/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2008-2011 Kay Sievers Copyright 2012 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ /* Parts of this file are based on the GLIB utf8 validation functions. The * original license text follows. */ /* 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 <stdlib.h> #include <inttypes.h> #include <string.h> #include <stdbool.h> #include "utf8.h" #include "util.h" static inline bool is_unicode_valid(uint32_t ch) { if (ch >= 0x110000) /* End of unicode space */ return false; if ((ch & 0xFFFFF800) == 0xD800) /* Reserved area for UTF-16 */ return false; if ((ch >= 0xFDD0) && (ch <= 0xFDEF)) /* Reserved */ return false; if ((ch & 0xFFFE) == 0xFFFE) /* BOM (Byte Order Mark) */ return false; return true; } static bool is_unicode_control(uint32_t ch) { /* 0 to ' '-1 is the C0 range. DEL=0x7F, and DEL+1 to 0x9F is C1 range. '\t' is in C0 range, but more or less harmless and commonly used. */ return (ch < ' ' && ch != '\t' && ch != '\n') || (0x7F <= ch && ch <= 0x9F); } /* count of characters used to encode one unicode char */ static int utf8_encoded_expected_len(const char *str) { unsigned char c; assert(str); 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 */ int utf8_encoded_to_unichar(const char *str) { int unichar, len, i; assert(str); 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 -EINVAL; } for (i = 1; i < len; i++) { if (((int)str[i] & 0xc0) != 0x80) return -EINVAL; unichar <<= 6; unichar |= (int)str[i] & 0x3f; } return unichar; } bool utf8_is_printable_newline(const char* str, size_t length, bool newline) { const uint8_t *p; assert(str); for (p = (const uint8_t*) str; length;) { int encoded_len, val; encoded_len = utf8_encoded_valid_unichar((const char *) p); val = utf8_encoded_to_unichar((const char*) p); if (encoded_len < 0 || val < 0 || is_unicode_control(val) || (!newline && val == '\n')) return false; length -= encoded_len; p += encoded_len; } return true; } const char *utf8_is_valid(const char *str) { const uint8_t *p; assert(str); for (p = (const uint8_t*) str; *p; ) { int len; len = utf8_encoded_valid_unichar((const char *)p); if (len < 0) return NULL; p += len; } return str; } char *utf8_escape_invalid(const char *str) { char *p, *s; assert(str); p = s = malloc(strlen(str) * 4 + 1); if (!p) return NULL; while (*str) { int len; len = utf8_encoded_valid_unichar(str); if (len > 0) { s = mempcpy(s, str, len); str += len; } else { s = mempcpy(s, UTF8_REPLACEMENT_CHARACTER, strlen(UTF8_REPLACEMENT_CHARACTER)); str += 1; } } *s = '\0'; return p; } char *ascii_is_valid(const char *str) { const char *p; assert(str); for (p = str; *p; p++) if ((unsigned char) *p >= 128) return NULL; return (char*) str; } char *utf16_to_utf8(const void *s, size_t length) { char *r; const uint8_t *f; uint8_t *t; r = new(char, (length*3+1)/2 + 1); if (!r) return NULL; t = (uint8_t*) r; for (f = s; f < (const uint8_t*) s + length; f += 2) { uint16_t c; c = (f[1] << 8) | f[0]; if (c == 0) { *t = 0; return r; } else if (c < 0x80) { *(t++) = (uint8_t) c; } else if (c < 0x800) { *(t++) = (uint8_t) (0xc0 | (c >> 6)); *(t++) = (uint8_t) (0x80 | (c & 0x3f)); } else { *(t++) = (uint8_t) (0xe0 | (c >> 12)); *(t++) = (uint8_t) (0x80 | ((c >> 6) & 0x3f)); *(t++) = (uint8_t) (0x80 | (c & 0x3f)); } } *t = 0; return r; } /* 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, unichar, i; assert(str); len = utf8_encoded_expected_len(str); if (len == 0) return -EINVAL; /* 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 -EINVAL; unichar = utf8_encoded_to_unichar(str); /* check if encoded length matches encoded value */ if (utf8_unichar_to_encoded_len(unichar) != len) return -EINVAL; /* check if value has valid range */ if (!is_unicode_valid(unichar)) return -EINVAL; return len; }