util/cbfstool/cbfs-mkpayload.c

   1 /*
   2  * cbfs-mkpayload
   3  *
   4  * Copyright (C) 2008 Jordan Crouse <jordan@cosmicpenguin.net>
   5  *               2009 coresystems GmbH
   6  *                 written by Patrick Georgi <patrick.georgi@coresystems.de>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; version 2 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
  20  */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26 #include "elf.h"
  27 #include <fcntl.h>
  28 #include <getopt.h>
  29 #include <sys/stat.h>
  30 #include <arpa/inet.h>
  31
  32 #include "common.h"
  33 #include "cbfs.h"
  34
  35 int parse_elf_to_payload(unsigned char *input, unsigned char **output,
  36                          comp_algo algo)
  37 {
  38         Elf32_Phdr *phdr;
  39         Elf32_Ehdr *ehdr;
  40         Elf32_Shdr *shdr;
  41         char *header;
  42         char *strtab;
  43         unsigned char *sptr;
  44         int headers;
  45         int segments = 1;
  46         int isize = 0, osize = 0;
  47         int doffset = 0;
  48         struct cbfs_payload_segment *segs;
  49         int i;
  50
  51         if(!iself(input)){
  52                 printf("Fatal error: the payload file is not in ELF format!\n");
  53                 exit(1);
  54         }
  55
  56
  57         comp_func_ptr compress = compression_function(algo);
  58         if (!compress)
  59                 return -1;
  60
  61         ehdr = (Elf32_Ehdr *) input;
  62         headers = ehdr->e_phnum;
  63         header = (char *)ehdr;
  64
  65         phdr = (Elf32_Phdr *) & (header[ehdr->e_phoff]);
  66         shdr = (Elf32_Shdr *) & (header[ehdr->e_shoff]);
  67
  68         strtab = &header[shdr[ehdr->e_shstrndx].sh_offset];
  69
  70         /* Count the number of headers - look for the .notes.pinfo
  71          * section */
  72
  73         for (i = 0; i < ehdr->e_shnum; i++) {
  74                 char *name;
  75
  76                 if (i == ehdr->e_shstrndx)
  77                         continue;
  78
  79                 if (shdr[i].sh_size == 0)
  80                         continue;
  81
  82                 name = (char *)(strtab + shdr[i].sh_name);
  83
  84                 if (!strcmp(name, ".note.pinfo")) {
  85                         segments++;
  86                         isize += (unsigned int)shdr[i].sh_size;
  87                 }
  88         }
  89
  90         /* Now, regular headers - we only care about PT_LOAD headers,
  91          * because thats what we're actually going to load
  92          */
  93
  94         for (i = 0; i < headers; i++) {
  95                 if (phdr[i].p_type != PT_LOAD)
  96                         continue;
  97
  98                 /* Empty segments are never interesting */
  99                 if (phdr[i].p_memsz == 0)
 100                         continue;
 101
 102                 isize += phdr[i].p_filesz;
 103
 104                 segments++;
 105         }
 106
 107         /* Allocate a block of memory to store the data in */
 108
 109         sptr =
 110             calloc((segments * sizeof(struct cbfs_payload_segment)) + isize, 1);
 111         doffset = (segments * sizeof(struct cbfs_payload_segment));
 112
 113         if (sptr == NULL)
 114                 goto err;
 115
 116         segs = (struct cbfs_payload_segment *)sptr;
 117         segments = 0;
 118
 119         for (i = 0; i < ehdr->e_shnum; i++) {
 120                 char *name;
 121
 122                 if (i == ehdr->e_shstrndx)
 123                         continue;
 124
 125                 if (shdr[i].sh_size == 0)
 126                         continue;
 127
 128                 name = (char *)(strtab + shdr[i].sh_name);
 129
 130                 if (!strcmp(name, ".note.pinfo")) {
 131                         segs[segments].type = PAYLOAD_SEGMENT_PARAMS;
 132                         segs[segments].load_addr = 0;
 133                         segs[segments].len = (unsigned int)shdr[i].sh_size;
 134                         segs[segments].offset = doffset;
 135
 136                         memcpy((unsigned long *)(sptr + doffset),
 137                                &header[shdr[i].sh_offset], shdr[i].sh_size);
 138
 139                         doffset += segs[segments].len;
 140                         osize += segs[segments].len;
 141
 142                         segments++;
 143                 }
 144         }
 145
 146         for (i = 0; i < headers; i++) {
 147                 if (phdr[i].p_type != PT_LOAD)
 148                         continue;
 149
 150                 if (phdr[i].p_memsz == 0)
 151                         continue;
 152
 153                 if (phdr[i].p_filesz == 0) {
 154                         segs[segments].type = PAYLOAD_SEGMENT_BSS;
 155                         segs[segments].load_addr =
 156                             (unsigned long long)htonl(phdr[i].p_paddr);
 157                         segs[segments].mem_len =
 158                             (unsigned int)htonl(phdr[i].p_memsz);
 159                         segs[segments].offset = htonl(doffset);
 160
 161                         segments++;
 162                         continue;
 163                 }
 164
 165                 segs[segments].type = PAYLOAD_SEGMENT_DATA;
 166                 segs[segments].load_addr = (unsigned int)htonl(phdr[i].p_paddr);
 167                 segs[segments].mem_len = (unsigned int)htonl(phdr[i].p_memsz);
 168                 segs[segments].compression = htonl(algo);
 169                 segs[segments].offset = htonl(doffset);
 170
 171                 int len;
 172                 compress((char *)&header[phdr[i].p_offset],
 173                          phdr[i].p_filesz, (char *)(sptr + doffset), &len);
 174                 segs[segments].len = htonl(len);
 175
 176                 /* If the compressed section is larger, then use the
 177                    original stuff */
 178
 179                 if ((unsigned int)len > phdr[i].p_filesz) {
 180                         segs[segments].compression = 0;
 181                         segs[segments].len = htonl(phdr[i].p_filesz);
 182
 183                         memcpy((char *)(sptr + doffset),
 184                                &header[phdr[i].p_offset], phdr[i].p_filesz);
 185                 }
 186
 187                 doffset += ntohl(segs[segments].len);
 188                 osize += ntohl(segs[segments].len);
 189
 190                 segments++;
 191         }
 192
 193         segs[segments].type = PAYLOAD_SEGMENT_ENTRY;
 194         segs[segments++].load_addr = (unsigned long long)htonl(ehdr->e_entry);
 195
 196         *output = sptr;
 197
 198         return (segments * sizeof(struct cbfs_payload_segment)) + osize;
 199
 200       err:
 201         return -1;
 202 }