diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/core/namespace.c | 2 | ||||
-rw-r--r-- | src/nspawn/nspawn.c | 445 |
2 files changed, 337 insertions, 110 deletions
diff --git a/src/core/namespace.c b/src/core/namespace.c index 718da2384d..bee2839f54 100644 --- a/src/core/namespace.c +++ b/src/core/namespace.c @@ -87,7 +87,7 @@ static int mount_path_compare(const void *a, const void *b) { d = path_compare(p->path, q->path); - if (!d) { + if (d == 0) { /* If the paths are equal, check the mode */ if (p->mode < q->mode) return -1; diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 2f7dd53bd0..8c91726aeb 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -125,6 +125,22 @@ typedef enum Volatile { VOLATILE_STATE, } Volatile; +typedef enum CustomMountType { + CUSTOM_MOUNT_BIND, + CUSTOM_MOUNT_TMPFS, + CUSTOM_MOUNT_OVERLAY, +} CustomMountType; + +typedef struct CustomMount { + CustomMountType type; + bool read_only; + char *source; /* for overlayfs this is the upper directory */ + char *destination; + char *options; + char *work_dir; + char **lower; +} CustomMount; + static char *arg_directory = NULL; static char *arg_template = NULL; static char *arg_user = NULL; @@ -166,9 +182,8 @@ static uint64_t arg_retain = (1ULL << CAP_AUDIT_WRITE) | (1ULL << CAP_AUDIT_CONTROL) | (1ULL << CAP_MKNOD); -static char **arg_bind = NULL; -static char **arg_bind_ro = NULL; -static char **arg_tmpfs = NULL; +static CustomMount *arg_custom_mounts = NULL; +static unsigned arg_n_custom_mounts = 0; static char **arg_setenv = NULL; static bool arg_quiet = false; static bool arg_share_system = false; @@ -244,6 +259,11 @@ static void help(void) { " the container\n" " --bind-ro=PATH[:PATH] Similar, but creates a read-only bind mount\n" " --tmpfs=PATH:[OPTIONS] Mount an empty tmpfs to the specified directory\n" + " --overlay=PATH[:PATH...]:PATH\n" + " Create an overlay mount from the host to \n" + " the container\n" + " --overlay-ro=PATH[:PATH...]:PATH\n" + " Similar, but creates a read-only overlay mount\n" " --setenv=NAME=VALUE Pass an environment variable to PID 1\n" " --share-system Share system namespaces with host\n" " --register=BOOLEAN Register container as machine\n" @@ -253,6 +273,89 @@ static void help(void) { , program_invocation_short_name); } +static CustomMount* custom_mount_add(CustomMountType t) { + CustomMount *c, *ret; + + c = realloc(arg_custom_mounts, (arg_n_custom_mounts + 1) * sizeof(CustomMount)); + if (!c) + return NULL; + + arg_custom_mounts = c; + ret = arg_custom_mounts + arg_n_custom_mounts; + arg_n_custom_mounts++; + + *ret = (CustomMount) { .type = t }; + + return ret; +} + +static void custom_mount_free_all(void) { + unsigned i; + + for (i = 0; i < arg_n_custom_mounts; i++) { + CustomMount *m = &arg_custom_mounts[i]; + + free(m->source); + free(m->destination); + free(m->options); + + if (m->work_dir) { + (void) rm_rf(m->work_dir, REMOVE_ROOT|REMOVE_PHYSICAL); + free(m->work_dir); + } + + strv_free(m->lower); + } + + free(arg_custom_mounts); + arg_custom_mounts = NULL; + arg_n_custom_mounts = 0; +} + +static int custom_mount_compare(const void *a, const void *b) { + const CustomMount *x = a, *y = b; + int r; + + r = path_compare(x->destination, y->destination); + if (r != 0) + return r; + + if (x->type < y->type) + return -1; + if (x->type > y->type) + return 1; + + return 0; +} + +static int custom_mounts_prepare(void) { + unsigned i; + int r; + + /* Ensure the mounts are applied prefix first. */ + qsort_safe(arg_custom_mounts, arg_n_custom_mounts, sizeof(CustomMount), custom_mount_compare); + + /* Allocate working directories for the overlay file systems that need it */ + for (i = 0; i < arg_n_custom_mounts; i++) { + CustomMount *m = &arg_custom_mounts[i]; + + if (m->type != CUSTOM_MOUNT_OVERLAY) + continue; + + if (m->work_dir) + continue; + + if (m->read_only) + continue; + + r = tempfn_random(m->source, &m->work_dir); + if (r < 0) + return log_error_errno(r, "Failed to generate work directory from %s: %m", m->source); + } + + return 0; +} + static int set_sanitized_path(char **b, const char *path) { char *p; @@ -287,6 +390,8 @@ static int parse_argv(int argc, char *argv[]) { ARG_BIND, ARG_BIND_RO, ARG_TMPFS, + ARG_OVERLAY, + ARG_OVERLAY_RO, ARG_SETENV, ARG_SHARE_SYSTEM, ARG_REGISTER, @@ -320,6 +425,8 @@ static int parse_argv(int argc, char *argv[]) { { "bind", required_argument, NULL, ARG_BIND }, { "bind-ro", required_argument, NULL, ARG_BIND_RO }, { "tmpfs", required_argument, NULL, ARG_TMPFS }, + { "overlay", required_argument, NULL, ARG_OVERLAY }, + { "overlay-ro", required_argument, NULL, ARG_OVERLAY_RO }, { "machine", required_argument, NULL, 'M' }, { "slice", required_argument, NULL, 'S' }, { "setenv", required_argument, NULL, ARG_SETENV }, @@ -544,72 +651,131 @@ static int parse_argv(int argc, char *argv[]) { case ARG_BIND: case ARG_BIND_RO: { - _cleanup_free_ char *a = NULL, *b = NULL; + _cleanup_free_ char *source = NULL, *destination = NULL; + CustomMount *m; char *e; - char ***x; - - x = c == ARG_BIND ? &arg_bind : &arg_bind_ro; e = strchr(optarg, ':'); if (e) { - a = strndup(optarg, e - optarg); - b = strdup(e + 1); + source = strndup(optarg, e - optarg); + destination = strdup(e + 1); } else { - a = strdup(optarg); - b = strdup(optarg); + source = strdup(optarg); + destination = strdup(optarg); } - if (!a || !b) + if (!source || !destination) return log_oom(); - if (!path_is_absolute(a) || !path_is_absolute(b)) { + if (!path_is_absolute(source) || !path_is_absolute(destination)) { log_error("Invalid bind mount specification: %s", optarg); return -EINVAL; } - r = strv_extend(x, a); - if (r < 0) + m = custom_mount_add(CUSTOM_MOUNT_BIND); + if (!m) return log_oom(); - r = strv_extend(x, b); - if (r < 0) - return log_oom(); + m->source = source; + m->destination = destination; + m->read_only = c == ARG_BIND_RO; + + source = destination = NULL; break; } case ARG_TMPFS: { - _cleanup_free_ char *a = NULL, *b = NULL; + _cleanup_free_ char *path = NULL, *opts = NULL; + CustomMount *m; char *e; e = strchr(optarg, ':'); if (e) { - a = strndup(optarg, e - optarg); - b = strdup(e + 1); + path = strndup(optarg, e - optarg); + opts = strdup(e + 1); } else { - a = strdup(optarg); - b = strdup("mode=0755"); + path = strdup(optarg); + opts = strdup("mode=0755"); } - if (!a || !b) + if (!path || !opts) return log_oom(); - if (!path_is_absolute(a)) { + if (!path_is_absolute(path)) { log_error("Invalid tmpfs specification: %s", optarg); return -EINVAL; } - r = strv_push(&arg_tmpfs, a); - if (r < 0) + m = custom_mount_add(CUSTOM_MOUNT_TMPFS); + if (!m) return log_oom(); - a = NULL; + m->destination = path; + m->options = opts; - r = strv_push(&arg_tmpfs, b); - if (r < 0) + path = opts = NULL; + + break; + } + + case ARG_OVERLAY: + case ARG_OVERLAY_RO: { + _cleanup_free_ char *upper = NULL, *destination = NULL; + _cleanup_strv_free_ char **lower = NULL; + CustomMount *m; + unsigned n = 0; + char **i; + + lower = strv_split(optarg, ":"); + if (!lower) return log_oom(); - b = NULL; + STRV_FOREACH(i, lower) { + if (!path_is_absolute(*i)) { + log_error("Overlay path %s is not absolute.", *i); + return -EINVAL; + } + + n++; + } + + if (n < 2) { + log_error("--overlay= needs at least two colon-separated directories specified."); + return -EINVAL; + } + + if (n == 2) { + /* If two parameters are specified, + * the first one is the lower, the + * second one the upper directory. And + * we'll also define the the + * destination mount point the same as + * the upper. */ + upper = lower[1]; + lower[1] = NULL; + + destination = strdup(upper); + if (!destination) + return log_oom(); + + } else { + upper = lower[n - 2]; + destination = lower[n - 1]; + lower[n - 2] = NULL; + } + + m = custom_mount_add(CUSTOM_MOUNT_OVERLAY); + if (!m) + return log_oom(); + + m->destination = destination; + m->source = upper; + m->lower = lower; + m->read_only = c == ARG_OVERLAY_RO; + + upper = destination = NULL; + lower = NULL; break; } @@ -964,62 +1130,149 @@ static int mount_all(const char *dest) { return r; } -static int mount_binds(const char *dest, char **l, bool ro) { - char **x, **y; +static int mount_bind(const char *dest, CustomMount *m) { + struct stat source_st, dest_st; + char *where; + int r; - STRV_FOREACH_PAIR(x, y, l) { - _cleanup_free_ char *where = NULL; - struct stat source_st, dest_st; - int r; + assert(dest); + assert(m); - if (stat(*x, &source_st) < 0) - return log_error_errno(errno, "Failed to stat %s: %m", *x); + if (stat(m->source, &source_st) < 0) + return log_error_errno(errno, "Failed to stat %s: %m", m->source); - where = strappend(dest, *y); - if (!where) - return log_oom(); + where = strjoina(dest, m->destination); - r = stat(where, &dest_st); - if (r == 0) { - if (S_ISDIR(source_st.st_mode) && !S_ISDIR(dest_st.st_mode)) { - log_error("Cannot bind mount directory %s on file %s.", *x, where); - return -EINVAL; - } - if (!S_ISDIR(source_st.st_mode) && S_ISDIR(dest_st.st_mode)) { - log_error("Cannot bind mount file %s on directory %s.", *x, where); - return -EINVAL; - } - } else if (errno == ENOENT) { - r = mkdir_parents_label(where, 0755); - if (r < 0) - return log_error_errno(r, "Failed to bind mount %s: %m", *x); - } else { - log_error_errno(errno, "Failed to bind mount %s: %m", *x); - return -errno; + r = stat(where, &dest_st); + if (r >= 0) { + if (S_ISDIR(source_st.st_mode) && !S_ISDIR(dest_st.st_mode)) { + log_error("Cannot bind mount directory %s on file %s.", m->source, where); + return -EINVAL; } - /* Create the mount point. Any non-directory file can be - * mounted on any non-directory file (regular, fifo, socket, - * char, block). - */ - if (S_ISDIR(source_st.st_mode)) { - r = mkdir_label(where, 0755); - if (r < 0 && errno != EEXIST) - return log_error_errno(r, "Failed to create mount point %s: %m", where); - } else { - r = touch(where); - if (r < 0) - return log_error_errno(r, "Failed to create mount point %s: %m", where); + if (!S_ISDIR(source_st.st_mode) && S_ISDIR(dest_st.st_mode)) { + log_error("Cannot bind mount file %s on directory %s.", m->source, where); + return -EINVAL; } - if (mount(*x, where, NULL, MS_BIND, NULL) < 0) - return log_error_errno(errno, "mount(%s) failed: %m", where); + } else if (errno == ENOENT) { + r = mkdir_parents_label(where, 0755); + if (r < 0) + return log_error_errno(r, "Failed to make parents of %s: %m", where); + } else { + log_error_errno(errno, "Failed to stat %s: %m", where); + return -errno; + } - if (ro) { - r = bind_remount_recursive(where, true); - if (r < 0) - return log_error_errno(r, "Read-Only bind mount failed: %m"); + /* Create the mount point. Any non-directory file can be + * mounted on any non-directory file (regular, fifo, socket, + * char, block). + */ + if (S_ISDIR(source_st.st_mode)) + r = mkdir_label(where, 0755); + else + r = touch(where); + if (r < 0 && r != -EEXIST) + return log_error_errno(r, "Failed to create mount point %s: %m", where); + + if (mount(m->source, where, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "mount(%s) failed: %m", where); + + if (m->read_only) { + r = bind_remount_recursive(where, true); + if (r < 0) + return log_error_errno(r, "Read-only bind mount failed: %m"); + } + + return 0; +} + +static int mount_tmpfs(const char *dest, CustomMount *m) { + char *where; + int r; + + assert(dest); + assert(m); + + where = strjoina(dest, m->destination); + + r = mkdir_label(where, 0755); + if (r < 0 && r != -EEXIST) + return log_error_errno(r, "Creating mount point for tmpfs %s failed: %m", where); + + if (mount("tmpfs", where, "tmpfs", MS_NODEV|MS_STRICTATIME, m->options) < 0) + return log_error_errno(errno, "tmpfs mount to %s failed: %m", where); + + return 0; +} + +static int mount_overlay(const char *dest, CustomMount *m) { + _cleanup_free_ char *lower = NULL; + char *where, *options; + int r; + + assert(dest); + assert(m); + + where = strjoina(dest, m->destination); + + r = mkdir_label(where, 0755); + if (r < 0 && r != -EEXIST) + return log_error_errno(r, "Creating mount point for overlay %s failed: %m", where); + + (void) mkdir_p_label(m->source, 0755); + + strv_reverse(m->lower); + lower = strv_join(m->lower, ":"); + strv_reverse(m->lower); + + if (!lower) + return log_oom(); + + if (m->read_only) + options = strjoina("lowerdir=", m->source, ":", lower); + else { + assert(m->work_dir); + (void) mkdir_label(m->work_dir, 0700); + + options = strjoina("lowerdir=", lower, ",upperdir=", m->source, ",workdir=", m->work_dir); + } + + if (mount("overlay", where, "overlay", m->read_only ? MS_RDONLY : 0, options) < 0) + return log_error_errno(errno, "overlay mount to %s failed: %m", where); + + return 0; +} + +static int mount_custom(const char *dest) { + unsigned i; + int r; + + assert(dest); + + for (i = 0; i < arg_n_custom_mounts; i++) { + CustomMount *m = &arg_custom_mounts[i]; + + switch (m->type) { + + case CUSTOM_MOUNT_BIND: + r = mount_bind(dest, m); + break; + + case CUSTOM_MOUNT_TMPFS: + r = mount_tmpfs(dest, m); + break; + + case CUSTOM_MOUNT_OVERLAY: + r = mount_overlay(dest, m); + break; + + default: + assert_not_reached("Unknown custom mount type"); } + + if (r < 0) + return r; } return 0; @@ -1139,28 +1392,6 @@ static int mount_cgroup(const char *dest) { return 0; } -static int mount_tmpfs(const char *dest) { - char **i, **o; - - STRV_FOREACH_PAIR(i, o, arg_tmpfs) { - _cleanup_free_ char *where = NULL; - int r; - - where = strappend(dest, *i); - if (!where) - return log_oom(); - - r = mkdir_label(where, 0755); - if (r < 0 && r != -EEXIST) - return log_error_errno(r, "Creating mount point for tmpfs %s failed: %m", where); - - if (mount("tmpfs", where, "tmpfs", MS_NODEV|MS_STRICTATIME, *o) < 0) - return log_error_errno(errno, "tmpfs mount to %s failed: %m", where); - } - - return 0; -} - static int setup_timezone(const char *dest) { _cleanup_free_ char *where = NULL, *p = NULL, *q = NULL, *check = NULL, *what = NULL; char *z, *y; @@ -3889,6 +4120,10 @@ int main(int argc, char *argv[]) { if (r < 0) goto finish; + r = custom_mounts_prepare(); + if (r < 0) + goto finish; + interactive = isatty(STDIN_FILENO) > 0 && isatty(STDOUT_FILENO) > 0; master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY); @@ -4126,13 +4361,7 @@ int main(int argc, char *argv[]) { if (setup_journal(arg_directory) < 0) _exit(EXIT_FAILURE); - if (mount_binds(arg_directory, arg_bind, false) < 0) - _exit(EXIT_FAILURE); - - if (mount_binds(arg_directory, arg_bind_ro, true) < 0) - _exit(EXIT_FAILURE); - - if (mount_tmpfs(arg_directory) < 0) + if (mount_custom(arg_directory) < 0) _exit(EXIT_FAILURE); /* Wait until we are cgroup-ified, so that we @@ -4505,9 +4734,7 @@ finish: strv_free(arg_network_interfaces); strv_free(arg_network_macvlan); strv_free(arg_network_ipvlan); - strv_free(arg_bind); - strv_free(arg_bind_ro); - strv_free(arg_tmpfs); + custom_mount_free_all(); flush_ports(&exposed); |