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-rw-r--r--src/shared/utf8.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/src/shared/utf8.c b/src/shared/utf8.c
index 655cc771d4..1a68394a53 100644
--- a/src/shared/utf8.c
+++ b/src/shared/utf8.c
@@ -317,3 +317,154 @@ char *utf16_to_utf8(const void *s, size_t length) {
return r;
}
+
+/* count of characters used to encode one unicode char */
+static int utf8_encoded_expected_len(const char *str) {
+ unsigned char c = (unsigned char)str[0];
+
+ 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) {
+ int unichar;
+ int len;
+ int i;
+
+ len = utf8_encoded_expected_len(str);
+ switch (len) {
+ case 1:
+ return (int)str[0];
+ case 2:
+ unichar = str[0] & 0x1f;
+ break;
+ case 3:
+ unichar = (int)str[0] & 0x0f;
+ break;
+ case 4:
+ unichar = (int)str[0] & 0x07;
+ break;
+ case 5:
+ unichar = (int)str[0] & 0x03;
+ break;
+ case 6:
+ unichar = (int)str[0] & 0x01;
+ break;
+ default:
+ return -1;
+ }
+
+ for (i = 1; i < len; i++) {
+ if (((int)str[i] & 0xc0) != 0x80)
+ return -1;
+ unichar <<= 6;
+ unichar |= (int)str[i] & 0x3f;
+ }
+
+ return unichar;
+}
+
+/* expected size used to encode one unicode char */
+static int utf8_unichar_to_encoded_len(int unichar) {
+ if (unichar < 0x80)
+ return 1;
+ if (unichar < 0x800)
+ return 2;
+ if (unichar < 0x10000)
+ return 3;
+ if (unichar < 0x200000)
+ return 4;
+ if (unichar < 0x4000000)
+ return 5;
+ return 6;
+}
+
+/* validate one encoded unicode char and return its length */
+int utf8_encoded_valid_unichar(const char *str) {
+ int len;
+ int unichar;
+ int i;
+
+ len = utf8_encoded_expected_len(str);
+ if (len == 0)
+ return -1;
+
+ /* ascii is valid */
+ if (len == 1)
+ return 1;
+
+ /* check if expected encoded chars are available */
+ for (i = 0; i < len; i++)
+ if ((str[i] & 0x80) != 0x80)
+ return -1;
+
+ unichar = utf8_encoded_to_unichar(str);
+
+ /* check if encoded length matches encoded value */
+ if (utf8_unichar_to_encoded_len(unichar) != len)
+ return -1;
+
+ /* check if value has valid range */
+ if (!is_unicode_valid(unichar))
+ return -1;
+
+ return len;
+}
+
+int is_utf8_encoding_whitelisted(char c, const char *white) {
+ if ((c >= '0' && c <= '9') ||
+ (c >= 'A' && c <= 'Z') ||
+ (c >= 'a' && c <= 'z') ||
+ strchr("#+-.:=@_", c) != NULL ||
+ (white != NULL && strchr(white, c) != NULL))
+ return 1;
+ return 0;
+}
+
+int udev_encode_string(const char *str, char *str_enc, size_t len) {
+ size_t i, j;
+
+ if (str == NULL || str_enc == NULL)
+ return -1;
+
+ for (i = 0, j = 0; str[i] != '\0'; i++) {
+ int seqlen;
+
+ seqlen = utf8_encoded_valid_unichar(&str[i]);
+ if (seqlen > 1) {
+ if (len-j < (size_t)seqlen)
+ goto err;
+ memcpy(&str_enc[j], &str[i], seqlen);
+ j += seqlen;
+ i += (seqlen-1);
+ } else if (str[i] == '\\' || !is_utf8_encoding_whitelisted(str[i], NULL)) {
+ if (len-j < 4)
+ goto err;
+ sprintf(&str_enc[j], "\\x%02x", (unsigned char) str[i]);
+ j += 4;
+ } else {
+ if (len-j < 1)
+ goto err;
+ str_enc[j] = str[i];
+ j++;
+ }
+ }
+ if (len-j < 1)
+ goto err;
+ str_enc[j] = '\0';
+ return 0;
+err:
+ return -1;
+}