/
buf.c
718 lines (643 loc) · 16.3 KB
/
buf.c
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/* radare - LGPL - Copyright 2009-2022 - ret2libc, pancake */
#include <r_types.h>
#include <r_util.h>
#include <r_io.h>
typedef enum {
R_BUFFER_FILE,
R_BUFFER_IO,
R_BUFFER_BYTES,
R_BUFFER_MMAP,
R_BUFFER_SPARSE,
R_BUFFER_REF,
} RBufferType;
#include "buf_file.c"
#include "buf_sparse.c"
#include "buf_bytes.c"
#include "buf_mmap.c"
#include "buf_io.c"
#include "buf_ref.c"
static bool buf_init(RBuffer *b, const void *user) {
r_return_val_if_fail (b && b->methods, false);
return b->methods->init? b->methods->init (b, user): true;
}
static void buf_wholefree(RBuffer *b) {
if (!b->methods->get_whole_buf) {
R_FREE (b->whole_buf);
}
}
static bool buf_fini(RBuffer *b) {
r_return_val_if_fail (b && b->methods, false);
return b->methods->fini? b->methods->fini (b): true;
}
static ut64 buf_get_size(RBuffer *b) {
r_return_val_if_fail (b && b->methods, UT64_MAX);
return b->methods->get_size? b->methods->get_size (b): UT64_MAX;
}
static st64 buf_read(RBuffer *b, ut8 *buf, size_t len) {
r_return_val_if_fail (b && b->methods, -1);
return b->methods->read? b->methods->read (b, buf, len): -1;
}
static st64 buf_write(RBuffer *b, const ut8 *buf, size_t len) {
r_return_val_if_fail (b && b->methods, -1);
buf_wholefree (b);
return b->methods->write? b->methods->write (b, buf, len): -1;
}
static st64 buf_seek(RBuffer *b, st64 addr, int whence) {
r_return_val_if_fail (b && b->methods, -1);
return b->methods->seek? b->methods->seek (b, addr, whence): -1;
}
static bool buf_resize(RBuffer *b, ut64 newsize) {
r_return_val_if_fail (b && b->methods, -1);
return b->methods->resize? b->methods->resize (b, newsize): false;
}
static ut8 *get_whole_buf(RBuffer *b, ut64 *sz) {
r_return_val_if_fail (b && b->methods, NULL);
if (b->methods->get_whole_buf) {
return b->methods->get_whole_buf (b, sz);
}
ut64 bsz = r_buf_size (b);
// bsz = 4096; // FAKE MINIMUM SIZE TO READ THE BIN HEADER
if (bsz == UT64_MAX) {
return NULL;
}
free (b->whole_buf);
b->whole_buf = R_NEWS (ut8, bsz);
if (!b->whole_buf) {
return NULL;
}
r_buf_read_at (b, 0, b->whole_buf, bsz);
if (sz) {
*sz = bsz;
}
return b->whole_buf;
}
static RBuffer *new_buffer(RBufferType type, const void *user) {
RBuffer *b = R_NEW0 (RBuffer);
if (!b) {
return NULL;
}
switch (type) {
case R_BUFFER_BYTES:
b->methods = &buffer_bytes_methods;
break;
case R_BUFFER_MMAP:
b->methods = &buffer_mmap_methods;
break;
case R_BUFFER_SPARSE:
b->methods = &buffer_sparse_methods;
break;
case R_BUFFER_FILE:
b->methods = &buffer_file_methods;
break;
case R_BUFFER_IO:
b->methods = &buffer_io_methods;
break;
case R_BUFFER_REF:
b->methods = &buffer_ref_methods;
break;
default:
r_warn_if_reached ();
break;
}
if (!buf_init (b, user)) {
free (b);
return NULL;
}
return b;
}
// TODO: Optimize to use memcpy when buffers are not in range..
// check buf boundaries and offsets and use memcpy or memmove
// copied from libr/io/cache.c:r_io_cache_read
// ret # of bytes copied
R_API RBuffer *r_buf_new_with_io(void *iob, int fd) {
r_return_val_if_fail (iob && fd >= 0, NULL);
struct buf_io_user u = { 0 };
u.iob = (RIOBind *)iob;
u.fd = fd;
return new_buffer (R_BUFFER_IO, &u);
}
R_API RBuffer *r_buf_new_with_pointers(const ut8 *bytes, ut64 len, bool steal) {
struct buf_bytes_user u = { 0 };
u.data_steal = bytes;
u.length = len;
u.steal = steal;
return new_buffer (R_BUFFER_BYTES, &u);
}
R_API RBuffer *r_buf_new_empty(ut64 len) {
ut8 *buf = R_NEWS0 (ut8, len);
if (!buf) {
return NULL;
}
struct buf_bytes_user u = { 0 };
u.data_steal = buf;
u.length = len;
u.steal = true;
RBuffer *res = new_buffer (R_BUFFER_BYTES, &u);
if (!res) {
free (buf);
}
return res;
}
R_API RBuffer *r_buf_new_with_bytes(const ut8 *bytes, ut64 len) {
struct buf_bytes_user u = { 0 };
u.data = bytes;
u.length = len;
return new_buffer (R_BUFFER_BYTES, &u);
}
R_API RBuffer *r_buf_new_slice(RBuffer *b, ut64 offset, ut64 size) {
struct buf_ref_user u = { 0 };
u.parent = b;
u.offset = offset;
u.size = size;
return new_buffer (R_BUFFER_REF, &u);
}
R_API RBuffer *r_buf_new_with_string(const char *msg) {
return r_buf_new_with_bytes ((const ut8 *)msg, (ut64)strlen (msg));
}
R_API RBuffer *r_buf_new_with_buf(RBuffer *b) {
ut64 sz = 0;
const ut8 *tmp = r_buf_data (b, &sz);
return r_buf_new_with_bytes (tmp, sz);
}
R_API RBuffer *r_buf_new_sparse(ut8 Oxff) {
RBuffer *b = new_buffer (R_BUFFER_SPARSE, NULL);
if (b) {
b->Oxff_priv = Oxff;
}
return b;
}
R_API RBuffer *r_buf_new(void) {
struct buf_bytes_user u = { 0 };
u.data = NULL;
u.length = 0;
return new_buffer (R_BUFFER_BYTES, &u);
}
R_DEPRECATE R_API const ut8 *r_buf_data(RBuffer *b, ut64 *size) {
r_return_val_if_fail (b, NULL);
b->whole_buf = get_whole_buf (b, size);
return b->whole_buf;
}
R_API ut64 r_buf_size(RBuffer *b) {
r_return_val_if_fail (b, 0);
return buf_get_size (b);
}
// rename to new?
R_API RBuffer *r_buf_new_mmap(const char *filename, int perm) {
r_return_val_if_fail (filename, NULL);
struct buf_mmap_user u = { 0 };
u.filename = filename;
u.perm = perm;
return new_buffer (R_BUFFER_MMAP, &u);
}
R_API RBuffer *r_buf_new_file(const char *file, int perm, int mode) {
struct buf_file_user u = { 0 };
u.file = file;
u.perm = perm;
u.mode = mode;
return new_buffer (R_BUFFER_FILE, &u);
}
// TODO: rename to new_from_file ?
R_API RBuffer *r_buf_new_slurp(const char *file) {
size_t len;
char *tmp = r_file_slurp (file, &len);
if (!tmp) {
return NULL;
}
struct buf_bytes_user u = { 0 };
u.data_steal = (ut8 *)tmp;
u.length = (ut64)len;
u.steal = true;
return new_buffer (R_BUFFER_BYTES, &u);
}
R_API bool r_buf_dump(RBuffer *b, const char *file) {
// TODO: need to redo this
if (!b || !file) {
return false;
}
ut64 tmpsz = 0;
const ut8 *tmp = r_buf_data (b, &tmpsz);
return r_file_dump (file, tmp, tmpsz, 0);
}
R_API st64 r_buf_seek(RBuffer *b, st64 addr, int whence) {
r_return_val_if_fail (b, -1);
return buf_seek (b, addr, whence);
}
R_API ut64 r_buf_tell(RBuffer *b) {
return r_buf_seek (b, 0, R_BUF_CUR);
}
R_API bool r_buf_set_bytes(RBuffer *b, const ut8 *buf, ut64 length) {
r_return_val_if_fail (b && buf && !b->readonly, false);
if (!r_buf_resize (b, 0)) {
return false;
}
if (r_buf_seek (b, 0, R_BUF_SET) < 0) {
return false;
}
if (!r_buf_append_bytes (b, buf, length)) {
return false;
}
return r_buf_seek (b, 0, R_BUF_SET) >= 0;
}
R_API bool r_buf_prepend_bytes(RBuffer *b, const ut8 *buf, ut64 length) {
r_return_val_if_fail (b && buf && !b->readonly, false);
return r_buf_insert_bytes (b, 0, buf, length) >= 0;
}
R_API char *r_buf_to_string(RBuffer *b) {
ut64 sz = r_buf_size (b);
char *s = malloc (sz + 1);
if (!s) {
return NULL;
}
if (r_buf_read_at (b, 0, (ut8 *)s, sz) < 0) {
free (s);
return NULL;
}
s[sz] = '\0';
return s;
}
R_API bool r_buf_append_bytes(RBuffer *b, const ut8 *buf, ut64 length) {
r_return_val_if_fail (b && buf && !b->readonly, false);
if (r_buf_seek (b, 0, R_BUF_END) < 0) {
return false;
}
return r_buf_write (b, buf, length) >= 0;
}
R_API bool r_buf_append_nbytes(RBuffer *b, ut64 length) {
r_return_val_if_fail (b && !b->readonly, false);
ut8 *buf = R_NEWS0 (ut8, length);
if (!buf) {
return false;
}
bool res = r_buf_append_bytes (b, buf, length);
free (buf);
return res;
}
R_API st64 r_buf_insert_bytes(RBuffer *b, ut64 addr, const ut8 *buf, ut64 length) {
r_return_val_if_fail (b && !b->readonly, -1);
st64 pos, r = r_buf_seek (b, 0, R_BUF_CUR);
if (r < 0) {
return r;
}
pos = r;
r = r_buf_seek (b, addr, R_BUF_SET);
if (r < 0) {
goto restore_pos;
}
ut64 sz = r_buf_size (b);
ut8 *tmp = R_NEWS (ut8, sz - addr);
r = r_buf_read (b, tmp, sz - addr);
if (r < 0) {
goto free_tmp;
}
st64 tmp_length = r;
if (!r_buf_resize (b, sz + length)) {
goto free_tmp;
}
r = r_buf_seek (b, addr + length, R_BUF_SET);
if (r < 0) {
goto free_tmp;
}
r = r_buf_write (b, tmp, tmp_length);
if (r < 0) {
goto free_tmp;
}
r = r_buf_seek (b, addr, R_BUF_SET);
if (r < 0) {
goto free_tmp;
}
r = r_buf_write (b, buf, length);
free_tmp:
free (tmp);
restore_pos:
r_buf_seek (b, pos, R_BUF_SET);
return r;
}
R_API bool r_buf_append_ut8(RBuffer *b, ut8 n) {
r_return_val_if_fail (b && !b->readonly, false);
return r_buf_append_bytes (b, (const ut8 *)&n, sizeof (n));
}
R_API bool r_buf_append_ut16(RBuffer *b, ut16 n) {
r_return_val_if_fail (b && !b->readonly, false);
return r_buf_append_bytes (b, (const ut8 *)&n, sizeof (n));
}
R_API bool r_buf_append_ut32(RBuffer *b, ut32 n) {
r_return_val_if_fail (b && !b->readonly, false);
return r_buf_append_bytes (b, (const ut8 *)&n, sizeof (n));
}
R_API bool r_buf_append_ut64(RBuffer *b, ut64 n) {
r_return_val_if_fail (b && !b->readonly, false);
return r_buf_append_bytes (b, (const ut8 *)&n, sizeof (n));
}
R_API bool r_buf_append_buf(RBuffer *b, RBuffer *a) {
r_return_val_if_fail (b && a && !b->readonly, false);
ut64 sz = 0;
const ut8 *tmp = r_buf_data (a, &sz);
return r_buf_append_bytes (b, tmp, sz);
}
R_API bool r_buf_append_buf_slice(RBuffer *b, RBuffer *a, ut64 offset, ut64 size) {
r_return_val_if_fail (b && a && !b->readonly, false);
ut8 *tmp = R_NEWS (ut8, size);
bool res = false;
if (!tmp) {
return false;
}
st64 r = r_buf_read_at (a, offset, tmp, size);
if (r < 0) {
goto err;
}
res = r_buf_append_bytes (b, tmp, r);
err:
free (tmp);
return res;
}
// return an heap-allocated string read from the RBuffer b at address addr. The
// length depends on the first '\0' found in the buffer. If there is no '\0' in
// the buffer, there is no string, thus NULL is returned.
R_API char *r_buf_get_string(RBuffer *b, ut64 addr) {
const int MIN_RES_SZ = 64;
ut8 *res = R_NEWS (ut8, MIN_RES_SZ + 1);
ut64 sz = 0;
st64 r = r_buf_read_at (b, addr, res, MIN_RES_SZ);
bool null_found = false;
while (r > 0) {
const ut8 *needle = r_mem_mem (res + sz, r, (ut8 *)"\x00", 1);
if (needle) {
null_found = true;
break;
}
sz += r;
addr += r;
ut8 *restmp = realloc (res, sz + MIN_RES_SZ + 1);
if (!restmp) {
free (res);
return NULL;
}
res = restmp;
r = r_buf_read_at (b, addr, res + sz, MIN_RES_SZ);
}
if (r < 0 || !null_found) {
free (res);
return NULL;
}
return (char *)res;
}
R_API ut8 *r_buf_read_all(RBuffer *b, int *blen) {
r_return_val_if_fail (b, NULL);
int buflen = r_buf_size (b);
if (buflen < 0) {
return NULL;
}
ut8 *buf = malloc (buflen + 1);
buf_seek (b, 0, R_BUF_SET);
buf_read (b, buf, buflen);
if (blen) {
*blen = buflen;
}
return buf;
}
R_API st64 r_buf_read(RBuffer *b, ut8 *buf, ut64 len) {
r_return_val_if_fail (b && buf, -1);
st64 r = buf_read (b, buf, len);
if (r >= 0 && r < len) {
memset (buf + r, b->Oxff_priv, len - r);
}
return r;
}
R_API st64 r_buf_write(RBuffer *b, const ut8 *buf, ut64 len) {
r_return_val_if_fail (b && buf && !b->readonly, -1);
return buf_write (b, buf, len);
}
R_API ut8 r_buf_read8(RBuffer *b) {
ut8 res;
st64 r = r_buf_read (b, &res, sizeof (res));
return r == sizeof (res)? res: b->Oxff_priv;
}
R_API ut8 r_buf_read8_at(RBuffer *b, ut64 addr) {
ut8 res;
st64 r = r_buf_read_at (b, addr, &res, sizeof (res));
return r == sizeof (res)? res: b->Oxff_priv;
}
static st64 buf_format(RBuffer *dst, RBuffer *src, const char *fmt, int n) {
st64 res = 0;
int i;
for (i = 0; i < n; i++) {
int j;
int m = 1;
int tsize = 2;
bool bigendian = true;
for (j = 0; fmt[j]; j++) {
switch (fmt[j]) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if (m == 1) {
m = r_num_get (NULL, &fmt[j]);
}
continue;
case 's': tsize = 2; bigendian = false; break;
case 'S': tsize = 2; bigendian = true; break;
case 'i': tsize = 4; bigendian = false; break;
case 'I': tsize = 4; bigendian = true; break;
case 'l': tsize = 8; bigendian = false; break;
case 'L': tsize = 8; bigendian = true; break;
case 'c': tsize = 1; bigendian = false; break;
default: return -1;
}
int k;
for (k = 0; k < m; k++) {
ut8 tmp[sizeof (ut64)];
ut8 d1;
ut16 d2;
ut32 d3;
ut64 d4;
st64 r = r_buf_read (src, tmp, tsize);
if (r != tsize) {
return -1;
}
switch (tsize) {
case 1:
d1 = r_read_ble8 (tmp);
r = r_buf_write (dst, (ut8 *)&d1, 1);
break;
case 2:
d2 = r_read_ble16 (tmp, bigendian);
r = r_buf_write (dst, (ut8 *)&d2, 2);
break;
case 4:
d3 = r_read_ble32 (tmp, bigendian);
r = r_buf_write (dst, (ut8 *)&d3, 4);
break;
case 8:
d4 = r_read_ble64 (tmp, bigendian);
r = r_buf_write (dst, (ut8 *)&d4, 8);
break;
}
if (r < 0) {
return -1;
}
res += r;
}
m = 1;
}
}
return res;
}
R_API st64 r_buf_fread(RBuffer *b, ut8 *buf, const char *fmt, int n) {
r_return_val_if_fail (b && buf && fmt, -1);
// XXX: we assume the caller knows what he's doing
RBuffer *dst = r_buf_new_with_pointers (buf, UT64_MAX, false);
st64 res = buf_format (dst, b, fmt, n);
r_buf_free (dst);
return res;
}
R_API st64 r_buf_fread_at(RBuffer *b, ut64 addr, ut8 *buf, const char *fmt, int n) {
r_return_val_if_fail (b && buf && fmt, -1);
st64 o_addr = r_buf_seek (b, 0, R_BUF_CUR);
st64 r = r_buf_seek (b, addr, R_BUF_SET);
if (r < 0) {
return r;
}
r = r_buf_fread (b, buf, fmt, n);
(void)r_buf_seek (b, o_addr, R_BUF_SET);
return r;
}
R_API st64 r_buf_fwrite(RBuffer *b, const ut8 *buf, const char *fmt, int n) {
r_return_val_if_fail (b && buf && fmt && !b->readonly, -1);
// XXX: we assume the caller knows what he's doing
RBuffer *src = r_buf_new_with_pointers (buf, UT64_MAX, false);
st64 res = buf_format (b, src, fmt, n);
r_buf_free (src);
return res;
}
R_API st64 r_buf_fwrite_at(RBuffer *b, ut64 addr, const ut8 *buf, const char *fmt, int n) {
r_return_val_if_fail (b && buf && fmt && !b->readonly, -1);
st64 o_addr = r_buf_seek (b, 0, R_BUF_CUR);
st64 r = r_buf_seek (b, addr, R_BUF_SET);
if (r < 0) {
return r;
}
r = r_buf_fwrite (b, buf, fmt, n);
r_buf_seek (b, o_addr, R_BUF_SET);
return r;
}
R_API st64 r_buf_read_at(RBuffer *b, ut64 addr, ut8 *buf, ut64 len) {
r_return_val_if_fail (b && buf, -1);
st64 o_addr = r_buf_seek (b, 0, R_BUF_CUR);
st64 r = r_buf_seek (b, addr, R_BUF_SET);
if (r < 0) {
return r;
}
r = r_buf_read (b, buf, len);
r_buf_seek (b, o_addr, R_BUF_SET);
return r;
}
R_API st64 r_buf_write_at(RBuffer *b, ut64 addr, const ut8 *buf, ut64 len) {
r_return_val_if_fail (b && buf && !b->readonly, -1);
st64 o_addr = r_buf_seek (b, 0, R_BUF_CUR);
st64 r = r_buf_seek (b, addr, R_BUF_SET);
if (r < 0) {
return r;
}
r = r_buf_write (b, buf, len);
r_buf_seek (b, o_addr, R_BUF_SET);
return r;
}
R_API void r_buf_fini(RBuffer *b) {
if (!b) {
return;
}
if (b->refctr > 0) {
b->refctr--;
return;
}
// free the whole_buf only if it was initially allocated by the buf types
if (b->methods->get_whole_buf) {
if (b->methods->free_whole_buf) {
b->methods->free_whole_buf (b);
}
} else {
buf_wholefree (b);
}
buf_fini (b);
}
R_API void r_buf_free(RBuffer *b) {
bool unreferenced = b && b->refctr == 0;
r_buf_fini (b);
if (unreferenced) {
free (b);
}
}
R_API st64 r_buf_append_string(RBuffer *b, const char *str) {
r_return_val_if_fail (b && str && !b->readonly, false);
return r_buf_append_bytes (b, (const ut8 *)str, strlen (str));
}
R_API bool r_buf_resize(RBuffer *b, ut64 newsize) {
r_return_val_if_fail (b, false);
return buf_resize (b, newsize);
}
R_API RBuffer *r_buf_ref(RBuffer *b) {
if (b) {
b->refctr++;
}
return b;
}
R_API RList *r_buf_nonempty_list(RBuffer *b) {
return b->methods->nonempty_list? b->methods->nonempty_list (b): NULL;
}
R_API st64 r_buf_uleb128(RBuffer *b, ut64 *v) {
ut8 c = 0xff;
ut64 s = 0, sum = 0, l = 0;
do {
ut8 data;
st64 r = r_buf_read (b, &data, sizeof (data));
if (r < 1) {
return -1;
}
c = data & 0xff;
if (s < 64) {
sum |= ((ut64) (c & 0x7f) << s);
s += 7;
} else {
sum = 0;
}
l++;
} while (c & 0x80);
if (v) {
*v = sum;
}
return l;
}
R_API st64 r_buf_sleb128(RBuffer *b, st64 *v) {
st64 result = 0, offset = 0;
ut8 value;
do {
st64 chunk;
st64 r = r_buf_read (b, &value, sizeof (value));
if (r != sizeof (value)) {
return -1;
}
chunk = value & 0x7f;
if (offset < 64) {
result |= (chunk << offset);
offset += 7;
} else {
result = 0;
}
} while (value & 0x80);
if ((value & 0x40) != 0) {
if (offset < 64) {
result |= ~0ULL << offset;
}
}
if (v) {
*v = result;
}
return offset / 7;
}