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 "sync/internal_api/syncapi_internal.h"
6
7 #include "base/memory/scoped_ptr.h"
8 #include "sync/protocol/attachments.pb.h"
9 #include "sync/protocol/password_specifics.pb.h"
10 #include "sync/protocol/sync.pb.h"
11 #include "sync/util/cryptographer.h"
12
13 namespace syncer {
14
15 namespace {
16
EndsWithSpace(const std::string & string)17 bool EndsWithSpace(const std::string& string) {
18 return !string.empty() && *string.rbegin() == ' ';
19 }
20
21 }
22
DecryptPasswordSpecifics(const sync_pb::EntitySpecifics & specifics,Cryptographer * crypto)23 sync_pb::PasswordSpecificsData* DecryptPasswordSpecifics(
24 const sync_pb::EntitySpecifics& specifics, Cryptographer* crypto) {
25 if (!specifics.has_password())
26 return NULL;
27 const sync_pb::PasswordSpecifics& password_specifics = specifics.password();
28 if (!password_specifics.has_encrypted())
29 return NULL;
30 const sync_pb::EncryptedData& encrypted = password_specifics.encrypted();
31 scoped_ptr<sync_pb::PasswordSpecificsData> data(
32 new sync_pb::PasswordSpecificsData);
33 if (!crypto->Decrypt(encrypted, data.get()))
34 return NULL;
35 return data.release();
36 }
37
38 // The list of names which are reserved for use by the server.
39 static const char* kForbiddenServerNames[] = { "", ".", ".." };
40
41 // When taking a name from the syncapi, append a space if it matches the
42 // pattern of a server-illegal name followed by zero or more spaces.
SyncAPINameToServerName(const std::string & syncer_name,std::string * out)43 void SyncAPINameToServerName(const std::string& syncer_name,
44 std::string* out) {
45 *out = syncer_name;
46 if (IsNameServerIllegalAfterTrimming(*out))
47 out->append(" ");
48 }
49
50 // In the reverse direction, if a server name matches the pattern of a
51 // server-illegal name followed by one or more spaces, remove the trailing
52 // space.
ServerNameToSyncAPIName(const std::string & server_name,std::string * out)53 void ServerNameToSyncAPIName(const std::string& server_name,
54 std::string* out) {
55 CHECK(out);
56 int length_to_copy = server_name.length();
57 if (IsNameServerIllegalAfterTrimming(server_name) &&
58 EndsWithSpace(server_name)) {
59 --length_to_copy;
60 }
61 *out = server_name.substr(0, length_to_copy);
62 }
63
64 // Checks whether |name| is a server-illegal name followed by zero or more space
65 // characters. The three server-illegal names are the empty string, dot, and
66 // dot-dot. Very long names (>255 bytes in UTF-8 Normalization Form C) are
67 // also illegal, but are not considered here.
IsNameServerIllegalAfterTrimming(const std::string & name)68 bool IsNameServerIllegalAfterTrimming(const std::string& name) {
69 size_t untrimmed_count = name.find_last_not_of(' ') + 1;
70 for (size_t i = 0; i < arraysize(kForbiddenServerNames); ++i) {
71 if (name.compare(0, untrimmed_count, kForbiddenServerNames[i]) == 0)
72 return true;
73 }
74 return false;
75 }
76
77 // Compare the values of two EntitySpecifics, accounting for encryption.
AreSpecificsEqual(const Cryptographer * cryptographer,const sync_pb::EntitySpecifics & left,const sync_pb::EntitySpecifics & right)78 bool AreSpecificsEqual(const Cryptographer* cryptographer,
79 const sync_pb::EntitySpecifics& left,
80 const sync_pb::EntitySpecifics& right) {
81 // Note that we can't compare encrypted strings directly as they are seeded
82 // with a random value.
83 std::string left_plaintext, right_plaintext;
84 if (left.has_encrypted()) {
85 if (!cryptographer->CanDecrypt(left.encrypted())) {
86 NOTREACHED() << "Attempting to compare undecryptable data.";
87 return false;
88 }
89 left_plaintext = cryptographer->DecryptToString(left.encrypted());
90 } else {
91 left_plaintext = left.SerializeAsString();
92 }
93 if (right.has_encrypted()) {
94 if (!cryptographer->CanDecrypt(right.encrypted())) {
95 NOTREACHED() << "Attempting to compare undecryptable data.";
96 return false;
97 }
98 right_plaintext = cryptographer->DecryptToString(right.encrypted());
99 } else {
100 right_plaintext = right.SerializeAsString();
101 }
102 if (left_plaintext == right_plaintext) {
103 return true;
104 }
105 return false;
106 }
107
AreAttachmentMetadataEqual(const sync_pb::AttachmentMetadata & left,const sync_pb::AttachmentMetadata & right)108 bool AreAttachmentMetadataEqual(const sync_pb::AttachmentMetadata& left,
109 const sync_pb::AttachmentMetadata& right) {
110 if (left.SerializeAsString() == right.SerializeAsString()) {
111 return true;
112 }
113 return false;
114 }
115
116 } // namespace syncer
117