X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=execute.c;h=ccf951a25a437974f681ca0d12763237dfe9839c;hb=d46de8a1a249e179687361dcaeba27e1c586253a;hp=bcaa4e959d580c0d3ed65a9f5615b1e2367f416d;hpb=44d8db9e5aa86165c97289f6c78a7e42bac78362;p=elogind.git diff --git a/execute.c b/execute.c index bcaa4e959..ccf951a25 100644 --- a/execute.c +++ b/execute.c @@ -6,11 +6,15 @@ #include #include #include +#include +#include +#include #include "execute.h" #include "strv.h" #include "macro.h" #include "util.h" +#include "log.h" static int close_fds(int except[], unsigned n_except) { DIR *d; @@ -85,7 +89,7 @@ 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])); + assert_se(close_nointr(fds[i]) == 0); fds[i] = nfd; /* Hmm, the fd we wanted isn't free? Then @@ -103,6 +107,146 @@ static int shift_fds(int fds[], unsigned n_fds) { return 0; } +static int flags_fds(int fds[], unsigned n_fds) { + unsigned i; + + if (n_fds <= 0) + return 0; + + assert(fds); + + /* Drops O_NONBLOCK and FD_CLOEXEC from the file flags */ + + for (i = 0; i < n_fds; i++) { + int flags; + + if ((flags = fcntl(fds[i], F_GETFL, 0)) < 0) + return -errno; + + /* Since we are at it, let's make sure that nobody + * forgot setting O_NONBLOCK for all our fds */ + + if (fcntl(fds[i], F_SETFL, flags &~O_NONBLOCK) < 0) + return -errno; + + if ((flags = fcntl(fds[i], F_GETFD, 0)) < 0) + return -errno; + + /* Also make sure nobody forgot O_CLOEXEC for all our + * fds */ + if (fcntl(fds[i], F_SETFD, flags &~FD_CLOEXEC) < 0) + return -errno; + } + + return 0; +} + +static int replace_null_fd(int fd, int flags) { + int nfd; + assert(fd >= 0); + + close_nointr(fd); + + if ((nfd = open("/dev/null", flags|O_NOCTTY)) < 0) + return -errno; + + if (nfd != fd) { + close_nointr_nofail(nfd); + return -EIO; + } + + return 0; +} + +static int setup_output(const ExecContext *context, const char *ident) { + int r; + + assert(context); + + switch (context->output) { + + case EXEC_CONSOLE: + return 0; + + case EXEC_NULL: + + if ((r = replace_null_fd(STDIN_FILENO, O_RDONLY)) < 0 || + (r = replace_null_fd(STDOUT_FILENO, O_WRONLY)) < 0 || + (r = replace_null_fd(STDERR_FILENO, O_WRONLY)) < 0) + return r; + + return 0; + + case EXEC_KERNEL: + case EXEC_SYSLOG: { + + int fd; + union { + struct sockaddr sa; + struct sockaddr_un un; + } sa; + + if ((r = replace_null_fd(STDIN_FILENO, O_RDONLY)) < 0) + return r; + + close_nointr(STDOUT_FILENO); + close_nointr(STDERR_FILENO); + + if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) + return -errno; + + if (fd != STDOUT_FILENO) { + close_nointr_nofail(fd); + return -EIO; + } + + zero(sa); + sa.sa.sa_family = AF_UNIX; + strncpy(sa.un.sun_path+1, LOGGER_SOCKET, sizeof(sa.un.sun_path)-1); + + if (connect(fd, &sa.sa, sizeof(sa)) < 0) { + close_nointr_nofail(fd); + return -errno; + } + + if (shutdown(fd, SHUT_RD) < 0) { + close_nointr_nofail(fd); + return -errno; + } + + if ((fd = dup(fd)) < 0) { + close_nointr_nofail(fd); + return -errno; + } + + if (fd != STDERR_FILENO) { + close_nointr_nofail(fd); + return -EIO; + } + + /* We speak a very simple protocol between log server + * and client: one line for the log destination (kmsg + * or syslog), followed by the priority field, + * followed by the process name. Since we replaced + * stdin/stderr we simple use stdio to write to + * it. Note that we use stderr, to minimize buffer + * flushing issues. */ + + fprintf(stderr, + "%s\n" + "%i\n" + "%s\n", + context->output == EXEC_KERNEL ? "kmsg" : "syslog", + context->syslog_priority, + context->syslog_identifier ? context->syslog_identifier : ident); + + return 0; + } + } + + assert_not_reached("Unknown logging type"); +} + int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, unsigned n_fds, pid_t *ret) { pid_t pid; @@ -111,6 +255,8 @@ int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, assert(ret); assert(fds || n_fds <= 0); + log_debug("about to execute %s", command->path); + if ((pid = fork()) < 0) return -errno; @@ -118,8 +264,16 @@ int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, char **e, **f = NULL; int i, r; char t[16]; + sigset_t ss; + /* child */ + if (sigemptyset(&ss) < 0 || + sigprocmask(SIG_SETMASK, &ss, NULL) < 0) { + r = EXIT_SIGNAL_MASK; + goto fail; + } + umask(context->umask); if (chdir(context->directory ? context->directory : "/") < 0) { @@ -127,6 +281,11 @@ int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, goto fail; } + if (setup_output(context, file_name_from_path(command->path)) < 0) { + r = EXIT_OUTPUT; + goto fail; + } + snprintf(t, sizeof(t), "%i", context->oom_adjust); char_array_0(t); @@ -141,7 +300,8 @@ int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, } if (close_fds(fds, n_fds) < 0 || - shift_fds(fds, n_fds) < 0) { + shift_fds(fds, n_fds) < 0 || + flags_fds(fds, n_fds) < 0) { r = EXIT_FDS; goto fail; } @@ -190,6 +350,9 @@ int exec_spawn(const ExecCommand *command, const ExecContext *context, int *fds, _exit(r); } + + log_debug("executed %s as %llu", command->path, (unsigned long long) pid); + *ret = pid; return 0; } @@ -201,6 +364,9 @@ void exec_context_init(ExecContext *c) { cap_clear(c->capabilities); c->oom_adjust = 0; c->nice = 0; + + c->output = 0; + c->syslog_priority = LOG_DAEMON|LOG_INFO; } void exec_context_done(ExecContext *c) { @@ -219,6 +385,9 @@ void exec_context_done(ExecContext *c) { free(c->directory); c->directory = NULL; + free(c->syslog_identifier); + c->syslog_identifier = NULL; + free(c->user); c->user = NULL; @@ -250,7 +419,6 @@ void exec_command_free_array(ExecCommand **c, unsigned n) { } } - void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) { assert(c); assert(f); @@ -286,7 +454,7 @@ char *exec_command_line(ExecCommand *c) { assert(c); assert(c->argv); - k = 0; + k = 1; STRV_FOREACH(a, c->argv) k += strlen(*a)+3; @@ -310,6 +478,8 @@ char *exec_command_line(ExecCommand *c) { } + *p = 0; + /* FIXME: this doesn't really handle arguments that have * spaces and ticks in them */