diff options
| -rw-r--r-- | dyngen.c | 160 |
1 files changed, 99 insertions, 61 deletions
@@ -95,6 +95,12 @@ typedef uint64_t host_ulong; #define swabls(x) swab64s(x) #endif +#ifdef ELF_USES_RELOCA +#define SHT_RELOC SHT_RELA +#else +#define SHT_RELOC SHT_REL +#endif + #include "thunk.h" /* all dynamically generated functions begin with this code */ @@ -170,16 +176,24 @@ void elf_swap_phdr(struct elf_phdr *h) swabls(&h->p_align); /* Segment alignment */ } +void elf_swap_rel(ELF_RELOC *rel) +{ + swabls(&rel->r_offset); + swabls(&rel->r_info); +#ifdef ELF_USES_RELOCA + swabls(&rel->r_addend); +#endif +} + /* ELF file info */ int do_swap; struct elf_shdr *shdr; +uint8_t **sdata; struct elfhdr ehdr; ElfW(Sym) *symtab; int nb_syms; char *strtab; -/* data section */ -uint8_t *data_data, *sdata_data; -int data_shndx, sdata_shndx; +int text_shndx; uint16_t get16(uint16_t *p) { @@ -243,6 +257,19 @@ struct elf_shdr *find_elf_section(struct elf_shdr *shdr, int shnum, const char * return NULL; } +int find_reloc(int sh_index) +{ + struct elf_shdr *sec; + int i; + + for(i = 0; i < ehdr.e_shnum; i++) { + sec = &shdr[i]; + if (sec->sh_type == SHT_RELOC && sec->sh_info == sh_index) + return i; + } + return 0; +} + void *load_data(int fd, long offset, unsigned int size) { char *data; @@ -278,7 +305,7 @@ int strstart(const char *str, const char *val, const char **ptr) /* generate op code */ void gen_code(const char *name, host_ulong offset, host_ulong size, - FILE *outfile, uint8_t *text, ELF_RELOC *relocs, int nb_relocs, int reloc_sh_type, + FILE *outfile, uint8_t *text, ELF_RELOC *relocs, int nb_relocs, int gen_switch) { int copy_size = 0; @@ -500,16 +527,39 @@ void gen_code(const char *name, host_ulong offset, host_ulong size, sym_name = strtab + sym->st_name; if (strstart(sym_name, "__op_label", &p)) { uint8_t *ptr; - + int addend; + unsigned long offset; + /* test if the variable refers to a label inside the code we are generating */ - if (sym->st_shndx == data_shndx) - ptr = data_data; - else if (sym->st_shndx == sdata_shndx) - ptr = sdata_data; - else - error("__op_labelN symbols must be in .data or .sdata section"); - val = *(target_ulong *)(ptr + sym->st_value); + ptr = sdata[sym->st_shndx]; + if (!ptr) + error("__op_labelN in invalid section"); + offset = sym->st_value; + addend = 0; +#ifdef ELF_USES_RELOCA + { + int reloc_shndx, nb_relocs1, j; + + /* try to find a matching relocation */ + reloc_shndx = find_reloc(sym->st_shndx); + if (reloc_shndx) { + nb_relocs1 = shdr[reloc_shndx].sh_size / + shdr[reloc_shndx].sh_entsize; + rel = (ELF_RELOC *)sdata[reloc_shndx]; + for(j = 0; j < nb_relocs1; j++) { + if (rel->r_offset == offset) { + addend = rel->r_addend; + break; + } + rel++; + } + } + } +#endif + val = *(target_ulong *)(ptr + offset); + val += addend; + if (val >= start_offset && val < start_offset + copy_size) { n = strtol(p, NULL, 10); fprintf(outfile, " label_offsets[%d] = %d + (gen_code_ptr - gen_code_buf);\n", n, val - start_offset); @@ -886,8 +936,9 @@ int load_elf(const char *filename, FILE *outfile, int do_print_enum) ElfW(Sym) *sym; char *shstr; uint8_t *text; - void *relocs; - int nb_relocs, reloc_sh_type; + ELF_RELOC *relocs; + int nb_relocs; + ELF_RELOC *rel; fd = open(filename, O_RDONLY); if (fd < 0) @@ -926,58 +977,45 @@ int load_elf(const char *filename, FILE *outfile, int do_print_enum) } } + /* read all section data */ + sdata = malloc(sizeof(void *) * ehdr.e_shnum); + memset(sdata, 0, sizeof(void *) * ehdr.e_shnum); + + for(i = 0;i < ehdr.e_shnum; i++) { + sec = &shdr[i]; + if (sec->sh_type != SHT_NOBITS) + sdata[i] = load_data(fd, sec->sh_offset, sec->sh_size); + } + sec = &shdr[ehdr.e_shstrndx]; - shstr = load_data(fd, sec->sh_offset, sec->sh_size); + shstr = sdata[ehdr.e_shstrndx]; + /* swap relocations */ + for(i = 0; i < ehdr.e_shnum; i++) { + sec = &shdr[i]; + if (sec->sh_type == SHT_RELOC) { + nb_relocs = sec->sh_size / sec->sh_entsize; + if (do_swap) { + for(j = 0, rel = (ELF_RELOC *)sdata[i]; j < nb_relocs; j++, rel++) + elf_swap_rel(rel); + } + } + } /* text section */ text_sec = find_elf_section(shdr, ehdr.e_shnum, shstr, ".text"); if (!text_sec) error("could not find .text section"); - text = load_data(fd, text_sec->sh_offset, text_sec->sh_size); + text_shndx = text_sec - shdr; + text = sdata[text_shndx]; - data_shndx = -1; - sec = find_elf_section(shdr, ehdr.e_shnum, shstr, ".data"); - if (sec) { - data_shndx = sec - shdr; - data_data = load_data(fd, sec->sh_offset, sec->sh_size); - } - sdata_shndx = -1; - sec = find_elf_section(shdr, ehdr.e_shnum, shstr, ".sdata"); - if (sec) { - sdata_shndx = sec - shdr; - sdata_data = load_data(fd, sec->sh_offset, sec->sh_size); - } - /* find text relocations, if any */ - nb_relocs = 0; relocs = NULL; - reloc_sh_type = 0; - for(i = 0; i < ehdr.e_shnum; i++) { - sec = &shdr[i]; - if ((sec->sh_type == SHT_REL || sec->sh_type == SHT_RELA) && - sec->sh_info == (text_sec - shdr)) { - reloc_sh_type = sec->sh_type; - relocs = load_data(fd, sec->sh_offset, sec->sh_size); - nb_relocs = sec->sh_size / sec->sh_entsize; - if (do_swap) { - if (sec->sh_type == SHT_REL) { - ElfW(Rel) *rel = relocs; - for(j = 0, rel = relocs; j < nb_relocs; j++, rel++) { - swabls(&rel->r_offset); - swabls(&rel->r_info); - } - } else { - ElfW(Rela) *rel = relocs; - for(j = 0, rel = relocs; j < nb_relocs; j++, rel++) { - swabls(&rel->r_offset); - swabls(&rel->r_info); - swabls(&rel->r_addend); - } - } - } - break; - } + nb_relocs = 0; + i = find_reloc(text_shndx); + if (i != 0) { + relocs = (ELF_RELOC *)sdata[i]; + nb_relocs = shdr[i].sh_size / shdr[i].sh_entsize; } symtab_sec = find_elf_section(shdr, ehdr.e_shnum, shstr, ".symtab"); @@ -985,8 +1023,8 @@ int load_elf(const char *filename, FILE *outfile, int do_print_enum) error("could not find .symtab section"); strtab_sec = &shdr[symtab_sec->sh_link]; - symtab = load_data(fd, symtab_sec->sh_offset, symtab_sec->sh_size); - strtab = load_data(fd, strtab_sec->sh_offset, strtab_sec->sh_size); + symtab = (ElfW(Sym) *)sdata[symtab_sec - shdr]; + strtab = sdata[symtab_sec->sh_link]; nb_syms = symtab_sec->sh_size / sizeof(ElfW(Sym)); if (do_swap) { @@ -1005,7 +1043,7 @@ int load_elf(const char *filename, FILE *outfile, int do_print_enum) name = strtab + sym->st_name; if (strstart(name, OP_PREFIX, &p)) { gen_code(name, sym->st_value, sym->st_size, outfile, - text, relocs, nb_relocs, reloc_sh_type, 2); + text, relocs, nb_relocs, 2); } } } else { @@ -1071,7 +1109,7 @@ fprintf(outfile, if (sym->st_shndx != (text_sec - shdr)) error("invalid section for opcode (0x%x)", sym->st_shndx); gen_code(name, sym->st_value, sym->st_size, outfile, - text, relocs, nb_relocs, reloc_sh_type, 1); + text, relocs, nb_relocs, 1); } } @@ -1126,7 +1164,7 @@ fprintf(outfile, if (sym->st_shndx != (text_sec - shdr)) error("invalid section for opcode (0x%x)", sym->st_shndx); gen_code(name, sym->st_value, sym->st_size, outfile, - text, relocs, nb_relocs, reloc_sh_type, 0); + text, relocs, nb_relocs, 0); } } } |