1 //===-- source/Host/netbsd/HostNetBSD.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 <dlfcn.h>
10 #include <execinfo.h>
11 #include <stdio.h>
12 #include <sys/proc.h>
13 #include <sys/sysctl.h>
14 #include <sys/types.h>
15 
16 #include <limits.h>
17 
18 #include <kvm.h>
19 #include <sys/exec.h>
20 #include <sys/ptrace.h>
21 
22 #include "lldb/Host/FileSystem.h"
23 #include "lldb/Host/Host.h"
24 #include "lldb/Host/HostInfo.h"
25 #include "lldb/Utility/DataBufferHeap.h"
26 #include "lldb/Utility/DataExtractor.h"
27 #include "lldb/Utility/Endian.h"
28 #include "lldb/Utility/Log.h"
29 #include "lldb/Utility/NameMatches.h"
30 #include "lldb/Utility/ProcessInfo.h"
31 #include "lldb/Utility/Status.h"
32 #include "lldb/Utility/StreamString.h"
33 
34 #include "llvm/Object/ELF.h"
35 #include "llvm/Support/Host.h"
36 
37 extern "C" {
38 extern char **environ;
39 }
40 
41 using namespace lldb;
42 using namespace lldb_private;
43 
44 namespace lldb_private {
45 class ProcessLaunchInfo;
46 }
47 
48 Environment Host::GetEnvironment() { return Environment(environ); }
49 
50 static bool GetNetBSDProcessArgs(const ProcessInstanceInfoMatch *match_info_ptr,
51                                  ProcessInstanceInfo &process_info) {
52   if (!process_info.ProcessIDIsValid())
53     return false;
54 
55   int pid = process_info.GetProcessID();
56 
57   int mib[4] = {CTL_KERN, KERN_PROC_ARGS, pid, KERN_PROC_ARGV};
58 
59   char arg_data[8192];
60   size_t arg_data_size = sizeof(arg_data);
61   if (::sysctl(mib, 4, arg_data, &arg_data_size, NULL, 0) != 0)
62     return false;
63 
64   DataExtractor data(arg_data, arg_data_size, endian::InlHostByteOrder(),
65                      sizeof(void *));
66   lldb::offset_t offset = 0;
67   const char *cstr;
68 
69   cstr = data.GetCStr(&offset);
70   if (!cstr)
71     return false;
72 
73   process_info.GetExecutableFile().SetFile(cstr,
74                                            FileSpec::Style::native);
75 
76   if (!(match_info_ptr == NULL ||
77         NameMatches(process_info.GetExecutableFile().GetFilename().GetCString(),
78                     match_info_ptr->GetNameMatchType(),
79                     match_info_ptr->GetProcessInfo().GetName())))
80     return false;
81 
82   process_info.SetArg0(cstr);
83   Args &proc_args = process_info.GetArguments();
84   while (1) {
85     const uint8_t *p = data.PeekData(offset, 1);
86     while ((p != NULL) && (*p == '\0') && offset < arg_data_size) {
87       ++offset;
88       p = data.PeekData(offset, 1);
89     }
90     if (p == NULL || offset >= arg_data_size)
91       break;
92 
93     cstr = data.GetCStr(&offset);
94     if (!cstr)
95       break;
96 
97     proc_args.AppendArgument(llvm::StringRef(cstr));
98   }
99 
100   return true;
101 }
102 
103 static bool GetNetBSDProcessCPUType(ProcessInstanceInfo &process_info) {
104   Log *log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST);
105 
106   if (process_info.ProcessIDIsValid()) {
107     auto buffer_sp = FileSystem::Instance().CreateDataBuffer(
108         process_info.GetExecutableFile(), 0x20, 0);
109     if (buffer_sp) {
110       uint8_t exe_class =
111           llvm::object::getElfArchType(
112               {buffer_sp->GetChars(), size_t(buffer_sp->GetByteSize())})
113               .first;
114 
115       switch (exe_class) {
116       case llvm::ELF::ELFCLASS32:
117         process_info.GetArchitecture() =
118             HostInfo::GetArchitecture(HostInfo::eArchKind32);
119         return true;
120       case llvm::ELF::ELFCLASS64:
121         process_info.GetArchitecture() =
122             HostInfo::GetArchitecture(HostInfo::eArchKind64);
123         return true;
124       default:
125         LLDB_LOG(log, "Unknown elf class ({0}) in file {1}", exe_class,
126                  process_info.GetExecutableFile());
127       }
128     }
129   }
130   process_info.GetArchitecture().Clear();
131   return false;
132 }
133 
134 static bool GetNetBSDProcessUserAndGroup(ProcessInstanceInfo &process_info) {
135   ::kvm_t *kdp;
136   char errbuf[_POSIX2_LINE_MAX]; /* XXX: error string unused */
137 
138   struct ::kinfo_proc2 *proc_kinfo;
139   const int pid = process_info.GetProcessID();
140   int nproc;
141 
142   if (!process_info.ProcessIDIsValid())
143     goto error;
144 
145   if ((kdp = ::kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, errbuf)) == NULL)
146     goto error;
147 
148   if ((proc_kinfo = ::kvm_getproc2(kdp, KERN_PROC_PID, pid,
149                                    sizeof(struct ::kinfo_proc2), &nproc)) ==
150       NULL) {
151     ::kvm_close(kdp);
152     goto error;
153   }
154 
155   if (nproc < 1) {
156     ::kvm_close(kdp); /* XXX: we don't check for error here */
157     goto error;
158   }
159 
160   process_info.SetParentProcessID(proc_kinfo->p_ppid);
161   process_info.SetUserID(proc_kinfo->p_ruid);
162   process_info.SetGroupID(proc_kinfo->p_rgid);
163   process_info.SetEffectiveUserID(proc_kinfo->p_uid);
164   process_info.SetEffectiveGroupID(proc_kinfo->p_gid);
165 
166   ::kvm_close(kdp); /* XXX: we don't check for error here */
167 
168   return true;
169 
170 error:
171   process_info.SetParentProcessID(LLDB_INVALID_PROCESS_ID);
172   process_info.SetUserID(UINT32_MAX);
173   process_info.SetGroupID(UINT32_MAX);
174   process_info.SetEffectiveUserID(UINT32_MAX);
175   process_info.SetEffectiveGroupID(UINT32_MAX);
176   return false;
177 }
178 
179 uint32_t Host::FindProcessesImpl(const ProcessInstanceInfoMatch &match_info,
180                                  ProcessInstanceInfoList &process_infos) {
181   const ::pid_t our_pid = ::getpid();
182   const ::uid_t our_uid = ::getuid();
183 
184   const bool all_users =
185       match_info.GetMatchAllUsers() ||
186       // Special case, if lldb is being run as root we can attach to anything
187       (our_uid == 0);
188 
189   kvm_t *kdp;
190   char errbuf[_POSIX2_LINE_MAX]; /* XXX: error string unused */
191   if ((kdp = ::kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, errbuf)) == NULL)
192     return 0;
193 
194   struct ::kinfo_proc2 *proc_kinfo;
195   int nproc;
196   if ((proc_kinfo = ::kvm_getproc2(kdp, KERN_PROC_ALL, 0,
197                                    sizeof(struct ::kinfo_proc2), &nproc)) ==
198       NULL) {
199     ::kvm_close(kdp);
200     return 0;
201   }
202 
203   for (int i = 0; i < nproc; i++) {
204     if (proc_kinfo[i].p_pid < 1)
205       continue; /* not valid */
206     /* Make sure the user is acceptable */
207     if (!all_users && proc_kinfo[i].p_ruid != our_uid)
208       continue;
209 
210     if (proc_kinfo[i].p_pid == our_pid ||  // Skip this process
211         proc_kinfo[i].p_pid == 0 ||        // Skip kernel (kernel pid is 0)
212         proc_kinfo[i].p_stat == LSZOMB ||  // Zombies are bad
213         proc_kinfo[i].p_flag & P_TRACED || // Being debugged?
214         proc_kinfo[i].p_flag & P_WEXIT)    // Working on exiting
215       continue;
216 
217     // Every thread is a process in NetBSD, but all the threads of a single
218     // process have the same pid. Do not store the process info in the result
219     // list if a process with given identifier is already registered there.
220     if (proc_kinfo[i].p_nlwps > 1) {
221       bool already_registered = false;
222       for (size_t pi = 0; pi < process_infos.size(); pi++) {
223         if (process_infos[pi].GetProcessID() == proc_kinfo[i].p_pid) {
224           already_registered = true;
225           break;
226         }
227       }
228 
229       if (already_registered)
230         continue;
231     }
232     ProcessInstanceInfo process_info;
233     process_info.SetProcessID(proc_kinfo[i].p_pid);
234     process_info.SetParentProcessID(proc_kinfo[i].p_ppid);
235     process_info.SetUserID(proc_kinfo[i].p_ruid);
236     process_info.SetGroupID(proc_kinfo[i].p_rgid);
237     process_info.SetEffectiveUserID(proc_kinfo[i].p_uid);
238     process_info.SetEffectiveGroupID(proc_kinfo[i].p_gid);
239     // Make sure our info matches before we go fetch the name and cpu type
240     if (match_info.Matches(process_info) &&
241         GetNetBSDProcessArgs(&match_info, process_info)) {
242       GetNetBSDProcessCPUType(process_info);
243       if (match_info.Matches(process_info))
244         process_infos.push_back(process_info);
245     }
246   }
247 
248   kvm_close(kdp); /* XXX: we don't check for error here */
249 
250   return process_infos.size();
251 }
252 
253 bool Host::GetProcessInfo(lldb::pid_t pid, ProcessInstanceInfo &process_info) {
254   process_info.SetProcessID(pid);
255 
256   if (GetNetBSDProcessArgs(NULL, process_info)) {
257     GetNetBSDProcessCPUType(process_info);
258     GetNetBSDProcessUserAndGroup(process_info);
259     return true;
260   }
261 
262   process_info.Clear();
263   return false;
264 }
265 
266 Status Host::ShellExpandArguments(ProcessLaunchInfo &launch_info) {
267   return Status("unimplemented");
268 }
269