diff options
Diffstat (limited to 'libavcodec/dxa.c')
-rw-r--r-- | libavcodec/dxa.c | 95 |
1 files changed, 62 insertions, 33 deletions
diff --git a/libavcodec/dxa.c b/libavcodec/dxa.c index fa0677d34c..0f64b5e619 100644 --- a/libavcodec/dxa.c +++ b/libavcodec/dxa.c @@ -2,20 +2,20 @@ * Feeble Files/ScummVM DXA decoder * Copyright (c) 2007 Konstantin Shishkov * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * - * Libav is distributed in the hope that it will be useful, + * FFmpeg 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -29,6 +29,7 @@ #include "libavutil/common.h" #include "libavutil/intreadwrite.h" +#include "bytestream.h" #include "avcodec.h" #include "internal.h" @@ -41,6 +42,7 @@ typedef struct DxaDecContext { AVFrame *prev; int dsize; +#define DECOMP_BUF_PADDING 16 uint8_t *decomp_buf; uint32_t pal[256]; } DxaDecContext; @@ -49,13 +51,17 @@ static const int shift1[6] = { 0, 8, 8, 8, 4, 4 }; static const int shift2[6] = { 0, 0, 8, 4, 0, 4 }; static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst, - int stride, uint8_t *src, uint8_t *ref) + int stride, uint8_t *src, int srcsize, uint8_t *ref) { uint8_t *code, *data, *mv, *msk, *tmp, *tmp2; + uint8_t *src_end = src + srcsize; int i, j, k; int type, x, y, d, d2; uint32_t mask; + if (12ULL + ((avctx->width * avctx->height) >> 4) + AV_RB32(src + 0) + AV_RB32(src + 4) > srcsize) + return AVERROR_INVALIDDATA; + code = src + 12; data = code + ((avctx->width * avctx->height) >> 4); mv = data + AV_RB32(src + 0); @@ -63,6 +69,8 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst, for(j = 0; j < avctx->height; j += 4){ for(i = 0; i < avctx->width; i += 4){ + if (data > src_end || mv > src_end || msk > src_end) + return AVERROR_INVALIDDATA; tmp = dst + i; tmp2 = ref + i; type = *code++; @@ -70,6 +78,11 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst, case 4: // motion compensation x = (*mv) >> 4; if(x & 8) x = 8 - x; y = (*mv++) & 0xF; if(y & 8) y = 8 - y; + if (i < -x || avctx->width - i - 4 < x || + j < -y || avctx->height - j - 4 < y) { + av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y); + return AVERROR_INVALIDDATA; + } tmp2 += x + y*stride; case 0: // skip case 5: // skip in method 12 @@ -127,6 +140,11 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst, case 0x80: // motion compensation x = (*mv) >> 4; if(x & 8) x = 8 - x; y = (*mv++) & 0xF; if(y & 8) y = 8 - y; + if (i + 2*(k & 1) < -x || avctx->width - i - 2*(k & 1) - 2 < x || + j + (k & 2) < -y || avctx->height - j - (k & 2) - 2 < y) { + av_log(avctx, AV_LOG_ERROR, "MV %d %d out of bounds\n", x,y); + return AVERROR_INVALIDDATA; + } tmp2 += x + y*stride; case 0x00: // skip tmp[d + 0 ] = tmp2[0]; @@ -192,35 +210,27 @@ static int decode_13(AVCodecContext *avctx, DxaDecContext *c, uint8_t* dst, static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) { AVFrame *frame = data; - const uint8_t *buf = avpkt->data; - int buf_size = avpkt->size; DxaDecContext * const c = avctx->priv_data; uint8_t *outptr, *srcptr, *tmpptr; unsigned long dsize; int i, j, compr, ret; int stride; - int orig_buf_size = buf_size; int pc = 0; + GetByteContext gb; - /* make the palette available on the way out */ - if(buf[0]=='C' && buf[1]=='M' && buf[2]=='A' && buf[3]=='P'){ - int r, g, b; + bytestream2_init(&gb, avpkt->data, avpkt->size); - buf += 4; + /* make the palette available on the way out */ + if (bytestream2_peek_le32(&gb) == MKTAG('C','M','A','P')) { + bytestream2_skip(&gb, 4); for(i = 0; i < 256; i++){ - r = *buf++; - g = *buf++; - b = *buf++; - c->pal[i] = (r << 16) | (g << 8) | b; + c->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&gb); } pc = 1; - buf_size -= 768+4; } - if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) { - av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); + if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) return ret; - } memcpy(frame->data[1], c->pal, AVPALETTE_SIZE); frame->palette_has_changed = pc; @@ -229,16 +239,25 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac tmpptr = c->prev->data[0]; stride = frame->linesize[0]; - if(buf[0]=='N' && buf[1]=='U' && buf[2]=='L' && buf[3]=='L') + if (bytestream2_get_le32(&gb) == MKTAG('N','U','L','L')) compr = -1; else - compr = buf[4]; + compr = bytestream2_get_byte(&gb); dsize = c->dsize; - if((compr != 4 && compr != -1) && uncompress(c->decomp_buf, &dsize, buf + 9, buf_size - 9) != Z_OK){ - av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n"); - return AVERROR_UNKNOWN; + if (compr != 4 && compr != -1) { + bytestream2_skip(&gb, 4); + if (uncompress(c->decomp_buf, &dsize, avpkt->data + bytestream2_tell(&gb), + bytestream2_get_bytes_left(&gb)) != Z_OK) { + av_log(avctx, AV_LOG_ERROR, "Uncompress failed!\n"); + return AVERROR_UNKNOWN; + } + memset(c->decomp_buf + dsize, 0, DECOMP_BUF_PADDING); } + + if (avctx->debug & FF_DEBUG_PICT_INFO) + av_log(avctx, AV_LOG_DEBUG, "compr:%2d, dsize:%d\n", compr, (int)dsize); + switch(compr){ case -1: frame->key_frame = 0; @@ -265,14 +284,18 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac case 5: if (!tmpptr) { av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n"); - return AVERROR_INVALIDDATA; + if (!(avctx->flags2 & CODEC_FLAG2_SHOW_ALL)) + return AVERROR_INVALIDDATA; } frame->key_frame = 0; frame->pict_type = AV_PICTURE_TYPE_P; for (j = 0; j < avctx->height; j++) { - for (i = 0; i < avctx->width; i++) - outptr[i] = srcptr[i] ^ tmpptr[i]; - tmpptr += stride; + if(tmpptr){ + for(i = 0; i < avctx->width; i++) + outptr[i] = srcptr[i] ^ tmpptr[i]; + tmpptr += stride; + }else + memcpy(outptr, srcptr, avctx->width); outptr += stride; srcptr += avctx->width; } @@ -281,10 +304,14 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac case 13: frame->key_frame = 0; frame->pict_type = AV_PICTURE_TYPE_P; - decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, c->prev->data[0]); + if (!c->prev->data[0]) { + av_log(avctx, AV_LOG_ERROR, "Missing reference frame\n"); + return AVERROR_INVALIDDATA; + } + decode_13(avctx, c, frame->data[0], frame->linesize[0], srcptr, dsize, c->prev->data[0]); break; default: - av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", buf[4]); + av_log(avctx, AV_LOG_ERROR, "Unknown/unsupported compression type %d\n", compr); return AVERROR_INVALIDDATA; } @@ -295,7 +322,7 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac *got_frame = 1; /* always report that the buffer was completely consumed */ - return orig_buf_size; + return avpkt->size; } static av_cold int decode_init(AVCodecContext *avctx) @@ -309,7 +336,9 @@ static av_cold int decode_init(AVCodecContext *avctx) avctx->pix_fmt = AV_PIX_FMT_PAL8; c->dsize = avctx->width * avctx->height * 2; - if((c->decomp_buf = av_malloc(c->dsize)) == NULL) { + c->decomp_buf = av_malloc(c->dsize + DECOMP_BUF_PADDING); + if (!c->decomp_buf) { + av_frame_free(&c->prev); av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n"); return AVERROR(ENOMEM); } |