[FFmpeg-devel] [PATCH] Percent-encode URL paths in HLS playlists

[Timothy Allen]

This commit closes trac ticket 10679.

Signed-off-by: Timothy Allen <tim at treehouse.org.za>
---
 libavformat/hls.c |  9 +++++++++
 libavformat/url.c | 35 +++++++++++++++++++++++++++++++++++
 libavformat/url.h |  9 +++++++++
 3 files changed, 53 insertions(+)

diff --git a/libavformat/hls.c b/libavformat/hls.c
index c7b655c83c..49436d8184 100644
--- a/libavformat/hls.c
+++ b/libavformat/hls.c
@@ -1021,6 +1021,15 @@ static int parse_playlist(HLSContext *c, const char *url,
                     seg->key = NULL;
                 }
 
+                ff_percent_encode_url(tmp_str, sizeof(tmp_str), line);
+                if (!tmp_str[0]) {
+                    ret = AVERROR_INVALIDDATA;
+                    if (seg->key)
+                        av_free(seg->key);
+                    av_free(seg);
+                    goto fail;
+                }
+                strcpy(line, av_strdup(tmp_str));
                 ff_make_absolute_url(tmp_str, sizeof(tmp_str), url, line);
                 if (!tmp_str[0]) {
                     ret = AVERROR_INVALIDDATA;
diff --git a/libavformat/url.c b/libavformat/url.c
index d5dd6a4666..69d68d4248 100644
--- a/libavformat/url.c
+++ b/libavformat/url.c
@@ -324,6 +324,41 @@ int ff_make_absolute_url(char *buf, int size, const char *base,
     return ff_make_absolute_url2(buf, size, base, rel, HAVE_DOS_PATHS);
 }
 
+int ff_percent_encode_url(char *buf, int size, const char *url)
+{
+    const char *hex = "0123456789abcdef";
+
+    av_assert0(url);
+
+    int p = 0;
+    int len = strlen(url);
+    for (int i = 0; i < len; i++) {
+        if (i + 1 < len && ':' == url[i] && '/' == url[i+1])
+            buf[p++] = url[i];
+        else if (('a' <= url[i] && url[i] <= 'z')
+          || ('A' <= url[i] && url[i] <= 'Z')
+          || ('0' <= url[i] && url[i] <= '9')
+          || '/' == url[i] || '.' == url[i] || '~' == url[i]
+          || '-' == url[i] || '_' == url[i] || '+' == url[i]
+          || '?' == url[i] || '=' == url[i] || '&' == url[i]
+          || '#' == url[i])
+        {
+            buf[p++] = url[i];
+        } else if (' ' == url[i])
+        {
+            buf[p++] = '+';
+        } else
+        {
+            buf[p++] = '%';
+            buf[p++] = hex[url[i] >> 4];
+            buf[p++] = hex[url[i] & 15];
+            }
+    }
+    buf[p] = '\0';
+
+    return 0;
+}
+
 AVIODirEntry *ff_alloc_dir_entry(void)
 {
     AVIODirEntry *entry = av_mallocz(sizeof(AVIODirEntry));
diff --git a/libavformat/url.h b/libavformat/url.h
index 0784d77b64..85f94f06ce 100644
--- a/libavformat/url.h
+++ b/libavformat/url.h
@@ -331,6 +331,15 @@ int ff_make_absolute_url2(char *buf, int size, const char *base,
 int ff_make_absolute_url(char *buf, int size, const char *base,
                          const char *rel);
 
+/**
+ * Percent-encode a URL, to avoid it being incorrectly parsed.
+ *
+ * @param buf the buffer where output absolute url is written
+ * @param size the size of buf
+ * @param url the url to encode
+ */
+int ff_percent_encode_url(char *buf, int size, const char *url);
+
 /**
  * Allocate directory entry with default values.
  *
-- 
2.43.0