diff options
| -rw-r--r-- | backend.h | 104 | ||||
| -rw-r--r-- | fetch.h | 22 | ||||
| -rw-r--r-- | ltrace-elf.h | 2 |
3 files changed, 107 insertions, 21 deletions
@@ -180,6 +180,12 @@ size_t umovebytes (struct Process *proc, void *addr, void *buf, size_t count); * XXX the same points as for get_instruction_pointer apply. */ void *sym2addr(struct Process *proc, struct library_symbol *sym); +/* Obtain address of PLT entry corresponding to relocation RELA in + * file LTE. This is NDX-th PLT entry in the file. + * + * XXX should this return arch_addr_t? */ +GElf_Addr arch_plt_sym_val(struct ltelf *lte, size_t ndx, GElf_Rela *rela); + /* Called at some point after we have attached to PROC. This callback * should insert an introspection breakpoint for handling dynamic * linker library loads. */ @@ -194,47 +200,107 @@ struct Event *next_event(void); /* Called when process PROC was removed. */ void process_removed(struct Process *proc); +/* This should extract entry point address and interpreter (dynamic + * linker) bias if possible. Returns 0 if there were no errors, -1 + * otherwise. Sets *ENTRYP and *INTERP_BIASP to non-zero values if + * the corresponding value is known. Unknown values are set to 0. + * + * XXX This is not currently used, but it will be necessary for proper + * support of PIE binaries. */ +int process_get_entry(struct Process *proc, + arch_addr_t *entryp, + arch_addr_t *interp_biasp); + + +/* Optional callbacks + * + * Some callbacks are only available if backend (arch.h) has a certain + * define. If such a define is not present, default implementation + * (most often doing nothing at all) us used instead. This is used + * for gradual extensions of ltrace, so that backends that are not + * fully up to date, or that don't need certain functionality, keep + * working, while other backends take advantage of the optional + * features. */ + +/* The following callbacks have to be implemented in backend if arch.h + * defines ARCH_HAVE_LTELF_DATA. Those are used to init and destroy + * LTE->arch. arch_elf_init returns 0 on success or a negative value + * on failure. */ int arch_elf_init(struct ltelf *lte, struct library *lib); void arch_elf_destroy(struct ltelf *lte); -enum plt_status { - plt_fail, - plt_ok, - plt_default, -}; - -enum plt_status arch_elf_add_plt_entry(struct Process *p, struct ltelf *l, - const char *n, GElf_Rela *r, size_t i, - struct library_symbol **ret); - +/* The following callbacks have to be implemented in backend if arch.h + * defines ARCH_HAVE_BREAKPOINT_DATA. Those are used to init, + * destroy, and clone SBP->arch. arch_breakpoint_init and + * arch_breakpoint_clone return 0 on success or a negative value on + * failure. */ int arch_breakpoint_init(struct Process *proc, struct breakpoint *sbp); void arch_breakpoint_destroy(struct breakpoint *sbp); int arch_breakpoint_clone(struct breakpoint *retp, struct breakpoint *sbp); +/* The following callbacks have to be implemented in backend if arch.h + * defines ARCH_HAVE_LIBRARY_DATA. Those are used to init, destroy + * and clone LIB->arch. */ void arch_library_init(struct library *lib); void arch_library_destroy(struct library *lib); void arch_library_clone(struct library *retp, struct library *lib); +/* The following callbacks have to be implemented in backend if arch.h + * defines ARCH_HAVE_LIBRARY_SYMBOL_DATA. Those are used to init, + * destroy and clone LIBSYM->arch. arch_library_symbol_init and + * arch_library_symbol_clone return 0 on success or a negative value + * on failure. */ int arch_library_symbol_init(struct library_symbol *libsym); void arch_library_symbol_destroy(struct library_symbol *libsym); int arch_library_symbol_clone(struct library_symbol *retp, struct library_symbol *libsym); +/* The following callbacks have to be implemented in backend if arch.h + * defines ARCH_HAVE_PROCESS_DATA. Those are used to init, destroy + * and clone PROC->arch. arch_process_exec is called to update + * PROC->arch in case that PROC underwent an exec. See notes at + * process_init, process_destroy, process_clone and process_exec in + * proc.h. */ int arch_process_init(struct Process *proc); void arch_process_destroy(struct Process *proc); int arch_process_clone(struct Process *retp, struct Process *proc); int arch_process_exec(struct Process *proc); -/* This should extract entry point address and interpreter (dynamic - * linker) bias if possible. Returns 0 if there were no errors, -1 - * otherwise. Sets *ENTRYP and *INTERP_BIASP to non-zero values if - * the corresponding value is known. Unknown values are set to 0. */ -int process_get_entry(struct Process *proc, - arch_addr_t *entryp, - arch_addr_t *interp_biasp); +enum plt_status { + plt_fail, + plt_ok, + plt_default, +}; -/* This is called after the dynamic linker is done with the - * process startup. */ +/* The following callback has to be implemented in backend if arch.h + * defines ARCH_HAVE_ADD_PLT_ENTRY. + * + * This is called for every PLT relocation R in ELF file LTE, that + * ltrace is about to add to a library constructed in process PROC. + * The corresponding PLT entry is for symbol called NAME, and it's + * I-th relocation in the file. + * + * If this function returns plt_default, PLT address is obtained by + * calling arch_plt_sym_val, and symbol is allocated. If plt_ok or + * plt_default are returned, the chain of symbols passed back in RET + * is added to library under construction. */ +enum plt_status arch_elf_add_plt_entry(struct Process *proc, struct ltelf *lte, + const char *name, GElf_Rela *rela, + size_t i, struct library_symbol **ret); + +/* This callback needs to be implemented if arch.h defines + * ARCH_HAVE_DYNLINK_DONE. It is called after the dynamic linker is + * done with the process startup. */ void arch_dynlink_done(struct Process *proc); +/* If arch.h defines ARCH_HAVE_FETCH_ARG, the following callbacks have + * to be implemented: arch_fetch_arg_init, arch_fetch_arg_clone, + * arch_fetch_arg_done, arch_fetch_arg_next and arch_fetch_retval. + * See fetch.h for details. */ + +/* If arch.h defines both ARCH_HAVE_FETCH_ARG and + * ARCH_HAVE_FETCH_PACK, the following callbacks have to be + * implemented: arch_fetch_param_pack_start, + * arch_fetch_param_pack_end. See fetch.h for details. */ + #endif /* BACKEND_H */ @@ -70,4 +70,26 @@ int fetch_param_pack_start(struct fetch_context *context, /* Called after a parameter pack has been fetched. */ void fetch_param_pack_end(struct fetch_context *context); + +/* The following callbacks have to be implemented in backend if arch.h + * defines ARCH_HAVE_FETCH_ARG. These backend callbacks correspond to + * above functions. */ +struct fetch_context *arch_fetch_arg_init(enum tof type, struct Process *proc, + struct arg_type_info *ret_info); +struct fetch_context *arch_fetch_arg_clone(struct Process *proc, + struct fetch_context *context); +int arch_fetch_arg_next(struct fetch_context *ctx, enum tof type, + struct Process *proc, struct arg_type_info *info, + struct value *valuep); +int arch_fetch_retval(struct fetch_context *ctx, enum tof type, + struct Process *proc, struct arg_type_info *info, + struct value *valuep); +void arch_fetch_arg_done(struct fetch_context *context); + +/* The following callbacks have to be implemented in backend if arch.h + * defines ARCH_HAVE_FETCH_ARG and ARCH_HAVE_FETCH_PACK. */ +int arch_fetch_param_pack_start(struct fetch_context *context, + enum param_pack_flavor ppflavor); +void arch_fetch_param_pack_end(struct fetch_context *context); + #endif /* FETCH_H */ diff --git a/ltrace-elf.h b/ltrace-elf.h index 64d1cb8..c560bb8 100644 --- a/ltrace-elf.h +++ b/ltrace-elf.h @@ -56,8 +56,6 @@ int ltelf_read_library(struct library *lib, struct Process *proc, * point address is stored to *ENTRYP. */ struct library *ltelf_read_main_binary(struct Process *proc, const char *path); -GElf_Addr arch_plt_sym_val(struct ltelf *, size_t, GElf_Rela *); - Elf_Data *elf_loaddata(Elf_Scn *scn, GElf_Shdr *shdr); int elf_get_section_covering(struct ltelf *lte, GElf_Addr addr, Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr); |