static int ccp_ackci()

in net/ip/lwip_base/src/netif/ppp/ccp.c [835:922]

• 80 lines of code
• 40 McCabe index (conditional complexity)

static int ccp_ackci(fsm *f, u_char *p, int len) {
    ppp_pcb *pcb = f->pcb;
    ccp_options *go = &pcb->ccp_gotoptions;
#if BSDCOMPRESS_SUPPORT || PREDICTOR_SUPPORT
    u_char *p0 = p;
#endif /* BSDCOMPRESS_SUPPORT || PREDICTOR_SUPPORT */

#if MPPE_SUPPORT
    if (go->mppe) {
	u_char opt_buf[CILEN_MPPE];

	opt_buf[0] = CI_MPPE;
	opt_buf[1] = CILEN_MPPE;
	MPPE_OPTS_TO_CI(go->mppe, &opt_buf[2]);
	if (len < CILEN_MPPE || memcmp(opt_buf, p, CILEN_MPPE))
	    return 0;
	p += CILEN_MPPE;
	len -= CILEN_MPPE;
	/* XXX Cope with first/fast ack */
	if (len == 0)
	    return 1;
    }
#endif /* MPPE_SUPPORT */
#if DEFLATE_SUPPORT
    if (go->deflate) {
	if (len < CILEN_DEFLATE
	    || p[0] != (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT)
	    || p[1] != CILEN_DEFLATE
	    || p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
	    || p[3] != DEFLATE_CHK_SEQUENCE)
	    return 0;
	p += CILEN_DEFLATE;
	len -= CILEN_DEFLATE;
	/* XXX Cope with first/fast ack */
	if (len == 0)
	    return 1;
	if (go->deflate_correct && go->deflate_draft) {
	    if (len < CILEN_DEFLATE
		|| p[0] != CI_DEFLATE_DRAFT
		|| p[1] != CILEN_DEFLATE
		|| p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
		|| p[3] != DEFLATE_CHK_SEQUENCE)
		return 0;
	    p += CILEN_DEFLATE;
	    len -= CILEN_DEFLATE;
	}
    }
#endif /* DEFLATE_SUPPORT */
#if BSDCOMPRESS_SUPPORT
    if (go->bsd_compress) {
	if (len < CILEN_BSD_COMPRESS
	    || p[0] != CI_BSD_COMPRESS || p[1] != CILEN_BSD_COMPRESS
	    || p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits))
	    return 0;
	p += CILEN_BSD_COMPRESS;
	len -= CILEN_BSD_COMPRESS;
	/* XXX Cope with first/fast ack */
	if (p == p0 && len == 0)
	    return 1;
    }
#endif /* BSDCOMPRESS_SUPPORT */
#if PREDICTOR_SUPPORT
    if (go->predictor_1) {
	if (len < CILEN_PREDICTOR_1
	    || p[0] != CI_PREDICTOR_1 || p[1] != CILEN_PREDICTOR_1)
	    return 0;
	p += CILEN_PREDICTOR_1;
	len -= CILEN_PREDICTOR_1;
	/* XXX Cope with first/fast ack */
	if (p == p0 && len == 0)
	    return 1;
    }
    if (go->predictor_2) {
	if (len < CILEN_PREDICTOR_2
	    || p[0] != CI_PREDICTOR_2 || p[1] != CILEN_PREDICTOR_2)
	    return 0;
	p += CILEN_PREDICTOR_2;
	len -= CILEN_PREDICTOR_2;
	/* XXX Cope with first/fast ack */
	if (p == p0 && len == 0)
	    return 1;
    }
#endif /* PREDICTOR_SUPPORT */

    if (len != 0)
	return 0;
    return 1;
}