| /* elf.c -- Get debug data from an ELF file for backtraces. |
| Copyright (C) 2012-2021 Free Software Foundation, Inc. |
| Written by Ian Lance Taylor, Google. |
| |
| 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. |
| |
| (3) The name of the author may not be used to |
| endorse or promote products derived from this software without |
| specific prior written permission. |
| |
| 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. */ |
| |
| #include "config.h" |
| |
| #include <errno.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <unistd.h> |
| |
| #ifdef HAVE_DL_ITERATE_PHDR |
| #include <link.h> |
| #endif |
| |
| #include "backtrace.h" |
| #include "internal.h" |
| |
| #ifndef S_ISLNK |
| #ifndef S_IFLNK |
| #define S_IFLNK 0120000 |
| #endif |
| #ifndef S_IFMT |
| #define S_IFMT 0170000 |
| #endif |
| #define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK) |
| #endif |
| |
| #ifndef __GNUC__ |
| #define __builtin_prefetch(p, r, l) |
| #define unlikely(x) (x) |
| #else |
| #define unlikely(x) __builtin_expect(!!(x), 0) |
| #endif |
| |
| #if !defined(HAVE_DECL_STRNLEN) || !HAVE_DECL_STRNLEN |
| |
| /* If strnlen is not declared, provide our own version. */ |
| |
| static size_t |
| xstrnlen (const char *s, size_t maxlen) |
| { |
| size_t i; |
| |
| for (i = 0; i < maxlen; ++i) |
| if (s[i] == '\0') |
| break; |
| return i; |
| } |
| |
| #define strnlen xstrnlen |
| |
| #endif |
| |
| #ifndef HAVE_LSTAT |
| |
| /* Dummy version of lstat for systems that don't have it. */ |
| |
| static int |
| xlstat (const char *path ATTRIBUTE_UNUSED, struct stat *st ATTRIBUTE_UNUSED) |
| { |
| return -1; |
| } |
| |
| #define lstat xlstat |
| |
| #endif |
| |
| #ifndef HAVE_READLINK |
| |
| /* Dummy version of readlink for systems that don't have it. */ |
| |
| static ssize_t |
| xreadlink (const char *path ATTRIBUTE_UNUSED, char *buf ATTRIBUTE_UNUSED, |
| size_t bufsz ATTRIBUTE_UNUSED) |
| { |
| return -1; |
| } |
| |
| #define readlink xreadlink |
| |
| #endif |
| |
| #ifndef HAVE_DL_ITERATE_PHDR |
| |
| /* Dummy version of dl_iterate_phdr for systems that don't have it. */ |
| |
| #define dl_phdr_info x_dl_phdr_info |
| #define dl_iterate_phdr x_dl_iterate_phdr |
| |
| struct dl_phdr_info |
| { |
| uintptr_t dlpi_addr; |
| const char *dlpi_name; |
| }; |
| |
| static int |
| dl_iterate_phdr (int (*callback) (struct dl_phdr_info *, |
| size_t, void *) ATTRIBUTE_UNUSED, |
| void *data ATTRIBUTE_UNUSED) |
| { |
| return 0; |
| } |
| |
| #endif /* ! defined (HAVE_DL_ITERATE_PHDR) */ |
| |
| /* The configure script must tell us whether we are 32-bit or 64-bit |
| ELF. We could make this code test and support either possibility, |
| but there is no point. This code only works for the currently |
| running executable, which means that we know the ELF mode at |
| configure time. */ |
| |
| #if BACKTRACE_ELF_SIZE != 32 && BACKTRACE_ELF_SIZE != 64 |
| #error "Unknown BACKTRACE_ELF_SIZE" |
| #endif |
| |
| /* <link.h> might #include <elf.h> which might define our constants |
| with slightly different values. Undefine them to be safe. */ |
| |
| #undef EI_NIDENT |
| #undef EI_MAG0 |
| #undef EI_MAG1 |
| #undef EI_MAG2 |
| #undef EI_MAG3 |
| #undef EI_CLASS |
| #undef EI_DATA |
| #undef EI_VERSION |
| #undef ELF_MAG0 |
| #undef ELF_MAG1 |
| #undef ELF_MAG2 |
| #undef ELF_MAG3 |
| #undef ELFCLASS32 |
| #undef ELFCLASS64 |
| #undef ELFDATA2LSB |
| #undef ELFDATA2MSB |
| #undef EV_CURRENT |
| #undef ET_DYN |
| #undef EM_PPC64 |
| #undef EF_PPC64_ABI |
| #undef SHN_LORESERVE |
| #undef SHN_XINDEX |
| #undef SHN_UNDEF |
| #undef SHT_PROGBITS |
| #undef SHT_SYMTAB |
| #undef SHT_STRTAB |
| #undef SHT_DYNSYM |
| #undef SHF_COMPRESSED |
| #undef STT_OBJECT |
| #undef STT_FUNC |
| #undef NT_GNU_BUILD_ID |
| #undef ELFCOMPRESS_ZLIB |
| |
| /* Basic types. */ |
| |
| typedef uint16_t b_elf_half; /* Elf_Half. */ |
| typedef uint32_t b_elf_word; /* Elf_Word. */ |
| typedef int32_t b_elf_sword; /* Elf_Sword. */ |
| |
| #if BACKTRACE_ELF_SIZE == 32 |
| |
| typedef uint32_t b_elf_addr; /* Elf_Addr. */ |
| typedef uint32_t b_elf_off; /* Elf_Off. */ |
| |
| typedef uint32_t b_elf_wxword; /* 32-bit Elf_Word, 64-bit ELF_Xword. */ |
| |
| #else |
| |
| typedef uint64_t b_elf_addr; /* Elf_Addr. */ |
| typedef uint64_t b_elf_off; /* Elf_Off. */ |
| typedef uint64_t b_elf_xword; /* Elf_Xword. */ |
| typedef int64_t b_elf_sxword; /* Elf_Sxword. */ |
| |
| typedef uint64_t b_elf_wxword; /* 32-bit Elf_Word, 64-bit ELF_Xword. */ |
| |
| #endif |
| |
| /* Data structures and associated constants. */ |
| |
| #define EI_NIDENT 16 |
| |
| typedef struct { |
| unsigned char e_ident[EI_NIDENT]; /* ELF "magic number" */ |
| b_elf_half e_type; /* Identifies object file type */ |
| b_elf_half e_machine; /* Specifies required architecture */ |
| b_elf_word e_version; /* Identifies object file version */ |
| b_elf_addr e_entry; /* Entry point virtual address */ |
| b_elf_off e_phoff; /* Program header table file offset */ |
| b_elf_off e_shoff; /* Section header table file offset */ |
| b_elf_word e_flags; /* Processor-specific flags */ |
| b_elf_half e_ehsize; /* ELF header size in bytes */ |
| b_elf_half e_phentsize; /* Program header table entry size */ |
| b_elf_half e_phnum; /* Program header table entry count */ |
| b_elf_half e_shentsize; /* Section header table entry size */ |
| b_elf_half e_shnum; /* Section header table entry count */ |
| b_elf_half e_shstrndx; /* Section header string table index */ |
| } b_elf_ehdr; /* Elf_Ehdr. */ |
| |
| #define EI_MAG0 0 |
| #define EI_MAG1 1 |
| #define EI_MAG2 2 |
| #define EI_MAG3 3 |
| #define EI_CLASS 4 |
| #define EI_DATA 5 |
| #define EI_VERSION 6 |
| |
| #define ELFMAG0 0x7f |
| #define ELFMAG1 'E' |
| #define ELFMAG2 'L' |
| #define ELFMAG3 'F' |
| |
| #define ELFCLASS32 1 |
| #define ELFCLASS64 2 |
| |
| #define ELFDATA2LSB 1 |
| #define ELFDATA2MSB 2 |
| |
| #define EV_CURRENT 1 |
| |
| #define ET_DYN 3 |
| |
| #define EM_PPC64 21 |
| #define EF_PPC64_ABI 3 |
| |
| typedef struct { |
| b_elf_word sh_name; /* Section name, index in string tbl */ |
| b_elf_word sh_type; /* Type of section */ |
| b_elf_wxword sh_flags; /* Miscellaneous section attributes */ |
| b_elf_addr sh_addr; /* Section virtual addr at execution */ |
| b_elf_off sh_offset; /* Section file offset */ |
| b_elf_wxword sh_size; /* Size of section in bytes */ |
| b_elf_word sh_link; /* Index of another section */ |
| b_elf_word sh_info; /* Additional section information */ |
| b_elf_wxword sh_addralign; /* Section alignment */ |
| b_elf_wxword sh_entsize; /* Entry size if section holds table */ |
| } b_elf_shdr; /* Elf_Shdr. */ |
| |
| #define SHN_UNDEF 0x0000 /* Undefined section */ |
| #define SHN_LORESERVE 0xFF00 /* Begin range of reserved indices */ |
| #define SHN_XINDEX 0xFFFF /* Section index is held elsewhere */ |
| |
| #define SHT_PROGBITS 1 |
| #define SHT_SYMTAB 2 |
| #define SHT_STRTAB 3 |
| #define SHT_DYNSYM 11 |
| |
| #define SHF_COMPRESSED 0x800 |
| |
| #if BACKTRACE_ELF_SIZE == 32 |
| |
| typedef struct |
| { |
| b_elf_word st_name; /* Symbol name, index in string tbl */ |
| b_elf_addr st_value; /* Symbol value */ |
| b_elf_word st_size; /* Symbol size */ |
| unsigned char st_info; /* Symbol binding and type */ |
| unsigned char st_other; /* Visibility and other data */ |
| b_elf_half st_shndx; /* Symbol section index */ |
| } b_elf_sym; /* Elf_Sym. */ |
| |
| #else /* BACKTRACE_ELF_SIZE != 32 */ |
| |
| typedef struct |
| { |
| b_elf_word st_name; /* Symbol name, index in string tbl */ |
| unsigned char st_info; /* Symbol binding and type */ |
| unsigned char st_other; /* Visibility and other data */ |
| b_elf_half st_shndx; /* Symbol section index */ |
| b_elf_addr st_value; /* Symbol value */ |
| b_elf_xword st_size; /* Symbol size */ |
| } b_elf_sym; /* Elf_Sym. */ |
| |
| #endif /* BACKTRACE_ELF_SIZE != 32 */ |
| |
| #define STT_OBJECT 1 |
| #define STT_FUNC 2 |
| |
| typedef struct |
| { |
| uint32_t namesz; |
| uint32_t descsz; |
| uint32_t type; |
| char name[1]; |
| } b_elf_note; |
| |
| #define NT_GNU_BUILD_ID 3 |
| |
| #if BACKTRACE_ELF_SIZE == 32 |
| |
| typedef struct |
| { |
| b_elf_word ch_type; /* Compresstion algorithm */ |
| b_elf_word ch_size; /* Uncompressed size */ |
| b_elf_word ch_addralign; /* Alignment for uncompressed data */ |
| } b_elf_chdr; /* Elf_Chdr */ |
| |
| #else /* BACKTRACE_ELF_SIZE != 32 */ |
| |
| typedef struct |
| { |
| b_elf_word ch_type; /* Compression algorithm */ |
| b_elf_word ch_reserved; /* Reserved */ |
| b_elf_xword ch_size; /* Uncompressed size */ |
| b_elf_xword ch_addralign; /* Alignment for uncompressed data */ |
| } b_elf_chdr; /* Elf_Chdr */ |
| |
| #endif /* BACKTRACE_ELF_SIZE != 32 */ |
| |
| #define ELFCOMPRESS_ZLIB 1 |
| |
| /* Names of sections, indexed by enum dwarf_section in internal.h. */ |
| |
| static const char * const dwarf_section_names[DEBUG_MAX] = |
| { |
| ".debug_info", |
| ".debug_line", |
| ".debug_abbrev", |
| ".debug_ranges", |
| ".debug_str", |
| ".debug_addr", |
| ".debug_str_offsets", |
| ".debug_line_str", |
| ".debug_rnglists" |
| }; |
| |
| /* Information we gather for the sections we care about. */ |
| |
| struct debug_section_info |
| { |
| /* Section file offset. */ |
| off_t offset; |
| /* Section size. */ |
| size_t size; |
| /* Section contents, after read from file. */ |
| const unsigned char *data; |
| /* Whether the SHF_COMPRESSED flag is set for the section. */ |
| int compressed; |
| }; |
| |
| /* Information we keep for an ELF symbol. */ |
| |
| struct elf_symbol |
| { |
| /* The name of the symbol. */ |
| const char *name; |
| /* The address of the symbol. */ |
| uintptr_t address; |
| /* The size of the symbol. */ |
| size_t size; |
| }; |
| |
| /* Information to pass to elf_syminfo. */ |
| |
| struct elf_syminfo_data |
| { |
| /* Symbols for the next module. */ |
| struct elf_syminfo_data *next; |
| /* The ELF symbols, sorted by address. */ |
| struct elf_symbol *symbols; |
| /* The number of symbols. */ |
| size_t count; |
| }; |
| |
| /* A view that works for either a file or memory. */ |
| |
| struct elf_view |
| { |
| struct backtrace_view view; |
| int release; /* If non-zero, must call backtrace_release_view. */ |
| }; |
| |
| /* Information about PowerPC64 ELFv1 .opd section. */ |
| |
| struct elf_ppc64_opd_data |
| { |
| /* Address of the .opd section. */ |
| b_elf_addr addr; |
| /* Section data. */ |
| const char *data; |
| /* Size of the .opd section. */ |
| size_t size; |
| /* Corresponding section view. */ |
| struct elf_view view; |
| }; |
| |
| /* Create a view of SIZE bytes from DESCRIPTOR/MEMORY at OFFSET. */ |
| |
| static int |
| elf_get_view (struct backtrace_state *state, int descriptor, |
| const unsigned char *memory, size_t memory_size, off_t offset, |
| uint64_t size, backtrace_error_callback error_callback, |
| void *data, struct elf_view *view) |
| { |
| if (memory == NULL) |
| { |
| view->release = 1; |
| return backtrace_get_view (state, descriptor, offset, size, |
| error_callback, data, &view->view); |
| } |
| else |
| { |
| if ((uint64_t) offset + size > (uint64_t) memory_size) |
| { |
| error_callback (data, "out of range for in-memory file", 0); |
| return 0; |
| } |
| view->view.data = (const void *) (memory + offset); |
| view->view.base = NULL; |
| view->view.len = size; |
| view->release = 0; |
| return 1; |
| } |
| } |
| |
| /* Release a view read by elf_get_view. */ |
| |
| static void |
| elf_release_view (struct backtrace_state *state, struct elf_view *view, |
| backtrace_error_callback error_callback, void *data) |
| { |
| if (view->release) |
| backtrace_release_view (state, &view->view, error_callback, data); |
| } |
| |
| /* Compute the CRC-32 of BUF/LEN. This uses the CRC used for |
| .gnu_debuglink files. */ |
| |
| static uint32_t |
| elf_crc32 (uint32_t crc, const unsigned char *buf, size_t len) |
| { |
| static const uint32_t crc32_table[256] = |
| { |
| 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, |
| 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, |
| 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, |
| 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, |
| 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, |
| 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, |
| 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, |
| 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, |
| 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, |
| 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, |
| 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, |
| 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, |
| 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, |
| 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, |
| 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, |
| 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, |
| 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, |
| 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, |
| 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, |
| 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, |
| 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, |
| 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, |
| 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, |
| 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, |
| 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, |
| 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, |
| 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, |
| 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, |
| 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, |
| 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, |
| 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, |
| 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, |
| 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, |
| 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, |
| 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, |
| 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, |
| 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, |
| 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, |
| 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, |
| 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, |
| 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, |
| 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, |
| 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, |
| 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, |
| 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, |
| 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, |
| 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, |
| 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, |
| 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, |
| 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, |
| 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, |
| 0x2d02ef8d |
| }; |
| const unsigned char *end; |
| |
| crc = ~crc; |
| for (end = buf + len; buf < end; ++ buf) |
| crc = crc32_table[(crc ^ *buf) & 0xff] ^ (crc >> 8); |
| return ~crc; |
| } |
| |
| /* Return the CRC-32 of the entire file open at DESCRIPTOR. */ |
| |
| static uint32_t |
| elf_crc32_file (struct backtrace_state *state, int descriptor, |
| backtrace_error_callback error_callback, void *data) |
| { |
| struct stat st; |
| struct backtrace_view file_view; |
| uint32_t ret; |
| |
| if (fstat (descriptor, &st) < 0) |
| { |
| error_callback (data, "fstat", errno); |
| return 0; |
| } |
| |
| if (!backtrace_get_view (state, descriptor, 0, st.st_size, error_callback, |
| data, &file_view)) |
| return 0; |
| |
| ret = elf_crc32 (0, (const unsigned char *) file_view.data, st.st_size); |
| |
| backtrace_release_view (state, &file_view, error_callback, data); |
| |
| return ret; |
| } |
| |
| /* A dummy callback function used when we can't find a symbol |
| table. */ |
| |
| static void |
| elf_nosyms (struct backtrace_state *state ATTRIBUTE_UNUSED, |
| uintptr_t addr ATTRIBUTE_UNUSED, |
| backtrace_syminfo_callback callback ATTRIBUTE_UNUSED, |
| backtrace_error_callback error_callback, void *data) |
| { |
| error_callback (data, "no symbol table in ELF executable", -1); |
| } |
| |
| /* A callback function used when we can't find any debug info. */ |
| |
| static int |
| elf_nodebug (struct backtrace_state *state, uintptr_t pc, |
| backtrace_full_callback callback, |
| backtrace_error_callback error_callback, void *data) |
| { |
| if (state->syminfo_fn != NULL && state->syminfo_fn != elf_nosyms) |
| { |
| struct backtrace_call_full bdata; |
| |
| /* Fetch symbol information so that we can least get the |
| function name. */ |
| |
| bdata.full_callback = callback; |
| bdata.full_error_callback = error_callback; |
| bdata.full_data = data; |
| bdata.ret = 0; |
| state->syminfo_fn (state, pc, backtrace_syminfo_to_full_callback, |
| backtrace_syminfo_to_full_error_callback, &bdata); |
| return bdata.ret; |
| } |
| |
| error_callback (data, "no debug info in ELF executable", -1); |
| return 0; |
| } |
| |
| /* Compare struct elf_symbol for qsort. */ |
| |
| static int |
| elf_symbol_compare (const void *v1, const void *v2) |
| { |
| const struct elf_symbol *e1 = (const struct elf_symbol *) v1; |
| const struct elf_symbol *e2 = (const struct elf_symbol *) v2; |
| |
| if (e1->address < e2->address) |
| return -1; |
| else if (e1->address > e2->address) |
| return 1; |
| else |
| return 0; |
| } |
| |
| /* Compare an ADDR against an elf_symbol for bsearch. We allocate one |
| extra entry in the array so that this can look safely at the next |
| entry. */ |
| |
| static int |
| elf_symbol_search (const void *vkey, const void *ventry) |
| { |
| const uintptr_t *key = (const uintptr_t *) vkey; |
| const struct elf_symbol *entry = (const struct elf_symbol *) ventry; |
| uintptr_t addr; |
| |
| addr = *key; |
| if (addr < entry->address) |
| return -1; |
| else if (addr >= entry->address + entry->size) |
| return 1; |
| else |
| return 0; |
| } |
| |
| /* Initialize the symbol table info for elf_syminfo. */ |
| |
| static int |
| elf_initialize_syminfo (struct backtrace_state *state, |
| uintptr_t base_address, |
| const unsigned char *symtab_data, size_t symtab_size, |
| const unsigned char *strtab, size_t strtab_size, |
| backtrace_error_callback error_callback, |
| void *data, struct elf_syminfo_data *sdata, |
| struct elf_ppc64_opd_data *opd) |
| { |
| size_t sym_count; |
| const b_elf_sym *sym; |
| size_t elf_symbol_count; |
| size_t elf_symbol_size; |
| struct elf_symbol *elf_symbols; |
| size_t i; |
| unsigned int j; |
| |
| sym_count = symtab_size / sizeof (b_elf_sym); |
| |
| /* We only care about function symbols. Count them. */ |
| sym = (const b_elf_sym *) symtab_data; |
| elf_symbol_count = 0; |
| for (i = 0; i < sym_count; ++i, ++sym) |
| { |
| int info; |
| |
| info = sym->st_info & 0xf; |
| if ((info == STT_FUNC || info == STT_OBJECT) |
| && sym->st_shndx != SHN_UNDEF) |
| ++elf_symbol_count; |
| } |
| |
| elf_symbol_size = elf_symbol_count * sizeof (struct elf_symbol); |
| elf_symbols = ((struct elf_symbol *) |
| backtrace_alloc (state, elf_symbol_size, error_callback, |
| data)); |
| if (elf_symbols == NULL) |
| return 0; |
| |
| sym = (const b_elf_sym *) symtab_data; |
| j = 0; |
| for (i = 0; i < sym_count; ++i, ++sym) |
| { |
| int info; |
| |
| info = sym->st_info & 0xf; |
| if (info != STT_FUNC && info != STT_OBJECT) |
| continue; |
| if (sym->st_shndx == SHN_UNDEF) |
| continue; |
| if (sym->st_name >= strtab_size) |
| { |
| error_callback (data, "symbol string index out of range", 0); |
| backtrace_free (state, elf_symbols, elf_symbol_size, error_callback, |
| data); |
| return 0; |
| } |
| elf_symbols[j].name = (const char *) strtab + sym->st_name; |
| /* Special case PowerPC64 ELFv1 symbols in .opd section, if the symbol |
| is a function descriptor, read the actual code address from the |
| descriptor. */ |
| if (opd |
| && sym->st_value >= opd->addr |
| && sym->st_value < opd->addr + opd->size) |
| elf_symbols[j].address |
| = *(const b_elf_addr *) (opd->data + (sym->st_value - opd->addr)); |
| else |
| elf_symbols[j].address = sym->st_value; |
| elf_symbols[j].address += base_address; |
| elf_symbols[j].size = sym->st_size; |
| ++j; |
| } |
| |
| backtrace_qsort (elf_symbols, elf_symbol_count, sizeof (struct elf_symbol), |
| elf_symbol_compare); |
| |
| sdata->next = NULL; |
| sdata->symbols = elf_symbols; |
| sdata->count = elf_symbol_count; |
| |
| return 1; |
| } |
| |
| /* Add EDATA to the list in STATE. */ |
| |
| static void |
| elf_add_syminfo_data (struct backtrace_state *state, |
| struct elf_syminfo_data *edata) |
| { |
| if (!state->threaded) |
| { |
| struct elf_syminfo_data **pp; |
| |
| for (pp = (struct elf_syminfo_data **) (void *) &state->syminfo_data; |
| *pp != NULL; |
| pp = &(*pp)->next) |
| ; |
| *pp = edata; |
| } |
| else |
| { |
| while (1) |
| { |
| struct elf_syminfo_data **pp; |
| |
| pp = (struct elf_syminfo_data **) (void *) &state->syminfo_data; |
| |
| while (1) |
| { |
| struct elf_syminfo_data *p; |
| |
| p = backtrace_atomic_load_pointer (pp); |
| |
| if (p == NULL) |
| break; |
| |
| pp = &p->next; |
| } |
| |
| if (__sync_bool_compare_and_swap (pp, NULL, edata)) |
| break; |
| } |
| } |
| } |
| |
| /* Return the symbol name and value for an ADDR. */ |
| |
| static void |
| elf_syminfo (struct backtrace_state *state, uintptr_t addr, |
| backtrace_syminfo_callback callback, |
| backtrace_error_callback error_callback ATTRIBUTE_UNUSED, |
| void *data) |
| { |
| struct elf_syminfo_data *edata; |
| struct elf_symbol *sym = NULL; |
| |
| if (!state->threaded) |
| { |
| for (edata = (struct elf_syminfo_data *) state->syminfo_data; |
| edata != NULL; |
| edata = edata->next) |
| { |
| sym = ((struct elf_symbol *) |
| bsearch (&addr, edata->symbols, edata->count, |
| sizeof (struct elf_symbol), elf_symbol_search)); |
| if (sym != NULL) |
| break; |
| } |
| } |
| else |
| { |
| struct elf_syminfo_data **pp; |
| |
| pp = (struct elf_syminfo_data **) (void *) &state->syminfo_data; |
| while (1) |
| { |
| edata = backtrace_atomic_load_pointer (pp); |
| if (edata == NULL) |
| break; |
| |
| sym = ((struct elf_symbol *) |
| bsearch (&addr, edata->symbols, edata->count, |
| sizeof (struct elf_symbol), elf_symbol_search)); |
| if (sym != NULL) |
| break; |
| |
| pp = &edata->next; |
| } |
| } |
| |
| if (sym == NULL) |
| callback (data, addr, NULL, 0, 0); |
| else |
| callback (data, addr, sym->name, sym->address, sym->size); |
| } |
| |
| /* Return whether FILENAME is a symlink. */ |
| |
| static int |
| elf_is_symlink (const char *filename) |
| { |
| struct stat st; |
| |
| if (lstat (filename, &st) < 0) |
| return 0; |
| return S_ISLNK (st.st_mode); |
| } |
| |
| /* Return the results of reading the symlink FILENAME in a buffer |
| allocated by backtrace_alloc. Return the length of the buffer in |
| *LEN. */ |
| |
| static char * |
| elf_readlink (struct backtrace_state *state, const char *filename, |
| backtrace_error_callback error_callback, void *data, |
| size_t *plen) |
| { |
| size_t len; |
| char *buf; |
| |
| len = 128; |
| while (1) |
| { |
| ssize_t rl; |
| |
| buf = backtrace_alloc (state, len, error_callback, data); |
| if (buf == NULL) |
| return NULL; |
| rl = readlink (filename, buf, len); |
| if (rl < 0) |
| { |
| backtrace_free (state, buf, len, error_callback, data); |
| return NULL; |
| } |
| if ((size_t) rl < len - 1) |
| { |
| buf[rl] = '\0'; |
| *plen = len; |
| return buf; |
| } |
| backtrace_free (state, buf, len, error_callback, data); |
| len *= 2; |
| } |
| } |
| |
| #define SYSTEM_BUILD_ID_DIR "/usr/lib/debug/.build-id/" |
| |
| /* Open a separate debug info file, using the build ID to find it. |
| Returns an open file descriptor, or -1. |
| |
| The GDB manual says that the only place gdb looks for a debug file |
| when the build ID is known is in /usr/lib/debug/.build-id. */ |
| |
| static int |
| elf_open_debugfile_by_buildid (struct backtrace_state *state, |
| const char *buildid_data, size_t buildid_size, |
| backtrace_error_callback error_callback, |
| void *data) |
| { |
| const char * const prefix = SYSTEM_BUILD_ID_DIR; |
| const size_t prefix_len = strlen (prefix); |
| const char * const suffix = ".debug"; |
| const size_t suffix_len = strlen (suffix); |
| size_t len; |
| char *bd_filename; |
| char *t; |
| size_t i; |
| int ret; |
| int does_not_exist; |
| |
| len = prefix_len + buildid_size * 2 + suffix_len + 2; |
| bd_filename = backtrace_alloc (state, len, error_callback, data); |
| if (bd_filename == NULL) |
| return -1; |
| |
| t = bd_filename; |
| memcpy (t, prefix, prefix_len); |
| t += prefix_len; |
| for (i = 0; i < buildid_size; i++) |
| { |
| unsigned char b; |
| unsigned char nib; |
| |
| b = (unsigned char) buildid_data[i]; |
| nib = (b & 0xf0) >> 4; |
| *t++ = nib < 10 ? '0' + nib : 'a' + nib - 10; |
| nib = b & 0x0f; |
| *t++ = nib < 10 ? '0' + nib : 'a' + nib - 10; |
| if (i == 0) |
| *t++ = '/'; |
| } |
| memcpy (t, suffix, suffix_len); |
| t[suffix_len] = '\0'; |
| |
| ret = backtrace_open (bd_filename, error_callback, data, &does_not_exist); |
| |
| backtrace_free (state, bd_filename, len, error_callback, data); |
| |
| /* gdb checks that the debuginfo file has the same build ID note. |
| That seems kind of pointless to me--why would it have the right |
| name but not the right build ID?--so skipping the check. */ |
| |
| return ret; |
| } |
| |
| /* Try to open a file whose name is PREFIX (length PREFIX_LEN) |
| concatenated with PREFIX2 (length PREFIX2_LEN) concatenated with |
| DEBUGLINK_NAME. Returns an open file descriptor, or -1. */ |
| |
| static int |
| elf_try_debugfile (struct backtrace_state *state, const char *prefix, |
| size_t prefix_len, const char *prefix2, size_t prefix2_len, |
| const char *debuglink_name, |
| backtrace_error_callback error_callback, void *data) |
| { |
| size_t debuglink_len; |
| size_t try_len; |
| char *try; |
| int does_not_exist; |
| int ret; |
| |
| debuglink_len = strlen (debuglink_name); |
| try_len = prefix_len + prefix2_len + debuglink_len + 1; |
| try = backtrace_alloc (state, try_len, error_callback, data); |
| if (try == NULL) |
| return -1; |
| |
| memcpy (try, prefix, prefix_len); |
| memcpy (try + prefix_len, prefix2, prefix2_len); |
| memcpy (try + prefix_len + prefix2_len, debuglink_name, debuglink_len); |
| try[prefix_len + prefix2_len + debuglink_len] = '\0'; |
| |
| ret = backtrace_open (try, error_callback, data, &does_not_exist); |
| |
| backtrace_free (state, try, try_len, error_callback, data); |
| |
| return ret; |
| } |
| |
| /* Find a separate debug info file, using the debuglink section data |
| to find it. Returns an open file descriptor, or -1. */ |
| |
| static int |
| elf_find_debugfile_by_debuglink (struct backtrace_state *state, |
| const char *filename, |
| const char *debuglink_name, |
| backtrace_error_callback error_callback, |
| void *data) |
| { |
| int ret; |
| char *alc; |
| size_t alc_len; |
| const char *slash; |
| int ddescriptor; |
| const char *prefix; |
| size_t prefix_len; |
| |
| /* Resolve symlinks in FILENAME. Since FILENAME is fairly likely to |
| be /proc/self/exe, symlinks are common. We don't try to resolve |
| the whole path name, just the base name. */ |
| ret = -1; |
| alc = NULL; |
| alc_len = 0; |
| while (elf_is_symlink (filename)) |
| { |
| char *new_buf; |
| size_t new_len; |
| |
| new_buf = elf_readlink (state, filename, error_callback, data, &new_len); |
| if (new_buf == NULL) |
| break; |
| |
| if (new_buf[0] == '/') |
| filename = new_buf; |
| else |
| { |
| slash = strrchr (filename, '/'); |
| if (slash == NULL) |
| filename = new_buf; |
| else |
| { |
| size_t clen; |
| char *c; |
| |
| slash++; |
| clen = slash - filename + strlen (new_buf) + 1; |
| c = backtrace_alloc (state, clen, error_callback, data); |
| if (c == NULL) |
| goto done; |
| |
| memcpy (c, filename, slash - filename); |
| memcpy (c + (slash - filename), new_buf, strlen (new_buf)); |
| c[slash - filename + strlen (new_buf)] = '\0'; |
| backtrace_free (state, new_buf, new_len, error_callback, data); |
| filename = c; |
| new_buf = c; |
| new_len = clen; |
| } |
| } |
| |
| if (alc != NULL) |
| backtrace_free (state, alc, alc_len, error_callback, data); |
| alc = new_buf; |
| alc_len = new_len; |
| } |
| |
| /* Look for DEBUGLINK_NAME in the same directory as FILENAME. */ |
| |
| slash = strrchr (filename, '/'); |
| if (slash == NULL) |
| { |
| prefix = ""; |
| prefix_len = 0; |
| } |
| else |
| { |
| slash++; |
| prefix = filename; |
| prefix_len = slash - filename; |
| } |
| |
| ddescriptor = elf_try_debugfile (state, prefix, prefix_len, "", 0, |
| debuglink_name, error_callback, data); |
| if (ddescriptor >= 0) |
| { |
| ret = ddescriptor; |
| goto done; |
| } |
| |
| /* Look for DEBUGLINK_NAME in a .debug subdirectory of FILENAME. */ |
| |
| ddescriptor = elf_try_debugfile (state, prefix, prefix_len, ".debug/", |
| strlen (".debug/"), debuglink_name, |
| error_callback, data); |
| if (ddescriptor >= 0) |
| { |
| ret = ddescriptor; |
| goto done; |
| } |
| |
| /* Look for DEBUGLINK_NAME in /usr/lib/debug. */ |
| |
| ddescriptor = elf_try_debugfile (state, "/usr/lib/debug/", |
| strlen ("/usr/lib/debug/"), prefix, |
| prefix_len, debuglink_name, |
| error_callback, data); |
| if (ddescriptor >= 0) |
| ret = ddescriptor; |
| |
| done: |
| if (alc != NULL && alc_len > 0) |
| backtrace_free (state, alc, alc_len, error_callback, data); |
| return ret; |
| } |
| |
| /* Open a separate debug info file, using the debuglink section data |
| to find it. Returns an open file descriptor, or -1. */ |
| |
| static int |
| elf_open_debugfile_by_debuglink (struct backtrace_state *state, |
| const char *filename, |
| const char *debuglink_name, |
| uint32_t debuglink_crc, |
| backtrace_error_callback error_callback, |
| void *data) |
| { |
| int ddescriptor; |
| |
| ddescriptor = elf_find_debugfile_by_debuglink (state, filename, |
| debuglink_name, |
| error_callback, data); |
| if (ddescriptor < 0) |
| return -1; |
| |
| if (debuglink_crc != 0) |
| { |
| uint32_t got_crc; |
| |
| got_crc = elf_crc32_file (state, ddescriptor, error_callback, data); |
| if (got_crc != debuglink_crc) |
| { |
| backtrace_close (ddescriptor, error_callback, data); |
| return -1; |
| } |
| } |
| |
| return ddescriptor; |
| } |
| |
| /* A function useful for setting a breakpoint for an inflation failure |
| when this code is compiled with -g. */ |
| |
| static void |
| elf_uncompress_failed(void) |
| { |
| } |
| |
| /* *PVAL is the current value being read from the stream, and *PBITS |
| is the number of valid bits. Ensure that *PVAL holds at least 15 |
| bits by reading additional bits from *PPIN, up to PINEND, as |
| needed. Updates *PPIN, *PVAL and *PBITS. Returns 1 on success, 0 |
| on error. */ |
| |
| static int |
| elf_zlib_fetch (const unsigned char **ppin, const unsigned char *pinend, |
| uint64_t *pval, unsigned int *pbits) |
| { |
| unsigned int bits; |
| const unsigned char *pin; |
| uint64_t val; |
| uint32_t next; |
| |
| bits = *pbits; |
| if (bits >= 15) |
| return 1; |
| pin = *ppin; |
| val = *pval; |
| |
| if (unlikely (pinend - pin < 4)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| #if defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) \ |
| && defined(__ORDER_BIG_ENDIAN__) \ |
| && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ \ |
| || __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) |
| /* We've ensured that PIN is aligned. */ |
| next = *(const uint32_t *)pin; |
| |
| #if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ |
| next = __builtin_bswap32 (next); |
| #endif |
| #else |
| next = pin[0] | (pin[1] << 8) | (pin[2] << 16) | (pin[3] << 24); |
| #endif |
| |
| val |= (uint64_t)next << bits; |
| bits += 32; |
| pin += 4; |
| |
| /* We will need the next four bytes soon. */ |
| __builtin_prefetch (pin, 0, 0); |
| |
| *ppin = pin; |
| *pval = val; |
| *pbits = bits; |
| return 1; |
| } |
| |
| /* Huffman code tables, like the rest of the zlib format, are defined |
| by RFC 1951. We store a Huffman code table as a series of tables |
| stored sequentially in memory. Each entry in a table is 16 bits. |
| The first, main, table has 256 entries. It is followed by a set of |
| secondary tables of length 2 to 128 entries. The maximum length of |
| a code sequence in the deflate format is 15 bits, so that is all we |
| need. Each secondary table has an index, which is the offset of |
| the table in the overall memory storage. |
| |
| The deflate format says that all codes of a given bit length are |
| lexicographically consecutive. Perhaps we could have 130 values |
| that require a 15-bit code, perhaps requiring three secondary |
| tables of size 128. I don't know if this is actually possible, but |
| it suggests that the maximum size required for secondary tables is |
| 3 * 128 + 3 * 64 ... == 768. The zlib enough program reports 660 |
| as the maximum. We permit 768, since in addition to the 256 for |
| the primary table, with two bytes per entry, and with the two |
| tables we need, that gives us a page. |
| |
| A single table entry needs to store a value or (for the main table |
| only) the index and size of a secondary table. Values range from 0 |
| to 285, inclusive. Secondary table indexes, per above, range from |
| 0 to 510. For a value we need to store the number of bits we need |
| to determine that value (one value may appear multiple times in the |
| table), which is 1 to 8. For a secondary table we need to store |
| the number of bits used to index into the table, which is 1 to 7. |
| And of course we need 1 bit to decide whether we have a value or a |
| secondary table index. So each entry needs 9 bits for value/table |
| index, 3 bits for size, 1 bit what it is. For simplicity we use 16 |
| bits per entry. */ |
| |
| /* Number of entries we allocate to for one code table. We get a page |
| for the two code tables we need. */ |
| |
| #define HUFFMAN_TABLE_SIZE (1024) |
| |
| /* Bit masks and shifts for the values in the table. */ |
| |
| #define HUFFMAN_VALUE_MASK 0x01ff |
| #define HUFFMAN_BITS_SHIFT 9 |
| #define HUFFMAN_BITS_MASK 0x7 |
| #define HUFFMAN_SECONDARY_SHIFT 12 |
| |
| /* For working memory while inflating we need two code tables, we need |
| an array of code lengths (max value 15, so we use unsigned char), |
| and an array of unsigned shorts used while building a table. The |
| latter two arrays must be large enough to hold the maximum number |
| of code lengths, which RFC 1951 defines as 286 + 30. */ |
| |
| #define ZDEBUG_TABLE_SIZE \ |
| (2 * HUFFMAN_TABLE_SIZE * sizeof (uint16_t) \ |
| + (286 + 30) * sizeof (uint16_t) \ |
| + (286 + 30) * sizeof (unsigned char)) |
| |
| #define ZDEBUG_TABLE_CODELEN_OFFSET \ |
| (2 * HUFFMAN_TABLE_SIZE * sizeof (uint16_t) \ |
| + (286 + 30) * sizeof (uint16_t)) |
| |
| #define ZDEBUG_TABLE_WORK_OFFSET \ |
| (2 * HUFFMAN_TABLE_SIZE * sizeof (uint16_t)) |
| |
| #ifdef BACKTRACE_GENERATE_FIXED_HUFFMAN_TABLE |
| |
| /* Used by the main function that generates the fixed table to learn |
| the table size. */ |
| static size_t final_next_secondary; |
| |
| #endif |
| |
| /* Build a Huffman code table from an array of lengths in CODES of |
| length CODES_LEN. The table is stored into *TABLE. ZDEBUG_TABLE |
| is the same as for elf_zlib_inflate, used to find some work space. |
| Returns 1 on success, 0 on error. */ |
| |
| static int |
| elf_zlib_inflate_table (unsigned char *codes, size_t codes_len, |
| uint16_t *zdebug_table, uint16_t *table) |
| { |
| uint16_t count[16]; |
| uint16_t start[16]; |
| uint16_t prev[16]; |
| uint16_t firstcode[7]; |
| uint16_t *next; |
| size_t i; |
| size_t j; |
| unsigned int code; |
| size_t next_secondary; |
| |
| /* Count the number of code of each length. Set NEXT[val] to be the |
| next value after VAL with the same bit length. */ |
| |
| next = (uint16_t *) (((unsigned char *) zdebug_table) |
| + ZDEBUG_TABLE_WORK_OFFSET); |
| |
| memset (&count[0], 0, 16 * sizeof (uint16_t)); |
| for (i = 0; i < codes_len; ++i) |
| { |
| if (unlikely (codes[i] >= 16)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| if (count[codes[i]] == 0) |
| { |
| start[codes[i]] = i; |
| prev[codes[i]] = i; |
| } |
| else |
| { |
| next[prev[codes[i]]] = i; |
| prev[codes[i]] = i; |
| } |
| |
| ++count[codes[i]]; |
| } |
| |
| /* For each length, fill in the table for the codes of that |
| length. */ |
| |
| memset (table, 0, HUFFMAN_TABLE_SIZE * sizeof (uint16_t)); |
| |
| /* Handle the values that do not require a secondary table. */ |
| |
| code = 0; |
| for (j = 1; j <= 8; ++j) |
| { |
| unsigned int jcnt; |
| unsigned int val; |
| |
| jcnt = count[j]; |
| if (jcnt == 0) |
| continue; |
| |
| if (unlikely (jcnt > (1U << j))) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| /* There are JCNT values that have this length, the values |
| starting from START[j] continuing through NEXT[VAL]. Those |
| values are assigned consecutive values starting at CODE. */ |
| |
| val = start[j]; |
| for (i = 0; i < jcnt; ++i) |
| { |
| uint16_t tval; |
| size_t ind; |
| unsigned int incr; |
| |
| /* In the compressed bit stream, the value VAL is encoded as |
| J bits with the value C. */ |
| |
| if (unlikely ((val & ~HUFFMAN_VALUE_MASK) != 0)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| tval = val | ((j - 1) << HUFFMAN_BITS_SHIFT); |
| |
| /* The table lookup uses 8 bits. If J is less than 8, we |
| don't know what the other bits will be. We need to fill |
| in all possibilities in the table. Since the Huffman |
| code is unambiguous, those entries can't be used for any |
| other code. */ |
| |
| for (ind = code; ind < 0x100; ind += 1 << j) |
| { |
| if (unlikely (table[ind] != 0)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| table[ind] = tval; |
| } |
| |
| /* Advance to the next value with this length. */ |
| if (i + 1 < jcnt) |
| val = next[val]; |
| |
| /* The Huffman codes are stored in the bitstream with the |
| most significant bit first, as is required to make them |
| unambiguous. The effect is that when we read them from |
| the bitstream we see the bit sequence in reverse order: |
| the most significant bit of the Huffman code is the least |
| significant bit of the value we read from the bitstream. |
| That means that to make our table lookups work, we need |
| to reverse the bits of CODE. Since reversing bits is |
| tedious and in general requires using a table, we instead |
| increment CODE in reverse order. That is, if the number |
| of bits we are currently using, here named J, is 3, we |
| count as 000, 100, 010, 110, 001, 101, 011, 111, which is |
| to say the numbers from 0 to 7 but with the bits |
| reversed. Going to more bits, aka incrementing J, |
| effectively just adds more zero bits as the beginning, |
| and as such does not change the numeric value of CODE. |
| |
| To increment CODE of length J in reverse order, find the |
| most significant zero bit and set it to one while |
| clearing all higher bits. In other words, add 1 modulo |
| 2^J, only reversed. */ |
| |
| incr = 1U << (j - 1); |
| while ((code & incr) != 0) |
| incr >>= 1; |
| if (incr == 0) |
| code = 0; |
| else |
| { |
| code &= incr - 1; |
| code += incr; |
| } |
| } |
| } |
| |
| /* Handle the values that require a secondary table. */ |
| |
| /* Set FIRSTCODE, the number at which the codes start, for each |
| length. */ |
| |
| for (j = 9; j < 16; j++) |
| { |
| unsigned int jcnt; |
| unsigned int k; |
| |
| jcnt = count[j]; |
| if (jcnt == 0) |
| continue; |
| |
| /* There are JCNT values that have this length, the values |
| starting from START[j]. Those values are assigned |
| consecutive values starting at CODE. */ |
| |
| firstcode[j - 9] = code; |
| |
| /* Reverse add JCNT to CODE modulo 2^J. */ |
| for (k = 0; k < j; ++k) |
| { |
| if ((jcnt & (1U << k)) != 0) |
| { |
| unsigned int m; |
| unsigned int bit; |
| |
| bit = 1U << (j - k - 1); |
| for (m = 0; m < j - k; ++m, bit >>= 1) |
| { |
| if ((code & bit) == 0) |
| { |
| code += bit; |
| break; |
| } |
| code &= ~bit; |
| } |
| jcnt &= ~(1U << k); |
| } |
| } |
| if (unlikely (jcnt != 0)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| } |
| |
| /* For J from 9 to 15, inclusive, we store COUNT[J] consecutive |
| values starting at START[J] with consecutive codes starting at |
| FIRSTCODE[J - 9]. In the primary table we need to point to the |
| secondary table, and the secondary table will be indexed by J - 9 |
| bits. We count down from 15 so that we install the larger |
| secondary tables first, as the smaller ones may be embedded in |
| the larger ones. */ |
| |
| next_secondary = 0; /* Index of next secondary table (after primary). */ |
| for (j = 15; j >= 9; j--) |
| { |
| unsigned int jcnt; |
| unsigned int val; |
| size_t primary; /* Current primary index. */ |
| size_t secondary; /* Offset to current secondary table. */ |
| size_t secondary_bits; /* Bit size of current secondary table. */ |
| |
| jcnt = count[j]; |
| if (jcnt == 0) |
| continue; |
| |
| val = start[j]; |
| code = firstcode[j - 9]; |
| primary = 0x100; |
| secondary = 0; |
| secondary_bits = 0; |
| for (i = 0; i < jcnt; ++i) |
| { |
| uint16_t tval; |
| size_t ind; |
| unsigned int incr; |
| |
| if ((code & 0xff) != primary) |
| { |
| uint16_t tprimary; |
| |
| /* Fill in a new primary table entry. */ |
| |
| primary = code & 0xff; |
| |
| tprimary = table[primary]; |
| if (tprimary == 0) |
| { |
| /* Start a new secondary table. */ |
| |
| if (unlikely ((next_secondary & HUFFMAN_VALUE_MASK) |
| != next_secondary)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| secondary = next_secondary; |
| secondary_bits = j - 8; |
| next_secondary += 1 << secondary_bits; |
| table[primary] = (secondary |
| + ((j - 8) << HUFFMAN_BITS_SHIFT) |
| + (1U << HUFFMAN_SECONDARY_SHIFT)); |
| } |
| else |
| { |
| /* There is an existing entry. It had better be a |
| secondary table with enough bits. */ |
| if (unlikely ((tprimary & (1U << HUFFMAN_SECONDARY_SHIFT)) |
| == 0)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| secondary = tprimary & HUFFMAN_VALUE_MASK; |
| secondary_bits = ((tprimary >> HUFFMAN_BITS_SHIFT) |
| & HUFFMAN_BITS_MASK); |
| if (unlikely (secondary_bits < j - 8)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| } |
| } |
| |
| /* Fill in secondary table entries. */ |
| |
| tval = val | ((j - 8) << HUFFMAN_BITS_SHIFT); |
| |
| for (ind = code >> 8; |
| ind < (1U << secondary_bits); |
| ind += 1U << (j - 8)) |
| { |
| if (unlikely (table[secondary + 0x100 + ind] != 0)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| table[secondary + 0x100 + ind] = tval; |
| } |
| |
| if (i + 1 < jcnt) |
| val = next[val]; |
| |
| incr = 1U << (j - 1); |
| while ((code & incr) != 0) |
| incr >>= 1; |
| if (incr == 0) |
| code = 0; |
| else |
| { |
| code &= incr - 1; |
| code += incr; |
| } |
| } |
| } |
| |
| #ifdef BACKTRACE_GENERATE_FIXED_HUFFMAN_TABLE |
| final_next_secondary = next_secondary; |
| #endif |
| |
| return 1; |
| } |
| |
| #ifdef BACKTRACE_GENERATE_FIXED_HUFFMAN_TABLE |
| |
| /* Used to generate the fixed Huffman table for block type 1. */ |
| |
| #include <stdio.h> |
| |
| static uint16_t table[ZDEBUG_TABLE_SIZE]; |
| static unsigned char codes[288]; |
| |
| int |
| main () |
| { |
| size_t i; |
| |
| for (i = 0; i <= 143; ++i) |
| codes[i] = 8; |
| for (i = 144; i <= 255; ++i) |
| codes[i] = 9; |
| for (i = 256; i <= 279; ++i) |
| codes[i] = 7; |
| for (i = 280; i <= 287; ++i) |
| codes[i] = 8; |
| if (!elf_zlib_inflate_table (&codes[0], 288, &table[0], &table[0])) |
| { |
| fprintf (stderr, "elf_zlib_inflate_table failed\n"); |
| exit (EXIT_FAILURE); |
| } |
| |
| printf ("static const uint16_t elf_zlib_default_table[%#zx] =\n", |
| final_next_secondary + 0x100); |
| printf ("{\n"); |
| for (i = 0; i < final_next_secondary + 0x100; i += 8) |
| { |
| size_t j; |
| |
| printf (" "); |
| for (j = i; j < final_next_secondary + 0x100 && j < i + 8; ++j) |
| printf (" %#x,", table[j]); |
| printf ("\n"); |
| } |
| printf ("};\n"); |
| printf ("\n"); |
| |
| for (i = 0; i < 32; ++i) |
| codes[i] = 5; |
| if (!elf_zlib_inflate_table (&codes[0], 32, &table[0], &table[0])) |
| { |
| fprintf (stderr, "elf_zlib_inflate_table failed\n"); |
| exit (EXIT_FAILURE); |
| } |
| |
| printf ("static const uint16_t elf_zlib_default_dist_table[%#zx] =\n", |
| final_next_secondary + 0x100); |
| printf ("{\n"); |
| for (i = 0; i < final_next_secondary + 0x100; i += 8) |
| { |
| size_t j; |
| |
| printf (" "); |
| for (j = i; j < final_next_secondary + 0x100 && j < i + 8; ++j) |
| printf (" %#x,", table[j]); |
| printf ("\n"); |
| } |
| printf ("};\n"); |
| |
| return 0; |
| } |
| |
| #endif |
| |
| /* The fixed tables generated by the #ifdef'ed out main function |
| above. */ |
| |
| static const uint16_t elf_zlib_default_table[0x170] = |
| { |
| 0xd00, 0xe50, 0xe10, 0xf18, 0xd10, 0xe70, 0xe30, 0x1230, |
| 0xd08, 0xe60, 0xe20, 0x1210, 0xe00, 0xe80, 0xe40, 0x1250, |
| 0xd04, 0xe58, 0xe18, 0x1200, 0xd14, 0xe78, 0xe38, 0x1240, |
| 0xd0c, 0xe68, 0xe28, 0x1220, 0xe08, 0xe88, 0xe48, 0x1260, |
| 0xd02, 0xe54, 0xe14, 0xf1c, 0xd12, 0xe74, 0xe34, 0x1238, |
| 0xd0a, 0xe64, 0xe24, 0x1218, 0xe04, 0xe84, 0xe44, 0x1258, |
| 0xd06, 0xe5c, 0xe1c, 0x1208, 0xd16, 0xe7c, 0xe3c, 0x1248, |
| 0xd0e, 0xe6c, 0xe2c, 0x1228, 0xe0c, 0xe8c, 0xe4c, 0x1268, |
| 0xd01, 0xe52, 0xe12, 0xf1a, 0xd11, 0xe72, 0xe32, 0x1234, |
| 0xd09, 0xe62, 0xe22, 0x1214, 0xe02, 0xe82, 0xe42, 0x1254, |
| 0xd05, 0xe5a, 0xe1a, 0x1204, 0xd15, 0xe7a, 0xe3a, 0x1244, |
| 0xd0d, 0xe6a, 0xe2a, 0x1224, 0xe0a, 0xe8a, 0xe4a, 0x1264, |
| 0xd03, 0xe56, 0xe16, 0xf1e, 0xd13, 0xe76, 0xe36, 0x123c, |
| 0xd0b, 0xe66, 0xe26, 0x121c, 0xe06, 0xe86, 0xe46, 0x125c, |
| 0xd07, 0xe5e, 0xe1e, 0x120c, 0xd17, 0xe7e, 0xe3e, 0x124c, |
| 0xd0f, 0xe6e, 0xe2e, 0x122c, 0xe0e, 0xe8e, 0xe4e, 0x126c, |
| 0xd00, 0xe51, 0xe11, 0xf19, 0xd10, 0xe71, 0xe31, 0x1232, |
| 0xd08, 0xe61, 0xe21, 0x1212, 0xe01, 0xe81, 0xe41, 0x1252, |
| 0xd04, 0xe59, 0xe19, 0x1202, 0xd14, 0xe79, 0xe39, 0x1242, |
| 0xd0c, 0xe69, 0xe29, 0x1222, 0xe09, 0xe89, 0xe49, 0x1262, |
| 0xd02, 0xe55, 0xe15, 0xf1d, 0xd12, 0xe75, 0xe35, 0x123a, |
| 0xd0a, 0xe65, 0xe25, 0x121a, 0xe05, 0xe85, 0xe45, 0x125a, |
| 0xd06, 0xe5d, 0xe1d, 0x120a, 0xd16, 0xe7d, 0xe3d, 0x124a, |
| 0xd0e, 0xe6d, 0xe2d, 0x122a, 0xe0d, 0xe8d, 0xe4d, 0x126a, |
| 0xd01, 0xe53, 0xe13, 0xf1b, 0xd11, 0xe73, 0xe33, 0x1236, |
| 0xd09, 0xe63, 0xe23, 0x1216, 0xe03, 0xe83, 0xe43, 0x1256, |
| 0xd05, 0xe5b, 0xe1b, 0x1206, 0xd15, 0xe7b, 0xe3b, 0x1246, |
| 0xd0d, 0xe6b, 0xe2b, 0x1226, 0xe0b, 0xe8b, 0xe4b, 0x1266, |
| 0xd03, 0xe57, 0xe17, 0xf1f, 0xd13, 0xe77, 0xe37, 0x123e, |
| 0xd0b, 0xe67, 0xe27, 0x121e, 0xe07, 0xe87, 0xe47, 0x125e, |
| 0xd07, 0xe5f, 0xe1f, 0x120e, 0xd17, 0xe7f, 0xe3f, 0x124e, |
| 0xd0f, 0xe6f, 0xe2f, 0x122e, 0xe0f, 0xe8f, 0xe4f, 0x126e, |
| 0x290, 0x291, 0x292, 0x293, 0x294, 0x295, 0x296, 0x297, |
| 0x298, 0x299, 0x29a, 0x29b, 0x29c, 0x29d, 0x29e, 0x29f, |
| 0x2a0, 0x2a1, 0x2a2, 0x2a3, 0x2a4, 0x2a5, 0x2a6, 0x2a7, |
| 0x2a8, 0x2a9, 0x2aa, 0x2ab, 0x2ac, 0x2ad, 0x2ae, 0x2af, |
| 0x2b0, 0x2b1, 0x2b2, 0x2b3, 0x2b4, 0x2b5, 0x2b6, 0x2b7, |
| 0x2b8, 0x2b9, 0x2ba, 0x2bb, 0x2bc, 0x2bd, 0x2be, 0x2bf, |
| 0x2c0, 0x2c1, 0x2c2, 0x2c3, 0x2c4, 0x2c5, 0x2c6, 0x2c7, |
| 0x2c8, 0x2c9, 0x2ca, 0x2cb, 0x2cc, 0x2cd, 0x2ce, 0x2cf, |
| 0x2d0, 0x2d1, 0x2d2, 0x2d3, 0x2d4, 0x2d5, 0x2d6, 0x2d7, |
| 0x2d8, 0x2d9, 0x2da, 0x2db, 0x2dc, 0x2dd, 0x2de, 0x2df, |
| 0x2e0, 0x2e1, 0x2e2, 0x2e3, 0x2e4, 0x2e5, 0x2e6, 0x2e7, |
| 0x2e8, 0x2e9, 0x2ea, 0x2eb, 0x2ec, 0x2ed, 0x2ee, 0x2ef, |
| 0x2f0, 0x2f1, 0x2f2, 0x2f3, 0x2f4, 0x2f5, 0x2f6, 0x2f7, |
| 0x2f8, 0x2f9, 0x2fa, 0x2fb, 0x2fc, 0x2fd, 0x2fe, 0x2ff, |
| }; |
| |
| static const uint16_t elf_zlib_default_dist_table[0x100] = |
| { |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| 0x800, 0x810, 0x808, 0x818, 0x804, 0x814, 0x80c, 0x81c, |
| 0x802, 0x812, 0x80a, 0x81a, 0x806, 0x816, 0x80e, 0x81e, |
| 0x801, 0x811, 0x809, 0x819, 0x805, 0x815, 0x80d, 0x81d, |
| 0x803, 0x813, 0x80b, 0x81b, 0x807, 0x817, 0x80f, 0x81f, |
| }; |
| |
| /* Inflate a zlib stream from PIN/SIN to POUT/SOUT. Return 1 on |
| success, 0 on some error parsing the stream. */ |
| |
| static int |
| elf_zlib_inflate (const unsigned char *pin, size_t sin, uint16_t *zdebug_table, |
| unsigned char *pout, size_t sout) |
| { |
| unsigned char *porigout; |
| const unsigned char *pinend; |
| unsigned char *poutend; |
| |
| /* We can apparently see multiple zlib streams concatenated |
| together, so keep going as long as there is something to read. |
| The last 4 bytes are the checksum. */ |
| porigout = pout; |
| pinend = pin + sin; |
| poutend = pout + sout; |
| while ((pinend - pin) > 4) |
| { |
| uint64_t val; |
| unsigned int bits; |
| int last; |
| |
| /* Read the two byte zlib header. */ |
| |
| if (unlikely ((pin[0] & 0xf) != 8)) /* 8 is zlib encoding. */ |
| { |
| /* Unknown compression method. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| if (unlikely ((pin[0] >> 4) > 7)) |
| { |
| /* Window size too large. Other than this check, we don't |
| care about the window size. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| if (unlikely ((pin[1] & 0x20) != 0)) |
| { |
| /* Stream expects a predefined dictionary, but we have no |
| dictionary. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| val = (pin[0] << 8) | pin[1]; |
| if (unlikely (val % 31 != 0)) |
| { |
| /* Header check failure. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| pin += 2; |
| |
| /* Align PIN to a 32-bit boundary. */ |
| |
| val = 0; |
| bits = 0; |
| while ((((uintptr_t) pin) & 3) != 0) |
| { |
| val |= (uint64_t)*pin << bits; |
| bits += 8; |
| ++pin; |
| } |
| |
| /* Read blocks until one is marked last. */ |
| |
| last = 0; |
| |
| while (!last) |
| { |
| unsigned int type; |
| const uint16_t *tlit; |
| const uint16_t *tdist; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| last = val & 1; |
| type = (val >> 1) & 3; |
| val >>= 3; |
| bits -= 3; |
| |
| if (unlikely (type == 3)) |
| { |
| /* Invalid block type. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| if (type == 0) |
| { |
| uint16_t len; |
| uint16_t lenc; |
| |
| /* An uncompressed block. */ |
| |
| /* If we've read ahead more than a byte, back up. */ |
| while (bits > 8) |
| { |
| --pin; |
| bits -= 8; |
| } |
| |
| val = 0; |
| bits = 0; |
| if (unlikely ((pinend - pin) < 4)) |
| { |
| /* Missing length. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| len = pin[0] | (pin[1] << 8); |
| lenc = pin[2] | (pin[3] << 8); |
| pin += 4; |
| lenc = ~lenc; |
| if (unlikely (len != lenc)) |
| { |
| /* Corrupt data. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| if (unlikely (len > (unsigned int) (pinend - pin) |
| || len > (unsigned int) (poutend - pout))) |
| { |
| /* Not enough space in buffers. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| memcpy (pout, pin, len); |
| pout += len; |
| pin += len; |
| |
| /* Align PIN. */ |
| while ((((uintptr_t) pin) & 3) != 0) |
| { |
| val |= (uint64_t)*pin << bits; |
| bits += 8; |
| ++pin; |
| } |
| |
| /* Go around to read the next block. */ |
| continue; |
| } |
| |
| if (type == 1) |
| { |
| tlit = elf_zlib_default_table; |
| tdist = elf_zlib_default_dist_table; |
| } |
| else |
| { |
| unsigned int nlit; |
| unsigned int ndist; |
| unsigned int nclen; |
| unsigned char codebits[19]; |
| unsigned char *plenbase; |
| unsigned char *plen; |
| unsigned char *plenend; |
| |
| /* Read a Huffman encoding table. The various magic |
| numbers here are from RFC 1951. */ |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| nlit = (val & 0x1f) + 257; |
| val >>= 5; |
| ndist = (val & 0x1f) + 1; |
| val >>= 5; |
| nclen = (val & 0xf) + 4; |
| val >>= 4; |
| bits -= 14; |
| if (unlikely (nlit > 286 || ndist > 30)) |
| { |
| /* Values out of range. */ |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| /* Read and build the table used to compress the |
| literal, length, and distance codes. */ |
| |
| memset(&codebits[0], 0, 19); |
| |
| /* There are always at least 4 elements in the |
| table. */ |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| codebits[16] = val & 7; |
| codebits[17] = (val >> 3) & 7; |
| codebits[18] = (val >> 6) & 7; |
| codebits[0] = (val >> 9) & 7; |
| val >>= 12; |
| bits -= 12; |
| |
| if (nclen == 4) |
| goto codebitsdone; |
| |
| codebits[8] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 5) |
| goto codebitsdone; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| codebits[7] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 6) |
| goto codebitsdone; |
| |
| codebits[9] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 7) |
| goto codebitsdone; |
| |
| codebits[6] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 8) |
| goto codebitsdone; |
| |
| codebits[10] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 9) |
| goto codebitsdone; |
| |
| codebits[5] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 10) |
| goto codebitsdone; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| codebits[11] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 11) |
| goto codebitsdone; |
| |
| codebits[4] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 12) |
| goto codebitsdone; |
| |
| codebits[12] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 13) |
| goto codebitsdone; |
| |
| codebits[3] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 14) |
| goto codebitsdone; |
| |
| codebits[13] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 15) |
| goto codebitsdone; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| codebits[2] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 16) |
| goto codebitsdone; |
| |
| codebits[14] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 17) |
| goto codebitsdone; |
| |
| codebits[1] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| if (nclen == 18) |
| goto codebitsdone; |
| |
| codebits[15] = val & 7; |
| val >>= 3; |
| bits -= 3; |
| |
| codebitsdone: |
| |
| if (!elf_zlib_inflate_table (codebits, 19, zdebug_table, |
| zdebug_table)) |
| return 0; |
| |
| /* Read the compressed bit lengths of the literal, |
| length, and distance codes. We have allocated space |
| at the end of zdebug_table to hold them. */ |
| |
| plenbase = (((unsigned char *) zdebug_table) |
| + ZDEBUG_TABLE_CODELEN_OFFSET); |
| plen = plenbase; |
| plenend = plen + nlit + ndist; |
| while (plen < plenend) |
| { |
| uint16_t t; |
| unsigned int b; |
| uint16_t v; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| t = zdebug_table[val & 0xff]; |
| |
| /* The compression here uses bit lengths up to 7, so |
| a secondary table is never necessary. */ |
| if (unlikely ((t & (1U << HUFFMAN_SECONDARY_SHIFT)) != 0)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| b = (t >> HUFFMAN_BITS_SHIFT) & HUFFMAN_BITS_MASK; |
| val >>= b + 1; |
| bits -= b + 1; |
| |
| v = t & HUFFMAN_VALUE_MASK; |
| if (v < 16) |
| *plen++ = v; |
| else if (v == 16) |
| { |
| unsigned int c; |
| unsigned int prev; |
| |
| /* Copy previous entry 3 to 6 times. */ |
| |
| if (unlikely (plen == plenbase)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| /* We used up to 7 bits since the last |
| elf_zlib_fetch, so we have at least 8 bits |
| available here. */ |
| |
| c = 3 + (val & 0x3); |
| val >>= 2; |
| bits -= 2; |
| if (unlikely ((unsigned int) (plenend - plen) < c)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| prev = plen[-1]; |
| switch (c) |
| { |
| case 6: |
| *plen++ = prev; |
| ATTRIBUTE_FALLTHROUGH; |
| case 5: |
| *plen++ = prev; |
| ATTRIBUTE_FALLTHROUGH; |
| case 4: |
| *plen++ = prev; |
| } |
| *plen++ = prev; |
| *plen++ = prev; |
| *plen++ = prev; |
| } |
| else if (v == 17) |
| { |
| unsigned int c; |
| |
| /* Store zero 3 to 10 times. */ |
| |
| /* We used up to 7 bits since the last |
| elf_zlib_fetch, so we have at least 8 bits |
| available here. */ |
| |
| c = 3 + (val & 0x7); |
| val >>= 3; |
| bits -= 3; |
| if (unlikely ((unsigned int) (plenend - plen) < c)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| switch (c) |
| { |
| case 10: |
| *plen++ = 0; |
| ATTRIBUTE_FALLTHROUGH; |
| case 9: |
| *plen++ = 0; |
| ATTRIBUTE_FALLTHROUGH; |
| case 8: |
| *plen++ = 0; |
| ATTRIBUTE_FALLTHROUGH; |
| case 7: |
| *plen++ = 0; |
| ATTRIBUTE_FALLTHROUGH; |
| case 6: |
| *plen++ = 0; |
| ATTRIBUTE_FALLTHROUGH; |
| case 5: |
| *plen++ = 0; |
| ATTRIBUTE_FALLTHROUGH; |
| case 4: |
| *plen++ = 0; |
| } |
| *plen++ = 0; |
| *plen++ = 0; |
| *plen++ = 0; |
| } |
| else if (v == 18) |
| { |
| unsigned int c; |
| |
| /* Store zero 11 to 138 times. */ |
| |
| /* We used up to 7 bits since the last |
| elf_zlib_fetch, so we have at least 8 bits |
| available here. */ |
| |
| c = 11 + (val & 0x7f); |
| val >>= 7; |
| bits -= 7; |
| if (unlikely ((unsigned int) (plenend - plen) < c)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| memset (plen, 0, c); |
| plen += c; |
| } |
| else |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| } |
| |
| /* Make sure that the stop code can appear. */ |
| |
| plen = plenbase; |
| if (unlikely (plen[256] == 0)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| /* Build the decompression tables. */ |
| |
| if (!elf_zlib_inflate_table (plen, nlit, zdebug_table, |
| zdebug_table)) |
| return 0; |
| if (!elf_zlib_inflate_table (plen + nlit, ndist, zdebug_table, |
| zdebug_table + HUFFMAN_TABLE_SIZE)) |
| return 0; |
| tlit = zdebug_table; |
| tdist = zdebug_table + HUFFMAN_TABLE_SIZE; |
| } |
| |
| /* Inflate values until the end of the block. This is the |
| main loop of the inflation code. */ |
| |
| while (1) |
| { |
| uint16_t t; |
| unsigned int b; |
| uint16_t v; |
| unsigned int lit; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| t = tlit[val & 0xff]; |
| b = (t >> HUFFMAN_BITS_SHIFT) & HUFFMAN_BITS_MASK; |
| v = t & HUFFMAN_VALUE_MASK; |
| |
| if ((t & (1U << HUFFMAN_SECONDARY_SHIFT)) == 0) |
| { |
| lit = v; |
| val >>= b + 1; |
| bits -= b + 1; |
| } |
| else |
| { |
| t = tlit[v + 0x100 + ((val >> 8) & ((1U << b) - 1))]; |
| b = (t >> HUFFMAN_BITS_SHIFT) & HUFFMAN_BITS_MASK; |
| lit = t & HUFFMAN_VALUE_MASK; |
| val >>= b + 8; |
| bits -= b + 8; |
| } |
| |
| if (lit < 256) |
| { |
| if (unlikely (pout == poutend)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| *pout++ = lit; |
| |
| /* We will need to write the next byte soon. We ask |
| for high temporal locality because we will write |
| to the whole cache line soon. */ |
| __builtin_prefetch (pout, 1, 3); |
| } |
| else if (lit == 256) |
| { |
| /* The end of the block. */ |
| break; |
| } |
| else |
| { |
| unsigned int dist; |
| unsigned int len; |
| |
| /* Convert lit into a length. */ |
| |
| if (lit < 265) |
| len = lit - 257 + 3; |
| else if (lit == 285) |
| len = 258; |
| else if (unlikely (lit > 285)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| else |
| { |
| unsigned int extra; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| /* This is an expression for the table of length |
| codes in RFC 1951 3.2.5. */ |
| lit -= 265; |
| extra = (lit >> 2) + 1; |
| len = (lit & 3) << extra; |
| len += 11; |
| len += ((1U << (extra - 1)) - 1) << 3; |
| len += val & ((1U << extra) - 1); |
| val >>= extra; |
| bits -= extra; |
| } |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| t = tdist[val & 0xff]; |
| b = (t >> HUFFMAN_BITS_SHIFT) & HUFFMAN_BITS_MASK; |
| v = t & HUFFMAN_VALUE_MASK; |
| |
| if ((t & (1U << HUFFMAN_SECONDARY_SHIFT)) == 0) |
| { |
| dist = v; |
| val >>= b + 1; |
| bits -= b + 1; |
| } |
| else |
| { |
| t = tdist[v + 0x100 + ((val >> 8) & ((1U << b) - 1))]; |
| b = (t >> HUFFMAN_BITS_SHIFT) & HUFFMAN_BITS_MASK; |
| dist = t & HUFFMAN_VALUE_MASK; |
| val >>= b + 8; |
| bits -= b + 8; |
| } |
| |
| /* Convert dist to a distance. */ |
| |
| if (dist == 0) |
| { |
| /* A distance of 1. A common case, meaning |
| repeat the last character LEN times. */ |
| |
| if (unlikely (pout == porigout)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| if (unlikely ((unsigned int) (poutend - pout) < len)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| memset (pout, pout[-1], len); |
| pout += len; |
| } |
| else if (unlikely (dist > 29)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| else |
| { |
| if (dist < 4) |
| dist = dist + 1; |
| else |
| { |
| unsigned int extra; |
| |
| if (!elf_zlib_fetch (&pin, pinend, &val, &bits)) |
| return 0; |
| |
| /* This is an expression for the table of |
| distance codes in RFC 1951 3.2.5. */ |
| dist -= 4; |
| extra = (dist >> 1) + 1; |
| dist = (dist & 1) << extra; |
| dist += 5; |
| dist += ((1U << (extra - 1)) - 1) << 2; |
| dist += val & ((1U << extra) - 1); |
| val >>= extra; |
| bits -= extra; |
| } |
| |
| /* Go back dist bytes, and copy len bytes from |
| there. */ |
| |
| if (unlikely ((unsigned int) (pout - porigout) < dist)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| if (unlikely ((unsigned int) (poutend - pout) < len)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| if (dist >= len) |
| { |
| memcpy (pout, pout - dist, len); |
| pout += len; |
| } |
| else |
| { |
| while (len > 0) |
| { |
| unsigned int copy; |
| |
| copy = len < dist ? len : dist; |
| memcpy (pout, pout - dist, copy); |
| len -= copy; |
| pout += copy; |
| } |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| /* We should have filled the output buffer. */ |
| if (unlikely (pout != poutend)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* Verify the zlib checksum. The checksum is in the 4 bytes at |
| CHECKBYTES, and the uncompressed data is at UNCOMPRESSED / |
| UNCOMPRESSED_SIZE. Returns 1 on success, 0 on failure. */ |
| |
| static int |
| elf_zlib_verify_checksum (const unsigned char *checkbytes, |
| const unsigned char *uncompressed, |
| size_t uncompressed_size) |
| { |
| unsigned int i; |
| unsigned int cksum; |
| const unsigned char *p; |
| uint32_t s1; |
| uint32_t s2; |
| size_t hsz; |
| |
| cksum = 0; |
| for (i = 0; i < 4; i++) |
| cksum = (cksum << 8) | checkbytes[i]; |
| |
| s1 = 1; |
| s2 = 0; |
| |
| /* Minimize modulo operations. */ |
| |
| p = uncompressed; |
| hsz = uncompressed_size; |
| while (hsz >= 5552) |
| { |
| for (i = 0; i < 5552; i += 16) |
| { |
| /* Manually unroll loop 16 times. */ |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| } |
| hsz -= 5552; |
| s1 %= 65521; |
| s2 %= 65521; |
| } |
| |
| while (hsz >= 16) |
| { |
| /* Manually unroll loop 16 times. */ |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| |
| hsz -= 16; |
| } |
| |
| for (i = 0; i < hsz; ++i) |
| { |
| s1 = s1 + *p++; |
| s2 = s2 + s1; |
| } |
| |
| s1 %= 65521; |
| s2 %= 65521; |
| |
| if (unlikely ((s2 << 16) + s1 != cksum)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* Inflate a zlib stream from PIN/SIN to POUT/SOUT, and verify the |
| checksum. Return 1 on success, 0 on error. */ |
| |
| static int |
| elf_zlib_inflate_and_verify (const unsigned char *pin, size_t sin, |
| uint16_t *zdebug_table, unsigned char *pout, |
| size_t sout) |
| { |
| if (!elf_zlib_inflate (pin, sin, zdebug_table, pout, sout)) |
| return 0; |
| if (!elf_zlib_verify_checksum (pin + sin - 4, pout, sout)) |
| return 0; |
| return 1; |
| } |
| |
| /* Uncompress the old compressed debug format, the one emitted by |
| --compress-debug-sections=zlib-gnu. The compressed data is in |
| COMPRESSED / COMPRESSED_SIZE, and the function writes to |
| *UNCOMPRESSED / *UNCOMPRESSED_SIZE. ZDEBUG_TABLE is work space to |
| hold Huffman tables. Returns 0 on error, 1 on successful |
| decompression or if something goes wrong. In general we try to |
| carry on, by returning 1, even if we can't decompress. */ |
| |
| static int |
| elf_uncompress_zdebug (struct backtrace_state *state, |
| const unsigned char *compressed, size_t compressed_size, |
| uint16_t *zdebug_table, |
| backtrace_error_callback error_callback, void *data, |
| unsigned char **uncompressed, size_t *uncompressed_size) |
| { |
| size_t sz; |
| size_t i; |
| unsigned char *po; |
| |
| *uncompressed = NULL; |
| *uncompressed_size = 0; |
| |
| /* The format starts with the four bytes ZLIB, followed by the 8 |
| byte length of the uncompressed data in big-endian order, |
| followed by a zlib stream. */ |
| |
| if (compressed_size < 12 || memcmp (compressed, "ZLIB", 4) != 0) |
| return 1; |
| |
| sz = 0; |
| for (i = 0; i < 8; i++) |
| sz = (sz << 8) | compressed[i + 4]; |
| |
| if (*uncompressed != NULL && *uncompressed_size >= sz) |
| po = *uncompressed; |
| else |
| { |
| po = (unsigned char *) backtrace_alloc (state, sz, error_callback, data); |
| if (po == NULL) |
| return 0; |
| } |
| |
| if (!elf_zlib_inflate_and_verify (compressed + 12, compressed_size - 12, |
| zdebug_table, po, sz)) |
| return 1; |
| |
| *uncompressed = po; |
| *uncompressed_size = sz; |
| |
| return 1; |
| } |
| |
| /* Uncompress the new compressed debug format, the official standard |
| ELF approach emitted by --compress-debug-sections=zlib-gabi. The |
| compressed data is in COMPRESSED / COMPRESSED_SIZE, and the |
| function writes to *UNCOMPRESSED / *UNCOMPRESSED_SIZE. |
| ZDEBUG_TABLE is work space as for elf_uncompress_zdebug. Returns 0 |
| on error, 1 on successful decompression or if something goes wrong. |
| In general we try to carry on, by returning 1, even if we can't |
| decompress. */ |
| |
| static int |
| elf_uncompress_chdr (struct backtrace_state *state, |
| const unsigned char *compressed, size_t compressed_size, |
| uint16_t *zdebug_table, |
| backtrace_error_callback error_callback, void *data, |
| unsigned char **uncompressed, size_t *uncompressed_size) |
| { |
| const b_elf_chdr *chdr; |
| unsigned char *po; |
| |
| *uncompressed = NULL; |
| *uncompressed_size = 0; |
| |
| /* The format starts with an ELF compression header. */ |
| if (compressed_size < sizeof (b_elf_chdr)) |
| return 1; |
| |
| chdr = (const b_elf_chdr *) compressed; |
| |
| if (chdr->ch_type != ELFCOMPRESS_ZLIB) |
| { |
| /* Unsupported compression algorithm. */ |
| return 1; |
| } |
| |
| if (*uncompressed != NULL && *uncompressed_size >= chdr->ch_size) |
| po = *uncompressed; |
| else |
| { |
| po = (unsigned char *) backtrace_alloc (state, chdr->ch_size, |
| error_callback, data); |
| if (po == NULL) |
| return 0; |
| } |
| |
| if (!elf_zlib_inflate_and_verify (compressed + sizeof (b_elf_chdr), |
| compressed_size - sizeof (b_elf_chdr), |
| zdebug_table, po, chdr->ch_size)) |
| return 1; |
| |
| *uncompressed = po; |
| *uncompressed_size = chdr->ch_size; |
| |
| return 1; |
| } |
| |
| /* This function is a hook for testing the zlib support. It is only |
| used by tests. */ |
| |
| int |
| backtrace_uncompress_zdebug (struct backtrace_state *state, |
| const unsigned char *compressed, |
| size_t compressed_size, |
| backtrace_error_callback error_callback, |
| void *data, unsigned char **uncompressed, |
| size_t *uncompressed_size) |
| { |
| uint16_t *zdebug_table; |
| int ret; |
| |
| zdebug_table = ((uint16_t *) backtrace_alloc (state, ZDEBUG_TABLE_SIZE, |
| error_callback, data)); |
| if (zdebug_table == NULL) |
| return 0; |
| ret = elf_uncompress_zdebug (state, compressed, compressed_size, |
| zdebug_table, error_callback, data, |
| uncompressed, uncompressed_size); |
| backtrace_free (state, zdebug_table, ZDEBUG_TABLE_SIZE, |
| error_callback, data); |
| return ret; |
| } |
| |
| /* Number of LZMA states. */ |
| #define LZMA_STATES (12) |
| |
| /* Number of LZMA position states. The pb value of the property byte |
| is the number of bits to include in these states, and the maximum |
| value of pb is 4. */ |
| #define LZMA_POS_STATES (16) |
| |
| /* Number of LZMA distance states. These are used match distances |
| with a short match length: up to 4 bytes. */ |
| #define LZMA_DIST_STATES (4) |
| |
| /* Number of LZMA distance slots. LZMA uses six bits to encode larger |
| match lengths, so 1 << 6 possible probabilities. */ |
| #define LZMA_DIST_SLOTS (64) |
| |
| /* LZMA distances 0 to 3 are encoded directly, larger values use a |
| probability model. */ |
| #define LZMA_DIST_MODEL_START (4) |
| |
| /* The LZMA probability model ends at 14. */ |
| #define LZMA_DIST_MODEL_END (14) |
| |
| /* LZMA distance slots for distances less than 127. */ |
| #define LZMA_FULL_DISTANCES (128) |
| |
| /* LZMA uses four alignment bits. */ |
| #define LZMA_ALIGN_SIZE (16) |
| |
| /* LZMA match length is encoded with 4, 5, or 10 bits, some of which |
| are already known. */ |
| #define LZMA_LEN_LOW_SYMBOLS (8) |
| #define LZMA_LEN_MID_SYMBOLS (8) |
| #define LZMA_LEN_HIGH_SYMBOLS (256) |
| |
| /* LZMA literal encoding. */ |
| #define LZMA_LITERAL_CODERS_MAX (16) |
| #define LZMA_LITERAL_CODER_SIZE (0x300) |
| |
| /* LZMA is based on a large set of probabilities, each managed |
| independently. Each probability is an 11 bit number that we store |
| in a uint16_t. We use a single large array of probabilities. */ |
| |
| /* Lengths of entries in the LZMA probabilities array. The names used |
| here are copied from the Linux kernel implementation. */ |
| |
| #define LZMA_PROB_IS_MATCH_LEN (LZMA_STATES * LZMA_POS_STATES) |
| #define LZMA_PROB_IS_REP_LEN LZMA_STATES |
| #define LZMA_PROB_IS_REP0_LEN LZMA_STATES |
| #define LZMA_PROB_IS_REP1_LEN LZMA_STATES |
| #define LZMA_PROB_IS_REP2_LEN LZMA_STATES |
| #define LZMA_PROB_IS_REP0_LONG_LEN (LZMA_STATES * LZMA_POS_STATES) |
| #define LZMA_PROB_DIST_SLOT_LEN (LZMA_DIST_STATES * LZMA_DIST_SLOTS) |
| #define LZMA_PROB_DIST_SPECIAL_LEN (LZMA_FULL_DISTANCES - LZMA_DIST_MODEL_END) |
| #define LZMA_PROB_DIST_ALIGN_LEN LZMA_ALIGN_SIZE |
| #define LZMA_PROB_MATCH_LEN_CHOICE_LEN 1 |
| #define LZMA_PROB_MATCH_LEN_CHOICE2_LEN 1 |
| #define LZMA_PROB_MATCH_LEN_LOW_LEN (LZMA_POS_STATES * LZMA_LEN_LOW_SYMBOLS) |
| #define LZMA_PROB_MATCH_LEN_MID_LEN (LZMA_POS_STATES * LZMA_LEN_MID_SYMBOLS) |
| #define LZMA_PROB_MATCH_LEN_HIGH_LEN LZMA_LEN_HIGH_SYMBOLS |
| #define LZMA_PROB_REP_LEN_CHOICE_LEN 1 |
| #define LZMA_PROB_REP_LEN_CHOICE2_LEN 1 |
| #define LZMA_PROB_REP_LEN_LOW_LEN (LZMA_POS_STATES * LZMA_LEN_LOW_SYMBOLS) |
| #define LZMA_PROB_REP_LEN_MID_LEN (LZMA_POS_STATES * LZMA_LEN_MID_SYMBOLS) |
| #define LZMA_PROB_REP_LEN_HIGH_LEN LZMA_LEN_HIGH_SYMBOLS |
| #define LZMA_PROB_LITERAL_LEN \ |
| (LZMA_LITERAL_CODERS_MAX * LZMA_LITERAL_CODER_SIZE) |
| |
| /* Offsets into the LZMA probabilities array. This is mechanically |
| generated from the above lengths. */ |
| |
| #define LZMA_PROB_IS_MATCH_OFFSET 0 |
| #define LZMA_PROB_IS_REP_OFFSET \ |
| (LZMA_PROB_IS_MATCH_OFFSET + LZMA_PROB_IS_MATCH_LEN) |
| #define LZMA_PROB_IS_REP0_OFFSET \ |
| (LZMA_PROB_IS_REP_OFFSET + LZMA_PROB_IS_REP_LEN) |
| #define LZMA_PROB_IS_REP1_OFFSET \ |
| (LZMA_PROB_IS_REP0_OFFSET + LZMA_PROB_IS_REP0_LEN) |
| #define LZMA_PROB_IS_REP2_OFFSET \ |
| (LZMA_PROB_IS_REP1_OFFSET + LZMA_PROB_IS_REP1_LEN) |
| #define LZMA_PROB_IS_REP0_LONG_OFFSET \ |
| (LZMA_PROB_IS_REP2_OFFSET + LZMA_PROB_IS_REP2_LEN) |
| #define LZMA_PROB_DIST_SLOT_OFFSET \ |
| (LZMA_PROB_IS_REP0_LONG_OFFSET + LZMA_PROB_IS_REP0_LONG_LEN) |
| #define LZMA_PROB_DIST_SPECIAL_OFFSET \ |
| (LZMA_PROB_DIST_SLOT_OFFSET + LZMA_PROB_DIST_SLOT_LEN) |
| #define LZMA_PROB_DIST_ALIGN_OFFSET \ |
| (LZMA_PROB_DIST_SPECIAL_OFFSET + LZMA_PROB_DIST_SPECIAL_LEN) |
| #define LZMA_PROB_MATCH_LEN_CHOICE_OFFSET \ |
| (LZMA_PROB_DIST_ALIGN_OFFSET + LZMA_PROB_DIST_ALIGN_LEN) |
| #define LZMA_PROB_MATCH_LEN_CHOICE2_OFFSET \ |
| (LZMA_PROB_MATCH_LEN_CHOICE_OFFSET + LZMA_PROB_MATCH_LEN_CHOICE_LEN) |
| #define LZMA_PROB_MATCH_LEN_LOW_OFFSET \ |
| (LZMA_PROB_MATCH_LEN_CHOICE2_OFFSET + LZMA_PROB_MATCH_LEN_CHOICE2_LEN) |
| #define LZMA_PROB_MATCH_LEN_MID_OFFSET \ |
| (LZMA_PROB_MATCH_LEN_LOW_OFFSET + LZMA_PROB_MATCH_LEN_LOW_LEN) |
| #define LZMA_PROB_MATCH_LEN_HIGH_OFFSET \ |
| (LZMA_PROB_MATCH_LEN_MID_OFFSET + LZMA_PROB_MATCH_LEN_MID_LEN) |
| #define LZMA_PROB_REP_LEN_CHOICE_OFFSET \ |
| (LZMA_PROB_MATCH_LEN_HIGH_OFFSET + LZMA_PROB_MATCH_LEN_HIGH_LEN) |
| #define LZMA_PROB_REP_LEN_CHOICE2_OFFSET \ |
| (LZMA_PROB_REP_LEN_CHOICE_OFFSET + LZMA_PROB_REP_LEN_CHOICE_LEN) |
| #define LZMA_PROB_REP_LEN_LOW_OFFSET \ |
| (LZMA_PROB_REP_LEN_CHOICE2_OFFSET + LZMA_PROB_REP_LEN_CHOICE2_LEN) |
| #define LZMA_PROB_REP_LEN_MID_OFFSET \ |
| (LZMA_PROB_REP_LEN_LOW_OFFSET + LZMA_PROB_REP_LEN_LOW_LEN) |
| #define LZMA_PROB_REP_LEN_HIGH_OFFSET \ |
| (LZMA_PROB_REP_LEN_MID_OFFSET + LZMA_PROB_REP_LEN_MID_LEN) |
| #define LZMA_PROB_LITERAL_OFFSET \ |
| (LZMA_PROB_REP_LEN_HIGH_OFFSET + LZMA_PROB_REP_LEN_HIGH_LEN) |
| |
| #define LZMA_PROB_TOTAL_COUNT \ |
| (LZMA_PROB_LITERAL_OFFSET + LZMA_PROB_LITERAL_LEN) |
| |
| /* Check that the number of LZMA probabilities is the same as the |
| Linux kernel implementation. */ |
| |
| #if LZMA_PROB_TOTAL_COUNT != 1846 + (1 << 4) * 0x300 |
| #error Wrong number of LZMA probabilities |
| #endif |
| |
| /* Expressions for the offset in the LZMA probabilities array of a |
| specific probability. */ |
| |
| #define LZMA_IS_MATCH(state, pos) \ |
| (LZMA_PROB_IS_MATCH_OFFSET + (state) * LZMA_POS_STATES + (pos)) |
| #define LZMA_IS_REP(state) \ |
| (LZMA_PROB_IS_REP_OFFSET + (state)) |
| #define LZMA_IS_REP0(state) \ |
| (LZMA_PROB_IS_REP0_OFFSET + (state)) |
| #define LZMA_IS_REP1(state) \ |
| (LZMA_PROB_IS_REP1_OFFSET + (state)) |
| #define LZMA_IS_REP2(state) \ |
| (LZMA_PROB_IS_REP2_OFFSET + (state)) |
| #define LZMA_IS_REP0_LONG(state, pos) \ |
| (LZMA_PROB_IS_REP0_LONG_OFFSET + (state) * LZMA_POS_STATES + (pos)) |
| #define LZMA_DIST_SLOT(dist, slot) \ |
| (LZMA_PROB_DIST_SLOT_OFFSET + (dist) * LZMA_DIST_SLOTS + (slot)) |
| #define LZMA_DIST_SPECIAL(dist) \ |
| (LZMA_PROB_DIST_SPECIAL_OFFSET + (dist)) |
| #define LZMA_DIST_ALIGN(dist) \ |
| (LZMA_PROB_DIST_ALIGN_OFFSET + (dist)) |
| #define LZMA_MATCH_LEN_CHOICE \ |
| LZMA_PROB_MATCH_LEN_CHOICE_OFFSET |
| #define LZMA_MATCH_LEN_CHOICE2 \ |
| LZMA_PROB_MATCH_LEN_CHOICE2_OFFSET |
| #define LZMA_MATCH_LEN_LOW(pos, sym) \ |
| (LZMA_PROB_MATCH_LEN_LOW_OFFSET + (pos) * LZMA_LEN_LOW_SYMBOLS + (sym)) |
| #define LZMA_MATCH_LEN_MID(pos, sym) \ |
| (LZMA_PROB_MATCH_LEN_MID_OFFSET + (pos) * LZMA_LEN_MID_SYMBOLS + (sym)) |
| #define LZMA_MATCH_LEN_HIGH(sym) \ |
| (LZMA_PROB_MATCH_LEN_HIGH_OFFSET + (sym)) |
| #define LZMA_REP_LEN_CHOICE \ |
| LZMA_PROB_REP_LEN_CHOICE_OFFSET |
| #define LZMA_REP_LEN_CHOICE2 \ |
| LZMA_PROB_REP_LEN_CHOICE2_OFFSET |
| #define LZMA_REP_LEN_LOW(pos, sym) \ |
| (LZMA_PROB_REP_LEN_LOW_OFFSET + (pos) * LZMA_LEN_LOW_SYMBOLS + (sym)) |
| #define LZMA_REP_LEN_MID(pos, sym) \ |
| (LZMA_PROB_REP_LEN_MID_OFFSET + (pos) * LZMA_LEN_MID_SYMBOLS + (sym)) |
| #define LZMA_REP_LEN_HIGH(sym) \ |
| (LZMA_PROB_REP_LEN_HIGH_OFFSET + (sym)) |
| #define LZMA_LITERAL(code, size) \ |
| (LZMA_PROB_LITERAL_OFFSET + (code) * LZMA_LITERAL_CODER_SIZE + (size)) |
| |
| /* Read an LZMA varint from BUF, reading and updating *POFFSET, |
| setting *VAL. Returns 0 on error, 1 on success. */ |
| |
| static int |
| elf_lzma_varint (const unsigned char *compressed, size_t compressed_size, |
| size_t *poffset, uint64_t *val) |
| { |
| size_t off; |
| int i; |
| uint64_t v; |
| unsigned char b; |
| |
| off = *poffset; |
| i = 0; |
| v = 0; |
| while (1) |
| { |
| if (unlikely (off >= compressed_size)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| b = compressed[off]; |
| v |= (b & 0x7f) << (i * 7); |
| ++off; |
| if ((b & 0x80) == 0) |
| { |
| *poffset = off; |
| *val = v; |
| return 1; |
| } |
| ++i; |
| if (unlikely (i >= 9)) |
| { |
| elf_uncompress_failed (); |
| return 0; |
| } |
| } |
| } |
| |
| /* Normalize the LZMA range decoder, pulling in an extra input byte if |
| needed. */ |
| |
| static void |
| elf_lzma_range_normalize (const unsigned char *compressed, |
| size_t compressed_size, size_t *poffset, |
| uint32_t *prange, uint32_t *pcode) |
| { |
| if (*prange < (1U << 24)) |
| { |
| if (unlikely (*poffset >= compressed_size)) |
| { |
| /* We assume this will be caught elsewhere. */ |
| elf_uncompress_failed (); |
| return; |
| } |
| *prange <<= 8; |
| *pcode <<= 8; |
| *pcode += compressed[*poffset]; |
| ++*poffset; |
| } |
| } |
| |
| /* Read and return a single bit from the LZMA stream, reading and |
| updating *PROB. Each bit comes from the range coder. */ |
| |
| static int |
| elf_lzma_bit (const unsigned char *compressed, size_t compressed_size, |
| uint16_t *prob, size_t *poffset, uint32_t *prange, |
| uint32_t *pcode) |
| { |
| uint32_t bound; |
| |
| elf_lzma_range_normalize (compressed, compressed_size, poffset, |
| prange, pcode); |
| bound = (*prange >> 11) * (uint32_t) *prob; |
| if (*pcode < bound) |
| { |
| *prange = bound; |
| *prob += ((1U << 11) - *prob) >> 5; |
| return 0; |
| } |
| else |
| { |
| *prange -= bound; |
| *pcode -= bound; |
| *prob -= *prob >> 5; |
| return 1; |
| } |
| } |
| |
| /* Read an integer of size BITS from the LZMA stream, most significant |
| bit first. The bits are predicted using PROBS. */ |
| |
| static uint32_t |
| elf_lzma_integer (const unsigned char *compressed, size_t compressed_size, |
| uint16_t *probs, uint32_t bits, size_t *poffset, |
| uint32_t *prange, uint32_t *pcode) |
| { |
| uint32_t sym; |
| uint32_t i; |
| |
| sym = 1; |
| for (i = 0; i < bits; i++) |
| { |
| int bit; |
| |
| bit = elf_lzma_bit (compressed, compressed_size, probs + sym, poffset, |
| prange, pcode); |
| sym <<= 1; |
| sym += bit; |
| } |
| return sym - (1 << bits); |
| } |
| |
| /* Read an integer of size BITS from the LZMA stream, least |
| significant bit first. The bits are predicted using PROBS. */ |
| |
| static uint32_t |
| elf_lzma_reverse_integer (const unsigned char *compressed, |
| size_t compressed_size, uint16_t *probs, |
| uint32_t bits, size_t *poffset, uint32_t *prange, |
| uint32_t *pcode) |
| { |
| uint32_t sym; |
| uint32_t val; |
| uint32_t i; |
| |
| sym = 1; |
| val = 0; |
| for (i = 0; i < bits; i++) |
| { |
| int bit; |
| |
| bit = elf_lzma_bit (compressed, compressed_size, probs + sym, poffset, |
| prange, pcode); |
| sym <<= 1; |
| sym += bit; |
| val += bit << i; |
| } |
| return val; |
| } |
| |
| /* Read a length from the LZMA stream. IS_REP picks either LZMA_MATCH |
| or LZMA_REP probabilities. */ |
| |
| static uint32_t |
| elf_lzma_len (const unsigned char *compressed, size_t compressed_size, |
| uint16_t *probs, int is_rep, unsigned int pos_state, |
| size_t *poffset, uint32_t *prange, uint32_t *pcode) |
| { |
| uint16_t *probs_choice; |
| uint16_t *probs_sym; |
| uint32_t bits; |
| uint32_t len; |
| |
| probs_choice = probs + (is_rep |
| ? LZMA_REP_LEN_CHOICE |
| : LZMA_MATCH_LEN_CHOICE); |
| if (elf_lzma_bit (compressed, compressed_size, probs_choice, poffset, |
| prange, pcode)) |
| { |
| probs_choice = probs + (is_rep |
| ? LZMA_REP_LEN_CHOICE2 |
| : LZMA_MATCH_LEN_CHOICE2); |
| if (elf_lzma_bit (compressed, compressed_size, probs_choice, |
| poffset, prange, pcode)) |
| { |
| probs_sym = probs + (is_rep |
| ? LZMA_REP_LEN_HIGH (0) |
| : LZMA_MATCH_LEN_HIGH (0)); |
| bits = 8; |
| len = 2 + 8 + 8; |
| } |
| else |
| { |
| probs_sym = probs + (is_rep |
| ? LZMA_REP_LEN_MID (pos_state, 0) |
| : LZMA_MATCH_LEN_MID (pos_state, 0)); |
| bits = 3; |
| len = 2 + 8; |
| } |
| } |
| else |
| { |
| probs_sym = probs + (is_rep |
| ? LZMA_REP_LEN_LOW (pos_state, 0) |
| : LZMA_MATCH_LEN_LOW (pos_state, 0)); |
| bits = 3; |
| len = 2; |
| } |
| |
| |