[FFmpeg-devel] [PATCH 1/2 v2] avformat/dashdec: enable overriding of the maximum manifest size

[Jan Ekström]

This enables people to override the sanity check without compiling
a new binary.
---
 libavformat/dashdec.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/libavformat/dashdec.c b/libavformat/dashdec.c
index c5a5ff607b..4080b9b650 100644
--- a/libavformat/dashdec.c
+++ b/libavformat/dashdec.c
@@ -160,6 +160,7 @@ typedef struct DASHContext {
     int is_init_section_common_video;
     int is_init_section_common_audio;
 
+    uint64_t maximum_manifest_size;
 } DASHContext;
 
 static int ishttp(char *url)
@@ -1256,14 +1257,21 @@ static int parse_manifest(AVFormatContext *s, const char *url, AVIOContext *in)
     }
 
     filesize = avio_size(in);
-    if (filesize > MAX_MANIFEST_SIZE) {
-        av_log(s, AV_LOG_ERROR, "Manifest too large: %"PRId64"\n", filesize);
+    if (c->maximum_manifest_size && filesize > c->maximum_manifest_size) {
+        av_log(s, AV_LOG_ERROR,
+               "Manifest size too large: %"PRId64" (this sanity check can be "
+               "adjusted by using the option 'maximum_manifest_size')\n",
+               filesize);
         return AVERROR_INVALIDDATA;
     }
 
     av_bprint_init(&buf, (filesize > 0) ? filesize + 1 : DEFAULT_MANIFEST_SIZE, AV_BPRINT_SIZE_UNLIMITED);
 
-    if ((ret = avio_read_to_bprint(in, &buf, MAX_MANIFEST_SIZE)) < 0 ||
+    if ((ret = avio_read_to_bprint(in, &buf,
+                                   c->maximum_manifest_size > 0 ?
+                                   c->maximum_manifest_size :
+                                   (filesize > MAX_MANIFEST_SIZE ?
+                                    filesize : MAX_MANIFEST_SIZE))) < 0 ||
         !avio_feof(in) ||
         (filesize = buf.len) == 0) {
         av_log(s, AV_LOG_ERROR, "Unable to read to manifest '%s'\n", url);
@@ -2409,6 +2417,9 @@ static const AVOption dash_options[] = {
         OFFSET(allowed_extensions), AV_OPT_TYPE_STRING,
         {.str = "aac,m4a,m4s,m4v,mov,mp4,webm,ts"},
         INT_MIN, INT_MAX, FLAGS},
+    {"maximum_manifest_size", "Maximum allowed size of the MPEG-DASH manifest to read in bytes",
+     OFFSET(maximum_manifest_size), AV_OPT_TYPE_UINT64, {.i64 = MAX_MANIFEST_SIZE},
+     0, UINT64_MAX, FLAGS},
     {NULL}
 };
 
-- 
2.26.2