X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Futil.c;h=9fd2d89556819500d9c602cce6f99a60cf45c02c;hp=cb9687cb02085703fa4416d083625abacc65c3d9;hb=45030287af1e8e76b0feb1cfc3011a0ef2b37d0d;hpb=a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8 diff --git a/src/shared/util.c b/src/shared/util.c index cb9687cb0..9fd2d8955 100644 --- a/src/shared/util.c +++ b/src/shared/util.c @@ -39,7 +39,6 @@ #include #include #include -#include #include #include #include @@ -60,7 +59,10 @@ #include #include #include +#include #include +#include +#include #undef basename #ifdef HAVE_SYS_AUXV_H @@ -85,6 +87,7 @@ #include "gunicode.h" #include "virt.h" #include "def.h" +#include "sparse-endian.h" int saved_argc = 0; char **saved_argv = NULL; @@ -140,48 +143,122 @@ char* endswith(const char *s, const char *postfix) { return (char*) s + sl - pl; } -bool first_word(const char *s, const char *word) { +char* first_word(const char *s, const char *word) { size_t sl, wl; + const char *p; assert(s); assert(word); + /* Checks if the string starts with the specified word, either + * followed by NUL or by whitespace. Returns a pointer to the + * NUL or the first character after the whitespace. */ + sl = strlen(s); wl = strlen(word); if (sl < wl) - return false; + return NULL; if (wl == 0) - return true; + return (char*) s; if (memcmp(s, word, wl) != 0) - return false; + return NULL; + + p = s + wl; + if (*p == 0) + return (char*) p; - return s[wl] == 0 || - strchr(WHITESPACE, s[wl]); + if (!strchr(WHITESPACE, *p)) + return NULL; + + p += strspn(p, WHITESPACE); + return (char*) p; } -int close_nointr(int fd) { - int r; +static size_t cescape_char(char c, char *buf) { + char * buf_old = buf; + + switch (c) { + + case '\a': + *(buf++) = '\\'; + *(buf++) = 'a'; + break; + case '\b': + *(buf++) = '\\'; + *(buf++) = 'b'; + break; + case '\f': + *(buf++) = '\\'; + *(buf++) = 'f'; + break; + case '\n': + *(buf++) = '\\'; + *(buf++) = 'n'; + break; + case '\r': + *(buf++) = '\\'; + *(buf++) = 'r'; + break; + case '\t': + *(buf++) = '\\'; + *(buf++) = 't'; + break; + case '\v': + *(buf++) = '\\'; + *(buf++) = 'v'; + break; + case '\\': + *(buf++) = '\\'; + *(buf++) = '\\'; + break; + case '"': + *(buf++) = '\\'; + *(buf++) = '"'; + break; + case '\'': + *(buf++) = '\\'; + *(buf++) = '\''; + break; + + default: + /* For special chars we prefer octal over + * hexadecimal encoding, simply because glib's + * g_strescape() does the same */ + if ((c < ' ') || (c >= 127)) { + *(buf++) = '\\'; + *(buf++) = octchar((unsigned char) c >> 6); + *(buf++) = octchar((unsigned char) c >> 3); + *(buf++) = octchar((unsigned char) c); + } else + *(buf++) = c; + break; + } + + return buf - buf_old; +} +int close_nointr(int fd) { assert(fd >= 0); - r = close(fd); - if (r >= 0) - return r; - else if (errno == EINTR) - /* - * Just ignore EINTR; a retry loop is the wrong - * thing to do on Linux. - * - * http://lkml.indiana.edu/hypermail/linux/kernel/0509.1/0877.html - * https://bugzilla.gnome.org/show_bug.cgi?id=682819 - * http://utcc.utoronto.ca/~cks/space/blog/unix/CloseEINTR - * https://sites.google.com/site/michaelsafyan/software-engineering/checkforeintrwheninvokingclosethinkagain - */ + + if (close(fd) >= 0) return 0; - else - return -errno; + + /* + * Just ignore EINTR; a retry loop is the wrong thing to do on + * Linux. + * + * http://lkml.indiana.edu/hypermail/linux/kernel/0509.1/0877.html + * https://bugzilla.gnome.org/show_bug.cgi?id=682819 + * http://utcc.utoronto.ca/~cks/space/blog/unix/CloseEINTR + * https://sites.google.com/site/michaelsafyan/software-engineering/checkforeintrwheninvokingclosethinkagain + */ + if (errno == EINTR) + return 0; + + return -errno; } int safe_close(int fd) { @@ -280,7 +357,7 @@ int parse_uid(const char *s, uid_t* ret_uid) { if ((unsigned long) uid != ul) return -ERANGE; - /* Some libc APIs use (uid_t) -1 as special placeholder */ + /* Some libc APIs use UID_INVALID as special placeholder */ if (uid == (uid_t) 0xFFFFFFFF) return -ENXIO; @@ -352,6 +429,46 @@ int safe_atou8(const char *s, uint8_t *ret) { return 0; } +int safe_atou16(const char *s, uint16_t *ret) { + char *x = NULL; + unsigned long l; + + assert(s); + assert(ret); + + errno = 0; + l = strtoul(s, &x, 0); + + if (!x || x == s || *x || errno) + return errno > 0 ? -errno : -EINVAL; + + if ((unsigned long) (uint16_t) l != l) + return -ERANGE; + + *ret = (uint16_t) l; + return 0; +} + +int safe_atoi16(const char *s, int16_t *ret) { + char *x = NULL; + long l; + + assert(s); + assert(ret); + + errno = 0; + l = strtol(s, &x, 0); + + if (!x || x == s || *x || errno) + return errno > 0 ? -errno : -EINVAL; + + if ((long) (int16_t) l != l) + return -ERANGE; + + *ret = (int16_t) l; + return 0; +} + int safe_atollu(const char *s, long long unsigned *ret_llu) { char *x = NULL; unsigned long long l; @@ -407,7 +524,7 @@ int safe_atod(const char *s, double *ret_d) { static size_t strcspn_escaped(const char *s, const char *reject) { bool escaped = false; - size_t n; + int n; for (n=0; s[n]; n++) { if (escaped) @@ -417,6 +534,7 @@ static size_t strcspn_escaped(const char *s, const char *reject) { else if (strchr(reject, s[n])) break; } + /* if s ends in \, return index of previous char */ return n - escaped; } @@ -444,7 +562,7 @@ const char* split(const char **state, size_t *l, const char *separator, bool quo *l = strcspn_escaped(current + 1, quotechars); if (current[*l + 1] == '\0' || (current[*l + 2] && !strchr(separator, current[*l + 2]))) { - /* right quote missing or garbage at the end*/ + /* right quote missing or garbage at the end */ *state = current; return NULL; } @@ -452,6 +570,11 @@ const char* split(const char **state, size_t *l, const char *separator, bool quo *state = current++ + *l + 2; } else if (quoted) { *l = strcspn_escaped(current, separator); + if (current[*l] && !strchr(separator, current[*l])) { + /* unfinished escape */ + *state = current; + return NULL; + } *state = current + *l; } else { *l = strcspn(current, separator); @@ -504,56 +627,6 @@ int get_parent_of_pid(pid_t pid, pid_t *_ppid) { return 0; } -int get_starttime_of_pid(pid_t pid, unsigned long long *st) { - int r; - _cleanup_free_ char *line = NULL; - const char *p; - - assert(pid >= 0); - assert(st); - - p = procfs_file_alloca(pid, "stat"); - r = read_one_line_file(p, &line); - if (r < 0) - return r; - - /* Let's skip the pid and comm fields. The latter is enclosed - * in () but does not escape any () in its value, so let's - * skip over it manually */ - - p = strrchr(line, ')'); - if (!p) - return -EIO; - - p++; - - if (sscanf(p, " " - "%*c " /* state */ - "%*d " /* ppid */ - "%*d " /* pgrp */ - "%*d " /* session */ - "%*d " /* tty_nr */ - "%*d " /* tpgid */ - "%*u " /* flags */ - "%*u " /* minflt */ - "%*u " /* cminflt */ - "%*u " /* majflt */ - "%*u " /* cmajflt */ - "%*u " /* utime */ - "%*u " /* stime */ - "%*d " /* cutime */ - "%*d " /* cstime */ - "%*d " /* priority */ - "%*d " /* nice */ - "%*d " /* num_threads */ - "%*d " /* itrealvalue */ - "%llu " /* starttime */, - st) != 1) - return -EIO; - - return 0; -} - int fchmod_umask(int fd, mode_t m) { mode_t u; int r; @@ -684,7 +757,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * } /* Kernel threads have no argv[] */ - if (r == NULL || r[0] == 0) { + if (isempty(r)) { _cleanup_free_ char *t = NULL; int h; @@ -746,19 +819,30 @@ int get_process_capeff(pid_t pid, char **capeff) { return get_status_field(p, "\nCapEff:", capeff); } +static int get_process_link_contents(const char *proc_file, char **name) { + int r; + + assert(proc_file); + assert(name); + + r = readlink_malloc(proc_file, name); + if (r < 0) + return r == -ENOENT ? -ESRCH : r; + + return 0; +} + int get_process_exe(pid_t pid, char **name) { const char *p; char *d; int r; assert(pid >= 0); - assert(name); p = procfs_file_alloca(pid, "exe"); - - r = readlink_malloc(p, name); + r = get_process_link_contents(p, name); if (r < 0) - return r == -ENOENT ? -ESRCH : r; + return r; d = endswith(*name, " (deleted)"); if (d) @@ -810,6 +894,59 @@ int get_process_gid(pid_t pid, gid_t *gid) { return get_process_id(pid, "Gid:", gid); } +int get_process_cwd(pid_t pid, char **cwd) { + const char *p; + + assert(pid >= 0); + + p = procfs_file_alloca(pid, "cwd"); + + return get_process_link_contents(p, cwd); +} + +int get_process_root(pid_t pid, char **root) { + const char *p; + + assert(pid >= 0); + + p = procfs_file_alloca(pid, "root"); + + return get_process_link_contents(p, root); +} + +int get_process_environ(pid_t pid, char **env) { + _cleanup_fclose_ FILE *f = NULL; + _cleanup_free_ char *outcome = NULL; + int c; + const char *p; + size_t allocated = 0, sz = 0; + + assert(pid >= 0); + assert(env); + + p = procfs_file_alloca(pid, "environ"); + + f = fopen(p, "re"); + if (!f) + return -errno; + + while ((c = fgetc(f)) != EOF) { + if (!GREEDY_REALLOC(outcome, allocated, sz + 5)) + return -ENOMEM; + + if (c == '\0') + outcome[sz++] = '\n'; + else + sz += cescape_char(c, outcome + sz); + } + + outcome[sz] = '\0'; + *env = outcome; + outcome = NULL; + + return 0; +} + char *strnappend(const char *s, const char *suffix, size_t b) { size_t a; char *r; @@ -882,6 +1019,28 @@ int readlink_malloc(const char *p, char **ret) { return readlinkat_malloc(AT_FDCWD, p, ret); } +int readlink_value(const char *p, char **ret) { + _cleanup_free_ char *link = NULL; + char *value; + int r; + + r = readlink_malloc(p, &link); + if (r < 0) + return r; + + value = basename(link); + if (!value) + return -ENOENT; + + value = strdup(value); + if (!value) + return -ENOMEM; + + *ret = value; + + return 0; +} + int readlink_and_make_absolute(const char *p, char **r) { _cleanup_free_ char *target = NULL; char *k; @@ -926,7 +1085,7 @@ int readlink_and_canonicalize(const char *p, char **r) { } int reset_all_signal_handlers(void) { - int sig; + int sig, r = 0; for (sig = 1; sig < _NSIG; sig++) { struct sigaction sa = { @@ -934,16 +1093,29 @@ int reset_all_signal_handlers(void) { .sa_flags = SA_RESTART, }; + /* These two cannot be caught... */ if (sig == SIGKILL || sig == SIGSTOP) continue; /* On Linux the first two RT signals are reserved by * glibc, and sigaction() will return EINVAL for them. */ if ((sigaction(sig, &sa, NULL) < 0)) - if (errno != EINVAL) - return -errno; + if (errno != EINVAL && r == 0) + r = -errno; } + return r; +} + +int reset_signal_mask(void) { + sigset_t ss; + + if (sigemptyset(&ss) < 0) + return -errno; + + if (sigprocmask(SIG_SETMASK, &ss, NULL) < 0) + return -errno; + return 0; } @@ -982,7 +1154,7 @@ char *delete_chars(char *s, const char *bad) { } char *file_in_same_dir(const char *path, const char *filename) { - char *e, *r; + char *e, *ret; size_t k; assert(path); @@ -995,17 +1167,17 @@ char *file_in_same_dir(const char *path, const char *filename) { if (path_is_absolute(filename)) return strdup(filename); - if (!(e = strrchr(path, '/'))) + e = strrchr(path, '/'); + if (!e) return strdup(filename); k = strlen(filename); - if (!(r = new(char, e-path+1+k+1))) + ret = new(char, (e + 1 - path) + k + 1); + if (!ret) return NULL; - memcpy(r, path, e-path+1); - memcpy(r+(e-path)+1, filename, k+1); - - return r; + memcpy(mempcpy(ret, path, e + 1 - path), filename, k + 1); + return ret; } int rmdir_parents(const char *path, const char *stop) { @@ -1071,7 +1243,7 @@ int unhexchar(char c) { if (c >= 'A' && c <= 'F') return c - 'A' + 10; - return -1; + return -EINVAL; } char *hexmem(const void *p, size_t l) { @@ -1126,7 +1298,7 @@ int unoctchar(char c) { if (c >= '0' && c <= '7') return c - '0'; - return -1; + return -EINVAL; } char decchar(int x) { @@ -1138,7 +1310,7 @@ int undecchar(char c) { if (c >= '0' && c <= '9') return c - '0'; - return -1; + return -EINVAL; } char *cescape(const char *s) { @@ -1154,63 +1326,7 @@ char *cescape(const char *s) { return NULL; for (f = s, t = r; *f; f++) - - switch (*f) { - - case '\a': - *(t++) = '\\'; - *(t++) = 'a'; - break; - case '\b': - *(t++) = '\\'; - *(t++) = 'b'; - break; - case '\f': - *(t++) = '\\'; - *(t++) = 'f'; - break; - case '\n': - *(t++) = '\\'; - *(t++) = 'n'; - break; - case '\r': - *(t++) = '\\'; - *(t++) = 'r'; - break; - case '\t': - *(t++) = '\\'; - *(t++) = 't'; - break; - case '\v': - *(t++) = '\\'; - *(t++) = 'v'; - break; - case '\\': - *(t++) = '\\'; - *(t++) = '\\'; - break; - case '"': - *(t++) = '\\'; - *(t++) = '"'; - break; - case '\'': - *(t++) = '\\'; - *(t++) = '\''; - break; - - default: - /* For special chars we prefer octal over - * hexadecimal encoding, simply because glib's - * g_strescape() does the same */ - if ((*f < ' ') || (*f >= 127)) { - *(t++) = '\\'; - *(t++) = octchar((unsigned char) *f >> 6); - *(t++) = octchar((unsigned char) *f >> 3); - *(t++) = octchar((unsigned char) *f); - } else - *(t++) = *f; - break; - } + t += cescape_char(*f, t); *t = 0; @@ -1230,18 +1346,25 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre r = new(char, pl+length+1); if (!r) - return r; + return NULL; if (prefix) memcpy(r, prefix, pl); for (f = s, t = r + pl; f < s + length; f++) { + size_t remaining = s + length - f; + assert(remaining > 0); - if (*f != '\\') { + if (*f != '\\') { /* a literal literal */ *(t++) = *f; continue; } + if (--remaining == 0) { /* copy trailing backslash verbatim */ + *(t++) = *f; + break; + } + f++; switch (*f) { @@ -1284,10 +1407,12 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre case 'x': { /* hexadecimal encoding */ - int a, b; + int a = -1, b = -1; - a = unhexchar(f[1]); - b = unhexchar(f[2]); + if (remaining >= 2) { + a = unhexchar(f[1]); + b = unhexchar(f[2]); + } if (a < 0 || b < 0 || (a == 0 && b == 0)) { /* Invalid escape code, let's take it literal then */ @@ -1310,11 +1435,13 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre case '6': case '7': { /* octal encoding */ - int a, b, c; + int a = -1, b = -1, c = -1; - a = unoctchar(f[0]); - b = unoctchar(f[1]); - c = unoctchar(f[2]); + if (remaining >= 3) { + a = unoctchar(f[0]); + b = unoctchar(f[1]); + c = unoctchar(f[2]); + } if (a < 0 || b < 0 || c < 0 || (a == 0 && b == 0 && c == 0)) { /* Invalid escape code, let's take it literal then */ @@ -1328,11 +1455,6 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre break; } - case 0: - /* premature end of string.*/ - *(t++) = '\\'; - goto finish; - default: /* Invalid escape code, let's take it literal then */ *(t++) = '\\'; @@ -1341,7 +1463,6 @@ char *cunescape_length_with_prefix(const char *s, size_t length, const char *pre } } -finish: *t = 0; return r; } @@ -1397,7 +1518,7 @@ char *ascii_strlower(char *t) { return t; } -_pure_ static bool ignore_file_allow_backup(const char *filename) { +_pure_ static bool hidden_file_allow_backup(const char *filename) { assert(filename); return @@ -1410,16 +1531,17 @@ _pure_ static bool ignore_file_allow_backup(const char *filename) { endswith(filename, ".rpmorig") || endswith(filename, ".dpkg-old") || endswith(filename, ".dpkg-new") || + endswith(filename, ".dpkg-tmp") || endswith(filename, ".swp"); } -bool ignore_file(const char *filename) { +bool hidden_file(const char *filename) { assert(filename); if (endswith(filename, "~")) return true; - return ignore_file_allow_backup(filename); + return hidden_file_allow_backup(filename); } int fd_nonblock(int fd, bool nonblock) { @@ -1513,7 +1635,7 @@ int close_all_fds(const int except[], unsigned n_except) { while ((de = readdir(d))) { int fd = -1; - if (ignore_file(de->d_name)) + if (hidden_file(de->d_name)) continue; if (safe_atoi(de->d_name, &fd) < 0) @@ -1853,9 +1975,6 @@ int open_terminal(const char *name, int mode) { c++; } - if (fd < 0) - return -errno; - r = isatty(fd); if (r < 0) { safe_close(fd); @@ -1995,9 +2114,9 @@ int acquire_terminal( assert(notify >= 0); for (;;) { - uint8_t inotify_buffer[sizeof(struct inotify_event) + FILENAME_MAX]; - ssize_t l; + union inotify_event_buffer buffer; struct inotify_event *e; + ssize_t l; if (timeout != USEC_INFINITY) { usec_t n; @@ -2018,9 +2137,8 @@ int acquire_terminal( } } - l = read(notify, inotify_buffer, sizeof(inotify_buffer)); + l = read(notify, &buffer, sizeof(buffer)); if (l < 0) { - if (errno == EINTR || errno == EAGAIN) continue; @@ -2028,21 +2146,11 @@ int acquire_terminal( goto fail; } - e = (struct inotify_event*) inotify_buffer; - - while (l > 0) { - size_t step; - + FOREACH_INOTIFY_EVENT(e, buffer, l) { if (e->wd != wd || !(e->mask & IN_CLOSE)) { r = -EIO; goto fail; } - - step = sizeof(struct inotify_event) + e->len; - assert(step <= (size_t) l); - - e = (struct inotify_event*) ((uint8_t*) e + step); - l -= step; } break; @@ -2052,14 +2160,14 @@ int acquire_terminal( * ended our handle will be dead. It's important that * we do this after sleeping, so that we don't enter * an endless loop. */ - safe_close(fd); + fd = safe_close(fd); } safe_close(notify); r = reset_terminal_fd(fd, true); if (r < 0) - log_warning("Failed to reset terminal: %s", strerror(-r)); + log_warning_errno(r, "Failed to reset terminal: %m"); return fd; @@ -2071,12 +2179,14 @@ fail: } int release_terminal(void) { - int r = 0; - struct sigaction sa_old, sa_new = { + static const struct sigaction sa_new = { .sa_handler = SIG_IGN, .sa_flags = SA_RESTART, }; - _cleanup_close_ int fd; + + _cleanup_close_ int fd = -1; + struct sigaction sa_old; + int r = 0; fd = open("/dev/tty", O_RDWR|O_NOCTTY|O_NDELAY|O_CLOEXEC); if (fd < 0) @@ -2172,21 +2282,25 @@ ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) { ssize_t k; k = read(fd, p, nbytes); - if (k < 0 && errno == EINTR) - continue; + if (k < 0) { + if (errno == EINTR) + continue; - if (k < 0 && errno == EAGAIN && do_poll) { + if (errno == EAGAIN && do_poll) { - /* We knowingly ignore any return value here, - * and expect that any error/EOF is reported - * via read() */ + /* We knowingly ignore any return value here, + * and expect that any error/EOF is reported + * via read() */ - fd_wait_for_event(fd, POLLIN, USEC_INFINITY); - continue; + fd_wait_for_event(fd, POLLIN, USEC_INFINITY); + continue; + } + + return n > 0 ? n : -errno; } - if (k <= 0) - return n > 0 ? n : (k < 0 ? -errno : 0); + if (k == 0) + return n; p += k; nbytes -= k; @@ -2196,39 +2310,42 @@ ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) { return n; } -ssize_t loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) { +int loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) { const uint8_t *p = buf; - ssize_t n = 0; assert(fd >= 0); assert(buf); + errno = 0; + while (nbytes > 0) { ssize_t k; k = write(fd, p, nbytes); - if (k < 0 && errno == EINTR) - continue; + if (k < 0) { + if (errno == EINTR) + continue; - if (k < 0 && errno == EAGAIN && do_poll) { + if (errno == EAGAIN && do_poll) { + /* We knowingly ignore any return value here, + * and expect that any error/EOF is reported + * via write() */ - /* We knowingly ignore any return value here, - * and expect that any error/EOF is reported - * via write() */ + fd_wait_for_event(fd, POLLOUT, USEC_INFINITY); + continue; + } - fd_wait_for_event(fd, POLLOUT, USEC_INFINITY); - continue; + return -errno; } - if (k <= 0) - return n > 0 ? n : (k < 0 ? -errno : 0); + if (k == 0) /* Can't really happen */ + return -EIO; p += k; nbytes -= k; - n += k; } - return n; + return 0; } int parse_size(const char *t, off_t base, off_t *size) { @@ -2365,9 +2482,9 @@ int make_stdio(int fd) { assert(fd >= 0); - r = dup3(fd, STDIN_FILENO, 0); - s = dup3(fd, STDOUT_FILENO, 0); - t = dup3(fd, STDERR_FILENO, 0); + r = dup2(fd, STDIN_FILENO); + s = dup2(fd, STDOUT_FILENO); + t = dup2(fd, STDERR_FILENO); if (fd >= 3) safe_close(fd); @@ -2375,7 +2492,11 @@ int make_stdio(int fd) { if (r < 0 || s < 0 || t < 0) return -errno; - /* We rely here that the new fd has O_CLOEXEC not set */ + /* Explicitly unset O_CLOEXEC, since if fd was < 3, then + * dup2() was a NOP and the bit hence possibly set. */ + fd_cloexec(STDIN_FILENO, false); + fd_cloexec(STDOUT_FILENO, false); + fd_cloexec(STDERR_FILENO, false); return 0; } @@ -2418,7 +2539,7 @@ int dir_is_empty(const char *path) { if (!de) return 1; - if (!ignore_file(de->d_name)) + if (!hidden_file(de->d_name)) return 0; } } @@ -2442,14 +2563,53 @@ char* dirname_malloc(const char *path) { } int dev_urandom(void *p, size_t n) { - _cleanup_close_ int fd; + static int have_syscall = -1; + int r, fd; ssize_t k; + /* Gathers some randomness from the kernel. This call will + * never block, and will always return some data from the + * kernel, regardless if the random pool is fully initialized + * or not. It thus makes no guarantee for the quality of the + * returned entropy, but is good enough for or usual usecases + * of seeding the hash functions for hashtable */ + + /* Use the getrandom() syscall unless we know we don't have + * it, or when the requested size is too large for it. */ + if (have_syscall != 0 || (size_t) (int) n != n) { + r = getrandom(p, n, GRND_NONBLOCK); + if (r == (int) n) { + have_syscall = true; + return 0; + } + + if (r < 0) { + if (errno == ENOSYS) + /* we lack the syscall, continue with + * reading from /dev/urandom */ + have_syscall = false; + else if (errno == EAGAIN) + /* not enough entropy for now. Let's + * remember to use the syscall the + * next time, again, but also read + * from /dev/urandom for now, which + * doesn't care about the current + * amount of entropy. */ + have_syscall = true; + else + return -errno; + } else + /* too short read? */ + return -EIO; + } + fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY); if (fd < 0) return errno == ENOENT ? -ENOSYS : -errno; k = loop_read(fd, p, n, true); + safe_close(fd); + if (k < 0) return (int) k; if ((size_t) k != n) @@ -2458,8 +2618,36 @@ int dev_urandom(void *p, size_t n) { return 0; } -void random_bytes(void *p, size_t n) { +void initialize_srand(void) { static bool srand_called = false; + unsigned x; +#ifdef HAVE_SYS_AUXV_H + void *auxv; +#endif + + if (srand_called) + return; + + x = 0; + +#ifdef HAVE_SYS_AUXV_H + /* The kernel provides us with a bit of entropy in auxv, so + * let's try to make use of that to seed the pseudo-random + * generator. It's better than nothing... */ + + auxv = (void*) getauxval(AT_RANDOM); + if (auxv) + x ^= *(unsigned*) auxv; +#endif + + x ^= (unsigned) now(CLOCK_REALTIME); + x ^= (unsigned) gettid(); + + srand(x); + srand_called = true; +} + +void random_bytes(void *p, size_t n) { uint8_t *q; int r; @@ -2470,28 +2658,7 @@ void random_bytes(void *p, size_t n) { /* If some idiot made /dev/urandom unavailable to us, he'll * get a PRNG instead. */ - if (!srand_called) { - unsigned x = 0; - -#ifdef HAVE_SYS_AUXV_H - /* The kernel provides us with a bit of entropy in - * auxv, so let's try to make use of that to seed the - * pseudo-random generator. It's better than - * nothing... */ - - void *auxv; - - auxv = (void*) getauxval(AT_RANDOM); - if (auxv) - x ^= *(unsigned*) auxv; -#endif - - x ^= (unsigned) now(CLOCK_REALTIME); - x ^= (unsigned) gettid(); - - srand(x); - srand_called = true; - } + initialize_srand(); for (q = p; q < (uint8_t*) p + n; q ++) *q = rand(); @@ -2577,7 +2744,7 @@ bool hostname_is_set(void) { return !isempty(u.nodename) && !streq(u.nodename, "(none)"); } -static char *lookup_uid(uid_t uid) { +char *lookup_uid(uid_t uid) { long bufsize; char *name; _cleanup_free_ char *buf = NULL; @@ -2626,23 +2793,36 @@ char *getusername_malloc(void) { return lookup_uid(getuid()); } -int getttyname_malloc(int fd, char **r) { - char path[PATH_MAX], *c; - int k; +int getttyname_malloc(int fd, char **ret) { + size_t l = 100; + int r; - assert(r); + assert(fd >= 0); + assert(ret); - k = ttyname_r(fd, path, sizeof(path)); - if (k > 0) - return -k; + for (;;) { + char path[l]; - char_array_0(path); + r = ttyname_r(fd, path, sizeof(path)); + if (r == 0) { + const char *p; + char *c; - c = strdup(startswith(path, "/dev/") ? path + 5 : path); - if (!c) - return -ENOMEM; + p = startswith(path, "/dev/"); + c = strdup(p ?: path); + if (!c) + return -ENOMEM; + + *ret = c; + return 0; + } + + if (r != ERANGE) + return -r; + + l *= 2; + } - *r = c; return 0; } @@ -2713,7 +2893,7 @@ int get_ctty(pid_t pid, dev_t *_devnr, char **r) { if (k < 0) return k; - snprintf(fn, sizeof(fn), "/dev/char/%u:%u", major(devnr), minor(devnr)); + sprintf(fn, "/dev/char/%u:%u", major(devnr), minor(devnr)); k = readlink_malloc(fn, &s); if (k < 0) { @@ -2849,6 +3029,15 @@ _pure_ static int is_temporary_fs(struct statfs *s) { F_TYPE_EQUAL(s->f_type, RAMFS_MAGIC); } +int is_fd_on_temporary_fs(int fd) { + struct statfs s; + + if (fstatfs(fd, &s) < 0) + return -errno; + + return is_temporary_fs(&s); +} + int rm_rf_children(int fd, bool only_dirs, bool honour_sticky, struct stat *root_dev) { struct statfs s; @@ -2871,6 +3060,19 @@ int rm_rf_children(int fd, bool only_dirs, bool honour_sticky, struct stat *root return rm_rf_children_dangerous(fd, only_dirs, honour_sticky, root_dev); } +static int file_is_priv_sticky(const char *p) { + struct stat st; + + assert(p); + + if (lstat(p, &st) < 0) + return -errno; + + return + (st.st_uid == 0 || st.st_uid == getuid()) && + (st.st_mode & S_ISVTX); +} + static int rm_rf_internal(const char *path, bool only_dirs, bool delete_root, bool honour_sticky, bool dangerous) { int fd, r; struct statfs s; @@ -2888,7 +3090,7 @@ static int rm_rf_internal(const char *path, bool only_dirs, bool delete_root, bo fd = open(path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME); if (fd < 0) { - if (errno != ENOTDIR) + if (errno != ENOTDIR && errno != ELOOP) return -errno; if (!dangerous) { @@ -2951,11 +3153,11 @@ int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid) { * first change the access mode and only then hand out * ownership to avoid a window where access is too open. */ - if (mode != (mode_t) -1) + if (mode != MODE_INVALID) if (chmod(path, mode) < 0) return -errno; - if (uid != (uid_t) -1 || gid != (gid_t) -1) + if (uid != UID_INVALID || gid != GID_INVALID) if (chown(path, uid, gid) < 0) return -errno; @@ -2969,11 +3171,11 @@ int fchmod_and_fchown(int fd, mode_t mode, uid_t uid, gid_t gid) { * first change the access mode and only then hand out * ownership to avoid a window where access is too open. */ - if (mode != (mode_t) -1) + if (mode != MODE_INVALID) if (fchmod(fd, mode) < 0) return -errno; - if (uid != (uid_t) -1 || gid != (gid_t) -1) + if (uid != UID_INVALID || gid != GID_INVALID) if (fchown(fd, uid, gid) < 0) return -errno; @@ -3043,7 +3245,7 @@ int status_vprintf(const char *status, bool ellipse, bool ephemeral, const char if (emax < 3) emax = 3; - e = ellipsize(s, emax, 75); + e = ellipsize(s, emax, 50); if (e) { free(s); s = e; @@ -3109,7 +3311,8 @@ char *replace_env(const char *format, char **env) { case CURLY: if (*e == '{') { - if (!(k = strnappend(r, word, e-word-1))) + k = strnappend(r, word, e-word-1); + if (!k) goto fail; free(r); @@ -3119,7 +3322,8 @@ char *replace_env(const char *format, char **env) { state = VARIABLE; } else if (*e == '$') { - if (!(k = strnappend(r, word, e-word))) + k = strnappend(r, word, e-word); + if (!k) goto fail; free(r); @@ -3151,7 +3355,8 @@ char *replace_env(const char *format, char **env) { } } - if (!(k = strnappend(r, word, e-word))) + k = strnappend(r, word, e-word); + if (!k) goto fail; free(r); @@ -3163,12 +3368,13 @@ fail: } char **replace_env_argv(char **argv, char **env) { - char **r, **i; + char **ret, **i; unsigned k = 0, l = 0; l = strv_length(argv); - if (!(r = new(char*, l+1))) + ret = new(char*, l+1); + if (!ret) return NULL; STRV_FOREACH(i, argv) { @@ -3181,10 +3387,12 @@ char **replace_env_argv(char **argv, char **env) { e = strv_env_get(env, *i+1); if (e) { + int r; - if (!(m = strv_split_quoted(e))) { - r[k] = NULL; - strv_free(r); + r = strv_split_quoted(&m, e, true); + if (r < 0) { + ret[k] = NULL; + strv_free(ret); return NULL; } } else @@ -3193,16 +3401,17 @@ char **replace_env_argv(char **argv, char **env) { q = strv_length(m); l = l + q - 1; - if (!(w = realloc(r, sizeof(char*) * (l+1)))) { - r[k] = NULL; - strv_free(r); + w = realloc(ret, sizeof(char*) * (l+1)); + if (!w) { + ret[k] = NULL; + strv_free(ret); strv_free(m); return NULL; } - r = w; + ret = w; if (m) { - memcpy(r + k, m, q * sizeof(char*)); + memcpy(ret + k, m, q * sizeof(char*)); free(m); } @@ -3211,14 +3420,16 @@ char **replace_env_argv(char **argv, char **env) { } /* If ${FOO} appears as part of a word, replace it by the variable as-is */ - if (!(r[k++] = replace_env(*i, env))) { - strv_free(r); + ret[k] = replace_env(*i, env); + if (!ret[k]) { + strv_free(ret); return NULL; } + k++; } - r[k] = NULL; - return r; + ret[k] = NULL; + return ret; } int fd_columns(int fd) { @@ -3243,7 +3454,7 @@ unsigned columns(void) { c = 0; e = getenv("COLUMNS"); if (e) - safe_atoi(e, &c); + (void) safe_atoi(e, &c); if (c <= 0) c = fd_columns(STDOUT_FILENO); @@ -3252,7 +3463,7 @@ unsigned columns(void) { c = 80; cached_columns = c; - return c; + return cached_columns; } int fd_lines(int fd) { @@ -3269,7 +3480,7 @@ int fd_lines(int fd) { unsigned lines(void) { const char *e; - unsigned l; + int l; if (_likely_(cached_lines > 0)) return cached_lines; @@ -3277,7 +3488,7 @@ unsigned lines(void) { l = 0; e = getenv("LINES"); if (e) - safe_atou(e, &l); + (void) safe_atoi(e, &l); if (l <= 0) l = fd_lines(STDOUT_FILENO); @@ -3455,7 +3666,7 @@ int touch_file(const char *path, bool parents, usec_t stamp, uid_t uid, gid_t gi return -errno; } - if (uid != (uid_t) -1 || gid != (gid_t) -1) { + if (uid != UID_INVALID || gid != GID_INVALID) { r = fchown(fd, uid, gid); if (r < 0) return -errno; @@ -3476,7 +3687,7 @@ int touch_file(const char *path, bool parents, usec_t stamp, uid_t uid, gid_t gi } int touch(const char *path) { - return touch_file(path, false, USEC_INFINITY, (uid_t) -1, (gid_t) -1, 0); + return touch_file(path, false, USEC_INFINITY, UID_INVALID, GID_INVALID, 0); } char *unquote(const char *s, const char* quotes) { @@ -3486,7 +3697,7 @@ char *unquote(const char *s, const char* quotes) { /* This is rather stupid, simply removes the heading and * trailing quotes if there is one. Doesn't care about * escaping or anything. We should make this smarter one - * day...*/ + * day... */ l = strlen(s); if (l < 2) @@ -3499,41 +3710,33 @@ char *unquote(const char *s, const char* quotes) { } char *normalize_env_assignment(const char *s) { - _cleanup_free_ char *name = NULL, *value = NULL, *p = NULL; - char *eq, *r; + _cleanup_free_ char *value = NULL; + const char *eq; + char *p, *name; eq = strchr(s, '='); if (!eq) { - char *t; + char *r, *t; r = strdup(s); if (!r) return NULL; t = strstrip(r); - if (t == r) - return r; + if (t != r) + memmove(r, t, strlen(t) + 1); - memmove(r, t, strlen(t) + 1); return r; } - name = strndup(s, eq - s); - if (!name) - return NULL; - - p = strdup(eq + 1); - if (!p) - return NULL; + name = strndupa(s, eq - s); + p = strdupa(eq + 1); value = unquote(strstrip(p), QUOTES); if (!value) return NULL; - if (asprintf(&r, "%s=%s", strstrip(name), value) < 0) - r = NULL; - - return r; + return strjoin(strstrip(name), "=", value, NULL); } int wait_for_terminate(pid_t pid, siginfo_t *status) { @@ -3569,8 +3772,11 @@ int wait_for_terminate(pid_t pid, siginfo_t *status) { * * That is, success is indicated by a return value of zero, and an * error is indicated by a non-zero value. + * + * A warning is emitted if the process terminates abnormally, + * and also if it returns non-zero unless check_exit_code is true. */ -int wait_for_terminate_and_warn(const char *name, pid_t pid) { +int wait_for_terminate_and_warn(const char *name, pid_t pid, bool check_exit_code) { int r; siginfo_t status; @@ -3578,20 +3784,17 @@ int wait_for_terminate_and_warn(const char *name, pid_t pid) { assert(pid > 1); r = wait_for_terminate(pid, &status); - if (r < 0) { - log_warning("Failed to wait for %s: %s", name, strerror(-r)); - return r; - } + if (r < 0) + return log_warning_errno(r, "Failed to wait for %s: %m", name); if (status.si_code == CLD_EXITED) { - if (status.si_status != 0) { - log_warning("%s failed with error code %i.", name, status.si_status); - return status.si_status; - } - - log_debug("%s succeeded.", name); - return 0; + if (status.si_status != 0) + log_full(check_exit_code ? LOG_WARNING : LOG_DEBUG, + "%s failed with error code %i.", name, status.si_status); + else + log_debug("%s succeeded.", name); + return status.si_status; } else if (status.si_code == CLD_KILLED || status.si_code == CLD_DUMPED) { @@ -3808,13 +4011,13 @@ bool tty_is_vc_resolve(const char *tty) { const char *default_term_for_tty(const char *tty) { assert(tty); - return tty_is_vc_resolve(tty) ? "TERM=linux" : "TERM=vt102"; + return tty_is_vc_resolve(tty) ? "TERM=linux" : "TERM=vt220"; } bool dirent_is_file(const struct dirent *de) { assert(de); - if (ignore_file(de->d_name)) + if (hidden_file(de->d_name)) return false; if (de->d_type != DT_REG && @@ -3833,76 +4036,75 @@ bool dirent_is_file_with_suffix(const struct dirent *de, const char *suffix) { de->d_type != DT_UNKNOWN) return false; - if (ignore_file_allow_backup(de->d_name)) + if (hidden_file_allow_backup(de->d_name)) return false; return endswith(de->d_name, suffix); } -void execute_directory(const char *directory, DIR *d, usec_t timeout, char *argv[]) { - pid_t executor_pid; - int r; - - assert(directory); +static int do_execute(char **directories, usec_t timeout, char *argv[]) { + _cleanup_hashmap_free_free_ Hashmap *pids = NULL; + _cleanup_set_free_free_ Set *seen = NULL; + char **directory; - /* Executes all binaries in a directory in parallel and waits - * for them to finish. Optionally a timeout is applied. */ + /* We fork this all off from a child process so that we can + * somewhat cleanly make use of SIGALRM to set a time limit */ - executor_pid = fork(); - if (executor_pid < 0) { - log_error("Failed to fork: %m"); - return; - - } else if (executor_pid == 0) { - _cleanup_hashmap_free_free_ Hashmap *pids = NULL; - _cleanup_closedir_ DIR *_d = NULL; - struct dirent *de; - sigset_t ss; + reset_all_signal_handlers(); + reset_signal_mask(); - /* We fork this all off from a child process so that - * we can somewhat cleanly make use of SIGALRM to set - * a time limit */ + assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0); - reset_all_signal_handlers(); + pids = hashmap_new(NULL); + if (!pids) + return log_oom(); - assert_se(sigemptyset(&ss) == 0); - assert_se(sigprocmask(SIG_SETMASK, &ss, NULL) == 0); + seen = set_new(&string_hash_ops); + if (!seen) + return log_oom(); - assert_se(prctl(PR_SET_PDEATHSIG, SIGTERM) == 0); + STRV_FOREACH(directory, directories) { + _cleanup_closedir_ DIR *d; + struct dirent *de; + d = opendir(*directory); if (!d) { - d = _d = opendir(directory); - if (!d) { - if (errno == ENOENT) - _exit(EXIT_SUCCESS); - - log_error("Failed to enumerate directory %s: %m", directory); - _exit(EXIT_FAILURE); - } - } + if (errno == ENOENT) + continue; - pids = hashmap_new(NULL, NULL); - if (!pids) { - log_oom(); - _exit(EXIT_FAILURE); + return log_error_errno(errno, "Failed to open directory %s: %m", *directory); } FOREACH_DIRENT(de, d, break) { _cleanup_free_ char *path = NULL; pid_t pid; + int r; if (!dirent_is_file(de)) continue; - path = strjoin(directory, "/", de->d_name, NULL); - if (!path) { - log_oom(); - _exit(EXIT_FAILURE); + if (set_contains(seen, de->d_name)) { + log_debug("%1$s/%2$s skipped (%2$s was already seen).", *directory, de->d_name); + continue; } + r = set_put_strdup(seen, de->d_name); + if (r < 0) + return log_oom(); + + path = strjoin(*directory, "/", de->d_name, NULL); + if (!path) + return log_oom(); + + if (null_or_empty_path(path)) { + log_debug("%s is empty (a mask).", path); + continue; + } else + log_debug("%s will be executed.", path); + pid = fork(); if (pid < 0) { - log_error("Failed to fork: %m"); + log_error_errno(errno, "Failed to fork: %m"); continue; } else if (pid == 0) { char *_argv[2]; @@ -3917,46 +4119,68 @@ void execute_directory(const char *directory, DIR *d, usec_t timeout, char *argv argv[0] = path; execv(path, argv); - log_error("Failed to execute %s: %m", path); - _exit(EXIT_FAILURE); + return log_error_errno(errno, "Failed to execute %s: %m", path); } - log_debug("Spawned %s as " PID_FMT ".", path, pid); r = hashmap_put(pids, UINT_TO_PTR(pid), path); - if (r < 0) { - log_oom(); - _exit(EXIT_FAILURE); - } - + if (r < 0) + return log_oom(); path = NULL; } + } - /* Abort execution of this process after the - * timout. We simply rely on SIGALRM as default action - * terminating the process, and turn on alarm(). */ + /* Abort execution of this process after the timout. We simply + * rely on SIGALRM as default action terminating the process, + * and turn on alarm(). */ - if (timeout != USEC_INFINITY) - alarm((timeout + USEC_PER_SEC - 1) / USEC_PER_SEC); + if (timeout != USEC_INFINITY) + alarm((timeout + USEC_PER_SEC - 1) / USEC_PER_SEC); - while (!hashmap_isempty(pids)) { - _cleanup_free_ char *path = NULL; - pid_t pid; + while (!hashmap_isempty(pids)) { + _cleanup_free_ char *path = NULL; + pid_t pid; - pid = PTR_TO_UINT(hashmap_first_key(pids)); - assert(pid > 0); + pid = PTR_TO_UINT(hashmap_first_key(pids)); + assert(pid > 0); - path = hashmap_remove(pids, UINT_TO_PTR(pid)); - assert(path); + path = hashmap_remove(pids, UINT_TO_PTR(pid)); + assert(path); - wait_for_terminate_and_warn(path, pid); - } + wait_for_terminate_and_warn(path, pid, true); + } - _exit(EXIT_SUCCESS); + return 0; +} + +void execute_directories(const char* const* directories, usec_t timeout, char *argv[]) { + pid_t executor_pid; + int r; + char *name; + char **dirs = (char**) directories; + + assert(!strv_isempty(dirs)); + + name = basename(dirs[0]); + assert(!isempty(name)); + + /* Executes all binaries in the directories in parallel and waits + * for them to finish. Optionally a timeout is applied. If a file + * with the same name exists in more than one directory, the + * earliest one wins. */ + + executor_pid = fork(); + if (executor_pid < 0) { + log_error_errno(errno, "Failed to fork: %m"); + return; + + } else if (executor_pid == 0) { + r = do_execute(dirs, timeout, argv); + _exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS); } - wait_for_terminate_and_warn(directory, executor_pid); + wait_for_terminate_and_warn(name, executor_pid, true); } int kill_and_sigcont(pid_t pid, int sig) { @@ -4079,6 +4303,23 @@ bool machine_name_is_valid(const char *s) { return true; } +bool image_name_is_valid(const char *s) { + if (!filename_is_valid(s)) + return false; + + if (string_has_cc(s, NULL)) + return false; + + if (!utf8_is_valid(s)) + return false; + + /* Temporary files for atomically creating new files */ + if (startswith(s, ".#")) + return false; + + return true; +} + int pipe_eof(int fd) { struct pollfd pollfd = { .fd = fd, @@ -4120,15 +4361,15 @@ int fd_wait_for_event(int fd, int event, usec_t t) { int fopen_temporary(const char *path, FILE **_f, char **_temp_path) { FILE *f; char *t; - int fd; + int r, fd; assert(path); assert(_f); assert(_temp_path); - t = tempfn_xxxxxx(path); - if (!t) - return -ENOMEM; + r = tempfn_xxxxxx(path, &t); + if (r < 0) + return r; fd = mkostemp_safe(t, O_WRONLY|O_CLOEXEC); if (fd < 0) { @@ -4239,13 +4480,14 @@ int vt_disallocate(const char *name) { int symlink_atomic(const char *from, const char *to) { _cleanup_free_ char *t = NULL; + int r; assert(from); assert(to); - t = tempfn_random(to); - if (!t) - return -ENOMEM; + r = tempfn_random(to, &t); + if (r < 0) + return r; if (symlink(from, t) < 0) return -errno; @@ -4260,12 +4502,13 @@ int symlink_atomic(const char *from, const char *to) { int mknod_atomic(const char *path, mode_t mode, dev_t dev) { _cleanup_free_ char *t = NULL; + int r; assert(path); - t = tempfn_random(path); - if (!t) - return -ENOMEM; + r = tempfn_random(path, &t); + if (r < 0) + return r; if (mknod(t, mode, dev) < 0) return -errno; @@ -4280,12 +4523,13 @@ int mknod_atomic(const char *path, mode_t mode, dev_t dev) { int mkfifo_atomic(const char *path, mode_t mode) { _cleanup_free_ char *t = NULL; + int r; assert(path); - t = tempfn_random(path); - if (!t) - return -ENOMEM; + r = tempfn_random(path, &t); + if (r < 0) + return r; if (mkfifo(t, mode) < 0) return -errno; @@ -4754,19 +4998,6 @@ int block_get_whole_disk(dev_t d, dev_t *ret) { return -ENOENT; } -int file_is_priv_sticky(const char *p) { - struct stat st; - - assert(p); - - if (lstat(p, &st) < 0) - return -errno; - - return - (st.st_uid == 0 || st.st_uid == getuid()) && - (st.st_mode & S_ISVTX); -} - static const char *const ioprio_class_table[] = { [IOPRIO_CLASS_NONE] = "none", [IOPRIO_CLASS_RT] = "realtime", @@ -4937,7 +5168,7 @@ int signal_from_string(const char *s) { if (signo > 0 && signo < _NSIG) return signo; } - return -1; + return -EINVAL; } bool kexec_loaded(void) { @@ -4952,24 +5183,6 @@ bool kexec_loaded(void) { return loaded; } -int strdup_or_null(const char *a, char **b) { - char *c; - - assert(b); - - if (!a) { - *b = NULL; - return 0; - } - - c = strdup(a); - if (!c) - return -ENOMEM; - - *b = c; - return 0; -} - int prot_from_flags(int flags) { switch (flags & O_ACCMODE) { @@ -5003,6 +5216,9 @@ char *format_bytes(char *buf, size_t l, off_t t) { { "K", 1024ULL }, }; + if (t == (off_t) -1) + return NULL; + for (i = 0; i < ELEMENTSOF(table); i++) { if (t >= table[i].factor) { @@ -5073,9 +5289,9 @@ int fd_inc_rcvbuf(int fd, size_t n) { } int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *path, ...) { - pid_t parent_pid, agent_pid; - int fd; bool stdout_is_tty, stderr_is_tty; + pid_t parent_pid, agent_pid; + sigset_t ss, saved_ss; unsigned n, i; va_list ap; char **l; @@ -5083,16 +5299,25 @@ int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *pa assert(pid); assert(path); - parent_pid = getpid(); - /* Spawns a temporary TTY agent, making sure it goes away when * we go away */ - agent_pid = fork(); - if (agent_pid < 0) - return -errno; + parent_pid = getpid(); + + /* First we temporarily block all signals, so that the new + * child has them blocked initially. This way, we can be sure + * that SIGTERMs are not lost we might send to the agent. */ + assert_se(sigfillset(&ss) >= 0); + assert_se(sigprocmask(SIG_SETMASK, &ss, &saved_ss) >= 0); + + agent_pid = fork(); + if (agent_pid < 0) { + assert_se(sigprocmask(SIG_SETMASK, &saved_ss, NULL) >= 0); + return -errno; + } if (agent_pid != 0) { + assert_se(sigprocmask(SIG_SETMASK, &saved_ss, NULL) >= 0); *pid = agent_pid; return 0; } @@ -5103,8 +5328,14 @@ int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *pa if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0) _exit(EXIT_FAILURE); + /* Make sure we actually can kill the agent, if we need to, in + * case somebody invoked us from a shell script that trapped + * SIGTERM or so... */ + reset_all_signal_handlers(); + reset_signal_mask(); + /* Check whether our parent died before we were able - * to set the death signal */ + * to set the death signal and unblock the signals */ if (getppid() != parent_pid) _exit(EXIT_SUCCESS); @@ -5115,6 +5346,8 @@ int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *pa stderr_is_tty = isatty(STDERR_FILENO); if (!stdout_is_tty || !stderr_is_tty) { + int fd; + /* Detach from stdout/stderr. and reopen * /dev/tty for them. This is important to * ensure that when systemctl is started via @@ -5124,7 +5357,7 @@ int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *pa * keep an unused copy of stdin around. */ fd = open("/dev/tty", O_WRONLY); if (fd < 0) { - log_error("Failed to open /dev/tty: %m"); + log_error_errno(errno, "Failed to open /dev/tty: %m"); _exit(EXIT_FAILURE); } @@ -5307,16 +5540,12 @@ int make_console_stdio(void) { /* Make /dev/console the controlling terminal and stdin/stdout/stderr */ fd = acquire_terminal("/dev/console", false, true, true, USEC_INFINITY); - if (fd < 0) { - log_error("Failed to acquire terminal: %s", strerror(-fd)); - return fd; - } + if (fd < 0) + return log_error_errno(fd, "Failed to acquire terminal: %m"); r = make_stdio(fd); - if (r < 0) { - log_error("Failed to duplicate terminal fd: %s", strerror(-r)); - return r; - } + if (r < 0) + return log_error_errno(r, "Failed to duplicate terminal fd: %m"); return 0; } @@ -5415,7 +5644,7 @@ int get_shell(char **_s) { return 0; } -bool filename_is_safe(const char *p) { +bool filename_is_valid(const char *p) { if (isempty(p)) return false; @@ -5746,7 +5975,7 @@ int on_ac_power(void) { if (!de) break; - if (ignore_file(de->d_name)) + if (hidden_file(de->d_name)) continue; device = openat(dirfd(d), de->d_name, O_DIRECTORY|O_RDONLY|O_CLOEXEC|O_NOCTTY); @@ -6071,85 +6300,48 @@ int split_pair(const char *s, const char *sep, char **l, char **r) { } int shall_restore_state(void) { - _cleanup_free_ char *line = NULL; - const char *word, *state; - size_t l; + _cleanup_free_ char *value = NULL; int r; - r = proc_cmdline(&line); + r = get_proc_cmdline_key("systemd.restore_state=", &value); if (r < 0) return r; - if (r == 0) /* Container ... */ - return 1; - - r = 1; - - FOREACH_WORD_QUOTED(word, l, line, state) { - const char *e; - char n[l+1]; - int k; - - memcpy(n, word, l); - n[l] = 0; - - e = startswith(n, "systemd.restore_state="); - if (!e) - continue; - - k = parse_boolean(e); - if (k >= 0) - r = k; - } + if (r == 0) + return true; - return r; + return parse_boolean(value) != 0; } int proc_cmdline(char **ret) { - int r; - - if (detect_container(NULL) > 0) { - char *buf = NULL, *p; - size_t sz = 0; - - r = read_full_file("/proc/1/cmdline", &buf, &sz); - if (r < 0) - return r; - - for (p = buf; p + 1 < buf + sz; p++) - if (*p == 0) - *p = ' '; - - *p = 0; - *ret = buf; - return 1; - } - - r = read_one_line_file("/proc/cmdline", ret); - if (r < 0) - return r; + assert(ret); - return 1; + if (detect_container(NULL) > 0) + return get_process_cmdline(1, 0, false, ret); + else + return read_one_line_file("/proc/cmdline", ret); } int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value)) { _cleanup_free_ char *line = NULL; - const char *w, *state; - size_t l; + const char *p; int r; assert(parse_item); r = proc_cmdline(&line); if (r < 0) - log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r)); - if (r <= 0) - return 0; + return r; - FOREACH_WORD_QUOTED(w, l, line, state) { - char word[l+1], *value; + p = line; + for (;;) { + _cleanup_free_ char *word = NULL; + char *value = NULL; - memcpy(word, w, l); - word[l] = 0; + r = unquote_first_word(&p, &word, true); + if (r < 0) + return r; + if (r == 0) + break; /* Filter out arguments that are intended only for the * initrd */ @@ -6168,6 +6360,59 @@ int parse_proc_cmdline(int (*parse_item)(const char *key, const char *value)) { return 0; } +int get_proc_cmdline_key(const char *key, char **value) { + _cleanup_free_ char *line = NULL, *ret = NULL; + bool found = false; + const char *p; + int r; + + assert(key); + + r = proc_cmdline(&line); + if (r < 0) + return r; + + p = line; + for (;;) { + _cleanup_free_ char *word = NULL; + const char *e; + + r = unquote_first_word(&p, &word, true); + if (r < 0) + return r; + if (r == 0) + break; + + /* Filter out arguments that are intended only for the + * initrd */ + if (!in_initrd() && startswith(word, "rd.")) + continue; + + if (value) { + e = startswith(word, key); + if (!e) + continue; + + r = free_and_strdup(&ret, e); + if (r < 0) + return r; + + found = true; + } else { + if (streq(word, key)) + found = true; + } + } + + if (value) { + *value = ret; + ret = NULL; + } + + return found; + +} + int container_get_leader(const char *machine, pid_t *pid) { _cleanup_free_ char *s = NULL, *class = NULL; const char *p; @@ -6338,6 +6583,10 @@ int getpeercred(int fd, struct ucred *ucred) { * to namespacing issues */ if (u.pid <= 0) return -ENODATA; + if (u.uid == UID_INVALID) + return -ENODATA; + if (u.gid == GID_INVALID) + return -ENODATA; *ucred = u; return 0; @@ -6500,23 +6749,6 @@ uint64_t physical_memory(void) { return (uint64_t) mem * (uint64_t) page_size(); } -char* mount_test_option(const char *haystack, const char *needle) { - - struct mntent me = { - .mnt_opts = (char*) haystack - }; - - assert(needle); - - /* Like glibc's hasmntopt(), but works on a string, not a - * struct mntent */ - - if (!haystack) - return NULL; - - return hasmntopt(&me, needle); -} - void hexdump(FILE *f, const void *p, size_t s) { const uint8_t *b = p; unsigned n = 0; @@ -6641,6 +6873,15 @@ int umount_recursive(const char *prefix, int flags) { return r ? r : n; } +static int get_mount_flags(const char *path, unsigned long *flags) { + struct statvfs buf; + + if (statvfs(path, &buf) < 0) + return -errno; + *flags = buf.f_flag; + return 0; +} + int bind_remount_recursive(const char *prefix, bool ro) { _cleanup_set_free_free_ Set *done = NULL; _cleanup_free_ char *cleaned = NULL; @@ -6666,7 +6907,7 @@ int bind_remount_recursive(const char *prefix, bool ro) { path_kill_slashes(cleaned); - done = set_new(string_hash_func, string_compare_func); + done = set_new(&string_hash_ops); if (!done) return -ENOMEM; @@ -6675,8 +6916,9 @@ int bind_remount_recursive(const char *prefix, bool ro) { _cleanup_set_free_free_ Set *todo = NULL; bool top_autofs = false; char *x; + unsigned long orig_flags; - todo = set_new(string_hash_func, string_compare_func); + todo = set_new(&string_hash_ops); if (!todo) return -ENOMEM; @@ -6752,7 +6994,11 @@ int bind_remount_recursive(const char *prefix, bool ro) { if (mount(cleaned, cleaned, NULL, MS_BIND|MS_REC, NULL) < 0) return -errno; - if (mount(NULL, prefix, NULL, MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) + orig_flags = 0; + (void) get_mount_flags(cleaned, &orig_flags); + orig_flags &= ~MS_RDONLY; + + if (mount(NULL, prefix, NULL, orig_flags|MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) return -errno; x = strdup(cleaned); @@ -6772,7 +7018,14 @@ int bind_remount_recursive(const char *prefix, bool ro) { if (r < 0) return r; - if (mount(NULL, x, NULL, MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) { + /* Try to reuse the original flag set, but + * don't care for errors, in case of + * obstructed mounts */ + orig_flags = 0; + (void) get_mount_flags(x, &orig_flags); + orig_flags &= ~MS_RDONLY; + + if (mount(NULL, x, NULL, orig_flags|MS_BIND|MS_REMOUNT|(ro ? MS_RDONLY : 0), NULL) < 0) { /* Deal with mount points that are * obstructed by a later mount */ @@ -6797,42 +7050,61 @@ int fflush_and_check(FILE *f) { return 0; } -char *tempfn_xxxxxx(const char *p) { +int tempfn_xxxxxx(const char *p, char **ret) { const char *fn; char *t; - size_t k; assert(p); + assert(ret); - t = new(char, strlen(p) + 1 + 6 + 1); - if (!t) - return NULL; + /* + * Turns this: + * /foo/bar/waldo + * + * Into this: + * /foo/bar/.#waldoXXXXXX + */ fn = basename(p); - k = fn - p; + if (!filename_is_valid(fn)) + return -EINVAL; + + t = new(char, strlen(p) + 2 + 6 + 1); + if (!t) + return -ENOMEM; - strcpy(stpcpy(stpcpy(mempcpy(t, p, k), "."), fn), "XXXXXX"); + strcpy(stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn), "XXXXXX"); - return t; + *ret = path_kill_slashes(t); + return 0; } -char *tempfn_random(const char *p) { +int tempfn_random(const char *p, char **ret) { const char *fn; char *t, *x; uint64_t u; - size_t k; unsigned i; assert(p); + assert(ret); - t = new(char, strlen(p) + 1 + 16 + 1); - if (!t) - return NULL; + /* + * Turns this: + * /foo/bar/waldo + * + * Into this: + * /foo/bar/.#waldobaa2a261115984a9 + */ fn = basename(p); - k = fn - p; + if (!filename_is_valid(fn)) + return -EINVAL; + + t = new(char, strlen(p) + 2 + 16 + 1); + if (!t) + return -ENOMEM; - x = stpcpy(stpcpy(mempcpy(t, p, k), "."), fn); + x = stpcpy(stpcpy(mempcpy(t, p, fn - p), ".#"), fn); u = random_u64(); for (i = 0; i < 16; i++) { @@ -6842,18 +7114,53 @@ char *tempfn_random(const char *p) { *x = 0; - return t; + *ret = path_kill_slashes(t); + return 0; +} + +int tempfn_random_child(const char *p, char **ret) { + char *t, *x; + uint64_t u; + unsigned i; + + assert(p); + assert(ret); + + /* Turns this: + * /foo/bar/waldo + * Into this: + * /foo/bar/waldo/.#3c2b6219aa75d7d0 + */ + + t = new(char, strlen(p) + 3 + 16 + 1); + if (!t) + return -ENOMEM; + + x = stpcpy(stpcpy(t, p), "/.#"); + + u = random_u64(); + for (i = 0; i < 16; i++) { + *(x++) = hexchar(u & 0xF); + u >>= 4; + } + + *x = 0; + + *ret = path_kill_slashes(t); + return 0; } /* make sure the hostname is not "localhost" */ bool is_localhost(const char *hostname) { assert(hostname); - /* This tries to identify local hostnames described in RFC6761 - * plus the redhatism of .localdomain */ + /* This tries to identify local host and domain names + * described in RFC6761 plus the redhatism of .localdomain */ return streq(hostname, "localhost") || streq(hostname, "localhost.") || + streq(hostname, "localdomain.") || + streq(hostname, "localdomain") || endswith(hostname, ".localhost") || endswith(hostname, ".localhost.") || endswith(hostname, ".localdomain") || @@ -6899,3 +7206,594 @@ int take_password_lock(const char *root) { return fd; } + +int is_symlink(const char *path) { + struct stat info; + + if (lstat(path, &info) < 0) + return -errno; + + return !!S_ISLNK(info.st_mode); +} + +int is_dir(const char* path, bool follow) { + struct stat st; + int r; + + if (follow) + r = stat(path, &st); + else + r = lstat(path, &st); + if (r < 0) + return -errno; + + return !!S_ISDIR(st.st_mode); +} + +int unquote_first_word(const char **p, char **ret, bool relax) { + _cleanup_free_ char *s = NULL; + size_t allocated = 0, sz = 0; + + enum { + START, + VALUE, + VALUE_ESCAPE, + SINGLE_QUOTE, + SINGLE_QUOTE_ESCAPE, + DOUBLE_QUOTE, + DOUBLE_QUOTE_ESCAPE, + SPACE, + } state = START; + + assert(p); + assert(*p); + assert(ret); + + /* Parses the first word of a string, and returns it in + * *ret. Removes all quotes in the process. When parsing fails + * (because of an uneven number of quotes or similar), leaves + * the pointer *p at the first invalid character. */ + + for (;;) { + char c = **p; + + switch (state) { + + case START: + if (c == 0) + goto finish; + else if (strchr(WHITESPACE, c)) + break; + + state = VALUE; + /* fallthrough */ + + case VALUE: + if (c == 0) + goto finish; + else if (c == '\'') + state = SINGLE_QUOTE; + else if (c == '\\') + state = VALUE_ESCAPE; + else if (c == '\"') + state = DOUBLE_QUOTE; + else if (strchr(WHITESPACE, c)) + state = SPACE; + else { + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + } + + break; + + case VALUE_ESCAPE: + if (c == 0) { + if (relax) + goto finish; + return -EINVAL; + } + + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + state = VALUE; + + break; + + case SINGLE_QUOTE: + if (c == 0) { + if (relax) + goto finish; + return -EINVAL; + } else if (c == '\'') + state = VALUE; + else if (c == '\\') + state = SINGLE_QUOTE_ESCAPE; + else { + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + } + + break; + + case SINGLE_QUOTE_ESCAPE: + if (c == 0) { + if (relax) + goto finish; + return -EINVAL; + } + + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + state = SINGLE_QUOTE; + break; + + case DOUBLE_QUOTE: + if (c == 0) + return -EINVAL; + else if (c == '\"') + state = VALUE; + else if (c == '\\') + state = DOUBLE_QUOTE_ESCAPE; + else { + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + } + + break; + + case DOUBLE_QUOTE_ESCAPE: + if (c == 0) { + if (relax) + goto finish; + return -EINVAL; + } + + if (!GREEDY_REALLOC(s, allocated, sz+2)) + return -ENOMEM; + + s[sz++] = c; + state = DOUBLE_QUOTE; + break; + + case SPACE: + if (c == 0) + goto finish; + if (!strchr(WHITESPACE, c)) + goto finish; + + break; + } + + (*p) ++; + } + +finish: + if (!s) { + *ret = NULL; + return 0; + } + + s[sz] = 0; + *ret = s; + s = NULL; + + return 1; +} + +int unquote_many_words(const char **p, ...) { + va_list ap; + char **l; + int n = 0, i, c, r; + + /* Parses a number of words from a string, stripping any + * quotes if necessary. */ + + assert(p); + + /* Count how many words are expected */ + va_start(ap, p); + for (;;) { + if (!va_arg(ap, char **)) + break; + n++; + } + va_end(ap); + + if (n <= 0) + return 0; + + /* Read all words into a temporary array */ + l = newa0(char*, n); + for (c = 0; c < n; c++) { + + r = unquote_first_word(p, &l[c], false); + if (r < 0) { + int j; + + for (j = 0; j < c; j++) + free(l[j]); + + return r; + } + + if (r == 0) + break; + } + + /* If we managed to parse all words, return them in the passed + * in parameters */ + va_start(ap, p); + for (i = 0; i < n; i++) { + char **v; + + v = va_arg(ap, char **); + assert(v); + + *v = l[i]; + } + va_end(ap); + + return c; +} + +int free_and_strdup(char **p, const char *s) { + char *t; + + assert(p); + + /* Replaces a string pointer with an strdup()ed new string, + * possibly freeing the old one. */ + + if (s) { + t = strdup(s); + if (!t) + return -ENOMEM; + } else + t = NULL; + + free(*p); + *p = t; + + return 0; +} + +int sethostname_idempotent(const char *s) { + int r; + char buf[HOST_NAME_MAX + 1] = {}; + + assert(s); + + r = gethostname(buf, sizeof(buf)); + if (r < 0) + return -errno; + + if (streq(buf, s)) + return 0; + + r = sethostname(s, strlen(s)); + if (r < 0) + return -errno; + + return 1; +} + +int ptsname_malloc(int fd, char **ret) { + size_t l = 100; + + assert(fd >= 0); + assert(ret); + + for (;;) { + char *c; + + c = new(char, l); + if (!c) + return -ENOMEM; + + if (ptsname_r(fd, c, l) == 0) { + *ret = c; + return 0; + } + if (errno != ERANGE) { + free(c); + return -errno; + } + + free(c); + l *= 2; + } +} + +int openpt_in_namespace(pid_t pid, int flags) { + _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, rootfd = -1; + _cleanup_close_pair_ int pair[2] = { -1, -1 }; + union { + struct cmsghdr cmsghdr; + uint8_t buf[CMSG_SPACE(sizeof(int))]; + } control = {}; + struct msghdr mh = { + .msg_control = &control, + .msg_controllen = sizeof(control), + }; + struct cmsghdr *cmsg; + siginfo_t si; + pid_t child; + int r; + + assert(pid > 0); + + r = namespace_open(pid, &pidnsfd, &mntnsfd, NULL, &rootfd); + if (r < 0) + return r; + + if (socketpair(AF_UNIX, SOCK_DGRAM, 0, pair) < 0) + return -errno; + + child = fork(); + if (child < 0) + return -errno; + + if (child == 0) { + int master; + + pair[0] = safe_close(pair[0]); + + r = namespace_enter(pidnsfd, mntnsfd, -1, rootfd); + if (r < 0) + _exit(EXIT_FAILURE); + + master = posix_openpt(flags); + if (master < 0) + _exit(EXIT_FAILURE); + + cmsg = CMSG_FIRSTHDR(&mh); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + cmsg->cmsg_len = CMSG_LEN(sizeof(int)); + memcpy(CMSG_DATA(cmsg), &master, sizeof(int)); + + mh.msg_controllen = cmsg->cmsg_len; + + if (sendmsg(pair[1], &mh, MSG_NOSIGNAL) < 0) + _exit(EXIT_FAILURE); + + _exit(EXIT_SUCCESS); + } + + pair[1] = safe_close(pair[1]); + + r = wait_for_terminate(child, &si); + if (r < 0) + return r; + if (si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS) + return -EIO; + + if (recvmsg(pair[0], &mh, MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) < 0) + return -errno; + + for (cmsg = CMSG_FIRSTHDR(&mh); cmsg; cmsg = CMSG_NXTHDR(&mh, cmsg)) + if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) { + int *fds; + unsigned n_fds; + + fds = (int*) CMSG_DATA(cmsg); + n_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int); + + if (n_fds != 1) { + close_many(fds, n_fds); + return -EIO; + } + + return fds[0]; + } + + return -EIO; +} + +ssize_t fgetxattrat_fake(int dirfd, const char *filename, const char *attribute, void *value, size_t size, int flags) { + _cleanup_close_ int fd = -1; + ssize_t l; + + /* The kernel doesn't have a fgetxattrat() command, hence let's emulate one */ + + fd = openat(dirfd, filename, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOATIME|(flags & AT_SYMLINK_NOFOLLOW ? O_NOFOLLOW : 0)); + if (fd < 0) + return -errno; + + l = fgetxattr(fd, attribute, value, size); + if (l < 0) + return -errno; + + return l; +} + +static int parse_crtime(le64_t le, usec_t *usec) { + uint64_t u; + + assert(usec); + + u = le64toh(le); + if (u == 0 || u == (uint64_t) -1) + return -EIO; + + *usec = (usec_t) u; + return 0; +} + +int fd_getcrtime(int fd, usec_t *usec) { + le64_t le; + ssize_t n; + + assert(fd >= 0); + assert(usec); + + /* Until Linux gets a real concept of birthtime/creation time, + * let's fake one with xattrs */ + + n = fgetxattr(fd, "user.crtime_usec", &le, sizeof(le)); + if (n < 0) + return -errno; + if (n != sizeof(le)) + return -EIO; + + return parse_crtime(le, usec); +} + +int fd_getcrtime_at(int dirfd, const char *name, usec_t *usec, int flags) { + le64_t le; + ssize_t n; + + n = fgetxattrat_fake(dirfd, name, "user.crtime_usec", &le, sizeof(le), flags); + if (n < 0) + return -errno; + if (n != sizeof(le)) + return -EIO; + + return parse_crtime(le, usec); +} + +int path_getcrtime(const char *p, usec_t *usec) { + le64_t le; + ssize_t n; + + assert(p); + assert(usec); + + n = getxattr(p, "user.crtime_usec", &le, sizeof(le)); + if (n < 0) + return -errno; + if (n != sizeof(le)) + return -EIO; + + return parse_crtime(le, usec); +} + +int fd_setcrtime(int fd, usec_t usec) { + le64_t le; + + assert(fd >= 0); + + if (usec <= 0) + usec = now(CLOCK_REALTIME); + + le = htole64((uint64_t) usec); + if (fsetxattr(fd, "user.crtime_usec", &le, sizeof(le), 0) < 0) + return -errno; + + return 0; +} + +int same_fd(int a, int b) { + struct stat sta, stb; + pid_t pid; + int r, fa, fb; + + assert(a >= 0); + assert(b >= 0); + + /* Compares two file descriptors. Note that semantics are + * quite different depending on whether we have kcmp() or we + * don't. If we have kcmp() this will only return true for + * dup()ed file descriptors, but not otherwise. If we don't + * have kcmp() this will also return true for two fds of the same + * file, created by separate open() calls. Since we use this + * call mostly for filtering out duplicates in the fd store + * this difference hopefully doesn't matter too much. */ + + if (a == b) + return true; + + /* Try to use kcmp() if we have it. */ + pid = getpid(); + r = kcmp(pid, pid, KCMP_FILE, a, b); + if (r == 0) + return true; + if (r > 0) + return false; + if (errno != ENOSYS) + return -errno; + + /* We don't have kcmp(), use fstat() instead. */ + if (fstat(a, &sta) < 0) + return -errno; + + if (fstat(b, &stb) < 0) + return -errno; + + if ((sta.st_mode & S_IFMT) != (stb.st_mode & S_IFMT)) + return false; + + /* We consider all device fds different, since two device fds + * might refer to quite different device contexts even though + * they share the same inode and backing dev_t. */ + + if (S_ISCHR(sta.st_mode) || S_ISBLK(sta.st_mode)) + return false; + + if (sta.st_dev != stb.st_dev || sta.st_ino != stb.st_ino) + return false; + + /* The fds refer to the same inode on disk, let's also check + * if they have the same fd flags. This is useful to + * distuingish the read and write side of a pipe created with + * pipe(). */ + fa = fcntl(a, F_GETFL); + if (fa < 0) + return -errno; + + fb = fcntl(b, F_GETFL); + if (fb < 0) + return -errno; + + return fa == fb; +} + +int chattr_fd(int fd, bool b, unsigned mask) { + unsigned old_attr, new_attr; + + assert(fd >= 0); + + if (mask == 0) + return 0; + + if (ioctl(fd, FS_IOC_GETFLAGS, &old_attr) < 0) + return -errno; + + if (b) + new_attr = old_attr | mask; + else + new_attr = old_attr & ~mask; + + if (new_attr == old_attr) + return 0; + + if (ioctl(fd, FS_IOC_SETFLAGS, &new_attr) < 0) + return -errno; + + return 0; +} + +int chattr_path(const char *p, bool b, unsigned mask) { + _cleanup_close_ int fd = -1; + + assert(p); + + if (mask == 0) + return 0; + + fd = open(p, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); + if (fd < 0) + return -errno; + + return chattr_fd(fd, b, mask); +}