diff --git a/lib/zip_close.c b/lib/zip_close.c
index 4313592cd..decc5d65a 100644
--- a/lib/zip_close.c
+++ b/lib/zip_close.c
@@ -295,8 +295,7 @@ zip_close(zip_t *za) {
 }
 
 
-static int
-add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, zip_uint32_t changed) {
+static int add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, zip_uint32_t changed) {
     zip_int64_t offstart, offdata, offend, data_length;
     zip_stat_t st;
     zip_file_attributes_t attributes;
@@ -305,19 +304,24 @@ add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, zip_uint32_t changed) {
     int is_zip64;
     zip_flags_t flags;
     bool needs_recompress, needs_decompress, needs_crc, needs_compress, needs_reencrypt, needs_decrypt, needs_encrypt;
+    bool have_dos_time, dirent_changed;
+    time_t mtime_before_copy;
 
     if (zip_source_stat(src, &st) < 0) {
         zip_error_set_from_source(&za->error, src);
         return -1;
     }
 
+    de->bitflags &= ~ZIP_GPBF_DATA_DESCRIPTOR;
+
     if ((st.valid & ZIP_STAT_COMP_METHOD) == 0) {
         st.valid |= ZIP_STAT_COMP_METHOD;
         st.comp_method = ZIP_CM_STORE;
     }
 
-    if (ZIP_CM_IS_DEFAULT(de->comp_method) && st.comp_method != ZIP_CM_STORE)
+    if (ZIP_CM_IS_DEFAULT(de->comp_method) && st.comp_method != ZIP_CM_STORE) {
         de->comp_method = st.comp_method;
+    }
     else if (de->comp_method == ZIP_CM_STORE && (st.valid & ZIP_STAT_SIZE)) {
         st.valid |= ZIP_STAT_COMP_SIZE;
         st.comp_size = st.size;
@@ -372,14 +376,30 @@ add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, zip_uint32_t changed) {
         }
     }
 
-    if ((offstart = zip_source_tell_write(za->src)) < 0) {
-        zip_error_set_from_source(&za->error, za->src);
-        return -1;
+    if ((de->changed & ZIP_DIRENT_LAST_MOD) == 0) {
+        int ret2 = zip_source_get_dos_time(src, &de->last_mod);
+        if (ret2 < 0) {
+            zip_error_set_from_source(&za->error, src);
+            return -1;
+        }
+        if (ret2 == 1) {
+            have_dos_time = true;
+        }
+        else {
+            if (st.valid & ZIP_STAT_MTIME) {
+                mtime_before_copy = st.mtime;
+            }
+            else {
+                time(&mtime_before_copy);
+            }
+            if (_zip_u2d_time(mtime_before_copy, &de->last_mod, &za->error) < 0) {
+                return -1;
+            }
+        }
     }
 
-    /* as long as we don't support non-seekable output, clear data descriptor bit */
-    de->bitflags &= (zip_uint16_t)~ZIP_GPBF_DATA_DESCRIPTOR;
-    if ((is_zip64 = _zip_dirent_write(za, de, flags)) < 0) {
+    if ((offstart = zip_source_tell_write(za->src)) < 0) {
+        zip_error_set_from_source(&za->error, za->src);
         return -1;
     }
 
@@ -485,6 +505,18 @@ add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, zip_uint32_t changed) {
         src_final = src_tmp;
     }
 
+    if (!ZIP_WANT_TORRENTZIP(za)) {
+        if (zip_source_get_file_attributes(src_final, &attributes) != 0) {
+            zip_error_set_from_source(&za->error, src_final);
+            ret = -1;
+        }
+        _zip_dirent_apply_attributes(de, &attributes, (flags & ZIP_FL_FORCE_ZIP64) != 0, changed);
+    }
+
+    /* as long as we don't support non-seekable output, clear data descriptor bit */
+    if ((is_zip64 = _zip_dirent_write(za, de, flags)) < 0) {
+        return -1;
+    }
 
     if ((offdata = zip_source_tell_write(za->src)) < 0) {
         zip_error_set_from_source(&za->error, za->src);
@@ -498,9 +530,11 @@ add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, zip_uint32_t changed) {
         ret = -1;
     }
 
-    if (zip_source_get_file_attributes(src_final, &attributes) != 0) {
-        zip_error_set_from_source(&za->error, src_final);
-        ret = -1;
+    if (!ZIP_WANT_TORRENTZIP(za)) {
+        if (zip_source_get_file_attributes(src_final, &attributes) != 0) {
+            zip_error_set_from_source(&za->error, src_final);
+            ret = -1;
+        }
     }
 
     zip_source_free(src_final);
@@ -514,57 +548,51 @@ add_data(zip_t *za, zip_source_t *src, zip_dirent_t *de, zip_uint32_t changed) {
         return -1;
     }
 
-    if (zip_source_seek_write(za->src, offstart, SEEK_SET) < 0) {
-        zip_error_set_from_source(&za->error, za->src);
-        return -1;
-    }
-
     if ((st.valid & (ZIP_STAT_COMP_METHOD | ZIP_STAT_CRC | ZIP_STAT_SIZE)) != (ZIP_STAT_COMP_METHOD | ZIP_STAT_CRC | ZIP_STAT_SIZE)) {
         zip_error_set(&za->error, ZIP_ER_INTERNAL, 0);
         return -1;
     }
 
-    if ((de->changed & ZIP_DIRENT_LAST_MOD) == 0) {
-        int ret2 = zip_source_get_dos_time(src, &de->last_mod);
-        if (ret2 < 0) {
-            zip_error_set_from_source(&za->error, src);
-            return -1;
-        }
-        if (ret2 == 0) {
-            time_t mtime;
-            if (st.valid & ZIP_STAT_MTIME) {
-                mtime = st.mtime;
-            }
-            else {
-                time(&mtime);
-            }
-            if (_zip_u2d_time(mtime, &de->last_mod, &za->error) < 0) {
-                return -1;
-            }
-        }
-    }
+    dirent_changed = ZIP_CM_ACTUAL(de->comp_method) != st.comp_method || de->crc != st.crc || de->uncomp_size != st.size || de->comp_size != (zip_uint64_t)(offend - offdata);
     de->comp_method = st.comp_method;
     de->crc = st.crc;
     de->uncomp_size = st.size;
     de->comp_size = (zip_uint64_t)(offend - offdata);
-    _zip_dirent_apply_attributes(de, &attributes, (flags & ZIP_FL_FORCE_ZIP64) != 0, changed);
 
-    if (ZIP_WANT_TORRENTZIP(za)) {
-        zip_dirent_torrentzip_normalize(de);
+    if (!ZIP_WANT_TORRENTZIP(za)) {
+        dirent_changed |= _zip_dirent_apply_attributes(de, &attributes, (flags & ZIP_FL_FORCE_ZIP64) != 0, changed);
+
+        if ((de->changed & ZIP_DIRENT_LAST_MOD) == 0 && !have_dos_time) {
+            if (st.valid & ZIP_STAT_MTIME) {
+                if (st.mtime != mtime_before_copy) {
+                    if (_zip_u2d_time(st.mtime, &de->last_mod, &za->error) < 0) {
+                        return -1;
+                    }
+                    dirent_changed = true;
+                }
+            }
+        }
     }
 
-    if ((ret = _zip_dirent_write(za, de, flags)) < 0)
-        return -1;
+    if (dirent_changed) {
+        if (zip_source_seek_write(za->src, offstart, SEEK_SET) < 0) {
+            zip_error_set_from_source(&za->error, za->src);
+            return -1;
+        }
 
-    if (is_zip64 != ret) {
-        /* Zip64 mismatch between preliminary file header written before data and final file header written afterwards */
-        zip_error_set(&za->error, ZIP_ER_INTERNAL, 0);
-        return -1;
-    }
+        if ((ret = _zip_dirent_write(za, de, flags)) < 0)
+            return -1;
 
-    if (zip_source_seek_write(za->src, offend, SEEK_SET) < 0) {
-        zip_error_set_from_source(&za->error, za->src);
-        return -1;
+        if (is_zip64 != ret) {
+            /* Zip64 mismatch between preliminary file header written before data and final file header written afterwards */
+            zip_error_set(&za->error, ZIP_ER_INTERNAL, 0);
+            return -1;
+        }
+
+        if (zip_source_seek_write(za->src, offend, SEEK_SET) < 0) {
+            zip_error_set_from_source(&za->error, za->src);
+            return -1;
+        }
     }
 
     if (de->bitflags & ZIP_GPBF_DATA_DESCRIPTOR) {
diff --git a/lib/zip_dirent.c b/lib/zip_dirent.c
index 24bc6abf9..418546acc 100644
--- a/lib/zip_dirent.c
+++ b/lib/zip_dirent.c
@@ -968,7 +968,7 @@ _zip_dirent_write(zip_t *za, zip_dirent_t *de, zip_flags_t flags) {
         _zip_buffer_put_16(buffer, ZIP_CM_WINZIP_AES);
     }
     else {
-        _zip_buffer_put_16(buffer, (zip_uint16_t)de->comp_method);
+        _zip_buffer_put_16(buffer, (zip_uint16_t)ZIP_CM_ACTUAL(de->comp_method));
     }
 
     if (ZIP_WANT_TORRENTZIP(za)) {
@@ -1190,52 +1190,75 @@ _zip_u2d_time(time_t intime, zip_dostime_t *dtime, zip_error_t *ze) {
 }
 
 
-void
-_zip_dirent_apply_attributes(zip_dirent_t *de, zip_file_attributes_t *attributes, bool force_zip64, zip_uint32_t changed) {
+bool _zip_dirent_apply_attributes(zip_dirent_t *de, zip_file_attributes_t *attributes, bool force_zip64, zip_uint32_t changed) {
     zip_uint16_t length;
+    bool has_changed = false;
 
     if (attributes->valid & ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS) {
         zip_uint16_t mask = attributes->general_purpose_bit_mask & ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS_ALLOWED_MASK;
-        de->bitflags = (de->bitflags & ~mask) | (attributes->general_purpose_bit_flags & mask);
+        zip_uint16_t bitflags = (de->bitflags & ~mask) | (attributes->general_purpose_bit_flags & mask);
+        if (de->bitflags != bitflags) {
+            de->bitflags = bitflags;
+            has_changed = true;
+        }
     }
     if (attributes->valid & ZIP_FILE_ATTRIBUTES_ASCII) {
-        de->int_attrib = (de->int_attrib & ~0x1) | (attributes->ascii ? 1 : 0);
+        zip_uint16_t int_attrib = (de->int_attrib & ~0x1) | (attributes->ascii ? 1 : 0);
+        if (de->int_attrib != int_attrib) {
+            de->int_attrib = int_attrib;
+            has_changed = true;
+        }
     }
     /* manually set attributes are preferred over attributes provided by source */
     if ((changed & ZIP_DIRENT_ATTRIBUTES) == 0 && (attributes->valid & ZIP_FILE_ATTRIBUTES_EXTERNAL_FILE_ATTRIBUTES)) {
-        de->ext_attrib = attributes->external_file_attributes;
+        if (de->ext_attrib != attributes->external_file_attributes) {
+            de->ext_attrib = attributes->external_file_attributes;
+            has_changed = true;
+        }
     }
 
+    zip_uint16_t version_needed;
     if (de->comp_method == ZIP_CM_LZMA) {
-        de->version_needed = 63;
+        version_needed = 63;
     }
     else if (de->encryption_method == ZIP_EM_AES_128 || de->encryption_method == ZIP_EM_AES_192 || de->encryption_method == ZIP_EM_AES_256) {
-        de->version_needed = 51;
+        version_needed = 51;
     }
     else if (de->comp_method == ZIP_CM_BZIP2) {
-        de->version_needed = 46;
+        version_needed = 46;
     }
     else if (force_zip64 || _zip_dirent_needs_zip64(de, 0)) {
-        de->version_needed = 45;
+        version_needed = 45;
     }
     else if (de->comp_method == ZIP_CM_DEFLATE || de->encryption_method == ZIP_EM_TRAD_PKWARE) {
-        de->version_needed = 20;
+        version_needed = 20;
     }
     else if ((length = _zip_string_length(de->filename)) > 0 && de->filename->raw[length - 1] == '/') {
-        de->version_needed = 20;
+        version_needed = 20;
     }
     else {
-        de->version_needed = 10;
+        version_needed = 10;
     }
 
     if (attributes->valid & ZIP_FILE_ATTRIBUTES_VERSION_NEEDED) {
-        de->version_needed = ZIP_MAX(de->version_needed, attributes->version_needed);
+        version_needed = ZIP_MAX(version_needed, attributes->version_needed);
     }
 
-    de->version_madeby = 63 | (de->version_madeby & 0xff00);
+    if (de->version_needed != version_needed) {
+        de->version_needed = version_needed;
+        has_changed = true;
+    }
+
+    zip_int16_t version_madeby = 63 | (de->version_madeby & 0xff00);
     if ((changed & ZIP_DIRENT_ATTRIBUTES) == 0 && (attributes->valid & ZIP_FILE_ATTRIBUTES_HOST_SYSTEM)) {
-        de->version_madeby = (de->version_madeby & 0xff) | (zip_uint16_t)(attributes->host_system << 8);
+        version_madeby = (version_madeby & 0xff) | (zip_uint16_t)(attributes->host_system << 8);
+    }
+    if (de->version_madeby != version_madeby) {
+        de->version_madeby = version_madeby;
+        has_changed = true;
     }
+
+    return has_changed;
 }
 
 
@@ -1265,7 +1288,8 @@ zip_dirent_check_consistency(zip_dirent_t *dirent) {
     return 0;
 }
 
-time_t zip_dirent_get_last_mod_mtime(zip_dirent_t *de) {
+time_t
+zip_dirent_get_last_mod_mtime(zip_dirent_t *de) {
     if (!de->last_mod_mtime_valid) {
         de->last_mod_mtime = _zip_d2u_time(&de->last_mod);
         de->last_mod_mtime_valid = true;
diff --git a/lib/zip_source_get_file_attributes.c b/lib/zip_source_get_file_attributes.c
index 209e39f50..59c064fe0 100644
--- a/lib/zip_source_get_file_attributes.c
+++ b/lib/zip_source_get_file_attributes.c
@@ -39,8 +39,7 @@ zip_file_attributes_init(zip_file_attributes_t *attributes) {
     attributes->version = 1;
 }
 
-int
-zip_source_get_file_attributes(zip_source_t *src, zip_file_attributes_t *attributes) {
+int zip_source_get_file_attributes(zip_source_t *src, zip_file_attributes_t *attributes) {
     if (src->source_closed) {
         return -1;
     }
diff --git a/lib/zip_source_pkware_encode.c b/lib/zip_source_pkware_encode.c
index fed76115b..26e1ce794 100644
--- a/lib/zip_source_pkware_encode.c
+++ b/lib/zip_source_pkware_encode.c
@@ -198,8 +198,10 @@ pkware_encrypt(zip_source_t *src, void *ud, void *data, zip_uint64_t length, zip
             zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
             return -1;
         }
-        attributes->valid |= ZIP_FILE_ATTRIBUTES_VERSION_NEEDED;
+        attributes->valid |= ZIP_FILE_ATTRIBUTES_VERSION_NEEDED | ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS;
         attributes->version_needed = 20;
+        attributes->general_purpose_bit_flags = ZIP_GPBF_DATA_DESCRIPTOR;
+        attributes->general_purpose_bit_mask = ZIP_GPBF_DATA_DESCRIPTOR;
 
         return 0;
     }
diff --git a/lib/zipint.h b/lib/zipint.h
index e22d74c21..701f4e1de 100644
--- a/lib/zipint.h
+++ b/lib/zipint.h
@@ -102,7 +102,8 @@
 /* according to unzip-6.0's zipinfo.c, this corresponds to a directory with rwx permissions for everyone */
 #define ZIP_EXT_ATTRIB_DEFAULT_DIR (0040777u << 16)
 
-#define ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS_ALLOWED_MASK 0x0836
+/* Allowed: Encryption specific bits, data descriptor, compression specific, UTF-8 filename */
+#define ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS_ALLOWED_MASK 0x083e
 
 #define ZIP_MAX(a, b) ((a) > (b) ? (a) : (b))
 #define ZIP_MIN(a, b) ((a) < (b) ? (a) : (b))
@@ -552,7 +553,7 @@ zip_int64_t _zip_cdir_write(zip_t *za, const zip_filelist_t *filelist, zip_uint6
 time_t _zip_d2u_time(const zip_dostime_t*);
 void _zip_deregister_source(zip_t *za, zip_source_t *src);
 
-void _zip_dirent_apply_attributes(zip_dirent_t *, zip_file_attributes_t *, bool, zip_uint32_t);
+bool _zip_dirent_apply_attributes(zip_dirent_t *, zip_file_attributes_t *, bool, zip_uint32_t);
 int zip_dirent_check_consistency(zip_dirent_t *dirent);
 zip_dirent_t *_zip_dirent_clone(const zip_dirent_t *);
 void _zip_dirent_free(zip_dirent_t *);