auth.c

oscar message protocol stack

/*
 * Family 0x0017 - Authentication.
 *
 * Deals with the authorizer for SNAC-based login, and also old-style 
 * non-SNAC login.
 *
 */

#define FAIM_INTERNAL
#include <aim.h>

#include "md5.h"

#include <ctype.h>

/**
 * Encode a password using old XOR method
 *
 * This takes a const pointer to a (null terminated) string
 * containing the unencoded password.  It also gets passed
 * an already allocated buffer to store the encoded password.
 * This buffer should be the exact length of the password without
 * the null.  The encoded password buffer /is not %NULL terminated/.
 *
 * The encoding_table seems to be a fixed set of values.  We'll
 * hope it doesn't change over time!  
 *
 * This is only used for the XOR method, not the better MD5 method.
 *
 * @param password Incoming password.
 * @param encoded Buffer to put encoded password.
 */
static int aim_encode_password(const char *password, fu8_t *encoded)
{
	fu8_t encoding_table[] = {
#if 0 /* old v1 table */
		0xf3, 0xb3, 0x6c, 0x99,
		0x95, 0x3f, 0xac, 0xb6,
		0xc5, 0xfa, 0x6b, 0x63,
		0x69, 0x6c, 0xc3, 0x9f
#else /* v2.1 table, also works for ICQ */
		0xf3, 0x26, 0x81, 0xc4,
		0x39, 0x86, 0xdb, 0x92,
		0x71, 0xa3, 0xb9, 0xe6,
		0x53, 0x7a, 0x95, 0x7c
#endif
	};
	unsigned int i;

	for (i = 0; i < strlen(password); i++)
		encoded[i] = (password[i] ^ encoding_table[i]);

	return 0;
}

#ifdef USE_OLD_MD5
static int aim_encode_password_md5(const char *password, const char *key, fu8_t *digest)
{
	md5_state_t state;

	md5_init(&state);	
	md5_append(&state, (const md5_byte_t *)key, strlen(key));
	md5_append(&state, (const md5_byte_t *)password, strlen(password));
	md5_append(&state, (const md5_byte_t *)AIM_MD5_STRING, strlen(AIM_MD5_STRING));
	md5_finish(&state, (md5_byte_t *)digest);

	return 0;
}
#else
static int aim_encode_password_md5(const char *password, const char *key, fu8_t *digest)
{
	md5_state_t state;
	fu8_t passdigest[16];

	md5_init(&state);
	md5_append(&state, (const md5_byte_t *)password, strlen(password));
	md5_finish(&state, (md5_byte_t *)&passdigest);

	md5_init(&state);	
	md5_append(&state, (const md5_byte_t *)key, strlen(key));
	md5_append(&state, (const md5_byte_t *)&passdigest, 16);
	md5_append(&state, (const md5_byte_t *)AIM_MD5_STRING, strlen(AIM_MD5_STRING));
	md5_finish(&state, (md5_byte_t *)digest);

	return 0;
}
#endif

/*
 * The FLAP version is sent by itself at the beginning of authorization 
 * connections.  The FLAP version is also sent before the cookie when connecting 
 * for other services (BOS, chatnav, chat, etc.).
 */
faim_export int aim_sendflapver(aim_session_t *sess, aim_conn_t *conn)
{
	aim_frame_t *fr;

	if (!(fr = aim_tx_new(sess, conn, AIM_FRAMETYPE_FLAP, 0x01, 4)))
		return -ENOMEM;

	aimbs_put32(&fr->data, 0x00000001);

	aim_tx_enqueue(sess, fr);

	return 0;
}

/*
 * This just pushes the passed cookie onto the passed connection, without
 * the SNAC header or any of that.
 *
 * Very commonly used, as every connection except auth will require this to
 * be the first thing you send.
 *
 */
faim_export int aim_sendcookie(aim_session_t *sess, aim_conn_t *conn, const fu16_t length, const fu8_t *chipsahoy)
{
	aim_frame_t *fr;
	aim_tlvlist_t *tl = NULL;

	if (!(fr = aim_tx_new(sess, conn, AIM_FRAMETYPE_FLAP, 0x0001, 4+2+2+length)))
		return -ENOMEM;

	aimbs_put32(&fr->data, 0x00000001);
	aim_tlvlist_add_raw(&tl, 0x0006, length, chipsahoy);
	aim_tlvlist_write(&fr->data, &tl);
	aim_tlvlist_free(&tl);

	aim_tx_enqueue(sess, fr);

	return 0;
}

/*
 * Part two of the ICQ hack.  Note the ignoring of the key.
 */
static int goddamnicq2(aim_session_t *sess, aim_conn_t *conn, const char *sn, const char *password, struct client_info_s *ci)
{
	aim_frame_t *fr;
	aim_tlvlist_t *tl = NULL;
	int passwdlen;
	fu8_t *password_encoded;

	passwdlen = strlen(password);
	if (!(password_encoded = (char *)malloc(passwdlen+1)))
		return -ENOMEM;
	if (passwdlen > MAXICQPASSLEN)
		passwdlen = MAXICQPASSLEN;

	if (!(fr = aim_tx_new(sess, conn, AIM_FRAMETYPE_FLAP, 0x01, 1152))) {
		free(password_encoded);
		return -ENOMEM;
	}

	aim_encode_password(password, password_encoded);

	aimbs_put32(&fr->data, 0x00000001); /* FLAP Version */
	aim_tlvlist_add_raw(&tl, 0x0001, strlen(sn), sn);
	aim_tlvlist_add_raw(&tl, 0x0002, passwdlen, password_encoded);

	if (ci->clientstring)
		aim_tlvlist_add_raw(&tl, 0x0003, strlen(ci->clientstring), ci->clientstring);
	aim_tlvlist_add_16(&tl, 0x0016, (fu16_t)ci->clientid);
	aim_tlvlist_add_16(&tl, 0x0017, (fu16_t)ci->major);
	aim_tlvlist_add_16(&tl, 0x0018, (fu16_t)ci->minor);
	aim_tlvlist_add_16(&tl, 0x0019, (fu16_t)ci->point);
	aim_tlvlist_add_16(&tl, 0x001a, (fu16_t)ci->build);
	aim_tlvlist_add_32(&tl, 0x0014, (fu32_t)ci->distrib); /* distribution chan */
	aim_tlvlist_add_raw(&tl, 0x000f, strlen(ci->lang), ci->lang);
	aim_tlvlist_add_raw(&tl, 0x000e, strlen(ci->country), ci->country);

	aim_tlvlist_write(&fr->data, &tl);

	free(password_encoded);
	aim_tlvlist_free(&tl);

	aim_tx_enqueue(sess, fr);

	return 0;
}

/*
 * Subtype 0x0002
 *
 * This is the initial login request packet.
 *
 * NOTE!! If you want/need to make use of the aim_sendmemblock() function,
 * then the client information you send here must exactly match the
 * executable that you're pulling the data from.
 *
 * Java AIM 1.1.19:
 *   clientstring = "AOL Instant Messenger (TM) version 1.1.19 for Java built 03/24/98, freeMem 215871 totalMem 1048567, i686, Linus, #2 SMP Sun Feb 11 03:41:17 UTC 2001 2.4.1-ac9, IBM Corporation, 1.1.8, 45.3, Tue Mar 27 12:09:17 PST 2001"
 *   clientid = 0x0001
 *   major  = 0x0001
 *   minor  = 0x0001
 *   point = (not sent)
 *   build  = 0x0013
 *   unknown= (not sent)
 *   
 * AIM for Linux 1.1.112:
 *   clientstring = "AOL Instant Messenger (SM)"
 *   clientid = 0x1d09
 *   major  = 0x0001
 *   minor  = 0x0001
 *   point = 0x0001
 *   build  = 0x0070
 *   unknown= 0x0000008b
 *   serverstore = 0x01
 *
 */
faim_export int aim_send_login(aim_session_t *sess, aim_conn_t *conn, const char *sn, const char *password, struct client_info_s *ci, const char *key)
{
	aim_frame_t *fr;
	aim_tlvlist_t *tl = NULL;
	fu8_t digest[16];
	aim_snacid_t snacid;

	if (!ci || !sn || !password)
		return -EINVAL;

	/* If we're signing on an ICQ account then use the older, XOR login method */
	if (isdigit(sn[0]))
		return goddamnicq2(sess, conn, sn, password, ci);

	if (!(fr = aim_tx_new(sess, conn, AIM_FRAMETYPE_FLAP, 0x02, 1152)))
		return -ENOMEM;

	snacid = aim_cachesnac(sess, 0x0017, 0x0002, 0x0000, NULL, 0);
	aim_putsnac(&fr->data, 0x0017, 0x0002, 0x0000, snacid);

	aim_tlvlist_add_raw(&tl, 0x0001, strlen(sn), sn);

	aim_encode_password_md5(password, key, digest);
	aim_tlvlist_add_raw(&tl, 0x0025, 16, digest);

#ifndef USE_OLD_MD5
	aim_tlvlist_add_noval(&tl, 0x004c);
#endif

	if (ci->clientstring)
		aim_tlvlist_add_raw(&tl, 0x0003, strlen(ci->clientstring), ci->clientstring);
	aim_tlvlist_add_16(&tl, 0x0016, (fu16_t)ci->clientid);
	aim_tlvlist_add_16(&tl, 0x0017, (fu16_t)ci->major);
	aim_tlvlist_add_16(&tl, 0x0018, (fu16_t)ci->minor);
	aim_tlvlist_add_16(&tl, 0x0019, (fu16_t)ci->point);
	aim_tlvlist_add_16(&tl, 0x001a, (fu16_t)ci->build);
	aim_tlvlist_add_32(&tl, 0x0014, (fu32_t)ci->distrib);
	aim_tlvlist_add_raw(&tl, 0x000f, strlen(ci->lang), ci->lang);
	aim_tlvlist_add_raw(&tl, 0x000e, strlen(ci->country), ci->country);

#ifndef NOSSI
	/*
	 * If set, old-fashioned buddy lists will not work. You will need
	 * to use SSI.
	 */
	aim_tlvlist_add_8(&tl, 0x004a, 0x01);
#endif

	aim_tlvlist_write(&fr->data, &tl);

	aim_tlvlist_free(&tl);
	
	aim_tx_enqueue(sess, fr);

	return 0;
}

/*
 * This is sent back as a general response to the login command.
 * It can be either an error or a success, depending on the
 * precense of certain TLVs.  
 *
 * The client should check the value passed as errorcode. If
 * its nonzero, there was an error.
 */
static int parse(aim_session_t *sess, aim_module_t *mod, aim_frame_t *rx, aim_modsnac_t *snac, aim_bstream_t *bs)
{
	aim_tlvlist_t *tlvlist;
	aim_rxcallback_t userfunc;
	struct aim_authresp_info *info;