start_stop_daemon: add -chuid support

5 files changed, 70 insertions, 42 deletions

diff --git a/coreutils/chown.c b/coreutils/chown.c
index dad5ce063..3380677bc 100644
--- a/coreutils/chown.c
+++ b/coreutils/chown.c
@@ -56,7 +56,6 @@ static int fileAction(const char *fileName, struct stat *statbuf,
 int chown_main(int argc, char **argv);
 int chown_main(int argc, char **argv)
 {
-        char *groupName;
         int retval = EXIT_SUCCESS;
 
         opt_complementary = "-2";
@@ -65,24 +64,7 @@ int chown_main(int argc, char **argv)
 
         if (OPT_NODEREF) chown_func = lchown;
 
-        /* First, check if there is a group name here */
-        groupName = strchr(*argv, '.'); /* deprecated? */
-        if (!groupName)
-                groupName = strchr(*argv, ':');
-        else
-                *groupName = ':'; /* replace '.' with ':' */
-
-        /* First, try parsing "user[:[group]]" */
-        if (!groupName) { /* "user" */
-                ugid.uid = get_ug_id(*argv, xuname2uid);
-        } else if (groupName == *argv) { /* ":group" */
-                ugid.gid = get_ug_id(groupName + 1, xgroup2gid);
-        } else {
-                if (!groupName[1]) /* "user:" */
-                        *groupName = '\0';
-                if (!get_uidgid(&ugid, *argv, 1))
-                        bb_error_msg_and_die("unknown user/group %s", *argv);
-        }
+        parse_chown_usergroup_or_die(&ugid, argv[0]);
 
         /* Ok, ready to do the deed now */
         argv++;
diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c
index eb2427a50..1862f113d 100644
--- a/debianutils/start_stop_daemon.c
+++ b/debianutils/start_stop_daemon.c
@@ -14,12 +14,11 @@
 
 static int signal_nr = 15;
 static int user_id = -1;
-static int quiet;
 static char *userspec;
-static char *chuid;
 static char *cmdname;
 static char *execname;
 static char *pidfile;
+static smallint quiet;
 
 struct pid_list {
         struct pid_list *next;
@@ -222,20 +221,28 @@ static const struct option long_options[] = {
 enum {
         CTX_STOP       = 0x1,
         CTX_START      = 0x2,
-        OPT_BACKGROUND = 0x4,
-        OPT_QUIET      = 0x8,
-        OPT_MAKEPID    = 0x10,
-        OPT_OKNODO     = 0x20 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY,
-        OPT_VERBOSE    = 0x40 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY,
-        OPT_NICELEVEL  = 0x80 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY,
+        OPT_BACKGROUND = 0x4, // -b
+        OPT_QUIET      = 0x8, // -q
+        OPT_MAKEPID    = 0x10, // -m
+        OPT_a          = 0x20, // -a
+        OPT_n          = 0x40, // -n
+        OPT_s          = 0x80, // -s
+        OPT_u          = 0x100, // -u
+        OPT_c          = 0x200, // -c
+        OPT_x          = 0x400, // -x
+        OPT_p          = 0x800, // -p
+        OPT_OKNODO     = 0x1000 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -o
+        OPT_VERBOSE    = 0x2000 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -v
+        OPT_NICELEVEL  = 0x4000 * ENABLE_FEATURE_START_STOP_DAEMON_FANCY, // -N
 };
 
 int start_stop_daemon_main(int argc, char **argv);
 int start_stop_daemon_main(int argc, char **argv)
 {
         unsigned opt;
-        char *signame = NULL;
-        char *startas = NULL;
+        char *signame;
+        char *startas;
+        char *chuid;
 #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
 //      char *retry_arg = NULL;
 //      int retries = -1;
@@ -247,22 +254,22 @@ int start_stop_daemon_main(int argc, char **argv)
 
         /* Check required one context option was given */
         opt_complementary = "K:S:?:K--S:S--K:m?p:K?xpun:S?xa";
-        opt = getopt32(argc, argv, "KSbqm"
-//              USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:R:")
-                USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:")
-                "a:n:s:u:c:x:p:"
+        opt = getopt32(argc, argv, "KSbqma:n:s:u:c:x:p:"
+                USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:"),
+//              USE_FEATURE_START_STOP_DAEMON_FANCY("ovN:R:"),
+                &startas, &cmdname, &signame, &userspec, &chuid, &execname, &pidfile
                 USE_FEATURE_START_STOP_DAEMON_FANCY(,&opt_N)
 //              USE_FEATURE_START_STOP_DAEMON_FANCY(,&retry_arg)
-                ,&startas, &cmdname, &signame, &userspec, &chuid, &execname, &pidfile);
+        );
 
         quiet = (opt & OPT_QUIET) && !(opt & OPT_VERBOSE);
 
-        if (signame) {
+        if (opt & OPT_s) {
                 signal_nr = get_signum(signame);
                 if (signal_nr < 0) bb_show_usage();
         }
 
-        if (!startas)
+        if (!(opt & OPT_a))
                 startas = execname;
 
 //      USE_FEATURE_START_STOP_DAEMON_FANCY(
@@ -303,11 +310,11 @@ int start_stop_daemon_main(int argc, char **argv)
                 fprintf(pidf, "%d\n", pidt);
                 fclose(pidf);
         }
-        if (chuid) {
-                user_id = bb_strtou(chuid, NULL, 10);
-                if (errno)
-                        user_id = xuname2uid(chuid);
-                xsetuid(user_id);
+        if (opt & OPT_c) {
+                struct bb_uidgid_t ugid;
+                parse_chown_usergroup_or_die(&ugid, chuid);
+                if (ugid.gid != (gid_t) -1) xsetgid(ugid.gid);
+                if (ugid.uid != (uid_t) -1) xsetuid(ugid.uid);
         }
 #if ENABLE_FEATURE_START_STOP_DAEMON_FANCY
         if (opt & OPT_NICELEVEL) {
diff --git a/include/libbb.h b/include/libbb.h
index a32e6154c..4293ae269 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -443,7 +443,10 @@ struct bb_uidgid_t {
         uid_t uid;
         gid_t gid;
 };
+/* always sets uid and gid */
 int get_uidgid(struct bb_uidgid_t*, const char*, int numeric_ok);
+/* chown-like handling of "user[:[group]" */
+void parse_chown_usergroup_or_die(struct bb_uidgid_t *u, char *user_group);
 /* what is this? */
 /*extern char *bb_getug(char *buffer, char *idname, long id, int bufsize, char prefix);*/
 char *bb_getpwuid(char *name, long uid, int bufsize);
diff --git a/include/usage.h b/include/usage.h
index 52f972038..04dddd7c3 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -2893,7 +2893,7 @@
        "\n      -N|--nicelevel <N>              Add N to process's nice level" \
         ) \
        "\n      -s|--signal <signal>            Signal to send (default TERM)" \
-       "\n      -U|--chuid <username>|<uid>     Start process with this name"
+       "\n      -c|--chuid <user>[:[<group>]]   Change to specified user/group"
 
 #define stat_trivial_usage \
        "[OPTION] FILE..."
diff --git a/libpwdgrp/uidgid_get.c b/libpwdgrp/uidgid_get.c
index 69c228e16..f10b40654 100644
--- a/libpwdgrp/uidgid_get.c
+++ b/libpwdgrp/uidgid_get.c
@@ -27,6 +27,7 @@ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "busybox.h"
 
+/* Always sets uid and gid */
 int get_uidgid(struct bb_uidgid_t *u, const char *ug, int numeric_ok)
 {
         struct passwd *pwd;
@@ -53,6 +54,7 @@ int get_uidgid(struct bb_uidgid_t *u, const char *ug, int numeric_ok)
                         goto skip;
                 }
         }
+        /* Either it is not numeric, or caller disallows numeric username */
         pwd = getpwnam(user);
         if (!pwd)
                 return 0;
@@ -75,6 +77,40 @@ int get_uidgid(struct bb_uidgid_t *u, const char *ug, int numeric_ok)
         return 1;
 }
 
+/* chown-like:
+ * "user" sets uid only,
+ * ":group" sets gid only
+ * "user:" sets uid and gid (to user's primary group id)
+ * "user:group" sets uid and gid
+ * ('unset' uid or gid is actually set to -1)
+ */
+void parse_chown_usergroup_or_die(struct bb_uidgid_t *u, char *user_group)
+{
+        char *group;
+
+        u->uid = -1;
+        u->gid = -1;
+
+        /* Check if there is a group name */
+        group = strchr(user_group, '.'); /* deprecated? */
+        if (!group)
+                group = strchr(user_group, ':');
+        else
+                *group = ':'; /* replace '.' with ':' */
+
+        /* Parse "user[:[group]]" */
+        if (!group) { /* "user" */
+                u->uid = get_ug_id(user_group, xuname2uid);
+        } else if (group == user_group) { /* ":group" */
+                u->gid = get_ug_id(group + 1, xgroup2gid);
+        } else {
+                if (!group[1]) /* "user:" */
+                        *group = '\0';
+                if (!get_uidgid(u, user_group, 1))
+                        bb_error_msg_and_die("unknown user/group %s", user_group);
+        }
+}
+
 #if 0
 #include <stdio.h>
 int main()