From bbe35a6e1b54ef5cd7c1c471886c30ba85c0804e Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 19:47:50 +0200 Subject: Adding upstream version 1.21. Signed-off-by: Daniel Baumann --- lib/md4.c | 382 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 382 insertions(+) create mode 100644 lib/md4.c (limited to 'lib/md4.c') diff --git a/lib/md4.c b/lib/md4.c new file mode 100644 index 0000000..6ebad1b --- /dev/null +++ b/lib/md4.c @@ -0,0 +1,382 @@ +/* Functions to compute MD4 message digest of files or memory blocks. + according to the definition of MD4 in RFC 1320 from April 1992. + Copyright (C) 1995-1997, 1999-2003, 2005-2006, 2008-2020 Free Software + Foundation, Inc. + + This program is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by the + Free Software Foundation; either version 3, or (at your option) any + later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, see . */ + +/* Adapted by Simon Josefsson from gnulib md5.? and Libgcrypt + cipher/md4.c . */ + +#include + +#include "md4.h" + +#include +#include +#include +#include +#include + +#if USE_UNLOCKED_IO +# include "unlocked-io.h" +#endif + +#include +#ifdef WORDS_BIGENDIAN +# define SWAP(n) bswap_32 (n) +#else +# define SWAP(n) (n) +#endif + +#define BLOCKSIZE 32768 +#if BLOCKSIZE % 64 != 0 +# error "invalid BLOCKSIZE" +#endif + +/* This array contains the bytes used to pad the buffer to the next + 64-byte boundary. (RFC 1320, 3.1: Step 1) */ +static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ... */ }; + + +/* Initialize structure containing state of computation. + (RFC 1320, 3.3: Step 3) */ +void +md4_init_ctx (struct md4_ctx *ctx) +{ + ctx->A = 0x67452301; + ctx->B = 0xefcdab89; + ctx->C = 0x98badcfe; + ctx->D = 0x10325476; + + ctx->total[0] = ctx->total[1] = 0; + ctx->buflen = 0; +} + +/* Copy the 4 byte value from v into the memory location pointed to by *cp, + If your architecture allows unaligned access this is equivalent to + * (uint32_t *) cp = v */ +static void +set_uint32 (char *cp, uint32_t v) +{ + memcpy (cp, &v, sizeof v); +} + +/* Put result from CTX in first 16 bytes following RESBUF. The result + must be in little endian byte order. */ +void * +md4_read_ctx (const struct md4_ctx *ctx, void *resbuf) +{ + char *r = resbuf; + set_uint32 (r + 0 * sizeof ctx->A, SWAP (ctx->A)); + set_uint32 (r + 1 * sizeof ctx->B, SWAP (ctx->B)); + set_uint32 (r + 2 * sizeof ctx->C, SWAP (ctx->C)); + set_uint32 (r + 3 * sizeof ctx->D, SWAP (ctx->D)); + + return resbuf; +} + +/* Process the remaining bytes in the internal buffer and the usual + prolog according to the standard and write the result to RESBUF. */ +void * +md4_finish_ctx (struct md4_ctx *ctx, void *resbuf) +{ + /* Take yet unprocessed bytes into account. */ + uint32_t bytes = ctx->buflen; + size_t pad; + + /* Now count remaining bytes. */ + ctx->total[0] += bytes; + if (ctx->total[0] < bytes) + ++ctx->total[1]; + + pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes; + memcpy (&((char*)ctx->buffer)[bytes], fillbuf, pad); + + /* Put the 64-bit file length in *bits* at the end of the buffer. */ + ctx->buffer[(bytes + pad) / 4] = SWAP (ctx->total[0] << 3); + ctx->buffer[(bytes + pad) / 4 + 1] = SWAP ((ctx->total[1] << 3) | + (ctx->total[0] >> 29)); + + /* Process last bytes. */ + md4_process_block (ctx->buffer, bytes + pad + 8, ctx); + + return md4_read_ctx (ctx, resbuf); +} + +/* Compute MD4 message digest for bytes read from STREAM. The + resulting message digest number will be written into the 16 bytes + beginning at RESBLOCK. */ +int +md4_stream (FILE * stream, void *resblock) +{ + struct md4_ctx ctx; + size_t sum; + + char *buffer = malloc (BLOCKSIZE + 72); + if (!buffer) + return 1; + + /* Initialize the computation context. */ + md4_init_ctx (&ctx); + + /* Iterate over full file contents. */ + while (1) + { + /* We read the file in blocks of BLOCKSIZE bytes. One call of the + computation function processes the whole buffer so that with the + next round of the loop another block can be read. */ + size_t n; + sum = 0; + + /* Read block. Take care for partial reads. */ + while (1) + { + n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream); + + sum += n; + + if (sum == BLOCKSIZE) + break; + + if (n == 0) + { + /* Check for the error flag IFF N == 0, so that we don't + exit the loop after a partial read due to e.g., EAGAIN + or EWOULDBLOCK. */ + if (ferror (stream)) + { + free (buffer); + return 1; + } + goto process_partial_block; + } + + /* We've read at least one byte, so ignore errors. But always + check for EOF, since feof may be true even though N > 0. + Otherwise, we could end up calling fread after EOF. */ + if (feof (stream)) + goto process_partial_block; + } + + /* Process buffer with BLOCKSIZE bytes. Note that + BLOCKSIZE % 64 == 0 + */ + md4_process_block (buffer, BLOCKSIZE, &ctx); + } + +process_partial_block:; + + /* Process any remaining bytes. */ + if (sum > 0) + md4_process_bytes (buffer, sum, &ctx); + + /* Construct result in desired memory. */ + md4_finish_ctx (&ctx, resblock); + free (buffer); + return 0; +} + +/* Compute MD4 message digest for LEN bytes beginning at BUFFER. The + result is always in little endian byte order, so that a byte-wise + output yields to the wanted ASCII representation of the message + digest. */ +void * +md4_buffer (const char *buffer, size_t len, void *resblock) +{ + struct md4_ctx ctx; + + /* Initialize the computation context. */ + md4_init_ctx (&ctx); + + /* Process whole buffer but last len % 64 bytes. */ + md4_process_bytes (buffer, len, &ctx); + + /* Put result in desired memory area. */ + return md4_finish_ctx (&ctx, resblock); +} + +void +md4_process_bytes (const void *buffer, size_t len, struct md4_ctx *ctx) +{ + /* When we already have some bits in our internal buffer concatenate + both inputs first. */ + if (ctx->buflen != 0) + { + size_t left_over = ctx->buflen; + size_t add = 128 - left_over > len ? len : 128 - left_over; + + memcpy (&((char*)ctx->buffer)[left_over], buffer, add); + ctx->buflen += add; + + if (ctx->buflen > 64) + { + md4_process_block (ctx->buffer, ctx->buflen & ~63, ctx); + + ctx->buflen &= 63; + /* The regions in the following copy operation cannot overlap. */ + memcpy (ctx->buffer, &((char*)ctx->buffer)[(left_over + add) & ~63], + ctx->buflen); + } + + buffer = (const char *) buffer + add; + len -= add; + } + + /* Process available complete blocks. */ + if (len >= 64) + { +#if !(_STRING_ARCH_unaligned || _STRING_INLINE_unaligned) +# define UNALIGNED_P(p) ((uintptr_t) (p) % alignof (uint32_t) != 0) + if (UNALIGNED_P (buffer)) + while (len > 64) + { + md4_process_block (memcpy (ctx->buffer, buffer, 64), 64, ctx); + buffer = (const char *) buffer + 64; + len -= 64; + } + else +#endif + { + md4_process_block (buffer, len & ~63, ctx); + buffer = (const char *) buffer + (len & ~63); + len &= 63; + } + } + + /* Move remaining bytes in internal buffer. */ + if (len > 0) + { + size_t left_over = ctx->buflen; + + memcpy (&((char*)ctx->buffer)[left_over], buffer, len); + left_over += len; + if (left_over >= 64) + { + md4_process_block (ctx->buffer, 64, ctx); + left_over -= 64; + memcpy (ctx->buffer, &ctx->buffer[16], left_over); + } + ctx->buflen = left_over; + } +} + +/* --- Code below is the primary difference between md5.c and md4.c --- */ + +/* MD4 round constants */ +#define K1 0x5a827999 +#define K2 0x6ed9eba1 + +/* Round functions. */ +#define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z)))) +#define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z))) +#define H(x, y, z) ((x) ^ (y) ^ (z)) +#define rol(x, n) (((x) << (n)) | ((uint32_t) (x) >> (32 - (n)))) +#define R1(a,b,c,d,k,s) a=rol(a+F(b,c,d)+x[k],s); +#define R2(a,b,c,d,k,s) a=rol(a+G(b,c,d)+x[k]+K1,s); +#define R3(a,b,c,d,k,s) a=rol(a+H(b,c,d)+x[k]+K2,s); + +/* Process LEN bytes of BUFFER, accumulating context into CTX. + It is assumed that LEN % 64 == 0. */ + +void +md4_process_block (const void *buffer, size_t len, struct md4_ctx *ctx) +{ + const uint32_t *words = buffer; + size_t nwords = len / sizeof (uint32_t); + const uint32_t *endp = words + nwords; + uint32_t x[16]; + uint32_t A = ctx->A; + uint32_t B = ctx->B; + uint32_t C = ctx->C; + uint32_t D = ctx->D; + uint32_t lolen = len; + + /* First increment the byte count. RFC 1320 specifies the possible + length of the file up to 2^64 bits. Here we only compute the + number of bytes. Do a double word increment. */ + ctx->total[0] += lolen; + ctx->total[1] += (len >> 31 >> 1) + (ctx->total[0] < lolen); + + /* Process all bytes in the buffer with 64 bytes in each round of + the loop. */ + while (words < endp) + { + int t; + for (t = 0; t < 16; t++) + { + x[t] = SWAP (*words); + words++; + } + + /* Round 1. */ + R1 (A, B, C, D, 0, 3); + R1 (D, A, B, C, 1, 7); + R1 (C, D, A, B, 2, 11); + R1 (B, C, D, A, 3, 19); + R1 (A, B, C, D, 4, 3); + R1 (D, A, B, C, 5, 7); + R1 (C, D, A, B, 6, 11); + R1 (B, C, D, A, 7, 19); + R1 (A, B, C, D, 8, 3); + R1 (D, A, B, C, 9, 7); + R1 (C, D, A, B, 10, 11); + R1 (B, C, D, A, 11, 19); + R1 (A, B, C, D, 12, 3); + R1 (D, A, B, C, 13, 7); + R1 (C, D, A, B, 14, 11); + R1 (B, C, D, A, 15, 19); + + /* Round 2. */ + R2 (A, B, C, D, 0, 3); + R2 (D, A, B, C, 4, 5); + R2 (C, D, A, B, 8, 9); + R2 (B, C, D, A, 12, 13); + R2 (A, B, C, D, 1, 3); + R2 (D, A, B, C, 5, 5); + R2 (C, D, A, B, 9, 9); + R2 (B, C, D, A, 13, 13); + R2 (A, B, C, D, 2, 3); + R2 (D, A, B, C, 6, 5); + R2 (C, D, A, B, 10, 9); + R2 (B, C, D, A, 14, 13); + R2 (A, B, C, D, 3, 3); + R2 (D, A, B, C, 7, 5); + R2 (C, D, A, B, 11, 9); + R2 (B, C, D, A, 15, 13); + + /* Round 3. */ + R3 (A, B, C, D, 0, 3); + R3 (D, A, B, C, 8, 9); + R3 (C, D, A, B, 4, 11); + R3 (B, C, D, A, 12, 15); + R3 (A, B, C, D, 2, 3); + R3 (D, A, B, C, 10, 9); + R3 (C, D, A, B, 6, 11); + R3 (B, C, D, A, 14, 15); + R3 (A, B, C, D, 1, 3); + R3 (D, A, B, C, 9, 9); + R3 (C, D, A, B, 5, 11); + R3 (B, C, D, A, 13, 15); + R3 (A, B, C, D, 3, 3); + R3 (D, A, B, C, 11, 9); + R3 (C, D, A, B, 7, 11); + R3 (B, C, D, A, 15, 15); + + A = ctx->A += A; + B = ctx->B += B; + C = ctx->C += C; + D = ctx->D += D; + } +} -- cgit v1.2.3