xref: /llvm-project/lldb/source/Host/netbsd/HostNetBSD.cpp (revision cb04bc05ebab5f44b13639c0e3613506180bdbac)
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 <cstdio>
10 #include <dlfcn.h>
11 #include <execinfo.h>
12 #include <sys/proc.h>
13 #include <sys/sysctl.h>
14 #include <sys/types.h>
15 
16 #include <climits>
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/LLDBLog.h"
29 #include "lldb/Utility/Log.h"
30 #include "lldb/Utility/NameMatches.h"
31 #include "lldb/Utility/ProcessInfo.h"
32 #include "lldb/Utility/Status.h"
33 #include "lldb/Utility/StreamString.h"
34 
35 #include "llvm/Object/ELF.h"
36 #include "llvm/TargetParser/Host.h"
37 
38 using namespace lldb;
39 using namespace lldb_private;
40 
41 namespace lldb_private {
42 class ProcessLaunchInfo;
43 }
44 
45 static bool GetNetBSDProcessArgs(const ProcessInstanceInfoMatch *match_info_ptr,
46                                  ProcessInstanceInfo &process_info) {
47   if (!process_info.ProcessIDIsValid())
48     return false;
49 
50   int pid = process_info.GetProcessID();
51 
52   int mib[4] = {CTL_KERN, KERN_PROC_ARGS, pid, KERN_PROC_ARGV};
53 
54   char arg_data[8192];
55   size_t arg_data_size = sizeof(arg_data);
56   if (::sysctl(mib, 4, arg_data, &arg_data_size, NULL, 0) != 0)
57     return false;
58 
59   DataExtractor data(arg_data, arg_data_size, endian::InlHostByteOrder(),
60                      sizeof(void *));
61   lldb::offset_t offset = 0;
62   const char *cstr;
63 
64   cstr = data.GetCStr(&offset);
65   if (!cstr)
66     return false;
67 
68   process_info.GetExecutableFile().SetFile(cstr,
69                                            FileSpec::Style::native);
70 
71   if (!(match_info_ptr == NULL ||
72         NameMatches(process_info.GetExecutableFile().GetFilename().GetCString(),
73                     match_info_ptr->GetNameMatchType(),
74                     match_info_ptr->GetProcessInfo().GetName())))
75     return false;
76 
77   process_info.SetArg0(cstr);
78   Args &proc_args = process_info.GetArguments();
79   while (1) {
80     const uint8_t *p = data.PeekData(offset, 1);
81     while ((p != NULL) && (*p == '\0') && offset < arg_data_size) {
82       ++offset;
83       p = data.PeekData(offset, 1);
84     }
85     if (p == NULL || offset >= arg_data_size)
86       break;
87 
88     cstr = data.GetCStr(&offset);
89     if (!cstr)
90       break;
91 
92     proc_args.AppendArgument(llvm::StringRef(cstr));
93   }
94 
95   return true;
96 }
97 
98 static bool GetNetBSDProcessCPUType(ProcessInstanceInfo &process_info) {
99   Log *log = GetLog(LLDBLog::Host);
100 
101   if (process_info.ProcessIDIsValid()) {
102     auto buffer_sp = FileSystem::Instance().CreateDataBuffer(
103         process_info.GetExecutableFile(), 0x20, 0);
104     if (buffer_sp) {
105       uint8_t exe_class =
106           llvm::object::getElfArchType(
107               {reinterpret_cast<const char *>(buffer_sp->GetBytes()),
108                size_t(buffer_sp->GetByteSize())})
109               .first;
110 
111       switch (exe_class) {
112       case llvm::ELF::ELFCLASS32:
113         process_info.GetArchitecture() =
114             HostInfo::GetArchitecture(HostInfo::eArchKind32);
115         return true;
116       case llvm::ELF::ELFCLASS64:
117         process_info.GetArchitecture() =
118             HostInfo::GetArchitecture(HostInfo::eArchKind64);
119         return true;
120       default:
121         LLDB_LOG(log, "Unknown elf class ({0}) in file {1}", exe_class,
122                  process_info.GetExecutableFile());
123       }
124     }
125   }
126   process_info.GetArchitecture().Clear();
127   return false;
128 }
129 
130 static bool GetNetBSDProcessUserAndGroup(ProcessInstanceInfo &process_info) {
131   ::kvm_t *kdp;
132   char errbuf[_POSIX2_LINE_MAX]; /* XXX: error string unused */
133 
134   struct ::kinfo_proc2 *proc_kinfo;
135   const int pid = process_info.GetProcessID();
136   int nproc;
137 
138   if (!process_info.ProcessIDIsValid())
139     goto error;
140 
141   if ((kdp = ::kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, errbuf)) == NULL)
142     goto error;
143 
144   if ((proc_kinfo = ::kvm_getproc2(kdp, KERN_PROC_PID, pid,
145                                    sizeof(struct ::kinfo_proc2), &nproc)) ==
146       NULL) {
147     ::kvm_close(kdp);
148     goto error;
149   }
150 
151   if (nproc < 1) {
152     ::kvm_close(kdp); /* XXX: we don't check for error here */
153     goto error;
154   }
155 
156   process_info.SetParentProcessID(proc_kinfo->p_ppid);
157   process_info.SetUserID(proc_kinfo->p_ruid);
158   process_info.SetGroupID(proc_kinfo->p_rgid);
159   process_info.SetEffectiveUserID(proc_kinfo->p_uid);
160   process_info.SetEffectiveGroupID(proc_kinfo->p_gid);
161 
162   ::kvm_close(kdp); /* XXX: we don't check for error here */
163 
164   return true;
165 
166 error:
167   process_info.SetParentProcessID(LLDB_INVALID_PROCESS_ID);
168   process_info.SetUserID(UINT32_MAX);
169   process_info.SetGroupID(UINT32_MAX);
170   process_info.SetEffectiveUserID(UINT32_MAX);
171   process_info.SetEffectiveGroupID(UINT32_MAX);
172   return false;
173 }
174 
175 uint32_t Host::FindProcessesImpl(const ProcessInstanceInfoMatch &match_info,
176                                  ProcessInstanceInfoList &process_infos) {
177   const ::pid_t our_pid = ::getpid();
178   const ::uid_t our_uid = ::getuid();
179 
180   const bool all_users =
181       match_info.GetMatchAllUsers() ||
182       // Special case, if lldb is being run as root we can attach to anything
183       (our_uid == 0);
184 
185   kvm_t *kdp;
186   char errbuf[_POSIX2_LINE_MAX]; /* XXX: error string unused */
187   if ((kdp = ::kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, errbuf)) == NULL)
188     return 0;
189 
190   struct ::kinfo_proc2 *proc_kinfo;
191   int nproc;
192   if ((proc_kinfo = ::kvm_getproc2(kdp, KERN_PROC_ALL, 0,
193                                    sizeof(struct ::kinfo_proc2), &nproc)) ==
194       NULL) {
195     ::kvm_close(kdp);
196     return 0;
197   }
198 
199   ProcessInstanceInfoMatch match_info_noname{match_info};
200   match_info_noname.SetNameMatchType(NameMatch::Ignore);
201 
202   for (int i = 0; i < nproc; i++) {
203     if (proc_kinfo[i].p_pid < 1)
204       continue; /* not valid */
205     /* Make sure the user is acceptable */
206     if (!all_users && proc_kinfo[i].p_ruid != our_uid)
207       continue;
208 
209     if (proc_kinfo[i].p_pid == our_pid ||  // Skip this process
210         proc_kinfo[i].p_pid == 0 ||        // Skip kernel (kernel pid is 0)
211         proc_kinfo[i].p_stat == LSZOMB ||  // Zombies are bad
212         proc_kinfo[i].p_flag & P_TRACED || // Being debugged?
213         proc_kinfo[i].p_flag & P_WEXIT)    // Working on exiting
214       continue;
215 
216     // Every thread is a process in NetBSD, but all the threads of a single
217     // process have the same pid. Do not store the process info in the result
218     // list if a process with given identifier is already registered there.
219     if (proc_kinfo[i].p_nlwps > 1) {
220       bool already_registered = false;
221       for (size_t pi = 0; pi < process_infos.size(); pi++) {
222         if ((::pid_t)process_infos[pi].GetProcessID() == proc_kinfo[i].p_pid) {
223           already_registered = true;
224           break;
225         }
226       }
227 
228       if (already_registered)
229         continue;
230     }
231     ProcessInstanceInfo process_info;
232     process_info.SetProcessID(proc_kinfo[i].p_pid);
233     process_info.SetParentProcessID(proc_kinfo[i].p_ppid);
234     process_info.SetUserID(proc_kinfo[i].p_ruid);
235     process_info.SetGroupID(proc_kinfo[i].p_rgid);
236     process_info.SetEffectiveUserID(proc_kinfo[i].p_uid);
237     process_info.SetEffectiveGroupID(proc_kinfo[i].p_gid);
238     // Make sure our info matches before we go fetch the name and cpu type
239     if (match_info_noname.Matches(process_info) &&
240         GetNetBSDProcessArgs(&match_info, process_info)) {
241       GetNetBSDProcessCPUType(process_info);
242       if (match_info.Matches(process_info))
243         process_infos.push_back(process_info);
244     }
245   }
246 
247   kvm_close(kdp); /* XXX: we don't check for error here */
248 
249   return process_infos.size();
250 }
251 
252 bool Host::GetProcessInfo(lldb::pid_t pid, ProcessInstanceInfo &process_info) {
253   process_info.SetProcessID(pid);
254 
255   if (GetNetBSDProcessArgs(NULL, process_info)) {
256     GetNetBSDProcessCPUType(process_info);
257     GetNetBSDProcessUserAndGroup(process_info);
258     return true;
259   }
260 
261   process_info.Clear();
262   return false;
263 }
264 
265 Status Host::ShellExpandArguments(ProcessLaunchInfo &launch_info) {
266   return Status::FromErrorString("unimplemented");
267 }
268