/* * MIT License * * Copyright (c) 2019 Yibo Cai * Copyright (c) 2019 Vsevolod Stakhov * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "config.h" #include "fastutf8.h" #include "platform_config.h" #ifndef __clang__ #pragma GCC push_options #pragma GCC target("sse4.1") #endif #ifndef __SSE2__ #define __SSE2__ #endif #ifndef __SSE__ #define __SSE__ #endif #ifndef __SSEE3__ #define __SSEE3__ #endif #ifndef __SSE4_1__ #define __SSE4_1__ #endif #include /* * Map high nibble of "First Byte" to legal character length minus 1 * 0x00 ~ 0xBF --> 0 * 0xC0 ~ 0xDF --> 1 * 0xE0 ~ 0xEF --> 2 * 0xF0 ~ 0xFF --> 3 */ static const int8_t _first_len_tbl[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 3, }; /* Map "First Byte" to 8-th item of range table (0xC2 ~ 0xF4) */ static const int8_t _first_range_tbl[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8, }; /* * Range table, map range index to min and max values * Index 0 : 00 ~ 7F (First Byte, ascii) * Index 1,2,3: 80 ~ BF (Second, Third, Fourth Byte) * Index 4 : A0 ~ BF (Second Byte after E0) * Index 5 : 80 ~ 9F (Second Byte after ED) * Index 6 : 90 ~ BF (Second Byte after F0) * Index 7 : 80 ~ 8F (Second Byte after F4) * Index 8 : C2 ~ F4 (First Byte, non ascii) * Index 9~15 : illegal: i >= 127 && i <= -128 */ static const int8_t _range_min_tbl[] = { 0x00, 0x80, 0x80, 0x80, 0xA0, 0x80, 0x90, 0x80, 0xC2, 0x7F, 0x7F, 0x7F, 0x7F, 0x7F, 0x7F, 0x7F, }; static const int8_t _range_max_tbl[] = { 0x7F, 0xBF, 0xBF, 0xBF, 0xBF, 0x9F, 0xBF, 0x8F, 0xF4, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, }; /* * Tables for fast handling of four special First Bytes(E0,ED,F0,F4), after * which the Second Byte are not 80~BF. It contains "range index adjustment". * +------------+---------------+------------------+----------------+ * | First Byte | original range| range adjustment | adjusted range | * +------------+---------------+------------------+----------------+ * | E0 | 2 | 2 | 4 | * +------------+---------------+------------------+----------------+ * | ED | 2 | 3 | 5 | * +------------+---------------+------------------+----------------+ * | F0 | 3 | 3 | 6 | * +------------+---------------+------------------+----------------+ * | F4 | 4 | 4 | 8 | * +------------+---------------+------------------+----------------+ */ /* index1 -> E0, index14 -> ED */ static const int8_t _df_ee_tbl[] = { 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, }; /* index1 -> F0, index5 -> F4 */ static const int8_t _ef_fe_tbl[] = { 0, 3, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }; off_t rspamd_fast_utf8_validate_sse41 (const unsigned char *data, size_t len) __attribute__((__target__("sse4.1"))); /* Return 0 - success, >0 - first error char(if RET_ERR_IDX = 1) */ off_t rspamd_fast_utf8_validate_sse41 (const unsigned char *data, size_t len) { off_t err_pos = 1; if (len >= 16) { __m128i prev_input = _mm_set1_epi8 (0); __m128i prev_first_len = _mm_set1_epi8 (0); /* Cached tables */ const __m128i first_len_tbl = _mm_lddqu_si128 ((const __m128i *) _first_len_tbl); const __m128i first_range_tbl = _mm_lddqu_si128 ((const __m128i *) _first_range_tbl); const __m128i range_min_tbl = _mm_lddqu_si128 ((const __m128i *) _range_min_tbl); const __m128i range_max_tbl = _mm_lddqu_si128 ((const __m128i *) _range_max_tbl); const __m128i df_ee_tbl = _mm_lddqu_si128 ((const __m128i *) _df_ee_tbl); const __m128i ef_fe_tbl = _mm_lddqu_si128 ((const __m128i *) _ef_fe_tbl); __m128i error = _mm_set1_epi8 (0); while (len >= 16) { const __m128i input = _mm_lddqu_si128 ((const __m128i *) data); /* high_nibbles = input >> 4 */ const __m128i high_nibbles = _mm_and_si128 (_mm_srli_epi16 (input, 4), _mm_set1_epi8 (0x0F)); /* first_len = legal character length minus 1 */ /* 0 for 00~7F, 1 for C0~DF, 2 for E0~EF, 3 for F0~FF */ /* first_len = first_len_tbl[high_nibbles] */ __m128i first_len = _mm_shuffle_epi8 (first_len_tbl, high_nibbles); /* First Byte: set range index to 8 for bytes within 0xC0 ~ 0xFF */ /* range = first_range_tbl[high_nibbles] */ __m128i range = _mm_shuffle_epi8 (first_range_tbl, high_nibbles); /* Second Byte: set range index to first_len */ /* 0 for 00~7F, 1 for C0~DF, 2 for E0~EF, 3 for F0~FF */ /* range |= (first_len, prev_first_len) << 1 byte */ range = _mm_or_si128 ( range, _mm_alignr_epi8(first_len, prev_first_len, 15)); /* Third Byte: set range index to saturate_sub(first_len, 1) */ /* 0 for 00~7F, 0 for C0~DF, 1 for E0~EF, 2 for F0~FF */ __m128i tmp1, tmp2; /* tmp1 = saturate_sub(first_len, 1) */ tmp1 = _mm_subs_epu8 (first_len, _mm_set1_epi8 (1)); /* tmp2 = saturate_sub(prev_first_len, 1) */ tmp2 = _mm_subs_epu8 (prev_first_len, _mm_set1_epi8 (1)); /* range |= (tmp1, tmp2) << 2 bytes */ range = _mm_or_si128 (range, _mm_alignr_epi8(tmp1, tmp2, 14)); /* Fourth Byte: set range index to saturate_sub(first_len, 2) */ /* 0 for 00~7F, 0 for C0~DF, 0 for E0~EF, 1 for F0~FF */ /* tmp1 = saturate_sub(first_len, 2) */ tmp1 = _mm_subs_epu8 (first_len, _mm_set1_epi8 (2)); /* tmp2 = saturate_sub(prev_first_len, 2) */ tmp2 = _mm_subs_epu8 (prev_first_len, _mm_set1_epi8 (2)); /* range |= (tmp1, tmp2) << 3 bytes */ range = _mm_or_si128 (range, _mm_alignr_epi8(tmp1, tmp2, 13)); /* * Now we have below range indices caluclated * Correct cases: * - 8 for C0~FF * - 3 for 1st byte after F0~FF * - 2 for 1st byte after E0~EF or 2nd byte after F0~FF * - 1 for 1st byte after C0~DF or 2nd byte after E0~EF or * 3rd byte after F0~FF * - 0 for others * Error cases: * 9,10,11 if non ascii First Byte overlaps * E.g., F1 80 C2 90 --> 8 3 10 2, where 10 indicates error */ /* Adjust Second Byte range for special First Bytes(E0,ED,F0,F4) */ /* Overlaps lead to index 9~15, which are illegal in range table */ __m128i shift1, pos, range2; /* shift1 = (input, prev_input) << 1 byte */ shift1 = _mm_alignr_epi8(input, prev_input, 15); pos = _mm_sub_epi8 (shift1, _mm_set1_epi8 (0xEF)); /* * shift1: | EF F0 ... FE | FF 00 ... ... DE | DF E0 ... EE | * pos: | 0 1 15 | 16 17 239| 240 241 255| * pos-240: | 0 0 0 | 0 0 0 | 0 1 15 | * pos+112: | 112 113 127| >= 128 | >= 128 | */ tmp1 = _mm_subs_epu8 (pos, _mm_set1_epi8 ((char)240)); range2 = _mm_shuffle_epi8 (df_ee_tbl, tmp1); tmp2 = _mm_adds_epu8 (pos, _mm_set1_epi8 (112)); range2 = _mm_add_epi8 (range2, _mm_shuffle_epi8 (ef_fe_tbl, tmp2)); range = _mm_add_epi8 (range, range2); /* Load min and max values per calculated range index */ __m128i minv = _mm_shuffle_epi8 (range_min_tbl, range); __m128i maxv = _mm_shuffle_epi8 (range_max_tbl, range); /* Check value range */ error = _mm_cmplt_epi8(input, minv); error = _mm_or_si128(error, _mm_cmpgt_epi8(input, maxv)); /* 5% performance drop from this conditional branch */ if (!_mm_testz_si128(error, error)) { break; } prev_input = input; prev_first_len = first_len; data += 16; len -= 16; err_pos += 16; } /* Error in first 16 bytes */ if (err_pos == 1) { goto do_naive; } /* Find previous token (not 80~BF) */ int32_t token4 = _mm_extract_epi32 (prev_input, 3); const int8_t *token = (const int8_t *) &token4; int lookahead = 0; if (token[3] > (int8_t) 0xBF) { lookahead = 1; } else if (token[2] > (int8_t) 0xBF) { lookahead = 2; } else if (token[1] > (int8_t) 0xBF) { lookahead = 3; } data -= lookahead; len += lookahead; err_pos -= lookahead; } do_naive: if (len > 0) { off_t err_pos2 = rspamd_fast_utf8_validate_ref (data, len); if (err_pos2) { return err_pos + err_pos2 - 1; } } return 0; } #ifndef __clang__ #pragma GCC pop_options #endif