(#1096) Detect AppScope library state in the application

- check the state of application if was unscoped/scoped/loaded
- provide a dummy mapping for the loaded state

Closes #1096

cli/cmd/ps.go

@@ -38,6 +38,7 @@ var psCmd = &cobra.Command{
 			{Name: "Pid", Field: "pid"},
 			{Name: "User", Field: "user"},
 			{Name: "Command", Field: "command"},
+			{Name: "State", Field: "scoped"},
 		}, procs)
 	},
 }

cli/run/attach.go

@@ -74,8 +74,8 @@ func (rc *Config) Attach(args []string) error {
 		return errPidMissing
 	}
 	// Check PID is not already being scoped
-	if util.PidScoped(pid) {
-		return errAlreadyScope
+	if util.PidScopeState(pid) == util.Scoped {
+		util.ErrAndExit("Attach failed. This process is already being scoped")
 	}
 	// Create ldscope
 	if err := createLdscope(); err != nil {
@@ -115,7 +115,7 @@ func choosePid(procs util.Processes) (int, error) {
 		{Name: "ID", Field: "id"},
 		{Name: "Pid", Field: "pid"},
 		{Name: "User", Field: "user"},
-		{Name: "Scoped", Field: "scoped"},
+		{Name: "State", Field: "scoped"},
 		{Name: "Command", Field: "command"},
 	}, procs)
 	fmt.Println("Select an ID from the list:")

cli/run/start.go

@@ -139,7 +139,7 @@ func startAttach(allowProc allowProcConfig) error {
 	}
 
 	for pid, scopeState := range pidsToAttach {
-		if scopeState {
+		if scopeState == util.Scoped {
 			log.Info().
 				Str("pid", strconv.Itoa(pid)).
 				Msgf("Attach Failed. Process: %v is already scoped.", pid)

cli/util/proc.go

@@ -12,17 +12,30 @@ import (
 	linuxproc "github.com/c9s/goprocinfo/linux"
 )
 
+type ScopeState int
+
+const (
+	Unscoped ScopeState = iota
+	Scoped
+	Loaded
+	Unknown
+)
+
+func (ss ScopeState) String() string {
+	return []string{"Unscoped", "Scoped", "Loaded", "Unknown"}[ss]
+}
+
 // Process is a unix process
 type Process struct {
-	ID      int    `json:"id"`
-	Pid     int    `json:"pid"`
-	User    string `json:"user"`
-	Scoped  bool   `json:"scoped"`
-	Command string `json:"command"`
+	ID          int        `json:"id"`
+	Pid         int        `json:"pid"`
+	User        string     `json:"user"`
+	ScopeStatus ScopeState `json:"scoped"`
+	Command     string     `json:"command"`
 }
 
 // PidScopeMap is a map of Pid and Scope state
-type PidScopeMapState map[int]bool
+type PidScopeMapState map[int]ScopeState
 
 // Processes is an array of Process
 type Processes []Process
@@ -85,7 +98,7 @@ func pidScopeMapSearch(inputArg string, sF searchFun) (PidScopeMapState, error)
 		}
 
 		if sF(pid, inputArg) {
-			pidMap[pid] = PidScoped(pid)
+			pidMap[pid] = PidScopeState(pid)
 		}
 	}
 
@@ -149,11 +162,11 @@ func ProcessesByName(name string) (Processes, error) {
 		// Add process if there is a name match
 		if strings.Contains(command, name) {
 			processes = append(processes, Process{
-				ID:      i,
-				Pid:     pid,
-				User:    userName,
-				Scoped:  PidScoped(pid),
-				Command: cmdLine,
+				ID:          i,
+				Pid:         pid,
+				User:        userName,
+				ScopeStatus: PidScopeState(pid),
+				Command:     cmdLine,
 			})
 			i++
 		}
@@ -200,15 +213,15 @@ func ProcessesScoped() (Processes, error) {
 			continue
 		}
 
-		// Add process if is is scoped
-		scoped := PidScoped(pid)
-		if scoped {
+		// Add process if is is scoped or loaded
+		scopeState := PidScopeState(pid)
+		if scopeState == Scoped || scopeState == Loaded {
 			processes = append(processes, Process{
-				ID:      i,
-				Pid:     pid,
-				User:    userName,
-				Scoped:  scoped,
-				Command: cmdLine,
+				ID:          i,
+				Pid:         pid,
+				User:        userName,
+				ScopeStatus: scopeState,
+				Command:     cmdLine,
 			})
 			i++
 		}
@@ -234,24 +247,31 @@ func PidUser(pid int) (string, error) {
 	return user.Username, nil
 }
 
-// PidScoped checks if a process specified by PID is being scoped
-func PidScoped(pid int) bool {
+// PidScopeState retrieve Scope state of a process specified by PID
+func PidScopeState(pid int) ScopeState {
 	pidMapFile, err := ioutil.ReadFile(fmt.Sprintf("/proc/%v/maps", pid))
 	if err != nil {
-		return false
+		return Unknown
 	}
 
 	// Look for libscope in map
 	pidMap := string(pidMapFile)
 	if strings.Contains(pidMap, "libscope") {
 		command, err := PidCommand(pid)
 		if err != nil {
-			return false
+			return Unknown
+		}
+
+		if command == "ldscopedyn" {
+			return Unscoped
 		}
-		return command != "ldscopedyn"
+		if strings.Contains(pidMap, "scope_loaded") {
+			return Loaded
+		}
+		return Scoped
 	}
 
-	return false
+	return Unscoped
 }
 
 // PidCommand gets the command used to start the process specified by PID

cli/util/proc_test.go

@@ -20,11 +20,11 @@ func TestProcessesByName(t *testing.T) {
 	user, _ := user.Current()
 	exp := Processes{
 		Process{
-			ID:      1,
-			Pid:     os.Getpid(),
-			User:    user.Username,
-			Command: strings.Join(os.Args[:], " "),
-			Scoped:  false,
+			ID:          1,
+			Pid:         os.Getpid(),
+			User:        user.Username,
+			Command:     strings.Join(os.Args[:], " "),
+			ScopeStatus: Unscoped,
 		},
 	}
 	assert.Equal(t, exp, result)
@@ -42,7 +42,7 @@ func TestPidScopeMapByProcessName(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Len(t, pidMap, 1)
 	assert.Contains(t, pidMap, os.Getpid())
-	assert.Equal(t, pidMap[os.Getpid()], false)
+	assert.Equal(t, pidMap[os.Getpid()], Unscoped)
 }
 
 // TestPidScopeMapByProcessName
@@ -70,7 +70,7 @@ func TestPidScopeMapByCmdLine(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Len(t, pidMap, 1)
 	assert.Contains(t, pidMap, os.Getpid())
-	assert.Equal(t, pidMap[os.Getpid()], false)
+	assert.Equal(t, pidMap[os.Getpid()], Unscoped)
 }
 
 // TestPidScopeMapByCmdLineCharShorter
@@ -86,7 +86,7 @@ func TestPidScopeMapByCmdLineCharShorter(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Len(t, pidMap, 1)
 	assert.Contains(t, pidMap, os.Getpid())
-	assert.Equal(t, pidMap[os.Getpid()], false)
+	assert.Equal(t, pidMap[os.Getpid()], Unscoped)
 }
 
 // TestPidUser

os/linux/Makefile

@@ -106,6 +106,7 @@ coretest: $(C_FILES) $(YAML_AR) $(JSON_AR) $(TEST_LIB)
 	$(CC) $(TEST_CFLAGS) -o test/$(OS)/httpstatetest httpstatetest.o httpstate.o plattime.o search.o fn.o utils.o os.o scopestdlib.o dbg.o test.o com.o cfg.o cfgutils.o mtc.o mtcformat.o strset.o ctl.o transport.o linklist.o log.o evtformat.o circbuf.o state.o metriccapture.o report.o httpagg.o $(TEST_AR) $(TEST_LD_FLAGS) -Wl,--wrap=cmdPostEvent -lrt
 	$(CC) $(TEST_CFLAGS) -o test/$(OS)/httpheadertest httpheadertest.o report.o httpagg.o state.o com.o httpstate.o metriccapture.o plattime.o fn.o utils.o os.o ctl.o log.o transport.o scopestdlib.o dbg.o cfgutils.o cfg.o mtc.o evtformat.o mtcformat.o strset.o circbuf.o linklist.o search.o test.o $(TEST_AR) $(TEST_LD_FLAGS) -Wl,--wrap=cmdSendHttp -Wl,--wrap=cmdPostEvent
 	$(CC) $(TEST_CFLAGS) -o test/$(OS)/httpaggtest httpaggtest.o httpagg.o fn.o utils.o scopestdlib.o dbg.o plattime.o os.o test.o $(TEST_AR) $(TEST_LD_FLAGS)
+	$(CC) $(TEST_CFLAGS) -o test/$(OS)/libstatetest libstatetest.o libstate.o scopestdlib.o dbg.o test.o $(TEST_AR) $(TEST_LD_FLAGS)
 	$(CC) $(TEST_CFLAGS) -o test/$(OS)/reporttest reporttest.o report.o httpagg.o state.o httpstate.o metriccapture.o com.o plattime.o fn.o utils.o os.o ctl.o log.o transport.o scopestdlib.o dbg.o cfgutils.o cfg.o mtc.o evtformat.o mtcformat.o strset.o circbuf.o linklist.o search.o test.o $(TEST_AR) $(TEST_LD_FLAGS) -Wl,--wrap=cmdSendEvent -Wl,--wrap=cmdSendMetric
 	$(CC) $(TEST_CFLAGS) -o test/$(OS)/mtcformattest mtcformattest.o mtcformat.o strset.o scopestdlib.o dbg.o log.o transport.o com.o ctl.o mtc.o evtformat.o cfg.o cfgutils.o linklist.o fn.o utils.o circbuf.o os.o test.o report.o search.o httpagg.o state.o httpstate.o metriccapture.o plattime.o $(TEST_AR) $(TEST_LD_FLAGS)
 	$(CC) $(TEST_CFLAGS) -o test/$(OS)/circbuftest circbuftest.o circbuf.o scopestdlib.o dbg.o test.o $(TEST_AR) $(TEST_LD_FLAGS)

os/linux/aarch64.mk

@@ -5,7 +5,7 @@ ARCH_OBJ=$(ARCH)
 LD_FLAGS=$(MUSL_AR) $(UNWIND_AR) $(PCRE2_AR) $(LS_HPACK_AR) $(YAML_AR) $(JSON_AR) -ldl -lpthread -lrt -lresolv -Lcontrib/build/funchook -lfunchook -Lcontrib/build/funchook/capstone_src-prefix/src/capstone_src-build -lcapstone
 INCLUDES=-I./contrib/libyaml/include -I./contrib/cJSON -I./os/$(OS) -I./contrib/pcre2/src -I./contrib/build/pcre2 -I./contrib/funchook/capstone_src/include/ -I./contrib/jni -I./contrib/jni/linux/ -I./contrib/openssl/include -I./contrib/build/openssl/include -I./contrib/build/libunwind/include  -I./contrib/libunwind/include/
 
-$(LIBSCOPE): src/wrap.c src/state.c src/httpstate.c src/metriccapture.c src/report.c src/httpagg.c src/plattime.c src/fn.c os/$(OS)/os.c src/cfgutils.c src/cfg.c src/transport.c src/log.c src/mtc.c src/circbuf.c src/linklist.c src/evtformat.c src/ctl.c src/mtcformat.c src/com.c src/scopestdlib.c src/dbg.c src/search.c src/scopeelf.c src/utils.c src/strset.c src/javabci.c src/javaagent.c
+$(LIBSCOPE): src/wrap.c src/state.c src/httpstate.c src/metriccapture.c src/report.c src/httpagg.c src/plattime.c src/fn.c os/$(OS)/os.c src/cfgutils.c src/libstate.c src/cfg.c src/transport.c src/log.c src/mtc.c src/circbuf.c src/linklist.c src/evtformat.c src/ctl.c src/mtcformat.c src/com.c src/scopestdlib.c src/dbg.c src/search.c src/scopeelf.c src/utils.c src/strset.c src/javabci.c src/javaagent.c
 	@$(MAKE) -C contrib funchook pcre2 openssl ls-hpack musl libyaml libunwind cJSON
 	@echo "$${CI:+::group::}Building $@"
 	$(CC) $(CFLAGS) \

os/linux/x86_64.mk

@@ -11,7 +11,7 @@ INCLUDES=-I./contrib/libyaml/include -I./contrib/cJSON -I./os/$(OS) -I./contrib/
 #	objcopy -I binary -O elf64-x86-64 -B i386 ./lib/$(OS)/libscope.so ./lib/$(OS)/libscope.o && \
 #	rm -f ./lib/$(OS)/libscope.so
 
-$(LIBSCOPE): src/wrap.c src/state.c src/httpstate.c src/metriccapture.c src/report.c src/httpagg.c src/plattime.c src/fn.c os/$(OS)/os.c src/cfgutils.c src/cfg.c src/transport.c src/log.c src/mtc.c src/circbuf.c src/linklist.c src/evtformat.c src/ctl.c src/mtcformat.c src/com.c src/scopestdlib.c src/dbg.c src/search.c src/sysexec.c src/gocontext.S src/scopeelf.c src/wrap_go.c src/utils.c src/strset.c src/javabci.c src/javaagent.c
+$(LIBSCOPE): src/wrap.c src/state.c src/httpstate.c src/metriccapture.c src/report.c src/httpagg.c src/plattime.c src/fn.c os/$(OS)/os.c src/cfgutils.c src/libstate.c src/cfg.c src/transport.c src/log.c src/mtc.c src/circbuf.c src/linklist.c src/evtformat.c src/ctl.c src/mtcformat.c src/com.c src/scopestdlib.c src/dbg.c src/search.c src/sysexec.c src/gocontext.S src/scopeelf.c src/wrap_go.c src/utils.c src/strset.c src/javabci.c src/javaagent.c
 	@$(MAKE) -C contrib funchook pcre2 openssl ls-hpack musl libyaml cJSON libunwind
 	@echo "$${CI:+::group::}Building $@"
 	$(CC) $(CFLAGS) $(ARCH_CFLAGS) \

src/libstate.c

@@ -0,0 +1,82 @@
+#include "libstate.h"
+#include <fcntl.h>
+#include "scopestdlib.h"
+
+static void *loadedStrMap = NULL;
+#define LOADED_MAP_SIZE (4096)
+
+/*
+ * AppScope state describes the process state in context of the AppScope library.
+ * We recognize two states:
+ * - Scoped - when all the functions are funchooked
+ * - AppScope library is loaded - when execve family functions are funchooked
+ * 
+ * The distinguish between the AppScope states is based on presence of the "loaded mapping".
+ * 
+ * Example loaded mapping view in /proc/<PID>/maps:
+ * 7fa2b4734000-7fa2b4735000 rw-s 00000000 103:07 23856559  /tmp/scope_loaded.2142471 (deleted)
+ */
+
+/*
+ * libstateLoaded sets the loaded state for the current process by:
+ * - creating a temporary file `/tmp/scope_loaded.<pid>`. 
+ * - the file is mapped into the process memory as "loaded mapping"
+ * - the file is removed (unlinked)
+ */
+bool
+libstateLoaded(pid_t pid) {
+    char path[PATH_MAX] = {0};
+    bool res = FALSE;
+    /*
+    * Switching to "loaded" AppScope state:
+    * We are done if mapping is present.
+    */
+    if (loadedStrMap) {
+        return TRUE;
+    }
+
+    if (scope_snprintf(path, sizeof(path), "/tmp/scope_loaded.%d", pid) < 0) {
+        return res;
+    }
+
+    int outFd = scope_open(path, O_RDWR | O_CREAT, 0664);
+    if (outFd == -1)  {
+        return res;
+    }
+
+    if (scope_ftruncate(outFd, LOADED_MAP_SIZE) != 0) {
+        goto close_file;
+    }
+
+    void* dest = scope_mmap(NULL, LOADED_MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, outFd, 0);
+    if (dest == MAP_FAILED) {
+        goto close_file;
+    }
+
+    loadedStrMap = dest;
+
+    res = TRUE;
+
+close_file:
+    scope_close(outFd);
+    if (scope_unlink(path) != 0 ) {
+        return FALSE;
+    }
+    return res;
+}
+
+/*
+ * libstateScoped sets the scoped state for the current process by unmap the "loaded mapping"
+ */
+bool
+libstateScoped(void) {
+    /*
+    * Switching to "scoped" AppScope state:
+    * We remove "loaded mapping" if present.
+    */
+    if (loadedStrMap != NULL ) {
+        scope_munmap(loadedStrMap, LOADED_MAP_SIZE);
+        loadedStrMap = NULL;
+    }
+    return TRUE;
+}

src/libstate.h

@@ -0,0 +1,10 @@
+
+#ifndef __LIBSTATE_H__
+#define __LIBSTATE_H__
+
+#include "scopetypes.h"
+
+bool libstateLoaded(pid_t);
+bool libstateScoped(void);
+
+#endif // __LIBSTATE_H__

src/runtimecfg.h

@@ -4,7 +4,7 @@
 #include "cfg.h"
 
 typedef struct rtconfig_t {
-    bool funcs_attached;       // TRUE when functions are interposed, FALSE otherwise
+    bool funcs_scoped;       // TRUE when all the functions are interposed, FALSE if only exec* are
     int blockconn;
     config_t *staticfg;
 } rtconfig;