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-rw-r--r--src/shared/specifier.c509
1 files changed, 509 insertions, 0 deletions
diff --git a/src/shared/specifier.c b/src/shared/specifier.c
new file mode 100644
index 0000000..911bff2
--- /dev/null
+++ b/src/shared/specifier.c
@@ -0,0 +1,509 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <sys/utsname.h>
+
+#include "sd-id128.h"
+
+#include "alloc-util.h"
+#include "architecture.h"
+#include "chase-symlinks.h"
+#include "fd-util.h"
+#include "format-util.h"
+#include "fs-util.h"
+#include "hostname-util.h"
+#include "id128-util.h"
+#include "macro.h"
+#include "os-util.h"
+#include "path-lookup.h"
+#include "path-util.h"
+#include "specifier.h"
+#include "string-util.h"
+#include "strv.h"
+#include "user-util.h"
+
+/*
+ * Generic infrastructure for replacing %x style specifiers in
+ * strings. Will call a callback for each replacement.
+ */
+
+/* Any ASCII character or digit: our pool of potential specifiers,
+ * and "%" used for escaping. */
+#define POSSIBLE_SPECIFIERS ALPHANUMERICAL "%"
+
+int specifier_printf(const char *text, size_t max_length, const Specifier table[], const char *root, const void *userdata, char **ret) {
+ _cleanup_free_ char *result = NULL;
+ bool percent = false;
+ size_t l;
+ char *t;
+ int r;
+
+ assert(ret);
+ assert(text);
+ assert(table);
+
+ l = strlen(text);
+ if (!GREEDY_REALLOC(result, l + 1))
+ return -ENOMEM;
+ t = result;
+
+ for (const char *f = text; *f != '\0'; f++, l--) {
+ if (percent) {
+ percent = false;
+
+ if (*f == '%')
+ *(t++) = '%';
+ else {
+ const Specifier *i;
+
+ for (i = table; i->specifier; i++)
+ if (i->specifier == *f)
+ break;
+
+ if (i->lookup) {
+ _cleanup_free_ char *w = NULL;
+ size_t k, j;
+
+ r = i->lookup(i->specifier, i->data, root, userdata, &w);
+ if (r < 0)
+ return r;
+ if (isempty(w))
+ continue;
+
+ j = t - result;
+ k = strlen(w);
+
+ if (!GREEDY_REALLOC(result, j + k + l + 1))
+ return -ENOMEM;
+ memcpy(result + j, w, k);
+ t = result + j + k;
+ } else if (strchr(POSSIBLE_SPECIFIERS, *f))
+ /* Oops, an unknown specifier. */
+ return -EBADSLT;
+ else {
+ *(t++) = '%';
+ *(t++) = *f;
+ }
+ }
+ } else if (*f == '%')
+ percent = true;
+ else
+ *(t++) = *f;
+
+ if ((size_t) (t - result) > max_length)
+ return -ENAMETOOLONG;
+ }
+
+ /* If string ended with a stray %, also end with % */
+ if (percent) {
+ *(t++) = '%';
+ if ((size_t) (t - result) > max_length)
+ return -ENAMETOOLONG;
+ }
+ *(t++) = 0;
+
+ *ret = TAKE_PTR(result);
+ return 0;
+}
+
+/* Generic handler for simple string replacements */
+
+int specifier_string(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ char *n = NULL;
+
+ assert(ret);
+
+ if (!isempty(data)) {
+ n = strdup(data);
+ if (!n)
+ return -ENOMEM;
+ }
+
+ *ret = n;
+ return 0;
+}
+
+int specifier_real_path(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ const char *path = data;
+
+ assert(ret);
+
+ if (!path)
+ return -ENOENT;
+
+ return chase_symlinks(path, root, 0, ret, NULL);
+}
+
+int specifier_real_directory(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ _cleanup_free_ char *path = NULL;
+ int r;
+
+ assert(ret);
+
+ r = specifier_real_path(specifier, data, root, userdata, &path);
+ if (r < 0)
+ return r;
+
+ assert(path);
+ return path_extract_directory(path, ret);
+}
+
+int specifier_id128(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ const sd_id128_t *id = ASSERT_PTR(data);
+ char *n;
+
+ n = new(char, SD_ID128_STRING_MAX);
+ if (!n)
+ return -ENOMEM;
+
+ *ret = sd_id128_to_string(*id, n);
+ return 0;
+}
+
+int specifier_uuid(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ const sd_id128_t *id = ASSERT_PTR(data);
+ char *n;
+
+ n = new(char, SD_ID128_UUID_STRING_MAX);
+ if (!n)
+ return -ENOMEM;
+
+ *ret = sd_id128_to_uuid_string(*id, n);
+ return 0;
+}
+
+int specifier_uint64(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ const uint64_t *n = ASSERT_PTR(data);
+
+ return asprintf(ret, "%" PRIu64, *n) < 0 ? -ENOMEM : 0;
+}
+
+int specifier_machine_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ sd_id128_t id;
+ int r;
+
+ assert(ret);
+
+ if (root) {
+ _cleanup_close_ int fd = -1;
+
+ fd = chase_symlinks_and_open("/etc/machine-id", root, CHASE_PREFIX_ROOT, O_RDONLY|O_CLOEXEC|O_NOCTTY, NULL);
+ if (fd < 0)
+ /* Translate error for missing os-release file to EUNATCH. */
+ return fd == -ENOENT ? -EUNATCH : fd;
+
+ r = id128_read_fd(fd, ID128_FORMAT_PLAIN, &id);
+ } else
+ r = sd_id128_get_machine(&id);
+ if (r < 0)
+ return r;
+
+ return specifier_id128(specifier, &id, root, userdata, ret);
+}
+
+int specifier_boot_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ sd_id128_t id;
+ int r;
+
+ assert(ret);
+
+ r = sd_id128_get_boot(&id);
+ if (r < 0)
+ return r;
+
+ return specifier_id128(specifier, &id, root, userdata, ret);
+}
+
+int specifier_hostname(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ char *n;
+
+ assert(ret);
+
+ n = gethostname_malloc();
+ if (!n)
+ return -ENOMEM;
+
+ *ret = n;
+ return 0;
+}
+
+int specifier_short_hostname(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ char *n;
+
+ assert(ret);
+
+ n = gethostname_short_malloc();
+ if (!n)
+ return -ENOMEM;
+
+ *ret = n;
+ return 0;
+}
+
+int specifier_pretty_hostname(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ char *n = NULL;
+
+ assert(ret);
+
+ if (get_pretty_hostname(&n) < 0) {
+ n = gethostname_short_malloc();
+ if (!n)
+ return -ENOMEM;
+ }
+
+ *ret = n;
+ return 0;
+}
+
+int specifier_kernel_release(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ struct utsname uts;
+ char *n;
+
+ assert(ret);
+
+ if (uname(&uts) < 0)
+ return -errno;
+
+ n = strdup(uts.release);
+ if (!n)
+ return -ENOMEM;
+
+ *ret = n;
+ return 0;
+}
+
+int specifier_architecture(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ char *t;
+
+ assert(ret);
+
+ t = strdup(architecture_to_string(uname_architecture()));
+ if (!t)
+ return -ENOMEM;
+
+ *ret = t;
+ return 0;
+}
+
+/* Note: fields in /etc/os-release might quite possibly be missing, even if everything is entirely valid
+ * otherwise. We'll return an empty value or NULL in that case from the functions below. But if the
+ * os-release file is missing, we'll return -EUNATCH. This means that something is seriously wrong with the
+ * installation. */
+
+static int parse_os_release_specifier(const char *root, const char *id, char **ret) {
+ _cleanup_free_ char *v = NULL;
+ int r;
+
+ assert(ret);
+
+ r = parse_os_release(root, id, &v);
+ if (r >= 0)
+ /* parse_os_release() calls parse_env_file() which only sets the return value for
+ * entries found. Let's make sure we set the return value in all cases. */
+ *ret = TAKE_PTR(v);
+
+ /* Translate error for missing os-release file to EUNATCH. */
+ return r == -ENOENT ? -EUNATCH : r;
+}
+
+int specifier_os_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ return parse_os_release_specifier(root, "ID", ret);
+}
+
+int specifier_os_version_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ return parse_os_release_specifier(root, "VERSION_ID", ret);
+}
+
+int specifier_os_build_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ return parse_os_release_specifier(root, "BUILD_ID", ret);
+}
+
+int specifier_os_variant_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ return parse_os_release_specifier(root, "VARIANT_ID", ret);
+}
+
+int specifier_os_image_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ return parse_os_release_specifier(root, "IMAGE_ID", ret);
+}
+
+int specifier_os_image_version(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ return parse_os_release_specifier(root, "IMAGE_VERSION", ret);
+}
+
+int specifier_group_name(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ LookupScope scope = PTR_TO_INT(data);
+ char *t;
+
+ assert(ret);
+
+ if (scope == LOOKUP_SCOPE_GLOBAL)
+ return -EINVAL;
+
+ t = gid_to_name(scope == LOOKUP_SCOPE_USER ? getgid() : 0);
+ if (!t)
+ return -ENOMEM;
+
+ *ret = t;
+ return 0;
+}
+
+int specifier_group_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ LookupScope scope = PTR_TO_INT(data);
+ gid_t gid;
+
+ assert(ret);
+
+ if (scope == LOOKUP_SCOPE_GLOBAL)
+ return -EINVAL;
+
+ gid = scope == LOOKUP_SCOPE_USER ? getgid() : 0;
+
+ if (asprintf(ret, UID_FMT, gid) < 0)
+ return -ENOMEM;
+
+ return 0;
+}
+
+int specifier_user_name(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ LookupScope scope = PTR_TO_INT(data);
+ uid_t uid;
+ char *t;
+
+ assert(ret);
+
+ if (scope == LOOKUP_SCOPE_GLOBAL)
+ return -EINVAL;
+
+ uid = scope == LOOKUP_SCOPE_USER ? getuid() : 0;
+
+ /* If we are UID 0 (root), this will not result in NSS, otherwise it might. This is good, as we want
+ * to be able to run this in PID 1, where our user ID is 0, but where NSS lookups are not allowed.
+
+ * We don't use getusername_malloc() here, because we don't want to look at $USER, to remain
+ * consistent with specifer_user_id() below.
+ */
+
+ t = uid_to_name(uid);
+ if (!t)
+ return -ENOMEM;
+
+ *ret = t;
+ return 0;
+}
+
+int specifier_user_id(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ LookupScope scope = PTR_TO_INT(data);
+ uid_t uid;
+
+ assert(ret);
+
+ if (scope == LOOKUP_SCOPE_GLOBAL)
+ return -EINVAL;
+
+ uid = scope == LOOKUP_SCOPE_USER ? getuid() : 0;
+
+ if (asprintf(ret, UID_FMT, uid) < 0)
+ return -ENOMEM;
+
+ return 0;
+}
+
+int specifier_user_home(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ assert(ret);
+
+ /* On PID 1 (which runs as root) this will not result in NSS,
+ * which is good. See above */
+
+ return get_home_dir(ret);
+}
+
+int specifier_user_shell(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ assert(ret);
+
+ /* On PID 1 (which runs as root) this will not result in NSS,
+ * which is good. See above */
+
+ return get_shell(ret);
+}
+
+int specifier_tmp_dir(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ const char *p;
+ char *copy;
+ int r;
+
+ assert(ret);
+
+ if (root) /* If root dir is set, don't honour $TMP or similar */
+ p = "/tmp";
+ else {
+ r = tmp_dir(&p);
+ if (r < 0)
+ return r;
+ }
+ copy = strdup(p);
+ if (!copy)
+ return -ENOMEM;
+
+ *ret = copy;
+ return 0;
+}
+
+int specifier_var_tmp_dir(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+ const char *p;
+ char *copy;
+ int r;
+
+ assert(ret);
+
+ if (root)
+ p = "/var/tmp";
+ else {
+ r = var_tmp_dir(&p);
+ if (r < 0)
+ return r;
+ }
+ copy = strdup(p);
+ if (!copy)
+ return -ENOMEM;
+
+ *ret = copy;
+ return 0;
+}
+
+int specifier_escape_strv(char **l, char ***ret) {
+ char **z, **p, **q;
+
+ assert(ret);
+
+ if (strv_isempty(l)) {
+ *ret = NULL;
+ return 0;
+ }
+
+ z = new(char*, strv_length(l)+1);
+ if (!z)
+ return -ENOMEM;
+
+ for (p = l, q = z; *p; p++, q++) {
+
+ *q = specifier_escape(*p);
+ if (!*q) {
+ strv_free(z);
+ return -ENOMEM;
+ }
+ }
+
+ *q = NULL;
+ *ret = z;
+
+ return 0;
+}
+
+const Specifier system_and_tmp_specifier_table[] = {
+ COMMON_SYSTEM_SPECIFIERS,
+ COMMON_TMP_SPECIFIERS,
+ {}
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 04:40:09 +0000