msg)
+{
+	int ignore_msg;
+	char *newmsg = NULL;
+	OtrlTLV *tlvs = NULL;
+	char *colormsg;
+	
+    if(!g_mutex_trylock(ic->irc->otr_mutex)) {
+    	/* TODO: queue msgs received during keygen for later */
+		irc_usermsg(ic->irc, "msg from %s/%s during keygen - dropped",
+			handle, ic->acc->prpl->name);
+		return NULL;
+	}
+
+	ignore_msg = otrl_message_receiving(ic->irc->otr_us, &global.otr_ops, ic,
+		ic->acc->user, ic->acc->prpl->name, handle, msg, &newmsg,
+		&tlvs, NULL, NULL);
+
+	otr_handle_smp(ic, handle, tlvs);
+	
+	if(ignore_msg) {
+		/* this was an internal OTR protocol message */
+		g_mutex_unlock(ic->irc->otr_mutex);
+		return NULL;
+	} else if(!newmsg) {
+		/* this was a non-OTR message */
+		g_mutex_unlock(ic->irc->otr_mutex);
+		return g_strdup(msg);
+	} else {
+		/* OTR has processed this message */
+		ConnContext *context = otrl_context_find(ic->irc->otr_us, handle,
+			ic->acc->user, ic->acc->prpl->name, 0, NULL, NULL, NULL);
+		if(context && context->msgstate == OTRL_MSGSTATE_ENCRYPTED) {
+			/* color according to f'print trust */
+			char color;
+			const char *trust = context->active_fingerprint->trust;
+			if(trust && trust[0] != '\0')
+				color='3';   /* green */
+			else
+				color='5';   /* red */
+			colormsg = g_strdup_printf("\x03%c%s\x0F", color, newmsg);
+		} else {
+			colormsg = g_strdup(newmsg);
+		}
+		otrl_message_free(newmsg);
+		g_mutex_unlock(ic->irc->otr_mutex);
+		return colormsg;
+	}
+}
+
+int otr_send_message(struct im_connection *ic, const char *handle, const char *msg, int flags)
+{	
+    int st;
+    char *otrmsg = NULL;
+    ConnContext *ctx = NULL;
+    
+    if(!g_mutex_trylock(ic->irc->otr_mutex)) {
+    	irc_usermsg(ic->irc, "msg to %s/%s during keygen - not sent",
+    		handle, ic->acc->prpl->name);
+    	return 1;
+    }
+    
+	st = otrl_message_sending(ic->irc->otr_us, &global.otr_ops, ic,
+		ic->acc->user, ic->acc->prpl->name, handle,
+		msg, NULL, &otrmsg, NULL, NULL);
+	if(st) {
+		g_mutex_unlock(ic->irc->otr_mutex);
+		return st;
+	}
+
+	ctx = otrl_context_find(ic->irc->otr_us,
+			handle, ic->acc->user, ic->acc->prpl->name,
+			1, NULL, NULL, NULL);
+
+	if(otrmsg) {
+		if(!ctx) {
+			otrl_message_free(otrmsg);
+			g_mutex_unlock(ic->irc->otr_mutex);
+			return 1;
+		}
+		st = otrl_message_fragment_and_send(&global.otr_ops, ic, ctx,
+			otrmsg, OTRL_FRAGMENT_SEND_ALL, NULL);
+		otrl_message_free(otrmsg);
+	} else {
+		/* yeah, well, some const casts as usual... ;-) */
+		st = ic->acc->prpl->buddy_msg( ic, (char *)handle, (char *)msg, flags );
+	}
+	
+	g_mutex_unlock(ic->irc->otr_mutex);
+	return st;
+}
+
+void cmd_otr(irc_t *irc, char **args)
+{
+	const command_t *cmd;
+	
+	if(!args[0])
+		return;
+	
+	if(!args[1])
+		return;
+	
+	for(cmd=otr_commands; cmd->command; cmd++) {
+		if(strcmp(cmd->command, args[1]) == 0)
+			break;
+	}
+	
+	if(!cmd->command) {
+		irc_usermsg(irc, "%s %s: unknown subcommand, see \x02help otr\x02",
+			args[0], args[1]);
+		return;
+	}
+	
+	if(!args[cmd->required_parameters+1]) {
+		irc_usermsg(irc, "%s %s: not enough arguments (%d req.)",
+			args[0], args[1], cmd->required_parameters);
+		return;
+	}
+	
+	cmd->execute(irc, args+1);
+}
+
+
+/*** OTR "MessageAppOps" callbacks for global.otr_ui: ***/
+
+OtrlPolicy op_policy(void *opdata, ConnContext *context)
+{
+	/* TODO: OTR policy configurable */
+	return OTRL_POLICY_OPPORTUNISTIC;
+}
+
+void op_create_privkey(void *opdata, const char *accountname,
+	const char *protocol)
+{
+	struct im_connection *ic = check_imc(opdata, accountname, protocol);
+	char *s;
+	
+	log_message(LOGLVL_DEBUG, "op_create_privkey '%s' '%s'", accountname, protocol);
+
+	s = g_strdup_printf("oops, no otr privkey for %s/%s - generate one now?",
+		accountname, protocol);
+	query_add(ic->irc, ic, s, yes_keygen, no_keygen, ic->acc);
+}
+
+int op_is_logged_in(void *opdata, const char *accountname,
+	const char *protocol, const char *recipient)
+{
+	struct im_connection *ic = check_imc(opdata, accountname, protocol);
+	user_t *u;
+
+	log_message(LOGLVL_DEBUG, "op_is_logged_in '%s' '%s' '%s'", accountname, protocol, recipient);
+	
+	/* lookup the user_t for the given recipient */
+	u = user_findhandle(ic, recipient);
+	if(u) {
+		if(u->online)
+			return 1;
+		else
+			return 0;
+	} else {
+		return -1;
+	}
+}
+
+void op_inject_message(void *opdata, const char *accountname,
+	const char *protocol, const char *recipient, const char *message)
+{
+	struct im_connection *ic = check_imc(opdata, accountname, protocol);
+
+	log_message(LOGLVL_DEBUG, "op_inject_message '%s' '%s' '%s' '%s'", accountname, protocol, recipient, message);
+
+	if (strcmp(accountname, recipient) == 0) {
+		/* huh? injecting messages to myself? */
+		irc_usermsg(ic->irc, "note to self: %s", message);
+	} else {
+		/* need to drop some consts here :-( */
+		/* TODO: get flags into op_inject_message?! */
+		ic->acc->prpl->buddy_msg(ic, (char *)recipient, (char *)message, 0);
+		/* ignoring return value :-/ */
+	}
+}
+
+int op_display_otr_message(void *opdata, const char *accountname,
+	const char *protocol, const char *username, const char *msg)
+{
+	struct im_connection *ic = check_imc(opdata, accountname, protocol);
+
+	log_message(LOGLVL_DEBUG, "op_display_otr_message '%s' '%s' '%s' '%s'", accountname, protocol, username, msg);
+
+	irc_usermsg(ic->irc, "%s", msg);
+
+	return 0;
+}
+
+void op_new_fingerprint(void *opdata, OtrlUserState us,
+	const char *accountname, const char *protocol,
+	const char *username, unsigned char fingerprint[20])
+{
+	struct im_connection *ic = check_imc(opdata, accountname, protocol);
+	char hunam[45];		/* anybody looking? ;-) */
+	
+	otrl_privkey_hash_to_human(hunam, fingerprint);
+	log_message(LOGLVL_DEBUG, "op_new_fingerprint '%s' '%s' '%s' '%s'", accountname, protocol, username, hunam);
+
+	irc_usermsg(ic->irc, "new fingerprint for %s: %s",
+		peernick(ic->irc, username, protocol), hunam);
+}
+
+void op_write_fingerprints(void *opdata)
+{
+	struct im_connection *ic = (struct im_connection *)opdata;
+
+	log_message(LOGLVL_DEBUG, "op_write_fingerprints");
+
+	otr_save(ic->irc);
+}
+
+void op_gone_secure(void *opdata, ConnContext *context)
+{
+	struct im_connection *ic =
+		check_imc(opdata, context->accountname, context->protocol);
+
+	log_message(LOGLVL_DEBUG, "op_gone_secure '%s' '%s' '%s'", context->accountname, context->protocol, context->username);
+
+	irc_usermsg(ic->irc, "conversation with %s is now off the record",
+		peernick(ic->irc, context->username, context->protocol));
+}
+
+void op_gone_insecure(void *opdata, ConnContext *context)
+{
+	struct im_connection *ic =
+		check_imc(opdata, context->accountname, context->protocol);
+
+	log_message(LOGLVL_DEBUG, "op_gone_insecure '%s' '%s' '%s'", context->accountname, context->protocol, context->username);
+
+	irc_usermsg(ic->irc, "conversation with %s is now in the clear",
+		peernick(ic->irc, context->username, context->protocol));
+}
+
+void op_still_secure(void *opdata, ConnContext *context, int is_reply)
+{
+	struct im_connection *ic =
+		check_imc(opdata, context->accountname, context->protocol);
+
+	log_message(LOGLVL_DEBUG, "op_still_secure '%s' '%s' '%s' is_reply=%d",
+		context->accountname, context->protocol, context->username, is_reply);
+
+	irc_usermsg(ic->irc, "otr connection with %s has been refreshed",
+		peernick(ic->irc, context->username, context->protocol));
+}
+
+void op_log_message(void *opdata, const char *message)
+{
+	log_message(LOGLVL_INFO, "%s", message);
+}
+
+
+/*** OTR sub-command handlers ***/
+
+void cmd_otr_abort(irc_t *irc, char **args)
+{
+	user_t *u;
+
+	u = user_find(irc, args[1]);
+	if(!u || !u->ic) {
+		irc_usermsg(irc, "%s: unknown user", args[1]);
+		return;
+	}
+	
+	otrl_message_disconnect(irc->otr_us, &global.otr_ops,
+		u->ic, u->ic->acc->user, u->ic->acc->prpl->name, u->handle);
+}
+
+void cmd_otr_request(irc_t *irc, char **args)
+{
+	user_t *u;
+
+	u = user_find(irc, args[1]);
+	if(!u || !u->ic) {
+		irc_usermsg(irc, "%s: unknown user", args[1]);
+		return;
+	}
+	if(!u->online) {
+		irc_usermsg(irc, "%s is offline", args[1]);
+		return;
+	}
+	
+	imc_buddy_msg(u->ic, u->handle, "?OTR?", 0);
+}
+
+void cmd_otr_auth(irc_t *irc, char **args)
+{
+	user_t *u;
+	ConnContext *ctx;
+	
+	u = user_find(irc, args[1]);
+	if(!u || !u->ic) {
+		irc_usermsg(irc, "%s: unknown user", args[1]);
+		return;
+	}
+	if(!u->online) {
+		irc_usermsg(irc, "%s is offline", args[1]);
+		return;
+	}
+	
+	ctx = otrl_context_find(irc->otr_us, u->handle,
+		u->ic->acc->user, u->ic->acc->prpl->name, 1, NULL, NULL, NULL);
+	if(!ctx) {
+		return;
+	}
+
+	if(ctx->smstate->nextExpected != OTRL_SMP_EXPECT1) {
+		log_message(LOGLVL_INFO,
+			"SMP already in phase %d, sending abort before reinitiating",
+			ctx->smstate->nextExpected+1);
+		otrl_message_abort_smp(irc->otr_us, &global.otr_ops, u->ic, ctx);
+		otrl_sm_state_free(ctx->smstate);
+	}
+	
+	/* warning: the following assumes that smstates are cleared whenever an SMP
+	   is completed or aborted! */ 
+	if(ctx->smstate->secret == NULL) {
+		irc_usermsg(irc, "smp: initiating with %s...", u->nick);
+		otrl_message_initiate_smp(irc->otr_us, &global.otr_ops,
+			u->ic, ctx, (unsigned char *)args[2], strlen(args[2]));
+		/* smp is now in EXPECT2 */
+	} else {
+		/* if we're still in EXPECT1 but smstate is initialized, we must have
+		   received the SMP1, so let's issue a response */
+		irc_usermsg(irc, "smp: responding to %s...", u->nick);
+		otrl_message_respond_smp(irc->otr_us, &global.otr_ops,
+			u->ic, ctx, (unsigned char *)args[2], strlen(args[2]));
+		/* smp is now in EXPECT3 */
+	}
+}
+
+void cmd_otr_fprints(irc_t *irc, char **args)
+{
+	if(args[1]) {
+		/* list given buddy's fingerprints */
+		user_t *u;
+		ConnContext *ctx;
+	
+		u = user_find(irc, args[1]);
+		if(!u || !u->ic) {
+			irc_usermsg(irc, "%s: unknown user", args[1]);
+			return;
+		}
+	
+		ctx = otrl_context_find(irc->otr_us, u->handle,
+			u->ic->acc->user, u->ic->acc->prpl->name, 0, NULL, NULL, NULL);
+		if(!ctx) {
+			irc_usermsg(irc, "no fingerprints");
+		} else {
+			show_fingerprints(irc, ctx);
+		}
+	} else {
+		/* list all known fingerprints */
+		ConnContext *ctx;
+		for(ctx=irc->otr_us->context_root; ctx; ctx=ctx->next) {
+			irc_usermsg(irc, "[%s]", peernick(irc, ctx->username, ctx->protocol));
+			show_fingerprints(irc, ctx);
+		}
+		if(!irc->otr_us->context_root) {
+			irc_usermsg(irc, "no fingerprints");
+		}
+	}
+}
+
+void cmd_otr_info(irc_t *irc, char **args)
+{
+	user_t *u;
+	ConnContext *ctx;
+	Fingerprint *fp;
+	char human[45];
+	const char *offer_status;
+	const char *message_state;
+	const char *trust;
+
+	if(!args) {
+		irc_usermsg(irc, "no args?!");
+		return;
+	}
+	if(!args[1]) {
+		irc_usermsg(irc, "no args[1]?!");
+		return;
+	}
+	u = user_find(irc, args[1]);
+	if(!u || !u->ic) {
+		irc_usermsg(irc, "%s: unknown user", args[1]);
+		return;
+	}
+	
+	ctx = otrl_context_find(irc->otr_us, u->handle,
+		u->ic->acc->user, u->ic->acc->prpl->name, 0, NULL, NULL, NULL);
+	if(!ctx) {
+		irc_usermsg(irc, "no otr info on %s", args[1]);
+		return;
+	}
+
+	switch(ctx->otr_offer) {
+	case OFFER_NOT:       offer_status="none sent";          break;
+	case OFFER_SENT:      offer_status="awaiting reply";     break;
+	case OFFER_ACCEPTED:  offer_status="accepted our offer"; break;
+	case OFFER_REJECTED:  offer_status="ignored our offer";  break;
+	default:              offer_status="?";
+	}
+
+	switch(ctx->msgstate) {
+	case OTRL_MSGSTATE_PLAINTEXT: message_state="cleartext"; break;
+	case OTRL_MSGSTATE_ENCRYPTED: message_state="encrypted"; break;
+	case OTRL_MSGSTATE_FINISHED:  message_state="shut down"; break;
+	default:                      message_state="?";
+	}
+
+	irc_usermsg(irc, "%s is %s/%s; we are %s/%s to them", args[1],
+		ctx->username, ctx->protocol, ctx->accountname, ctx->protocol);
+	irc_usermsg(irc, "  otr offer status: %s", offer_status);
+	irc_usermsg(irc, "  connection state: %s", message_state);
+	irc_usermsg(irc, "  protocol version: %d", ctx->protocol_version);
+	fp = ctx->active_fingerprint;
+	if(!fp) {
+		irc_usermsg(irc, "  active f'print:   none");
+	} else {
+		otrl_privkey_hash_to_human(human, fp->fingerprint);
+		if(!fp->trust || fp->trust[0] == '\0') {
+			trust="untrusted";
+		} else {
+			trust=fp->trust;
+		}
+		irc_usermsg(irc, "  active f'print:   %s (%s)", human, trust);
+	}
+}
+
+void cmd_otr_policy(irc_t *irc, char **args)
+{
+	irc_usermsg(irc, "n/a: not implemented");
+}
+
+
+/*** local helpers / subroutines: ***/
+
+/* Socialist Millionaires' Protocol */
+void otr_handle_smp(struct im_connection *ic, const char *handle, OtrlTLV *tlvs)
+{
+	irc_t *irc = ic->irc;
+	OtrlUserState us = irc->otr_us;
+	OtrlMessageAppOps *ops = &global.otr_ops;
+	OtrlTLV *tlv = NULL;
+	ConnContext *context;
+	NextExpectedSMP nextMsg;
+	user_t *u;
+
+	u = user_findhandle(ic, handle);
+	if(!u) return;
+	context = otrl_context_find(us, handle,
+		ic->acc->user, ic->acc->prpl->name, 1, NULL, NULL, NULL);
+	if(!context) return;
+	nextMsg = context->smstate->nextExpected;
+
+	tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP1);
+	if (tlv) {
+		if (nextMsg != OTRL_SMP_EXPECT1) {
+			irc_usermsg(irc, "smp %s: spurious SMP1 received, aborting", u->nick);
+			otrl_message_abort_smp(us, ops, u->ic, context);
+			otrl_sm_state_free(context->smstate);
+		} else {
+			irc_usermsg(irc, "smp: initiated by %s"
+				" - respond with \x02otr smp %s <secret>\x02",
+				u->nick, u->nick);
+			/* smp stays in EXPECT1 until user responds */
+		}
+	}
+	tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP2);
+	if (tlv) {
+		if (nextMsg != OTRL_SMP_EXPECT2) {
+			irc_usermsg(irc, "smp %s: spurious SMP2 received, aborting", u->nick);
+			otrl_message_abort_smp(us, ops, u->ic, context);
+			otrl_sm_state_free(context->smstate);
+		} else {
+			/* SMP2 received, otrl_message_receiving will have sent SMP3 */
+			context->smstate->nextExpected = OTRL_SMP_EXPECT4;
+		}
+	}
+	tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP3);
+	if (tlv) {
+		if (nextMsg != OTRL_SMP_EXPECT3) {
+			irc_usermsg(irc, "smp %s: spurious SMP3 received, aborting", u->nick);
+			otrl_message_abort_smp(us, ops, u->ic, context);
+			otrl_sm_state_free(context->smstate);
+		} else {
+			/* SMP3 received, otrl_message_receiving will have sent SMP4 and set fp trust */
+			const char *trust = context->active_fingerprint->trust;
+			if(!trust || trust[0]=='\0') {
+				irc_usermsg(irc, "smp %s: secrets did not match, fingerprint not trusted",
+					u->nick);
+			} else {
+				irc_usermsg(irc, "smp %s: secrets proved equal, fingerprint trusted",
+					u->nick);
+			}
+			otrl_sm_state_free(context->smstate);
+			/* smp is in back in EXPECT1 */
+		}
+	}
+	tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP4);
+	if (tlv) {
+		if (nextMsg != OTRL_SMP_EXPECT4) {
+			irc_usermsg(irc, "smp %s: spurious SMP4 received, aborting", u->nick);
+			otrl_message_abort_smp(us, ops, u->ic, context);
+			otrl_sm_state_free(context->smstate);
+		} else {
+			/* SMP4 received, otrl_message_receiving will have set fp trust */
+			const char *trust = context->active_fingerprint->trust;
+			if(!trust || trust[0]=='\0') {
+				irc_usermsg(irc, "smp %s: secrets did not match, fingerprint not trusted",
+					u->nick);
+			} else {
+				irc_usermsg(irc, "smp %s: secrets proved equal, fingerprint trusted",
+					u->nick);
+			}
+			otrl_sm_state_free(context->smstate);
+			/* smp is in back in EXPECT1 */
+		}
+	}
+	tlv = otrl_tlv_find(tlvs, OTRL_TLV_SMP_ABORT);
+	if (tlv) {
+	 	irc_usermsg(irc, "smp: received abort from %s", u->nick);
+		otrl_sm_state_free(context->smstate);
+		/* smp is in back in EXPECT1 */
+	}
+}
+
+/* helper to assert that account and protocol names given to ops below always
+   match the im_connection passed through as opdata */
+struct im_connection *check_imc(void *opdata, const char *accountname,
+	const char *protocol)
+{
+	struct im_connection *ic = (struct im_connection *)opdata;
+
+	if (strcmp(accountname, ic->acc->user) != 0) {
+		log_message(LOGLVL_WARNING,
+			"otr: internal account name mismatch: '%s' vs '%s'",
+			accountname, ic->acc->user);
+	}
+	if (strcmp(protocol, ic->acc->prpl->name) != 0) {
+		log_message(LOGLVL_WARNING,
+			"otr: internal protocol name mismatch: '%s' vs '%s'",
+			protocol, ic->acc->prpl->name);
+	}
+	
+	return ic;
+}
+
+const char *peernick(irc_t *irc, const char *handle, const char *protocol)
+{
+	user_t *u;
+	static char fallback[512];
+	
+	g_snprintf(fallback, 511, "%s/%s", handle, protocol);
+	for(u=irc->users; u; u=u->next) {
+		struct prpl *prpl;
+		if(!u->ic || !u->handle)
+			break;
+		prpl = u->ic->acc->prpl;
+		if(strcmp(prpl->name, protocol) == 0
+			&& prpl->handle_cmp(u->handle, handle) == 0) {
+			return u->nick;
+		}
+	}
+	
+	return fallback;
+}
+
+void show_fingerprints(irc_t *irc, ConnContext *ctx)
+{
+	char human[45];
+	Fingerprint *fp;
+	const char *trust;
+	int count=0;
+	
+	for(fp=&ctx->fingerprint_root; fp; fp=fp->next) {
+		if(!fp->fingerprint)
+			continue;
+		count++;
+		otrl_privkey_hash_to_human(human, fp->fingerprint);
+		if(!fp->trust || fp->trust[0] == '\0') {
+			trust="untrusted";
+		} else {
+			trust=fp->trust;
+		}
+		if(fp == ctx->active_fingerprint) {
+			irc_usermsg(irc, "\x02%s (%s)\x02", human, trust);
+		} else {
+			irc_usermsg(irc, "%s (%s)", human, trust);
+		}
+	}
+	if(count==0)
+		irc_usermsg(irc, "no fingerprints");
+}
+
+void otr_keygen(irc_t *irc, const char *handle, const char *protocol)
+{
+	GError *err;
+	GThread *thr;
+	struct kgdata *kg;
+	gint ev;
+	
+	irc_usermsg(irc, "generating new otr privkey for %s/%s...",
+		handle, protocol);
+	
+	kg = g_new0(struct kgdata, 1);
+	if(!kg) {
+		irc_usermsg(irc, "otr keygen failed: out of memory");
+		return;
+	}
+
+	/* Assemble the job description to be passed to thread and handler */
+	kg->irc = irc;
+	kg->keyfile = g_strdup_printf("%s%s.otr_keys", global.conf->configdir, kg->irc->nick);
+	if(!kg->keyfile) {
+		irc_usermsg(irc, "otr keygen failed: out of memory");
+		g_free(kg);
+		return;
+	}
+	kg->handle = handle;
+	kg->protocol = protocol;
+	kg->mutex = g_mutex_new();
+	if(!kg->mutex) {
+		irc_usermsg(irc, "otr keygen failed: couldn't create mutex");
+		g_free(kg->keyfile);
+		g_free(kg);
+		return;
+	}
+	kg->done = FALSE;
+
+	/* Poll for completion of the thread periodically. I would have preferred
+	   to just wait on a pipe but this way it's portable to Windows. *sigh*
+	*/
+	ev = b_timeout_add(1000, &keygen_finish_handler, kg);
+	if(!ev) {
+		irc_usermsg(irc, "otr keygen failed: couldn't register timeout");
+		g_free(kg->keyfile);
+		g_mutex_free(kg->mutex);
+		g_free(kg);
+		return;
+	}
+
+	thr = g_thread_create(&otr_keygen_thread_func, kg, FALSE, &err);
+	if(!thr) {
+		irc_usermsg(irc, "otr keygen failed: %s", err->message);
+		g_free(kg->keyfile);
+		g_mutex_free(kg->mutex);
+		g_free(kg);
+		b_event_remove(ev);
+	}
+}
+
+gpointer otr_keygen_thread_func(gpointer data)
+{
+	struct kgdata *kg = (struct kgdata *)data;
+	
+	/* lock OTR subsystem and do the work */
+	g_mutex_lock(kg->irc->otr_mutex);
+	kg->result = otrl_privkey_generate(kg->irc->otr_us, kg->keyfile, kg->handle,
+		kg->protocol);
+	g_mutex_unlock(kg->irc->otr_mutex);
+	/* OTR enabled again */
+	
+	/* notify mainloop */
+	g_mutex_lock(kg->mutex);
+	kg->done = TRUE;
+	g_mutex_unlock(kg->mutex);
+	
+	return NULL;
+}
+
+gboolean keygen_finish_handler(gpointer data, gint fd, b_input_condition cond)
+{
+	struct kgdata *kg = (struct kgdata *)data;
+	int done;
+	
+	g_mutex_lock(kg->mutex);
+	done = kg->done;
+	g_mutex_unlock(kg->mutex);
+	if(kg->done) {
+		if(kg->result) {
+			irc_usermsg(kg->irc, "otr keygen failed: libgcrypt error"); /* TODO: diagnostics */
+		} else {
+			irc_usermsg(kg->irc, "otr keygen for %s/%s complete", kg->handle, kg->protocol);
+		}
+		g_free(kg->keyfile);
+		g_mutex_free(kg->mutex);
+		g_free(kg);
+		return FALSE; /* unregister timeout */
+	}
+
+	return TRUE;  /* still working, continue checking */
+}
+
+void yes_keygen(gpointer w, void *data)
+{
+	account_t *acc = (account_t *)data;
+	
+	otr_keygen(acc->irc, acc->user, acc->prpl->name);
+}
+
+void no_keygen(gpointer w, void *data)
+{
+	account_t *acc = (account_t *)data;
+	
+	irc_usermsg(acc->irc, "proceeding without key, otr inoperable on %s/%s",
+		acc->user, acc->prpl->name);
+}
+
+
+#else /* WITH_OTR undefined */
+
+void cmd_otr(irc_t *irc, char **args)
+{
+	irc_usermsg(irc, "otr: n/a, compiled without OTR support");
+}
+
+#endif