view src/core/ngx_sha1.c @ 9067:f68fdb017141 quic

QUIC: optimized sending stream response. When a stream is created by client, it's often the case that nginx will send immediate response on that stream. An example is HTTP/3 request stream, which in most cases quickly replies with at least HTTP headers. QUIC stream init handlers are called from a posted event. Output QUIC frames are also sent to client from a posted event, called the push event. If the push event is posted before the stream init event, then output produced by stream may trigger sending an extra UDP datagram. To address this, push event is now re-posted when a new stream init event is posted. An example is handling 0-RTT packets. Client typically sends an init packet coalesced with a 0-RTT packet. Previously, nginx replied with a padded CRYPTO datagram, followed by a 1-RTT stream reply datagram. Now CRYPTO and STREAM packets are coalesced in one reply datagram, which saves bandwidth. Other examples include coalescing 1-RTT first stream response, and MAX_STREAMS/STREAM sent in response to ACK/STREAM.
author Roman Arutyunyan <arut@nginx.com>
date Mon, 03 Apr 2023 16:17:12 +0400
parents 9eefb38f0005
children
line wrap: on
line source


/*
 * Copyright (C) Maxim Dounin
 * Copyright (C) Nginx, Inc.
 *
 * An internal SHA1 implementation.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_sha1.h>


static const u_char *ngx_sha1_body(ngx_sha1_t *ctx, const u_char *data,
    size_t size);


void
ngx_sha1_init(ngx_sha1_t *ctx)
{
    ctx->a = 0x67452301;
    ctx->b = 0xefcdab89;
    ctx->c = 0x98badcfe;
    ctx->d = 0x10325476;
    ctx->e = 0xc3d2e1f0;

    ctx->bytes = 0;
}


void
ngx_sha1_update(ngx_sha1_t *ctx, const void *data, size_t size)
{
    size_t  used, free;

    used = (size_t) (ctx->bytes & 0x3f);
    ctx->bytes += size;

    if (used) {
        free = 64 - used;

        if (size < free) {
            ngx_memcpy(&ctx->buffer[used], data, size);
            return;
        }

        ngx_memcpy(&ctx->buffer[used], data, free);
        data = (u_char *) data + free;
        size -= free;
        (void) ngx_sha1_body(ctx, ctx->buffer, 64);
    }

    if (size >= 64) {
        data = ngx_sha1_body(ctx, data, size & ~(size_t) 0x3f);
        size &= 0x3f;
    }

    ngx_memcpy(ctx->buffer, data, size);
}


void
ngx_sha1_final(u_char result[20], ngx_sha1_t *ctx)
{
    size_t  used, free;

    used = (size_t) (ctx->bytes & 0x3f);

    ctx->buffer[used++] = 0x80;

    free = 64 - used;

    if (free < 8) {
        ngx_memzero(&ctx->buffer[used], free);
        (void) ngx_sha1_body(ctx, ctx->buffer, 64);
        used = 0;
        free = 64;
    }

    ngx_memzero(&ctx->buffer[used], free - 8);

    ctx->bytes <<= 3;
    ctx->buffer[56] = (u_char) (ctx->bytes >> 56);
    ctx->buffer[57] = (u_char) (ctx->bytes >> 48);
    ctx->buffer[58] = (u_char) (ctx->bytes >> 40);
    ctx->buffer[59] = (u_char) (ctx->bytes >> 32);
    ctx->buffer[60] = (u_char) (ctx->bytes >> 24);
    ctx->buffer[61] = (u_char) (ctx->bytes >> 16);
    ctx->buffer[62] = (u_char) (ctx->bytes >> 8);
    ctx->buffer[63] = (u_char) ctx->bytes;

    (void) ngx_sha1_body(ctx, ctx->buffer, 64);

    result[0] = (u_char) (ctx->a >> 24);
    result[1] = (u_char) (ctx->a >> 16);
    result[2] = (u_char) (ctx->a >> 8);
    result[3] = (u_char) ctx->a;
    result[4] = (u_char) (ctx->b >> 24);
    result[5] = (u_char) (ctx->b >> 16);
    result[6] = (u_char) (ctx->b >> 8);
    result[7] = (u_char) ctx->b;
    result[8] = (u_char) (ctx->c >> 24);
    result[9] = (u_char) (ctx->c >> 16);
    result[10] = (u_char) (ctx->c >> 8);
    result[11] = (u_char) ctx->c;
    result[12] = (u_char) (ctx->d >> 24);
    result[13] = (u_char) (ctx->d >> 16);
    result[14] = (u_char) (ctx->d >> 8);
    result[15] = (u_char) ctx->d;
    result[16] = (u_char) (ctx->e >> 24);
    result[17] = (u_char) (ctx->e >> 16);
    result[18] = (u_char) (ctx->e >> 8);
    result[19] = (u_char) ctx->e;

    ngx_memzero(ctx, sizeof(*ctx));
}


/*
 * Helper functions.
 */

#define ROTATE(bits, word)  (((word) << (bits)) | ((word) >> (32 - (bits))))

#define F1(b, c, d)  (((b) & (c)) | ((~(b)) & (d)))
#define F2(b, c, d)  ((b) ^ (c) ^ (d))
#define F3(b, c, d)  (((b) & (c)) | ((b) & (d)) | ((c) & (d)))

#define STEP(f, a, b, c, d, e, w, t)                                          \
    temp = ROTATE(5, (a)) + f((b), (c), (d)) + (e) + (w) + (t);               \
    (e) = (d);                                                                \
    (d) = (c);                                                                \
    (c) = ROTATE(30, (b));                                                    \
    (b) = (a);                                                                \
    (a) = temp;


/*
 * GET() reads 4 input bytes in big-endian byte order and returns
 * them as uint32_t.
 */

#define GET(n)                                                                \
    ((uint32_t) p[n * 4 + 3] |                                                \
    ((uint32_t) p[n * 4 + 2] << 8) |                                          \
    ((uint32_t) p[n * 4 + 1] << 16) |                                         \
    ((uint32_t) p[n * 4] << 24))


/*
 * This processes one or more 64-byte data blocks, but does not update
 * the bit counters.  There are no alignment requirements.
 */

static const u_char *
ngx_sha1_body(ngx_sha1_t *ctx, const u_char *data, size_t size)
{
    uint32_t       a, b, c, d, e, temp;
    uint32_t       saved_a, saved_b, saved_c, saved_d, saved_e;
    uint32_t       words[80];
    ngx_uint_t     i;
    const u_char  *p;

    p = data;

    a = ctx->a;
    b = ctx->b;
    c = ctx->c;
    d = ctx->d;
    e = ctx->e;

    do {
        saved_a = a;
        saved_b = b;
        saved_c = c;
        saved_d = d;
        saved_e = e;

        /* Load data block into the words array */

        for (i = 0; i < 16; i++) {
            words[i] = GET(i);
        }

        for (i = 16; i < 80; i++) {
            words[i] = ROTATE(1, words[i - 3] ^ words[i - 8] ^ words[i - 14]
                                 ^ words[i - 16]);
        }

        /* Transformations */

        STEP(F1, a, b, c, d, e, words[0],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[1],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[2],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[3],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[4],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[5],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[6],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[7],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[8],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[9],  0x5a827999);
        STEP(F1, a, b, c, d, e, words[10], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[11], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[12], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[13], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[14], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[15], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[16], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[17], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[18], 0x5a827999);
        STEP(F1, a, b, c, d, e, words[19], 0x5a827999);

        STEP(F2, a, b, c, d, e, words[20], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[21], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[22], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[23], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[24], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[25], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[26], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[27], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[28], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[29], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[30], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[31], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[32], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[33], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[34], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[35], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[36], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[37], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[38], 0x6ed9eba1);
        STEP(F2, a, b, c, d, e, words[39], 0x6ed9eba1);

        STEP(F3, a, b, c, d, e, words[40], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[41], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[42], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[43], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[44], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[45], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[46], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[47], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[48], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[49], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[50], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[51], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[52], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[53], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[54], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[55], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[56], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[57], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[58], 0x8f1bbcdc);
        STEP(F3, a, b, c, d, e, words[59], 0x8f1bbcdc);

        STEP(F2, a, b, c, d, e, words[60], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[61], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[62], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[63], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[64], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[65], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[66], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[67], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[68], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[69], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[70], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[71], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[72], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[73], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[74], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[75], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[76], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[77], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[78], 0xca62c1d6);
        STEP(F2, a, b, c, d, e, words[79], 0xca62c1d6);

        a += saved_a;
        b += saved_b;
        c += saved_c;
        d += saved_d;
        e += saved_e;

        p += 64;

    } while (size -= 64);

    ctx->a = a;
    ctx->b = b;
    ctx->c = c;
    ctx->d = d;
    ctx->e = e;

    return p;
}