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Diffstat (limited to 'cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c')
-rw-r--r--cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c527
1 files changed, 527 insertions, 0 deletions
diff --git a/cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c b/cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c
new file mode 100644
index 000000000000..0df44cfda938
--- /dev/null
+++ b/cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c
@@ -0,0 +1,527 @@
+/*
+ * 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 2003 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident "%Z%%M% %I% %E% SMI"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <sys/zmod.h>
+#include <ctf_impl.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#if defined(sun)
+#include <dlfcn.h>
+#else
+#include <zlib.h>
+#endif
+#include <gelf.h>
+
+#if defined(sun)
+#ifdef _LP64
+static const char *_libctf_zlib = "/usr/lib/64/libz.so";
+#else
+static const char *_libctf_zlib = "/usr/lib/libz.so";
+#endif
+#endif
+
+static struct {
+ int (*z_uncompress)(uchar_t *, ulong_t *, const uchar_t *, ulong_t);
+ const char *(*z_error)(int);
+ void *z_dlp;
+} zlib;
+
+static size_t _PAGESIZE;
+static size_t _PAGEMASK;
+
+#if defined(sun)
+#pragma init(_libctf_init)
+#else
+void _libctf_init(void) __attribute__ ((constructor));
+#endif
+void
+_libctf_init(void)
+{
+#if defined(sun)
+ const char *p = getenv("LIBCTF_DECOMPRESSOR");
+
+ if (p != NULL)
+ _libctf_zlib = p; /* use alternate decompression library */
+#endif
+
+ _libctf_debug = getenv("LIBCTF_DEBUG") != NULL;
+
+ _PAGESIZE = getpagesize();
+ _PAGEMASK = ~(_PAGESIZE - 1);
+}
+
+/*
+ * Attempt to dlopen the decompression library and locate the symbols of
+ * interest that we will need to call. This information in cached so
+ * that multiple calls to ctf_bufopen() do not need to reopen the library.
+ */
+void *
+ctf_zopen(int *errp)
+{
+#if defined(sun)
+ ctf_dprintf("decompressing CTF data using %s\n", _libctf_zlib);
+
+ if (zlib.z_dlp != NULL)
+ return (zlib.z_dlp); /* library is already loaded */
+
+ if (access(_libctf_zlib, R_OK) == -1)
+ return (ctf_set_open_errno(errp, ECTF_ZMISSING));
+
+ if ((zlib.z_dlp = dlopen(_libctf_zlib, RTLD_LAZY | RTLD_LOCAL)) == NULL)
+ return (ctf_set_open_errno(errp, ECTF_ZINIT));
+
+ zlib.z_uncompress = (int (*)(uchar_t *, ulong_t *, const uchar_t *, ulong_t)) dlsym(zlib.z_dlp, "uncompress");
+ zlib.z_error = (const char *(*)(int)) dlsym(zlib.z_dlp, "zError");
+
+ if (zlib.z_uncompress == NULL || zlib.z_error == NULL) {
+ (void) dlclose(zlib.z_dlp);
+ bzero(&zlib, sizeof (zlib));
+ return (ctf_set_open_errno(errp, ECTF_ZINIT));
+ }
+#else
+ zlib.z_uncompress = uncompress;
+ zlib.z_error = zError;
+
+ /* Dummy return variable as 'no error' */
+ zlib.z_dlp = (void *) (uintptr_t) 1;
+#endif
+
+ return (zlib.z_dlp);
+}
+
+/*
+ * The ctf_bufopen() routine calls these subroutines, defined by <sys/zmod.h>,
+ * which we then patch through to the functions in the decompression library.
+ */
+int
+z_uncompress(void *dst, size_t *dstlen, const void *src, size_t srclen)
+{
+ return (zlib.z_uncompress(dst, (ulong_t *)dstlen, src, srclen));
+}
+
+const char *
+z_strerror(int err)
+{
+ return (zlib.z_error(err));
+}
+
+/*
+ * Convert a 32-bit ELF file header into GElf.
+ */
+static void
+ehdr_to_gelf(const Elf32_Ehdr *src, GElf_Ehdr *dst)
+{
+ bcopy(src->e_ident, dst->e_ident, EI_NIDENT);
+ dst->e_type = src->e_type;
+ dst->e_machine = src->e_machine;
+ dst->e_version = src->e_version;
+ dst->e_entry = (Elf64_Addr)src->e_entry;
+ dst->e_phoff = (Elf64_Off)src->e_phoff;
+ dst->e_shoff = (Elf64_Off)src->e_shoff;
+ dst->e_flags = src->e_flags;
+ dst->e_ehsize = src->e_ehsize;
+ dst->e_phentsize = src->e_phentsize;
+ dst->e_phnum = src->e_phnum;
+ dst->e_shentsize = src->e_shentsize;
+ dst->e_shnum = src->e_shnum;
+ dst->e_shstrndx = src->e_shstrndx;
+}
+
+/*
+ * Convert a 32-bit ELF section header into GElf.
+ */
+static void
+shdr_to_gelf(const Elf32_Shdr *src, GElf_Shdr *dst)
+{
+ dst->sh_name = src->sh_name;
+ dst->sh_type = src->sh_type;
+ dst->sh_flags = src->sh_flags;
+ dst->sh_addr = src->sh_addr;
+ dst->sh_offset = src->sh_offset;
+ dst->sh_size = src->sh_size;
+ dst->sh_link = src->sh_link;
+ dst->sh_info = src->sh_info;
+ dst->sh_addralign = src->sh_addralign;
+ dst->sh_entsize = src->sh_entsize;
+}
+
+/*
+ * In order to mmap a section from the ELF file, we must round down sh_offset
+ * to the previous page boundary, and mmap the surrounding page. We store
+ * the pointer to the start of the actual section data back into sp->cts_data.
+ */
+const void *
+ctf_sect_mmap(ctf_sect_t *sp, int fd)
+{
+ size_t pageoff = sp->cts_offset & ~_PAGEMASK;
+
+ caddr_t base = mmap64(NULL, sp->cts_size + pageoff, PROT_READ,
+ MAP_PRIVATE, fd, sp->cts_offset & _PAGEMASK);
+
+ if (base != MAP_FAILED)
+ sp->cts_data = base + pageoff;
+
+ return (base);
+}
+
+/*
+ * Since sp->cts_data has the adjusted offset, we have to again round down
+ * to get the actual mmap address and round up to get the size.
+ */
+void
+ctf_sect_munmap(const ctf_sect_t *sp)
+{
+ uintptr_t addr = (uintptr_t)sp->cts_data;
+ uintptr_t pageoff = addr & ~_PAGEMASK;
+
+ (void) munmap((void *)(addr - pageoff), sp->cts_size + pageoff);
+}
+
+/*
+ * Open the specified file descriptor and return a pointer to a CTF container.
+ * The file can be either an ELF file or raw CTF file. The caller is
+ * responsible for closing the file descriptor when it is no longer needed.
+ */
+ctf_file_t *
+ctf_fdopen(int fd, int *errp)
+{
+ ctf_sect_t ctfsect, symsect, strsect;
+ ctf_file_t *fp = NULL;
+ size_t shstrndx, shnum;
+
+ struct stat64 st;
+ ssize_t nbytes;
+
+ union {
+ ctf_preamble_t ctf;
+ Elf32_Ehdr e32;
+ GElf_Ehdr e64;
+ } hdr;
+
+ bzero(&ctfsect, sizeof (ctf_sect_t));
+ bzero(&symsect, sizeof (ctf_sect_t));
+ bzero(&strsect, sizeof (ctf_sect_t));
+ bzero(&hdr.ctf, sizeof (hdr));
+
+ if (fstat64(fd, &st) == -1)
+ return (ctf_set_open_errno(errp, errno));
+
+ if ((nbytes = pread64(fd, &hdr.ctf, sizeof (hdr), 0)) <= 0)
+ return (ctf_set_open_errno(errp, nbytes < 0? errno : ECTF_FMT));
+
+ /*
+ * If we have read enough bytes to form a CTF header and the magic
+ * string matches, attempt to interpret the file as raw CTF.
+ */
+ if (nbytes >= (ssize_t) sizeof (ctf_preamble_t) &&
+ hdr.ctf.ctp_magic == CTF_MAGIC) {
+ if (hdr.ctf.ctp_version > CTF_VERSION)
+ return (ctf_set_open_errno(errp, ECTF_CTFVERS));
+
+ ctfsect.cts_data = mmap64(NULL, st.st_size, PROT_READ,
+ MAP_PRIVATE, fd, 0);
+
+ if (ctfsect.cts_data == MAP_FAILED)
+ return (ctf_set_open_errno(errp, errno));
+
+ ctfsect.cts_name = _CTF_SECTION;
+ ctfsect.cts_type = SHT_PROGBITS;
+ ctfsect.cts_flags = SHF_ALLOC;
+ ctfsect.cts_size = (size_t)st.st_size;
+ ctfsect.cts_entsize = 1;
+ ctfsect.cts_offset = 0;
+
+ if ((fp = ctf_bufopen(&ctfsect, NULL, NULL, errp)) == NULL)
+ ctf_sect_munmap(&ctfsect);
+
+ return (fp);
+ }
+
+ /*
+ * If we have read enough bytes to form an ELF header and the magic
+ * string matches, attempt to interpret the file as an ELF file. We
+ * do our own largefile ELF processing, and convert everything to
+ * GElf structures so that clients can operate on any data model.
+ */
+ if (nbytes >= (ssize_t) sizeof (Elf32_Ehdr) &&
+ bcmp(&hdr.e32.e_ident[EI_MAG0], ELFMAG, SELFMAG) == 0) {
+#ifdef _BIG_ENDIAN
+ uchar_t order = ELFDATA2MSB;
+#else
+ uchar_t order = ELFDATA2LSB;
+#endif
+ GElf_Shdr *sp;
+
+ void *strs_map;
+ size_t strs_mapsz, i;
+ char *strs;
+
+ if (hdr.e32.e_ident[EI_DATA] != order)
+ return (ctf_set_open_errno(errp, ECTF_ENDIAN));
+ if (hdr.e32.e_version != EV_CURRENT)
+ return (ctf_set_open_errno(errp, ECTF_ELFVERS));
+
+ if (hdr.e32.e_ident[EI_CLASS] == ELFCLASS64) {
+ if (nbytes < (ssize_t) sizeof (GElf_Ehdr))
+ return (ctf_set_open_errno(errp, ECTF_FMT));
+ } else {
+ Elf32_Ehdr e32 = hdr.e32;
+ ehdr_to_gelf(&e32, &hdr.e64);
+ }
+
+ shnum = hdr.e64.e_shnum;
+ shstrndx = hdr.e64.e_shstrndx;
+
+ /* Extended ELF sections */
+ if ((shstrndx == SHN_XINDEX) || (shnum == 0)) {
+ if (hdr.e32.e_ident[EI_CLASS] == ELFCLASS32) {
+ Elf32_Shdr x32;
+
+ if (pread64(fd, &x32, sizeof (x32),
+ hdr.e64.e_shoff) != sizeof (x32))
+ return (ctf_set_open_errno(errp,
+ errno));
+
+ shnum = x32.sh_size;
+ shstrndx = x32.sh_link;
+ } else {
+ Elf64_Shdr x64;
+
+ if (pread64(fd, &x64, sizeof (x64),
+ hdr.e64.e_shoff) != sizeof (x64))
+ return (ctf_set_open_errno(errp,
+ errno));
+
+ shnum = x64.sh_size;
+ shstrndx = x64.sh_link;
+ }
+ }
+
+ if (shstrndx >= shnum)
+ return (ctf_set_open_errno(errp, ECTF_CORRUPT));
+
+ nbytes = sizeof (GElf_Shdr) * shnum;
+
+ if ((sp = malloc(nbytes)) == NULL)
+ return (ctf_set_open_errno(errp, errno));
+
+ /*
+ * Read in and convert to GElf the array of Shdr structures
+ * from e_shoff so we can locate sections of interest.
+ */
+ if (hdr.e32.e_ident[EI_CLASS] == ELFCLASS32) {
+ Elf32_Shdr *sp32;
+
+ nbytes = sizeof (Elf32_Shdr) * shnum;
+
+ if ((sp32 = malloc(nbytes)) == NULL || pread64(fd,
+ sp32, nbytes, hdr.e64.e_shoff) != nbytes) {
+ free(sp);
+ return (ctf_set_open_errno(errp, errno));
+ }
+
+ for (i = 0; i < shnum; i++)
+ shdr_to_gelf(&sp32[i], &sp[i]);
+
+ free(sp32);
+
+ } else if (pread64(fd, sp, nbytes, hdr.e64.e_shoff) != nbytes) {
+ free(sp);
+ return (ctf_set_open_errno(errp, errno));
+ }
+
+ /*
+ * Now mmap the section header strings section so that we can
+ * perform string comparison on the section names.
+ */
+ strs_mapsz = sp[shstrndx].sh_size +
+ (sp[shstrndx].sh_offset & ~_PAGEMASK);
+
+ strs_map = mmap64(NULL, strs_mapsz, PROT_READ, MAP_PRIVATE,
+ fd, sp[shstrndx].sh_offset & _PAGEMASK);
+
+ strs = (char *)strs_map +
+ (sp[shstrndx].sh_offset & ~_PAGEMASK);
+
+ if (strs_map == MAP_FAILED) {
+ free(sp);
+ return (ctf_set_open_errno(errp, ECTF_MMAP));
+ }
+
+ /*
+ * Iterate over the section header array looking for the CTF
+ * section and symbol table. The strtab is linked to symtab.
+ */
+ for (i = 0; i < shnum; i++) {
+ const GElf_Shdr *shp = &sp[i];
+ const GElf_Shdr *lhp = &sp[shp->sh_link];
+
+ if (shp->sh_link >= shnum)
+ continue; /* corrupt sh_link field */
+
+ if (shp->sh_name >= sp[shstrndx].sh_size ||
+ lhp->sh_name >= sp[shstrndx].sh_size)
+ continue; /* corrupt sh_name field */
+
+ if (shp->sh_type == SHT_PROGBITS &&
+ strcmp(strs + shp->sh_name, _CTF_SECTION) == 0) {
+ ctfsect.cts_name = strs + shp->sh_name;
+ ctfsect.cts_type = shp->sh_type;
+ ctfsect.cts_flags = shp->sh_flags;
+ ctfsect.cts_size = shp->sh_size;
+ ctfsect.cts_entsize = shp->sh_entsize;
+ ctfsect.cts_offset = (off64_t)shp->sh_offset;
+
+ } else if (shp->sh_type == SHT_SYMTAB) {
+ symsect.cts_name = strs + shp->sh_name;
+ symsect.cts_type = shp->sh_type;
+ symsect.cts_flags = shp->sh_flags;
+ symsect.cts_size = shp->sh_size;
+ symsect.cts_entsize = shp->sh_entsize;
+ symsect.cts_offset = (off64_t)shp->sh_offset;
+
+ strsect.cts_name = strs + lhp->sh_name;
+ strsect.cts_type = lhp->sh_type;
+ strsect.cts_flags = lhp->sh_flags;
+ strsect.cts_size = lhp->sh_size;
+ strsect.cts_entsize = lhp->sh_entsize;
+ strsect.cts_offset = (off64_t)lhp->sh_offset;
+ }
+ }
+
+ free(sp); /* free section header array */
+
+ if (ctfsect.cts_type == SHT_NULL) {
+ (void) munmap(strs_map, strs_mapsz);
+ return (ctf_set_open_errno(errp, ECTF_NOCTFDATA));
+ }
+
+ /*
+ * Now mmap the CTF data, symtab, and strtab sections and
+ * call ctf_bufopen() to do the rest of the work.
+ */
+ if (ctf_sect_mmap(&ctfsect, fd) == MAP_FAILED) {
+ (void) munmap(strs_map, strs_mapsz);
+ return (ctf_set_open_errno(errp, ECTF_MMAP));
+ }
+
+ if (symsect.cts_type != SHT_NULL &&
+ strsect.cts_type != SHT_NULL) {
+ if (ctf_sect_mmap(&symsect, fd) == MAP_FAILED ||
+ ctf_sect_mmap(&strsect, fd) == MAP_FAILED) {
+ (void) ctf_set_open_errno(errp, ECTF_MMAP);
+ goto bad; /* unmap all and abort */
+ }
+ fp = ctf_bufopen(&ctfsect, &symsect, &strsect, errp);
+ } else
+ fp = ctf_bufopen(&ctfsect, NULL, NULL, errp);
+bad:
+ if (fp == NULL) {
+ ctf_sect_munmap(&ctfsect);
+ ctf_sect_munmap(&symsect);
+ ctf_sect_munmap(&strsect);
+ } else
+ fp->ctf_flags |= LCTF_MMAP;
+
+ (void) munmap(strs_map, strs_mapsz);
+ return (fp);
+ }
+
+ return (ctf_set_open_errno(errp, ECTF_FMT));
+}
+
+/*
+ * Open the specified file and return a pointer to a CTF container. The file
+ * can be either an ELF file or raw CTF file. This is just a convenient
+ * wrapper around ctf_fdopen() for callers.
+ */
+ctf_file_t *
+ctf_open(const char *filename, int *errp)
+{
+ ctf_file_t *fp;
+ int fd;
+
+ if ((fd = open64(filename, O_RDONLY)) == -1) {
+ if (errp != NULL)
+ *errp = errno;
+ return (NULL);
+ }
+
+ fp = ctf_fdopen(fd, errp);
+ (void) close(fd);
+ return (fp);
+}
+
+/*
+ * Write the uncompressed CTF data stream to the specified file descriptor.
+ * This is useful for saving the results of dynamic CTF containers.
+ */
+int
+ctf_write(ctf_file_t *fp, int fd)
+{
+ const uchar_t *buf = fp->ctf_base;
+ ssize_t resid = fp->ctf_size;
+ ssize_t len;
+
+ while (resid != 0) {
+ if ((len = write(fd, buf, resid)) <= 0)
+ return (ctf_set_errno(fp, errno));
+ resid -= len;
+ buf += len;
+ }
+
+ return (0);
+}
+
+/*
+ * Set the CTF library client version to the specified version. If version is
+ * zero, we just return the default library version number.
+ */
+int
+ctf_version(int version)
+{
+ if (version < 0) {
+ errno = EINVAL;
+ return (-1);
+ }
+
+ if (version > 0) {
+ if (version > CTF_VERSION) {
+ errno = ENOTSUP;
+ return (-1);
+ }
+ ctf_dprintf("ctf_version: client using version %d\n", version);
+ _libctf_version = version;
+ }
+
+ return (_libctf_version);
+}