sha1.c

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/*-------------------------------------------------------------------------
 *
 *  sha1.c
 *    Implements the SHA1 Secure Hash Algorithm
 *
 * Fallback implementation of SHA1, as specified in RFC 3174.
 *
 * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
 *    src/common/sha1.c
 *
 *-------------------------------------------------------------------------
 */
 
/*     $KAME: sha1.c,v 1.3 2000/02/22 14:01:18 itojun Exp $    */
 
/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
/*
 * FIPS pub 180-1: Secure Hash Algorithm (SHA-1)
 * based on: http://www.itl.nist.gov/fipspubs/fip180-1.htm
 * implemented by Jun-ichiro itojun Itoh <itojun@itojun.org>
 */
 
#ifndef FRONTEND
#include "postgres.h"
#else
#include "postgres_fe.h"
#endif
 
#include <sys/param.h>
 
#include "sha1_int.h"
 
/* constant table */
static const uint32 _K[] = {0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6};
 
#define K(t)    _K[(t) / 20]
 
#define F0(b, c, d) (((b) & (c)) | ((~(b)) & (d)))
#define F1(b, c, d) (((b) ^ (c)) ^ (d))
#define F2(b, c, d) (((b) & (c)) | ((b) & (d)) | ((c) & (d)))
#define F3(b, c, d) (((b) ^ (c)) ^ (d))
 
#define S(n, x)     (((x) << (n)) | ((x) >> (32 - (n))))
 
#define H(n)    (ctx->h.b32[(n)])
#define COUNT   (ctx->count)
#define BCOUNT  (ctx->c.b64[0] / 8)
#define W(n)    (ctx->m.b32[(n)])
 
#define PUTPAD(x) \
do { \
    ctx->m.b8[(COUNT % 64)] = (x);      \
    COUNT++;                \
    COUNT %= 64;                \
    if (COUNT % 64 == 0)            \
        sha1_step(ctx);     \
} while (0)
 
static void
sha1_step(pg_sha1_ctx *ctx)
{
    uint32      a,
                b,
                c,
                d,
                e;
    size_t      t,
                s;
    uint32      tmp;
 
#ifndef WORDS_BIGENDIAN
    pg_sha1_ctx tctx;
 
    memmove(&tctx.m.b8[0], &ctx->m.b8[0], 64);
    ctx->m.b8[0] = tctx.m.b8[3];
    ctx->m.b8[1] = tctx.m.b8[2];
    ctx->m.b8[2] = tctx.m.b8[1];
    ctx->m.b8[3] = tctx.m.b8[0];
    ctx->m.b8[4] = tctx.m.b8[7];
    ctx->m.b8[5] = tctx.m.b8[6];
    ctx->m.b8[6] = tctx.m.b8[5];
    ctx->m.b8[7] = tctx.m.b8[4];
    ctx->m.b8[8] = tctx.m.b8[11];
    ctx->m.b8[9] = tctx.m.b8[10];
    ctx->m.b8[10] = tctx.m.b8[9];
    ctx->m.b8[11] = tctx.m.b8[8];
    ctx->m.b8[12] = tctx.m.b8[15];
    ctx->m.b8[13] = tctx.m.b8[14];
    ctx->m.b8[14] = tctx.m.b8[13];
    ctx->m.b8[15] = tctx.m.b8[12];
    ctx->m.b8[16] = tctx.m.b8[19];
    ctx->m.b8[17] = tctx.m.b8[18];
    ctx->m.b8[18] = tctx.m.b8[17];
    ctx->m.b8[19] = tctx.m.b8[16];
    ctx->m.b8[20] = tctx.m.b8[23];
    ctx->m.b8[21] = tctx.m.b8[22];
    ctx->m.b8[22] = tctx.m.b8[21];
    ctx->m.b8[23] = tctx.m.b8[20];
    ctx->m.b8[24] = tctx.m.b8[27];
    ctx->m.b8[25] = tctx.m.b8[26];
    ctx->m.b8[26] = tctx.m.b8[25];
    ctx->m.b8[27] = tctx.m.b8[24];
    ctx->m.b8[28] = tctx.m.b8[31];
    ctx->m.b8[29] = tctx.m.b8[30];
    ctx->m.b8[30] = tctx.m.b8[29];
    ctx->m.b8[31] = tctx.m.b8[28];
    ctx->m.b8[32] = tctx.m.b8[35];
    ctx->m.b8[33] = tctx.m.b8[34];
    ctx->m.b8[34] = tctx.m.b8[33];
    ctx->m.b8[35] = tctx.m.b8[32];
    ctx->m.b8[36] = tctx.m.b8[39];
    ctx->m.b8[37] = tctx.m.b8[38];
    ctx->m.b8[38] = tctx.m.b8[37];
    ctx->m.b8[39] = tctx.m.b8[36];
    ctx->m.b8[40] = tctx.m.b8[43];
    ctx->m.b8[41] = tctx.m.b8[42];
    ctx->m.b8[42] = tctx.m.b8[41];
    ctx->m.b8[43] = tctx.m.b8[40];
    ctx->m.b8[44] = tctx.m.b8[47];
    ctx->m.b8[45] = tctx.m.b8[46];
    ctx->m.b8[46] = tctx.m.b8[45];
    ctx->m.b8[47] = tctx.m.b8[44];
    ctx->m.b8[48] = tctx.m.b8[51];
    ctx->m.b8[49] = tctx.m.b8[50];
    ctx->m.b8[50] = tctx.m.b8[49];
    ctx->m.b8[51] = tctx.m.b8[48];
    ctx->m.b8[52] = tctx.m.b8[55];
    ctx->m.b8[53] = tctx.m.b8[54];
    ctx->m.b8[54] = tctx.m.b8[53];
    ctx->m.b8[55] = tctx.m.b8[52];
    ctx->m.b8[56] = tctx.m.b8[59];
    ctx->m.b8[57] = tctx.m.b8[58];
    ctx->m.b8[58] = tctx.m.b8[57];
    ctx->m.b8[59] = tctx.m.b8[56];
    ctx->m.b8[60] = tctx.m.b8[63];
    ctx->m.b8[61] = tctx.m.b8[62];
    ctx->m.b8[62] = tctx.m.b8[61];
    ctx->m.b8[63] = tctx.m.b8[60];
#endif
 
    a = H(0);
    b = H(1);
    c = H(2);
    d = H(3);
    e = H(4);
 
    for (t = 0; t < 20; t++)
    {
        s = t & 0x0f;
        if (t >= 16)
            W(s) = S(1, W((s + 13) & 0x0f) ^ W((s + 8) & 0x0f) ^ W((s + 2) & 0x0f) ^ W(s));
        tmp = S(5, a) + F0(b, c, d) + e + W(s) + K(t);
        e = d;
        d = c;
        c = S(30, b);
        b = a;
        a = tmp;
    }
    for (t = 20; t < 40; t++)
    {
        s = t & 0x0f;
        W(s) = S(1, W((s + 13) & 0x0f) ^ W((s + 8) & 0x0f) ^ W((s + 2) & 0x0f) ^ W(s));
        tmp = S(5, a) + F1(b, c, d) + e + W(s) + K(t);
        e = d;
        d = c;
        c = S(30, b);
        b = a;
        a = tmp;
    }
    for (t = 40; t < 60; t++)
    {
        s = t & 0x0f;
        W(s) = S(1, W((s + 13) & 0x0f) ^ W((s + 8) & 0x0f) ^ W((s + 2) & 0x0f) ^ W(s));
        tmp = S(5, a) + F2(b, c, d) + e + W(s) + K(t);
        e = d;
        d = c;
        c = S(30, b);
        b = a;
        a = tmp;
    }
    for (t = 60; t < 80; t++)
    {
        s = t & 0x0f;
        W(s) = S(1, W((s + 13) & 0x0f) ^ W((s + 8) & 0x0f) ^ W((s + 2) & 0x0f) ^ W(s));
        tmp = S(5, a) + F3(b, c, d) + e + W(s) + K(t);
        e = d;
        d = c;
        c = S(30, b);
        b = a;
        a = tmp;
    }
 
    H(0) = H(0) + a;
    H(1) = H(1) + b;
    H(2) = H(2) + c;
    H(3) = H(3) + d;
    H(4) = H(4) + e;
 
    memset(&ctx->m.b8[0], 0, 64);
}
 
static void
sha1_pad(pg_sha1_ctx *ctx)
{
    size_t      padlen;         /* pad length in bytes */
    size_t      padstart;
 
    PUTPAD(0x80);
 
    padstart = COUNT % 64;
    padlen = 64 - padstart;
    if (padlen < 8)
    {
        memset(&ctx->m.b8[padstart], 0, padlen);
        COUNT += padlen;
        COUNT %= 64;
        sha1_step(ctx);
        padstart = COUNT % 64;  /* should be 0 */
        padlen = 64 - padstart; /* should be 64 */
    }
    memset(&ctx->m.b8[padstart], 0, padlen - 8);
    COUNT += (padlen - 8);
    COUNT %= 64;
#ifdef WORDS_BIGENDIAN
    PUTPAD(ctx->c.b8[0]);
    PUTPAD(ctx->c.b8[1]);
    PUTPAD(ctx->c.b8[2]);
    PUTPAD(ctx->c.b8[3]);
    PUTPAD(ctx->c.b8[4]);
    PUTPAD(ctx->c.b8[5]);
    PUTPAD(ctx->c.b8[6]);
    PUTPAD(ctx->c.b8[7]);
#else
    PUTPAD(ctx->c.b8[7]);
    PUTPAD(ctx->c.b8[6]);
    PUTPAD(ctx->c.b8[5]);
    PUTPAD(ctx->c.b8[4]);
    PUTPAD(ctx->c.b8[3]);
    PUTPAD(ctx->c.b8[2]);
    PUTPAD(ctx->c.b8[1]);
    PUTPAD(ctx->c.b8[0]);
#endif
}
 
static void
sha1_result(uint8 *digest0, pg_sha1_ctx *ctx)
{
    uint8      *digest;
 
    digest = digest0;
 
#ifdef WORDS_BIGENDIAN
    memmove(digest, &ctx->h.b8[0], 20);
#else
    digest[0] = ctx->h.b8[3];
    digest[1] = ctx->h.b8[2];
    digest[2] = ctx->h.b8[1];
    digest[3] = ctx->h.b8[0];
    digest[4] = ctx->h.b8[7];
    digest[5] = ctx->h.b8[6];
    digest[6] = ctx->h.b8[5];
    digest[7] = ctx->h.b8[4];
    digest[8] = ctx->h.b8[11];
    digest[9] = ctx->h.b8[10];
    digest[10] = ctx->h.b8[9];
    digest[11] = ctx->h.b8[8];
    digest[12] = ctx->h.b8[15];
    digest[13] = ctx->h.b8[14];
    digest[14] = ctx->h.b8[13];
    digest[15] = ctx->h.b8[12];
    digest[16] = ctx->h.b8[19];
    digest[17] = ctx->h.b8[18];
    digest[18] = ctx->h.b8[17];
    digest[19] = ctx->h.b8[16];
#endif
}
 
/* External routines for this SHA1 implementation */
 
/*
 * pg_sha1_init
 *
 * Initialize a SHA1 context.
 */
void
pg_sha1_init(pg_sha1_ctx *ctx)
{
    memset(ctx, 0, sizeof(pg_sha1_ctx));
    H(0) = 0x67452301;
    H(1) = 0xefcdab89;
    H(2) = 0x98badcfe;
    H(3) = 0x10325476;
    H(4) = 0xc3d2e1f0;
}
 
/*
 * pg_sha1_update
 *
 * Update a SHA1 context.
 */
void
pg_sha1_update(pg_sha1_ctx *ctx, const uint8 *data, size_t len)
{
    const uint8 *input;
    size_t      gaplen;
    size_t      gapstart;
    size_t      off;
    size_t      copysiz;
 
    input = data;
    off = 0;
 
    while (off < len)
    {
        gapstart = COUNT % 64;
        gaplen = 64 - gapstart;
 
        copysiz = (gaplen < len - off) ? gaplen : len - off;
        memmove(&ctx->m.b8[gapstart], &input[off], copysiz);
        COUNT += copysiz;
        COUNT %= 64;
        ctx->c.b64[0] += copysiz * 8;
        if (COUNT % 64 == 0)
            sha1_step(ctx);
        off += copysiz;
    }
}
 
/*
 * pg_sha1_final
 *
 * Finalize a SHA1 context.
 */
void
pg_sha1_final(pg_sha1_ctx *ctx, uint8 *dest)
{
    sha1_pad(ctx);
    sha1_result(dest, ctx);
}