1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "content/browser/download/file_metadata_mac.h" 6 7 #include <ApplicationServices/ApplicationServices.h> 8 #include <Foundation/Foundation.h> 9 10 #include "base/files/file_path.h" 11 #include "base/logging.h" 12 #include "base/mac/mac_logging.h" 13 #include "base/mac/mac_util.h" 14 #include "base/mac/scoped_cftyperef.h" 15 #include "url/gurl.h" 16 17 namespace content { 18 19 // As of Mac OS X 10.4 ("Tiger"), files can be tagged with metadata describing 20 // various attributes. Metadata is integrated with the system's Spotlight 21 // feature and is searchable. Ordinarily, metadata can only be set by 22 // Spotlight importers, which requires that the importer own the target file. 23 // However, there's an attribute intended to describe the origin of a 24 // file, that can store the source URL and referrer of a downloaded file. 25 // It's stored as a "com.apple.metadata:kMDItemWhereFroms" extended attribute, 26 // structured as a binary1-format plist containing a list of sources. This 27 // attribute can only be populated by the downloader, not a Spotlight importer. 28 // Safari on 10.4 and later populates this attribute. 29 // 30 // With this metadata set, you can locate downloads by performing a Spotlight 31 // search for their source or referrer URLs, either from within the Spotlight 32 // UI or from the command line: 33 // mdfind 'kMDItemWhereFroms == "http://releases.mozilla.org/*"' 34 // 35 // There is no documented API to set metadata on a file directly as of the 36 // 10.5 SDK. The MDSetItemAttribute function does exist to perform this task, 37 // but it's undocumented. 38 void AddOriginMetadataToFile(const base::FilePath& file, const GURL& source, 39 const GURL& referrer) { 40 // There's no declaration for MDItemSetAttribute in any known public SDK. 41 // It exists in the 10.4 and 10.5 runtimes. To play it safe, do the lookup 42 // at runtime instead of declaring it ourselves and linking against what's 43 // provided. This has two benefits: 44 // - If Apple relents and declares the function in a future SDK (it's 45 // happened before), our build won't break. 46 // - If Apple removes or renames the function in a future runtime, the 47 // loader won't refuse to let the application launch. Instead, we'll 48 // silently fail to set any metadata. 49 typedef OSStatus (*MDItemSetAttribute_type)(MDItemRef, CFStringRef, 50 CFTypeRef); 51 static MDItemSetAttribute_type md_item_set_attribute_func = NULL; 52 53 static bool did_symbol_lookup = false; 54 if (!did_symbol_lookup) { 55 did_symbol_lookup = true; 56 CFBundleRef metadata_bundle = 57 CFBundleGetBundleWithIdentifier(CFSTR("com.apple.Metadata")); 58 if (!metadata_bundle) 59 return; 60 61 md_item_set_attribute_func = (MDItemSetAttribute_type) 62 CFBundleGetFunctionPointerForName(metadata_bundle, 63 CFSTR("MDItemSetAttribute")); 64 } 65 if (!md_item_set_attribute_func) 66 return; 67 68 NSString* file_path = 69 [NSString stringWithUTF8String:file.value().c_str()]; 70 if (!file_path) 71 return; 72 73 base::ScopedCFTypeRef<MDItemRef> md_item( 74 MDItemCreate(NULL, base::mac::NSToCFCast(file_path))); 75 if (!md_item) 76 return; 77 78 // We won't put any more than 2 items into the attribute. 79 NSMutableArray* list = [NSMutableArray arrayWithCapacity:2]; 80 81 // Follow Safari's lead: the first item in the list is the source URL of 82 // the downloaded file. If the referrer is known, store that, too. 83 NSString* origin_url = [NSString stringWithUTF8String:source.spec().c_str()]; 84 if (origin_url) 85 [list addObject:origin_url]; 86 NSString* referrer_url = 87 [NSString stringWithUTF8String:referrer.spec().c_str()]; 88 if (referrer_url) 89 [list addObject:referrer_url]; 90 91 md_item_set_attribute_func(md_item, kMDItemWhereFroms, 92 base::mac::NSToCFCast(list)); 93 } 94 95 // The OS will automatically quarantine files due to the 96 // LSFileQuarantineEnabled entry in our Info.plist, but it knows relatively 97 // little about the files. We add more information about the download to 98 // improve the UI shown by the OS when the users tries to open the file. 99 void AddQuarantineMetadataToFile(const base::FilePath& file, const GURL& source, 100 const GURL& referrer) { 101 FSRef file_ref; 102 if (!base::mac::FSRefFromPath(file.value(), &file_ref)) 103 return; 104 105 NSMutableDictionary* quarantine_properties = nil; 106 CFTypeRef quarantine_properties_base = NULL; 107 if (LSCopyItemAttribute(&file_ref, kLSRolesAll, kLSItemQuarantineProperties, 108 &quarantine_properties_base) == noErr) { 109 if (CFGetTypeID(quarantine_properties_base) == 110 CFDictionaryGetTypeID()) { 111 // Quarantine properties will already exist if LSFileQuarantineEnabled 112 // is on and the file doesn't match an exclusion. 113 quarantine_properties = 114 [[(NSDictionary*)quarantine_properties_base mutableCopy] autorelease]; 115 } else { 116 LOG(WARNING) << "kLSItemQuarantineProperties is not a dictionary on file " 117 << file.value(); 118 } 119 CFRelease(quarantine_properties_base); 120 } 121 122 if (!quarantine_properties) { 123 // If there are no quarantine properties, then the file isn't quarantined 124 // (e.g., because the user has set up exclusions for certain file types). 125 // We don't want to add any metadata, because that will cause the file to 126 // be quarantined against the user's wishes. 127 return; 128 } 129 130 // kLSQuarantineAgentNameKey, kLSQuarantineAgentBundleIdentifierKey, and 131 // kLSQuarantineTimeStampKey are set for us (see LSQuarantine.h), so we only 132 // need to set the values that the OS can't infer. 133 134 if (![quarantine_properties valueForKey:(NSString*)kLSQuarantineTypeKey]) { 135 CFStringRef type = source.SchemeIsHTTPOrHTTPS() 136 ? kLSQuarantineTypeWebDownload 137 : kLSQuarantineTypeOtherDownload; 138 [quarantine_properties setValue:(NSString*)type 139 forKey:(NSString*)kLSQuarantineTypeKey]; 140 } 141 142 if (![quarantine_properties 143 valueForKey:(NSString*)kLSQuarantineOriginURLKey] && 144 referrer.is_valid()) { 145 NSString* referrer_url = 146 [NSString stringWithUTF8String:referrer.spec().c_str()]; 147 [quarantine_properties setValue:referrer_url 148 forKey:(NSString*)kLSQuarantineOriginURLKey]; 149 } 150 151 if (![quarantine_properties valueForKey:(NSString*)kLSQuarantineDataURLKey] && 152 source.is_valid()) { 153 NSString* origin_url = 154 [NSString stringWithUTF8String:source.spec().c_str()]; 155 [quarantine_properties setValue:origin_url 156 forKey:(NSString*)kLSQuarantineDataURLKey]; 157 } 158 159 OSStatus os_error = LSSetItemAttribute(&file_ref, kLSRolesAll, 160 kLSItemQuarantineProperties, 161 quarantine_properties); 162 if (os_error != noErr) { 163 OSSTATUS_LOG(WARNING, os_error) 164 << "Unable to set quarantine attributes on file " << file.value(); 165 } 166 } 167 168 } // namespace content 169
