view src/g23m-fad/udp/udp_kerf.c @ 220:0ed36de51973

ABB semaphore protection overhaul The ABB semaphone protection logic that came with TCS211 from TI was broken in several ways: * Some semaphore-protected functions were called from Application_Initialize() context. NU_Obtain_Semaphore() called with NU_SUSPEND fails with NU_INVALID_SUSPEND in this context, but the return value wasn't checked, and NU_Release_Semaphore() would be called unconditionally at the end. The latter call would increment the semaphore count past 1, making the semaphore no longer binary and thus no longer effective for resource protection. The fix is to check the return value from NU_Obtain_Semaphore() and skip the NU_Release_Semaphore() call if the semaphore wasn't properly obtained. * Some SPI hardware manipulation was being done before entering the semaphore- protected critical section. The fix is to reorder the code: first obtain the semaphore, then do everything else. * In the corner case of L1/DSP recovery, l1_abb_power_on() would call some non-semaphore-protected ABB & SPI init functions. The fix is to skip those calls in the case of recovery. * A few additional corner cases existed, all of which are fixed by making ABB semaphore protection 100% consistent for all ABB functions and code paths. There is still one remaining problem of priority inversion: suppose a low- priority task calls an ABB function, and some medium-priority task just happens to preempt right in the middle of that semaphore-protected ABB operation. Then the high-priority SPI task is locked out for a non-deterministic time until that medium-priority task finishes its work and goes back to sleep. This priority inversion problem remains outstanding for now.
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 26 Apr 2021 20:55:25 +0000
parents fa8dc04885d8
children
line wrap: on
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/*
+----------------------------------------------------------------------------
|  Project :
|  Modul   :
+----------------------------------------------------------------------------
|  Copyright 2002 Texas Instruments Berlin, AG
|                 All rights reserved.
|
|                 This file is confidential and a trade secret of Texas
|                 Instruments Berlin, AG
|                 The receipt of or possession of this file does not convey
|                 any rights to reproduce or disclose its contents or to
|                 manufacture, use, or sell anything it may describe, in
|                 whole, or in part, without the specific written consent of
|                 Texas Instruments Berlin, AG.
+----------------------------------------------------------------------------
|  Purpose :  This Modul defines the functions for processing
|             of incomming primitives for the component
|             Internet Protocol of the mobile station
+----------------------------------------------------------------------------
*/

#define ENTITY_UDP

#include <string.h>
#include "typedefs.h"
#include "pcm.h"
#include "pconst.cdg"
#include "mconst.cdg"
#include "message.h"
#include "ccdapi.h"
#include "vsi.h"
#include "macdef.h" /* to get PFREE_DESC2 */
#include "custom.h"
#include "gsm.h"
#include "prim.h"
#include "cus_udp.h"
#include "cnf_udp.h"
#include "mon_udp.h"
#include "pei.h"
#include "tok.h"
#include "dti.h" /* to get dti lib */
#include "udp.h"
#include "ip_udp.h"

/*
+--------------------------------------------------------------------+
| PROJECT : WAP                                 MODULE  : udp_kerf.c |
| STATE   : code                                ROUTINE : init_udp   |
+--------------------------------------------------------------------+

  PURPOSE : Init the global variables of UDP
*/

void init_udp (void)
{
  T_HILA * p_ul;
  T_LOLA * p_dl;
  T_KER * p_ker = & udp_data->ker;

  /* Set global variables for every entity */

  INIT_STATE (HILA, DOWN);
  INIT_STATE (LOLA, DOWN);

  p_ul = & udp_data->hila;
  *p_ul->entity_name = 0;
  p_ul->dti_state    = DTI_CLOSED;
  p_ul->dti_data_req = NULL;

  p_dl = & udp_data->lola;
  *p_dl->entity_name = 0;
  p_dl->dti_state    = DTI_CLOSED;
  p_dl->dti_data_ind = NULL;
  p_dl->drop_packet  = FALSE;
  p_dl->state_err    = STATE_DL_NO_ERROR;
  p_dl->src_addr     = NO_ADDR;
  p_dl->dst_addr     = NO_ADDR;
  p_dl->dst_port     = NO_PORT;
  p_dl->src_port     = NO_PORT;

  /* Downlink and uplink for one entity */

  p_ker->send_icmp         = FALSE;
  p_ker->port_state        = PORT_DOWN;
  p_ker->dti_data_req_icmp = NULL;

  p_ker->dst_addr = NO_ADDR;
  p_ker->src_addr = NO_ADDR;
  p_ker->src_port = NO_PORT;
  p_ker->dst_port = NO_PORT;
}

/*
+--------------------------------------------------------------------+
| PROJECT : WAP                           MODULE  : udp_kerf.c       |
| STATE   : code                          ROUTINE : udp_build_packet |
+--------------------------------------------------------------------+

  PURPOSE : Build UDP and ICMP packets to send
*/

void udp_build_packet (BOOL hila, UBYTE to_do)
{
  T_KER * p_ker = & udp_data->ker;

  if (hila) /* Build the packets for higher layer */
  {
    switch (to_do)
    {
    case B_NORMAL_PACKET:
      {
        T_desc_list2 * desc_list = & udp_data->hila.dti_data_req->desc_list2;
        T_desc2 * desc = (T_desc2 *) desc_list->first;
        USHORT udp_payload_len = desc_list->list_len;

        if (desc == NULL)
        {
          TRACE_ERROR ("Hila's desc == NULL in udp_build_packet().");
          return;
        }
        else
        {
          /* Make a new desc for the IP and UDP packet header */

          USHORT headroom = LEN_IP_HEADER_B + LEN_UDP_HEADER_B;
          UBYTE * ip_header;
          T_desc2 * desc_new = M_ALLOC (offsetof (T_desc2, buffer) + headroom);

          if (desc_new == NULL)
          {
            TRACE_ERROR ("Not enough memory in udp_build_packet().");
            return;
          }
          desc_new->next = (ULONG) desc;
          desc_new->offset = 0;
          desc_new->len = headroom;
          desc_new->size = headroom;
          ip_header = desc_new->buffer;
          {
            register unsigned i;
            for (i=0; i < headroom; i++)
              ip_header[i] = '\0';/*lint !e661 !e662 (Warning -- access/creation of out-of-bounds pointer) */
          }

          /* Put the desc at the first place of the descs and
           * build the UDP header */

          desc_list->first = (ULONG) desc_new;
          desc_list->list_len = (USHORT) (desc_new->len + desc_list->list_len);

          /* Fill in IP header information */

          SET_IP_VERSION (ip_header, IP_VERSION);
          SET_IP_HEADER_LEN (ip_header, MIN_HEADER_LEN);
          /*lint -e{661, 662} (Warning -- access/creation of out-of-bounds pointer) */
         {
          SET_IP_TOTAL_LEN (ip_header, desc_list->list_len);
          SET_IP_PROT (ip_header, UDP_PROT);
          SET_IP_SOURCE_ADDR (ip_header, p_ker->src_addr);
          SET_IP_DEST_ADDR (ip_header, p_ker->dst_addr);

          SET_UDP_SRC_PORT (ip_header, p_ker->src_port);
          SET_UDP_DST_PORT (ip_header, p_ker->dst_port);
          SET_UDP_LEN (ip_header, udp_payload_len + LEN_UDP_HEADER_B);
          }
          {
            UBYTE pseudo_header [LEN_PSEUDO_HEADER_B];
            ULONG overlay;
            USHORT chksum;

            /* Build the pseudoheader for to calculate the chksum */

            SET_UDP_PSEUDO_H_SRC_ADDR (pseudo_header, p_ker->src_addr);
            SET_UDP_PSEUDO_H_DEST_ADDR (pseudo_header, p_ker->dst_addr);
            SET_UDP_PSEUDO_H_ZERO (pseudo_header, 0);
            SET_UDP_PSEUDO_H_PROT (pseudo_header, UDP_PROT);
            SET_UDP_PSEUDO_H_LEN (pseudo_header, udp_payload_len + LEN_UDP_HEADER_B);

            /* Calculate the checksum for the pseudoheader */
            overlay = partial_checksum (pseudo_header, LEN_PSEUDO_HEADER_B);

            /* Calculate for the UDP header and the data */
            RESET_UDP_CHKSUM (ip_header, LEN_IP_HEADER_B);/*lint !e661 !e662 (Warning -- access/creation of out-of-bounds pointer) */
            chksum = desc_checksum (desc_list, LEN_IP_HEADER_B, overlay);
            SET_UDP_CHKSUM (ip_header, LEN_IP_HEADER_B, chksum);/*lint !e661 !e662 (Warning -- access/creation of out-of-bounds pointer) */
          }
        }
      }
      break;

    default:
      break;
    }
  }
  else /* Build the packets for lower layer */
  {
    T_LOLA * p_dl = & udp_data->lola;
    T_desc_list2 * desc_list = & p_dl->dti_data_ind->desc_list2;
    T_desc2 * desc = (T_desc2 *) desc_list->first;

    if (desc == NULL)
    {
      TRACE_ERROR ("Lola's desc == NULL in udp_build_packet().");
      return;
    }
    if (desc->len < LEN_IP_HEADER_B)
    {
      TRACE_ERROR (
        "Lola's desc->len < LEN_IP_HEADER_B "
        "in udp_build_packet()."
      );
      return;
    }
    if (GET_IP_HEADER_LEN_B (desc->buffer + desc->offset) < LEN_IP_HEADER_B)
    {
      TRACE_ERROR (
        "Lola's GET_IP_HEADER_LEN_B() < LEN_IP_HEADER_B "
        "in udp_build_packet()."
      );
      return;
    }

    switch (to_do)
    {
    case B_NORMAL_PACKET:
      {
        /* Build a new desc for IP addresses and port numbers */

        T_desc2 * addr = M_ALLOC (
          offsetof (T_desc2, buffer) + sizeof (T_SRC_DES)
        );
        if (addr == NULL) {
          TRACE_ERROR ("Not enough memory in udp_build_packet().");
          return;
        }

        addr->next = (ULONG) desc;
        addr->offset = 0;
        addr->len = sizeof (T_SRC_DES);
        addr->size = sizeof (T_SRC_DES);

        memcpy (((T_SRC_DES *) addr->buffer)->src_ip, & p_dl->src_addr, 4);
        memcpy (((T_SRC_DES *) addr->buffer)->des_ip, & p_dl->dst_addr, 4);
        memcpy (((T_SRC_DES *) addr->buffer)->src_port, & p_dl->src_port, 2);
        memcpy (((T_SRC_DES *) addr->buffer)->des_port, & p_dl->dst_port, 2);

        desc_list->first = (ULONG) addr;
        desc_list->list_len = (USHORT) (addr->len + desc_list->list_len);

        /* Filter out the given IP and UDP header */
        {
          register unsigned headroom =
            GET_IP_HEADER_LEN_B (desc->buffer + desc->offset) + LEN_UDP_HEADER_B;
          if (desc->len < headroom)
          {
            TRACE_ERROR ("Lola's IP packet is short in udp_build_packet().");
            return;
          }
          memmove (
            desc->buffer + desc->offset,
            desc->buffer + desc->offset + headroom,
            desc->len - headroom
          );
          desc->len = (USHORT) (desc->len - headroom);
          desc_list->list_len = (USHORT) (desc_list->list_len - headroom);
        }
      }
      break;

    case B_NO_DEST_PORT:
      {
        /* We build the whole ICMP packet */

        PPASS (p_dl->dti_data_ind, data_req, DTI2_DATA_REQ);

        desc_list = & data_req->desc_list2;
        desc = (T_desc2 *) desc_list->first;

        build_icmp_with_payload (
          data_req,
          IDENTITY_0,
          STANDARD_TTL,
          GET_IP_DEST_ADDR (desc->buffer + desc->offset),
          ICMP_TYP_DEST_URECHBL,
          ICMP_CODE_NO_PORT
        );

        p_ker->dti_data_req_icmp = data_req;
      }
      break;

    default:
      break;
    }
  }
}

/*-------------------------------------------------------------------------*/