From 9117213313f589627c3760bc66412c337ee2179d Mon Sep 17 00:00:00 2001 From: Kostya Shishkov Date: Wed, 16 Sep 2009 04:43:33 +0000 Subject: Enhance Musepack SV8 probing code Originally committed as revision 19874 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/mpc8.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) (limited to 'libavformat/mpc8.c') diff --git a/libavformat/mpc8.c b/libavformat/mpc8.c index 687853bcde..284d8d1e47 100644 --- a/libavformat/mpc8.c +++ b/libavformat/mpc8.c @@ -53,9 +53,35 @@ typedef struct { static int mpc8_probe(AVProbeData *p) { - if (AV_RL32(p->buf) == TAG_MPCK) + if (p->buf_size < 16) + return 0; + if (AV_RL32(p->buf) != TAG_MPCK) + return 0; + if (p->buf[4] == 'S' && p->buf[5] == 'H') { + int size = p->buf[6]; + + if (size < 12 || size > 30) + return 0; + if (!AV_RL32(&p->buf[7])) //zero CRC is invalid + return 0; + //check whether some tag follows stream header or not + if (p->buf[4 + size] < 'A' || p->buf[4 + size] > 'Z') + return 0; + if (p->buf[5 + size] < 'A' || p->buf[5 + size] > 'Z') + return 0; + if (p->buf[6 + size] < 3) + return 0; return AVPROBE_SCORE_MAX; - return 0; + } + /* file magic number should be followed by tag name which consists of + two uppercase letters */ + if (p->buf[4] < 'A' || p->buf[4] > 'Z' || p->buf[5] < 'A' || p->buf[5] > 'Z') + return 0; + // tag size should be >= 3 + if (p->buf[6] < 3) + return 0; + // if first tag is not stream header, that's suspicious + return AVPROBE_SCORE_MAX / 4; } static inline int64_t gb_get_v(GetBitContext *gb) -- cgit v1.2.3