1 // Copyright 2010 Google LLC
2 //
3 // Redistribution and use in source and binary forms, with or without
4 // modification, are permitted provided that the following conditions are
5 // met:
6 //
7 // * Redistributions of source code must retain the above copyright
8 // notice, this list of conditions and the following disclaimer.
9 // * Redistributions in binary form must reproduce the above
10 // copyright notice, this list of conditions and the following disclaimer
11 // in the documentation and/or other materials provided with the
12 // distribution.
13 // * Neither the name of Google LLC nor the names of its
14 // contributors may be used to endorse or promote products derived from
15 // this software without specific prior written permission.
16 //
17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
29 #ifdef HAVE_CONFIG_H
30 #include <config.h> // Must come first
31 #endif
32
33 #include "client/linux/crash_generation/crash_generation_client.h"
34
35 #include <stdio.h>
36 #include <sys/socket.h>
37 #include <sys/types.h>
38
39 #include <algorithm>
40
41 #include "common/linux/eintr_wrapper.h"
42 #include "common/linux/ignore_ret.h"
43 #include "third_party/lss/linux_syscall_support.h"
44
45 namespace google_breakpad {
46
47 namespace {
48
49 class CrashGenerationClientImpl : public CrashGenerationClient {
50 public:
CrashGenerationClientImpl(int server_fd)51 explicit CrashGenerationClientImpl(int server_fd) : server_fd_(server_fd) {}
52 CrashGenerationClientImpl(const CrashGenerationClientImpl&) = delete;
53 void operator=(const CrashGenerationClientImpl&) = delete;
54 ~CrashGenerationClientImpl() override = default;
55
RequestDump(const void * blob,size_t blob_size)56 bool RequestDump(const void* blob, size_t blob_size) override {
57 int fds[2];
58 if (sys_pipe(fds) < 0)
59 return false;
60 static const unsigned kControlMsgSize = CMSG_SPACE(sizeof(int));
61
62 struct kernel_iovec iov;
63 iov.iov_base = const_cast<void*>(blob);
64 iov.iov_len = blob_size;
65
66 struct kernel_msghdr msg = { 0 };
67 msg.msg_iov = &iov;
68 msg.msg_iovlen = 1;
69 char cmsg[kControlMsgSize] = "";
70 msg.msg_control = cmsg;
71 msg.msg_controllen = sizeof(cmsg);
72
73 struct cmsghdr* hdr = CMSG_FIRSTHDR(&msg);
74 hdr->cmsg_level = SOL_SOCKET;
75 hdr->cmsg_type = SCM_RIGHTS;
76 hdr->cmsg_len = CMSG_LEN(sizeof(int));
77 int* p = reinterpret_cast<int*>(CMSG_DATA(hdr));
78 *p = fds[1];
79
80 ssize_t ret = HANDLE_EINTR(sys_sendmsg(server_fd_, &msg, 0));
81 sys_close(fds[1]);
82 if (ret < 0) {
83 sys_close(fds[0]);
84 return false;
85 }
86
87 // Wait for an ACK from the server.
88 char b;
89 IGNORE_RET(HANDLE_EINTR(sys_read(fds[0], &b, 1)));
90 sys_close(fds[0]);
91
92 return true;
93 }
94
95 private:
96 int server_fd_;
97 };
98
99 } // namespace
100
101 // static
TryCreate(int server_fd)102 CrashGenerationClient* CrashGenerationClient::TryCreate(int server_fd) {
103 if (server_fd < 0)
104 return NULL;
105 return new CrashGenerationClientImpl(server_fd);
106 }
107
108 } // namespace google_breakpad
109