Welcome! Log In Create A New Profile

Advanced

[njs] String.bytesFrom() method.

Dmitry Volyntsev
July 18, 2018 08:44AM
details: http://hg.nginx.org/njs/rev/9322e8eab0b6
branches:
changeset: 560:9322e8eab0b6
user: Dmitry Volyntsev <xeioex@nginx.com>
date: Wed Jul 18 15:41:55 2018 +0300
description:
String.bytesFrom() method.

The method creates a byte string from an array containing octets:
String.bytesFrom(array).

The method creates a byte string from an encoded string:
String.bytesFrom(string, encoding)
where encoding are "hex", "base64", "base64url".

This closes #2 issue on Github.

diffstat:

njs/njs_number.c | 21 +--
njs/njs_number.h | 23 +++
njs/njs_string.c | 315 +++++++++++++++++++++++++++++++++++++++++++++++
njs/njs_string.h | 7 +
njs/test/njs_unit_test.c | 63 +++++++++
5 files changed, 413 insertions(+), 16 deletions(-)

diffs (534 lines):

diff -r 729072cc162f -r 9322e8eab0b6 njs/njs_number.c
--- a/njs/njs_number.c Tue Jul 17 20:25:47 2018 +0300
+++ b/njs/njs_number.c Wed Jul 18 15:41:55 2018 +0300
@@ -215,8 +215,8 @@ njs_number_bin_parse(const u_char **star
uint64_t
njs_number_hex_parse(const u_char **start, const u_char *end)
{
- u_char c;
uint64_t num;
+ nxt_int_t n;
const u_char *p;

p = *start;
@@ -224,23 +224,12 @@ njs_number_hex_parse(const u_char **star
num = 0;

while (p < end) {
- c = (u_char) (*p | 0x20);
-
- /* Values less than '0' become >= 208. */
- c = c - '0';
-
- if (c > 9) {
- /* Values less than 'a' become >= 159. */
- c = c - ('a' - '0');
-
- if (nxt_slow_path(c > 5)) {
- break;
- }
-
- c += 10;
+ n = njs_char_to_hex(*p);
+ if (nxt_slow_path(n < 0)) {
+ break;
}

- num = num * 16 + c;
+ num = num * 16 + n;
p++;
}

diff -r 729072cc162f -r 9322e8eab0b6 njs/njs_number.h
--- a/njs/njs_number.h Tue Jul 17 20:25:47 2018 +0300
+++ b/njs/njs_number.h Wed Jul 18 15:41:55 2018 +0300
@@ -34,6 +34,29 @@ njs_ret_t njs_number_parse_float(njs_vm_
nxt_noinline uint32_t njs_number_to_integer(double num);


+nxt_inline nxt_int_t
+njs_char_to_hex(u_char c)
+{
+ c |= 0x20;
+
+ /* Values less than '0' become >= 208. */
+ c = c - '0';
+
+ if (c > 9) {
+ /* Values less than 'a' become >= 159. */
+ c = c - ('a' - '0');
+
+ if (nxt_slow_path(c > 5)) {
+ return -1;
+ }
+
+ c += 10;
+ }
+
+ return c;
+}
+
+
extern const njs_object_init_t njs_number_constructor_init;
extern const njs_object_init_t njs_number_prototype_init;

diff -r 729072cc162f -r 9322e8eab0b6 njs/njs_string.c
--- a/njs/njs_string.c Tue Jul 17 20:25:47 2018 +0300
+++ b/njs/njs_string.c Wed Jul 18 15:41:55 2018 +0300
@@ -56,12 +56,20 @@ typedef struct {

static void njs_encode_base64_core(nxt_str_t *dst, const nxt_str_t *src,
const u_char *basis, nxt_uint_t padding);
+static njs_ret_t njs_decode_base64_core(njs_vm_t *vm,
+ njs_value_t *value, const nxt_str_t *src, const u_char *basis);
static nxt_noinline void njs_string_slice_prop(njs_string_prop_t *string,
njs_slice_prop_t *slice, njs_value_t *args, nxt_uint_t nargs);
static nxt_noinline void njs_string_slice_args(njs_slice_prop_t *slice,
njs_value_t *args, nxt_uint_t nargs);
static njs_ret_t njs_string_from_char_code(njs_vm_t *vm,
njs_value_t *args, nxt_uint_t nargs, njs_index_t unused);
+static njs_ret_t njs_string_bytes_from(njs_vm_t *vm, njs_value_t *args,
+ nxt_uint_t nargs, njs_index_t unused);
+static njs_ret_t njs_string_bytes_from_array(njs_vm_t *vm,
+ const njs_value_t *value);
+static njs_ret_t njs_string_bytes_from_string(njs_vm_t *vm,
+ const njs_value_t *args, nxt_uint_t nargs);
static njs_ret_t njs_string_starts_or_ends_with(njs_vm_t *vm, njs_value_t *args,
nxt_uint_t nargs, nxt_bool_t starts);
static njs_ret_t njs_string_prototype_pad(njs_vm_t *vm, njs_value_t *args,
@@ -99,6 +107,7 @@ static njs_ret_t njs_string_decode(njs_v


#define njs_base64_encoded_length(len) (((len + 2) / 3) * 4)
+#define njs_base64_decoded_length(len) (((len + 3) / 4) * 3)


njs_ret_t
@@ -165,6 +174,8 @@ njs_string_new(njs_vm_t *vm, njs_value_t
return NXT_OK;
}

+ njs_memory_error(vm);
+
return NXT_ERROR;
}

@@ -222,10 +233,41 @@ njs_string_alloc(njs_vm_t *vm, njs_value
return string->start;
}

+ njs_memory_error(vm);
+
return NULL;
}


+void
+njs_string_truncate(njs_value_t *value, uint32_t size)
+{
+ u_char *dst, *src;
+
+ if (size <= NJS_STRING_SHORT) {
+ if (value->short_string.size != NJS_STRING_LONG) {
+ value->short_string.size = size;
+
+ } else {
+ value->short_string.size = size;
+ dst = value->short_string.start;
+ src = value->long_string.data->start;
+
+ while (size != 0) {
+ /* The maximum size is just 14 bytes. */
+ nxt_pragma_loop_disable_vectorization;
+
+ *dst++ = *src++;
+ size--;
+ }
+ }
+
+ } else {
+ value->long_string.size = size;
+ }
+}
+
+
nxt_noinline njs_ret_t
njs_string_hex(njs_vm_t *vm, njs_value_t *value, const nxt_str_t *src)
{
@@ -552,6 +594,15 @@ static const njs_object_prop_t njs_stri
.value = njs_prop_handler(njs_object_prototype_create),
},

+ /* String.bytesFrom(). */
+ {
+ .type = NJS_METHOD,
+ .name = njs_string("bytesFrom"),
+ .value = njs_native_function(njs_string_bytes_from, 0, NJS_SKIP_ARG,
+ NJS_SKIP_ARG, NJS_STRING_ARG),
+ },
+
+
/* String.fromCharCode(). */
{
.type = NJS_METHOD,
@@ -1331,6 +1382,270 @@ done:
}


+/*
+ * String.bytesFrom(array).
+ * Converts an array containing octets into a byte string.
+ *
+ * String.bytesFrom(string[, encoding]).
+ * Converts a string using provided encoding: hex, base64, base64url to
+ * a byte string.
+ */
+
+static njs_ret_t
+njs_string_bytes_from(njs_vm_t *vm, njs_value_t *args, nxt_uint_t nargs,
+ njs_index_t unused)
+{
+ const njs_value_t *value;
+
+ value = njs_arg(args, nargs, 1);
+
+ if (njs_is_string(value)) {
+ return njs_string_bytes_from_string(vm, args, nargs);
+ }
+
+ if (njs_is_array(value)) {
+ return njs_string_bytes_from_array(vm, njs_arg(args, nargs, 1));
+ }
+
+ njs_type_error(vm, "value must be a string or array");
+
+ return NJS_ERROR;
+}
+
+
+static njs_ret_t
+njs_string_bytes_from_array(njs_vm_t *vm, const njs_value_t *value)
+{
+ u_char *p;
+ uint32_t i, length;
+ njs_array_t *array;
+ njs_value_t *octet;
+
+ array = value->data.u.array;
+ length = array->length;
+
+ for (i = 0; i < length; i++) {
+ if (!njs_is_numeric(&array->start[i])) {
+ njs_vm_trap_value(vm, &array->start[i]);
+ return NJS_TRAP_NUMBER_ARG;
+ }
+ }
+
+ p = njs_string_alloc(vm, &vm->retval, length, 0);
+ if (nxt_slow_path(p == NULL)) {
+ return NJS_ERROR;
+ }
+
+ octet = array->start;
+
+ while (length != 0) {
+ *p++ = (u_char) njs_number_to_integer(octet->data.u.number);
+ octet++;
+ length--;
+ }
+
+ return NJS_OK;
+}
+
+
+static njs_ret_t
+njs_string_bytes_from_string(njs_vm_t *vm, const njs_value_t *args,
+ nxt_uint_t nargs)
+{
+ nxt_str_t enc, str;
+ const njs_value_t *enc_val;
+
+ enc_val = njs_arg(args, nargs, 2);
+
+ if (nxt_slow_path(nargs > 1 && !njs_is_string(enc_val))) {
+ njs_type_error(vm, "encoding must be a string");
+ return NJS_ERROR;
+ }
+
+ njs_string_get(enc_val, &enc);
+ njs_string_get(&args[1], &str);
+
+ if (enc.length == 3 && memcmp(enc.start, "hex", 3) == 0) {
+ return njs_string_decode_hex(vm, &vm->retval, &str);
+
+ } else if (enc.length == 6 && memcmp(enc.start, "base64", 6) == 0) {
+ return njs_string_decode_base64(vm, &vm->retval, &str);
+
+ } else if (enc.length == 9 && memcmp(enc.start, "base64url", 6) == 0) {
+ return njs_string_decode_base64url(vm, &vm->retval, &str);
+ }
+
+ njs_type_error(vm, "Unknown encoding: '%.*s'", (int) enc.length,
+ enc.start);
+
+ return NJS_ERROR;
+}
+
+
+nxt_noinline njs_ret_t
+njs_string_decode_hex(njs_vm_t *vm, njs_value_t *value, const nxt_str_t *src)
+{
+ u_char *p, *dst;
+ size_t len;
+ nxt_int_t c;
+ nxt_uint_t i, n;
+ const u_char *start;
+
+ len = src->length;
+ start = src->start;
+
+ if (nxt_slow_path(len == 0)) {
+ vm->retval = njs_string_empty;
+ return NJS_OK;
+ }
+
+ dst = njs_string_alloc(vm, value, len / 2, 0);
+ if (nxt_slow_path(dst == NULL)) {
+ return NJS_ERROR;
+ }
+
+ n = 0;
+ p = dst;
+
+ for (i = 0; i < len; i++) {
+ c = njs_char_to_hex(start[i]);
+ if (nxt_slow_path(c < 0)) {
+ break;
+ }
+
+ n = n * 16 + c;
+
+ if ((i & 1) != 0) {
+ *p++ = (u_char) n;
+ n = 0;
+ }
+ }
+
+ if (nxt_slow_path((size_t) (p - dst) != (len / 2))) {
+ njs_string_truncate(value, p - dst);
+ }
+
+ return NJS_OK;
+}
+
+
+nxt_noinline njs_ret_t
+njs_string_decode_base64(njs_vm_t *vm, njs_value_t *value, const nxt_str_t *src)
+{
+ static u_char basis64[] = {
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 62, 77, 77, 77, 63,
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 77, 77, 77, 77, 77, 77,
+ 77, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 77, 77, 77, 77, 77,
+ 77, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 77, 77, 77, 77, 77,
+
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77
+ };
+
+ return njs_decode_base64_core(vm, value, src, basis64);
+}
+
+
+nxt_noinline njs_ret_t
+njs_string_decode_base64url(njs_vm_t *vm, njs_value_t *value,
+ const nxt_str_t *src)
+{
+ static u_char basis64[] = {
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 62, 77, 77,
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 77, 77, 77, 77, 77, 77,
+ 77, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 77, 77, 77, 77, 63,
+ 77, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 77, 77, 77, 77, 77,
+
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77,
+ 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77, 77
+ };
+
+ return njs_decode_base64_core(vm, value, src, basis64);
+}
+
+
+static njs_ret_t
+njs_decode_base64_core(njs_vm_t *vm, njs_value_t *value, const nxt_str_t *src,
+ const u_char *basis)
+{
+ size_t len, dst_len;
+ u_char *d, *s, *dst;
+
+ if (nxt_slow_path(src->length == 0)) {
+ vm->retval = njs_string_empty;
+ return NJS_OK;
+ }
+
+ for (len = 0; len < src->length; len++) {
+ if (src->start[len] == '=') {
+ break;
+ }
+
+ if (basis[src->start[len]] == 77) {
+ break;
+ }
+ }
+
+ if (len % 4 == 1) {
+ /* Rounding down to integer multiple of 4. */
+ len -= 1;
+ }
+
+ dst_len = njs_base64_decoded_length(len);
+
+ dst = njs_string_alloc(vm, value, dst_len, 0);
+ if (nxt_slow_path(dst == NULL)) {
+ return NJS_ERROR;
+ }
+
+ s = src->start;
+ d = dst;
+
+ while (len > 3) {
+ *d++ = (u_char) (basis[s[0]] << 2 | basis[s[1]] >> 4);
+ *d++ = (u_char) (basis[s[1]] << 4 | basis[s[2]] >> 2);
+ *d++ = (u_char) (basis[s[2]] << 6 | basis[s[3]]);
+
+ s += 4;
+ len -= 4;
+ }
+
+ if (len > 1) {
+ *d++ = (u_char) (basis[s[0]] << 2 | basis[s[1]] >> 4);
+ }
+
+ if (len > 2) {
+ *d++ = (u_char) (basis[s[1]] << 4 | basis[s[2]] >> 2);
+ }
+
+ if (nxt_slow_path((size_t) (d - dst) != dst_len)) {
+ njs_string_truncate(value, d - dst);
+ }
+
+ return NXT_OK;
+}
+
+
static njs_ret_t
njs_string_from_char_code(njs_vm_t *vm, njs_value_t *args,
nxt_uint_t nargs, njs_index_t unused)
diff -r 729072cc162f -r 9322e8eab0b6 njs/njs_string.h
--- a/njs/njs_string.h Tue Jul 17 20:25:47 2018 +0300
+++ b/njs/njs_string.h Wed Jul 18 15:41:55 2018 +0300
@@ -129,6 +129,13 @@ njs_ret_t njs_string_base64(njs_vm_t *vm
const nxt_str_t *src);
njs_ret_t njs_string_base64url(njs_vm_t *vm, njs_value_t *value,
const nxt_str_t *src);
+njs_ret_t njs_string_decode_hex(njs_vm_t *vm, njs_value_t *value,
+ const nxt_str_t *src);
+njs_ret_t njs_string_decode_base64(njs_vm_t *vm, njs_value_t *value,
+ const nxt_str_t *src);
+njs_ret_t njs_string_decode_base64url(njs_vm_t *vm, njs_value_t *value,
+ const nxt_str_t *src);
+void njs_string_truncate(njs_value_t *value, uint32_t size);
void njs_string_copy(njs_value_t *dst, njs_value_t *src);
njs_ret_t njs_string_validate(njs_vm_t *vm, njs_string_prop_t *string,
njs_value_t *value);
diff -r 729072cc162f -r 9322e8eab0b6 njs/test/njs_unit_test.c
--- a/njs/test/njs_unit_test.c Tue Jul 17 20:25:47 2018 +0300
+++ b/njs/test/njs_unit_test.c Wed Jul 18 15:41:55 2018 +0300
@@ -4656,6 +4656,69 @@ static njs_unit_test_t njs_test[] =
{ nxt_string("'абвг'.padEnd(10, 'ДЕЖЗ')"),
nxt_string("абвгДЕЖЗДЕ") },

+ { nxt_string("String.bytesFrom({})"),
+ nxt_string("TypeError: value must be a string or array") },
+
+ { nxt_string("String.bytesFrom([1, 2, 0.23, '5', 'A']).toString('hex')"),
+ nxt_string("0102000500") },
+
+ { nxt_string("String.bytesFrom([NaN, Infinity]).toString('hex')"),
+ nxt_string("0000") },
+
+ { nxt_string("String.bytesFrom('', 'hex')"),
+ nxt_string("") },
+
+ { nxt_string("String.bytesFrom('00aabbcc', 'hex').toString('hex')"),
+ nxt_string("00aabbcc") },
+
+ { nxt_string("String.bytesFrom('deadBEEF##', 'hex').toString('hex')"),
+ nxt_string("deadbeef") },
+
+ { nxt_string("String.bytesFrom('aa0', 'hex').toString('hex')"),
+ nxt_string("aa") },
+
+ { nxt_string("String.bytesFrom('', 'base64')"),
+ nxt_string("") },
+
+ { nxt_string("String.bytesFrom('#', 'base64')"),
+ nxt_string("") },
+
+ { nxt_string("String.bytesFrom('QQ==', 'base64')"),
+ nxt_string("A") },
+
+ { nxt_string("String.bytesFrom('QQ', 'base64')"),
+ nxt_string("A") },
+
+ { nxt_string("String.bytesFrom('QUI=', 'base64')"),
+ nxt_string("AB") },
+
+ { nxt_string("String.bytesFrom('QUI', 'base64')"),
+ nxt_string("AB") },
+
+ { nxt_string("String.bytesFrom('QUJD', 'base64')"),
+ nxt_string("ABC") },
+
+ { nxt_string("String.bytesFrom('QUJDRA==', 'base64')"),
+ nxt_string("ABCD") },
+
+ { nxt_string("String.bytesFrom('', 'base64url')"),
+ nxt_string("") },
+
+ { nxt_string("String.bytesFrom('QQ', 'base64url')"),
+ nxt_string("A") },
+
+ { nxt_string("String.bytesFrom('QUI', 'base64url')"),
+ nxt_string("AB") },
+
+ { nxt_string("String.bytesFrom('QUJD', 'base64url')"),
+ nxt_string("ABC") },
+
+ { nxt_string("String.bytesFrom('QUJDRA', 'base64url')"),
+ nxt_string("ABCD") },
+
+ { nxt_string("String.bytesFrom('QUJDRA#', 'base64url')"),
+ nxt_string("ABCD") },
+
{ nxt_string("encodeURI()"),
nxt_string("undefined")},

_______________________________________________
nginx-devel mailing list
nginx-devel@nginx.org
http://mailman.nginx.org/mailman/listinfo/nginx-devel
Subject Author Views Posted

[njs] String.bytesFrom() method.

Dmitry Volyntsev 758 July 18, 2018 08:44AM



Sorry, you do not have permission to post/reply in this forum.

Online Users

Guests: 236
Record Number of Users: 8 on April 13, 2023
Record Number of Guests: 421 on December 02, 2018
Powered by nginx      Powered by FreeBSD      PHP Powered      Powered by MariaDB      ipv6 ready