view src/core/ngx_sha1.c @ 8006:32b0ba4855a6

HTTP/2: made it possible to flush response headers (ticket #1743). Response headers can be buffered in the SSL buffer. But stream's fake connection buffered flag did not reflect this, so any attempts to flush the buffer without sending additional data were stopped by the write filter. It does not seem to be possible to reflect this in fc->buffered though, as we never known if main connection's c->buffered corresponds to the particular stream or not. As such, fc->buffered might prevent request finalization due to sending data on some other stream. Fix is to implement handling of flush buffers when the c->need_flush_buf flag is set, similarly to the existing last buffer handling. The same flag is now used for UDP sockets in the stream module instead of explicit checking of c->type.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 03 Feb 2022 01:44:38 +0300
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;
}