/*	$OpenBSD: boot.h,v 1.28 2017/01/29 22:31:09 chl Exp $ */

/*

 * Copyright (c) 1998 Per Fogelstrom, Opsycon AB

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY

 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 */

/*

 * IMPORTANT: any functions below are NOT protected by SSP.  Please

 * do not add anything except what is required to reach GOT with

 * an adjustment.

 */

#define	_DYN_LOADER

#include <sys/types.h>

#include <sys/mman.h>

#include <sys/exec.h>

#include <sys/sysctl.h>

#include <nlist.h>

#include <link.h>

#include <dlfcn.h>

#include "syscall.h"

#include "archdep.h"

#include "path.h"

#include "resolve.h"

#include "sod.h"

#include "stdlib.h"

/*

 * Use the internal, hidden name for any syscalls we need, to avoid

 * accidental override by application code

 */

#define REDIRECT_SYSCALL(x)	typeof(x) x asm("_libc_"#x) __dso_hidden

REDIRECT_SYSCALL(mprotect);

#ifdef RCRT0

#define	DT_PROC(n)	((n) - DT_LOPROC)

#if RELOC_TAG == DT_RELA

typedef	Elf_RelA	RELOC_TYPE;

#elif RELOC_TAG == DT_REL

typedef	Elf_Rel		RELOC_TYPE;

#else

# error "unknown RELOC_TAG"

#endif

/* The set of dynamic tags that we're interested in for bootstrapping */

struct boot_dyn {

	RELOC_TYPE	*dt_reloc;	/* DT_RELA   or DT_REL */

	Elf_Addr	dt_relocsz;	/* DT_RELASZ or DT_RELSZ */

	Elf_Addr	*dt_pltgot;

	Elf_Addr	dt_pltrelsz;

	const Elf_Sym	*dt_symtab;

	RELOC_TYPE	*dt_jmprel;

#if DT_PROCNUM > 0

	u_long		dt_proc[DT_PROCNUM];

#endif

};

/*

 * Local decls.

 */

void _dl_boot_bind(const long, long *, Elf_Dyn *);

void

_dl_boot_bind(const long sp, long *dl_data, Elf_Dyn *dynamicp)

{

	AuxInfo		*auxstack;

	long		*stack;

	Elf_Dyn		*dynp;

	int		n, argc;

	char		**argv, **envp;

	long		loff;

	RELOC_TYPE	*rp;

	Elf_Phdr	*phdp;

	Elf_Addr	i;

	/*

	 * Scan argument and environment vectors. Find dynamic

	 * data vector put after them.

	 */

		;

	/*

	 * Zero out dl_data.

	 */

	/*

	 * Dig out auxiliary data set up by exec call. Move all known

	 * tags to an indexed local table for easy access.

	 */

			continue;

	/*

	 * We need to do 'selfreloc' in case the code weren't

	 * loaded at the address it was linked to.

	 *

	 * Scan the DYNAMIC section for the loader.

	 * Cache the data for easier access.

	 */

	dynp = dynamicp;

		/* first the tags that are pointers to be relocated */

		/* Now for the tags that are just sizes or counts */

#if DT_PROCNUM > 0

		else if (dynp->d_tag >= DT_LOPROC &&

		    dynp->d_tag < DT_LOPROC + DT_PROCNUM)

			dynld.dt_proc[dynp->d_tag - DT_LOPROC] =

			    dynp->d_un.d_val;

#endif /* DT_PROCNUM */

	}

		const Elf_Sym *sp;

#ifdef HAVE_JMPREL

			Elf_Addr *ra = (Elf_Addr *)(rp->r_offset + loff);

			RELOC_JMPREL(rp, sp, ra, loff, dynld.dt_pltgot);

#else

#endif

		}

	}

		Elf_Addr *ra;

		const Elf_Sym *sp;

	}

	RELOC_GOT(&dynld, loff);

	/*

	 * we have been fully relocated here, so most things no longer

	 * need the loff adjustment

	 */

	/*

	 * No further changes to the PLT and/or GOT are needed so make

	 * them read-only.

	 */

	/* do any RWX -> RX fixups for executable PLTs and apply GNU_RELRO */

#if defined(__alpha__) || defined(__hppa__) || defined(__powerpc__) || \

    defined(__sparc64__)

		case PT_LOAD:

			if ((phdp->p_flags & (PF_X | PF_W)) != (PF_X | PF_W))

				break;

			mprotect((void *)(phdp->p_vaddr + loff), phdp->p_memsz,

			    PROT_READ);

			break;

#endif

		case PT_GNU_RELRO:

			    PROT_READ);

			/*

			 * GNU_RELRO (a) covers the GOT, and (b) comes after

			 * all LOAD sections, so if we found it then we're done

			 */

		}

	}

#ifdef __alpha__

void	_reloc_alpha_got(Elf_Dyn *dynp, Elf_Addr relocbase);

void

_reloc_alpha_got(Elf_Dyn *dynp, Elf_Addr relocbase)

{

	const Elf_RelA *rela = 0, *relalim;

	Elf_Addr relasz = 0;

	Elf_Addr *where;

	for (; dynp->d_tag != DT_NULL; dynp++) {

		switch (dynp->d_tag) {

		case DT_RELA:

			rela = (const Elf_RelA *)(relocbase + dynp->d_un.d_ptr);

			break;

		case DT_RELASZ:

			relasz = dynp->d_un.d_val;

			break;

		}

	}

	relalim = (const Elf_RelA *)((caddr_t)rela + relasz);

	for (; rela < relalim; rela++) {

		if (ELF64_R_TYPE(rela->r_info) != RELOC_RELATIVE)

			continue;

		where = (Elf_Addr *)(relocbase + rela->r_offset);

		*where += (Elf_Addr)relocbase;

	}

}

#endif

#endif /* RCRT0 */