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-rw-r--r--include/hw/elf_ops.h611
1 files changed, 611 insertions, 0 deletions
diff --git a/include/hw/elf_ops.h b/include/hw/elf_ops.h
new file mode 100644
index 000000000..995de8495
--- /dev/null
+++ b/include/hw/elf_ops.h
@@ -0,0 +1,611 @@
+static void glue(bswap_ehdr, SZ)(struct elfhdr *ehdr)
+{
+ bswap16s(&ehdr->e_type); /* Object file type */
+ bswap16s(&ehdr->e_machine); /* Architecture */
+ bswap32s(&ehdr->e_version); /* Object file version */
+ bswapSZs(&ehdr->e_entry); /* Entry point virtual address */
+ bswapSZs(&ehdr->e_phoff); /* Program header table file offset */
+ bswapSZs(&ehdr->e_shoff); /* Section header table file offset */
+ bswap32s(&ehdr->e_flags); /* Processor-specific flags */
+ bswap16s(&ehdr->e_ehsize); /* ELF header size in bytes */
+ bswap16s(&ehdr->e_phentsize); /* Program header table entry size */
+ bswap16s(&ehdr->e_phnum); /* Program header table entry count */
+ bswap16s(&ehdr->e_shentsize); /* Section header table entry size */
+ bswap16s(&ehdr->e_shnum); /* Section header table entry count */
+ bswap16s(&ehdr->e_shstrndx); /* Section header string table index */
+}
+
+static void glue(bswap_phdr, SZ)(struct elf_phdr *phdr)
+{
+ bswap32s(&phdr->p_type); /* Segment type */
+ bswapSZs(&phdr->p_offset); /* Segment file offset */
+ bswapSZs(&phdr->p_vaddr); /* Segment virtual address */
+ bswapSZs(&phdr->p_paddr); /* Segment physical address */
+ bswapSZs(&phdr->p_filesz); /* Segment size in file */
+ bswapSZs(&phdr->p_memsz); /* Segment size in memory */
+ bswap32s(&phdr->p_flags); /* Segment flags */
+ bswapSZs(&phdr->p_align); /* Segment alignment */
+}
+
+static void glue(bswap_shdr, SZ)(struct elf_shdr *shdr)
+{
+ bswap32s(&shdr->sh_name);
+ bswap32s(&shdr->sh_type);
+ bswapSZs(&shdr->sh_flags);
+ bswapSZs(&shdr->sh_addr);
+ bswapSZs(&shdr->sh_offset);
+ bswapSZs(&shdr->sh_size);
+ bswap32s(&shdr->sh_link);
+ bswap32s(&shdr->sh_info);
+ bswapSZs(&shdr->sh_addralign);
+ bswapSZs(&shdr->sh_entsize);
+}
+
+static void glue(bswap_sym, SZ)(struct elf_sym *sym)
+{
+ bswap32s(&sym->st_name);
+ bswapSZs(&sym->st_value);
+ bswapSZs(&sym->st_size);
+ bswap16s(&sym->st_shndx);
+}
+
+static void glue(bswap_rela, SZ)(struct elf_rela *rela)
+{
+ bswapSZs(&rela->r_offset);
+ bswapSZs(&rela->r_info);
+ bswapSZs((elf_word *)&rela->r_addend);
+}
+
+static struct elf_shdr *glue(find_section, SZ)(struct elf_shdr *shdr_table,
+ int n, int type)
+{
+ int i;
+ for(i=0;i<n;i++) {
+ if (shdr_table[i].sh_type == type)
+ return shdr_table + i;
+ }
+ return NULL;
+}
+
+static int glue(symfind, SZ)(const void *s0, const void *s1)
+{
+ hwaddr addr = *(hwaddr *)s0;
+ struct elf_sym *sym = (struct elf_sym *)s1;
+ int result = 0;
+ if (addr < sym->st_value) {
+ result = -1;
+ } else if (addr >= sym->st_value + sym->st_size) {
+ result = 1;
+ }
+ return result;
+}
+
+static const char *glue(lookup_symbol, SZ)(struct syminfo *s,
+ hwaddr orig_addr)
+{
+ struct elf_sym *syms = glue(s->disas_symtab.elf, SZ);
+ struct elf_sym *sym;
+
+ sym = bsearch(&orig_addr, syms, s->disas_num_syms, sizeof(*syms),
+ glue(symfind, SZ));
+ if (sym != NULL) {
+ return s->disas_strtab + sym->st_name;
+ }
+
+ return "";
+}
+
+static int glue(symcmp, SZ)(const void *s0, const void *s1)
+{
+ struct elf_sym *sym0 = (struct elf_sym *)s0;
+ struct elf_sym *sym1 = (struct elf_sym *)s1;
+ return (sym0->st_value < sym1->st_value)
+ ? -1
+ : ((sym0->st_value > sym1->st_value) ? 1 : 0);
+}
+
+static void glue(load_symbols, SZ)(struct elfhdr *ehdr, int fd, int must_swab,
+ int clear_lsb, symbol_fn_t sym_cb)
+{
+ struct elf_shdr *symtab, *strtab;
+ g_autofree struct elf_shdr *shdr_table = NULL;
+ g_autofree struct elf_sym *syms = NULL;
+ g_autofree char *str = NULL;
+ struct syminfo *s;
+ int nsyms, i;
+
+ shdr_table = load_at(fd, ehdr->e_shoff,
+ sizeof(struct elf_shdr) * ehdr->e_shnum);
+ if (!shdr_table) {
+ return ;
+ }
+
+ if (must_swab) {
+ for (i = 0; i < ehdr->e_shnum; i++) {
+ glue(bswap_shdr, SZ)(shdr_table + i);
+ }
+ }
+
+ symtab = glue(find_section, SZ)(shdr_table, ehdr->e_shnum, SHT_SYMTAB);
+ if (!symtab) {
+ return;
+ }
+ syms = load_at(fd, symtab->sh_offset, symtab->sh_size);
+ if (!syms) {
+ return;
+ }
+
+ nsyms = symtab->sh_size / sizeof(struct elf_sym);
+
+ /* String table */
+ if (symtab->sh_link >= ehdr->e_shnum) {
+ return;
+ }
+ strtab = &shdr_table[symtab->sh_link];
+
+ str = load_at(fd, strtab->sh_offset, strtab->sh_size);
+ if (!str) {
+ return;
+ }
+
+ i = 0;
+ while (i < nsyms) {
+ if (must_swab) {
+ glue(bswap_sym, SZ)(&syms[i]);
+ }
+ if (sym_cb) {
+ sym_cb(str + syms[i].st_name, syms[i].st_info,
+ syms[i].st_value, syms[i].st_size);
+ }
+ /* We are only interested in function symbols.
+ Throw everything else away. */
+ if (syms[i].st_shndx == SHN_UNDEF ||
+ syms[i].st_shndx >= SHN_LORESERVE ||
+ ELF_ST_TYPE(syms[i].st_info) != STT_FUNC) {
+ nsyms--;
+ if (i < nsyms) {
+ syms[i] = syms[nsyms];
+ }
+ continue;
+ }
+ if (clear_lsb) {
+ /* The bottom address bit marks a Thumb or MIPS16 symbol. */
+ syms[i].st_value &= ~(glue(glue(Elf, SZ), _Addr))1;
+ }
+ i++;
+ }
+
+ /* check we have symbols left */
+ if (nsyms == 0) {
+ return;
+ }
+
+ syms = g_realloc(syms, nsyms * sizeof(*syms));
+ qsort(syms, nsyms, sizeof(*syms), glue(symcmp, SZ));
+ for (i = 0; i < nsyms - 1; i++) {
+ if (syms[i].st_size == 0) {
+ syms[i].st_size = syms[i + 1].st_value - syms[i].st_value;
+ }
+ }
+
+ /* Commit */
+ s = g_malloc0(sizeof(*s));
+ s->lookup_symbol = glue(lookup_symbol, SZ);
+ glue(s->disas_symtab.elf, SZ) = g_steal_pointer(&syms);
+ s->disas_num_syms = nsyms;
+ s->disas_strtab = g_steal_pointer(&str);
+ s->next = syminfos;
+ syminfos = s;
+}
+
+static int glue(elf_reloc, SZ)(struct elfhdr *ehdr, int fd, int must_swab,
+ uint64_t (*translate_fn)(void *, uint64_t),
+ void *translate_opaque, uint8_t *data,
+ struct elf_phdr *ph, int elf_machine)
+{
+ struct elf_shdr *reltab, *shdr_table = NULL;
+ struct elf_rela *rels = NULL;
+ int nrels, i, ret = -1;
+ elf_word wordval;
+ void *addr;
+
+ shdr_table = load_at(fd, ehdr->e_shoff,
+ sizeof(struct elf_shdr) * ehdr->e_shnum);
+ if (!shdr_table) {
+ return -1;
+ }
+ if (must_swab) {
+ for (i = 0; i < ehdr->e_shnum; i++) {
+ glue(bswap_shdr, SZ)(&shdr_table[i]);
+ }
+ }
+
+ reltab = glue(find_section, SZ)(shdr_table, ehdr->e_shnum, SHT_RELA);
+ if (!reltab) {
+ goto fail;
+ }
+ rels = load_at(fd, reltab->sh_offset, reltab->sh_size);
+ if (!rels) {
+ goto fail;
+ }
+ nrels = reltab->sh_size / sizeof(struct elf_rela);
+
+ for (i = 0; i < nrels; i++) {
+ if (must_swab) {
+ glue(bswap_rela, SZ)(&rels[i]);
+ }
+ if (rels[i].r_offset < ph->p_vaddr ||
+ rels[i].r_offset >= ph->p_vaddr + ph->p_filesz) {
+ continue;
+ }
+ addr = &data[rels[i].r_offset - ph->p_vaddr];
+ switch (elf_machine) {
+ case EM_S390:
+ switch (rels[i].r_info) {
+ case R_390_RELATIVE:
+ wordval = *(elf_word *)addr;
+ if (must_swab) {
+ bswapSZs(&wordval);
+ }
+ wordval = translate_fn(translate_opaque, wordval);
+ if (must_swab) {
+ bswapSZs(&wordval);
+ }
+ *(elf_word *)addr = wordval;
+ break;
+ default:
+ fprintf(stderr, "Unsupported relocation type %i!\n",
+ (int)rels[i].r_info);
+ }
+ }
+ }
+
+ ret = 0;
+fail:
+ g_free(rels);
+ g_free(shdr_table);
+ return ret;
+}
+
+/*
+ * Given 'nhdr', a pointer to a range of ELF Notes, search through them
+ * for a note matching type 'elf_note_type' and return a pointer to
+ * the matching ELF note.
+ */
+static struct elf_note *glue(get_elf_note_type, SZ)(struct elf_note *nhdr,
+ elf_word note_size,
+ elf_word phdr_align,
+ elf_word elf_note_type)
+{
+ elf_word nhdr_size = sizeof(struct elf_note);
+ elf_word elf_note_entry_offset = 0;
+ elf_word note_type;
+ elf_word nhdr_namesz;
+ elf_word nhdr_descsz;
+
+ if (nhdr == NULL) {
+ return NULL;
+ }
+
+ note_type = nhdr->n_type;
+ while (note_type != elf_note_type) {
+ nhdr_namesz = nhdr->n_namesz;
+ nhdr_descsz = nhdr->n_descsz;
+
+ elf_note_entry_offset = nhdr_size +
+ QEMU_ALIGN_UP(nhdr_namesz, phdr_align) +
+ QEMU_ALIGN_UP(nhdr_descsz, phdr_align);
+
+ /*
+ * If the offset calculated in this iteration exceeds the
+ * supplied size, we are done and no matching note was found.
+ */
+ if (elf_note_entry_offset > note_size) {
+ return NULL;
+ }
+
+ /* skip to the next ELF Note entry */
+ nhdr = (void *)nhdr + elf_note_entry_offset;
+ note_type = nhdr->n_type;
+ }
+
+ return nhdr;
+}
+
+static ssize_t glue(load_elf, SZ)(const char *name, int fd,
+ uint64_t (*elf_note_fn)(void *, void *, bool),
+ uint64_t (*translate_fn)(void *, uint64_t),
+ void *translate_opaque,
+ int must_swab, uint64_t *pentry,
+ uint64_t *lowaddr, uint64_t *highaddr,
+ uint32_t *pflags, int elf_machine,
+ int clear_lsb, int data_swab,
+ AddressSpace *as, bool load_rom,
+ symbol_fn_t sym_cb)
+{
+ struct elfhdr ehdr;
+ struct elf_phdr *phdr = NULL, *ph;
+ int size, i;
+ ssize_t total_size;
+ elf_word mem_size, file_size, data_offset;
+ uint64_t addr, low = (uint64_t)-1, high = 0;
+ GMappedFile *mapped_file = NULL;
+ uint8_t *data = NULL;
+ ssize_t ret = ELF_LOAD_FAILED;
+
+ if (read(fd, &ehdr, sizeof(ehdr)) != sizeof(ehdr))
+ goto fail;
+ if (must_swab) {
+ glue(bswap_ehdr, SZ)(&ehdr);
+ }
+
+ if (elf_machine <= EM_NONE) {
+ /* The caller didn't specify an ARCH, we can figure it out */
+ elf_machine = ehdr.e_machine;
+ }
+
+ switch (elf_machine) {
+ case EM_PPC64:
+ if (ehdr.e_machine != EM_PPC64) {
+ if (ehdr.e_machine != EM_PPC) {
+ ret = ELF_LOAD_WRONG_ARCH;
+ goto fail;
+ }
+ }
+ break;
+ case EM_X86_64:
+ if (ehdr.e_machine != EM_X86_64) {
+ if (ehdr.e_machine != EM_386) {
+ ret = ELF_LOAD_WRONG_ARCH;
+ goto fail;
+ }
+ }
+ break;
+ case EM_MICROBLAZE:
+ if (ehdr.e_machine != EM_MICROBLAZE) {
+ if (ehdr.e_machine != EM_MICROBLAZE_OLD) {
+ ret = ELF_LOAD_WRONG_ARCH;
+ goto fail;
+ }
+ }
+ break;
+ case EM_MIPS:
+ case EM_NANOMIPS:
+ if ((ehdr.e_machine != EM_MIPS) &&
+ (ehdr.e_machine != EM_NANOMIPS)) {
+ ret = ELF_LOAD_WRONG_ARCH;
+ goto fail;
+ }
+ break;
+ default:
+ if (elf_machine != ehdr.e_machine) {
+ ret = ELF_LOAD_WRONG_ARCH;
+ goto fail;
+ }
+ }
+
+ if (pflags) {
+ *pflags = (elf_word)ehdr.e_flags;
+ }
+ if (pentry)
+ *pentry = (uint64_t)(elf_sword)ehdr.e_entry;
+
+ glue(load_symbols, SZ)(&ehdr, fd, must_swab, clear_lsb, sym_cb);
+
+ size = ehdr.e_phnum * sizeof(phdr[0]);
+ if (lseek(fd, ehdr.e_phoff, SEEK_SET) != ehdr.e_phoff) {
+ goto fail;
+ }
+ phdr = g_malloc0(size);
+ if (!phdr)
+ goto fail;
+ if (read(fd, phdr, size) != size)
+ goto fail;
+ if (must_swab) {
+ for(i = 0; i < ehdr.e_phnum; i++) {
+ ph = &phdr[i];
+ glue(bswap_phdr, SZ)(ph);
+ }
+ }
+
+ /*
+ * Since we want to be able to modify the mapped buffer, we set the
+ * 'writable' parameter to 'true'. Modifications to the buffer are not
+ * written back to the file.
+ */
+ mapped_file = g_mapped_file_new_from_fd(fd, true, NULL);
+ if (!mapped_file) {
+ goto fail;
+ }
+
+ total_size = 0;
+ for(i = 0; i < ehdr.e_phnum; i++) {
+ ph = &phdr[i];
+ if (ph->p_type == PT_LOAD) {
+ mem_size = ph->p_memsz; /* Size of the ROM */
+ file_size = ph->p_filesz; /* Size of the allocated data */
+ data_offset = ph->p_offset; /* Offset where the data is located */
+
+ if (file_size > 0) {
+ if (g_mapped_file_get_length(mapped_file) <
+ file_size + data_offset) {
+ goto fail;
+ }
+
+ data = (uint8_t *)g_mapped_file_get_contents(mapped_file);
+ data += data_offset;
+ }
+
+ /* The ELF spec is somewhat vague about the purpose of the
+ * physical address field. One common use in the embedded world
+ * is that physical address field specifies the load address
+ * and the virtual address field specifies the execution address.
+ * Segments are packed into ROM or flash, and the relocation
+ * and zero-initialization of data is done at runtime. This
+ * means that the memsz header represents the runtime size of the
+ * segment, but the filesz represents the loadtime size. If
+ * we try to honour the memsz value for an ELF file like this
+ * we will end up with overlapping segments (which the
+ * loader.c code will later reject).
+ * We support ELF files using this scheme by by checking whether
+ * paddr + memsz for this segment would overlap with any other
+ * segment. If so, then we assume it's using this scheme and
+ * truncate the loaded segment to the filesz size.
+ * If the segment considered as being memsz size doesn't overlap
+ * then we use memsz for the segment length, to handle ELF files
+ * which assume that the loader will do the zero-initialization.
+ */
+ if (mem_size > file_size) {
+ /* If this segment's zero-init portion overlaps another
+ * segment's data or zero-init portion, then truncate this one.
+ * Invalid ELF files where the segments overlap even when
+ * only file_size bytes are loaded will be rejected by
+ * the ROM overlap check in loader.c, so we don't try to
+ * explicitly detect those here.
+ */
+ int j;
+ elf_word zero_start = ph->p_paddr + file_size;
+ elf_word zero_end = ph->p_paddr + mem_size;
+
+ for (j = 0; j < ehdr.e_phnum; j++) {
+ struct elf_phdr *jph = &phdr[j];
+
+ if (i != j && jph->p_type == PT_LOAD) {
+ elf_word other_start = jph->p_paddr;
+ elf_word other_end = jph->p_paddr + jph->p_memsz;
+
+ if (!(other_start >= zero_end ||
+ zero_start >= other_end)) {
+ mem_size = file_size;
+ break;
+ }
+ }
+ }
+ }
+
+ if (mem_size > SSIZE_MAX - total_size) {
+ ret = ELF_LOAD_TOO_BIG;
+ goto fail;
+ }
+
+ /* address_offset is hack for kernel images that are
+ linked at the wrong physical address. */
+ if (translate_fn) {
+ addr = translate_fn(translate_opaque, ph->p_paddr);
+ glue(elf_reloc, SZ)(&ehdr, fd, must_swab, translate_fn,
+ translate_opaque, data, ph, elf_machine);
+ } else {
+ addr = ph->p_paddr;
+ }
+
+ if (data_swab) {
+ int j;
+ for (j = 0; j < file_size; j += (1 << data_swab)) {
+ uint8_t *dp = data + j;
+ switch (data_swab) {
+ case (1):
+ *(uint16_t *)dp = bswap16(*(uint16_t *)dp);
+ break;
+ case (2):
+ *(uint32_t *)dp = bswap32(*(uint32_t *)dp);
+ break;
+ case (3):
+ *(uint64_t *)dp = bswap64(*(uint64_t *)dp);
+ break;
+ default:
+ g_assert_not_reached();
+ }
+ }
+ }
+
+ /* the entry pointer in the ELF header is a virtual
+ * address, if the text segments paddr and vaddr differ
+ * we need to adjust the entry */
+ if (pentry && !translate_fn &&
+ ph->p_vaddr != ph->p_paddr &&
+ ehdr.e_entry >= ph->p_vaddr &&
+ ehdr.e_entry < ph->p_vaddr + ph->p_filesz &&
+ ph->p_flags & PF_X) {
+ *pentry = ehdr.e_entry - ph->p_vaddr + ph->p_paddr;
+ }
+
+ /* Some ELF files really do have segments of zero size;
+ * just ignore them rather than trying to create empty
+ * ROM blobs, because the zero-length blob can falsely
+ * trigger the overlapping-ROM-blobs check.
+ */
+ if (mem_size != 0) {
+ if (load_rom) {
+ g_autofree char *label =
+ g_strdup_printf("%s ELF program header segment %d",
+ name, i);
+
+ /*
+ * rom_add_elf_program() takes its own reference to
+ * 'mapped_file'.
+ */
+ rom_add_elf_program(label, mapped_file, data, file_size,
+ mem_size, addr, as);
+ } else {
+ MemTxResult res;
+
+ res = address_space_write(as ? as : &address_space_memory,
+ addr, MEMTXATTRS_UNSPECIFIED,
+ data, file_size);
+ if (res != MEMTX_OK) {
+ goto fail;
+ }
+ }
+ }
+
+ total_size += mem_size;
+ if (addr < low)
+ low = addr;
+ if ((addr + mem_size) > high)
+ high = addr + mem_size;
+
+ data = NULL;
+
+ } else if (ph->p_type == PT_NOTE && elf_note_fn) {
+ struct elf_note *nhdr = NULL;
+
+ file_size = ph->p_filesz; /* Size of the range of ELF notes */
+ data_offset = ph->p_offset; /* Offset where the notes are located */
+
+ if (file_size > 0) {
+ if (g_mapped_file_get_length(mapped_file) <
+ file_size + data_offset) {
+ goto fail;
+ }
+
+ data = (uint8_t *)g_mapped_file_get_contents(mapped_file);
+ data += data_offset;
+ }
+
+ /*
+ * Search the ELF notes to find one with a type matching the
+ * value passed in via 'translate_opaque'
+ */
+ nhdr = (struct elf_note *)data;
+ assert(translate_opaque != NULL);
+ nhdr = glue(get_elf_note_type, SZ)(nhdr, file_size, ph->p_align,
+ *(uint64_t *)translate_opaque);
+ if (nhdr != NULL) {
+ elf_note_fn((void *)nhdr, (void *)&ph->p_align, SZ == 64);
+ }
+ data = NULL;
+ }
+ }
+
+ if (lowaddr)
+ *lowaddr = (uint64_t)(elf_sword)low;
+ if (highaddr)
+ *highaddr = (uint64_t)(elf_sword)high;
+ ret = total_size;
+ fail:
+ if (mapped_file) {
+ g_mapped_file_unref(mapped_file);
+ }
+ g_free(phdr);
+ return ret;
+}