diff options
Diffstat (limited to 'src/basic/unit-name.c')
| -rw-r--r-- | src/basic/unit-name.c | 834 |
1 files changed, 834 insertions, 0 deletions
diff --git a/src/basic/unit-name.c b/src/basic/unit-name.c new file mode 100644 index 0000000000..bf52463d81 --- /dev/null +++ b/src/basic/unit-name.c @@ -0,0 +1,834 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <string.h> + +#include "path-util.h" +#include "bus-label.h" +#include "util.h" +#include "unit-name.h" +#include "def.h" +#include "strv.h" + +#define VALID_CHARS \ + DIGITS LETTERS \ + ":-_.\\" + +bool unit_name_is_valid(const char *n, UnitNameFlags flags) { + const char *e, *i, *at; + + assert((flags & ~(UNIT_NAME_PLAIN|UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE)) == 0); + + if (_unlikely_(flags == 0)) + return false; + + if (isempty(n)) + return false; + + if (strlen(n) >= UNIT_NAME_MAX) + return false; + + e = strrchr(n, '.'); + if (!e || e == n) + return false; + + if (unit_type_from_string(e + 1) < 0) + return false; + + for (i = n, at = NULL; i < e; i++) { + + if (*i == '@' && !at) + at = i; + + if (!strchr("@" VALID_CHARS, *i)) + return false; + } + + if (at == n) + return false; + + if (flags & UNIT_NAME_PLAIN) + if (!at) + return true; + + if (flags & UNIT_NAME_INSTANCE) + if (at && e > at + 1) + return true; + + if (flags & UNIT_NAME_TEMPLATE) + if (at && e == at + 1) + return true; + + return false; +} + +bool unit_prefix_is_valid(const char *p) { + + /* We don't allow additional @ in the prefix string */ + + if (isempty(p)) + return false; + + return in_charset(p, VALID_CHARS); +} + +bool unit_instance_is_valid(const char *i) { + + /* The max length depends on the length of the string, so we + * don't really check this here. */ + + if (isempty(i)) + return false; + + /* We allow additional @ in the instance string, we do not + * allow them in the prefix! */ + + return in_charset(i, "@" VALID_CHARS); +} + +bool unit_suffix_is_valid(const char *s) { + if (isempty(s)) + return false; + + if (s[0] != '.') + return false; + + if (unit_type_from_string(s + 1) < 0) + return false; + + return true; +} + +int unit_name_to_prefix(const char *n, char **ret) { + const char *p; + char *s; + + assert(n); + assert(ret); + + if (!unit_name_is_valid(n, UNIT_NAME_ANY)) + return -EINVAL; + + p = strchr(n, '@'); + if (!p) + p = strrchr(n, '.'); + + assert_se(p); + + s = strndup(n, p - n); + if (!s) + return -ENOMEM; + + *ret = s; + return 0; +} + +int unit_name_to_instance(const char *n, char **instance) { + const char *p, *d; + char *i; + + assert(n); + assert(instance); + + if (!unit_name_is_valid(n, UNIT_NAME_ANY)) + return -EINVAL; + + /* Everything past the first @ and before the last . is the instance */ + p = strchr(n, '@'); + if (!p) { + *instance = NULL; + return 0; + } + + p++; + + d = strrchr(p, '.'); + if (!d) + return -EINVAL; + + i = strndup(p, d-p); + if (!i) + return -ENOMEM; + + *instance = i; + return 1; +} + +int unit_name_to_prefix_and_instance(const char *n, char **ret) { + const char *d; + char *s; + + assert(n); + assert(ret); + + if (!unit_name_is_valid(n, UNIT_NAME_ANY)) + return -EINVAL; + + d = strrchr(n, '.'); + if (!d) + return -EINVAL; + + s = strndup(n, d - n); + if (!s) + return -ENOMEM; + + *ret = s; + return 0; +} + +UnitType unit_name_to_type(const char *n) { + const char *e; + + assert(n); + + if (!unit_name_is_valid(n, UNIT_NAME_ANY)) + return _UNIT_TYPE_INVALID; + + assert_se(e = strrchr(n, '.')); + + return unit_type_from_string(e + 1); +} + +int unit_name_change_suffix(const char *n, const char *suffix, char **ret) { + char *e, *s; + size_t a, b; + + assert(n); + assert(suffix); + assert(ret); + + if (!unit_name_is_valid(n, UNIT_NAME_ANY)) + return -EINVAL; + + if (!unit_suffix_is_valid(suffix)) + return -EINVAL; + + assert_se(e = strrchr(n, '.')); + + a = e - n; + b = strlen(suffix); + + s = new(char, a + b + 1); + if (!s) + return -ENOMEM; + + strcpy(mempcpy(s, n, a), suffix); + *ret = s; + + return 0; +} + +int unit_name_build(const char *prefix, const char *instance, const char *suffix, char **ret) { + char *s; + + assert(prefix); + assert(suffix); + assert(ret); + + if (!unit_prefix_is_valid(prefix)) + return -EINVAL; + + if (instance && !unit_instance_is_valid(instance)) + return -EINVAL; + + if (!unit_suffix_is_valid(suffix)) + return -EINVAL; + + if (!instance) + s = strappend(prefix, suffix); + else + s = strjoin(prefix, "@", instance, suffix, NULL); + if (!s) + return -ENOMEM; + + *ret = s; + return 0; +} + +static char *do_escape_char(char c, char *t) { + assert(t); + + *(t++) = '\\'; + *(t++) = 'x'; + *(t++) = hexchar(c >> 4); + *(t++) = hexchar(c); + + return t; +} + +static char *do_escape(const char *f, char *t) { + assert(f); + assert(t); + + /* do not create units with a leading '.', like for "/.dotdir" mount points */ + if (*f == '.') { + t = do_escape_char(*f, t); + f++; + } + + for (; *f; f++) { + if (*f == '/') + *(t++) = '-'; + else if (*f == '-' || *f == '\\' || !strchr(VALID_CHARS, *f)) + t = do_escape_char(*f, t); + else + *(t++) = *f; + } + + return t; +} + +char *unit_name_escape(const char *f) { + char *r, *t; + + assert(f); + + r = new(char, strlen(f)*4+1); + if (!r) + return NULL; + + t = do_escape(f, r); + *t = 0; + + return r; +} + +int unit_name_unescape(const char *f, char **ret) { + _cleanup_free_ char *r = NULL; + char *t; + + assert(f); + + r = strdup(f); + if (!r) + return -ENOMEM; + + for (t = r; *f; f++) { + if (*f == '-') + *(t++) = '/'; + else if (*f == '\\') { + int a, b; + + if (f[1] != 'x') + return -EINVAL; + + a = unhexchar(f[2]); + if (a < 0) + return -EINVAL; + + b = unhexchar(f[3]); + if (b < 0) + return -EINVAL; + + *(t++) = (char) (((uint8_t) a << 4U) | (uint8_t) b); + f += 3; + } else + *(t++) = *f; + } + + *t = 0; + + *ret = r; + r = NULL; + + return 0; +} + +int unit_name_path_escape(const char *f, char **ret) { + char *p, *s; + + assert(f); + assert(ret); + + p = strdupa(f); + if (!p) + return -ENOMEM; + + path_kill_slashes(p); + + if (STR_IN_SET(p, "/", "")) + s = strdup("-"); + else { + char *e; + + if (!path_is_safe(p)) + return -EINVAL; + + /* Truncate trailing slashes */ + e = endswith(p, "/"); + if (e) + *e = 0; + + /* Truncate leading slashes */ + if (p[0] == '/') + p++; + + s = unit_name_escape(p); + } + if (!s) + return -ENOMEM; + + *ret = s; + return 0; +} + +int unit_name_path_unescape(const char *f, char **ret) { + char *s; + int r; + + assert(f); + + if (isempty(f)) + return -EINVAL; + + if (streq(f, "-")) { + s = strdup("/"); + if (!s) + return -ENOMEM; + } else { + char *w; + + r = unit_name_unescape(f, &w); + if (r < 0) + return r; + + /* Don't accept trailing or leading slashes */ + if (startswith(w, "/") || endswith(w, "/")) { + free(w); + return -EINVAL; + } + + /* Prefix a slash again */ + s = strappend("/", w); + free(w); + if (!s) + return -ENOMEM; + + if (!path_is_safe(s)) { + free(s); + return -EINVAL; + } + } + + if (ret) + *ret = s; + else + free(s); + + return 0; +} + +int unit_name_replace_instance(const char *f, const char *i, char **ret) { + const char *p, *e; + char *s; + size_t a, b; + + assert(f); + assert(i); + assert(ret); + + if (!unit_name_is_valid(f, UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE)) + return -EINVAL; + if (!unit_instance_is_valid(i)) + return -EINVAL; + + assert_se(p = strchr(f, '@')); + assert_se(e = strrchr(f, '.')); + + a = p - f; + b = strlen(i); + + s = new(char, a + 1 + b + strlen(e) + 1); + if (!s) + return -ENOMEM; + + strcpy(mempcpy(mempcpy(s, f, a + 1), i, b), e); + + *ret = s; + return 0; +} + +int unit_name_template(const char *f, char **ret) { + const char *p, *e; + char *s; + size_t a; + + assert(f); + assert(ret); + + if (!unit_name_is_valid(f, UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE)) + return -EINVAL; + + assert_se(p = strchr(f, '@')); + assert_se(e = strrchr(f, '.')); + + a = p - f; + + s = new(char, a + 1 + strlen(e) + 1); + if (!s) + return -ENOMEM; + + strcpy(mempcpy(s, f, a + 1), e); + + *ret = s; + return 0; +} + +int unit_name_from_path(const char *path, const char *suffix, char **ret) { + _cleanup_free_ char *p = NULL; + char *s = NULL; + int r; + + assert(path); + assert(suffix); + assert(ret); + + if (!unit_suffix_is_valid(suffix)) + return -EINVAL; + + r = unit_name_path_escape(path, &p); + if (r < 0) + return r; + + s = strappend(p, suffix); + if (!s) + return -ENOMEM; + + *ret = s; + return 0; +} + +int unit_name_from_path_instance(const char *prefix, const char *path, const char *suffix, char **ret) { + _cleanup_free_ char *p = NULL; + char *s; + int r; + + assert(prefix); + assert(path); + assert(suffix); + assert(ret); + + if (!unit_prefix_is_valid(prefix)) + return -EINVAL; + + if (!unit_suffix_is_valid(suffix)) + return -EINVAL; + + r = unit_name_path_escape(path, &p); + if (r < 0) + return r; + + s = strjoin(prefix, "@", p, suffix, NULL); + if (!s) + return -ENOMEM; + + *ret = s; + return 0; +} + +int unit_name_to_path(const char *name, char **ret) { + _cleanup_free_ char *prefix = NULL; + int r; + + assert(name); + + r = unit_name_to_prefix(name, &prefix); + if (r < 0) + return r; + + return unit_name_path_unescape(prefix, ret); +} + +char *unit_dbus_path_from_name(const char *name) { + _cleanup_free_ char *e = NULL; + + assert(name); + + e = bus_label_escape(name); + if (!e) + return NULL; + + return strappend("/org/freedesktop/systemd1/unit/", e); +} + +int unit_name_from_dbus_path(const char *path, char **name) { + const char *e; + char *n; + + e = startswith(path, "/org/freedesktop/systemd1/unit/"); + if (!e) + return -EINVAL; + + n = bus_label_unescape(e); + if (!n) + return -ENOMEM; + + *name = n; + return 0; +} + +static char *do_escape_mangle(const char *f, UnitNameMangle allow_globs, char *t) { + const char *valid_chars; + + assert(f); + assert(IN_SET(allow_globs, UNIT_NAME_GLOB, UNIT_NAME_NOGLOB)); + assert(t); + + /* We'll only escape the obvious characters here, to play + * safe. */ + + valid_chars = allow_globs == UNIT_NAME_GLOB ? "@" VALID_CHARS "[]!-*?" : "@" VALID_CHARS; + + for (; *f; f++) { + if (*f == '/') + *(t++) = '-'; + else if (!strchr(valid_chars, *f)) + t = do_escape_char(*f, t); + else + *(t++) = *f; + } + + return t; +} + +/** + * Convert a string to a unit name. /dev/blah is converted to dev-blah.device, + * /blah/blah is converted to blah-blah.mount, anything else is left alone, + * except that @suffix is appended if a valid unit suffix is not present. + * + * If @allow_globs, globs characters are preserved. Otherwise they are escaped. + */ +int unit_name_mangle_with_suffix(const char *name, UnitNameMangle allow_globs, const char *suffix, char **ret) { + char *s, *t; + int r; + + assert(name); + assert(suffix); + assert(ret); + + if (isempty(name)) /* We cannot mangle empty unit names to become valid, sorry. */ + return -EINVAL; + + if (!unit_suffix_is_valid(suffix)) + return -EINVAL; + + if (unit_name_is_valid(name, UNIT_NAME_ANY)) { + /* No mangling necessary... */ + s = strdup(name); + if (!s) + return -ENOMEM; + + *ret = s; + return 0; + } + + if (is_device_path(name)) { + r = unit_name_from_path(name, ".device", ret); + if (r >= 0) + return 1; + if (r != -EINVAL) + return r; + } + + if (path_is_absolute(name)) { + r = unit_name_from_path(name, ".mount", ret); + if (r >= 0) + return 1; + if (r != -EINVAL) + return r; + } + + s = new(char, strlen(name) * 4 + strlen(suffix) + 1); + if (!s) + return -ENOMEM; + + t = do_escape_mangle(name, allow_globs, s); + *t = 0; + + if (unit_name_to_type(s) < 0) + strcpy(t, suffix); + + *ret = s; + return 1; +} + +int slice_build_parent_slice(const char *slice, char **ret) { + char *s, *dash; + + assert(slice); + assert(ret); + + if (!slice_name_is_valid(slice)) + return -EINVAL; + + if (streq(slice, "-.slice")) { + *ret = NULL; + return 0; + } + + s = strdup(slice); + if (!s) + return -ENOMEM; + + dash = strrchr(s, '-'); + if (dash) + strcpy(dash, ".slice"); + else { + free(s); + + s = strdup("-.slice"); + if (!s) + return -ENOMEM; + } + + *ret = s; + return 1; +} + +int slice_build_subslice(const char *slice, const char*name, char **ret) { + char *subslice; + + assert(slice); + assert(name); + assert(ret); + + if (!slice_name_is_valid(slice)) + return -EINVAL; + + if (!unit_prefix_is_valid(name)) + return -EINVAL; + + if (streq(slice, "-.slice")) + subslice = strappend(name, ".slice"); + else { + char *e; + + assert_se(e = endswith(slice, ".slice")); + + subslice = new(char, (e - slice) + 1 + strlen(name) + 6 + 1); + if (!subslice) + return -ENOMEM; + + stpcpy(stpcpy(stpcpy(mempcpy(subslice, slice, e - slice), "-"), name), ".slice"); + } + + *ret = subslice; + return 0; +} + +bool slice_name_is_valid(const char *name) { + const char *p, *e; + bool dash = false; + + if (!unit_name_is_valid(name, UNIT_NAME_PLAIN)) + return false; + + if (streq(name, "-.slice")) + return true; + + e = endswith(name, ".slice"); + if (!e) + return false; + + for (p = name; p < e; p++) { + + if (*p == '-') { + + /* Don't allow initial dash */ + if (p == name) + return false; + + /* Don't allow multiple dashes */ + if (dash) + return false; + + dash = true; + } else + dash = false; + } + + /* Don't allow trailing hash */ + if (dash) + return false; + + return true; +} + +static const char* const unit_type_table[_UNIT_TYPE_MAX] = { + [UNIT_SERVICE] = "service", + [UNIT_SOCKET] = "socket", + [UNIT_BUSNAME] = "busname", + [UNIT_TARGET] = "target", + [UNIT_SNAPSHOT] = "snapshot", + [UNIT_DEVICE] = "device", + [UNIT_MOUNT] = "mount", + [UNIT_AUTOMOUNT] = "automount", + [UNIT_SWAP] = "swap", + [UNIT_TIMER] = "timer", + [UNIT_PATH] = "path", + [UNIT_SLICE] = "slice", + [UNIT_SCOPE] = "scope" +}; + +DEFINE_STRING_TABLE_LOOKUP(unit_type, UnitType); + +static const char* const unit_load_state_table[_UNIT_LOAD_STATE_MAX] = { + [UNIT_STUB] = "stub", + [UNIT_LOADED] = "loaded", + [UNIT_NOT_FOUND] = "not-found", + [UNIT_ERROR] = "error", + [UNIT_MERGED] = "merged", + [UNIT_MASKED] = "masked" +}; + +DEFINE_STRING_TABLE_LOOKUP(unit_load_state, UnitLoadState); + +static const char* const unit_dependency_table[_UNIT_DEPENDENCY_MAX] = { + [UNIT_REQUIRES] = "Requires", + [UNIT_REQUIRES_OVERRIDABLE] = "RequiresOverridable", + [UNIT_REQUISITE] = "Requisite", + [UNIT_REQUISITE_OVERRIDABLE] = "RequisiteOverridable", + [UNIT_WANTS] = "Wants", + [UNIT_BINDS_TO] = "BindsTo", + [UNIT_PART_OF] = "PartOf", + [UNIT_REQUIRED_BY] = "RequiredBy", + [UNIT_REQUIRED_BY_OVERRIDABLE] = "RequiredByOverridable", + [UNIT_REQUISITE_OF] = "RequisiteOf", + [UNIT_REQUISITE_OF_OVERRIDABLE] = "RequisiteOfOverridable", + [UNIT_WANTED_BY] = "WantedBy", + [UNIT_BOUND_BY] = "BoundBy", + [UNIT_CONSISTS_OF] = "ConsistsOf", + [UNIT_CONFLICTS] = "Conflicts", + [UNIT_CONFLICTED_BY] = "ConflictedBy", + [UNIT_BEFORE] = "Before", + [UNIT_AFTER] = "After", + [UNIT_ON_FAILURE] = "OnFailure", + [UNIT_TRIGGERS] = "Triggers", + [UNIT_TRIGGERED_BY] = "TriggeredBy", + [UNIT_PROPAGATES_RELOAD_TO] = "PropagatesReloadTo", + [UNIT_RELOAD_PROPAGATED_FROM] = "ReloadPropagatedFrom", + [UNIT_JOINS_NAMESPACE_OF] = "JoinsNamespaceOf", + [UNIT_REFERENCES] = "References", + [UNIT_REFERENCED_BY] = "ReferencedBy", +}; + +DEFINE_STRING_TABLE_LOOKUP(unit_dependency, UnitDependency); |