Mercurial > hg > nginx
view src/http/ngx_http_huff_encode.c @ 9208:2ed3f57dca0a
QUIC: fixed unsent MTU probe acknowledgement.
Previously if an MTU probe send failed early in ngx_quic_frame_sendto()
due to allocation error or congestion control, the application level packet
number was not increased, but was still saved as MTU probe packet number.
Later when a packet with this number was acknowledged, the unsent MTU probe
was acknowledged as well. This could result in discovering a bigger MTU than
supported by the path, which could lead to EMSGSIZE (Message too long) errors
while sending further packets.
The problem existed since PMTUD was introduced in 58afcd72446f (1.25.2).
Back then only the unlikely memory allocation error could trigger it. However
in efcdaa66df2e congestion control was added to ngx_quic_frame_sendto() which
can now trigger the issue with a higher probability.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Wed, 14 Feb 2024 16:56:28 +0400 |
parents | 336084ff943b |
children |
line wrap: on
line source
/* * Copyright (C) Nginx, Inc. * Copyright (C) Valentin V. Bartenev * Copyright (C) 2015 Vlad Krasnov */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { uint32_t code; uint32_t len; } ngx_http_huff_encode_code_t; static ngx_http_huff_encode_code_t ngx_http_huff_encode_table[256] = { {0x00001ff8, 13}, {0x007fffd8, 23}, {0x0fffffe2, 28}, {0x0fffffe3, 28}, {0x0fffffe4, 28}, {0x0fffffe5, 28}, {0x0fffffe6, 28}, {0x0fffffe7, 28}, {0x0fffffe8, 28}, {0x00ffffea, 24}, {0x3ffffffc, 30}, {0x0fffffe9, 28}, {0x0fffffea, 28}, {0x3ffffffd, 30}, {0x0fffffeb, 28}, {0x0fffffec, 28}, {0x0fffffed, 28}, {0x0fffffee, 28}, {0x0fffffef, 28}, {0x0ffffff0, 28}, {0x0ffffff1, 28}, {0x0ffffff2, 28}, {0x3ffffffe, 30}, {0x0ffffff3, 28}, {0x0ffffff4, 28}, {0x0ffffff5, 28}, {0x0ffffff6, 28}, {0x0ffffff7, 28}, {0x0ffffff8, 28}, {0x0ffffff9, 28}, {0x0ffffffa, 28}, {0x0ffffffb, 28}, {0x00000014, 6}, {0x000003f8, 10}, {0x000003f9, 10}, {0x00000ffa, 12}, {0x00001ff9, 13}, {0x00000015, 6}, {0x000000f8, 8}, {0x000007fa, 11}, {0x000003fa, 10}, {0x000003fb, 10}, {0x000000f9, 8}, {0x000007fb, 11}, {0x000000fa, 8}, {0x00000016, 6}, {0x00000017, 6}, {0x00000018, 6}, {0x00000000, 5}, {0x00000001, 5}, {0x00000002, 5}, {0x00000019, 6}, {0x0000001a, 6}, {0x0000001b, 6}, {0x0000001c, 6}, {0x0000001d, 6}, {0x0000001e, 6}, {0x0000001f, 6}, {0x0000005c, 7}, {0x000000fb, 8}, {0x00007ffc, 15}, {0x00000020, 6}, {0x00000ffb, 12}, {0x000003fc, 10}, {0x00001ffa, 13}, {0x00000021, 6}, {0x0000005d, 7}, {0x0000005e, 7}, {0x0000005f, 7}, {0x00000060, 7}, {0x00000061, 7}, {0x00000062, 7}, {0x00000063, 7}, {0x00000064, 7}, {0x00000065, 7}, {0x00000066, 7}, {0x00000067, 7}, {0x00000068, 7}, {0x00000069, 7}, {0x0000006a, 7}, {0x0000006b, 7}, {0x0000006c, 7}, {0x0000006d, 7}, {0x0000006e, 7}, {0x0000006f, 7}, {0x00000070, 7}, {0x00000071, 7}, {0x00000072, 7}, {0x000000fc, 8}, {0x00000073, 7}, {0x000000fd, 8}, {0x00001ffb, 13}, {0x0007fff0, 19}, {0x00001ffc, 13}, {0x00003ffc, 14}, {0x00000022, 6}, {0x00007ffd, 15}, {0x00000003, 5}, {0x00000023, 6}, {0x00000004, 5}, {0x00000024, 6}, {0x00000005, 5}, {0x00000025, 6}, {0x00000026, 6}, {0x00000027, 6}, {0x00000006, 5}, {0x00000074, 7}, {0x00000075, 7}, {0x00000028, 6}, {0x00000029, 6}, {0x0000002a, 6}, {0x00000007, 5}, {0x0000002b, 6}, {0x00000076, 7}, {0x0000002c, 6}, {0x00000008, 5}, {0x00000009, 5}, {0x0000002d, 6}, {0x00000077, 7}, {0x00000078, 7}, {0x00000079, 7}, {0x0000007a, 7}, {0x0000007b, 7}, {0x00007ffe, 15}, {0x000007fc, 11}, {0x00003ffd, 14}, {0x00001ffd, 13}, {0x0ffffffc, 28}, {0x000fffe6, 20}, {0x003fffd2, 22}, {0x000fffe7, 20}, {0x000fffe8, 20}, {0x003fffd3, 22}, {0x003fffd4, 22}, {0x003fffd5, 22}, {0x007fffd9, 23}, {0x003fffd6, 22}, {0x007fffda, 23}, {0x007fffdb, 23}, {0x007fffdc, 23}, {0x007fffdd, 23}, {0x007fffde, 23}, {0x00ffffeb, 24}, {0x007fffdf, 23}, {0x00ffffec, 24}, {0x00ffffed, 24}, {0x003fffd7, 22}, {0x007fffe0, 23}, {0x00ffffee, 24}, {0x007fffe1, 23}, {0x007fffe2, 23}, {0x007fffe3, 23}, {0x007fffe4, 23}, {0x001fffdc, 21}, {0x003fffd8, 22}, {0x007fffe5, 23}, {0x003fffd9, 22}, {0x007fffe6, 23}, {0x007fffe7, 23}, {0x00ffffef, 24}, {0x003fffda, 22}, {0x001fffdd, 21}, {0x000fffe9, 20}, {0x003fffdb, 22}, {0x003fffdc, 22}, {0x007fffe8, 23}, {0x007fffe9, 23}, {0x001fffde, 21}, {0x007fffea, 23}, {0x003fffdd, 22}, {0x003fffde, 22}, {0x00fffff0, 24}, {0x001fffdf, 21}, {0x003fffdf, 22}, {0x007fffeb, 23}, {0x007fffec, 23}, {0x001fffe0, 21}, {0x001fffe1, 21}, {0x003fffe0, 22}, {0x001fffe2, 21}, {0x007fffed, 23}, {0x003fffe1, 22}, {0x007fffee, 23}, {0x007fffef, 23}, {0x000fffea, 20}, {0x003fffe2, 22}, {0x003fffe3, 22}, {0x003fffe4, 22}, {0x007ffff0, 23}, {0x003fffe5, 22}, {0x003fffe6, 22}, {0x007ffff1, 23}, {0x03ffffe0, 26}, {0x03ffffe1, 26}, {0x000fffeb, 20}, {0x0007fff1, 19}, {0x003fffe7, 22}, {0x007ffff2, 23}, {0x003fffe8, 22}, {0x01ffffec, 25}, {0x03ffffe2, 26}, {0x03ffffe3, 26}, {0x03ffffe4, 26}, {0x07ffffde, 27}, {0x07ffffdf, 27}, {0x03ffffe5, 26}, {0x00fffff1, 24}, {0x01ffffed, 25}, {0x0007fff2, 19}, {0x001fffe3, 21}, {0x03ffffe6, 26}, {0x07ffffe0, 27}, {0x07ffffe1, 27}, {0x03ffffe7, 26}, {0x07ffffe2, 27}, {0x00fffff2, 24}, {0x001fffe4, 21}, {0x001fffe5, 21}, {0x03ffffe8, 26}, {0x03ffffe9, 26}, {0x0ffffffd, 28}, {0x07ffffe3, 27}, {0x07ffffe4, 27}, {0x07ffffe5, 27}, {0x000fffec, 20}, {0x00fffff3, 24}, {0x000fffed, 20}, {0x001fffe6, 21}, {0x003fffe9, 22}, {0x001fffe7, 21}, {0x001fffe8, 21}, {0x007ffff3, 23}, {0x003fffea, 22}, {0x003fffeb, 22}, {0x01ffffee, 25}, {0x01ffffef, 25}, {0x00fffff4, 24}, {0x00fffff5, 24}, {0x03ffffea, 26}, {0x007ffff4, 23}, {0x03ffffeb, 26}, {0x07ffffe6, 27}, {0x03ffffec, 26}, {0x03ffffed, 26}, {0x07ffffe7, 27}, {0x07ffffe8, 27}, {0x07ffffe9, 27}, {0x07ffffea, 27}, {0x07ffffeb, 27}, {0x0ffffffe, 28}, {0x07ffffec, 27}, {0x07ffffed, 27}, {0x07ffffee, 27}, {0x07ffffef, 27}, {0x07fffff0, 27}, {0x03ffffee, 26} }; /* same as above, but embeds lowercase transformation */ static ngx_http_huff_encode_code_t ngx_http_huff_encode_table_lc[256] = { {0x00001ff8, 13}, {0x007fffd8, 23}, {0x0fffffe2, 28}, {0x0fffffe3, 28}, {0x0fffffe4, 28}, {0x0fffffe5, 28}, {0x0fffffe6, 28}, {0x0fffffe7, 28}, {0x0fffffe8, 28}, {0x00ffffea, 24}, {0x3ffffffc, 30}, {0x0fffffe9, 28}, {0x0fffffea, 28}, {0x3ffffffd, 30}, {0x0fffffeb, 28}, {0x0fffffec, 28}, {0x0fffffed, 28}, {0x0fffffee, 28}, {0x0fffffef, 28}, {0x0ffffff0, 28}, {0x0ffffff1, 28}, {0x0ffffff2, 28}, {0x3ffffffe, 30}, {0x0ffffff3, 28}, {0x0ffffff4, 28}, {0x0ffffff5, 28}, {0x0ffffff6, 28}, {0x0ffffff7, 28}, {0x0ffffff8, 28}, {0x0ffffff9, 28}, {0x0ffffffa, 28}, {0x0ffffffb, 28}, {0x00000014, 6}, {0x000003f8, 10}, {0x000003f9, 10}, {0x00000ffa, 12}, {0x00001ff9, 13}, {0x00000015, 6}, {0x000000f8, 8}, {0x000007fa, 11}, {0x000003fa, 10}, {0x000003fb, 10}, {0x000000f9, 8}, {0x000007fb, 11}, {0x000000fa, 8}, {0x00000016, 6}, {0x00000017, 6}, {0x00000018, 6}, {0x00000000, 5}, {0x00000001, 5}, {0x00000002, 5}, {0x00000019, 6}, {0x0000001a, 6}, {0x0000001b, 6}, {0x0000001c, 6}, {0x0000001d, 6}, {0x0000001e, 6}, {0x0000001f, 6}, {0x0000005c, 7}, {0x000000fb, 8}, {0x00007ffc, 15}, {0x00000020, 6}, {0x00000ffb, 12}, {0x000003fc, 10}, {0x00001ffa, 13}, {0x00000003, 5}, {0x00000023, 6}, {0x00000004, 5}, {0x00000024, 6}, {0x00000005, 5}, {0x00000025, 6}, {0x00000026, 6}, {0x00000027, 6}, {0x00000006, 5}, {0x00000074, 7}, {0x00000075, 7}, {0x00000028, 6}, {0x00000029, 6}, {0x0000002a, 6}, {0x00000007, 5}, {0x0000002b, 6}, {0x00000076, 7}, {0x0000002c, 6}, {0x00000008, 5}, {0x00000009, 5}, {0x0000002d, 6}, {0x00000077, 7}, {0x00000078, 7}, {0x00000079, 7}, {0x0000007a, 7}, {0x0000007b, 7}, {0x00001ffb, 13}, {0x0007fff0, 19}, {0x00001ffc, 13}, {0x00003ffc, 14}, {0x00000022, 6}, {0x00007ffd, 15}, {0x00000003, 5}, {0x00000023, 6}, {0x00000004, 5}, {0x00000024, 6}, {0x00000005, 5}, {0x00000025, 6}, {0x00000026, 6}, {0x00000027, 6}, {0x00000006, 5}, {0x00000074, 7}, {0x00000075, 7}, {0x00000028, 6}, {0x00000029, 6}, {0x0000002a, 6}, {0x00000007, 5}, {0x0000002b, 6}, {0x00000076, 7}, {0x0000002c, 6}, {0x00000008, 5}, {0x00000009, 5}, {0x0000002d, 6}, {0x00000077, 7}, {0x00000078, 7}, {0x00000079, 7}, {0x0000007a, 7}, {0x0000007b, 7}, {0x00007ffe, 15}, {0x000007fc, 11}, {0x00003ffd, 14}, {0x00001ffd, 13}, {0x0ffffffc, 28}, {0x000fffe6, 20}, {0x003fffd2, 22}, {0x000fffe7, 20}, {0x000fffe8, 20}, {0x003fffd3, 22}, {0x003fffd4, 22}, {0x003fffd5, 22}, {0x007fffd9, 23}, {0x003fffd6, 22}, {0x007fffda, 23}, {0x007fffdb, 23}, {0x007fffdc, 23}, {0x007fffdd, 23}, {0x007fffde, 23}, {0x00ffffeb, 24}, {0x007fffdf, 23}, {0x00ffffec, 24}, {0x00ffffed, 24}, {0x003fffd7, 22}, {0x007fffe0, 23}, {0x00ffffee, 24}, {0x007fffe1, 23}, {0x007fffe2, 23}, {0x007fffe3, 23}, {0x007fffe4, 23}, {0x001fffdc, 21}, {0x003fffd8, 22}, {0x007fffe5, 23}, {0x003fffd9, 22}, {0x007fffe6, 23}, {0x007fffe7, 23}, {0x00ffffef, 24}, {0x003fffda, 22}, {0x001fffdd, 21}, {0x000fffe9, 20}, {0x003fffdb, 22}, {0x003fffdc, 22}, {0x007fffe8, 23}, {0x007fffe9, 23}, {0x001fffde, 21}, {0x007fffea, 23}, {0x003fffdd, 22}, {0x003fffde, 22}, {0x00fffff0, 24}, {0x001fffdf, 21}, {0x003fffdf, 22}, {0x007fffeb, 23}, {0x007fffec, 23}, {0x001fffe0, 21}, {0x001fffe1, 21}, {0x003fffe0, 22}, {0x001fffe2, 21}, {0x007fffed, 23}, {0x003fffe1, 22}, {0x007fffee, 23}, {0x007fffef, 23}, {0x000fffea, 20}, {0x003fffe2, 22}, {0x003fffe3, 22}, {0x003fffe4, 22}, {0x007ffff0, 23}, {0x003fffe5, 22}, {0x003fffe6, 22}, {0x007ffff1, 23}, {0x03ffffe0, 26}, {0x03ffffe1, 26}, {0x000fffeb, 20}, {0x0007fff1, 19}, {0x003fffe7, 22}, {0x007ffff2, 23}, {0x003fffe8, 22}, {0x01ffffec, 25}, {0x03ffffe2, 26}, {0x03ffffe3, 26}, {0x03ffffe4, 26}, {0x07ffffde, 27}, {0x07ffffdf, 27}, {0x03ffffe5, 26}, {0x00fffff1, 24}, {0x01ffffed, 25}, {0x0007fff2, 19}, {0x001fffe3, 21}, {0x03ffffe6, 26}, {0x07ffffe0, 27}, {0x07ffffe1, 27}, {0x03ffffe7, 26}, {0x07ffffe2, 27}, {0x00fffff2, 24}, {0x001fffe4, 21}, {0x001fffe5, 21}, {0x03ffffe8, 26}, {0x03ffffe9, 26}, {0x0ffffffd, 28}, {0x07ffffe3, 27}, {0x07ffffe4, 27}, {0x07ffffe5, 27}, {0x000fffec, 20}, {0x00fffff3, 24}, {0x000fffed, 20}, {0x001fffe6, 21}, {0x003fffe9, 22}, {0x001fffe7, 21}, {0x001fffe8, 21}, {0x007ffff3, 23}, {0x003fffea, 22}, {0x003fffeb, 22}, {0x01ffffee, 25}, {0x01ffffef, 25}, {0x00fffff4, 24}, {0x00fffff5, 24}, {0x03ffffea, 26}, {0x007ffff4, 23}, {0x03ffffeb, 26}, {0x07ffffe6, 27}, {0x03ffffec, 26}, {0x03ffffed, 26}, {0x07ffffe7, 27}, {0x07ffffe8, 27}, {0x07ffffe9, 27}, {0x07ffffea, 27}, {0x07ffffeb, 27}, {0x0ffffffe, 28}, {0x07ffffec, 27}, {0x07ffffed, 27}, {0x07ffffee, 27}, {0x07ffffef, 27}, {0x07fffff0, 27}, {0x03ffffee, 26} }; #if (NGX_PTR_SIZE == 8) #if (NGX_HAVE_LITTLE_ENDIAN) #if (NGX_HAVE_GCC_BSWAP64) #define ngx_http_huff_encode_buf(dst, buf) \ (*(uint64_t *) (dst) = __builtin_bswap64(buf)) #else #define ngx_http_huff_encode_buf(dst, buf) \ ((dst)[0] = (u_char) ((buf) >> 56), \ (dst)[1] = (u_char) ((buf) >> 48), \ (dst)[2] = (u_char) ((buf) >> 40), \ (dst)[3] = (u_char) ((buf) >> 32), \ (dst)[4] = (u_char) ((buf) >> 24), \ (dst)[5] = (u_char) ((buf) >> 16), \ (dst)[6] = (u_char) ((buf) >> 8), \ (dst)[7] = (u_char) (buf)) #endif #else /* !NGX_HAVE_LITTLE_ENDIAN */ #define ngx_http_huff_encode_buf(dst, buf) \ (*(uint64_t *) (dst) = (buf)) #endif #else /* NGX_PTR_SIZE == 4 */ #define ngx_http_huff_encode_buf(dst, buf) \ (*(uint32_t *) (dst) = htonl(buf)) #endif size_t ngx_http_huff_encode(u_char *src, size_t len, u_char *dst, ngx_uint_t lower) { u_char *end; size_t hlen; ngx_uint_t buf, pending, code; ngx_http_huff_encode_code_t *table, *next; table = lower ? ngx_http_huff_encode_table_lc : ngx_http_huff_encode_table; hlen = 0; buf = 0; pending = 0; end = src + len; while (src != end) { next = &table[*src++]; code = next->code; pending += next->len; /* accumulate bits */ if (pending < sizeof(buf) * 8) { buf |= code << (sizeof(buf) * 8 - pending); continue; } if (hlen + sizeof(buf) >= len) { return 0; } pending -= sizeof(buf) * 8; buf |= code >> pending; ngx_http_huff_encode_buf(&dst[hlen], buf); hlen += sizeof(buf); buf = pending ? code << (sizeof(buf) * 8 - pending) : 0; } if (pending == 0) { return hlen; } buf |= (ngx_uint_t) -1 >> pending; pending = ngx_align(pending, 8); if (hlen + pending / 8 >= len) { return 0; } buf >>= sizeof(buf) * 8 - pending; do { pending -= 8; dst[hlen++] = (u_char) (buf >> pending); } while (pending); return hlen; }