1 //===-- DomainSocket.cpp --------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "lldb/Host/posix/DomainSocket.h"
10
11 #include "llvm/Support/Errno.h"
12 #include "llvm/Support/FileSystem.h"
13
14 #include <cstddef>
15 #include <sys/socket.h>
16 #include <sys/un.h>
17
18 using namespace lldb;
19 using namespace lldb_private;
20
21 #ifdef __ANDROID__
22 // Android does not have SUN_LEN
23 #ifndef SUN_LEN
24 #define SUN_LEN(ptr) \
25 (offsetof(struct sockaddr_un, sun_path) + strlen((ptr)->sun_path))
26 #endif
27 #endif // #ifdef __ANDROID__
28
29 static const int kDomain = AF_UNIX;
30 static const int kType = SOCK_STREAM;
31
SetSockAddr(llvm::StringRef name,const size_t name_offset,sockaddr_un * saddr_un,socklen_t & saddr_un_len)32 static bool SetSockAddr(llvm::StringRef name, const size_t name_offset,
33 sockaddr_un *saddr_un, socklen_t &saddr_un_len) {
34 if (name.size() + name_offset > sizeof(saddr_un->sun_path))
35 return false;
36
37 memset(saddr_un, 0, sizeof(*saddr_un));
38 saddr_un->sun_family = kDomain;
39
40 memcpy(saddr_un->sun_path + name_offset, name.data(), name.size());
41
42 // For domain sockets we can use SUN_LEN in order to calculate size of
43 // sockaddr_un, but for abstract sockets we have to calculate size manually
44 // because of leading null symbol.
45 if (name_offset == 0)
46 saddr_un_len = SUN_LEN(saddr_un);
47 else
48 saddr_un_len =
49 offsetof(struct sockaddr_un, sun_path) + name_offset + name.size();
50
51 #if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
52 saddr_un->sun_len = saddr_un_len;
53 #endif
54
55 return true;
56 }
57
DomainSocket(bool should_close,bool child_processes_inherit)58 DomainSocket::DomainSocket(bool should_close, bool child_processes_inherit)
59 : Socket(ProtocolUnixDomain, should_close, child_processes_inherit) {}
60
DomainSocket(SocketProtocol protocol,bool child_processes_inherit)61 DomainSocket::DomainSocket(SocketProtocol protocol,
62 bool child_processes_inherit)
63 : Socket(protocol, true, child_processes_inherit) {}
64
DomainSocket(NativeSocket socket,const DomainSocket & listen_socket)65 DomainSocket::DomainSocket(NativeSocket socket,
66 const DomainSocket &listen_socket)
67 : Socket(ProtocolUnixDomain, listen_socket.m_should_close_fd,
68 listen_socket.m_child_processes_inherit) {
69 m_socket = socket;
70 }
71
Connect(llvm::StringRef name)72 Status DomainSocket::Connect(llvm::StringRef name) {
73 sockaddr_un saddr_un;
74 socklen_t saddr_un_len;
75 if (!SetSockAddr(name, GetNameOffset(), &saddr_un, saddr_un_len))
76 return Status("Failed to set socket address");
77
78 Status error;
79 m_socket = CreateSocket(kDomain, kType, 0, m_child_processes_inherit, error);
80 if (error.Fail())
81 return error;
82 if (llvm::sys::RetryAfterSignal(-1, ::connect, GetNativeSocket(),
83 (struct sockaddr *)&saddr_un, saddr_un_len) < 0)
84 SetLastError(error);
85
86 return error;
87 }
88
Listen(llvm::StringRef name,int backlog)89 Status DomainSocket::Listen(llvm::StringRef name, int backlog) {
90 sockaddr_un saddr_un;
91 socklen_t saddr_un_len;
92 if (!SetSockAddr(name, GetNameOffset(), &saddr_un, saddr_un_len))
93 return Status("Failed to set socket address");
94
95 DeleteSocketFile(name);
96
97 Status error;
98 m_socket = CreateSocket(kDomain, kType, 0, m_child_processes_inherit, error);
99 if (error.Fail())
100 return error;
101 if (::bind(GetNativeSocket(), (struct sockaddr *)&saddr_un, saddr_un_len) ==
102 0)
103 if (::listen(GetNativeSocket(), backlog) == 0)
104 return error;
105
106 SetLastError(error);
107 return error;
108 }
109
Accept(Socket * & socket)110 Status DomainSocket::Accept(Socket *&socket) {
111 Status error;
112 auto conn_fd = AcceptSocket(GetNativeSocket(), nullptr, nullptr,
113 m_child_processes_inherit, error);
114 if (error.Success())
115 socket = new DomainSocket(conn_fd, *this);
116
117 return error;
118 }
119
GetNameOffset() const120 size_t DomainSocket::GetNameOffset() const { return 0; }
121
DeleteSocketFile(llvm::StringRef name)122 void DomainSocket::DeleteSocketFile(llvm::StringRef name) {
123 llvm::sys::fs::remove(name);
124 }
125
GetSocketName() const126 std::string DomainSocket::GetSocketName() const {
127 if (m_socket == kInvalidSocketValue)
128 return "";
129
130 struct sockaddr_un saddr_un;
131 saddr_un.sun_family = AF_UNIX;
132 socklen_t sock_addr_len = sizeof(struct sockaddr_un);
133 if (::getpeername(m_socket, (struct sockaddr *)&saddr_un, &sock_addr_len) !=
134 0)
135 return "";
136
137 if (sock_addr_len <= offsetof(struct sockaddr_un, sun_path))
138 return ""; // Unnamed domain socket
139
140 llvm::StringRef name(saddr_un.sun_path + GetNameOffset(),
141 sock_addr_len - offsetof(struct sockaddr_un, sun_path) -
142 GetNameOffset());
143 name = name.rtrim('\0');
144
145 return name.str();
146 }
147
GetRemoteConnectionURI() const148 std::string DomainSocket::GetRemoteConnectionURI() const {
149 std::string name = GetSocketName();
150 if (name.empty())
151 return name;
152
153 return llvm::formatv(
154 "{0}://{1}",
155 GetNameOffset() == 0 ? "unix-connect" : "unix-abstract-connect", name);
156 }
157