shaba/systemd
1
0
Fork 0
mirror of https://github.com/systemd/systemd.git synced 2025-02-03 17:47:28 +03:00
Code

id128: when taking user input for a 128bit ID, validate syntax

Browse Source 
Also, always accept both our simple hexdump syntax and UUID syntax.
This commit is contained in:
Lennart Poettering 2013-04-29 18:39:12 -03:00
parent 6886b0449d
commit aa96c6cb44
10 changed files with 167 additions and 64 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
TODO
View File

@ -26,9 +26,7 @@ Fedora 19:
Features:
* nss-myhostname: investigate whether there's any point in also
resolving localhost6, localhost.localdomain, ip6-localhost or any of
the other names often seen in /etc/hosts
* investigate endianess issues of UUID vs. GUID
* see if we can fix https://bugs.freedesktop.org/show_bug.cgi?id=63672
without dropping the location cache entirely.
@ -36,8 +34,6 @@ Features:
* dbus: when a unit failed to load (i.e. is in UNIT_ERROR state), we
should be able to safely try another attempt when the bus call LoadUnit() is invoked.
* for instanced unit drop-ins we should look in foo@bar.service.d/ as well as foo@.service.d/
* if pam_systemd is invoked by su from a process that is outside of a
any session we should probably just become a NOP, since that's
usually not a real user session but just some system code that just
@ -61,8 +57,6 @@ Features:
* make sure cg_pid_get_path() works properly for co-mounted controllers
* nspawn: ensure syntax of --uuid= argument is correct
* explicitly disallow changing the cgroup path of units in the
name=systemd hierarchy, unless it is outside of /system

17
man/sd_id128_to_string.xml
View File

@ -59,7 +59,7 @@
<funcprototype>
<funcdef>int <function>sd_id128_from_string</function></funcdef>
<paramdef>const char <parameter>s</parameter>[33], sd_id128_t* <parameter>ret</parameter></paramdef>
<paramdef>const char* <parameter>s</parameter>, sd_id128_t* <parameter>ret</parameter></paramdef>
</funcprototype>
</funcsynopsis>
@ -77,14 +77,19 @@
<para><function>sd_id128_from_string()</function>
implements the reverse operation: it takes a 33
character array with 32 hexadecimal digits
(terminated by NUL) and parses them back into an
128 bit ID returned in
<parameter>ret</parameter>.</para>
character string with 32 hexadecimal digits
(either lowercase or uppercase, terminated by NUL) and parses them back into an 128
bit ID returned in
<parameter>ret</parameter>. Alternatively, this call
can also parse a 37 character string with a 128bit ID
formatted as RFC UUID.</para>
<para>For more information about the
<literal>sd_id128_t</literal> type see
<citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
<citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Note
that these calls operate the same way on all
architectures, i.e. the results do not depend on
endianess.</para>
<para>When formatting a 128 bit ID into a string it is
often easier to use a format string for

40
src/core/load-dropin.c
View File

@ -31,7 +31,12 @@
#include "load-fragment.h"
#include "conf-files.h"
static int iterate_dir(Unit *u, const char *path, UnitDependency dependency, char ***strv) {
static int iterate_dir(
Unit *u,
const char *path,
UnitDependency dependency,
char ***strv) {
_cleanup_closedir_ DIR *d = NULL;
int r;
@ -86,7 +91,14 @@ static int iterate_dir(Unit *u, const char *path, UnitDependency dependency, cha
return 0;
}
static int process_dir(Unit *u, const char *unit_path, const char *name, const char *suffix, UnitDependency dependency, char ***strv) {
static int process_dir(
Unit *u,
const char *unit_path,
const char *name,
const char *suffix,
UnitDependency dependency,
char ***strv) {
int r;
char *path;
@ -97,7 +109,7 @@ static int process_dir(Unit *u, const char *unit_path, const char *name, const c
path = strjoin(unit_path, "/", name, suffix, NULL);
if (!path)
return -ENOMEM;
return log_oom();
if (u->manager->unit_path_cache &&
!set_get(u->manager->unit_path_cache, path))
@ -115,13 +127,13 @@ static int process_dir(Unit *u, const char *unit_path, const char *name, const c
template = unit_name_template(name);
if (!template)
return -ENOMEM;
return log_oom();
path = strjoin(unit_path, "/", template, suffix, NULL);
free(template);
if (!path)
return -ENOMEM;
return log_oom();
if (u->manager->unit_path_cache &&
!set_get(u->manager->unit_path_cache, path))
@ -138,10 +150,10 @@ static int process_dir(Unit *u, const char *unit_path, const char *name, const c
}
char **unit_find_dropin_paths(Unit *u) {
Iterator i;
char *t;
_cleanup_strv_free_ char **strv = NULL;
char **configs = NULL;
Iterator i;
char *t;
int r;
assert(u);
@ -157,14 +169,14 @@ char **unit_find_dropin_paths(Unit *u) {
}
}
if (!strv_isempty(strv)) {
r = conf_files_list_strv(&configs, ".conf", NULL, (const char**) strv);
if (r < 0) {
log_error("Failed to get list of configuration files: %s", strerror(-r));
strv_free(configs);
return NULL;
}
if (strv_isempty(strv))
return NULL;
r = conf_files_list_strv(&configs, ".conf", NULL, (const char**) strv);
if (r < 0) {
log_error("Failed to get list of configuration files: %s", strerror(-r));
strv_free(configs);
return NULL;
}
return configs;

30
src/core/machine-id-setup.c
View File

@ -72,16 +72,19 @@ static int generate(char id[34]) {
/* First, try reading the D-Bus machine id, unless it is a symlink */
fd = open("/var/lib/dbus/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
if (fd >= 0) {
k = loop_read(fd, id, 32, false);
k = loop_read(fd, id, 33, false);
close_nointr_nofail(fd);
if (k >= 32) {
id[32] = '\n';
id[33] = 0;
if (k == 33 && id[32] == '\n') {
log_info("Initializing machine ID from D-Bus machine ID.");
return 0;
id[32] = 0;
if (id128_is_valid(id)) {
id[32] = '\n';
id[33] = 0;
log_info("Initializing machine ID from D-Bus machine ID.");
return 0;
}
}
}
@ -113,7 +116,7 @@ static int generate(char id[34]) {
* $container_uuid the way libvirt/LXC does it */
r = detect_container(NULL);
if (r > 0) {
char *e;
_cleanup_free_ char *e = NULL;
r = getenv_for_pid(1, "container_uuid", &e);
if (r > 0) {
@ -121,12 +124,9 @@ static int generate(char id[34]) {
r = shorten_uuid(id, e);
if (r >= 0) {
log_info("Initializing machine ID from container UUID.");
free(e);
return 0;
}
}
free(e);
}
}
@ -183,8 +183,12 @@ int machine_id_setup(void) {
}
if (S_ISREG(st.st_mode))
if (loop_read(fd, id, 32, false) >= 32)
return 0;
if (loop_read(fd, id, 33, false) == 33 && id[32] == '\n') {
id[32] = 0;
if (id128_is_valid(id))
return 0;
}
/* Hmm, so, the id currently stored is not useful, then let's
* generate one */

61
src/libsystemd-id128/sd-id128.c
View File

@ -44,30 +44,50 @@ _public_ char *sd_id128_to_string(sd_id128_t id, char s[33]) {
return s;
}
_public_ int sd_id128_from_string(const char s[33], sd_id128_t *ret) {
unsigned n;
_public_ int sd_id128_from_string(const char s[], sd_id128_t *ret) {
unsigned n, i;
sd_id128_t t;
bool is_guid = false;
if (!s)
return -EINVAL;
if (!ret)
return -EINVAL;
for (n = 0; n < 16; n++) {
for (n = 0, i = 0; n < 16;) {
int a, b;
a = unhexchar(s[n*2]);
if (s[i] == '-') {
/* Is this a GUID? Then be nice, and skip over
* the dashes */
if (i == 8)
is_guid = true;
else if (i == 13 || i == 18 || i == 23) {
if (!is_guid)
return -EINVAL;
} else
return -EINVAL;
i++;
continue;
}
a = unhexchar(s[i++]);
if (a < 0)
return -EINVAL;
b = unhexchar(s[n*2+1]);
b = unhexchar(s[i++]);
if (b < 0)
return -EINVAL;
t.bytes[n] = (a << 4) | b;
t.bytes[n++] = (a << 4) | b;
}
if (s[32] != 0)
if (i != (is_guid ? 36 : 32))
return -EINVAL;
if (s[i] != 0)
return -EINVAL;
*ret = t;
@ -90,8 +110,8 @@ static sd_id128_t make_v4_uuid(sd_id128_t id) {
_public_ int sd_id128_get_machine(sd_id128_t *ret) {
static __thread sd_id128_t saved_machine_id;
static __thread bool saved_machine_id_valid = false;
int fd;
char buf[32];
_cleanup_close_ int fd = -1;
char buf[33];
ssize_t k;
unsigned j;
sd_id128_t t;
@ -108,13 +128,14 @@ _public_ int sd_id128_get_machine(sd_id128_t *ret) {
if (fd < 0)
return -errno;
k = loop_read(fd, buf, 32, false);
close_nointr_nofail(fd);
k = loop_read(fd, buf, 33, false);
if (k < 0)
return (int) k;
if (k < 32)
if (k != 33)
return -EIO;
if (buf[32] !='\n')
return -EIO;
for (j = 0; j < 16; j++) {
@ -139,7 +160,7 @@ _public_ int sd_id128_get_machine(sd_id128_t *ret) {
_public_ int sd_id128_get_boot(sd_id128_t *ret) {
static __thread sd_id128_t saved_boot_id;
static __thread bool saved_boot_id_valid = false;
int fd;
_cleanup_close_ int fd = -1;
char buf[36];
ssize_t k;
unsigned j;
@ -159,12 +180,10 @@ _public_ int sd_id128_get_boot(sd_id128_t *ret) {
return -errno;
k = loop_read(fd, buf, 36, false);
close_nointr_nofail(fd);
if (k < 0)
return (int) k;
if (k < 36)
if (k != 36)
return -EIO;
for (j = 0, p = buf; j < 16; j++) {
@ -195,9 +214,9 @@ _public_ int sd_id128_get_boot(sd_id128_t *ret) {
}
_public_ int sd_id128_randomize(sd_id128_t *ret) {
int fd;
ssize_t k;
_cleanup_close_ int fd = -1;
sd_id128_t t;
ssize_t k;
if (!ret)
return -EINVAL;
@ -207,12 +226,10 @@ _public_ int sd_id128_randomize(sd_id128_t *ret) {
return -errno;
k = loop_read(fd, &t, 16, false);
close_nointr_nofail(fd);
if (k < 0)
return (int) k;
if (k < 16)
if (k != 16)
return -EIO;
/* Turn this into a valid v4 UUID, to be nice. Note that we

5
src/nspawn/nspawn.c
View File

@ -222,6 +222,11 @@ static int parse_argv(int argc, char *argv[]) {
break;
case ARG_UUID:
if (!id128_is_valid(optarg)) {
log_error("Invalid UUID: %s", optarg);
return -EINVAL;
}
arg_uuid = optarg;
break;

41
src/shared/util.c
View File

@ -5854,3 +5854,44 @@ void* greedy_realloc(void **p, size_t *allocated, size_t need) {
*allocated = a;
return q;
}
bool id128_is_valid(const char *s) {
size_t i, l;
l = strlen(s);
if (l == 32) {
/* Simple formatted 128bit hex string */
for (i = 0; i < l; i++) {
char c = s[i];
if (!(c >= '0' && c <= '9') &&
!(c >= 'a' && c <= 'z') &&
!(c >= 'A' && c <= 'Z'))
return false;
}
} else if (l == 36) {
/* Formatted UUID */
for (i = 0; i < l; i++) {
char c = s[i];
if ((i == 8 || i == 13 || i == 18 || i == 23)) {
if (c != '-')
return false;
} else {
if (!(c >= '0' && c <= '9') &&
!(c >= 'a' && c <= 'z') &&
!(c >= 'A' && c <= 'Z'))
return false;
}
}
} else
return false;
return true;
}

2
src/shared/util.h
View File

@ -733,3 +733,5 @@ static inline void _reset_locale_(struct _locale_struct_ *s) {
} \
!_saved_locale_.quit; }) ; \
_saved_locale_.quit = true)
bool id128_is_valid(const char *s);

2
src/systemd/sd-id128.h
View File

@ -40,7 +40,7 @@ union sd_id128 {
char *sd_id128_to_string(sd_id128_t id, char s[33]);
int sd_id128_from_string(const char s[33], sd_id128_t *ret);
int sd_id128_from_string(const char *s, sd_id128_t *ret);
int sd_id128_randomize(sd_id128_t *ret);

25
src/test/test-id128.c
View File

@ -27,10 +27,13 @@
#include "macro.h"
#define ID128_WALDI SD_ID128_MAKE(01, 02, 03, 04, 05, 06, 07, 08, 09, 0a, 0b, 0c, 0d, 0e, 0f, 10)
#define STR_WALDI "0102030405060708090a0b0c0d0e0f10"
#define UUID_WALDI "01020304-0506-0708-090a-0b0c0d0e0f10"
int main(int argc, char *argv[]) {
sd_id128_t id, id2;
char t[33];
_cleanup_free_ char *b = NULL;
assert_se(sd_id128_randomize(&id) == 0);
printf("random: %s\n", sd_id128_to_string(id, t));
@ -45,8 +48,28 @@ int main(int argc, char *argv[]) {
printf("boot: %s\n", sd_id128_to_string(id, t));
printf("waldi: %s\n", sd_id128_to_string(ID128_WALDI, t));
assert_se(streq(t, STR_WALDI));
printf("waldi2: " SD_ID128_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(ID128_WALDI));
assert_se(asprintf(&b, SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL(ID128_WALDI)) == 32);
printf("waldi2: %s\n", b);
assert_se(streq(t, b));
assert_se(sd_id128_from_string(UUID_WALDI, &id) >= 0);
assert_se(sd_id128_equal(id, ID128_WALDI));
assert_se(sd_id128_from_string("", &id) < 0);
assert_se(sd_id128_from_string("01020304-0506-0708-090a-0b0c0d0e0f101", &id) < 0);
assert_se(sd_id128_from_string("01020304-0506-0708-090a-0b0c0d0e0f10-", &id) < 0);
assert_se(sd_id128_from_string("01020304-0506-0708-090a0b0c0d0e0f10", &id) < 0);
assert_se(sd_id128_from_string("010203040506-0708-090a-0b0c0d0e0f10", &id) < 0);
assert_se(id128_is_valid(STR_WALDI));
assert_se(id128_is_valid(UUID_WALDI));
assert_se(!id128_is_valid(""));
assert_se(!id128_is_valid("01020304-0506-0708-090a-0b0c0d0e0f101"));
assert_se(!id128_is_valid("01020304-0506-0708-090a-0b0c0d0e0f10-"));
assert_se(!id128_is_valid("01020304-0506-0708-090a0b0c0d0e0f10"));
assert_se(!id128_is_valid("010203040506-0708-090a-0b0c0d0e0f10"));
return 0;
}