diff options
| -rw-r--r-- | bfd/bfd-in.h | 17 | ||||
| -rw-r--r-- | bfd/elf-bfd.h | 13 | ||||
| -rw-r--r-- | bfd/elfcode.h | 226 | ||||
| -rw-r--r-- | bfd/elfxx-target.h | 4 |
4 files changed, 259 insertions, 1 deletions
diff --git a/bfd/bfd-in.h b/bfd/bfd-in.h index 93fd0fd..703f328 100644 --- a/bfd/bfd-in.h +++ b/bfd/bfd-in.h @@ -694,6 +694,22 @@ extern long bfd_get_elf_phdr_upper_bound extern int bfd_get_elf_phdrs PARAMS ((bfd *abfd, void *phdrs)); +/* Create a new BFD as if by bfd_openr. Rather than opening a file, + reconstruct an ELF file by reading the segments out of remote memory + based on the ELF file header at EHDR_VMA and the ELF program headers it + points to. If not null, *LOADBASEP is filled in with the difference + between the VMAs from which the segments were read, and the VMAs the + file headers (and hence BFD's idea of each section's VMA) put them at. + + The function TARGET_READ_MEMORY is called to copy LEN bytes from the + remote memory at target address VMA into the local buffer at MYADDR; it + should return zero on success or an `errno' code on failure. TEMPL must + be a BFD for an ELF target with the word size and byte order found in + the remote memory. */ +extern bfd *bfd_elf_bfd_from_remote_memory + PARAMS ((bfd *templ, bfd_vma ehdr_vma, bfd_vma *loadbasep, + int (*target_read_memory) (bfd_vma vma, char *myaddr, int len))); + /* Return the arch_size field of an elf bfd, or -1 if not elf. */ extern int bfd_get_arch_size PARAMS ((bfd *)); @@ -849,4 +865,3 @@ extern void bfd_ticoff_set_section_load_page extern int bfd_ticoff_get_section_load_page PARAMS ((struct sec *)); - diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index 46f612a..1da6055 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h @@ -875,6 +875,12 @@ struct elf_backend_data Used for the MIPS ELF .mdebug section. */ const struct ecoff_debug_swap *elf_backend_ecoff_debug_swap; + /* This function implements `bfd_elf_bfd_from_remote_memory'; + see elf.c, elfcode.h. */ + bfd *(*elf_backend_bfd_from_remote_memory) + PARAMS ((bfd *templ, bfd_vma ehdr_vma, bfd_vma *loadbasep, + int (*target_read_memory) (bfd_vma vma, char *myaddr, int len))); + /* Alternate EM_xxxx machine codes for this backend. */ int elf_machine_alt1; int elf_machine_alt2; @@ -1750,6 +1756,13 @@ extern char *elfcore_write_prxfpreg extern char *elfcore_write_lwpstatus PARAMS ((bfd *, char *, int *, long, int, const PTR)); +extern bfd *_bfd_elf32_bfd_from_remote_memory + PARAMS ((bfd *templ, bfd_vma ehdr_vma, bfd_vma *loadbasep, + int (*target_read_memory) (bfd_vma, char *, int))); +extern bfd *_bfd_elf64_bfd_from_remote_memory + PARAMS ((bfd *templ, bfd_vma ehdr_vma, bfd_vma *loadbasep, + int (*target_read_memory) (bfd_vma, char *, int))); + /* SH ELF specific routine. */ extern bfd_boolean _sh_elf_set_mach_from_flags diff --git a/bfd/elfcode.h b/bfd/elfcode.h index 0be8048..55c5b42 100644 --- a/bfd/elfcode.h +++ b/bfd/elfcode.h @@ -1568,6 +1568,232 @@ elf_symbol_flags (flags) } #endif +/* Create a new BFD as if by bfd_openr. Rather than opening a file, + reconstruct an ELF file by reading the segments out of remote memory + based on the ELF file header at EHDR_VMA and the ELF program headers it + points to. If not null, *LOADBASEP is filled in with the difference + between the VMAs from which the segments were read, and the VMAs the + file headers (and hence BFD's idea of each section's VMA) put them at. + + The function TARGET_READ_MEMORY is called to copy LEN bytes from the + remote memory at target address VMA into the local buffer at MYADDR; it + should return zero on success or an `errno' code on failure. TEMPL must + be a BFD for a target with the word size and byte order found in the + remote memory. */ + +bfd * +NAME(_bfd_elf,bfd_from_remote_memory) (templ, ehdr_vma, loadbasep, + target_read_memory) + bfd *templ; + bfd_vma ehdr_vma; + bfd_vma *loadbasep; + int (*target_read_memory) PARAMS ((bfd_vma vma, char *myaddr, int len)); +{ + Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ + Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */ + Elf_External_Phdr *x_phdrs; + Elf_Internal_Phdr *i_phdrs, *last_phdr; + bfd *nbfd; + struct bfd_in_memory *bim; + int contents_size; + char *contents; + int err; + unsigned int i; + bfd_vma loadbase; + + /* Read in the ELF header in external format. */ + err = target_read_memory (ehdr_vma, (char *) &x_ehdr, sizeof x_ehdr); + if (err) + { + bfd_set_error (bfd_error_system_call); + errno = err; + return NULL; + } + + /* Now check to see if we have a valid ELF file, and one that BFD can + make use of. The magic number must match, the address size ('class') + and byte-swapping must match our XVEC entry. */ + + if (! elf_file_p (&x_ehdr) + || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT + || x_ehdr.e_ident[EI_CLASS] != ELFCLASS) + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + /* Check that file's byte order matches xvec's */ + switch (x_ehdr.e_ident[EI_DATA]) + { + case ELFDATA2MSB: /* Big-endian */ + if (! bfd_header_big_endian (templ)) + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + break; + case ELFDATA2LSB: /* Little-endian */ + if (! bfd_header_little_endian (templ)) + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + break; + case ELFDATANONE: /* No data encoding specified */ + default: /* Unknown data encoding specified */ + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr); + + /* The file header tells where to find the program headers. + These are what we use to actually choose what to read. */ + + if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0) + { + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + x_phdrs = (Elf_External_Phdr *) + bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs)); + if (x_phdrs == NULL) + { + bfd_set_error (bfd_error_no_memory); + return NULL; + } + err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (char *) x_phdrs, + i_ehdr.e_phnum * sizeof x_phdrs[0]); + if (err) + { + free (x_phdrs); + bfd_set_error (bfd_error_system_call); + errno = err; + return NULL; + } + i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum]; + + contents_size = 0; + last_phdr = NULL; + loadbase = ehdr_vma; + for (i = 0; i < i_ehdr.e_phnum; ++i) + { + elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]); + if (i_phdrs[i].p_type == PT_LOAD) + { + bfd_vma segment_end; + segment_end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz + + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align; + if (segment_end > (bfd_vma) contents_size) + contents_size = segment_end; + + if ((i_phdrs[i].p_offset & -i_phdrs[i].p_align) == 0) + loadbase = ehdr_vma - (i_phdrs[i].p_vaddr & -i_phdrs[i].p_align); + + last_phdr = &i_phdrs[i]; + } + } + if (last_phdr == NULL) + { + /* There were no PT_LOAD segments, so we don't have anything to read. */ + free (x_phdrs); + bfd_set_error (bfd_error_wrong_format); + return NULL; + } + + /* Trim the last segment so we don't bother with zeros in the last page + that are off the end of the file. However, if the extra bit in that + page includes the section headers, keep them. */ + if ((bfd_vma) contents_size > last_phdr->p_offset + last_phdr->p_filesz + && (bfd_vma) contents_size >= (i_ehdr.e_shoff + + i_ehdr.e_shnum * i_ehdr.e_shentsize)) + { + contents_size = last_phdr->p_offset + last_phdr->p_filesz; + if ((bfd_vma) contents_size < (i_ehdr.e_shoff + + i_ehdr.e_shnum * i_ehdr.e_shentsize)) + contents_size = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize; + } + else + contents_size = last_phdr->p_offset + last_phdr->p_filesz; + + /* Now we know the size of the whole image we want read in. */ + contents = (char *) bfd_zmalloc ((bfd_size_type) contents_size); + if (contents == NULL) + { + free (x_phdrs); + bfd_set_error (bfd_error_no_memory); + return NULL; + } + + for (i = 0; i < i_ehdr.e_phnum; ++i) + if (i_phdrs[i].p_type == PT_LOAD) + { + bfd_vma start = i_phdrs[i].p_offset & -i_phdrs[i].p_align; + bfd_vma end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz + + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align; + if (end > (bfd_vma) contents_size) + end = contents_size; + err = target_read_memory ((loadbase + i_phdrs[i].p_vaddr) + & -i_phdrs[i].p_align, + contents + start, end - start); + if (err) + { + free (x_phdrs); + free (contents); + bfd_set_error (bfd_error_system_call); + errno = err; + return NULL; + } + } + free (x_phdrs); + + /* If the segments visible in memory didn't include the section headers, + then clear them from the file header. */ + if ((bfd_vma) contents_size < (i_ehdr.e_shoff + + i_ehdr.e_shnum * i_ehdr.e_shentsize)) + { + memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff); + memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum); + memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx); + } + + /* This will normally have been in the first PT_LOAD segment. But it + conceivably could be missing, and we might have just changed it. */ + memcpy (contents, &x_ehdr, sizeof x_ehdr); + + /* Now we have a memory image of the ELF file contents. Make a BFD. */ + bim = ((struct bfd_in_memory *) + bfd_malloc ((bfd_size_type) sizeof (struct bfd_in_memory))); + if (bim == NULL) + { + free (contents); + bfd_set_error (bfd_error_no_memory); + return NULL; + } + nbfd = _bfd_new_bfd (); + if (nbfd == NULL) + { + free (bim); + free (contents); + bfd_set_error (bfd_error_no_memory); + return NULL; + } + nbfd->filename = "<in-memory>"; + nbfd->xvec = templ->xvec; + bim->size = contents_size; + bim->buffer = contents; + nbfd->iostream = (PTR) bim; + nbfd->flags = BFD_IN_MEMORY; + nbfd->direction = read_direction; + nbfd->mtime = time (NULL); + nbfd->mtime_set = TRUE; + + if (loadbasep) + *loadbasep = loadbase; + return nbfd; +} + #include "elfcore.h" #include "elflink.h" diff --git a/bfd/elfxx-target.h b/bfd/elfxx-target.h index 734d78b..58a96b1 100644 --- a/bfd/elfxx-target.h +++ b/bfd/elfxx-target.h @@ -338,6 +338,9 @@ #ifndef elf_backend_ecoff_debug_swap #define elf_backend_ecoff_debug_swap 0 #endif +#ifndef elf_backend_bfd_from_remote_memory +#define elf_backend_bfd_from_remote_memory _bfd_elfNN_bfd_from_remote_memory +#endif #ifndef elf_backend_got_header_size #define elf_backend_got_header_size 0 #endif @@ -490,6 +493,7 @@ static const struct elf_backend_data elfNN_bed = elf_backend_mips_irix_compat, elf_backend_mips_rtype_to_howto, elf_backend_ecoff_debug_swap, + elf_backend_bfd_from_remote_memory, ELF_MACHINE_ALT1, ELF_MACHINE_ALT2, &elf_backend_size_info, |