struct sr_operating_system *
sr_operating_system_new()
{
struct sr_operating_system *operating_system = sr_malloc(sizeof(struct sr_operating_system));
sr_operating_system_init(operating_system);
return operating_system;
}
struct sr_core_stacktrace *
sr_core_stacktrace_new()
{
struct sr_core_stacktrace *stacktrace =
sr_malloc(sizeof(struct sr_core_stacktrace));
sr_core_stacktrace_init(stacktrace);
return stacktrace;
}
struct sr_ruby_frame *
sr_ruby_frame_new()
{
struct sr_ruby_frame *frame =
sr_malloc(sizeof(struct sr_ruby_frame));
sr_ruby_frame_init(frame);
return frame;
}
struct sr_java_frame *
sr_java_frame_new_exception()
{
struct sr_java_frame *frame =
sr_malloc(sizeof(*frame));
sr_java_frame_init(frame);
frame->is_exception = true;
return frame;
}
char *
sr_disasm_binary_to_text(struct sr_disasm_state *state,
uint64_t start_offset,
uint64_t size,
char **error_message)
{
#if HAVE_LIBOPCODES
asection *section = state->info.section;
if (start_offset < section->vma
|| (start_offset + size) > section->vma + section->size)
{
*error_message = sr_asprintf(
"Invalid function range: 0x%"PRIx64" - 0x%"PRIx64,
start_offset,
start_offset + size);
return NULL;
}
char *code = sr_malloc(size);
bool success = bfd_get_section_contents(state->bfd_file,
state->info.section,
code,
start_offset - section->vma,
size);
if (!success)
{
*error_message = sr_strdup("Failed to get section contents.");
return NULL;
}
struct sr_strbuf *strbuf = sr_strbuf_new();
for (int i = 0; i < size; ++i)
{
sr_strbuf_append_strf(strbuf, "0x%02x ", (unsigned)code[i]);
if ((i + 1) % 12 == 0)
sr_strbuf_append_char(strbuf, '\n');
}
free(code);
return sr_strbuf_free_nobuf(strbuf);
#else // HAVE_LIBOPCODES
*error_message = sr_asprintf("satyr compiled without libopcodes");
return NULL;
#endif // HAVE_LIBOPCODES
}
struct sr_distances *
sr_distances_new(int m, int n)
{
struct sr_distances *distances = sr_malloc(sizeof(struct sr_distances));
/* The number of rows has to be smaller than columns. */
if (m >= n)
m = n - 1;
assert(m > 0 && n > 1 && m < n);
distances->m = m;
distances->n = n;
distances->distances = sr_malloc_array(
get_distance_position(distances, m - 1, n - 1) + 1,
sizeof(*distances->distances)
);
return distances;
}
int so_scheduler_add(soscheduler *s , void *db)
{
sr_mutexlock(&s->lock);
so *e = s->env;
int count = s->count + 1;
void **i = sr_malloc(&e->a, count * sizeof(void*));
if (srunlikely(i == NULL)) {
sr_mutexunlock(&s->lock);
return -1;
}
memcpy(i, s->i, s->count * sizeof(void*));
i[s->count] = db;
void *iprev = s->i;
s->i = i;
s->count = count;
sr_mutexunlock(&s->lock);
if (iprev)
sr_free(&e->a, iprev);
return 0;
}
int so_scheduler_del(soscheduler *s, void *db)
{
if (srunlikely(s->i == NULL))
return 0;
sr_mutexlock(&s->lock);
so *e = s->env;
int count = s->count - 1;
if (srunlikely(count == 0)) {
s->count = 0;
sr_free(&e->a, s->i);
s->i = NULL;
sr_mutexunlock(&s->lock);
return 0;
}
void **i = sr_malloc(&e->a, count * sizeof(void*));
if (srunlikely(i == NULL)) {
sr_mutexunlock(&s->lock);
return -1;
}
int j = 0;
int k = 0;
while (j < s->count) {
if (s->i[j] == db) {
j++;
continue;
}
i[k] = s->i[j];
k++;
j++;
}
void *iprev = s->i;
s->i = i;
s->count = count;
if (srunlikely(s->rr >= s->count))
s->rr = 0;
sr_mutexunlock(&s->lock);
sr_free(&e->a, iprev);
return 0;
}
sinode *si_nodenew(sr *r)
{
sinode *n = (sinode*)sr_malloc(r->a, sizeof(sinode));
if (srunlikely(n == NULL)) {
sr_malfunction(r->e, "%s", "memory allocation failed");
return NULL;
}
n->recover = 0;
n->backup = 0;
n->flags = 0;
n->update_time = 0;
n->used = 0;
si_branchinit(&n->self);
n->branch = NULL;
n->branch_count = 0;
sr_fileinit(&n->file, r->a);
sv_indexinit(&n->i0);
sv_indexinit(&n->i1);
sr_rbinitnode(&n->node);
sr_rqinitnode(&n->nodecompact);
sr_rqinitnode(&n->nodebranch);
sr_listinit(&n->commit);
return n;
}
struct sr_elf_fde *
sr_elf_get_eh_frame(const char *filename,
char **error_message)
{
#ifdef WITH_ELFUTILS
/* Open the input file. */
int fd = open(filename, O_RDONLY);
if (fd < 0)
{
*error_message = sr_asprintf("Failed to open file %s: %s",
filename,
strerror(errno));
return NULL;
}
/* Initialize libelf on the opened file. */
Elf *elf = elf_begin(fd, ELF_C_READ, NULL);
if (!elf)
{
*error_message = sr_asprintf("Failed to run elf_begin on file %s: %s",
filename,
elf_errmsg(-1));
close(fd);
return NULL;
}
unsigned char *e_ident = (unsigned char *)elf_getident(elf, NULL);
if (!e_ident)
{
*error_message = sr_asprintf("elf_getident failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
/* Look up the .eh_frame section */
GElf_Shdr shdr;
Elf_Data *section_data;
char *find_section_error_message;
if (!find_elf_section_by_name(elf,
".eh_frame",
§ion_data,
&shdr,
&find_section_error_message))
{
*error_message = sr_asprintf("Failed to find .eh_frame section for %s: %s",
filename,
find_section_error_message);
free(find_section_error_message);
elf_end(elf);
close(fd);
return NULL;
}
/* Get the address at which the executable segment is loaded. If
* the .eh_frame addresses are absolute, this is used to convert
* them to relative to the beginning of executable segment. We
* are looking for the first LOAD segment that is executable, I
* hope this is sufficient.
*/
size_t phnum;
if (elf_getphdrnum(elf, &phnum) != 0)
{
*error_message = sr_asprintf("elf_getphdrnum failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
uint64_t exec_base = -1;
int i;
for (i = 0; i < phnum; i++)
{
GElf_Phdr phdr;
if (gelf_getphdr(elf, i, &phdr) != &phdr)
{
*error_message = sr_asprintf("gelf_getphdr failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
if (phdr.p_type == PT_LOAD && phdr.p_flags & PF_X)
{
exec_base = phdr.p_vaddr;
break;
}
}
if (-1 == exec_base)
{
*error_message = sr_asprintf("Can't determine executable base for %s",
filename);
elf_end(elf);
close(fd);
return NULL;
}
/* We now have a handle to .eh_frame data. We'll use
* dwarf_next_cfi to iterate through all FDEs looking for those
* matching the addresses we have.
*
* Some info on .eh_frame can be found at
* http://www.airs.com/blog/archives/460 and in DWARF
* documentation for .debug_frame. The initial_location and
* address_range decoding is 'inspired' by elfutils source.
*
* @todo If this linear scan is too slow, we can do binary search
* on .eh_frame_hdr -- see http://www.airs.com/blog/archives/462
*/
struct sr_elf_fde *result = NULL, *last = NULL;
struct cie *cie_list = NULL, *cie_list_last = NULL;
Dwarf_Off cfi_offset_next = 0;
while (true)
{
Dwarf_CFI_Entry cfi;
Dwarf_Off cfi_offset = cfi_offset_next;
int ret = dwarf_next_cfi(e_ident,
section_data,
1,
cfi_offset,
&cfi_offset_next,
&cfi);
if (ret > 0)
{
/* We're at the end. */
break;
}
if (ret < 0)
{
/* Error. If cfi_offset_next was updated, we may skip the
* erroneous cfi. */
if (cfi_offset_next > cfi_offset)
continue;
*error_message = sr_asprintf("dwarf_next_cfi failed for %s: %s",
filename,
dwarf_errmsg(-1));
cie_free(cie_list);
sr_elf_eh_frame_free(result);
elf_end(elf);
close(fd);
return NULL;
}
if (dwarf_cfi_cie_p(&cfi))
{
/* Current CFI is a CIE. We store its offset and FDE encoding
* attributes to be used when reading FDEs.
*/
/* Default FDE encoding (i.e. no R in augmentation string) is
* DW_EH_PE_absptr.
*/
char *cie_error_message;
struct cie *cie = read_cie(&cfi,
cfi_offset,
e_ident,
&cie_error_message);
if (!cie)
{
*error_message = sr_asprintf("CIE reading failed for %s: %s",
filename,
cie_error_message);
free(cie_error_message);
cie_free(cie_list);
sr_elf_eh_frame_free(result);
elf_end(elf);
close(fd);
return NULL;
}
/* Append the newly parsed CIE to our list of CIEs. */
if (cie_list)
{
cie_list_last->next = cie;
cie_list_last = cie;
}
else
cie_list = cie_list_last = cie;
}
else
{
/* Current CFI is an FDE.
*/
struct cie *cie = cie_list;
/* Find the CIE data that we should have saved earlier. */
while (cie)
{
/* In .eh_frame, CIE_pointer is relative, but libdw converts it
* to absolute offset. */
if (cfi.fde.CIE_pointer == cie->cie_offset)
break; /* Found. */
cie = cie->next;
}
if (!cie)
{
*error_message = sr_asprintf("CIE not found for FDE %jx in %s",
(uintmax_t)cfi_offset,
filename);
cie_free(cie_list);
sr_elf_eh_frame_free(result);
elf_end(elf);
close(fd);
return NULL;
}
/* Read the two numbers we need and if they are PC-relative,
* compute the offset from VMA base
*/
uint64_t initial_location = fde_read_address(cfi.fde.start,
cie->ptr_len);
uint64_t address_range = fde_read_address(cfi.fde.start + cie->ptr_len,
cie->ptr_len);
if (cie->pcrel)
{
/* We need to determine how long is the 'length' (and
* consequently CIE id) field of this FDE -- it can be
* either 4 or 12 bytes long. */
uint64_t length = fde_read_address(section_data->d_buf + cfi_offset, 4);
uint64_t skip = (length == 0xffffffffUL ? 12 : 4);
uint64_t mask = (cie->ptr_len == 4 ? 0xffffffffUL : 0xffffffffffffffffUL);
initial_location += shdr.sh_offset + cfi_offset + 2 * skip;
initial_location &= mask;
}
else
{
/* Assuming that not pcrel means absolute address
* (what if the file is a library?). Convert to
* text-section-start-relative.
*/
initial_location -= exec_base;
}
struct sr_elf_fde *fde = sr_malloc(sizeof(struct sr_elf_fde));
fde->exec_base = exec_base;
fde->start_address = initial_location;
fde->length = address_range;
fde->next = NULL;
/* Append the newly parsed Frame Description Entry to our
* list of FDEs.
*/
if (result)
{
last->next = fde;
last = fde;
}
else
result = last = fde;
}
}
cie_free(cie_list);
elf_end(elf);
close(fd);
return result;
#else /* WITH_ELFUTILS */
*error_message = sr_asprintf("satyr compiled without elfutils");
return NULL;
#endif /* WITH_ELFUTILS */
}
struct sr_elf_plt_entry *
sr_elf_get_procedure_linkage_table(const char *filename,
char **error_message)
{
#ifdef WITH_ELFUTILS
/* Open the input file. */
int fd = open(filename, O_RDONLY);
if (fd < 0)
{
*error_message = sr_asprintf("Failed to open file %s: %s",
filename,
strerror(errno));
return NULL;
}
/* Initialize libelf on the opened file. */
Elf *elf = elf_begin(fd, ELF_C_READ, NULL);
if (!elf)
{
*error_message = sr_asprintf("Failed to run elf_begin on file %s: %s",
filename,
elf_errmsg(-1));
close(fd);
return NULL;
}
/* Find the .plt section. */
GElf_Shdr shdr;
Elf_Data *plt_data;
char *find_section_error_message;
size_t plt_section_index = find_elf_section_by_name(elf,
".plt",
&plt_data,
&shdr,
&find_section_error_message);
if (0 == plt_section_index)
{
*error_message = sr_asprintf("Failed to find .plt section for %s: %s",
filename,
find_section_error_message);
free(find_section_error_message);
elf_end(elf);
close(fd);
return NULL;
}
/* Find the relocation section for .plt (typically .rela.plt), together
* with its symbol and string table
*/
uint64_t plt_base = shdr.sh_addr;
Elf_Data *rela_plt_data = NULL;
Elf_Data *plt_symbols = NULL;
size_t stringtable = 0;
Elf_Scn *section = NULL;
while ((section = elf_nextscn(elf, section)) != NULL)
{
if (gelf_getshdr(section, &shdr) != &shdr)
{
*error_message = sr_asprintf("gelf_getshdr failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
if (shdr.sh_type == SHT_RELA &&
shdr.sh_info == plt_section_index)
{
rela_plt_data = elf_getdata(section, NULL);
if (!rela_plt_data)
{
*error_message = sr_asprintf("elf_getdata failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
/* Get symbol section for .rela.plt */
Elf_Scn *symbol_section = elf_getscn(elf, shdr.sh_link);
if (!symbol_section)
{
*error_message = sr_asprintf("elf_getscn failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
plt_symbols = elf_getdata(symbol_section, NULL);
if (!plt_symbols)
{
*error_message = sr_asprintf("elf_getdata failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
/* Get string table for the symbol table. */
if (gelf_getshdr(symbol_section, &shdr) != &shdr)
{
*error_message = sr_asprintf("gelf_getshdr failed for %s: %s",
filename,
elf_errmsg(-1));
elf_end(elf);
close(fd);
return NULL;
}
stringtable = shdr.sh_link;
break;
}
}
if (0 == stringtable)
{
*error_message = sr_asprintf("Unable to read symbol table for .plt for file %s",
filename);
elf_end(elf);
close(fd);
return NULL;
}
/* PLT looks like this (see also AMD64 ABI, page 78):
*
* Disassembly of section .plt:
*
* 0000003463e01010 <attr_removef@plt-0x10>:
* 3463e01010: ff 35 2a 2c 20 00 pushq 0x202c2a(%rip) <-- here is plt_base
* 3463e01016: ff 25 2c 2c 20 00 jmpq *0x202c2c(%rip) each "slot" is 16B wide
* 3463e0101c: 0f 1f 40 00 nopl 0x0(%rax) 0-th slot is skipped
*
* 0000003463e01020 <attr_removef@plt>:
* 3463e01020: ff 25 2a 2c 20 00 jmpq *0x202c2a(%rip)
* 3463e01026: 68 00 00 00 00 pushq $0x0 <-- this is the number we want
* 3463e0102b: e9 e0 ff ff ff jmpq 3463e01010 <_init+0x18>
*
* 0000003463e01030 <fgetxattr@plt>:
* 3463e01030: ff 25 22 2c 20 00 jmpq *0x202c22(%rip)
* 3463e01036: 68 01 00 00 00 pushq $0x1
* 3463e0103b: e9 d0 ff ff ff jmpq 3463e01010 <_init+0x18>
*/
struct sr_elf_plt_entry *result = NULL, *last = NULL;
for (unsigned plt_offset = 16; plt_offset < plt_data->d_size; plt_offset += 16)
{
uint32_t *plt_index = (uint32_t*)(plt_data->d_buf + plt_offset + 7);
GElf_Rela rela;
if (gelf_getrela(rela_plt_data, *plt_index, &rela) != &rela)
{
*error_message = sr_asprintf("gelf_getrela failed for %s: %s",
filename,
elf_errmsg(-1));
sr_elf_procedure_linkage_table_free(result);
elf_end(elf);
close(fd);
return NULL;
}
GElf_Sym symb;
if (gelf_getsym(plt_symbols, GELF_R_SYM(rela.r_info), &symb) != &symb)
{
*error_message = sr_asprintf("gelf_getsym failed for %s: %s",
filename,
elf_errmsg(-1));
sr_elf_procedure_linkage_table_free(result);
elf_end(elf);
close(fd);
return NULL;
}
struct sr_elf_plt_entry *entry = sr_malloc(sizeof(struct sr_elf_plt_entry));
entry->symbol_name = sr_strdup(elf_strptr(elf, stringtable,
symb.st_name));
entry->address = (uint64_t)(plt_base + plt_offset);
entry->next = NULL;
if (result)
{
last->next = entry;
last = entry;
}
else
result = last = entry;
}
elf_end(elf);
close(fd);
return result;
#else /* WITH_ELFUTILS */
*error_message = sr_asprintf("satyr compiled without elfutils");
return NULL;
#endif /* WITH_ELFUTILS */
}
struct sr_disasm_state *
sr_disasm_init(const char *file_name,
char **error_message)
{
#if HAVE_LIBOPCODES
struct sr_disasm_state *state =
sr_malloc(sizeof(struct sr_disasm_state));
state->bfd_file = bfd_openr(file_name, NULL);
if (!state->bfd_file)
{
*error_message = sr_asprintf("Failed to open file %s: %s",
file_name,
bfd_errmsg(bfd_get_error()));
free(state);
return NULL;
}
if (!bfd_check_format(state->bfd_file, bfd_object))
{
*error_message = sr_asprintf("Invalid file format of %s: %s",
file_name,
bfd_errmsg(bfd_get_error()));
bfd_close(state->bfd_file);
free(state);
return NULL;
}
asection *section =
bfd_get_section_by_name(state->bfd_file, ".text");
if (!section)
{
*error_message = sr_asprintf(
"Failed to find .text section in %s: %s",
file_name,
bfd_errmsg(bfd_get_error()));
bfd_close(state->bfd_file);
free(state);
return NULL;
}
state->disassembler = disassembler(state->bfd_file);
if (!state->disassembler)
{
*error_message = sr_asprintf(
"Unable to find disassembler for %s",
file_name);
bfd_close(state->bfd_file);
free(state);
return NULL;
}
init_disassemble_info(&state->info, NULL, buffer_printf);
state->info.arch = bfd_get_arch(state->bfd_file);
state->info.mach = bfd_get_mach(state->bfd_file);
state->info.buffer_vma = section->vma;
state->info.buffer_length = section->size;
state->info.section = section;
/* TODO: memory error func */
bfd_malloc_and_get_section(state->bfd_file, section,
&state->info.buffer);
disassemble_init_for_target(&state->info);
return state;
#else // HAVE_LIBOPCODES
*error_message = sr_asprintf("satyr compiled without libopcodes");
return NULL;
#endif // HAVE_LIBOPCODES
}
static struct sr_core_thread *
unwind_thread(struct UCD_info *ui,
unw_addr_space_t as,
Dwfl *dwfl,
int thread_no,
char **error_msg)
{
int ret;
unw_cursor_t c;
struct sr_core_frame *trace = NULL;
_UCD_select_thread(ui, thread_no);
ret = unw_init_remote(&c, as, ui);
if (ret < 0)
{
set_error("unw_init_remote failed: %s", unw_strerror(ret));
return NULL;
}
int count = 1000;
while (--count > 0)
{
unw_word_t ip;
ret = unw_get_reg(&c, UNW_REG_IP, &ip);
if (ret < 0)
warn("unw_get_reg(UNW_REG_IP) failed: %s", unw_strerror(ret));
/* Seen this happen when unwinding thread that did not start
* in main(). */
if (ip == 0)
break;
struct sr_core_frame *entry = resolve_frame(dwfl, ip, false);
if (!entry->function_name)
{
size_t funcname_len = 512;
char *funcname = sr_malloc(funcname_len);
if (unw_get_proc_name(&c, funcname, funcname_len, NULL) == 0)
entry->function_name = funcname;
else
free(funcname);
}
trace = sr_core_frame_append(trace, entry);
/*
printf("%s 0x%llx %s %s -\n",
(ip_seg && ip_seg->build_id) ? ip_seg->build_id : "-",
(unsigned long long)(ip_seg ? ip - ip_seg->vaddr : ip),
(entry->symbol ? entry->symbol : "-"),
(ip_seg && ip_seg->filename) ? ip_seg->filename : "-");
*/
/* Do not unwind below __libc_start_main. */
if (0 == sr_strcmp0(entry->function_name, "__libc_start_main"))
break;
ret = unw_step(&c);
if (ret == 0)
break;
if (ret < 0)
{
warn("unw_step failed: %s", unw_strerror(ret));
break;
}
}
if (error_msg && !*error_msg && !trace)
{
set_error("No frames found for thread %d", thread_no);
}
struct sr_core_thread *thread = sr_core_thread_new();
thread->frames = trace;
return thread;
}
