X-Git-Url: https://git.octo.it/?p=collectd.git;a=blobdiff_plain;f=src%2Fexec.c;h=f8707d4181269d82d4a87d1afb9b496ef0914a8f;hp=6be6faec7bcbefa78fb7123686c7498d38fd5167;hb=48efd3deb4c9139fd060ff3d289896e9031bcc7c;hpb=d544398864bc02dfd1623e6d005591b512e2f6c6

diff --git a/src/exec.c b/src/exec.c
index 6be6faec..f8707d41 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -26,13 +26,16 @@
 #define _DEFAULT_SOURCE
 #define _BSD_SOURCE /* For setgroups */
 
+/* _GNU_SOURCE is needed in Linux to use execvpe */
+#define _GNU_SOURCE
+
 #include "collectd.h"
 
-#include "common.h"
 #include "plugin.h"
+#include "utils/common/common.h"
 
-#include "utils_cmd_putnotif.h"
-#include "utils_cmd_putval.h"
+#include "utils/cmds/putnotif.h"
+#include "utils/cmds/putval.h"
 
 #include <grp.h>
 #include <pwd.h>
@@ -43,6 +46,8 @@
 #include <sys/capability.h>
 #endif
 
+extern char **environ;
+
 #define PL_NORMAL 0x01
 #define PL_NOTIF_ACTION 0x02
 
@@ -78,9 +83,14 @@ typedef struct program_list_and_notification_s {
 } program_list_and_notification_t;
 
 /*
+ * constants
+ */
+const long int MAX_GRBUF_SIZE = 65536;
+
+/*
  * Private variables
  */
-static program_list_t *pl_head = NULL;
+static program_list_t *pl_head;
 static pthread_mutex_t pl_lock = PTHREAD_MUTEX_INITIALIZER;
 
 /*
@@ -240,32 +250,11 @@ static int exec_config(oconfig_item_t *ci) /* {{{ */
   return 0;
 } /* int exec_config }}} */
 
-static void set_environment(void) /* {{{ */
-{
-  char buffer[1024];
-
-#ifdef HAVE_SETENV
-  snprintf(buffer, sizeof(buffer), "%.3f",
-           CDTIME_T_TO_DOUBLE(plugin_get_interval()));
-  setenv("COLLECTD_INTERVAL", buffer, /* overwrite = */ 1);
-
-  sstrncpy(buffer, hostname_g, sizeof(buffer));
-  setenv("COLLECTD_HOSTNAME", buffer, /* overwrite = */ 1);
-#else
-  snprintf(buffer, sizeof(buffer), "COLLECTD_INTERVAL=%.3f",
-           CDTIME_T_TO_DOUBLE(plugin_get_interval()));
-  putenv(buffer);
-
-  snprintf(buffer, sizeof(buffer), "COLLECTD_HOSTNAME=%s", hostname_g);
-  putenv(buffer);
-#endif
-} /* }}} void set_environment */
-
-__attribute__((noreturn)) static void exec_child(program_list_t *pl, int uid,
-                                                 int gid, int egid) /* {{{ */
+__attribute__((noreturn)) static void exec_child(program_list_t *pl,
+                                                 char **envp, int uid, int gid,
+                                                 int egid) /* {{{ */
 {
   int status;
-  char errbuf[1024];
 
 #if HAVE_SETGROUPS
   if (getuid() == 0) {
@@ -286,31 +275,32 @@ __attribute__((noreturn)) static void exec_child(program_list_t *pl, int uid,
 
   status = setgid(gid);
   if (status != 0) {
-    ERROR("exec plugin: setgid (%i) failed: %s", gid,
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("exec plugin: setgid (%i) failed: %s", gid, STRERRNO);
     exit(-1);
   }
 
   if (egid != -1) {
     status = setegid(egid);
     if (status != 0) {
-      ERROR("exec plugin: setegid (%i) failed: %s", egid,
-            sstrerror(errno, errbuf, sizeof(errbuf)));
+      ERROR("exec plugin: setegid (%i) failed: %s", egid, STRERRNO);
       exit(-1);
     }
   }
 
   status = setuid(uid);
   if (status != 0) {
-    ERROR("exec plugin: setuid (%i) failed: %s", uid,
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("exec plugin: setuid (%i) failed: %s", uid, STRERRNO);
     exit(-1);
   }
 
+#ifdef HAVE_EXECVPE
+  execvpe(pl->exec, pl->argv, envp);
+#else
+  environ = envp;
   execvp(pl->exec, pl->argv);
+#endif
 
-  ERROR("exec plugin: Failed to execute ``%s'': %s", pl->exec,
-        sstrerror(errno, errbuf, sizeof(errbuf)));
+  ERROR("exec plugin: Failed to execute ``%s'': %s", pl->exec, STRERRNO);
   exit(-1);
 } /* void exec_child }}} */
 
@@ -324,13 +314,11 @@ static void reset_signal_mask(void) /* {{{ */
 
 static int create_pipe(int fd_pipe[2]) /* {{{ */
 {
-  char errbuf[1024];
   int status;
 
   status = pipe(fd_pipe);
   if (status != 0) {
-    ERROR("exec plugin: pipe failed: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("exec plugin: pipe failed: %s", STRERRNO);
     return -1;
   }
 
@@ -347,6 +335,65 @@ static void close_pipe(int fd_pipe[2]) /* {{{ */
 } /* }}} void close_pipe */
 
 /*
+ * Get effective group ID from group name.
+ * Input arguments:
+ *       pl  :program list struct with group name
+ *       gid :group id to fallback in case egid cannot be determined.
+ * Returns:
+ *       egid effective group id if successfull,
+ *            -1 if group is not defined/not found.
+ *            -2 for any buffer allocation error.
+ */
+static int getegr_id(program_list_t *pl, int gid) /* {{{ */
+{
+  if (pl->group == NULL) {
+    return -1;
+  }
+  if (strcmp(pl->group, "") == 0) {
+    return gid;
+  }
+  struct group *gr_ptr = NULL;
+  struct group gr;
+
+  long int grbuf_size = sysconf(_SC_GETGR_R_SIZE_MAX);
+  if (grbuf_size <= 0)
+    grbuf_size = sysconf(_SC_PAGESIZE);
+  if (grbuf_size <= 0)
+    grbuf_size = 4096;
+
+  char *temp = NULL;
+  char *grbuf = NULL;
+
+  do {
+    temp = realloc(grbuf, grbuf_size);
+    if (temp == NULL) {
+      ERROR("exec plugin: getegr_id for %s: realloc buffer[%ld] failed ",
+            pl->group, grbuf_size);
+      sfree(grbuf);
+      return -2;
+    }
+    grbuf = temp;
+    if (getgrnam_r(pl->group, &gr, grbuf, grbuf_size, &gr_ptr) == 0) {
+      sfree(grbuf);
+      if (gr_ptr == NULL) {
+        ERROR("exec plugin: No such group: `%s'", pl->group);
+        return -1;
+      }
+      return gr.gr_gid;
+    } else if (errno == ERANGE) {
+      grbuf_size += grbuf_size; // increment buffer size and try again
+    } else {
+      ERROR("exec plugin: getegr_id failed %s", STRERRNO);
+      sfree(grbuf);
+      return -2;
+    }
+  } while (grbuf_size <= MAX_GRBUF_SIZE);
+  ERROR("exec plugin: getegr_id Max grbuf size reached  for %s", pl->group);
+  sfree(grbuf);
+  return -2;
+}
+
+/*
  * Creates three pipes (one for reading, one for writing and one for errors),
  * forks a child, sets up the pipes so that fd_in is connected to STDIN of
  * the child and fd_out is connected to STDOUT and fd_err is connected to STDERR
@@ -358,7 +405,6 @@ static int fork_child(program_list_t *pl, int *fd_in, int *fd_out,
   int fd_pipe_in[2] = {-1, -1};
   int fd_pipe_out[2] = {-1, -1};
   int fd_pipe_err[2] = {-1, -1};
-  char errbuf[1024];
   int status;
   int pid;
 
@@ -387,7 +433,7 @@ static int fork_child(program_list_t *pl, int *fd_in, int *fd_out,
   status = getpwnam_r(pl->user, &sp, nambuf, sizeof(nambuf), &sp_ptr);
   if (status != 0) {
     ERROR("exec plugin: Failed to get user information for user ``%s'': %s",
-          pl->user, sstrerror(status, errbuf, sizeof(errbuf)));
+          pl->user, STRERROR(status));
     goto failed;
   }
 
@@ -405,47 +451,47 @@ static int fork_child(program_list_t *pl, int *fd_in, int *fd_out,
 
   /* The group configured in the configfile is set as effective group, because
    * this way the forked process can (re-)gain the user's primary group. */
-  egid = -1;
-  if (pl->group != NULL) {
-    if (*pl->group != '\0') {
-      struct group *gr_ptr = NULL;
-      struct group gr;
-
-      long int grbuf_size = sysconf(_SC_GETGR_R_SIZE_MAX);
-      if (grbuf_size <= 0)
-        grbuf_size = sysconf(_SC_PAGESIZE);
-      if (grbuf_size <= 0)
-        grbuf_size = 4096;
-      char grbuf[grbuf_size];
-
-      status = getgrnam_r(pl->group, &gr, grbuf, sizeof(grbuf), &gr_ptr);
-      if (status != 0) {
-        ERROR("exec plugin: Failed to get group information "
-              "for group ``%s'': %s",
-              pl->group, sstrerror(status, errbuf, sizeof(errbuf)));
-        goto failed;
-      }
-      if (gr_ptr == NULL) {
-        ERROR("exec plugin: No such group: `%s'", pl->group);
-        goto failed;
-      }
+  egid = getegr_id(pl, gid);
+  if (egid == -2) {
+    goto failed;
+  }
 
-      egid = gr.gr_gid;
-    } else {
-      egid = gid;
-    }
-  } /* if (pl->group == NULL) */
+  double interval = CDTIME_T_TO_DOUBLE(plugin_get_interval());
 
   pid = fork();
   if (pid < 0) {
-    ERROR("exec plugin: fork failed: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("exec plugin: fork failed: %s", STRERRNO);
     goto failed;
   } else if (pid == 0) {
-    int fd_num;
+    char interval_buf[128];
+    snprintf(interval_buf, sizeof(interval_buf), "COLLECTD_INTERVAL=%.3f",
+             interval);
+
+    /* max hostname len is 255, so this should be enough */
+    char hostname_buf[300];
+    snprintf(hostname_buf, sizeof(hostname_buf), "COLLECTD_HOSTNAME=%s",
+             hostname_g);
+
+    size_t env_size = 0;
+    while (environ[env_size] != NULL) {
+      ++env_size;
+    }
+
+    /* Copy the environment variables */
+    char *envp[env_size + 3];
+    size_t envp_idx;
+    for (envp_idx = 0; environ[envp_idx] != NULL && envp_idx < env_size;
+         ++envp_idx) {
+      envp[envp_idx] = environ[envp_idx];
+    }
+
+    /* Add the collectd environment variables */
+    envp[envp_idx++] = interval_buf;
+    envp[envp_idx++] = hostname_buf;
+    envp[envp_idx++] = NULL;
 
     /* Close all file descriptors but the pipe end we need. */
-    fd_num = getdtablesize();
+    int fd_num = getdtablesize();
     for (int fd = 0; fd < fd_num; fd++) {
       if ((fd == fd_pipe_in[0]) || (fd == fd_pipe_out[1]) ||
           (fd == fd_pipe_err[1]))
@@ -471,12 +517,10 @@ static int fork_child(program_list_t *pl, int *fd_in, int *fd_out,
       close(fd_pipe_err[1]);
     }
 
-    set_environment();
-
     /* Unblock all signals */
     reset_signal_mask();
 
-    exec_child(pl, uid, gid, egid);
+    exec_child(pl, envp, uid, gid, egid);
     /* does not return */
   }
 
@@ -688,9 +732,7 @@ static void *exec_notification_one(void *arg) /* {{{ */
 
   fh = fdopen(fd, "w");
   if (fh == NULL) {
-    char errbuf[1024];
-    ERROR("exec plugin: fdopen (%i) failed: %s", fd,
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("exec plugin: fdopen (%i) failed: %s", fd, STRERRNO);
     kill(pid, SIGTERM);
     close(fd);
     sfree(arg);
@@ -703,8 +745,9 @@ static void *exec_notification_one(void *arg) /* {{{ */
   else if (n->severity == NOTIF_OKAY)
     severity = "OKAY";
 
-  fprintf(fh, "Severity: %s\n"
-              "Time: %.3f\n",
+  fprintf(fh,
+          "Severity: %s\n"
+          "Time: %.3f\n",
           severity, CDTIME_T_TO_DOUBLE(n->time));
 
   /* Print the optional fields */
@@ -867,6 +910,11 @@ static int exec_shutdown(void) /* {{{ */
       INFO("exec plugin: Sent SIGTERM to %hu", (unsigned short int)pl->pid);
     }
 
+    for (int i = 0; pl->argv[i] != NULL; i++) {
+      sfree(pl->argv[i]);
+    }
+    sfree(pl->argv);
+    sfree(pl->exec);
     sfree(pl->user);
     sfree(pl);