LXR qemu/hw/elf

   1static void glue(bswap_ehdr, SZ)(struct elfhdr *ehdr)
   2{
   3    bswap16s(&ehdr->e_type);                    /* Object file type */
   4    bswap16s(&ehdr->e_machine);         /* Architecture */
   5    bswap32s(&ehdr->e_version);         /* Object file version */
   6    bswapSZs(&ehdr->e_entry);           /* Entry point virtual address */
   7    bswapSZs(&ehdr->e_phoff);           /* Program header table file offset */
   8    bswapSZs(&ehdr->e_shoff);           /* Section header table file offset */
   9    bswap32s(&ehdr->e_flags);           /* Processor-specific flags */
  10    bswap16s(&ehdr->e_ehsize);          /* ELF header size in bytes */
  11    bswap16s(&ehdr->e_phentsize);               /* Program header table entry size */
  12    bswap16s(&ehdr->e_phnum);           /* Program header table entry count */
  13    bswap16s(&ehdr->e_shentsize);               /* Section header table entry size */
  14    bswap16s(&ehdr->e_shnum);           /* Section header table entry count */
  15    bswap16s(&ehdr->e_shstrndx);                /* Section header string table index */
  16}
  17
  18static void glue(bswap_phdr, SZ)(struct elf_phdr *phdr)
  19{
  20    bswap32s(&phdr->p_type);                    /* Segment type */
  21    bswapSZs(&phdr->p_offset);          /* Segment file offset */
  22    bswapSZs(&phdr->p_vaddr);           /* Segment virtual address */
  23    bswapSZs(&phdr->p_paddr);           /* Segment physical address */
  24    bswapSZs(&phdr->p_filesz);          /* Segment size in file */
  25    bswapSZs(&phdr->p_memsz);           /* Segment size in memory */
  26    bswap32s(&phdr->p_flags);           /* Segment flags */
  27    bswapSZs(&phdr->p_align);           /* Segment alignment */
  28}
  29
  30static void glue(bswap_shdr, SZ)(struct elf_shdr *shdr)
  31{
  32    bswap32s(&shdr->sh_name);
  33    bswap32s(&shdr->sh_type);
  34    bswapSZs(&shdr->sh_flags);
  35    bswapSZs(&shdr->sh_addr);
  36    bswapSZs(&shdr->sh_offset);
  37    bswapSZs(&shdr->sh_size);
  38    bswap32s(&shdr->sh_link);
  39    bswap32s(&shdr->sh_info);
  40    bswapSZs(&shdr->sh_addralign);
  41    bswapSZs(&shdr->sh_entsize);
  42}
  43
  44static void glue(bswap_sym, SZ)(struct elf_sym *sym)
  45{
  46    bswap32s(&sym->st_name);
  47    bswapSZs(&sym->st_value);
  48    bswapSZs(&sym->st_size);
  49    bswap16s(&sym->st_shndx);
  50}
  51
  52static struct elf_shdr *glue(find_section, SZ)(struct elf_shdr *shdr_table,
  53                                               int n, int type)
  54{
  55    int i;
  56    for(i=0;i<n;i++) {
  57        if (shdr_table[i].sh_type == type)
  58            return shdr_table + i;
  59    }
  60    return NULL;
  61}
  62
  63static int glue(symfind, SZ)(const void *s0, const void *s1)
  64{
  65    hwaddr addr = *(hwaddr *)s0;
  66    struct elf_sym *sym = (struct elf_sym *)s1;
  67    int result = 0;
  68    if (addr < sym->st_value) {
  69        result = -1;
  70    } else if (addr >= sym->st_value + sym->st_size) {
  71        result = 1;
  72    }
  73    return result;
  74}
  75
  76static const char *glue(lookup_symbol, SZ)(struct syminfo *s,
  77                                           hwaddr orig_addr)
  78{
  79    struct elf_sym *syms = glue(s->disas_symtab.elf, SZ);
  80    struct elf_sym *sym;
  81
  82    sym = bsearch(&orig_addr, syms, s->disas_num_syms, sizeof(*syms),
  83                  glue(symfind, SZ));
  84    if (sym != NULL) {
  85        return s->disas_strtab + sym->st_name;
  86    }
  87
  88    return "";
  89}
  90
  91static int glue(symcmp, SZ)(const void *s0, const void *s1)
  92{
  93    struct elf_sym *sym0 = (struct elf_sym *)s0;
  94    struct elf_sym *sym1 = (struct elf_sym *)s1;
  95    return (sym0->st_value < sym1->st_value)
  96        ? -1
  97        : ((sym0->st_value > sym1->st_value) ? 1 : 0);
  98}
  99
 100static int glue(load_symbols, SZ)(struct elfhdr *ehdr, int fd, int must_swab,
 101                                  int clear_lsb)
 102{
 103    struct elf_shdr *symtab, *strtab, *shdr_table = NULL;
 104    struct elf_sym *syms = NULL;
 105    struct syminfo *s;
 106    int nsyms, i;
 107    char *str = NULL;
 108
 109    shdr_table = load_at(fd, ehdr->e_shoff,
 110                         sizeof(struct elf_shdr) * ehdr->e_shnum);
 111    if (!shdr_table)
 112        return -1;
 113
 114    if (must_swab) {
 115        for (i = 0; i < ehdr->e_shnum; i++) {
 116            glue(bswap_shdr, SZ)(shdr_table + i);
 117        }
 118    }
 119
 120    symtab = glue(find_section, SZ)(shdr_table, ehdr->e_shnum, SHT_SYMTAB);
 121    if (!symtab)
 122        goto fail;
 123    syms = load_at(fd, symtab->sh_offset, symtab->sh_size);
 124    if (!syms)
 125        goto fail;
 126
 127    nsyms = symtab->sh_size / sizeof(struct elf_sym);
 128
 129    i = 0;
 130    while (i < nsyms) {
 131        if (must_swab)
 132            glue(bswap_sym, SZ)(&syms[i]);
 133        /* We are only interested in function symbols.
 134           Throw everything else away.  */
 135        if (syms[i].st_shndx == SHN_UNDEF ||
 136                syms[i].st_shndx >= SHN_LORESERVE ||
 137                ELF_ST_TYPE(syms[i].st_info) != STT_FUNC) {
 138            nsyms--;
 139            if (i < nsyms) {
 140                syms[i] = syms[nsyms];
 141            }
 142            continue;
 143        }
 144        if (clear_lsb) {
 145            /* The bottom address bit marks a Thumb or MIPS16 symbol.  */
 146            syms[i].st_value &= ~(glue(glue(Elf, SZ), _Addr))1;
 147        }
 148        i++;
 149    }
 150    if (nsyms) {
 151        syms = g_realloc(syms, nsyms * sizeof(*syms));
 152
 153        qsort(syms, nsyms, sizeof(*syms), glue(symcmp, SZ));
 154        for (i = 0; i < nsyms - 1; i++) {
 155            if (syms[i].st_size == 0) {
 156                syms[i].st_size = syms[i + 1].st_value - syms[i].st_value;
 157            }
 158        }
 159    } else {
 160        g_free(syms);
 161        syms = NULL;
 162    }
 163
 164    /* String table */
 165    if (symtab->sh_link >= ehdr->e_shnum)
 166        goto fail;
 167    strtab = &shdr_table[symtab->sh_link];
 168
 169    str = load_at(fd, strtab->sh_offset, strtab->sh_size);
 170    if (!str)
 171        goto fail;
 172
 173    /* Commit */
 174    s = g_malloc0(sizeof(*s));
 175    s->lookup_symbol = glue(lookup_symbol, SZ);
 176    glue(s->disas_symtab.elf, SZ) = syms;
 177    s->disas_num_syms = nsyms;
 178    s->disas_strtab = str;
 179    s->next = syminfos;
 180    syminfos = s;
 181    g_free(shdr_table);
 182    return 0;
 183 fail:
 184    g_free(syms);
 185    g_free(str);
 186    g_free(shdr_table);
 187    return -1;
 188}
 189
 190static int glue(load_elf, SZ)(const char *name, int fd,
 191                              uint64_t (*translate_fn)(void *, uint64_t),
 192                              void *translate_opaque,
 193                              int must_swab, uint64_t *pentry,
 194                              uint64_t *lowaddr, uint64_t *highaddr,
 195                              int elf_machine, int clear_lsb)
 196{
 197    struct elfhdr ehdr;
 198    struct elf_phdr *phdr = NULL, *ph;
 199    int size, i, total_size;
 200    elf_word mem_size;
 201    uint64_t addr, low = (uint64_t)-1, high = 0;
 202    uint8_t *data = NULL;
 203    char label[128];
 204
 205    if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
 206        goto fail;
 207    if (must_swab) {
 208        glue(bswap_ehdr, SZ)(&ehdr);
 209    }
 210
 211    switch (elf_machine) {
 212        case EM_PPC64:
 213            if (EM_PPC64 != ehdr.e_machine)
 214                if (EM_PPC != ehdr.e_machine)
 215                    goto fail;
 216            break;
 217        case EM_X86_64:
 218            if (EM_X86_64 != ehdr.e_machine)
 219                if (EM_386 != ehdr.e_machine)
 220                    goto fail;
 221            break;
 222        case EM_MICROBLAZE:
 223            if (EM_MICROBLAZE != ehdr.e_machine)
 224                if (EM_MICROBLAZE_OLD != ehdr.e_machine)
 225                    goto fail;
 226            break;
 227        default:
 228            if (elf_machine != ehdr.e_machine)
 229                goto fail;
 230    }
 231
 232    if (pentry)
 233        *pentry = (uint64_t)(elf_sword)ehdr.e_entry;
 234
 235    glue(load_symbols, SZ)(&ehdr, fd, must_swab, clear_lsb);
 236
 237    size = ehdr.e_phnum * sizeof(phdr[0]);
 238    lseek(fd, ehdr.e_phoff, SEEK_SET);
 239    phdr = g_malloc0(size);
 240    if (!phdr)
 241        goto fail;
 242    if (read(fd, phdr, size) != size)
 243        goto fail;
 244    if (must_swab) {
 245        for(i = 0; i < ehdr.e_phnum; i++) {
 246            ph = &phdr[i];
 247            glue(bswap_phdr, SZ)(ph);
 248        }
 249    }
 250
 251    total_size = 0;
 252    for(i = 0; i < ehdr.e_phnum; i++) {
 253        ph = &phdr[i];
 254        if (ph->p_type == PT_LOAD) {
 255            mem_size = ph->p_memsz;
 256            /* XXX: avoid allocating */
 257            data = g_malloc0(mem_size);
 258            if (ph->p_filesz > 0) {
 259                if (lseek(fd, ph->p_offset, SEEK_SET) < 0)
 260                    goto fail;
 261                if (read(fd, data, ph->p_filesz) != ph->p_filesz)
 262                    goto fail;
 263            }
 264            /* address_offset is hack for kernel images that are
 265               linked at the wrong physical address.  */
 266            if (translate_fn) {
 267                addr = translate_fn(translate_opaque, ph->p_paddr);
 268            } else {
 269                addr = ph->p_paddr;
 270            }
 271
 272            /* the entry pointer in the ELF header is a virtual
 273             * address, if the text segments paddr and vaddr differ
 274             * we need to adjust the entry */
 275            if (pentry && !translate_fn &&
 276                    ph->p_vaddr != ph->p_paddr &&
 277                    ehdr.e_entry >= ph->p_vaddr &&
 278                    ehdr.e_entry < ph->p_vaddr + ph->p_filesz &&
 279                    ph->p_flags & PF_X) {
 280                *pentry = ehdr.e_entry - ph->p_vaddr + ph->p_paddr;
 281            }
 282
 283            snprintf(label, sizeof(label), "phdr #%d: %s", i, name);
 284            rom_add_blob_fixed(label, data, mem_size, addr);
 285
 286            total_size += mem_size;
 287            if (addr < low)
 288                low = addr;
 289            if ((addr + mem_size) > high)
 290                high = addr + mem_size;
 291
 292            g_free(data);
 293            data = NULL;
 294        }
 295    }
 296    g_free(phdr);
 297    if (lowaddr)
 298        *lowaddr = (uint64_t)(elf_sword)low;
 299    if (highaddr)
 300        *highaddr = (uint64_t)(elf_sword)high;
 301    return total_size;
 302 fail:
 303    g_free(data);
 304    g_free(phdr);
 305    return -1;
 306}
 307