micropython/extmod/modbinascii.c
Jim Mussared 3533924c36 extmod/moddeflate: Add deflate module providing the DeflateIO class.
This provides similar functionality to the former zlib.DecompIO and
especially CPython's gzip.GzipFile for both compression and decompression.

This class can be used directly, and also can be used from Python to
implement (via io.BytesIO) zlib.decompress and zlib.compress, as well as
gzip.GzipFile.

Enable/disable this on all ports/boards that zlib was previously configured
for.

This work was funded through GitHub Sponsors.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2023-07-21 19:32:40 +10:00

209 lines
7.1 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2014 Paul Sokolovsky
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include <assert.h>
#include <string.h>
#include "py/runtime.h"
#include "py/binary.h"
#include "py/objstr.h"
#if MICROPY_PY_BINASCII
#if MICROPY_PY_BUILTINS_BYTES_HEX
STATIC mp_obj_t bytes_hex_as_bytes(size_t n_args, const mp_obj_t *args) {
return mp_obj_bytes_hex(n_args, args, &mp_type_bytes);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(bytes_hex_as_bytes_obj, 1, 2, bytes_hex_as_bytes);
STATIC mp_obj_t bytes_fromhex_bytes(mp_obj_t data) {
return mp_obj_bytes_fromhex(MP_OBJ_FROM_PTR(&mp_type_bytes), data);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(bytes_fromhex_obj, bytes_fromhex_bytes);
#endif
// If ch is a character in the base64 alphabet, and is not a pad character, then
// the corresponding integer between 0 and 63, inclusively, is returned.
// Otherwise, -1 is returned.
static int mod_binascii_sextet(byte ch) {
if (ch >= 'A' && ch <= 'Z') {
return ch - 'A';
} else if (ch >= 'a' && ch <= 'z') {
return ch - 'a' + 26;
} else if (ch >= '0' && ch <= '9') {
return ch - '0' + 52;
} else if (ch == '+') {
return 62;
} else if (ch == '/') {
return 63;
} else {
return -1;
}
}
STATIC mp_obj_t mod_binascii_a2b_base64(mp_obj_t data) {
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(data, &bufinfo, MP_BUFFER_READ);
byte *in = bufinfo.buf;
vstr_t vstr;
vstr_init(&vstr, (bufinfo.len * 3) / 4 + 1); // Potentially over-allocate
byte *out = (byte *)vstr.buf;
uint shift = 0;
int nbits = 0; // Number of meaningful bits in shift
bool hadpad = false; // Had a pad character since last valid character
for (size_t i = 0; i < bufinfo.len; i++) {
if (in[i] == '=') {
if ((nbits == 2) || ((nbits == 4) && hadpad)) {
nbits = 0;
break;
}
hadpad = true;
}
int sextet = mod_binascii_sextet(in[i]);
if (sextet == -1) {
continue;
}
hadpad = false;
shift = (shift << 6) | sextet;
nbits += 6;
if (nbits >= 8) {
nbits -= 8;
out[vstr.len++] = (shift >> nbits) & 0xFF;
}
}
if (nbits) {
mp_raise_ValueError(MP_ERROR_TEXT("incorrect padding"));
}
return mp_obj_new_bytes_from_vstr(&vstr);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(mod_binascii_a2b_base64_obj, mod_binascii_a2b_base64);
STATIC mp_obj_t mod_binascii_b2a_base64(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
enum { ARG_newline };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_newline, MP_ARG_BOOL, {.u_bool = true} },
};
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
uint8_t newline = args[ARG_newline].u_bool;
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(pos_args[0], &bufinfo, MP_BUFFER_READ);
vstr_t vstr;
vstr_init_len(&vstr, ((bufinfo.len != 0) ? (((bufinfo.len - 1) / 3) + 1) * 4 : 0) + newline);
// First pass, we convert input buffer to numeric base 64 values
byte *in = bufinfo.buf, *out = (byte *)vstr.buf;
mp_uint_t i;
for (i = bufinfo.len; i >= 3; i -= 3) {
*out++ = (in[0] & 0xFC) >> 2;
*out++ = (in[0] & 0x03) << 4 | (in[1] & 0xF0) >> 4;
*out++ = (in[1] & 0x0F) << 2 | (in[2] & 0xC0) >> 6;
*out++ = in[2] & 0x3F;
in += 3;
}
if (i != 0) {
*out++ = (in[0] & 0xFC) >> 2;
if (i == 2) {
*out++ = (in[0] & 0x03) << 4 | (in[1] & 0xF0) >> 4;
*out++ = (in[1] & 0x0F) << 2;
} else {
*out++ = (in[0] & 0x03) << 4;
*out++ = 64;
}
*out = 64;
}
// Second pass, we convert number base 64 values to actual base64 ascii encoding
out = (byte *)vstr.buf;
for (mp_uint_t j = vstr.len - newline; j--;) {
if (*out < 26) {
*out += 'A';
} else if (*out < 52) {
*out += 'a' - 26;
} else if (*out < 62) {
*out += '0' - 52;
} else if (*out == 62) {
*out = '+';
} else if (*out == 63) {
*out = '/';
} else {
*out = '=';
}
out++;
}
if (newline) {
*out = '\n';
}
return mp_obj_new_bytes_from_vstr(&vstr);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mod_binascii_b2a_base64_obj, 1, mod_binascii_b2a_base64);
#if MICROPY_PY_BINASCII_CRC32 && MICROPY_PY_DEFLATE
#include "lib/uzlib/uzlib.h"
STATIC mp_obj_t mod_binascii_crc32(size_t n_args, const mp_obj_t *args) {
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(args[0], &bufinfo, MP_BUFFER_READ);
uint32_t crc = (n_args > 1) ? mp_obj_get_int_truncated(args[1]) : 0;
crc = uzlib_crc32(bufinfo.buf, bufinfo.len, crc ^ 0xffffffff);
return mp_obj_new_int_from_uint(crc ^ 0xffffffff);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_binascii_crc32_obj, 1, 2, mod_binascii_crc32);
#endif
STATIC const mp_rom_map_elem_t mp_module_binascii_globals_table[] = {
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_binascii) },
#if MICROPY_PY_BUILTINS_BYTES_HEX
{ MP_ROM_QSTR(MP_QSTR_hexlify), MP_ROM_PTR(&bytes_hex_as_bytes_obj) },
{ MP_ROM_QSTR(MP_QSTR_unhexlify), MP_ROM_PTR(&bytes_fromhex_obj) },
#endif
{ MP_ROM_QSTR(MP_QSTR_a2b_base64), MP_ROM_PTR(&mod_binascii_a2b_base64_obj) },
{ MP_ROM_QSTR(MP_QSTR_b2a_base64), MP_ROM_PTR(&mod_binascii_b2a_base64_obj) },
#if MICROPY_PY_BINASCII_CRC32 && MICROPY_PY_DEFLATE
{ MP_ROM_QSTR(MP_QSTR_crc32), MP_ROM_PTR(&mod_binascii_crc32_obj) },
#endif
};
STATIC MP_DEFINE_CONST_DICT(mp_module_binascii_globals, mp_module_binascii_globals_table);
const mp_obj_module_t mp_module_binascii = {
.base = { &mp_type_module },
.globals = (mp_obj_dict_t *)&mp_module_binascii_globals,
};
MP_REGISTER_EXTENSIBLE_MODULE(MP_QSTR_binascii, mp_module_binascii);
#endif // MICROPY_PY_BINASCII