Syscalls

The PS4 kernel is based on FreeBSD 9. A list of standard FreeBSD 9.1 system calls can be found here.

Compatibility system calls, and some others, have been disabled. The first custom Sony system call comes at number 99. But PS4 specific syscalls come after the last FreeBSD 9.1 system call, posix_fadvise, syscall 531. Currently, the last custom Sony system call is 677 (FW 6.51). Calling any system call higher than 677 gives the same result as calling a compatibility or unimplemented system call: a "There is not enough free system memory" error/segfault.

As of FW 1.76, of the 85 explored sony system calls (532 - 617):

• Two will not be implemented in retail units (possibly in devkits though) and return 0x4E ENOSYS, being sys_dynlib_dlopen and sys_dl_notify_event
• Eight will return 0x4E ENOSYS should the caller be lacking credentials (td->td_proc->p_ucred)
• Four will return 0x4E ENOSYS should the caller have insufficient privileges (uid0)
• Three will return 0x01 EPERM should the caller have insufficient privileges (uid0)
• One explicitly requires a development kit (sys_set_gpo), as it sets output to debug LEDs that only development kit units have.

Reverse engineering

Syscalls are mostly called by libkernel.sprx that exports wrappers to application. For example libkernel exports sceIoOpen function that is a wrapper to sys_open syscall.

https://i.gyazo.com/aa2bceacf5e5f45a15495fcdb79585cb.png

You can find an IDA Pro .idc script made by Cloverleafswag3 to label system calls in libkernel here An updated, janky, hacky version by X41 can be found here

Functions of PS4 custom system calls

Known calls include those relating to:

1. Modules
2. Memory
3. Sandboxing
4. Semaphores

Other potential calls could be for:

1. Mutexes

Other operations, such as file I/O and networking are handled through the standard FreeBSD 9.0 system calls which can be found linked above.

PS4 custom system calls

#syscall ID	FW Ver	Name	Prototype	Notes
99	<=1.01?	sys_netcontrol	int sys_netcontrol(int fd, uint op, void *buf, uint nbuf)	-
101	<=1.01?	sys_netabort	-	-
102	<=1.01?	sys_netgetsockinfo	-	-
113	<=1.01?	sys_socketex	int sys_socketex(const char *name, int domain, int type, int protocol)	Like existing socket syscall, but with the addition of a name argument.
114	<=1.01?	sys_socketclose	-	-
125	<=1.01?	sys_netgetiflist	-	-
141	<=1.01?	sys_kqueueex	-	-
379	>1.01 <=1.76?	sys_mtypeprotect	-	-
532	<=1.76?	sys_regmgr_call	-	-
533	<=1.01?	sys_jitshm_create	-	Only callable from a jit compiler process, else returns EPERM (0x1)
534	<=1.01?	sys_jitshm_alias	-	Only callable from a jit compiler/application process, else returns EPERM (0x1)
535	<=1.01?	sys_dl_get_list	-	Only callable from a debugger, core dump, or syscore process, else returns EPERM (0x1)
536	<=1.01?	sys_dl_get_info	-	Only callable from a debugger, core dump, or syscore process, else returns EPERM (0x1)
537	<=1.01?	sys_dl_notify_event	-	Always returns ENOSYS (0x4E) (may only be implemented in devkits)
538	<=1.01?	sys_evf_create	int sys_evf_create(char* name, int flag, struct evFlag *evf)	-
539	<=1.01?	sys_evf_delete	int sys_evf_delete(int id)	-
540	<=1.01?	sys_evf_open	int sys_evf_open(struct evFlag *evf)	-
541	<=1.01?	sys_evf_close	int sys_evf_close(int id)	-
542	<=1.01?	sys_evf_wait	-	-
543	<=1.01?	sys_evf_trywait	-	-
544	<=1.01?	sys_evf_set	int sys_evf_set(int id)	-
545	<=1.01?	sys_evf_clear	int sys_evf_clear(int id)	-
546	<=1.01?	sys_evf_cancel	int sys_evf_cancel(int id)	-
547	<=1.01?	sys_query_memory_protection	-	-
548	<=1.01?	sys_batch_map	-	-
549	<=1.01?	sys_osem_create	-	-
550	<=1.01?	sys_osem_delete	-	-
551	<=1.01?	sys_osem_open	-	-
552	<=1.01?	sys_osem_close	-	-
553	<=1.01?	sys_osem_wait	-	-
554	<=1.01?	sys_osem_trywait	-	-
555	<=1.01?	sys_osem_post	-	-
556	<=1.01?	sys_osem_cancel	-	-
557	<=1.01?	sys_namedobj_create	-	-
558	<=1.01?	sys_namedobj_delete	-	-
559	<=1.01?	sys_set_vm_container	-	Successful call requires privileges (uid0), else returns EPERM (0x1)
560	<=1.01?	sys_debug_init	-	-
561	<=1.01?	sys_suspend_process	int sys_suspend_process(int pid)	Successful call requires credentials (td->td_proc->p_ucred), else returns EPERM (0x1)
562	<=1.01?	sys_resume_process	int sys_resume_process(int pid)	Successful call requires credentials (td->td_proc->p_ucred), else returns EPERM (0x1)
563	<=1.01?	sys_opmc_enable	-	-
564	<=1.01?	sys_opmc_disable	-	-
565	<=1.01?	sys_opmc_set_ctl	-	-
566	<=1.01?	sys_opmc_set_ctr	-	-
567	<=1.01?	sys_opmc_get_ctr	-	-
568	<=1.01?	sys_budget_create	-	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
569	<=1.01?	sys_budget_delete	-	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
570	<=1.01?	sys_budget_get	-	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
571	<=1.01?	sys_budget_set	-	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
572	<=1.01?	sys_virtual_query	int sys_virtual_query(uint64_t addr, uint64_t unk, void *info, uint64_t info_size)	-
573	<=1.01?	sys_mdbg_call	-	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
574	<=1.01?	sys_sblock_create	-	-
575	<=1.01?	sys_sblock_delete	-	-
576	<=1.01?	sys_sblock_enter	-	-
577	<=1.01?	sys_sblock_exit	-	-
578	<=1.01?	sys_sblock_xenter	-	-
579	<=1.01?	sys_sblock_xexit	-	-
580	<=1.01?	sys_eport_create	-	-
581	<=1.01?	sys_eport_delete	-	-
582	<=1.01?	sys_eport_trigger	-	-
583	<=1.01?	sys_eport_open	-	-
584	<=1.01?	sys_eport_close	-	-
585	<=1.01?	sys_is_in_sandbox	-	-
586	<=1.01?	sys_dmem_container	-	Successful call requires privileges (uid0), else returns EPERM (0x1)
587	<=1.01?	sys_get_authinfo	-	Some functionality requires privileges (uid0)
588	<=1.01?	sys_mname	-	-
589	<=1.01?	sys_dynlib_dlopen	-	Always returns ENOSYS (0x4E) (may only be implemented in devkits)
590	<=1.01?	sys_dynlib_dlclose	-	-
591	<=1.01?	sys_dynlib_dlsym	int sys_dynlib_dlsym(SceKernelModule handle, const char *symbol, void **addrp)	-
592	<=1.01?	sys_dynlib_get_list	int sys_dynlib_get_list(SceKernelModule *pArray, size_t numArray, size_t * pActualNum)	-
593	<=1.01?	sys_dynlib_get_info	int sys_dynlib_get_info(SceKernelModule handle, SceDbgModuleInfo *pInfo)	Sony has stripped module information since 1.76 FW (STO) *
594	<=1.01?	sys_dynlib_load_prx	int sys_dynlib_load_prx(const char *moduleFileName, size_t args, const void *argp, uint32_t flags, const SceKernelLoadModuleOpt *pOpt, int *pRes)	-
595	<=1.01?	sys_dynlib_unload_prx	int sys_dynlib_unload_prx(SceKernelModule handle, size_t args, const void *argp, uint32_t flags, const SceKernelUnloadModuleOpt *pOpt, int *pRes)	-
596	<=1.01?	sys_dynlib_do_copy_relocations	-	-
597	<=1.01?	sys_dynlib_prepare_dlclose	-	Contains an exploitable integer overflow on FWs <= 1.76
598	<=1.01?	sys_dynlib_get_proc_param	-	-
599	<=1.01?	sys_dynlib_process_needed_and_relocate	-	-
600	<=1.01?	sys_sandbox_path	-	Successful call requires credentials (td->td_proc->p_ucred), else returns EPERM (0x1)
601	<=1.01?	sys_mdbg_service	-	-
602	<=1.01?	sys_randomized_path	-	Some functionality requires privileges (uid0)
603	<=1.01?	sys_rdup	-	Successful call requires privileges (uid0), else returns EPERM (0x1)
604	<=1.01?	sys_dl_get_metadata	-	Only callable from a debugger, core dump, or syscore process, else returns EPERM (0x1)
605	<=1.01?	sys_workaround8849	-	-
606	<=1.01?	sys_is_development_mode	-	-
607	<=1.01?	sys_get_self_auth_info	-	-
608	<=1.01?	sys_dynlib_get_info_ex	int sys_dynlib_get_info_ex(int moduleHandle, struct Unk *unk, int *destModuleInfoEx)	-
609	<=1.01?	sys_budget_getid	int sys_budget_getid(void)	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
610	<=1.01?	sys_budget_get_ptype	int sys_budget_get_ptype(int budgetID)	-
611	<=1.01?	sys_get_paging_stats_of_all_threads	-	Successful call requires credentials (td->td_proc->p_ucred), else returns EPERM (0x1)
612	<=1.01?	sys_get_proc_type_info	int sys_get_proc_type_info(int *destProcessInfo)	Only callable from certain processes mainly involving media and JiT
613	>1.01 <=1.76?	sys_get_resident_count	int sys_get_resident_count(int pid)	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
614	<=1.76?	sys_prepare_to_suspend_process	int sys_prepare_to_suspend_process(int pid)	Successful call requires credentials (td->td_proc->p_ucred), else returns ENOSYS (0x4E)
615	<=1.76?	sys_get_resident_fmem_count	int sys_get_resident_fmem_count(int pid)	Some functionality requires privileges (uid0)
616	<=1.76?	sys_thr_get_name	int sys_thr_get_name(int threadID)	-
617	<=1.76?	sys_set_gpo	-	Only callable on development kit (devkit) units
618	>1.76?	sys_get_paging_stats_of_all_objects	-
619	>1.76?	sys_test_debug_rwmem	-
620	>1.76?	sys_free_stack	-
621	>1.76?	sys_suspend_system	-
622	>1.76?	sys_ipmimgr_call	-
623	>1.76?	sys_get_gpo	-
624	>1.76?	sys_get_vm_map_timestamp	-
625	>1.76?	sys_opmc_set_hw	-
626	>1.76?	sys_opmc_get_hw	-
627	>1.76?	sys_get_cpu_usage_all	-
628	>1.76?	sys_mmap_dmem	-
629	>1.76?	sys_physhm_open	-
630	>1.76?	sys_physhm_unlink	-
631	>1.76?	sys_resume_internal_hdd	-
632	>1.76?	sys_thr_suspend_ucontext	-
633	>1.76?	sys_thr_resume_ucontext	-
634	>1.76?	sys_thr_get_ucontext	-
635	>1.76?	sys_thr_set_ucontext	-
636	>1.76?	sys_set_timezone_info	-
637	>1.76?	sys_set_phys_fmem_limit	-
638	>1.76?	sys_utc_to_localtime	-
639	>1.76?	sys_localtime_to_utc	-
640	>1.76?	sys_set_uevt	-
641	>1.76?	sys_get_cpu_usage_proc	-
642	>1.76?	sys_get_map_statistics	-
643	>1.76?	sys_set_chicken_switches	-
644	?>4.05>3.55?	sys_extend_page_table_pool	int sys_extend_page_table_pool(void)
645	?>4.05>3.55??	sys_extend_page_table_pool2	int sys_extend_page_table_pool2(void)	Duplicate of sys_extend_page_table_pool.
646	>1.76?	sys_get_kernel_mem_statistics	-
647	>1.76?	sys_get_sdk_compiled_version	-
648	>1.76?	sys_app_state_change	-
649	>1.76?	sys_dynlib_get_obj_member	-
650	>1.76?	sys_budget_get_ptype_of_budget	-
651	>1.76?	sys_prepare_to_resume_process	-
652	>1.76?	sys_process_terminate	-
653	>1.76?	sys_blockpool_open	-
654	>1.76?	sys_blockpool_map	-
655	>1.76?	sys_blockpool_unmap	-
656	>1.76?	sys_dynlib_get_info_for_libdbg	-
657	>1.76?	sys_blockpool_batch	-
658	>1.76?	sys_fdatasync	-
659	>1.76?	sys_dynlib_get_list2	-
660	>1.76?	sys_dynlib_get_info2	-
661	>1.76?	sys_aio_submit	-
662	>1.76?	sys_aio_multi_delete	-
663	>1.76?	sys_aio_multi_wait	-
664	>1.76?	sys_aio_multi_poll	-
665	>1.76?	sys_aio_get_data	-
666	>1.76?	sys_aio_multi_cancel	-
667	>1.76?	sys_get_bio_usage_all	-
668	>1.76?	sys_aio_create	-
669	>1.76?	sys_aio_submit_cmd	-
670	>1.76?	sys_aio_init	-
671	>1.76?	sys_get_page_table_stats	-
672	>1.76?	sys_dynlib_get_list_for_libdbg	-
673	?> 5.07?	sys_blockpool_move	-
674	?> 5.07?	sys_virtual_query_all	-
675	?> 5.07?	sys_reserve_2mb_page	-
676	?> 5.07?	sys_cpumode_yield	-
677	?>= 6.50? (not present on 6.20)	sys_get_phys_page_size	-	Not present in PS5 PS4EMU on PS5 FW 2.20.

* Since 1.76, Sony has removed key information from sys_dynlib_get_info() (syscall 593), eg. it does not return the module's code base address, data base address, code size, or the data size.

Note: All system calls actually have the thread pointer as the first argument (struct thread *td), however since it's common among all system calls it's been omitted for readability.