X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=execute.c;h=7192abfffb8cc7776735841920dbcfe132cdc111;hp=bf9a087c050d354ace8477fb6dfb8989e8ec0ccb;hb=25e870b5f79f158ba6ac0b715248b0c3d3549325;hpb=02a51abad1d6f334599c8d648b18d000b6118eb5

diff --git a/execute.c b/execute.c
index bf9a087c0..7192abfff 100644
--- a/execute.c
+++ b/execute.c
@@ -34,6 +34,8 @@
 #include <sys/stat.h>
 #include <grp.h>
 #include <pwd.h>
+#include <sys/mount.h>
+#include <linux/fs.h>
 
 #include "execute.h"
 #include "strv.h"
@@ -43,6 +45,7 @@
 #include "ioprio.h"
 #include "securebits.h"
 #include "cgroup.h"
+#include "namespace.h"
 
 /* This assumes there is a 'tty' group */
 #define TTY_MODE 0620
@@ -73,7 +76,7 @@ static int shift_fds(int fds[], unsigned n_fds) {
                         if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
                                 return -errno;
 
-                        assert_se(close_nointr(fds[i]) == 0);
+                        close_nointr_nofail(fds[i]);
                         fds[i] = nfd;
 
                         /* Hmm, the fd we wanted isn't free? Then
@@ -91,7 +94,7 @@ static int shift_fds(int fds[], unsigned n_fds) {
         return 0;
 }
 
-static int flags_fds(int fds[], unsigned n_fds, bool nonblock) {
+static int flags_fds(const int fds[], unsigned n_fds, bool nonblock) {
         unsigned i;
         int r;
 
@@ -137,7 +140,7 @@ static int open_null_as(int flags, int nfd) {
 
         if (fd != nfd) {
                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
-                close_nointr(fd);
+                close_nointr_nofail(fd);
         } else
                 r = nfd;
 
@@ -191,7 +194,7 @@ static int connect_logger_as(const ExecContext *context, ExecOutput output, cons
 
         if (fd != nfd) {
                 r = dup2(fd, nfd) < 0 ? -errno : nfd;
-                close_nointr(fd);
+                close_nointr_nofail(fd);
         } else
                 r = nfd;
 
@@ -222,10 +225,41 @@ static bool is_terminal_input(ExecInput i) {
                 i == EXEC_INPUT_TTY_FAIL;
 }
 
-static int setup_input(const ExecContext *context) {
+static int fixup_input(const ExecContext *context, int socket_fd) {
+        assert(context);
+
+        if (socket_fd < 0 && context->std_input == EXEC_INPUT_SOCKET)
+                return EXEC_INPUT_NULL;
+
+        return context->std_input;
+}
+
+static int fixup_output(const ExecContext *context, int socket_fd) {
+        assert(context);
+
+        if (socket_fd < 0 && context->std_output == EXEC_OUTPUT_SOCKET)
+                return EXEC_OUTPUT_INHERIT;
+
+        return context->std_output;
+}
+
+static int fixup_error(const ExecContext *context, int socket_fd) {
+        assert(context);
+
+        if (socket_fd < 0 && context->std_error == EXEC_OUTPUT_SOCKET)
+                return EXEC_OUTPUT_INHERIT;
+
+        return context->std_error;
+}
+
+static int setup_input(const ExecContext *context, int socket_fd) {
+        ExecInput i;
+
         assert(context);
 
-        switch (context->std_input) {
+        i = fixup_input(context, socket_fd);
+
+        switch (i) {
 
         case EXEC_INPUT_NULL:
                 return open_null_as(O_RDONLY, STDIN_FILENO);
@@ -237,8 +271,8 @@ static int setup_input(const ExecContext *context) {
 
                 if ((fd = acquire_terminal(
                                      tty_path(context),
-                                     context->std_input == EXEC_INPUT_TTY_FAIL,
-                                     context->std_input == EXEC_INPUT_TTY_FORCE)) < 0)
+                                     i == EXEC_INPUT_TTY_FAIL,
+                                     i == EXEC_INPUT_TTY_FORCE)) < 0)
                         return fd;
 
                 if (fd != STDIN_FILENO) {
@@ -250,72 +284,90 @@ static int setup_input(const ExecContext *context) {
                 return r;
         }
 
+        case EXEC_INPUT_SOCKET:
+                return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
+
         default:
                 assert_not_reached("Unknown input type");
         }
 }
 
-static int setup_output(const ExecContext *context, const char *ident) {
+static int setup_output(const ExecContext *context, int socket_fd, const char *ident) {
+        ExecOutput o;
+        ExecInput i;
+
         assert(context);
         assert(ident);
 
+        i = fixup_input(context, socket_fd);
+        o = fixup_output(context, socket_fd);
+
         /* This expects the input is already set up */
 
-        switch (context->std_output) {
+        switch (o) {
 
         case EXEC_OUTPUT_INHERIT:
 
                 /* If the input is connected to a terminal, inherit that... */
-                if (is_terminal_input(context->std_input))
+                if (is_terminal_input(i) || i == EXEC_INPUT_SOCKET)
                         return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 
-                return 0;
+                return STDIN_FILENO;
 
         case EXEC_OUTPUT_NULL:
                 return open_null_as(O_WRONLY, STDOUT_FILENO);
 
-        case EXEC_OUTPUT_TTY: {
-                if (is_terminal_input(context->std_input))
+        case EXEC_OUTPUT_TTY:
+                if (is_terminal_input(i))
                         return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 
                 /* We don't reset the terminal if this is just about output */
                 return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
-        }
 
         case EXEC_OUTPUT_SYSLOG:
         case EXEC_OUTPUT_KERNEL:
-                return connect_logger_as(context, context->std_output, ident, STDOUT_FILENO);
+                return connect_logger_as(context, o, ident, STDOUT_FILENO);
+
+        case EXEC_OUTPUT_SOCKET:
+                assert(socket_fd >= 0);
+                return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
 
         default:
                 assert_not_reached("Unknown output type");
         }
 }
 
-static int setup_error(const ExecContext *context, const char *ident) {
+static int setup_error(const ExecContext *context, int socket_fd, const char *ident) {
+        ExecOutput o, e;
+        ExecInput i;
+
         assert(context);
         assert(ident);
 
+        i = fixup_input(context, socket_fd);
+        o = fixup_output(context, socket_fd);
+        e = fixup_error(context, socket_fd);
+
         /* This expects the input and output are already set up */
 
         /* Don't change the stderr file descriptor if we inherit all
          * the way and are not on a tty */
-        if (context->std_error == EXEC_OUTPUT_INHERIT &&
-            context->std_output == EXEC_OUTPUT_INHERIT &&
-            !is_terminal_input(context->std_input))
+        if (e == EXEC_OUTPUT_INHERIT &&
+            o == EXEC_OUTPUT_INHERIT &&
+            !is_terminal_input(i))
                 return STDERR_FILENO;
 
         /* Duplicate form stdout if possible */
-        if (context->std_error == context->std_output ||
-            context->std_error == EXEC_OUTPUT_INHERIT)
+        if (e == o || e == EXEC_OUTPUT_INHERIT)
                 return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 
-        switch (context->std_error) {
+        switch (e) {
 
         case EXEC_OUTPUT_NULL:
                 return open_null_as(O_WRONLY, STDERR_FILENO);
 
         case EXEC_OUTPUT_TTY:
-                if (is_terminal_input(context->std_input))
+                if (is_terminal_input(i))
                         return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 
                 /* We don't reset the terminal if this is just about output */
@@ -323,7 +375,11 @@ static int setup_error(const ExecContext *context, const char *ident) {
 
         case EXEC_OUTPUT_SYSLOG:
         case EXEC_OUTPUT_KERNEL:
-                return connect_logger_as(context, context->std_error, ident, STDERR_FILENO);
+                return connect_logger_as(context, e, ident, STDERR_FILENO);
+
+        case EXEC_OUTPUT_SOCKET:
+                assert(socket_fd >= 0);
+                return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
 
         default:
                 assert_not_reached("Unknown error type");
@@ -334,7 +390,6 @@ static int chown_terminal(int fd, uid_t uid) {
         struct stat st;
 
         assert(fd >= 0);
-        assert(uid >= 0);
 
         /* This might fail. What matters are the results. */
         fchown(fd, uid, -1);
@@ -343,8 +398,7 @@ static int chown_terminal(int fd, uid_t uid) {
         if (fstat(fd, &st) < 0)
                 return -errno;
 
-        if (st.st_uid != uid ||
-            st.st_mode != TTY_MODE)
+        if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
                 return -EPERM;
 
         return 0;
@@ -414,7 +468,7 @@ fail:
         return r;
 }
 
-static int restore_conform_stdio(const ExecContext *context,
+static int restore_confirm_stdio(const ExecContext *context,
                                  int *saved_stdin,
                                  int *saved_stdout,
                                  bool *keep_stdin,
@@ -667,8 +721,9 @@ static int enforce_user(const ExecContext *context, uid_t uid) {
 }
 
 int exec_spawn(ExecCommand *command,
+               char **argv,
                const ExecContext *context,
-               int *fds, unsigned n_fds,
+               int fds[], unsigned n_fds,
                bool apply_permissions,
                bool apply_chroot,
                bool confirm_spawn,
@@ -678,13 +733,31 @@ int exec_spawn(ExecCommand *command,
         pid_t pid;
         int r;
         char *line;
+        int socket_fd;
 
         assert(command);
         assert(context);
         assert(ret);
         assert(fds || n_fds <= 0);
 
-        if (!(line = exec_command_line(command)))
+        if (context->std_input == EXEC_INPUT_SOCKET ||
+            context->std_output == EXEC_OUTPUT_SOCKET ||
+            context->std_error == EXEC_OUTPUT_SOCKET) {
+
+                if (n_fds != 1)
+                        return -EINVAL;
+
+                socket_fd = fds[0];
+
+                fds = NULL;
+                n_fds = 0;
+        } else
+                socket_fd = -1;
+
+        if (!argv)
+                argv = command->argv;
+
+        if (!(line = exec_command_line(argv)))
                 return -ENOMEM;
 
         log_debug("About to execute: %s", line);
@@ -718,12 +791,11 @@ int exec_spawn(ExecCommand *command,
                         goto fail;
                 }
 
-                if (setsid() < 0) {
-                        r = EXIT_SETSID;
-                        goto fail;
-                }
-
-                umask(context->umask);
+                if (!context->no_setsid)
+                        if (setsid() < 0) {
+                                r = EXIT_SETSID;
+                                goto fail;
+                        }
 
                 if (confirm_spawn) {
                         char response;
@@ -734,7 +806,7 @@ int exec_spawn(ExecCommand *command,
                                 goto fail;
 
                         /* Now ask the question. */
-                        if (!(line = exec_command_line(command))) {
+                        if (!(line = exec_command_line(argv))) {
                                 r = EXIT_MEMORY;
                                 goto fail;
                         }
@@ -751,25 +823,25 @@ int exec_spawn(ExecCommand *command,
                         }
 
                         /* Release terminal for the question */
-                        if ((r = restore_conform_stdio(context,
+                        if ((r = restore_confirm_stdio(context,
                                                        &saved_stdin, &saved_stdout,
                                                        &keep_stdin, &keep_stdout)))
                                 goto fail;
                 }
 
                 if (!keep_stdin)
-                        if (setup_input(context) < 0) {
+                        if (setup_input(context, socket_fd) < 0) {
                                 r = EXIT_STDIN;
                                 goto fail;
                         }
 
                 if (!keep_stdout)
-                        if (setup_output(context, file_name_from_path(command->path)) < 0) {
+                        if (setup_output(context, socket_fd, file_name_from_path(command->path)) < 0) {
                                 r = EXIT_STDOUT;
                                 goto fail;
                         }
 
-                if (setup_error(context, file_name_from_path(command->path)) < 0) {
+                if (setup_error(context, socket_fd, file_name_from_path(command->path)) < 0) {
                         r = EXIT_STDERR;
                         goto fail;
                 }
@@ -829,12 +901,31 @@ int exec_spawn(ExecCommand *command,
                                 goto fail;
                         }
 
+                if (strv_length(context->read_write_dirs) > 0 ||
+                    strv_length(context->read_only_dirs) > 0 ||
+                    strv_length(context->inaccessible_dirs) > 0 ||
+                    context->mount_flags != MS_SHARED ||
+                    context->private_tmp)
+                        if ((r = setup_namespace(
+                                             context->read_write_dirs,
+                                             context->read_only_dirs,
+                                             context->inaccessible_dirs,
+                                             context->private_tmp,
+                                             context->mount_flags)) < 0)
+                                goto fail;
+
                 if (context->user) {
                         username = context->user;
                         if (get_user_creds(&username, &uid, &gid, &home) < 0) {
                                 r = EXIT_USER;
                                 goto fail;
                         }
+
+                        if (is_terminal_input(context->std_input))
+                                if (chown_terminal(STDIN_FILENO, uid) < 0) {
+                                        r = EXIT_STDIN;
+                                        goto fail;
+                                }
                 }
 
                 if (apply_permissions)
@@ -843,11 +934,7 @@ int exec_spawn(ExecCommand *command,
                                 goto fail;
                         }
 
-                if (is_terminal_input(context->std_input))
-                        if (chown_terminal(STDIN_FILENO, uid) < 0) {
-                                r = EXIT_STDIN;
-                                goto fail;
-                        }
+                umask(context->umask);
 
                 if (apply_chroot) {
                         if (context->root_directory)
@@ -952,7 +1039,7 @@ int exec_spawn(ExecCommand *command,
                         goto fail;
                 }
 
-                execve(command->path, command->argv, final_env);
+                execve(command->path, argv, final_env);
                 r = EXIT_EXEC;
 
         fail:
@@ -992,30 +1079,10 @@ void exec_context_init(ExecContext *c) {
         assert(c);
 
         c->umask = 0002;
-        c->oom_adjust = 0;
-        c->oom_adjust_set = false;
-        c->nice = 0;
-        c->nice_set = false;
         c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
-        c->ioprio_set = false;
         c->cpu_sched_policy = SCHED_OTHER;
-        c->cpu_sched_priority = 0;
-        c->cpu_sched_set = false;
-        CPU_ZERO(&c->cpu_affinity);
-        c->cpu_affinity_set = false;
-        c->timer_slack_ns = 0;
-        c->timer_slack_ns_set = false;
-
-        c->cpu_sched_reset_on_fork = false;
-        c->non_blocking = false;
-
-        c->std_input = 0;
-        c->std_output = 0;
-        c->std_error = 0;
         c->syslog_priority = LOG_DAEMON|LOG_INFO;
-
-        c->secure_bits = 0;
-        c->capability_bounding_set_drop = 0;
+        c->mount_flags = MS_SHARED;
 }
 
 void exec_context_done(ExecContext *c) {
@@ -1055,6 +1122,15 @@ void exec_context_done(ExecContext *c) {
                 cap_free(c->capabilities);
                 c->capabilities = NULL;
         }
+
+        strv_free(c->read_only_dirs);
+        c->read_only_dirs = NULL;
+
+        strv_free(c->read_write_dirs);
+        c->read_write_dirs = NULL;
+
+        strv_free(c->inaccessible_dirs);
+        c->inaccessible_dirs = NULL;
 }
 
 void exec_command_done(ExecCommand *c) {
@@ -1093,6 +1169,15 @@ void exec_command_free_array(ExecCommand **c, unsigned n) {
         }
 }
 
+static void strv_fprintf(FILE *f, char **l) {
+        char **g;
+
+        assert(f);
+
+        STRV_FOREACH(g, l)
+                fprintf(f, " %s", *g);
+}
+
 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
         char ** e;
         unsigned i;
@@ -1107,11 +1192,13 @@ void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
                 "%sUMask: %04o\n"
                 "%sWorkingDirectory: %s\n"
                 "%sRootDirectory: %s\n"
-                "%sNonBlocking: %s\n",
+                "%sNonBlocking: %s\n"
+                "%sPrivateTmp: %s\n",
                 prefix, c->umask,
                 prefix, c->working_directory ? c->working_directory : "/",
                 prefix, c->root_directory ? c->root_directory : "/",
-                prefix, yes_no(c->non_blocking));
+                prefix, yes_no(c->non_blocking),
+                prefix, yes_no(c->private_tmp));
 
         if (c->environment)
                 for (e = c->environment; *e; e++)
@@ -1219,14 +1306,27 @@ void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
         if (c->group)
                 fprintf(f, "%sGroup: %s", prefix, c->group);
 
-        if (c->supplementary_groups) {
-                char **g;
-
+        if (strv_length(c->supplementary_groups) > 0) {
                 fprintf(f, "%sSupplementaryGroups:", prefix);
+                strv_fprintf(f, c->supplementary_groups);
+                fputs("\n", f);
+        }
+
+        if (strv_length(c->read_write_dirs) > 0) {
+                fprintf(f, "%sReadWriteDirs:", prefix);
+                strv_fprintf(f, c->read_write_dirs);
+                fputs("\n", f);
+        }
 
-                STRV_FOREACH(g, c->supplementary_groups)
-                        fprintf(f, " %s", *g);
+        if (strv_length(c->read_only_dirs) > 0) {
+                fprintf(f, "%sReadOnlyDirs:", prefix);
+                strv_fprintf(f, c->read_only_dirs);
+                fputs("\n", f);
+        }
 
+        if (strv_length(c->inaccessible_dirs) > 0) {
+                fprintf(f, "%sInaccessibleDirs:", prefix);
+                strv_fprintf(f, c->inaccessible_dirs);
                 fputs("\n", f);
         }
 }
@@ -1272,23 +1372,22 @@ void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
                         prefix, s->status);
 }
 
-char *exec_command_line(ExecCommand *c) {
+char *exec_command_line(char **argv) {
         size_t k;
         char *n, *p, **a;
         bool first = true;
 
-        assert(c);
-        assert(c->argv);
+        assert(argv);
 
         k = 1;
-        STRV_FOREACH(a, c->argv)
+        STRV_FOREACH(a, argv)
                 k += strlen(*a)+3;
 
         if (!(n = new(char, k)))
                 return NULL;
 
         p = n;
-        STRV_FOREACH(a, c->argv) {
+        STRV_FOREACH(a, argv) {
 
                 if (!first)
                         *(p++) = ' ';
@@ -1326,7 +1425,7 @@ void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
         p2 = strappend(prefix, "\t");
         prefix2 = p2 ? p2 : prefix;
 
-        cmd = exec_command_line(c);
+        cmd = exec_command_line(c->argv);
 
         fprintf(f,
                 "%sCommand Line: %s\n",
@@ -1500,7 +1599,8 @@ static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
         [EXEC_INPUT_NULL] = "null",
         [EXEC_INPUT_TTY] = "tty",
         [EXEC_INPUT_TTY_FORCE] = "tty-force",
-        [EXEC_INPUT_TTY_FAIL] = "tty-fail"
+        [EXEC_INPUT_TTY_FAIL] = "tty-fail",
+        [EXEC_INPUT_SOCKET] = "socket"
 };
 
 static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
@@ -1508,7 +1608,8 @@ static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
         [EXEC_OUTPUT_NULL] = "null",
         [EXEC_OUTPUT_TTY] = "tty",
         [EXEC_OUTPUT_SYSLOG] = "syslog",
-        [EXEC_OUTPUT_KERNEL] = "kernel"
+        [EXEC_OUTPUT_KERNEL] = "kernel",
+        [EXEC_OUTPUT_SOCKET] = "socket"
 };
 
 DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);