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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 08:06:26 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 08:06:26 +0000
commit1660d4b7a65d9ad2ce0deaa19d35579ca4084ac5 (patch)
tree6cf8220b628ebd2ccfc1375dd6516c6996e9abcc /lib/crypto_backend/utf8.c
parentInitial commit. (diff)
downloadcryptsetup-1660d4b7a65d9ad2ce0deaa19d35579ca4084ac5.tar.xz
cryptsetup-1660d4b7a65d9ad2ce0deaa19d35579ca4084ac5.zip
Adding upstream version 2:2.6.1.upstream/2%2.6.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/crypto_backend/utf8.c')
-rw-r--r--lib/crypto_backend/utf8.c288
1 files changed, 288 insertions, 0 deletions
diff --git a/lib/crypto_backend/utf8.c b/lib/crypto_backend/utf8.c
new file mode 100644
index 0000000..24e0d8d
--- /dev/null
+++ b/lib/crypto_backend/utf8.c
@@ -0,0 +1,288 @@
+/*
+ * UTF8/16 helpers, copied and adapted from systemd project.
+ *
+ * Copyright (C) 2010 Lennart Poettering
+ *
+ * cryptsetup related changes
+ * Copyright (C) 2021-2023 Vojtech Trefny
+
+ * Parts of the original systemd implementation are based on the GLIB utf8
+ * validation functions.
+ * gutf8.c - Operations on UTF-8 strings.
+ *
+ * Copyright (C) 1999 Tom Tromey
+ * Copyright (C) 2000 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <errno.h>
+#include <endian.h>
+
+#include "crypto_backend.h"
+
+static inline bool utf16_is_surrogate(char16_t c)
+{
+ return c >= 0xd800U && c <= 0xdfffU;
+}
+
+static inline bool utf16_is_trailing_surrogate(char16_t c)
+{
+ return c >= 0xdc00U && c <= 0xdfffU;
+}
+
+static inline char32_t utf16_surrogate_pair_to_unichar(char16_t lead, char16_t trail)
+{
+ return ((((char32_t) lead - 0xd800U) << 10) + ((char32_t) trail - 0xdc00U) + 0x10000U);
+}
+
+/**
+ * utf8_encode_unichar() - Encode single UCS-4 character as UTF-8
+ * @out_utf8: output buffer of at least 4 bytes or NULL
+ * @g: UCS-4 character to encode
+ *
+ * This encodes a single UCS-4 character as UTF-8 and writes it into @out_utf8.
+ * The length of the character is returned. It is not zero-terminated! If the
+ * output buffer is NULL, only the length is returned.
+ *
+ * Returns: The length in bytes that the UTF-8 representation does or would
+ * occupy.
+ */
+static size_t utf8_encode_unichar(char *out_utf8, char32_t g)
+{
+ if (g < (1 << 7)) {
+ if (out_utf8)
+ out_utf8[0] = g & 0x7f;
+ return 1;
+ } else if (g < (1 << 11)) {
+ if (out_utf8) {
+ out_utf8[0] = 0xc0 | ((g >> 6) & 0x1f);
+ out_utf8[1] = 0x80 | (g & 0x3f);
+ }
+ return 2;
+ } else if (g < (1 << 16)) {
+ if (out_utf8) {
+ out_utf8[0] = 0xe0 | ((g >> 12) & 0x0f);
+ out_utf8[1] = 0x80 | ((g >> 6) & 0x3f);
+ out_utf8[2] = 0x80 | (g & 0x3f);
+ }
+ return 3;
+ } else if (g < (1 << 21)) {
+ if (out_utf8) {
+ out_utf8[0] = 0xf0 | ((g >> 18) & 0x07);
+ out_utf8[1] = 0x80 | ((g >> 12) & 0x3f);
+ out_utf8[2] = 0x80 | ((g >> 6) & 0x3f);
+ out_utf8[3] = 0x80 | (g & 0x3f);
+ }
+ return 4;
+ }
+
+ return 0;
+}
+
+/**
+ * crypt_utf16_to_utf8()
+ * @out: output buffer, should be 2 * @length + 1 long
+ * @s: string to convert
+ * @length: length of @s in bytes
+ *
+ * Converts a UTF16LE encoded string to a UTF8 encoded string.
+ *
+ * Returns: 0 on success, negative errno otherwise
+ */
+int crypt_utf16_to_utf8(char **out, const char16_t *s, size_t length /* bytes! */)
+{
+ const uint8_t *f;
+ char *t;
+
+ assert(s);
+ assert(out);
+ assert(*out);
+
+ /* Input length is in bytes, i.e. the shortest possible character takes 2 bytes. Each unicode character may
+ * take up to 4 bytes in UTF-8. Let's also account for a trailing NUL byte. */
+ if (length * 2 < length)
+ return -EOVERFLOW; /* overflow */
+
+ f = (const uint8_t*) s;
+ t = *out;
+
+ while (f + 1 < (const uint8_t*) s + length) {
+ char16_t w1, w2;
+
+ /* see RFC 2781 section 2.2 */
+
+ w1 = f[1] << 8 | f[0];
+ f += 2;
+
+ if (!utf16_is_surrogate(w1)) {
+ t += utf8_encode_unichar(t, w1);
+ continue;
+ }
+
+ if (utf16_is_trailing_surrogate(w1))
+ continue; /* spurious trailing surrogate, ignore */
+
+ if (f + 1 >= (const uint8_t*) s + length)
+ break;
+
+ w2 = f[1] << 8 | f[0];
+ f += 2;
+
+ if (!utf16_is_trailing_surrogate(w2)) {
+ f -= 2;
+ continue; /* surrogate missing its trailing surrogate, ignore */
+ }
+
+ t += utf8_encode_unichar(t, utf16_surrogate_pair_to_unichar(w1, w2));
+ }
+
+ *t = 0;
+ return 0;
+}
+
+/* count of characters used to encode one unicode char */
+static size_t utf8_encoded_expected_len(uint8_t c)
+{
+ if (c < 0x80)
+ return 1;
+ if ((c & 0xe0) == 0xc0)
+ return 2;
+ if ((c & 0xf0) == 0xe0)
+ return 3;
+ if ((c & 0xf8) == 0xf0)
+ return 4;
+ if ((c & 0xfc) == 0xf8)
+ return 5;
+ if ((c & 0xfe) == 0xfc)
+ return 6;
+
+ return 0;
+}
+
+/* decode one unicode char */
+static int utf8_encoded_to_unichar(const char *str, char32_t *ret_unichar)
+{
+ char32_t unichar;
+ size_t len, i;
+
+ assert(str);
+
+ len = utf8_encoded_expected_len(str[0]);
+
+ switch (len) {
+ case 1:
+ *ret_unichar = (char32_t)str[0];
+ return 0;
+ case 2:
+ unichar = str[0] & 0x1f;
+ break;
+ case 3:
+ unichar = (char32_t)str[0] & 0x0f;
+ break;
+ case 4:
+ unichar = (char32_t)str[0] & 0x07;
+ break;
+ case 5:
+ unichar = (char32_t)str[0] & 0x03;
+ break;
+ case 6:
+ unichar = (char32_t)str[0] & 0x01;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ for (i = 1; i < len; i++) {
+ if (((char32_t)str[i] & 0xc0) != 0x80)
+ return -EINVAL;
+
+ unichar <<= 6;
+ unichar |= (char32_t)str[i] & 0x3f;
+ }
+
+ *ret_unichar = unichar;
+
+ return 0;
+}
+
+static size_t utf16_encode_unichar(char16_t *out, char32_t c)
+{
+ /* Note that this encodes as little-endian. */
+
+ switch (c) {
+
+ case 0 ... 0xd7ffU:
+ case 0xe000U ... 0xffffU:
+ out[0] = htole16(c);
+ return 1;
+
+ case 0x10000U ... 0x10ffffU:
+ c -= 0x10000U;
+ out[0] = htole16((c >> 10) + 0xd800U);
+ out[1] = htole16((c & 0x3ffU) + 0xdc00U);
+ return 2;
+
+ default: /* A surrogate (invalid) */
+ return 0;
+ }
+}
+
+/**
+ * crypt_utf8_to_utf16()
+ * @out: output buffer, should be @length + 1 long
+ * @s: string to convert
+ * @length: length of @s in bytes
+ *
+ * Converts a UTF8 encoded string to a UTF16LE encoded string.
+ *
+ * Returns: 0 on success, negative errno otherwise
+ */
+int crypt_utf8_to_utf16(char16_t **out, const char *s, size_t length)
+{
+ char16_t *p;
+ size_t i;
+ int r;
+
+ assert(s);
+
+ p = *out;
+
+ for (i = 0; i < length;) {
+ char32_t unichar;
+ size_t e;
+
+ e = utf8_encoded_expected_len(s[i]);
+ if (e <= 1) /* Invalid and single byte characters are copied as they are */
+ goto copy;
+
+ if (i + e > length) /* sequence longer than input buffer, then copy as-is */
+ goto copy;
+
+ r = utf8_encoded_to_unichar(s + i, &unichar);
+ if (r < 0) /* sequence invalid, then copy as-is */
+ goto copy;
+
+ p += utf16_encode_unichar(p, unichar);
+ i += e;
+ continue;
+
+ copy:
+ *(p++) = htole16(s[i++]);
+ }
+
+ *p = 0;
+ return 0;
+}