diff options
Diffstat (limited to 'libelf/elf_compress.c')
| -rw-r--r-- | libelf/elf_compress.c | 93 |
1 files changed, 57 insertions, 36 deletions
diff --git a/libelf/elf_compress.c b/libelf/elf_compress.c index 6a26c7cb..4be92008 100644 --- a/libelf/elf_compress.c +++ b/libelf/elf_compress.c @@ -217,6 +217,47 @@ __libelf_decompress (void *buf_in, size_t size_in, size_t size_out) return buf_out; } +void * +internal_function +__libelf_decompress_elf (Elf_Scn *scn, size_t *size_out, size_t *addralign) +{ + GElf_Chdr chdr; + if (gelf_getchdr (scn, &chdr) == NULL) + return NULL; + + if (chdr.ch_type != ELFCOMPRESS_ZLIB) + { + __libelf_seterrno (ELF_E_UNKNOWN_COMPRESSION_TYPE); + return NULL; + } + + if (! powerof2 (chdr.ch_addralign)) + { + __libelf_seterrno (ELF_E_INVALID_ALIGN); + return NULL; + } + + /* Take the in-memory representation, so we can even handle a + section that has just been constructed (maybe it was copied + over from some other ELF file first with elf_newdata). This + is slightly inefficient when the raw data needs to be + converted since then we'll be converting the whole buffer and + not just Chdr. */ + Elf_Data *data = elf_getdata (scn, NULL); + if (data == NULL) + return NULL; + + int elfclass = scn->elf->class; + size_t hsize = (elfclass == ELFCLASS32 + ? sizeof (Elf32_Chdr) : sizeof (Elf64_Chdr)); + size_t size_in = data->d_size - hsize; + void *buf_in = data->d_buf + hsize; + void *buf_out = __libelf_decompress (buf_in, size_in, chdr.ch_size); + *size_out = chdr.ch_size; + *addralign = chdr.ch_addralign; + return buf_out; +} + void internal_function __libelf_reset_rawdata (Elf_Scn *scn, void *buf, size_t size, size_t align, @@ -337,53 +378,33 @@ elf_compress (Elf_Scn *scn, int type) return -1; } - GElf_Chdr chdr; - if (gelf_getchdr (scn, &chdr) == NULL) - return -1; - - if (chdr.ch_type != ELFCOMPRESS_ZLIB) + /* If the data is already decompressed (by elf_strptr), then we + only need to setup the rawdata and section header. XXX what + about elf_newdata? */ + if (scn->zdata_base == NULL) { - __libelf_seterrno (ELF_E_UNKNOWN_COMPRESSION_TYPE); - return -1; + size_t size_out, addralign; + void *buf_out = __libelf_decompress_elf (scn, &size_out, &addralign); + if (buf_out == NULL) + return -1; + + scn->zdata_base = buf_out; + scn->zdata_size = size_out; + scn->zdata_align = addralign; } - if (! powerof2 (chdr.ch_addralign)) - { - __libelf_seterrno (ELF_E_INVALID_ALIGN); - return -1; - } - - /* Take the in-memory representation, so we can even handle a - section that has just been constructed (maybe it was copied - over from some other ELF file first with elf_newdata). This - is slightly inefficient when the raw data needs to be - converted since then we'll be converting the whole buffer and - not just Chdr. */ - Elf_Data *data = elf_getdata (scn, NULL); - if (data == NULL) - return -1; - - size_t hsize = (elfclass == ELFCLASS32 - ? sizeof (Elf32_Chdr) : sizeof (Elf64_Chdr)); - size_t size_in = data->d_size - hsize; - void *buf_in = data->d_buf + hsize; - void *buf_out = __libelf_decompress (buf_in, size_in, chdr.ch_size); - if (buf_out == NULL) - return -1; - /* Note we keep the sh_entsize as is, we assume it is setup correctly and ignored when SHF_COMPRESSED is set. */ - shdr.sh_size = chdr.ch_size; - shdr.sh_addralign = chdr.ch_addralign; + shdr.sh_size = scn->zdata_size; + shdr.sh_addralign = scn->zdata_align; shdr.sh_flags &= ~SHF_COMPRESSED; // XXX Don't! this sets dirty flag... gelf_update_shdr (scn, &shdr); - __libelf_reset_rawdata (scn, buf_out, chdr.ch_size, chdr.ch_addralign, + __libelf_reset_rawdata (scn, scn->zdata_base, + scn->zdata_size, scn->zdata_align, __libelf_data_type (elf, shdr.sh_type)); - scn->zdata_base = buf_out; - return 0; } else |