diff options
Diffstat (limited to 'bfd/elf-attrs.c')
| -rw-r--r-- | bfd/elf-attrs.c | 628 |
1 files changed, 628 insertions, 0 deletions
diff --git a/bfd/elf-attrs.c b/bfd/elf-attrs.c new file mode 100644 index 0000000..d1a64f4 --- /dev/null +++ b/bfd/elf-attrs.c @@ -0,0 +1,628 @@ +/* ELF attributes support (based on ARM EABI attributes). + Copyright 2005, 2006, 2007 + Free Software Foundation, Inc. + + This file is part of BFD, the Binary File Descriptor library. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ + +#include "sysdep.h" +#include "bfd.h" +#include "libiberty.h" +#include "libbfd.h" +#include "elf-bfd.h" + +/* Return the number of bytes needed by I in uleb128 format. */ +static int +uleb128_size (unsigned int i) +{ + int size; + size = 1; + while (i >= 0x80) + { + i >>= 7; + size++; + } + return size; +} + +/* Return TRUE if the attribute has the default value (0/""). */ +static bfd_boolean +is_default_attr (obj_attribute *attr) +{ + if ((attr->type & 1) && attr->i != 0) + return FALSE; + if ((attr->type & 2) && attr->s && *attr->s) + return FALSE; + + return TRUE; +} + +/* Return the size of a single attribute. */ +static bfd_vma +obj_attr_size (int tag, obj_attribute *attr) +{ + bfd_vma size; + + if (is_default_attr (attr)) + return 0; + + size = uleb128_size (tag); + if (attr->type & 1) + size += uleb128_size (attr->i); + if (attr->type & 2) + size += strlen ((char *)attr->s) + 1; + return size; +} + +/* Return the vendor name for a given object attributes section. */ +static const char * +vendor_obj_attr_name (bfd *abfd, int vendor) +{ + return (vendor == OBJ_ATTR_PROC + ? get_elf_backend_data (abfd)->obj_attrs_vendor + : "gnu"); +} + +/* Return the size of the object attributes section for VENDOR + (OBJ_ATTR_PROC or OBJ_ATTR_GNU), or 0 if there are no attributes + for that vendor to record and the vendor is OBJ_ATTR_GNU. */ +static bfd_vma +vendor_obj_attr_size (bfd *abfd, int vendor) +{ + bfd_vma size; + obj_attribute *attr; + obj_attribute_list *list; + int i; + const char *vendor_name = vendor_obj_attr_name (abfd, vendor); + + if (!vendor_name) + return 0; + + attr = elf_known_obj_attributes (abfd)[vendor]; + size = 0; + for (i = 4; i < NUM_KNOWN_OBJ_ATTRIBUTES; i++) + size += obj_attr_size (i, &attr[i]); + + for (list = elf_other_obj_attributes (abfd)[vendor]; + list; + list = list->next) + size += obj_attr_size (list->tag, &list->attr); + + /* <size> <vendor_name> NUL 0x1 <size> */ + return ((size || vendor == OBJ_ATTR_PROC) + ? size + 10 + strlen (vendor_name) + : 0); +} + +/* Return the size of the object attributes section. */ +bfd_vma +bfd_elf_obj_attr_size (bfd *abfd) +{ + bfd_vma size; + + size = vendor_obj_attr_size (abfd, OBJ_ATTR_PROC); + size += vendor_obj_attr_size (abfd, OBJ_ATTR_GNU); + + /* 'A' <sections for each vendor> */ + return (size ? size + 1 : 0); +} + +/* Write VAL in uleb128 format to P, returning a pointer to the + following byte. */ +static bfd_byte * +write_uleb128 (bfd_byte *p, unsigned int val) +{ + bfd_byte c; + do + { + c = val & 0x7f; + val >>= 7; + if (val) + c |= 0x80; + *(p++) = c; + } + while (val); + return p; +} + +/* Write attribute ATTR to butter P, and return a pointer to the following + byte. */ +static bfd_byte * +write_obj_attribute (bfd_byte *p, int tag, obj_attribute *attr) +{ + /* Suppress default entries. */ + if (is_default_attr (attr)) + return p; + + p = write_uleb128 (p, tag); + if (attr->type & 1) + p = write_uleb128 (p, attr->i); + if (attr->type & 2) + { + int len; + + len = strlen (attr->s) + 1; + memcpy (p, attr->s, len); + p += len; + } + + return p; +} + +/* Write the contents of the object attributes section (length SIZE) + for VENDOR to CONTENTS. */ +static void +vendor_set_obj_attr_contents (bfd *abfd, bfd_byte *contents, bfd_vma size, + int vendor) +{ + bfd_byte *p; + obj_attribute *attr; + obj_attribute_list *list; + int i; + const char *vendor_name = vendor_obj_attr_name (abfd, vendor); + size_t vendor_length = strlen (vendor_name) + 1; + + p = contents; + bfd_put_32 (abfd, size, p); + p += 4; + memcpy (p, vendor_name, vendor_length); + p += vendor_length; + *(p++) = Tag_File; + bfd_put_32 (abfd, size - 4 - vendor_length, p); + p += 4; + + attr = elf_known_obj_attributes (abfd)[vendor]; + for (i = 4; i < NUM_KNOWN_OBJ_ATTRIBUTES; i++) + p = write_obj_attribute (p, i, &attr[i]); + + for (list = elf_other_obj_attributes (abfd)[vendor]; + list; + list = list->next) + p = write_obj_attribute (p, list->tag, &list->attr); +} + +/* Write the contents of the object attributes section to CONTENTS. */ +void +bfd_elf_set_obj_attr_contents (bfd *abfd, bfd_byte *contents, bfd_vma size) +{ + bfd_byte *p; + int vendor; + bfd_vma my_size; + + p = contents; + *(p++) = 'A'; + my_size = 1; + for (vendor = OBJ_ATTR_FIRST; vendor <= OBJ_ATTR_LAST; vendor++) + { + bfd_vma vendor_size = vendor_obj_attr_size (abfd, vendor); + if (vendor_size) + vendor_set_obj_attr_contents (abfd, p, vendor_size, vendor); + p += vendor_size; + my_size += vendor_size; + } + + if (size != my_size) + abort (); +} + +/* Allocate/find an object attribute. */ +static obj_attribute * +elf_new_obj_attr (bfd *abfd, int vendor, int tag) +{ + obj_attribute *attr; + obj_attribute_list *list; + obj_attribute_list *p; + obj_attribute_list **lastp; + + + if (tag < NUM_KNOWN_OBJ_ATTRIBUTES) + { + /* Knwon tags are preallocated. */ + attr = &elf_known_obj_attributes (abfd)[vendor][tag]; + } + else + { + /* Create a new tag. */ + list = (obj_attribute_list *) + bfd_alloc (abfd, sizeof (obj_attribute_list)); + memset (list, 0, sizeof (obj_attribute_list)); + list->tag = tag; + /* Keep the tag list in order. */ + lastp = &elf_other_obj_attributes (abfd)[vendor]; + for (p = *lastp; p; p = p->next) + { + if (tag < p->tag) + break; + lastp = &p->next; + } + list->next = *lastp; + *lastp = list; + attr = &list->attr; + } + + return attr; +} + +/* Return the value of an integer object attribute. */ +int +bfd_elf_get_obj_attr_int (bfd *abfd, int vendor, int tag) +{ + obj_attribute_list *p; + + if (tag < NUM_KNOWN_OBJ_ATTRIBUTES) + { + /* Knwon tags are preallocated. */ + return elf_known_obj_attributes (abfd)[vendor][tag].i; + } + else + { + for (p = elf_other_obj_attributes (abfd)[vendor]; + p; + p = p->next) + { + if (tag == p->tag) + return p->attr.i; + if (tag < p->tag) + break; + } + return 0; + } +} + +/* Add an integer object attribute. */ +void +bfd_elf_add_obj_attr_int (bfd *abfd, int vendor, int tag, unsigned int i) +{ + obj_attribute *attr; + + attr = elf_new_obj_attr (abfd, vendor, tag); + attr->type = 1; + attr->i = i; +} + +/* Duplicate an object attribute string value. */ +char * +_bfd_elf_attr_strdup (bfd *abfd, const char * s) +{ + char * p; + int len; + + len = strlen (s) + 1; + p = (char *) bfd_alloc (abfd, len); + return memcpy (p, s, len); +} + +/* Add a string object attribute. */ +void +bfd_elf_add_obj_attr_string (bfd *abfd, int vendor, int tag, const char *s) +{ + obj_attribute *attr; + + attr = elf_new_obj_attr (abfd, vendor, tag); + attr->type = 2; + attr->s = _bfd_elf_attr_strdup (abfd, s); +} + +/* Add a Tag_compatibility object attribute. */ +void +bfd_elf_add_obj_attr_compat (bfd *abfd, int vendor, unsigned int i, + const char *s) +{ + obj_attribute_list *list; + obj_attribute_list *p; + obj_attribute_list **lastp; + + list = (obj_attribute_list *) + bfd_alloc (abfd, sizeof (obj_attribute_list)); + memset (list, 0, sizeof (obj_attribute_list)); + list->tag = Tag_compatibility; + list->attr.type = 3; + list->attr.i = i; + list->attr.s = _bfd_elf_attr_strdup (abfd, s); + + lastp = &elf_other_obj_attributes (abfd)[vendor]; + for (p = *lastp; p; p = p->next) + { + int cmp; + if (p->tag != Tag_compatibility) + break; + cmp = strcmp(s, p->attr.s); + if (cmp < 0 || (cmp == 0 && i < p->attr.i)) + break; + lastp = &p->next; + } + list->next = *lastp; + *lastp = list; +} + +/* Copy the object attributes from IBFD to OBFD. */ +void +_bfd_elf_copy_obj_attributes (bfd *ibfd, bfd *obfd) +{ + obj_attribute *in_attr; + obj_attribute *out_attr; + obj_attribute_list *list; + int i; + int vendor; + + for (vendor = OBJ_ATTR_FIRST; vendor <= OBJ_ATTR_LAST; vendor++) + { + in_attr = &elf_known_obj_attributes (ibfd)[vendor][4]; + out_attr = &elf_known_obj_attributes (obfd)[vendor][4]; + for (i = 4; i < NUM_KNOWN_OBJ_ATTRIBUTES; i++) + { + out_attr->type = in_attr->type; + out_attr->i = in_attr->i; + if (in_attr->s && *in_attr->s) + out_attr->s = _bfd_elf_attr_strdup (obfd, in_attr->s); + in_attr++; + out_attr++; + } + + for (list = elf_other_obj_attributes (ibfd)[vendor]; + list; + list = list->next) + { + in_attr = &list->attr; + switch (in_attr->type) + { + case 1: + bfd_elf_add_obj_attr_int (obfd, vendor, list->tag, in_attr->i); + break; + case 2: + bfd_elf_add_obj_attr_string (obfd, vendor, list->tag, + in_attr->s); + break; + case 3: + bfd_elf_add_obj_attr_compat (obfd, vendor, in_attr->i, + in_attr->s); + break; + default: + abort (); + } + } + } +} + +/* Determine whether a GNU object attribute tag takes an integer, a + string or both. */ +static int +gnu_obj_attrs_arg_type (int tag) +{ + /* Except for Tag_compatibility, for GNU attributes we follow the + same rule ARM ones > 32 follow: odd-numbered tags take strings + and even-numbered tags take integers. In addition, tag & 2 is + nonzero for architecture-independent tags and zero for + architecture-dependent ones. */ + if (tag == Tag_compatibility) + return 3; + else + return (tag & 1) != 0 ? 2 : 1; +} + +/* Determine what arguments an attribute tag takes. */ +int +_bfd_elf_obj_attrs_arg_type (bfd *abfd, int vendor, int tag) +{ + switch (vendor) + { + case OBJ_ATTR_PROC: + return get_elf_backend_data (abfd)->obj_attrs_arg_type (tag); + break; + case OBJ_ATTR_GNU: + return gnu_obj_attrs_arg_type (tag); + break; + default: + abort (); + } +} + +/* Parse an object attributes section. */ +void +_bfd_elf_parse_attributes (bfd *abfd, Elf_Internal_Shdr * hdr) +{ + bfd_byte *contents; + bfd_byte *p; + bfd_vma len; + const char *std_section; + + contents = bfd_malloc (hdr->sh_size); + if (!contents) + return; + if (!bfd_get_section_contents (abfd, hdr->bfd_section, contents, 0, + hdr->sh_size)) + { + free (contents); + return; + } + p = contents; + std_section = get_elf_backend_data (abfd)->obj_attrs_vendor; + if (*(p++) == 'A') + { + len = hdr->sh_size - 1; + while (len > 0) + { + int namelen; + bfd_vma section_len; + int vendor; + + section_len = bfd_get_32 (abfd, p); + p += 4; + if (section_len > len) + section_len = len; + len -= section_len; + namelen = strlen ((char *)p) + 1; + section_len -= namelen + 4; + if (std_section && strcmp ((char *)p, std_section) == 0) + vendor = OBJ_ATTR_PROC; + else if (strcmp ((char *)p, "gnu") == 0) + vendor = OBJ_ATTR_GNU; + else + { + /* Other vendor section. Ignore it. */ + p += namelen + section_len; + continue; + } + + p += namelen; + while (section_len > 0) + { + int tag; + unsigned int n; + unsigned int val; + bfd_vma subsection_len; + bfd_byte *end; + + tag = read_unsigned_leb128 (abfd, p, &n); + p += n; + subsection_len = bfd_get_32 (abfd, p); + p += 4; + if (subsection_len > section_len) + subsection_len = section_len; + section_len -= subsection_len; + subsection_len -= n + 4; + end = p + subsection_len; + switch (tag) + { + case Tag_File: + while (p < end) + { + int type; + + tag = read_unsigned_leb128 (abfd, p, &n); + p += n; + type = _bfd_elf_obj_attrs_arg_type (abfd, vendor, tag); + switch (type) + { + case 3: + val = read_unsigned_leb128 (abfd, p, &n); + p += n; + bfd_elf_add_obj_attr_compat (abfd, vendor, val, + (char *)p); + p += strlen ((char *)p) + 1; + break; + case 2: + bfd_elf_add_obj_attr_string (abfd, vendor, tag, + (char *)p); + p += strlen ((char *)p) + 1; + break; + case 1: + val = read_unsigned_leb128 (abfd, p, &n); + p += n; + bfd_elf_add_obj_attr_int (abfd, vendor, tag, val); + break; + default: + abort (); + } + } + break; + case Tag_Section: + case Tag_Symbol: + /* Don't have anywhere convenient to attach these. + Fall through for now. */ + default: + /* Ignore things we don't kow about. */ + p += subsection_len; + subsection_len = 0; + break; + } + } + } + } + free (contents); +} + +/* Merge common object attributes from IBFD into OBFD. Raise an error + if there are conflicting attributes. Any processor-specific + attributes have already been merged. This must be called from the + bfd_elfNN_bfd_merge_private_bfd_data hook for each individual + target, along with any target-specific merging. Because there are + no common attributes other than Tag_compatibility at present, and + non-"gnu" Tag_compatibility is not expected in "gnu" sections, this + is not presently called for targets without their own + attributes. */ + +bfd_boolean +_bfd_elf_merge_object_attributes (bfd *ibfd, bfd *obfd) +{ + obj_attribute *in_attr; + obj_attribute *out_attr; + obj_attribute_list *in_list; + obj_attribute_list *out_list; + int vendor; + + /* The only common attribute is currently Tag_compatibility, + accepted in both processor and "gnu" sections. */ + for (vendor = OBJ_ATTR_FIRST; vendor <= OBJ_ATTR_LAST; vendor++) + { + in_list = elf_other_obj_attributes (ibfd)[vendor]; + out_list = elf_other_obj_attributes (ibfd)[vendor]; + while (in_list && in_list->tag == Tag_compatibility) + { + in_attr = &in_list->attr; + if (in_attr->i == 0) + continue; + if (in_attr->i == 1 && strcmp (in_attr->s, "gnu") != 0) + { + _bfd_error_handler + (_("ERROR: %B: Must be processed by '%s' toolchain"), + ibfd, in_attr->s); + return FALSE; + } + if (!out_list || out_list->tag != Tag_compatibility + || strcmp (in_attr->s, out_list->attr.s) != 0) + { + /* Add this compatibility tag to the output. */ + bfd_elf_add_proc_attr_compat (obfd, in_attr->i, in_attr->s); + continue; + } + out_attr = &out_list->attr; + /* Check all the input tags with the same identifier. */ + for (;;) + { + if (out_list->tag != Tag_compatibility + || in_attr->i != out_attr->i + || strcmp (in_attr->s, out_attr->s) != 0) + { + _bfd_error_handler + (_("ERROR: %B: Incompatible object tag '%s':%d"), + ibfd, in_attr->s, in_attr->i); + return FALSE; + } + in_list = in_list->next; + if (in_list->tag != Tag_compatibility + || strcmp (in_attr->s, in_list->attr.s) != 0) + break; + in_attr = &in_list->attr; + out_list = out_list->next; + if (out_list) + out_attr = &out_list->attr; + } + + /* Check the output doesn't have extra tags with this identifier. */ + if (out_list && out_list->tag == Tag_compatibility + && strcmp (in_attr->s, out_list->attr.s) == 0) + { + _bfd_error_handler + (_("ERROR: %B: Incompatible object tag '%s':%d"), + ibfd, in_attr->s, out_list->attr.i); + return FALSE; + } + } + } + + return TRUE; +} |