lldb/source/Host/freebsd/Host.cpp

   1 //===-- source/Host/freebsd/Host.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 <sys/types.h>
  10
  11 #include <sys/exec.h>
  12 #include <sys/proc.h>
  13 #include <sys/ptrace.h>
  14 #include <sys/sysctl.h>
  15 #include <sys/user.h>
  16
  17 #include <machine/elf.h>
  18
  19 #include <cstdio>
  20 #include <dlfcn.h>
  21 #include <execinfo.h>
  22
  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/TargetParser/Host.h"
  35
  36 extern "C" {
  37 extern char **environ;
  38 }
  39
  40 namespace lldb_private {
  41 class ProcessLaunchInfo;
  42 }
  43
  44 using namespace lldb;
  45 using namespace lldb_private;
  46
  47 static bool
  48 GetFreeBSDProcessArgs(const ProcessInstanceInfoMatch *match_info_ptr,
  49                       ProcessInstanceInfo &process_info) {
  50   if (!process_info.ProcessIDIsValid())
  51     return false;
  52
  53   int pid = process_info.GetProcessID();
  54
  55   int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_ARGS, pid};
  56
  57   char arg_data[8192];
  58   size_t arg_data_size = sizeof(arg_data);
  59   if (::sysctl(mib, 4, arg_data, &arg_data_size, NULL, 0) != 0)
  60     return false;
  61
  62   DataExtractor data(arg_data, arg_data_size, endian::InlHostByteOrder(),
  63                      sizeof(void *));
  64   lldb::offset_t offset = 0;
  65   const char *cstr;
  66
  67   cstr = data.GetCStr(&offset);
  68   if (!cstr)
  69     return false;
  70
  71   // Get pathname for pid. If that fails fall back to argv[0].
  72   char pathname[MAXPATHLEN];
  73   size_t pathname_len = sizeof(pathname);
  74   mib[2] = KERN_PROC_PATHNAME;
  75   if (::sysctl(mib, 4, pathname, &pathname_len, NULL, 0) == 0)
  76     process_info.GetExecutableFile().SetFile(pathname, FileSpec::Style::native);
  77   else
  78     process_info.GetExecutableFile().SetFile(cstr, FileSpec::Style::native);
  79
  80   if (!(match_info_ptr == NULL ||
  81         NameMatches(process_info.GetExecutableFile().GetFilename().GetCString(),
  82                     match_info_ptr->GetNameMatchType(),
  83                     match_info_ptr->GetProcessInfo().GetName())))
  84     return false;
  85
  86   process_info.SetArg0(cstr);
  87   Args &proc_args = process_info.GetArguments();
  88   while (1) {
  89     const uint8_t *p = data.PeekData(offset, 1);
  90     while ((p != NULL) && (*p == '\0') && offset < arg_data_size) {
  91       ++offset;
  92       p = data.PeekData(offset, 1);
  93     }
  94     if (p == NULL || offset >= arg_data_size)
  95       break;
  96
  97     cstr = data.GetCStr(&offset);
  98     if (!cstr)
  99       break;
 100
 101     proc_args.AppendArgument(llvm::StringRef(cstr));
 102   }
 103
 104   return true;
 105 }
 106
 107 static bool GetFreeBSDProcessCPUType(ProcessInstanceInfo &process_info) {
 108   if (process_info.ProcessIDIsValid()) {
 109     process_info.GetArchitecture() =
 110         HostInfo::GetArchitecture(HostInfo::eArchKindDefault);
 111     return true;
 112   }
 113   process_info.GetArchitecture().Clear();
 114   return false;
 115 }
 116
 117 static bool GetFreeBSDProcessUserAndGroup(ProcessInstanceInfo &process_info) {
 118   struct kinfo_proc proc_kinfo;
 119   size_t proc_kinfo_size;
 120   const int pid = process_info.GetProcessID();
 121   int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PID, pid};
 122
 123   if (!process_info.ProcessIDIsValid())
 124     goto error;
 125
 126   proc_kinfo_size = sizeof(struct kinfo_proc);
 127
 128   if (::sysctl(mib, 4, &proc_kinfo, &proc_kinfo_size, NULL, 0) != 0)
 129     goto error;
 130
 131   if (proc_kinfo_size == 0)
 132     goto error;
 133
 134   process_info.SetParentProcessID(proc_kinfo.ki_ppid);
 135   process_info.SetUserID(proc_kinfo.ki_ruid);
 136   process_info.SetGroupID(proc_kinfo.ki_rgid);
 137   process_info.SetEffectiveUserID(proc_kinfo.ki_uid);
 138   if (proc_kinfo.ki_ngroups > 0)
 139     process_info.SetEffectiveGroupID(proc_kinfo.ki_groups[0]);
 140   else
 141     process_info.SetEffectiveGroupID(UINT32_MAX);
 142   return true;
 143
 144 error:
 145   process_info.SetParentProcessID(LLDB_INVALID_PROCESS_ID);
 146   process_info.SetUserID(UINT32_MAX);
 147   process_info.SetGroupID(UINT32_MAX);
 148   process_info.SetEffectiveUserID(UINT32_MAX);
 149   process_info.SetEffectiveGroupID(UINT32_MAX);
 150   return false;
 151 }
 152
 153 uint32_t Host::FindProcessesImpl(const ProcessInstanceInfoMatch &match_info,
 154                                  ProcessInstanceInfoList &process_infos) {
 155   const ::pid_t our_pid = ::getpid();
 156   const ::uid_t our_uid = ::getuid();
 157   std::vector<struct kinfo_proc> kinfos;
 158   // Special case, if lldb is being run as root we can attach to anything.
 159   bool all_users = match_info.GetMatchAllUsers() || (our_uid == 0);
 160
 161   int mib[3] = {CTL_KERN, KERN_PROC, KERN_PROC_ALL};
 162
 163   size_t pid_data_size = 0;
 164   if (::sysctl(mib, 3, NULL, &pid_data_size, NULL, 0) != 0)
 165     return 0;
 166
 167   // Add a few extra in case a few more show up
 168   const size_t estimated_pid_count =
 169       (pid_data_size / sizeof(struct kinfo_proc)) + 10;
 170
 171   kinfos.resize(estimated_pid_count);
 172   pid_data_size = kinfos.size() * sizeof(struct kinfo_proc);
 173
 174   if (::sysctl(mib, 3, &kinfos[0], &pid_data_size, NULL, 0) != 0)
 175     return 0;
 176
 177   const size_t actual_pid_count = (pid_data_size / sizeof(struct kinfo_proc));
 178
 179   ProcessInstanceInfoMatch match_info_noname{match_info};
 180   match_info_noname.SetNameMatchType(NameMatch::Ignore);
 181
 182   for (size_t i = 0; i < actual_pid_count; i++) {
 183     const struct kinfo_proc &kinfo = kinfos[i];
 184
 185     /* Make sure the user is acceptable */
 186     if (!all_users && kinfo.ki_ruid != our_uid)
 187       continue;
 188
 189     if (kinfo.ki_pid == our_pid ||  // Skip this process
 190         kinfo.ki_pid == 0 ||        // Skip kernel (kernel pid is 0)
 191         kinfo.ki_stat == SZOMB ||   // Zombies are bad
 192         kinfo.ki_flag & P_TRACED || // Being debugged?
 193         kinfo.ki_flag & P_WEXIT)    // Working on exiting
 194       continue;
 195
 196     // Every thread is a process in FreeBSD, but all the threads of a single
 197     // process have the same pid. Do not store the process info in the result
 198     // list if a process with given identifier is already registered there.
 199     bool already_registered = false;
 200     for (uint32_t pi = 0;
 201          !already_registered && (const int)kinfo.ki_numthreads > 1 &&
 202          pi < (const uint32_t)process_infos.size();
 203          pi++)
 204       already_registered =
 205           (process_infos[pi].GetProcessID() == (uint32_t)kinfo.ki_pid);
 206
 207     if (already_registered)
 208       continue;
 209
 210     ProcessInstanceInfo process_info;
 211     process_info.SetProcessID(kinfo.ki_pid);
 212     process_info.SetParentProcessID(kinfo.ki_ppid);
 213     process_info.SetUserID(kinfo.ki_ruid);
 214     process_info.SetGroupID(kinfo.ki_rgid);
 215     process_info.SetEffectiveUserID(kinfo.ki_svuid);
 216     process_info.SetEffectiveGroupID(kinfo.ki_svgid);
 217
 218     // Make sure our info matches before we go fetch the name and cpu type
 219     if (match_info_noname.Matches(process_info) &&
 220         GetFreeBSDProcessArgs(&match_info, process_info)) {
 221       GetFreeBSDProcessCPUType(process_info);
 222       if (match_info.Matches(process_info))
 223         process_infos.push_back(process_info);
 224     }
 225   }
 226
 227   return process_infos.size();
 228 }
 229
 230 bool Host::GetProcessInfo(lldb::pid_t pid, ProcessInstanceInfo &process_info) {
 231   process_info.SetProcessID(pid);
 232
 233   if (GetFreeBSDProcessArgs(NULL, process_info)) {
 234     // should use libprocstat instead of going right into sysctl?
 235     GetFreeBSDProcessCPUType(process_info);
 236     GetFreeBSDProcessUserAndGroup(process_info);
 237     return true;
 238   }
 239
 240   process_info.Clear();
 241   return false;
 242 }
 243
 244 Environment Host::GetEnvironment() { return Environment(environ); }
 245
 246 Status Host::ShellExpandArguments(ProcessLaunchInfo &launch_info) {
 247   return Status::FromErrorString("unimplemented");
 248 }