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/*
* 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 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/ksyms.h>
#include <sys/systm.h>
#include <sys/sysmacros.h>
#include <sys/debug.h>
#include <sys/cmn_err.h>
static const char ksyms_shstrtab[] = "\0.symtab\0.strtab\0.shstrtab\0";
#define KSHDR_NULL 0
#define KSHDR_SYMTAB 1
#define KSHDR_STRTAB 2
#define KSHDR_SHSTRTAB 3
#define KSHDR_NUM 4
typedef struct ksyms_header {
Ehdr elf_hdr; /* Elf file header */
Phdr text_phdr; /* text program header */
Phdr data_phdr; /* data program header */
Shdr shdr[KSHDR_NUM]; /* section headers */
char shstrings[sizeof (ksyms_shstrtab)]; /* shstrtab strings */
} ksyms_header_t;
#define KW_HEADER 0x1
#define KW_LOCALS 0x2
#define KW_GLOBALS 0x4
#define KW_STRINGS 0x8
typedef struct ksyms_walkinfo {
void (*kw_emit)(const void *, void *, size_t);
char *kw_target;
ssize_t kw_resid;
ssize_t kw_totalsize;
int kw_actions;
size_t kw_size[KW_STRINGS + 1];
} ksyms_walkinfo_t;
krwlock_t ksyms_lock;
vmem_t *ksyms_arena;
static void
ksyms_emit(ksyms_walkinfo_t *kwp, void *src, size_t size, int action)
{
if (kwp->kw_actions & action) {
if ((kwp->kw_resid -= size) >= 0)
kwp->kw_emit(src, kwp->kw_target, size);
kwp->kw_totalsize += size;
}
kwp->kw_size[action] += size;
}
/*ARGSUSED*/
static void
ksyms_walk_one(void *arg, void *base, size_t size)
{
ksyms_walkinfo_t *kwp = arg;
Shdr *symhdr = base;
Shdr *strhdr = symhdr + symhdr->sh_link;
size_t symsize = symhdr->sh_entsize;
size_t nsyms = symhdr->sh_size / symsize;
char *strings = (char *)strhdr->sh_addr;
int i;
for (i = 1; i < nsyms; i++) {
Sym *sym = (Sym *)(symhdr->sh_addr + i * symsize);
Sym tmp = *sym;
char *name = strings + sym->st_name;
tmp.st_name = kwp->kw_size[KW_STRINGS];
tmp.st_shndx = SHN_ABS;
ksyms_emit(kwp, &tmp, sizeof (Sym),
ELF_ST_BIND(sym->st_info) == STB_LOCAL ?
KW_LOCALS : KW_GLOBALS);
ksyms_emit(kwp, name, strlen(name) + 1, KW_STRINGS);
}
}
static ssize_t
ksyms_walk(ksyms_walkinfo_t *kwp, void *target, ssize_t resid,
void (*emit)(const void *, void *, size_t), void *src, int actions)
{
Sym tmp;
bzero(kwp, sizeof (ksyms_walkinfo_t));
kwp->kw_emit = emit;
kwp->kw_target = target;
kwp->kw_resid = resid;
kwp->kw_actions = actions;
ksyms_emit(kwp, src, sizeof (ksyms_header_t), KW_HEADER);
/*
* The first symbol table entry is all zeroes; it's unused
* because index 0 marks the end of symbol hash chains.
*/
bzero(&tmp, sizeof (Sym));
ksyms_emit(kwp, &tmp, sizeof (Sym), KW_LOCALS);
ksyms_emit(kwp, &tmp, 1, KW_STRINGS);
vmem_walk(ksyms_arena, VMEM_ALLOC, ksyms_walk_one, kwp);
return (kwp->kw_totalsize);
}
size_t
ksyms_snapshot(void (*emit)(const void *, void *, size_t),
void *buf, size_t len)
{
ksyms_walkinfo_t kw;
ksyms_header_t hdr;
ssize_t size = 0, bufsize = len;
Shdr *shp;
rw_enter(&ksyms_lock, RW_READER);
/*
* Compute the size of the header, locals, globals, and strings.
*/
(void) ksyms_walk(&kw, NULL, 0, NULL, NULL,
KW_HEADER | KW_LOCALS | KW_GLOBALS | KW_STRINGS);
/*
* Construct the ELF header.
*/
bzero(&hdr, sizeof (hdr));
hdr.elf_hdr = ((struct module *)modules.mod_mp)->hdr;
hdr.elf_hdr.e_phoff = offsetof(ksyms_header_t, text_phdr);
hdr.elf_hdr.e_shoff = offsetof(ksyms_header_t, shdr);
hdr.elf_hdr.e_phnum = 2;
hdr.elf_hdr.e_shnum = KSHDR_NUM;
hdr.elf_hdr.e_shstrndx = KSHDR_SHSTRTAB;
hdr.text_phdr.p_type = PT_LOAD;
hdr.text_phdr.p_vaddr = (Addr)s_text;
hdr.text_phdr.p_memsz = (Word)(e_text - s_text);
hdr.text_phdr.p_flags = PF_R | PF_X;
hdr.data_phdr.p_type = PT_LOAD;
hdr.data_phdr.p_vaddr = (Addr)s_data;
hdr.data_phdr.p_memsz = (Word)(e_data - s_data);
hdr.data_phdr.p_flags = PF_R | PF_W | PF_X;
shp = &hdr.shdr[KSHDR_SYMTAB];
shp->sh_name = 1; /* ksyms_shstrtab[1] = ".symtab" */
shp->sh_type = SHT_SYMTAB;
shp->sh_offset = kw.kw_size[KW_HEADER];
shp->sh_size = kw.kw_size[KW_LOCALS] + kw.kw_size[KW_GLOBALS];
shp->sh_link = KSHDR_STRTAB;
shp->sh_info = kw.kw_size[KW_LOCALS] / sizeof (Sym);
shp->sh_addralign = sizeof (Addr);
shp->sh_entsize = sizeof (Sym);
shp = &hdr.shdr[KSHDR_STRTAB];
shp->sh_name = 9; /* ksyms_shstrtab[9] = ".strtab" */
shp->sh_type = SHT_STRTAB;
shp->sh_offset = kw.kw_size[KW_HEADER] +
kw.kw_size[KW_LOCALS] + kw.kw_size[KW_GLOBALS];
shp->sh_size = kw.kw_size[KW_STRINGS];
shp->sh_addralign = 1;
shp = &hdr.shdr[KSHDR_SHSTRTAB];
shp->sh_name = 17; /* ksyms_shstrtab[17] = ".shstrtab" */
shp->sh_type = SHT_STRTAB;
shp->sh_offset = offsetof(ksyms_header_t, shstrings);
shp->sh_size = sizeof (ksyms_shstrtab);
shp->sh_addralign = 1;
bcopy(ksyms_shstrtab, hdr.shstrings, sizeof (ksyms_shstrtab));
/*
* Emit the symbol table.
*/
size += ksyms_walk(&kw, buf, (bufsize - size), emit, &hdr,
KW_HEADER);
size += ksyms_walk(&kw, buf, (bufsize - size), emit,
NULL, KW_LOCALS);
size += ksyms_walk(&kw, buf, (bufsize - size), emit,
NULL, KW_GLOBALS);
size += ksyms_walk(&kw, buf, (bufsize - size), emit, NULL,
KW_STRINGS);
rw_exit(&ksyms_lock);
return ((size_t)size);
}
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