usr/src/lib/libtnfctl/traverse.c - illumos-gate - Gitiles

 /*
  * CDDL HEADER START
  *
  * The contents of this file are subject to the terms of the
  * Common Development and Distribution License, Version 1.0 only
  * (the "License").  You may not use this file except in compliance
  * with the License.
  *
  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  * or http://www.opensolaris.org/os/licensing.
  * See the License for the specific language governing permissions
  * and limitations under the License.
  *
  * When distributing Covered Code, include this CDDL HEADER in each
  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  * If applicable, add the following below this CDDL HEADER, with the
  * fields enclosed by brackets "[]" replaced with your own identifying
  * information: Portions Copyright [yyyy] [name of copyright owner]
  *
  * CDDL HEADER END
  */
 /*
  * Copyright (c) 1994, by Sun Microsytems, Inc.
  */

 #pragma ident	"%Z%%M%	%I%	%E% SMI"

 /*
  * Generic functions that know how to traverse elf sections in an object.
  * Also functions that know how to traverse records in a section.
  *
  */

 #include <string.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <errno.h>
 #include <sys/procfs.h>
 #include <sys/stat.h>

 #include "tnfctl_int.h"
 #include "dbg.h"


 /*
  * _tnfctl_traverse_object() - traverses all of the elf sections in an object,
  * calling the supplied function on each.
  */
 tnfctl_errcode_t
 _tnfctl_traverse_object(int objfd, uintptr_t addr,
 			tnfctl_elf_search_t *search_info_p)
 {
 	Elf		*elf;
 	GElf_Ehdr	*ehdr, ehdr_obj;
 	char		*strs;
 	GElf_Shdr	*shdr, shdr_obj;
 	Elf_Data	*data;
 	u_int		idx;
 	tnfctl_errcode_t	prexstat = TNFCTL_ERR_NONE;

 	DBG_TNF_PROBE_1(_tnfctl_traverse_object_1, "libtnfctl",
 			"sunw%verbosity 3",
 			tnf_opaque, obj_addr, addr);

 	if (elf_version(EV_CURRENT) == EV_NONE)
 		return (TNFCTL_ERR_INTERNAL);

 	/* open elf descriptor on the fd */
 	elf = elf_begin(objfd, ELF_C_READ, NULL);
 	if (elf == NULL || elf_kind(elf) != ELF_K_ELF) {
 		DBG_TNF_PROBE_0(_tnfctl_traverse_object_2, "libtnfctl",
 			"sunw%verbosity 3; sunw%debug 'not elf object'");
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	/* get the elf header */
 	if ((ehdr = gelf_getehdr(elf, &ehdr_obj)) == NULL) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_object: gelf_getehdr failed\n"));
 		(void) elf_end(elf);
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	if ((ehdr->e_type != ET_EXEC) && (ehdr->e_type != ET_DYN)) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_object: not an "
 			"executable or a shared object\n"));
 		(void) elf_end(elf);
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	/* if an executable file, the base address is 0 */
 	if (ehdr->e_type == ET_EXEC)
 		addr = 0;
 	/* get a pointer to the elf header string table */
 	strs = elf_strptr(elf, ehdr->e_shstrndx, NULL);

 	DBG_TNF_PROBE_1(_tnfctl_traverse_object_3, "libtnfctl",
 			"sunw%verbosity 3",
 			tnf_long, num_sections_found, ehdr->e_shnum);

 	for (idx = 1; idx < ehdr->e_shnum; idx++) {
 		Elf_Scn		*scn;

 		if ((scn = elf_getscn(elf, idx)) == NULL) {
 			DBG((void) fprintf(stderr,
 			    "_tnfctl_traverse_object: elf_getscn failed\n"));
 			prexstat = TNFCTL_ERR_INTERNAL;
 			break;
 		}
 		if ((shdr = gelf_getshdr(scn, &shdr_obj)) == NULL) {
 			DBG((void) fprintf(stderr,
 				"_tnfctl_traverse_obj:gelf_getshdr failed\n"));
 			prexstat = TNFCTL_ERR_INTERNAL;
 			break;
 		}

 		if ((data = elf_getdata(scn, NULL)) == NULL) {
 			DBG((void) fprintf(stderr,
 				"_tnfctl_traverse_obj:gelf_getdata failed\n"));
 			prexstat = TNFCTL_ERR_INTERNAL;
 			break;
 		}
 		/* call the supplied function */
 		prexstat = search_info_p->section_func(elf,
 			strs, scn, shdr, data, addr, search_info_p);
 		if (prexstat)
 			break;
 	}

 	(void) elf_end(elf);

 	return (prexstat);

 }				/* end _tnfctl_traverse_object */


 /*
  * _tnfctl_traverse_rela() - this function traverses a .rela section calling the
  * supplied function on each relocation record.
  */
 /*ARGSUSED*/
 tnfctl_errcode_t
 _tnfctl_traverse_rela(Elf * elf, char *strs, Elf_Scn * rel_scn,
 	GElf_Shdr * rel_shdr, Elf_Data * rel_data, uintptr_t baseaddr,
 	tnfctl_elf_search_t * search_info_p)
 {
 	Elf_Scn		*sym_scn;
 	GElf_Shdr	*sym_shdr, sym_shdr_obj;
 	Elf_Data	*sym_data;
 	Elf3264_Sym	*sym_table;
 	Elf_Scn		*str_scn;
 	GElf_Shdr	*str_shdr, str_shdr_obj;
 	Elf_Data	*str_data;
 	char		*str_table;
 	ulong_t		nrels;
 	uint_t		i;
 	boolean_t	isrela;
 	size_t		rela_sz;
 	char		*ptr;

 	DBG_TNF_PROBE_0(_tnfctl_traverse_rela_1, "libtnfctl",
 				"sunw%verbosity 4");

 	/* bail if this isn't a rela (or rel) section */
 	if (rel_shdr->sh_type == SHT_RELA) {
 		isrela = B_TRUE;
 	} else if (rel_shdr->sh_type == SHT_REL) {
 		isrela = B_FALSE;
 	} else
 		return (TNFCTL_ERR_NONE);

 	/* find the symbol table section associated with this rela section */
 	sym_scn = elf_getscn(elf, rel_shdr->sh_link);
 	if (sym_scn == NULL) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_rela:elf_getscn (sym) failed\n"));
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	sym_shdr = gelf_getshdr(sym_scn, &sym_shdr_obj);
 	if (sym_shdr == NULL) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_rela:gelf_getshdr (sym) failed\n"));
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	sym_data = elf_getdata(sym_scn, NULL);
 	if (sym_data == NULL) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_rela:elf_getdata (sym) failed\n"));
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	sym_table = (Elf3264_Sym *) sym_data->d_buf;

 	/* find the string table associated with the symbol table */
 	str_scn = elf_getscn(elf, sym_shdr->sh_link);
 	if (str_scn == NULL) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_rela:elf_getscn (str) failed\n"));
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	str_shdr = gelf_getshdr(str_scn, &str_shdr_obj);
 	if (str_shdr == NULL) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_rela:gelf_getshdr (str) failed\n"));
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	str_data = elf_getdata(str_scn, NULL);
 	if (str_data == NULL) {
 		DBG((void) fprintf(stderr,
 			"_tnfctl_traverse_rela: elf_getdata (str) failed\n"));
 		return (TNFCTL_ERR_INTERNAL);
 	}
 	str_table = (char *) str_data->d_buf;

 	/* loop over each relocation record */
 	nrels = rel_shdr->sh_size / rel_shdr->sh_entsize;

 	DBG_TNF_PROBE_1(_tnfctl_traverse_rela_2, "libtnfctl",
 			"sunw%verbosity 3",
 			tnf_long, relocations_found, nrels);

 	ptr = rel_data->d_buf;
 	rela_sz = (isrela) ? sizeof (Elf3264_Rela) : sizeof (Elf3264_Rel);
 	for (i = 0; i < nrels; i++, ptr += rela_sz) {
 		Elf3264_Word	syminfo;
 		Elf3264_Sym	*sym;
 		Elf3264_Addr	offset;
 		char		*name;
 		uintptr_t	addr;
 		tnfctl_errcode_t	prexstat;

 		/* decode the r_info field of the relocation record */
 		if (isrela) {
 			Elf3264_Rela	 *rela_p;

 			/*LINTED pointer cast may result in improper alignment*/
 			rela_p = (Elf3264_Rela *) ptr;
 			syminfo = ELF3264_R_SYM(rela_p->r_info);
 			offset = rela_p->r_offset;
 		} else {
 			Elf3264_Rel	  *rel_p;

 			/*LINTED pointer cast may result in improper alignment*/
 			rel_p = (Elf3264_Rel *) ptr;
 			syminfo = ELF3264_R_SYM(rel_p->r_info);
 			offset = rel_p->r_offset;
 		}

 		/* find the associated symbol table entry */
 		if (!syminfo)
 			continue;
 		sym = sym_table + syminfo;

 		/* find the associated string table entry */
 		if (!sym->st_name)
 			continue;
 		name = str_table + sym->st_name;
 		addr = offset + baseaddr;

 		prexstat = search_info_p->record_func(name, addr, ptr,
 							search_info_p);
 		if (prexstat)
 			break;
 	}

 	return (TNFCTL_ERR_NONE);

 }				/* end _tnfctl_traverse_rela */


 /*
  * _tnfctl_traverse_dynsym() - this function traverses a dynsym section calling
  * the supplied function on each symbol.
  */

 /*ARGSUSED*/
 tnfctl_errcode_t
 _tnfctl_traverse_dynsym(Elf * elf,
 			char *elfstrs,
 			Elf_Scn * scn,
 			GElf_Shdr * shdr,
 			Elf_Data * data,
 			uintptr_t baseaddr,
 			tnfctl_elf_search_t * search_info_p)
 {
 	ulong_t		nsyms;
 	int		i;
 	char		*strs;
 	tnfctl_errcode_t	prexstat;

 	Elf3264_Sym	*syms;

 	/* bail if this isn't a dynsym section */
 	if (shdr->sh_type != SHT_DYNSYM)
 		return (TNFCTL_ERR_NONE);
 #if 0
 	printf("### entering _tnfctl_traverse_dynsym...\n");
 #endif
 	syms = data->d_buf;
 	nsyms = shdr->sh_size / shdr->sh_entsize;
 	strs = elf_strptr(elf, shdr->sh_link, 0);

 	DBG_TNF_PROBE_1(_tnfctl_traverse_dynsym_1, "libtnfctl",
 			"sunw%verbosity 3",
 			tnf_long, symbols_found, nsyms);

 	for (i = 0; i < nsyms; i++) {
 		Elf3264_Sym	*sym = &syms[i];
 		char		*name;
 		uintptr_t	addr;

 		name = strs + sym->st_name;
 		addr = baseaddr + sym->st_value;

 #if 0
 		if (name != 0)
 			printf("_tnfctl_traverse_dynsym: name = %s\n", name);
 		else
 			printf("_tnfctl_traverse_dynsym: name is 0\n");
 #endif
 		prexstat = search_info_p->record_func(name,
 			addr, sym, search_info_p);
 		if (prexstat)
 			break;
 	}
 #if 0
 	printf("### leaving _tnfctl_traverse_dynsym...\n");
 #endif
 	return (prexstat);

 }				/* end _tnfctl_traverse_dynsym */
	/*
	* CDDL HEADER START
	*
	* The contents of this file are subject to the terms of the
	* Common Development and Distribution License, Version 1.0 only
	* (the "License"). You may not use this file except in compliance
	* with the License.
	*
	* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
	* or http://www.opensolaris.org/os/licensing.
	* See the License for the specific language governing permissions
	* and limitations under the License.
	*
	* When distributing Covered Code, include this CDDL HEADER in each
	* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
	* If applicable, add the following below this CDDL HEADER, with the
	* fields enclosed by brackets "[]" replaced with your own identifying
	* information: Portions Copyright [yyyy] [name of copyright owner]
	*
	* CDDL HEADER END
	*/
	/*
	* Copyright (c) 1994, by Sun Microsytems, Inc.
	*/

	#pragma ident "%Z%%M% %I% %E% SMI"

	/*
	* Generic functions that know how to traverse elf sections in an object.
	* Also functions that know how to traverse records in a section.
	*
	*/

	#include <string.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <errno.h>
	#include <sys/procfs.h>
	#include <sys/stat.h>

	#include "tnfctl_int.h"
	#include "dbg.h"


	/*
	* _tnfctl_traverse_object() - traverses all of the elf sections in an object,
	* calling the supplied function on each.
	*/
	tnfctl_errcode_t
	_tnfctl_traverse_object(int objfd, uintptr_t addr,
	tnfctl_elf_search_t *search_info_p)
	{
	Elf *elf;
	GElf_Ehdr *ehdr, ehdr_obj;
	char *strs;
	GElf_Shdr *shdr, shdr_obj;
	Elf_Data *data;
	u_int idx;
	tnfctl_errcode_t prexstat = TNFCTL_ERR_NONE;

	DBG_TNF_PROBE_1(_tnfctl_traverse_object_1, "libtnfctl",
	"sunw%verbosity 3",
	tnf_opaque, obj_addr, addr);

	if (elf_version(EV_CURRENT) == EV_NONE)
	return (TNFCTL_ERR_INTERNAL);

	/* open elf descriptor on the fd */
	elf = elf_begin(objfd, ELF_C_READ, NULL);
	if (elf == NULL \|\| elf_kind(elf) != ELF_K_ELF) {
	DBG_TNF_PROBE_0(_tnfctl_traverse_object_2, "libtnfctl",
	"sunw%verbosity 3; sunw%debug 'not elf object'");
	return (TNFCTL_ERR_INTERNAL);
	}
	/* get the elf header */
	if ((ehdr = gelf_getehdr(elf, &ehdr_obj)) == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_object: gelf_getehdr failed\n"));
	(void) elf_end(elf);
	return (TNFCTL_ERR_INTERNAL);
	}
	if ((ehdr->e_type != ET_EXEC) && (ehdr->e_type != ET_DYN)) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_object: not an "
	"executable or a shared object\n"));
	(void) elf_end(elf);
	return (TNFCTL_ERR_INTERNAL);
	}
	/* if an executable file, the base address is 0 */
	if (ehdr->e_type == ET_EXEC)
	addr = 0;
	/* get a pointer to the elf header string table */
	strs = elf_strptr(elf, ehdr->e_shstrndx, NULL);

	DBG_TNF_PROBE_1(_tnfctl_traverse_object_3, "libtnfctl",
	"sunw%verbosity 3",
	tnf_long, num_sections_found, ehdr->e_shnum);

	for (idx = 1; idx < ehdr->e_shnum; idx++) {
	Elf_Scn *scn;

	if ((scn = elf_getscn(elf, idx)) == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_object: elf_getscn failed\n"));
	prexstat = TNFCTL_ERR_INTERNAL;
	break;
	}
	if ((shdr = gelf_getshdr(scn, &shdr_obj)) == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_obj:gelf_getshdr failed\n"));
	prexstat = TNFCTL_ERR_INTERNAL;
	break;
	}

	if ((data = elf_getdata(scn, NULL)) == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_obj:gelf_getdata failed\n"));
	prexstat = TNFCTL_ERR_INTERNAL;
	break;
	}
	/* call the supplied function */
	prexstat = search_info_p->section_func(elf,
	strs, scn, shdr, data, addr, search_info_p);
	if (prexstat)
	break;
	}

	(void) elf_end(elf);

	return (prexstat);

	} /* end _tnfctl_traverse_object */


	/*
	* _tnfctl_traverse_rela() - this function traverses a .rela section calling the
	* supplied function on each relocation record.
	*/
	/ARGSUSED/
	tnfctl_errcode_t
	_tnfctl_traverse_rela(Elf * elf, char strs, Elf_Scn rel_scn,
	GElf_Shdr * rel_shdr, Elf_Data * rel_data, uintptr_t baseaddr,
	tnfctl_elf_search_t * search_info_p)
	{
	Elf_Scn *sym_scn;
	GElf_Shdr *sym_shdr, sym_shdr_obj;
	Elf_Data *sym_data;
	Elf3264_Sym *sym_table;
	Elf_Scn *str_scn;
	GElf_Shdr *str_shdr, str_shdr_obj;
	Elf_Data *str_data;
	char *str_table;
	ulong_t nrels;
	uint_t i;
	boolean_t isrela;
	size_t rela_sz;
	char *ptr;

	DBG_TNF_PROBE_0(_tnfctl_traverse_rela_1, "libtnfctl",
	"sunw%verbosity 4");

	/* bail if this isn't a rela (or rel) section */
	if (rel_shdr->sh_type == SHT_RELA) {
	isrela = B_TRUE;
	} else if (rel_shdr->sh_type == SHT_REL) {
	isrela = B_FALSE;
	} else
	return (TNFCTL_ERR_NONE);

	/* find the symbol table section associated with this rela section */
	sym_scn = elf_getscn(elf, rel_shdr->sh_link);
	if (sym_scn == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_rela:elf_getscn (sym) failed\n"));
	return (TNFCTL_ERR_INTERNAL);
	}
	sym_shdr = gelf_getshdr(sym_scn, &sym_shdr_obj);
	if (sym_shdr == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_rela:gelf_getshdr (sym) failed\n"));
	return (TNFCTL_ERR_INTERNAL);
	}
	sym_data = elf_getdata(sym_scn, NULL);
	if (sym_data == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_rela:elf_getdata (sym) failed\n"));
	return (TNFCTL_ERR_INTERNAL);
	}
	sym_table = (Elf3264_Sym *) sym_data->d_buf;

	/* find the string table associated with the symbol table */
	str_scn = elf_getscn(elf, sym_shdr->sh_link);
	if (str_scn == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_rela:elf_getscn (str) failed\n"));
	return (TNFCTL_ERR_INTERNAL);
	}
	str_shdr = gelf_getshdr(str_scn, &str_shdr_obj);
	if (str_shdr == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_rela:gelf_getshdr (str) failed\n"));
	return (TNFCTL_ERR_INTERNAL);
	}
	str_data = elf_getdata(str_scn, NULL);
	if (str_data == NULL) {
	DBG((void) fprintf(stderr,
	"_tnfctl_traverse_rela: elf_getdata (str) failed\n"));
	return (TNFCTL_ERR_INTERNAL);
	}
	str_table = (char *) str_data->d_buf;

	/* loop over each relocation record */
	nrels = rel_shdr->sh_size / rel_shdr->sh_entsize;

	DBG_TNF_PROBE_1(_tnfctl_traverse_rela_2, "libtnfctl",
	"sunw%verbosity 3",
	tnf_long, relocations_found, nrels);

	ptr = rel_data->d_buf;
	rela_sz = (isrela) ? sizeof (Elf3264_Rela) : sizeof (Elf3264_Rel);
	for (i = 0; i < nrels; i++, ptr += rela_sz) {
	Elf3264_Word syminfo;
	Elf3264_Sym *sym;
	Elf3264_Addr offset;
	char *name;
	uintptr_t addr;
	tnfctl_errcode_t prexstat;

	/* decode the r_info field of the relocation record */
	if (isrela) {
	Elf3264_Rela *rela_p;

	/LINTED pointer cast may result in improper alignment/
	rela_p = (Elf3264_Rela *) ptr;
	syminfo = ELF3264_R_SYM(rela_p->r_info);
	offset = rela_p->r_offset;
	} else {
	Elf3264_Rel *rel_p;

	/LINTED pointer cast may result in improper alignment/
	rel_p = (Elf3264_Rel *) ptr;
	syminfo = ELF3264_R_SYM(rel_p->r_info);
	offset = rel_p->r_offset;
	}

	/* find the associated symbol table entry */
	if (!syminfo)
	continue;
	sym = sym_table + syminfo;

	/* find the associated string table entry */
	if (!sym->st_name)
	continue;
	name = str_table + sym->st_name;
	addr = offset + baseaddr;

	prexstat = search_info_p->record_func(name, addr, ptr,
	search_info_p);
	if (prexstat)
	break;
	}

	return (TNFCTL_ERR_NONE);

	} /* end _tnfctl_traverse_rela */


	/*
	* _tnfctl_traverse_dynsym() - this function traverses a dynsym section calling
	* the supplied function on each symbol.
	*/

	/ARGSUSED/
	tnfctl_errcode_t
	_tnfctl_traverse_dynsym(Elf * elf,
	char *elfstrs,
	Elf_Scn * scn,
	GElf_Shdr * shdr,
	Elf_Data * data,
	uintptr_t baseaddr,
	tnfctl_elf_search_t * search_info_p)
	{
	ulong_t nsyms;
	int i;
	char *strs;
	tnfctl_errcode_t prexstat;

	Elf3264_Sym *syms;

	/* bail if this isn't a dynsym section */
	if (shdr->sh_type != SHT_DYNSYM)
	return (TNFCTL_ERR_NONE);
	#if 0
	printf("### entering _tnfctl_traverse_dynsym...\n");
	#endif
	syms = data->d_buf;
	nsyms = shdr->sh_size / shdr->sh_entsize;
	strs = elf_strptr(elf, shdr->sh_link, 0);

	DBG_TNF_PROBE_1(_tnfctl_traverse_dynsym_1, "libtnfctl",
	"sunw%verbosity 3",
	tnf_long, symbols_found, nsyms);

	for (i = 0; i < nsyms; i++) {
	Elf3264_Sym *sym = &syms[i];
	char *name;
	uintptr_t addr;

	name = strs + sym->st_name;
	addr = baseaddr + sym->st_value;

	#if 0
	if (name != 0)
	printf("_tnfctl_traverse_dynsym: name = %s\n", name);
	else
	printf("_tnfctl_traverse_dynsym: name is 0\n");
	#endif
	prexstat = search_info_p->record_func(name,
	addr, sym, search_info_p);
	if (prexstat)
	break;
	}
	#if 0
	printf("### leaving _tnfctl_traverse_dynsym...\n");
	#endif
	return (prexstat);

	} /* end _tnfctl_traverse_dynsym */