diff options
Diffstat (limited to 'src/shared')
| -rw-r--r-- | src/shared/utf8.c | 151 | ||||
| -rw-r--r-- | src/shared/utf8.h | 4 |
2 files changed, 155 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; +} diff --git a/src/shared/utf8.h b/src/shared/utf8.h index f805ea6b59..7a5608c9ee 100644 --- a/src/shared/utf8.h +++ b/src/shared/utf8.h @@ -34,3 +34,7 @@ char *utf8_filter(const char *s); char *ascii_filter(const char *s); char *utf16_to_utf8(const void *s, size_t length); + +int utf8_encoded_valid_unichar(const char *str); +int is_utf8_encoding_whitelisted(char c, const char *white); +int udev_encode_string(const char *str, char *str_enc, size_t len); |