1 /*
2  *
3  * Copyright 2016 gRPC authors.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  */
18 #include <grpc/support/port_platform.h>
19 
20 #include "src/core/lib/iomgr/port.h"
21 
22 #ifdef GRPC_HAVE_UNIX_SOCKET
23 
24 #include "src/core/lib/iomgr/sockaddr.h"
25 
26 #include <string.h>
27 #include <sys/stat.h>
28 #include <sys/types.h>
29 #include <sys/un.h>
30 
31 #include "src/core/lib/iomgr/unix_sockets_posix.h"
32 
33 #include <grpc/support/alloc.h>
34 #include <grpc/support/log.h>
35 
36 #include "src/core/lib/gpr/useful.h"
37 
grpc_create_socketpair_if_unix(int sv[2])38 void grpc_create_socketpair_if_unix(int sv[2]) {
39   GPR_ASSERT(socketpair(AF_UNIX, SOCK_STREAM, 0, sv) == 0);
40 }
41 
grpc_resolve_unix_domain_address(const char * name,grpc_resolved_addresses ** addrs)42 grpc_error* grpc_resolve_unix_domain_address(const char* name,
43                                              grpc_resolved_addresses** addrs) {
44   struct sockaddr_un* un;
45   if (strlen(name) >
46       GPR_ARRAY_SIZE(((struct sockaddr_un*)nullptr)->sun_path) - 1) {
47     char* err_msg;
48     grpc_error* err;
49     gpr_asprintf(&err_msg,
50                  "Path name should not have more than %" PRIuPTR " characters.",
51                  GPR_ARRAY_SIZE(un->sun_path) - 1);
52     err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(err_msg);
53     gpr_free(err_msg);
54     return err;
55   }
56   *addrs = static_cast<grpc_resolved_addresses*>(
57       gpr_malloc(sizeof(grpc_resolved_addresses)));
58   (*addrs)->naddrs = 1;
59   (*addrs)->addrs = static_cast<grpc_resolved_address*>(
60       gpr_malloc(sizeof(grpc_resolved_address)));
61   un = reinterpret_cast<struct sockaddr_un*>((*addrs)->addrs->addr);
62   un->sun_family = AF_UNIX;
63   strncpy(un->sun_path, name, sizeof(un->sun_path));
64   (*addrs)->addrs->len =
65       static_cast<socklen_t>(strlen(un->sun_path) + sizeof(un->sun_family) + 1);
66   return GRPC_ERROR_NONE;
67 }
68 
grpc_is_unix_socket(const grpc_resolved_address * resolved_addr)69 int grpc_is_unix_socket(const grpc_resolved_address* resolved_addr) {
70   const grpc_sockaddr* addr =
71       reinterpret_cast<const grpc_sockaddr*>(resolved_addr->addr);
72   return addr->sa_family == AF_UNIX;
73 }
74 
grpc_unlink_if_unix_domain_socket(const grpc_resolved_address * resolved_addr)75 void grpc_unlink_if_unix_domain_socket(
76     const grpc_resolved_address* resolved_addr) {
77   const grpc_sockaddr* addr =
78       reinterpret_cast<const grpc_sockaddr*>(resolved_addr->addr);
79   if (addr->sa_family != AF_UNIX) {
80     return;
81   }
82   struct sockaddr_un* un = reinterpret_cast<struct sockaddr_un*>(
83       const_cast<char*>(resolved_addr->addr));
84   struct stat st;
85 
86   if (stat(un->sun_path, &st) == 0 && (st.st_mode & S_IFMT) == S_IFSOCK) {
87     unlink(un->sun_path);
88   }
89 }
90 
grpc_sockaddr_to_uri_unix_if_possible(const grpc_resolved_address * resolved_addr)91 char* grpc_sockaddr_to_uri_unix_if_possible(
92     const grpc_resolved_address* resolved_addr) {
93   const grpc_sockaddr* addr =
94       reinterpret_cast<const grpc_sockaddr*>(resolved_addr->addr);
95   if (addr->sa_family != AF_UNIX) {
96     return nullptr;
97   }
98 
99   char* result;
100   gpr_asprintf(&result, "unix:%s", ((struct sockaddr_un*)addr)->sun_path);
101   return result;
102 }
103 
104 #endif
105