/* * Copyright (c) 2024 Nordic Semiconductor ASA * * SPDX-License-Identifier: Apache-2.0 */ #include #include #include #include #include LOG_MODULE_DECLARE(net_http_server, CONFIG_NET_HTTP_SERVER_LOG_LEVEL); struct decode_elem { uint8_t bitlen; uint8_t symbol; uint8_t code[4]; }; static const struct decode_elem decode_table[] = { { 5, 48, { 0b00000000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 49, { 0b00001000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 50, { 0b00010000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 97, { 0b00011000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 99, { 0b00100000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 101, { 0b00101000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 105, { 0b00110000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 111, { 0b00111000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 115, { 0b01000000, 0b00000000, 0b00000000, 0b00000000 } }, { 5, 116, { 0b01001000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 32, { 0b01010000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 37, { 0b01010100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 45, { 0b01011000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 46, { 0b01011100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 47, { 0b01100000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 51, { 0b01100100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 52, { 0b01101000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 53, { 0b01101100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 54, { 0b01110000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 55, { 0b01110100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 56, { 0b01111000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 57, { 0b01111100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 61, { 0b10000000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 65, { 0b10000100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 95, { 0b10001000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 98, { 0b10001100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 100, { 0b10010000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 102, { 0b10010100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 103, { 0b10011000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 104, { 0b10011100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 108, { 0b10100000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 109, { 0b10100100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 110, { 0b10101000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 112, { 0b10101100, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 114, { 0b10110000, 0b00000000, 0b00000000, 0b00000000 } }, { 6, 117, { 0b10110100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 58, { 0b10111000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 66, { 0b10111010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 67, { 0b10111100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 68, { 0b10111110, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 69, { 0b11000000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 70, { 0b11000010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 71, { 0b11000100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 72, { 0b11000110, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 73, { 0b11001000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 74, { 0b11001010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 75, { 0b11001100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 76, { 0b11001110, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 77, { 0b11010000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 78, { 0b11010010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 79, { 0b11010100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 80, { 0b11010110, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 81, { 0b11011000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 82, { 0b11011010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 83, { 0b11011100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 84, { 0b11011110, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 85, { 0b11100000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 86, { 0b11100010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 87, { 0b11100100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 89, { 0b11100110, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 106, { 0b11101000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 107, { 0b11101010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 113, { 0b11101100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 118, { 0b11101110, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 119, { 0b11110000, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 120, { 0b11110010, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 121, { 0b11110100, 0b00000000, 0b00000000, 0b00000000 } }, { 7, 122, { 0b11110110, 0b00000000, 0b00000000, 0b00000000 } }, { 8, 38, { 0b11111000, 0b00000000, 0b00000000, 0b00000000 } }, { 8, 42, { 0b11111001, 0b00000000, 0b00000000, 0b00000000 } }, { 8, 44, { 0b11111010, 0b00000000, 0b00000000, 0b00000000 } }, { 8, 59, { 0b11111011, 0b00000000, 0b00000000, 0b00000000 } }, { 8, 88, { 0b11111100, 0b00000000, 0b00000000, 0b00000000 } }, { 8, 90, { 0b11111101, 0b00000000, 0b00000000, 0b00000000 } }, { 10, 33, { 0b11111110, 0b00000000, 0b00000000, 0b00000000 } }, { 10, 34, { 0b11111110, 0b01000000, 0b00000000, 0b00000000 } }, { 10, 40, { 0b11111110, 0b10000000, 0b00000000, 0b00000000 } }, { 10, 41, { 0b11111110, 0b11000000, 0b00000000, 0b00000000 } }, { 10, 63, { 0b11111111, 0b00000000, 0b00000000, 0b00000000 } }, { 11, 39, { 0b11111111, 0b01000000, 0b00000000, 0b00000000 } }, { 11, 43, { 0b11111111, 0b01100000, 0b00000000, 0b00000000 } }, { 11, 124, { 0b11111111, 0b10000000, 0b00000000, 0b00000000 } }, { 12, 35, { 0b11111111, 0b10100000, 0b00000000, 0b00000000 } }, { 12, 62, { 0b11111111, 0b10110000, 0b00000000, 0b00000000 } }, { 13, 0, { 0b11111111, 0b11000000, 0b00000000, 0b00000000 } }, { 13, 36, { 0b11111111, 0b11001000, 0b00000000, 0b00000000 } }, { 13, 64, { 0b11111111, 0b11010000, 0b00000000, 0b00000000 } }, { 13, 91, { 0b11111111, 0b11011000, 0b00000000, 0b00000000 } }, { 13, 93, { 0b11111111, 0b11100000, 0b00000000, 0b00000000 } }, { 13, 126, { 0b11111111, 0b11101000, 0b00000000, 0b00000000 } }, { 14, 94, { 0b11111111, 0b11110000, 0b00000000, 0b00000000 } }, { 14, 125, { 0b11111111, 0b11110100, 0b00000000, 0b00000000 } }, { 15, 60, { 0b11111111, 0b11111000, 0b00000000, 0b00000000 } }, { 15, 96, { 0b11111111, 0b11111010, 0b00000000, 0b00000000 } }, { 15, 123, { 0b11111111, 0b11111100, 0b00000000, 0b00000000 } }, { 19, 92, { 0b11111111, 0b11111110, 0b00000000, 0b00000000 } }, { 19, 195, { 0b11111111, 0b11111110, 0b00100000, 0b00000000 } }, { 19, 208, { 0b11111111, 0b11111110, 0b01000000, 0b00000000 } }, { 20, 128, { 0b11111111, 0b11111110, 0b01100000, 0b00000000 } }, { 20, 130, { 0b11111111, 0b11111110, 0b01110000, 0b00000000 } }, { 20, 131, { 0b11111111, 0b11111110, 0b10000000, 0b00000000 } }, { 20, 162, { 0b11111111, 0b11111110, 0b10010000, 0b00000000 } }, { 20, 184, { 0b11111111, 0b11111110, 0b10100000, 0b00000000 } }, { 20, 194, { 0b11111111, 0b11111110, 0b10110000, 0b00000000 } }, { 20, 224, { 0b11111111, 0b11111110, 0b11000000, 0b00000000 } }, { 20, 226, { 0b11111111, 0b11111110, 0b11010000, 0b00000000 } }, { 21, 153, { 0b11111111, 0b11111110, 0b11100000, 0b00000000 } }, { 21, 161, { 0b11111111, 0b11111110, 0b11101000, 0b00000000 } }, { 21, 167, { 0b11111111, 0b11111110, 0b11110000, 0b00000000 } }, { 21, 172, { 0b11111111, 0b11111110, 0b11111000, 0b00000000 } }, { 21, 176, { 0b11111111, 0b11111111, 0b00000000, 0b00000000 } }, { 21, 177, { 0b11111111, 0b11111111, 0b00001000, 0b00000000 } }, { 21, 179, { 0b11111111, 0b11111111, 0b00010000, 0b00000000 } }, { 21, 209, { 0b11111111, 0b11111111, 0b00011000, 0b00000000 } }, { 21, 216, { 0b11111111, 0b11111111, 0b00100000, 0b00000000 } }, { 21, 217, { 0b11111111, 0b11111111, 0b00101000, 0b00000000 } }, { 21, 227, { 0b11111111, 0b11111111, 0b00110000, 0b00000000 } }, { 21, 229, { 0b11111111, 0b11111111, 0b00111000, 0b00000000 } }, { 21, 230, { 0b11111111, 0b11111111, 0b01000000, 0b00000000 } }, { 22, 129, { 0b11111111, 0b11111111, 0b01001000, 0b00000000 } }, { 22, 132, { 0b11111111, 0b11111111, 0b01001100, 0b00000000 } }, { 22, 133, { 0b11111111, 0b11111111, 0b01010000, 0b00000000 } }, { 22, 134, { 0b11111111, 0b11111111, 0b01010100, 0b00000000 } }, { 22, 136, { 0b11111111, 0b11111111, 0b01011000, 0b00000000 } }, { 22, 146, { 0b11111111, 0b11111111, 0b01011100, 0b00000000 } }, { 22, 154, { 0b11111111, 0b11111111, 0b01100000, 0b00000000 } }, { 22, 156, { 0b11111111, 0b11111111, 0b01100100, 0b00000000 } }, { 22, 160, { 0b11111111, 0b11111111, 0b01101000, 0b00000000 } }, { 22, 163, { 0b11111111, 0b11111111, 0b01101100, 0b00000000 } }, { 22, 164, { 0b11111111, 0b11111111, 0b01110000, 0b00000000 } }, { 22, 169, { 0b11111111, 0b11111111, 0b01110100, 0b00000000 } }, { 22, 170, { 0b11111111, 0b11111111, 0b01111000, 0b00000000 } }, { 22, 173, { 0b11111111, 0b11111111, 0b01111100, 0b00000000 } }, { 22, 178, { 0b11111111, 0b11111111, 0b10000000, 0b00000000 } }, { 22, 181, { 0b11111111, 0b11111111, 0b10000100, 0b00000000 } }, { 22, 185, { 0b11111111, 0b11111111, 0b10001000, 0b00000000 } }, { 22, 186, { 0b11111111, 0b11111111, 0b10001100, 0b00000000 } }, { 22, 187, { 0b11111111, 0b11111111, 0b10010000, 0b00000000 } }, { 22, 189, { 0b11111111, 0b11111111, 0b10010100, 0b00000000 } }, { 22, 190, { 0b11111111, 0b11111111, 0b10011000, 0b00000000 } }, { 22, 196, { 0b11111111, 0b11111111, 0b10011100, 0b00000000 } }, { 22, 198, { 0b11111111, 0b11111111, 0b10100000, 0b00000000 } }, { 22, 228, { 0b11111111, 0b11111111, 0b10100100, 0b00000000 } }, { 22, 232, { 0b11111111, 0b11111111, 0b10101000, 0b00000000 } }, { 22, 233, { 0b11111111, 0b11111111, 0b10101100, 0b00000000 } }, { 23, 1, { 0b11111111, 0b11111111, 0b10110000, 0b00000000 } }, { 23, 135, { 0b11111111, 0b11111111, 0b10110010, 0b00000000 } }, { 23, 137, { 0b11111111, 0b11111111, 0b10110100, 0b00000000 } }, { 23, 138, { 0b11111111, 0b11111111, 0b10110110, 0b00000000 } }, { 23, 139, { 0b11111111, 0b11111111, 0b10111000, 0b00000000 } }, { 23, 140, { 0b11111111, 0b11111111, 0b10111010, 0b00000000 } }, { 23, 141, { 0b11111111, 0b11111111, 0b10111100, 0b00000000 } }, { 23, 143, { 0b11111111, 0b11111111, 0b10111110, 0b00000000 } }, { 23, 147, { 0b11111111, 0b11111111, 0b11000000, 0b00000000 } }, { 23, 149, { 0b11111111, 0b11111111, 0b11000010, 0b00000000 } }, { 23, 150, { 0b11111111, 0b11111111, 0b11000100, 0b00000000 } }, { 23, 151, { 0b11111111, 0b11111111, 0b11000110, 0b00000000 } }, { 23, 152, { 0b11111111, 0b11111111, 0b11001000, 0b00000000 } }, { 23, 155, { 0b11111111, 0b11111111, 0b11001010, 0b00000000 } }, { 23, 157, { 0b11111111, 0b11111111, 0b11001100, 0b00000000 } }, { 23, 158, { 0b11111111, 0b11111111, 0b11001110, 0b00000000 } }, { 23, 165, { 0b11111111, 0b11111111, 0b11010000, 0b00000000 } }, { 23, 166, { 0b11111111, 0b11111111, 0b11010010, 0b00000000 } }, { 23, 168, { 0b11111111, 0b11111111, 0b11010100, 0b00000000 } }, { 23, 174, { 0b11111111, 0b11111111, 0b11010110, 0b00000000 } }, { 23, 175, { 0b11111111, 0b11111111, 0b11011000, 0b00000000 } }, { 23, 180, { 0b11111111, 0b11111111, 0b11011010, 0b00000000 } }, { 23, 182, { 0b11111111, 0b11111111, 0b11011100, 0b00000000 } }, { 23, 183, { 0b11111111, 0b11111111, 0b11011110, 0b00000000 } }, { 23, 188, { 0b11111111, 0b11111111, 0b11100000, 0b00000000 } }, { 23, 191, { 0b11111111, 0b11111111, 0b11100010, 0b00000000 } }, { 23, 197, { 0b11111111, 0b11111111, 0b11100100, 0b00000000 } }, { 23, 231, { 0b11111111, 0b11111111, 0b11100110, 0b00000000 } }, { 23, 239, { 0b11111111, 0b11111111, 0b11101000, 0b00000000 } }, { 24, 9, { 0b11111111, 0b11111111, 0b11101010, 0b00000000 } }, { 24, 142, { 0b11111111, 0b11111111, 0b11101011, 0b00000000 } }, { 24, 144, { 0b11111111, 0b11111111, 0b11101100, 0b00000000 } }, { 24, 145, { 0b11111111, 0b11111111, 0b11101101, 0b00000000 } }, { 24, 148, { 0b11111111, 0b11111111, 0b11101110, 0b00000000 } }, { 24, 159, { 0b11111111, 0b11111111, 0b11101111, 0b00000000 } }, { 24, 171, { 0b11111111, 0b11111111, 0b11110000, 0b00000000 } }, { 24, 206, { 0b11111111, 0b11111111, 0b11110001, 0b00000000 } }, { 24, 215, { 0b11111111, 0b11111111, 0b11110010, 0b00000000 } }, { 24, 225, { 0b11111111, 0b11111111, 0b11110011, 0b00000000 } }, { 24, 236, { 0b11111111, 0b11111111, 0b11110100, 0b00000000 } }, { 24, 237, { 0b11111111, 0b11111111, 0b11110101, 0b00000000 } }, { 25, 199, { 0b11111111, 0b11111111, 0b11110110, 0b00000000 } }, { 25, 207, { 0b11111111, 0b11111111, 0b11110110, 0b10000000 } }, { 25, 234, { 0b11111111, 0b11111111, 0b11110111, 0b00000000 } }, { 25, 235, { 0b11111111, 0b11111111, 0b11110111, 0b10000000 } }, { 26, 192, { 0b11111111, 0b11111111, 0b11111000, 0b00000000 } }, { 26, 193, { 0b11111111, 0b11111111, 0b11111000, 0b01000000 } }, { 26, 200, { 0b11111111, 0b11111111, 0b11111000, 0b10000000 } }, { 26, 201, { 0b11111111, 0b11111111, 0b11111000, 0b11000000 } }, { 26, 202, { 0b11111111, 0b11111111, 0b11111001, 0b00000000 } }, { 26, 205, { 0b11111111, 0b11111111, 0b11111001, 0b01000000 } }, { 26, 210, { 0b11111111, 0b11111111, 0b11111001, 0b10000000 } }, { 26, 213, { 0b11111111, 0b11111111, 0b11111001, 0b11000000 } }, { 26, 218, { 0b11111111, 0b11111111, 0b11111010, 0b00000000 } }, { 26, 219, { 0b11111111, 0b11111111, 0b11111010, 0b01000000 } }, { 26, 238, { 0b11111111, 0b11111111, 0b11111010, 0b10000000 } }, { 26, 240, { 0b11111111, 0b11111111, 0b11111010, 0b11000000 } }, { 26, 242, { 0b11111111, 0b11111111, 0b11111011, 0b00000000 } }, { 26, 243, { 0b11111111, 0b11111111, 0b11111011, 0b01000000 } }, { 26, 255, { 0b11111111, 0b11111111, 0b11111011, 0b10000000 } }, { 27, 203, { 0b11111111, 0b11111111, 0b11111011, 0b11000000 } }, { 27, 204, { 0b11111111, 0b11111111, 0b11111011, 0b11100000 } }, { 27, 211, { 0b11111111, 0b11111111, 0b11111100, 0b00000000 } }, { 27, 212, { 0b11111111, 0b11111111, 0b11111100, 0b00100000 } }, { 27, 214, { 0b11111111, 0b11111111, 0b11111100, 0b01000000 } }, { 27, 221, { 0b11111111, 0b11111111, 0b11111100, 0b01100000 } }, { 27, 222, { 0b11111111, 0b11111111, 0b11111100, 0b10000000 } }, { 27, 223, { 0b11111111, 0b11111111, 0b11111100, 0b10100000 } }, { 27, 241, { 0b11111111, 0b11111111, 0b11111100, 0b11000000 } }, { 27, 244, { 0b11111111, 0b11111111, 0b11111100, 0b11100000 } }, { 27, 245, { 0b11111111, 0b11111111, 0b11111101, 0b00000000 } }, { 27, 246, { 0b11111111, 0b11111111, 0b11111101, 0b00100000 } }, { 27, 247, { 0b11111111, 0b11111111, 0b11111101, 0b01000000 } }, { 27, 248, { 0b11111111, 0b11111111, 0b11111101, 0b01100000 } }, { 27, 250, { 0b11111111, 0b11111111, 0b11111101, 0b10000000 } }, { 27, 251, { 0b11111111, 0b11111111, 0b11111101, 0b10100000 } }, { 27, 252, { 0b11111111, 0b11111111, 0b11111101, 0b11000000 } }, { 27, 253, { 0b11111111, 0b11111111, 0b11111101, 0b11100000 } }, { 27, 254, { 0b11111111, 0b11111111, 0b11111110, 0b00000000 } }, { 28, 2, { 0b11111111, 0b11111111, 0b11111110, 0b00100000 } }, { 28, 3, { 0b11111111, 0b11111111, 0b11111110, 0b00110000 } }, { 28, 4, { 0b11111111, 0b11111111, 0b11111110, 0b01000000 } }, { 28, 5, { 0b11111111, 0b11111111, 0b11111110, 0b01010000 } }, { 28, 6, { 0b11111111, 0b11111111, 0b11111110, 0b01100000 } }, { 28, 7, { 0b11111111, 0b11111111, 0b11111110, 0b01110000 } }, { 28, 8, { 0b11111111, 0b11111111, 0b11111110, 0b10000000 } }, { 28, 11, { 0b11111111, 0b11111111, 0b11111110, 0b10010000 } }, { 28, 12, { 0b11111111, 0b11111111, 0b11111110, 0b10100000 } }, { 28, 14, { 0b11111111, 0b11111111, 0b11111110, 0b10110000 } }, { 28, 15, { 0b11111111, 0b11111111, 0b11111110, 0b11000000 } }, { 28, 16, { 0b11111111, 0b11111111, 0b11111110, 0b11010000 } }, { 28, 17, { 0b11111111, 0b11111111, 0b11111110, 0b11100000 } }, { 28, 18, { 0b11111111, 0b11111111, 0b11111110, 0b11110000 } }, { 28, 19, { 0b11111111, 0b11111111, 0b11111111, 0b00000000 } }, { 28, 20, { 0b11111111, 0b11111111, 0b11111111, 0b00010000 } }, { 28, 21, { 0b11111111, 0b11111111, 0b11111111, 0b00100000 } }, { 28, 23, { 0b11111111, 0b11111111, 0b11111111, 0b00110000 } }, { 28, 24, { 0b11111111, 0b11111111, 0b11111111, 0b01000000 } }, { 28, 25, { 0b11111111, 0b11111111, 0b11111111, 0b01010000 } }, { 28, 26, { 0b11111111, 0b11111111, 0b11111111, 0b01100000 } }, { 28, 27, { 0b11111111, 0b11111111, 0b11111111, 0b01110000 } }, { 28, 28, { 0b11111111, 0b11111111, 0b11111111, 0b10000000 } }, { 28, 29, { 0b11111111, 0b11111111, 0b11111111, 0b10010000 } }, { 28, 30, { 0b11111111, 0b11111111, 0b11111111, 0b10100000 } }, { 28, 31, { 0b11111111, 0b11111111, 0b11111111, 0b10110000 } }, { 28, 127, { 0b11111111, 0b11111111, 0b11111111, 0b11000000 } }, { 28, 220, { 0b11111111, 0b11111111, 0b11111111, 0b11010000 } }, { 28, 249, { 0b11111111, 0b11111111, 0b11111111, 0b11100000 } }, { 30, 10, { 0b11111111, 0b11111111, 0b11111111, 0b11110000 } }, { 30, 13, { 0b11111111, 0b11111111, 0b11111111, 0b11110100 } }, { 30, 22, { 0b11111111, 0b11111111, 0b11111111, 0b11111000 } }, }; static const struct decode_elem eos = { 30, 0, { 0b11111111, 0b11111111, 0b11111111, 0b11111100 } }; #define UINT32_BITLEN 32 #define MSB_MASK(len) (UINT32_MAX << (UINT32_BITLEN - len)) #define LSB_MASK(len) ((1UL << len) - 1UL) static bool huffman_bits_compare(uint32_t bits, const struct decode_elem *entry) { uint32_t mask = MSB_MASK(entry->bitlen); uint32_t code = sys_get_be32(entry->code); if (code == (bits & mask)) { return true; } return false; } static const struct decode_elem *huffman_decode_bits(uint32_t bits) { for (int i = 0; i < ARRAY_SIZE(decode_table); i++) { if (huffman_bits_compare(bits, &decode_table[i])) { return &decode_table[i]; } } if (huffman_bits_compare(bits, &eos)) { return &eos; } return NULL; } static const struct decode_elem *huffman_find_entry(uint8_t symbol) { for (int i = 0; i < ARRAY_SIZE(decode_table); i++) { if (decode_table[i].symbol == symbol) { return &decode_table[i]; } } return NULL; } #define MAX_PADDING_LEN 7 int http_hpack_huffman_decode(const uint8_t *encoded_buf, size_t encoded_len, uint8_t *buf, size_t buflen) { size_t encoded_bits_len = encoded_len * 8; uint8_t bits_needed = UINT32_BITLEN; const struct decode_elem *decoded; uint8_t bits_in_byte_left = 8; size_t decoded_len = 0; uint32_t bits = 0; if (encoded_buf == NULL || buf == NULL || encoded_len == 0) { return -EINVAL; } while (encoded_bits_len > 0) { /* Refill the bits variable */ while (bits_needed > 0) { if (encoded_len > 0) { if (bits_in_byte_left <= bits_needed) { /* Consume rest of the byte */ bits <<= bits_in_byte_left; bits |= *encoded_buf & LSB_MASK(bits_in_byte_left); bits_needed -= bits_in_byte_left; bits_in_byte_left = 0; } else { /* Consume part of the byte */ bits <<= bits_needed; bits |= (*encoded_buf >> (bits_in_byte_left - bits_needed)) & LSB_MASK(bits_needed); bits_in_byte_left -= bits_needed; bits_needed = 0; } } else { /* Pad with ones */ bits <<= bits_needed; bits |= LSB_MASK(bits_needed); bits_needed = 0; } /* Move to next encoded byte */ if (bits_in_byte_left == 0) { encoded_buf++; encoded_len--; bits_in_byte_left = 8; } } /* Pass to decoder */ decoded = huffman_decode_bits(bits); if (decoded == NULL) { LOG_ERR("No symbol found"); return -EBADMSG; } if (decoded == &eos) { if (encoded_bits_len > MAX_PADDING_LEN) { LOG_ERR("eos reached prematurely"); return -EBADMSG; } break; } if (encoded_bits_len < decoded->bitlen) { LOG_ERR("Invalid symbol used for padding"); return -EBADMSG; } /* Remove consumed bits from bits variable. */ bits_needed += decoded->bitlen; encoded_bits_len -= decoded->bitlen; /* Store decoded symbol */ if (buflen == 0) { LOG_ERR("Not enough buffer to decode string"); return -ENOBUFS; } *buf = decoded->symbol; buf++; buflen--; decoded_len++; } return decoded_len; } int http_hpack_huffman_encode(const uint8_t *str, size_t str_len, uint8_t *buf, size_t buflen) { const struct decode_elem *entry; size_t buflen_bits = buflen * 8; uint8_t bit_offset = 0; int len = 0; if (str == NULL || buf == NULL || str_len == 0) { return -EINVAL; } while (str_len > 0) { uint32_t code; uint8_t bitlen; entry = huffman_find_entry(*str); if (entry == NULL) { return -EINVAL; } if (entry->bitlen > buflen_bits) { return -ENOBUFS; } bitlen = entry->bitlen; code = sys_get_be32(entry->code); while (bitlen > 0) { uint8_t to_copy = MIN(8 - bit_offset, bitlen); uint8_t byte = (uint8_t)((code & MSB_MASK(to_copy)) >> (24 + bit_offset)); /* This is way suboptimal */ if (bit_offset == 0) { *buf = byte; } else { *buf |= byte; } code <<= to_copy; bitlen -= to_copy; bit_offset = (bit_offset + to_copy) % 8; if (bit_offset == 0) { buf++; len++; } } buflen_bits -= entry->bitlen; str_len--; str++; } /* Pad with ones. */ if (bit_offset > 0) { *buf |= LSB_MASK((8 - bit_offset)); len++; } return len; }