diff options
Diffstat (limited to 'execute.c')
| -rw-r--r-- | execute.c | 240 |
1 files changed, 225 insertions, 15 deletions
@@ -1,41 +1,238 @@ /*-*- Mode: C; c-basic-offset: 8 -*-*/ #include <assert.h> +#include <dirent.h> +#include <errno.h> +#include <fcntl.h> +#include <unistd.h> #include "execute.h" #include "strv.h" #include "macro.h" #include "util.h" -int exec_spawn(const ExecCommand *command, const ExecContext *context, pid_t *ret) { +static int close_fds(int except[], unsigned n_except) { + DIR *d; + struct dirent *de; + int r = 0; + + /* Modifies the fds array! (sorts it) */ + + if (!(d = opendir("/proc/self/fd"))) + return -errno; + + while ((de = readdir(d))) { + int fd; + + if (de->d_name[0] == '.') + continue; + + if ((r = safe_atoi(de->d_name, &fd)) < 0) + goto finish; + + if (fd < 3) + continue; + + if (fd == dirfd(d)) + continue; + + if (except) { + bool found; + unsigned i; + + found = false; + for (i = 0; i < n_except; i++) + if (except[i] == fd) { + found = true; + break; + } + + if (found) + continue; + } + + if ((r = close_nointr(fd)) < 0) + goto finish; + } + +finish: + closedir(d); + return r; +} + +static int shift_fds(int fds[], unsigned n_fds) { + int start, restart_from; + + if (n_fds <= 0) + return 0; + + assert(fds); + + start = 0; + for (;;) { + int i; + + restart_from = -1; + + for (i = start; i < (int) n_fds; i++) { + int nfd; + + /* Already at right index? */ + if (fds[i] == i+3) + continue; + + if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0) + return -errno; + + assert_se(close_nointr(fds[i])); + fds[i] = nfd; + + /* Hmm, the fd we wanted isn't free? Then + * let's remember that and try again from here*/ + if (nfd != i+3 && restart_from < 0) + restart_from = i; + } + + if (restart_from < 0) + break; + + start = restart_from; + } + + return 0; +} + +int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, unsigned n_fds, pid_t *ret) { + pid_t pid; + assert(command); assert(context); assert(ret); + assert(fds || n_fds <= 0); + + if ((pid = fork()) < 0) + return -errno; + + if (pid == 0) { + char **e, **f = NULL; + int i, r; + char t[16]; + /* child */ + umask(context->umask); + + if (chdir(context->directory ? context->directory : "/") < 0) { + r = EXIT_CHDIR; + goto fail; + } + + snprintf(t, sizeof(t), "%i", context->oom_adjust); + char_array_0(t); + + if (write_one_line_file("/proc/self/oom_adj", t) < 0) { + r = EXIT_OOM_ADJUST; + goto fail; + } + + if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) { + r = EXIT_NICE; + goto fail; + } + + if (close_fds(fds, n_fds) < 0 || + shift_fds(fds, n_fds) < 0) { + r = EXIT_FDS; + goto fail; + } + + for (i = 0; i < RLIMIT_NLIMITS; i++) { + if (!context->rlimit[i]) + continue; + + if (setrlimit(i, context->rlimit[i]) < 0) { + r = EXIT_LIMITS; + goto fail; + } + } + + if (n_fds > 0) { + char a[64], b[64]; + char *listen_env[3] = { + a, + b, + NULL + }; + + snprintf(a, sizeof(a), "LISTEN_PID=%llu", (unsigned long long) getpid()); + snprintf(b, sizeof(b), "LISTEN_FDS=%u", n_fds); + + a[sizeof(a)-1] = 0; + b[sizeof(b)-1] = 0; + + if (context->environment) { + if (!(f = strv_merge(listen_env, context->environment))) { + r = EXIT_MEMORY; + goto fail; + } + e = f; + } else + e = listen_env; + + } else + e = context->environment; + + execve(command->path, command->argv, e); + r = EXIT_EXEC; + + fail: + strv_free(f); + _exit(r); + } + + *ret = pid; return 0; } -void exec_context_free(ExecContext *c) { +void exec_context_init(ExecContext *c) { + assert(c); + + c->umask = 0002; + cap_clear(c->capabilities); + c->oom_adjust = 0; + c->nice = 0; +} + +void exec_context_done(ExecContext *c) { unsigned l; assert(c); strv_free(c->environment); + c->environment = NULL; - for (l = 0; l < ELEMENTSOF(c->rlimit); l++) + for (l = 0; l < ELEMENTSOF(c->rlimit); l++) { free(c->rlimit[l]); + c->rlimit[l] = NULL; + } + + free(c->directory); + c->directory = NULL; - free(c->chdir); free(c->user); + c->user = NULL; + free(c->group); - free(c->supplementary_groups); + c->group = NULL; + + strv_free(c->supplementary_groups); + c->supplementary_groups = NULL; } void exec_command_free_list(ExecCommand *c) { ExecCommand *i; while ((i = c)) { - LIST_REMOVE(ExecCommand, c, i); + LIST_REMOVE(ExecCommand, command, c, i); free(i->path); free(i->argv); @@ -43,6 +240,16 @@ void exec_command_free_list(ExecCommand *c) { } } +void exec_command_free_array(ExecCommand **c, unsigned n) { + unsigned i; + + for (i = 0; i < n; i++) { + exec_command_free_list(c[i]); + c[i] = NULL; + } +} + + void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) { assert(c); assert(f); @@ -52,17 +259,20 @@ void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) { fprintf(f, "%sUmask: %04o\n" - "%sDumpable: %s\n" - "%sDirectory: %s\n", + "%sDirectory: %s\n" + "%sNice: %i\n" + "%sOOMAdjust: %i\n", prefix, c->umask, - prefix, yes_no(c->dumpable), - prefix, c->chdir ? c->chdir : "/"); + prefix, c->directory ? c->directory : "/", + prefix, c->nice, + prefix, c->oom_adjust); } -void exec_context_defaults(ExecContext *c) { - assert(c); +void exec_status_fill(ExecStatus *s, pid_t pid, int code, int status) { + assert(s); - c->umask = 0002; - cap_clear(c->capabilities); - c->dumpable = true; + s->pid = pid; + s->code = code; + s->status = status; + s->timestamp = now(CLOCK_REALTIME); } |