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rockbox/utils/sbtools/elftosb.c
Amaury Pouly bdb8f4c15c sbtools: fix a few memcpy with overlapping src/dst, fix a parsing bug (would access one byte paste the end of the buffer) 
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29868 a1c6a512-1295-4272-9138-f99709370657
2011-05-13 12:20:49 +00:00

980 lines
29 KiB
C
Raw Blame History

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2011 Amaury Pouly
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#define _ISOC99_SOURCE
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <inttypes.h>
#include <string.h>
#include <ctype.h>
#include <time.h>
#include <stdarg.h>
#include "crypto.h"
#include "elf.h"
#include "sb.h"
#define bug(...) do { fprintf(stderr,"ERROR: "__VA_ARGS__); exit(1); } while(0)
#define bugp(a) do { perror("ERROR: "a); exit(1); } while(0)
bool g_debug = false;
#define ROUND_UP(val, round) ((((val) + (round) - 1) / (round)) * (round))
/**
* Misc
*/
void generate_random_data(void *buf, size_t sz)
{
static int rand_fd = -1;
if(rand_fd == -1)
rand_fd = open("/dev/urandom", O_RDONLY);
if(rand_fd == -1)
bugp("failed to open /dev/urandom");
if(read(rand_fd, buf, sz) != (ssize_t)sz)
bugp("failed to read /dev/urandom");
}
void *xmalloc(size_t s) /* malloc helper, used in elf.c */
{
void * r = malloc(s);
if(!r) bugp("malloc");
return r;
}
static int convxdigit(char digit, byte *val)
{
if(digit >= '0' && digit <= '9')
{
*val = digit - '0';
return 0;
}
else if(digit >= 'A' && digit <= 'F')
{
*val = digit - 'A' + 10;
return 0;
}
else if(digit >= 'a' && digit <= 'f')
{
*val = digit - 'a' + 10;
return 0;
}
else
return 1;
}
/**
* Key file parsing
*/
typedef byte (*key_array_t)[16];
int g_nr_keys;
key_array_t g_key_array;
static key_array_t read_keys(const char *key_file, int *num_keys)
{
int size;
struct stat st;
int fd = open(key_file,O_RDONLY);
if(fd == -1)
bugp("opening key file failed");
if(fstat(fd,&st) == -1)
bugp("key file stat() failed");
size = st.st_size;
char *buf = xmalloc(size);
if(read(fd, buf, size) != (ssize_t)size)
bugp("reading key file");
close(fd);
if(g_debug)
printf("Parsing key file '%s'...\n", key_file);
*num_keys = size ? 1 : 0;
char *ptr = buf;
/* allow trailing newline at the end (but no space after it) */
while(ptr != buf + size && (ptr + 1) != buf + size)
{
if(*ptr++ == '\n')
(*num_keys)++;
}
key_array_t keys = xmalloc(sizeof(byte[16]) * *num_keys);
int pos = 0;
for(int i = 0; i < *num_keys; i++)
{
/* skip ws */
while(pos < size && isspace(buf[pos]))
pos++;
/* enough space ? */
if((pos + 32) > size)
bugp("invalid key file");
for(int j = 0; j < 16; j++)
{
byte a, b;
if(convxdigit(buf[pos + 2 * j], &a) || convxdigit(buf[pos + 2 * j + 1], &b))
bugp(" invalid key, it should be a 128-bit key written in hexadecimal\n");
keys[i][j] = (a << 4) | b;
}
if(g_debug)
{
printf("Add key: ");
for(int j = 0; j < 16; j++)
printf("%02x", keys[i][j]);
printf("\n");
}
pos += 32;
}
free(buf);
return keys;
}
/**
* Command file parsing
*/
struct cmd_source_t
{
char *identifier;
char *filename;
struct cmd_source_t *next;
/* for later use */
bool elf_loaded;
struct elf_params_t elf;
};
enum cmd_inst_type_t
{
CMD_LOAD,
CMD_JUMP,
CMD_CALL
};
struct cmd_inst_t
{
enum cmd_inst_type_t type;
char *identifier;
struct cmd_inst_t *next;
};
struct cmd_section_t
{
uint32_t identifier;
struct cmd_inst_t *inst_list;
struct cmd_section_t *next;
};
struct cmd_file_t
{
struct cmd_source_t *source_list;
struct cmd_section_t *section_list;
};
enum lexem_type_t
{
LEX_IDENTIFIER,
LEX_LPAREN,
LEX_RPAREN,
LEX_NUMBER,
LEX_STRING, /* double-quoted string */
LEX_EQUAL,
LEX_SEMICOLON,
LEX_LBRACE,
LEX_RBRACE,
LEX_EOF
};
struct lexem_t
{
enum lexem_type_t type;
char *str;
uint32_t num;
};
static void __parse_string(char **ptr, char *end, void *user, void (*emit_fn)(void *user, char c))
{
while(*ptr != end)
{
if(**ptr == '"')
break;
else if(**ptr == '\\')
{
(*ptr)++;
if(*ptr == end)
bug("Unfinished string");
if(**ptr == '\\') emit_fn(user, '\\');
else if(**ptr == '\'') emit_fn(user, '\'');
else if(**ptr == '\"') emit_fn(user, '\"');
else bug("Unknown escape sequence \\%c", **ptr);
(*ptr)++;
}
else
emit_fn(user, *(*ptr)++);
}
if(*ptr == end || **ptr != '"')
bug("unfinished string");
(*ptr)++;
}
static void __parse_string_emit(void *user, char c)
{
char **pstr = (char **)user;
*(*pstr)++ = c;
}
static void __parse_string_count(void *user, char c)
{
(void) c;
(*(int *)user)++;
}
static void parse_string(char **ptr, char *end, struct lexem_t *lexem)
{
/* skip " */
(*ptr)++;
char *p = *ptr;
/* compute length */
int length = 0;
__parse_string(&p, end, (void *)&length, __parse_string_count);
/* parse again */
lexem->type = LEX_STRING;
lexem->str = xmalloc(length + 1);
lexem->str[length] = 0;
char *pstr = lexem->str;
__parse_string(ptr, end, (void *)&pstr, __parse_string_emit);
}
static void parse_number(char **ptr, char *end, struct lexem_t *lexem)
{
int base = 10;
if(**ptr == '0' && (*ptr) + 1 != end && (*ptr)[1] == 'x')
{
(*ptr) += 2;
base = 16;
}
lexem->type = LEX_NUMBER;
lexem->num = 0;
while(*ptr != end && isxdigit(**ptr))
{
if(base == 10 && !isdigit(**ptr))
break;
byte v;
if(convxdigit(**ptr, &v))
break;
lexem->num = base * lexem->num + v;
(*ptr)++;
}
}
static void parse_identifier(char **ptr, char *end, struct lexem_t *lexem)
{
/* remember position */
char *old = *ptr;
while(*ptr != end && (isalnum(**ptr) || **ptr == '_'))
(*ptr)++;
lexem->type = LEX_IDENTIFIER;
int len = *ptr - old;
lexem->str = xmalloc(len + 1);
lexem->str[len] = 0;
memcpy(lexem->str, old, len);
}
static void next_lexem(char **ptr, char *end, struct lexem_t *lexem)
{
#define ret_simple(t, advance) ({(*ptr) += advance; lexem->type = t; return;})
while(*ptr != end)
{
/* skip whitespace */
if(**ptr == ' ' || **ptr == '\t' || **ptr == '\n' || **ptr == '\r')
{
(*ptr)++;
continue;
}
/* skip comments */
if(**ptr == '/' && (*ptr) + 1 != end && (*ptr)[1] == '/')
{
while(*ptr != end && **ptr != '\n')
(*ptr)++;
continue;
}
break;
}
if(*ptr == end) ret_simple(LEX_EOF, 0);
if(**ptr == '(') ret_simple(LEX_LPAREN, 1);
if(**ptr == ')') ret_simple(LEX_RPAREN, 1);
if(**ptr == '{') ret_simple(LEX_LBRACE, 1);
if(**ptr == '}') ret_simple(LEX_RBRACE, 1);
if(**ptr == '=') ret_simple(LEX_EQUAL, 1);
if(**ptr == ';') ret_simple(LEX_SEMICOLON, 1);
if(**ptr == '"') return parse_string(ptr, end, lexem);
if(isdigit(**ptr)) return parse_number(ptr, end, lexem);
if(isalpha(**ptr) || **ptr == '_') return parse_identifier(ptr, end, lexem);
bug("Unexpected character '%c' in command file\n", **ptr);
#undef ret_simple
}
#if 0
static void log_lexem(struct lexem_t *lexem)
{
switch(lexem->type)
{
case LEX_EOF: printf("<eof>"); break;
case LEX_EQUAL: printf("="); break;
case LEX_IDENTIFIER: printf("id(%s)", lexem->str); break;
case LEX_LPAREN: printf("("); break;
case LEX_RPAREN: printf(")"); break;
case LEX_LBRACE: printf("{"); break;
case LEX_RBRACE: printf("}"); break;
case LEX_SEMICOLON: printf(";"); break;
case LEX_NUMBER: printf("num(%d)", lexem->num); break;
case LEX_STRING: printf("str(%s)", lexem->str); break;
default: printf("<unk>");
}
}
#endif
static struct cmd_source_t *find_source_by_id(struct cmd_file_t *cmd_file, const char *id)
{
struct cmd_source_t *src = cmd_file->source_list;
while(src)
{
if(strcmp(src->identifier, id) == 0)
return src;
src = src->next;
}
return NULL;
}
static struct cmd_file_t *read_command_file(const char *file)
{
int size;
struct stat st;
int fd = open(file,O_RDONLY);
if(fd == -1)
bugp("opening command file failed");
if(fstat(fd,&st) == -1)
bugp("command file stat() failed");
size = st.st_size;
char *buf = xmalloc(size);
if(read(fd, buf, size) != (ssize_t)size)
bugp("reading command file");
close(fd);
if(g_debug)
printf("Parsing command file '%s'...\n", file);
struct cmd_file_t *cmd_file = xmalloc(sizeof(struct cmd_file_t));
memset(cmd_file, 0, sizeof(struct cmd_file_t));
struct lexem_t lexem;
char *p = buf;
char *end = buf + size;
#define next() next_lexem(&p, end, &lexem)
/* sources */
next();
if(lexem.type != LEX_IDENTIFIER || strcmp(lexem.str, "sources") != 0)
bug("invalid command file: 'sources' expected");
next();
if(lexem.type != LEX_LBRACE)
bug("invalid command file: '{' expected after 'sources'");
while(true)
{
next();
if(lexem.type == LEX_RBRACE)
break;
struct cmd_source_t *src = xmalloc(sizeof(struct cmd_source_t));
memset(src, 0, sizeof(struct cmd_source_t));
src->next = cmd_file->source_list;
if(lexem.type != LEX_IDENTIFIER)
bug("invalid command file: identifier expected in sources");
src->identifier = lexem.str;
next();
if(lexem.type != LEX_EQUAL)
bug("invalid command file: '=' expected after identifier");
next();
if(lexem.type != LEX_STRING)
bug("invalid command file: string expected after '='");
src->filename = lexem.str;
next();
if(lexem.type != LEX_SEMICOLON)
bug("invalid command file: ';' expected after string");
if(find_source_by_id(cmd_file, src->identifier) != NULL)
bug("invalid command file: duplicated source identifier");
cmd_file->source_list = src;
}
/* sections */
struct cmd_section_t *end_sec = NULL;
while(true)
{
struct cmd_section_t *sec = xmalloc(sizeof(struct cmd_section_t));
struct cmd_inst_t *end_list = NULL;
memset(sec, 0, sizeof(struct cmd_section_t));
next();
if(lexem.type == LEX_EOF)
break;
if(lexem.type != LEX_IDENTIFIER || strcmp(lexem.str, "section") != 0)
bug("invalid command file: 'section' expected");
next();
if(lexem.type != LEX_LPAREN)
bug("invalid command file: '(' expected after 'section'");
next();
if(lexem.type != LEX_NUMBER)
bug("invalid command file: number expected as section identifier");
sec->identifier = lexem.num;
next();
if(lexem.type != LEX_RPAREN)
bug("invalid command file: ')' expected after section identifier");
next();
if(lexem.type != LEX_LBRACE)
bug("invalid command file: '{' expected after section directive");
/* commands */
while(true)
{
struct cmd_inst_t *inst = xmalloc(sizeof(struct cmd_inst_t));
memset(inst, 0, sizeof(struct cmd_inst_t));
next();
if(lexem.type == LEX_RBRACE)
break;
if(lexem.type != LEX_IDENTIFIER)
bug("invalid command file: instruction expected in section");
if(strcmp(lexem.str, "load") == 0)
inst->type = CMD_LOAD;
else if(strcmp(lexem.str, "call") == 0)
inst->type = CMD_CALL;
else if(strcmp(lexem.str, "jump") == 0)
inst->type = CMD_JUMP;
else
bug("invalid command file: instruction expected in section");
next();
if(lexem.type != LEX_IDENTIFIER)
bug("invalid command file: identifier expected after instruction");
inst->identifier = lexem.str;
if(find_source_by_id(cmd_file, inst->identifier) == NULL)
bug("invalid command file: undefined reference to source '%s'", inst->identifier);
next();
if(lexem.type != LEX_SEMICOLON)
bug("invalid command file: expected ';' after command");
if(end_list == NULL)
{
sec->inst_list = inst;
end_list = inst;
}
else
{
end_list->next = inst;
end_list = inst;
}
}
if(end_sec == NULL)
{
cmd_file->section_list = sec;
end_sec = sec;
}
else
{
end_sec->next = sec;
end_sec = sec;
}
}
#undef next
return cmd_file;
}
/**
* command file to sb conversion
*/
struct sb_inst_t
{
uint8_t inst; /* SB_INST_* */
uint32_t size;
// <union>
void *data;
uint32_t pattern;
uint32_t addr;
// </union>
/* for production use */
uint32_t padding_size;
uint8_t *padding;
};
struct sb_section_t
{
uint32_t identifier;
int nr_insts;
struct sb_inst_t *insts;
/* for production use */
uint32_t file_offset; /* in blocks */
uint32_t sec_size; /* in blocks */
};
struct sb_file_t
{
int nr_sections;
struct sb_section_t *sections;
/* for production use */
uint32_t image_size; /* in blocks */
};
static bool elf_read(void *user, uint32_t addr, void *buf, size_t count)
{
if(lseek(*(int *)user, addr, SEEK_SET) == (off_t)-1)
return false;
return read(*(int *)user, buf, count) == (ssize_t)count;
}
static void elf_printf(void *user, bool error, const char *fmt, ...)
{
if(!g_debug && !error)
return;
(void) user;
va_list args;
va_start(args, fmt);
vprintf(fmt, args);
va_end(args);
}
static void load_elf_by_id(struct cmd_file_t *cmd_file, const char *id)
{
struct cmd_source_t *src = find_source_by_id(cmd_file, id);
if(src == NULL)
bug("undefined reference to source '%s'\n", id);
/* avoid reloading */
if(src->elf_loaded)
return;
int fd = open(src->filename, O_RDONLY);
if(fd < 0)
bug("cannot open '%s' (id '%s')\n", src->filename, id);
if(g_debug)
printf("Loading ELF file '%s'...\n", src->filename);
elf_init(&src->elf);
src->elf_loaded = elf_read_file(&src->elf, elf_read, elf_printf, &fd);
close(fd);
if(!src->elf_loaded)
bug("error loading elf file '%s' (id '%s')\n", src->filename, id);
}
static struct sb_file_t *apply_cmd_file(struct cmd_file_t *cmd_file)
{
struct sb_file_t *sb = xmalloc(sizeof(struct sb_file_t));
memset(sb, 0, sizeof(struct sb_file_t));
if(g_debug)
printf("Applying command file...\n");
/* count sections */
struct cmd_section_t *csec = cmd_file->section_list;
while(csec)
{
sb->nr_sections++;
csec = csec->next;
}
sb->sections = xmalloc(sb->nr_sections * sizeof(struct sb_section_t));
memset(sb->sections, 0, sb->nr_sections * sizeof(struct sb_section_t));
/* flatten sections */
csec = cmd_file->section_list;
for(int i = 0; i < sb->nr_sections; i++, csec = csec->next)
{
struct sb_section_t *sec = &sb->sections[i];
sec->identifier = csec->identifier;
/* count instructions */
struct cmd_inst_t *cinst = csec->inst_list;
while(cinst)
{
load_elf_by_id(cmd_file, cinst->identifier);
struct elf_params_t *elf = &find_source_by_id(cmd_file, cinst->identifier)->elf;
if(cinst->type == CMD_LOAD)
sec->nr_insts += elf_get_nr_sections(elf);
else if(cinst->type == CMD_JUMP || cinst->type == CMD_CALL)
{
if(!elf_get_start_addr(elf, NULL))
bug("cannot jump/call '%s' because it has no starting point !\n", cinst->identifier);
sec->nr_insts++;
}
cinst = cinst->next;
}
sec->insts = xmalloc(sec->nr_insts * sizeof(struct sb_inst_t));
memset(sec->insts, 0, sec->nr_insts * sizeof(struct sb_inst_t));
/* flatten */
int idx = 0;
cinst = csec->inst_list;
while(cinst)
{
struct elf_params_t *elf = &find_source_by_id(cmd_file, cinst->identifier)->elf;
if(cinst->type == CMD_LOAD)
{
struct elf_section_t *esec = elf->first_section;
while(esec)
{
if(esec->type == EST_LOAD)
{
sec->insts[idx].inst = SB_INST_LOAD;
sec->insts[idx].addr = esec->addr;
sec->insts[idx].size = esec->size;
sec->insts[idx++].data = esec->section;
}
else if(esec->type == EST_FILL)
{
sec->insts[idx].inst = SB_INST_FILL;
sec->insts[idx].addr = esec->addr;
sec->insts[idx].size = esec->size;
sec->insts[idx++].pattern = esec->pattern;
}
esec = esec->next;
}
}
else if(cinst->type == CMD_JUMP || cinst->type == CMD_CALL)
{
sec->insts[idx].inst = (cinst->type == CMD_JUMP) ? SB_INST_JUMP : SB_INST_CALL;
sec->insts[idx++].addr = elf->start_addr;
}
cinst = cinst->next;
}
}
return sb;
}
/**
* Sb file production
*/
static void fill_gaps(struct sb_file_t *sb)
{
for(int i = 0; i < sb->nr_sections; i++)
{
struct sb_section_t *sec = &sb->sections[i];
for(int j = 0; j < sec->nr_insts; j++)
{
struct sb_inst_t *inst = &sec->insts[j];
if(inst->inst != SB_INST_LOAD)
continue;
inst->padding_size = ROUND_UP(inst->size, BLOCK_SIZE) - inst->size;
/* emulate elftosb2 behaviour: generate 15 bytes (that's a safe maximum) */
inst->padding = xmalloc(15);
generate_random_data(inst->padding, 15);
}
}
}
static void compute_sb_offsets(struct sb_file_t *sb)
{
sb->image_size = 0;
/* sb header */
sb->image_size += sizeof(struct sb_header_t) / BLOCK_SIZE;
/* sections headers */
sb->image_size += sb->nr_sections * sizeof(struct sb_section_header_t) / BLOCK_SIZE;
/* key dictionary */
sb->image_size += g_nr_keys * sizeof(struct sb_key_dictionary_entry_t) / BLOCK_SIZE;
/* sections */
for(int i = 0; i < sb->nr_sections; i++)
{
/* each section has a preliminary TAG command */
sb->image_size += sizeof(struct sb_instruction_tag_t) / BLOCK_SIZE;
struct sb_section_t *sec = &sb->sections[i];
sec->file_offset = sb->image_size;
for(int j = 0; j < sec->nr_insts; j++)
{
struct sb_inst_t *inst = &sec->insts[j];
if(inst->inst == SB_INST_CALL || inst->inst == SB_INST_JUMP)
{
if(g_debug)
printf("%s | addr=0x%08x | arg=0x%08x\n",
inst->inst == SB_INST_CALL ? "CALL" : "JUMP", inst->addr, 0);
sb->image_size += sizeof(struct sb_instruction_call_t) / BLOCK_SIZE;
sec->sec_size += sizeof(struct sb_instruction_call_t) / BLOCK_SIZE;
}
else if(inst->inst == SB_INST_FILL)
{
if(g_debug)
printf("FILL | addr=0x%08x | len=0x%08x | pattern=0x%08x\n",
inst->addr, inst->size, inst->pattern);
sb->image_size += sizeof(struct sb_instruction_fill_t) / BLOCK_SIZE;
sec->sec_size += sizeof(struct sb_instruction_fill_t) / BLOCK_SIZE;
}
else if(inst->inst == SB_INST_LOAD)
{
if(g_debug)
printf("LOAD | addr=0x%08x | len=0x%08x\n", inst->addr, inst->size);
/* load header */
sb->image_size += sizeof(struct sb_instruction_load_t) / BLOCK_SIZE;
sec->sec_size += sizeof(struct sb_instruction_load_t) / BLOCK_SIZE;
/* data + alignment */
sb->image_size += (inst->size + inst->padding_size) / BLOCK_SIZE;
sec->sec_size += (inst->size + inst->padding_size) / BLOCK_SIZE;
}
}
}
/* final signature */
sb->image_size += 2;
}
static uint64_t generate_timestamp()
{
struct tm tm_base = {0, 0, 0, 1, 0, 100, 0, 0, 1, 0, NULL}; /* 2000/1/1 0:00:00 */
time_t t = time(NULL) - mktime(&tm_base);
return (uint64_t)t * 1000000L;
}
void generate_version(struct sb_version_t *ver)
{
ver->major = 0x999;
ver->pad0 = 0;
ver->minor = 0x999;
ver->pad1 = 0;
ver->revision = 0x999;
ver->pad2 = 0;
}
static void produce_sb_header(struct sb_file_t *sb, struct sb_header_t *sb_hdr)
{
struct sha_1_params_t sha_1_params;
sb_hdr->signature[0] = 'S';
sb_hdr->signature[1] = 'T';
sb_hdr->signature[2] = 'M';
sb_hdr->signature[3] = 'P';
sb_hdr->major_ver = IMAGE_MAJOR_VERSION;
sb_hdr->minor_ver = IMAGE_MINOR_VERSION;
sb_hdr->flags = 0;
sb_hdr->image_size = sb->image_size;
sb_hdr->header_size = sizeof(struct sb_header_t) / BLOCK_SIZE;
sb_hdr->first_boot_sec_id = sb->sections[0].identifier;
sb_hdr->nr_keys = g_nr_keys;
sb_hdr->nr_sections = sb->nr_sections;
sb_hdr->sec_hdr_size = sizeof(struct sb_section_header_t) / BLOCK_SIZE;
sb_hdr->key_dict_off = sb_hdr->header_size +
sb_hdr->sec_hdr_size * sb_hdr->nr_sections;
sb_hdr->first_boot_tag_off = sb_hdr->key_dict_off +
sizeof(struct sb_key_dictionary_entry_t) * sb_hdr->nr_keys / BLOCK_SIZE;
generate_random_data(sb_hdr->rand_pad0, sizeof(sb_hdr->rand_pad0));
generate_random_data(sb_hdr->rand_pad1, sizeof(sb_hdr->rand_pad1));
sb_hdr->timestamp = generate_timestamp();
generate_version(&sb_hdr->product_ver);
generate_version(&sb_hdr->component_ver);
sb_hdr->drive_tag = 0;
sha_1_init(&sha_1_params);
sha_1_update(&sha_1_params, &sb_hdr->signature[0],
sizeof(struct sb_header_t) - sizeof(sb_hdr->sha1_header));
sha_1_finish(&sha_1_params);
sha_1_output(&sha_1_params, sb_hdr->sha1_header);
}
static void produce_sb_section_header(struct sb_section_t *sec,
struct sb_section_header_t *sec_hdr)
{
sec_hdr->identifier = sec->identifier;
sec_hdr->offset = sec->file_offset;
sec_hdr->size = sec->sec_size;
sec_hdr->flags = SECTION_BOOTABLE;
}
static uint8_t instruction_checksum(struct sb_instruction_header_t *hdr)
{
uint8_t sum = 90;
byte *ptr = (byte *)hdr;
for(int i = 1; i < 16; i++)
sum += ptr[i];
return sum;
}
static void produce_section_tag_cmd(struct sb_section_t *sec,
struct sb_instruction_tag_t *tag, bool is_last)
{
tag->hdr.opcode = SB_INST_TAG;
tag->hdr.flags = is_last ? SB_INST_LAST_TAG : 0;
tag->identifier = sec->identifier;
tag->len = sec->sec_size;
tag->flags = SECTION_BOOTABLE;
tag->hdr.checksum = instruction_checksum(&tag->hdr);
}
void produce_sb_instruction(struct sb_inst_t *inst,
struct sb_instruction_common_t *cmd)
{
cmd->hdr.flags = 0;
cmd->hdr.opcode = inst->inst;
cmd->addr = inst->addr;
cmd->len = inst->size;
switch(inst->inst)
{
case SB_INST_CALL:
case SB_INST_JUMP:
cmd->len = 0;
cmd->data = 0;
break;
case SB_INST_FILL:
cmd->data = inst->pattern;
break;
case SB_INST_LOAD:
cmd->data = crc_continue(crc(inst->data, inst->size),
inst->padding, inst->padding_size);
break;
default:
break;
}
cmd->hdr.checksum = instruction_checksum(&cmd->hdr);
}
static void produce_sb_file(struct sb_file_t *sb, const char *filename)
{
int fd = open(filename, O_WRONLY | O_TRUNC | O_CREAT,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
if(fd < 0)
bugp("cannot open output file");
byte real_key[16];
byte (*cbc_macs)[16] = xmalloc(16 * g_nr_keys);
/* init CBC-MACs */
for(int i = 0; i < g_nr_keys; i++)
memset(cbc_macs[i], 0, 16);
fill_gaps(sb);
compute_sb_offsets(sb);
generate_random_data(real_key, sizeof(real_key));
/* global SHA-1 */
struct sha_1_params_t file_sha1;
sha_1_init(&file_sha1);
/* produce and write header */
struct sb_header_t sb_hdr;
produce_sb_header(sb, &sb_hdr);
sha_1_update(&file_sha1, (byte *)&sb_hdr, sizeof(sb_hdr));
write(fd, &sb_hdr, sizeof(sb_hdr));
/* update CBC-MACs */
for(int i = 0; i < g_nr_keys; i++)
cbc_mac((byte *)&sb_hdr, NULL, sizeof(sb_hdr) / BLOCK_SIZE, g_key_array[i],
cbc_macs[i], &cbc_macs[i], 1);
/* produce and write section headers */
for(int i = 0; i < sb_hdr.nr_sections; i++)
{
struct sb_section_header_t sb_sec_hdr;
produce_sb_section_header(&sb->sections[i], &sb_sec_hdr);
sha_1_update(&file_sha1, (byte *)&sb_sec_hdr, sizeof(sb_sec_hdr));
write(fd, &sb_sec_hdr, sizeof(sb_sec_hdr));
/* update CBC-MACs */
for(int j = 0; j < g_nr_keys; j++)
cbc_mac((byte *)&sb_sec_hdr, NULL, sizeof(sb_sec_hdr) / BLOCK_SIZE,
g_key_array[j], cbc_macs[j], &cbc_macs[j], 1);
}
/* produce key dictionary */
for(int i = 0; i < g_nr_keys; i++)
{
struct sb_key_dictionary_entry_t entry;
memcpy(entry.hdr_cbc_mac, cbc_macs[i], 16);
cbc_mac(real_key, entry.key, sizeof(real_key) / BLOCK_SIZE, g_key_array[i],
(byte *)&sb_hdr, NULL, 1);
write(fd, &entry, sizeof(entry));
sha_1_update(&file_sha1, (byte *)&entry, sizeof(entry));
}
/* produce sections data */
for(int i = 0; i< sb_hdr.nr_sections; i++)
{
/* produce tag command */
struct sb_instruction_tag_t tag_cmd;
produce_section_tag_cmd(&sb->sections[i], &tag_cmd, (i + 1) == sb_hdr.nr_sections);
if(g_nr_keys > 0)
cbc_mac((byte *)&tag_cmd, (byte *)&tag_cmd, sizeof(tag_cmd) / BLOCK_SIZE,
real_key, (byte *)&sb_hdr, NULL, 1);
sha_1_update(&file_sha1, (byte *)&tag_cmd, sizeof(tag_cmd));
write(fd, &tag_cmd, sizeof(tag_cmd));
/* produce other commands */
byte cur_cbc_mac[16];
memcpy(cur_cbc_mac, (byte *)&sb_hdr, 16);
for(int j = 0; j < sb->sections[i].nr_insts; j++)
{
struct sb_inst_t *inst = &sb->sections[i].insts[j];
/* command */
struct sb_instruction_common_t cmd;
produce_sb_instruction(inst, &cmd);
if(g_nr_keys > 0)
cbc_mac((byte *)&cmd, (byte *)&cmd, sizeof(cmd) / BLOCK_SIZE,
real_key, cur_cbc_mac, &cur_cbc_mac, 1);
sha_1_update(&file_sha1, (byte *)&cmd, sizeof(cmd));
write(fd, &cmd, sizeof(cmd));
/* data */
if(inst->inst == SB_INST_LOAD)
{
uint32_t sz = inst->size + inst->padding_size;
byte *data = xmalloc(sz);
memcpy(data, inst->data, inst->size);
memcpy(data + inst->size, inst->padding, inst->padding_size);
if(g_nr_keys > 0)
cbc_mac(data, data, sz / BLOCK_SIZE,
real_key, cur_cbc_mac, &cur_cbc_mac, 1);
sha_1_update(&file_sha1, data, sz);
write(fd, data, sz);
free(data);
}
}
}
/* write file SHA-1 */
byte final_sig[32];
sha_1_finish(&file_sha1);
sha_1_output(&file_sha1, final_sig);
generate_random_data(final_sig + 20, 12);
if(g_nr_keys > 0)
cbc_mac(final_sig, final_sig, 2, real_key, (byte *)&sb_hdr, NULL, 1);
write(fd, final_sig, 32);
close(fd);
}
int main(int argc, const char **argv)
{
if(argc != 4)
{
printf("Usage: %s <cmd file> <key file> <out file>\n",*argv);
printf("To enable debug mode, set environement variable SB_DEBUG to YES\n");
return 1;
}
if(getenv("SB_DEBUG") != NULL && strcmp(getenv("SB_DEBUG"), "YES") == 0)
g_debug = true;
g_key_array = read_keys(argv[2], &g_nr_keys);
struct cmd_file_t *cmd_file = read_command_file(argv[1]);
struct sb_file_t *sb_file = apply_cmd_file(cmd_file);
produce_sb_file(sb_file, argv[3]);
return 0;
}
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