git.zerfleddert.de Git - hmcfgusb/blob - firmware.c

   1 /* generic firmware-functions for HomeMatic
   2  *
   3  * Copyright (c) 2014 Michael Gernoth <michael@gernoth.net>
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy
   6  * of this software and associated documentation files (the "Software"), to
   7  * deal in the Software without restriction, including without limitation the
   8  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
   9  * sell copies of the Software, and to permit persons to whom the Software is
  10  * furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <unistd.h>
  27 #include <stdint.h>
  28 #include <string.h>
  29 #include <strings.h>
  30 #include <errno.h>
  31 #include <sys/types.h>
  32 #include <sys/stat.h>
  33 #include <fcntl.h>
  34 #include <sys/time.h>
  35
  36 #include "util.h"
  37 #include "firmware.h"
  38
  39 /* This might be wrong, but it works for current fw */
  40 #define MAX_BLOCK_LENGTH        512
  41
  42 struct firmware* firmware_read_firmware(char *filename, int debug)
  43 {
  44         struct firmware *fw;
  45         struct stat stat_buf;
  46         uint8_t buf[4096];
  47         uint16_t len;
  48         int fd;
  49         int r;
  50         int i;
  51
  52         fw = malloc(sizeof(struct firmware));
  53         if (!fw) {
  54                 perror("malloc(fw)");
  55                 return NULL;
  56         }
  57
  58         memset(fw, 0, sizeof(struct firmware));
  59
  60         if (stat(filename, &stat_buf) == -1) {
  61                 fprintf(stderr, "Can't stat %s: %s\n", filename, strerror(errno));
  62                 exit(EXIT_FAILURE);
  63         }
  64
  65         fd = open(filename, O_RDONLY);
  66         if (fd < 0) {
  67                 fprintf(stderr, "Can't open %s: %s", filename, strerror(errno));
  68                 exit(EXIT_FAILURE);
  69         }
  70
  71         printf("Reading firmware from %s...\n", filename);
  72         do {
  73                 memset(buf, 0, sizeof(buf));
  74                 r = read(fd, buf, 4);
  75                 if (r < 0) {
  76                         perror("read");
  77                         exit(EXIT_FAILURE);
  78                 } else if (r == 0) {
  79                         break;
  80                 } else if (r != 4) {
  81                         printf("can't get length information!\n");
  82                         exit(EXIT_FAILURE);
  83                 }
  84
  85                 for (i = 0; i < r; i++) {
  86                         if (!validate_nibble(buf[i])) {
  87                                 fprintf(stderr, "Firmware file not valid!\n");
  88                                 exit(EXIT_FAILURE);
  89                         }
  90                 }
  91
  92                 len = (ascii_to_nibble(buf[0]) & 0xf)<< 4;
  93                 len |= ascii_to_nibble(buf[1]) & 0xf;
  94                 len <<= 8;
  95                 len |= (ascii_to_nibble(buf[2]) & 0xf)<< 4;
  96                 len |= ascii_to_nibble(buf[3]) & 0xf;
  97
  98                 if (len > MAX_BLOCK_LENGTH) {
  99                         fprintf(stderr, "Invalid block-length %u > %u for block %d!\n", len, MAX_BLOCK_LENGTH, fw->fw_blocks+1);
 100                         exit(EXIT_FAILURE);
 101                 }
 102
 103                 fw->fw = realloc(fw->fw, sizeof(uint8_t*) * (fw->fw_blocks + 1));
 104                 if (fw->fw == NULL) {
 105                         perror("Can't reallocate fw->fw-blocklist");
 106                         exit(EXIT_FAILURE);
 107                 }
 108
 109                 fw->fw[fw->fw_blocks] = malloc(len + 4);
 110                 if (fw->fw[fw->fw_blocks] == NULL) {
 111                         perror("Can't allocate memory for fw->fw-block");
 112                         exit(EXIT_FAILURE);
 113                 }
 114
 115                 fw->fw[fw->fw_blocks][0] = (fw->fw_blocks >> 8) & 0xff;
 116                 fw->fw[fw->fw_blocks][1] = fw->fw_blocks & 0xff;
 117                 fw->fw[fw->fw_blocks][2] = (len >> 8) & 0xff;
 118                 fw->fw[fw->fw_blocks][3] = len & 0xff;
 119
 120                 r = read(fd, buf, len * 2);
 121                 if (r < 0) {
 122                         perror("read");
 123                         exit(EXIT_FAILURE);
 124                 } else if (r < len * 2) {
 125                         fprintf(stderr, "short read, aborting (%d < %d)\n", r, len * 2);
 126                         exit(EXIT_FAILURE);
 127                 }
 128
 129                 for (i = 0; i < r; i+=2) {
 130                         if ((!validate_nibble(buf[i])) ||
 131                             (!validate_nibble(buf[i+1]))) {
 132                                 fprintf(stderr, "Firmware file not valid!\n");
 133                                 exit(EXIT_FAILURE);
 134                         }
 135
 136                         fw->fw[fw->fw_blocks][(i/2) + 4] = (ascii_to_nibble(buf[i]) & 0xf)<< 4;
 137                         fw->fw[fw->fw_blocks][(i/2) + 4] |= ascii_to_nibble(buf[i+1]) & 0xf;
 138                 }
 139
 140                 fw->fw_blocks++;
 141                 if (debug)
 142                         printf("Firmware block %d with length %u read.\n", fw->fw_blocks, len);
 143         } while(r > 0);
 144
 145         if (fw->fw_blocks == 0) {
 146                 fprintf(stderr, "Firmware file not valid!\n");
 147                 exit(EXIT_FAILURE);
 148         }
 149
 150         printf("Firmware with %d blocks successfully read.\n", fw->fw_blocks);
 151
 152         return fw;
 153 }
 154
 155 void firmware_free(struct firmware *fw)
 156 {
 157         int i;
 158
 159         for (i = 0; i < fw->fw_blocks; i++)
 160                 free(fw->fw[i]);
 161
 162         free(fw->fw);
 163         free(fw);
 164 }