pana_avp.c

00001 /*
00002  * Copyright (c) 2017-2018, Arm Limited and affiliates.
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 
00018 #include "nsconfig.h"
00019 #include "ns_types.h"
00020 #include "string.h"
00021 #include "common_functions.h"
00022 #include "Security/PANA/pana_avp.h"
00023 #ifdef PANA
00024 
00025 uint8_t *pana_avp_base_write(uint8_t avp_type, uint16_t length, uint8_t *dptr, uint16_t flags, uint32_t vendor_id)
00026 {
00027     dptr = common_write_16_bit(avp_type, dptr); //AVP Type
00028     dptr = common_write_16_bit(flags, dptr); //FLAGS
00029     dptr = common_write_16_bit(length, dptr); //LEN
00030     dptr = common_write_16_bit(0, dptr); //RESERVED
00031     if (flags & PANA_EAP_VENDOR_FLAG) {
00032         dptr = common_write_32_bit(vendor_id, dptr); //SET VENDOR
00033     }
00034     return dptr;
00035 }
00036 
00037 uint8_t *pana_avp_32_bit_write(uint8_t avp_type, uint32_t value, uint8_t *dptr)
00038 {
00039     dptr = pana_avp_base_write(avp_type, 4, dptr, 0, 0);
00040     return common_write_32_bit(value, dptr);
00041 }
00042 
00043 
00044 uint8_t *pana_avp_write_n_bytes(uint16_t avp_type, uint16_t length, const uint8_t *value, uint8_t *dptr)
00045 {
00046     dptr = pana_avp_base_write(avp_type, length, dptr, 0, 0);
00047     if (value) {
00048         memcpy(dptr, value, length);
00049     } else {
00050         memset(dptr, 0, length);
00051     }
00052     dptr += length;
00053     //Padding
00054     while (length % 4) {
00055         *dptr++ = 0;
00056         length++;
00057     }
00058     return  dptr;
00059 }
00060 
00061 uint8_t *pana_avp_vendor_id_write_n_bytes(uint16_t avp_type, uint16_t length, const uint8_t *value, uint8_t *dptr, uint32_t vendor_id)
00062 {
00063     dptr = pana_avp_base_write(avp_type, length, dptr, PANA_EAP_VENDOR_FLAG, vendor_id);
00064     if (value) {
00065         memcpy(dptr, value, length);
00066     } else {
00067         memset(dptr, 0, length);
00068     }
00069     dptr += length;
00070 
00071     while (length % 4) {
00072         *dptr++ = 0;
00073         length++;
00074     }
00075     return  dptr;
00076 
00077 }
00078 
00079 bool pana_avp_discover(uint8_t *dptr, uint16_t data_len, pana_avp_t *avp)
00080 {
00081     uint16_t avp_code;
00082     uint16_t readed = 0, pana_temp_var_16 = 0;
00083     avp->avp_ptr = NULL;
00084     while (readed  < data_len) {
00085         avp->flags = 0;
00086         avp->vendor_id = 0;
00087         avp_code = common_read_16_bit(dptr);
00088         dptr += 2;
00089         avp->flags = common_read_16_bit(dptr);
00090         dptr += 2;
00091         pana_temp_var_16 = common_read_16_bit(dptr);
00092         if (pana_temp_var_16 == 0) {
00093             return false;
00094         }
00095         dptr += 4; //Update pointer and Skip Reserved
00096         avp->len = pana_temp_var_16;
00097 
00098         if (avp->flags & PANA_EAP_VENDOR_FLAG) {
00099             avp->vendor_id = common_read_32_bit(dptr);
00100             dptr += 4;
00101             readed += 4;
00102         }
00103         readed += 8;
00104         readed += pana_temp_var_16;
00105         //Set Data Start here already
00106         avp->avp_ptr = dptr;
00107         dptr += pana_temp_var_16;
00108 
00109         //Check division remainder
00110         while (pana_temp_var_16 % 4) {
00111             dptr++;
00112             readed++;
00113             pana_temp_var_16++;
00114         }
00115 
00116         if (readed > data_len) {
00117             avp->avp_ptr = NULL;
00118             return false;
00119         }
00120 
00121         if (avp_code == avp->code) {
00122             //Save AVP pointer
00123             return true;
00124         }
00125         avp->avp_ptr = NULL;
00126 
00127     }
00128     return false;
00129 
00130 }
00131 #endif
00132