/* SPDX-License-Identifier: LGPL-2.1+ */
#include "nm-sd-adapt-shared.h"
#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <stdlib.h>
#include <unistd.h>
#include "alloc-util.h"
#include "env-util.h"
#include "escape.h"
#include "extract-word.h"
#include "macro.h"
#include "parse-util.h"
#include "string-util.h"
#include "strv.h"
#include "utf8.h"
#if 0 /* NM_IGNORED */
#define VALID_CHARS_ENV_NAME \
DIGITS LETTERS \
"_"
static bool env_name_is_valid_n(const char *e, size_t n) {
const char *p;
if (!e)
return false;
if (n <= 0)
return false;
if (e[0] >= '0' && e[0] <= '9')
return false;
/* POSIX says the overall size of the environment block cannot
* be > ARG_MAX, an individual assignment hence cannot be
* either. Discounting the equal sign and trailing NUL this
* hence leaves ARG_MAX-2 as longest possible variable
* name. */
if (n > (size_t) sysconf(_SC_ARG_MAX) - 2)
return false;
for (p = e; p < e + n; p++)
if (!strchr(VALID_CHARS_ENV_NAME, *p))
return false;
return true;
}
bool env_name_is_valid(const char *e) {
if (!e)
return false;
return env_name_is_valid_n(e, strlen(e));
}
bool env_value_is_valid(const char *e) {
if (!e)
return false;
if (!utf8_is_valid(e))
return false;
/* bash allows tabs and newlines in environment variables, and so
* should we */
if (string_has_cc(e, "\t\n"))
return false;
/* POSIX says the overall size of the environment block cannot
* be > ARG_MAX, an individual assignment hence cannot be
* either. Discounting the shortest possible variable name of
* length 1, the equal sign and trailing NUL this hence leaves
* ARG_MAX-3 as longest possible variable value. */
if (strlen(e) > sc_arg_max() - 3)
return false;
return true;
}
bool env_assignment_is_valid(const char *e) {
const char *eq;
eq = strchr(e, '=');
if (!eq)
return false;
if (!env_name_is_valid_n(e, eq - e))
return false;
if (!env_value_is_valid(eq + 1))
return false;
/* POSIX says the overall size of the environment block cannot
* be > ARG_MAX, hence the individual variable assignments
* cannot be either, but let's leave room for one trailing NUL
* byte. */
if (strlen(e) > sc_arg_max() - 1)
return false;
return true;
}
bool strv_env_is_valid(char **e) {
char **p, **q;
STRV_FOREACH(p, e) {
size_t k;
if (!env_assignment_is_valid(*p))
return false;
/* Check if there are duplicate assignments */
k = strcspn(*p, "=");
STRV_FOREACH(q, p + 1)
if (strneq(*p, *q, k) && (*q)[k] == '=')
return false;
}
return true;
}
bool strv_env_name_is_valid(char **l) {
char **p;
STRV_FOREACH(p, l) {
if (!env_name_is_valid(*p))
return false;
if (strv_contains(p + 1, *p))
return false;
}
return true;
}
bool strv_env_name_or_assignment_is_valid(char **l) {
char **p;
STRV_FOREACH(p, l) {
if (!env_assignment_is_valid(*p) && !env_name_is_valid(*p))
return false;
if (strv_contains(p + 1, *p))
return false;
}
return true;
}
static int env_append(char **r, char ***k, char **a) {
assert(r);
assert(k);
assert(*k >= r);
if (!a)
return 0;
/* Expects the following arguments: 'r' shall point to the beginning of an strv we are going to append to, 'k'
* to a pointer pointing to the NULL entry at the end of the same array. 'a' shall point to another strv.
*
* This call adds every entry of 'a' to 'r', either overriding an existing matching entry, or appending to it.
*
* This call assumes 'r' has enough pre-allocated space to grow by all of 'a''s items. */
for (; *a; a++) {
char **j, *c;
size_t n;
n = strcspn(*a, "=");
if ((*a)[n] == '=')
n++;
for (j = r; j < *k; j++)
if (strneq(*j, *a, n))
break;
c = strdup(*a);
if (!c)
return -ENOMEM;
if (j >= *k) { /* Append to the end? */
(*k)[0] = c;
(*k)[1] = NULL;
(*k)++;
} else
free_and_replace(*j, c); /* Override existing item */
}
return 0;
}
char **strv_env_merge(size_t n_lists, ...) {
_cleanup_strv_free_ char **ret = NULL;
size_t n = 0, i;
char **l, **k;
va_list ap;
/* Merges an arbitrary number of environment sets */
va_start(ap, n_lists);
for (i = 0; i < n_lists; i++) {
l = va_arg(ap, char**);
n += strv_length(l);
}
va_end(ap);
ret = new(char*, n+1);
if (!ret)
return NULL;
*ret = NULL;
k = ret;
va_start(ap, n_lists);
for (i = 0; i < n_lists; i++) {
l = va_arg(ap, char**);
if (env_append(ret, &k, l) < 0) {
va_end(ap);
return NULL;
}
}
va_end(ap);
return TAKE_PTR(ret);
}
static bool env_match(const char *t, const char *pattern) {
assert(t);
assert(pattern);
/* pattern a matches string a
* a matches a=
* a matches a=b
* a= matches a=
* a=b matches a=b
* a= does not match a
* a=b does not match a=
* a=b does not match a
* a=b does not match a=c */
if (streq(t, pattern))
return true;
if (!strchr(pattern, '=')) {
size_t l = strlen(pattern);
return strneq(t, pattern, l) && t[l] == '=';
}
return false;
}
static bool env_entry_has_name(const char *entry, const char *name) {
const char *t;
assert(entry);
assert(name);
t = startswith(entry, name);
if (!t)
return false;
return *t == '=';
}
char **strv_env_delete(char **x, size_t n_lists, ...) {
size_t n, i = 0;
char **k, **r;
va_list ap;
/* Deletes every entry from x that is mentioned in the other
* string lists */
n = strv_length(x);
r = new(char*, n+1);
if (!r)
return NULL;
STRV_FOREACH(k, x) {
size_t v;
va_start(ap, n_lists);
for (v = 0; v < n_lists; v++) {
char **l, **j;
l = va_arg(ap, char**);
STRV_FOREACH(j, l)
if (env_match(*k, *j))
goto skip;
}
va_end(ap);
r[i] = strdup(*k);
if (!r[i]) {
strv_free(r);
return NULL;
}
i++;
continue;
skip:
va_end(ap);
}
r[i] = NULL;
assert(i <= n);
return r;
}
char **strv_env_unset(char **l, const char *p) {
char **f, **t;
if (!l)
return NULL;
assert(p);
/* Drops every occurrence of the env var setting p in the
* string list. Edits in-place. */
for (f = t = l; *f; f++) {
if (env_match(*f, p)) {
free(*f);
continue;
}
*(t++) = *f;
}
*t = NULL;
return l;
}
char **strv_env_unset_many(char **l, ...) {
char **f, **t;
if (!l)
return NULL;
/* Like strv_env_unset() but applies many at once. Edits in-place. */
for (f = t = l; *f; f++) {
bool found = false;
const char *p;
va_list ap;
va_start(ap, l);
while ((p = va_arg(ap, const char*))) {
if (env_match(*f, p)) {
found = true;
break;
}
}
va_end(ap);
if (found) {
free(*f);
continue;
}
*(t++) = *f;
}
*t = NULL;
return l;
}
int strv_env_replace(char ***l, char *p) {
const char *t, *name;
char **f;
int r;
assert(p);
/* Replace first occurrence of the env var or add a new one in the string list. Drop other occurrences. Edits
* in-place. Does not copy p. p must be a valid key=value assignment.
*/
t = strchr(p, '=');
if (!t)
return -EINVAL;
name = strndupa(p, t - p);
STRV_FOREACH(f, *l)
if (env_entry_has_name(*f, name)) {
free_and_replace(*f, p);
strv_env_unset(f + 1, *f);
return 0;
}
/* We didn't find a match, we need to append p or create a new strv */
r = strv_push(l, p);
if (r < 0)
return r;
return 1;
}
char **strv_env_set(char **x, const char *p) {
_cleanup_strv_free_ char **ret = NULL;
size_t n, m;
char **k;
/* Overrides the env var setting of p, returns a new copy */
n = strv_length(x);
m = n + 2;
if (m < n) /* overflow? */
return NULL;
ret = new(char*, m);
if (!ret)
return NULL;
*ret = NULL;
k = ret;
if (env_append(ret, &k, x) < 0)
return NULL;
if (env_append(ret, &k, STRV_MAKE(p)) < 0)
return NULL;
return TAKE_PTR(ret);
}
char *strv_env_get_n(char **l, const char *name, size_t k, unsigned flags) {
char **i;
assert(name);
if (k <= 0)
return NULL;
STRV_FOREACH_BACKWARDS(i, l)
if (strneq(*i, name, k) &&
(*i)[k] == '=')
return *i + k + 1;
if (flags & REPLACE_ENV_USE_ENVIRONMENT) {
const char *t;
t = strndupa(name, k);
return getenv(t);
};
return NULL;
}
char *strv_env_get(char **l, const char *name) {
assert(name);
return strv_env_get_n(l, name, strlen(name), 0);
}
char **strv_env_clean_with_callback(char **e, void (*invalid_callback)(const char *p, void *userdata), void *userdata) {
char **p, **q;
int k = 0;
STRV_FOREACH(p, e) {
size_t n;
bool duplicate = false;
if (!env_assignment_is_valid(*p)) {
if (invalid_callback)
invalid_callback(*p, userdata);
free(*p);
continue;
}
n = strcspn(*p, "=");
STRV_FOREACH(q, p + 1)
if (strneq(*p, *q, n) && (*q)[n] == '=') {
duplicate = true;
break;
}
if (duplicate) {
free(*p);
continue;
}
e[k++] = *p;
}
if (e)
e[k] = NULL;
return e;
}
char *replace_env_n(const char *format, size_t n, char **env, unsigned flags) {
enum {
WORD,
CURLY,
VARIABLE,
VARIABLE_RAW,
TEST,
DEFAULT_VALUE,
ALTERNATE_VALUE,
} state = WORD;
const char *e, *word = format, *test_value;
char *k;
_cleanup_free_ char *r = NULL;
size_t i, len;
int nest = 0;
assert(format);
for (e = format, i = 0; *e && i < n; e ++, i ++)
switch (state) {
case WORD:
if (*e == '$')
state = CURLY;
break;
case CURLY:
if (*e == '{') {
k = strnappend(r, word, e-word-1);
if (!k)
return NULL;
free_and_replace(r, k);
word = e-1;
state = VARIABLE;
nest++;
} else if (*e == '$') {
k = strnappend(r, word, e-word);
if (!k)
return NULL;
free_and_replace(r, k);
word = e+1;
state = WORD;
} else if (flags & REPLACE_ENV_ALLOW_BRACELESS && strchr(VALID_CHARS_ENV_NAME, *e)) {
k = strnappend(r, word, e-word-1);
if (!k)
return NULL;
free_and_replace(r, k);
word = e-1;
state = VARIABLE_RAW;
} else
state = WORD;
break;
case VARIABLE:
if (*e == '}') {
const char *t;
t = strv_env_get_n(env, word+2, e-word-2, flags);
k = strjoin(r, t);
if (!k)
return NULL;
free_and_replace(r, k);
word = e+1;
state = WORD;
} else if (*e == ':') {
if (!(flags & REPLACE_ENV_ALLOW_EXTENDED))
/* Treat this as unsupported syntax, i.e. do no replacement */
state = WORD;
else {
len = e-word-2;
state = TEST;
}
}
break;
case TEST:
if (*e == '-')
state = DEFAULT_VALUE;
else if (*e == '+')
state = ALTERNATE_VALUE;
else {
state = WORD;
break;
}
test_value = e+1;
break;
case DEFAULT_VALUE: /* fall through */
case ALTERNATE_VALUE:
assert(flags & REPLACE_ENV_ALLOW_EXTENDED);
if (*e == '{') {
nest++;
break;
}
if (*e != '}')
break;
nest--;
if (nest == 0) {
const char *t;
_cleanup_free_ char *v = NULL;
t = strv_env_get_n(env, word+2, len, flags);
if (t && state == ALTERNATE_VALUE)
t = v = replace_env_n(test_value, e-test_value, env, flags);
else if (!t && state == DEFAULT_VALUE)
t = v = replace_env_n(test_value, e-test_value, env, flags);
k = strjoin(r, t);
if (!k)
return NULL;
free_and_replace(r, k);
word = e+1;
state = WORD;
}
break;
case VARIABLE_RAW:
assert(flags & REPLACE_ENV_ALLOW_BRACELESS);
if (!strchr(VALID_CHARS_ENV_NAME, *e)) {
const char *t;
t = strv_env_get_n(env, word+1, e-word-1, flags);
k = strjoin(r, t);
if (!k)
return NULL;
free_and_replace(r, k);
word = e--;
i--;
state = WORD;
}
break;
}
if (state == VARIABLE_RAW) {
const char *t;
assert(flags & REPLACE_ENV_ALLOW_BRACELESS);
t = strv_env_get_n(env, word+1, e-word-1, flags);
return strjoin(r, t);
} else
return strnappend(r, word, e-word);
}
char **replace_env_argv(char **argv, char **env) {
char **ret, **i;
size_t k = 0, l = 0;
l = strv_length(argv);
ret = new(char*, l+1);
if (!ret)
return NULL;
STRV_FOREACH(i, argv) {
/* If $FOO appears as single word, replace it by the split up variable */
if ((*i)[0] == '$' && !IN_SET((*i)[1], '{', '$')) {
char *e;
char **w, **m = NULL;
size_t q;
e = strv_env_get(env, *i+1);
if (e) {
int r;
r = strv_split_full(&m, e, WHITESPACE, EXTRACT_RELAX|EXTRACT_UNQUOTE);
if (r < 0) {
ret[k] = NULL;
strv_free(ret);
return NULL;
}
} else
m = NULL;
q = strv_length(m);
l = l + q - 1;
w = reallocarray(ret, l + 1, sizeof(char *));
if (!w) {
ret[k] = NULL;
strv_free(ret);
strv_free(m);
return NULL;
}
ret = w;
if (m) {
memcpy(ret + k, m, q * sizeof(char*));
free(m);
}
k += q;
continue;
}
/* If ${FOO} appears as part of a word, replace it by the variable as-is */
ret[k] = replace_env(*i, env, 0);
if (!ret[k]) {
strv_free(ret);
return NULL;
}
k++;
}
ret[k] = NULL;
return ret;
}
#endif /* NM_IGNORED */
int getenv_bool(const char *p) {
const char *e;
e = getenv(p);
if (!e)
return -ENXIO;
return parse_boolean(e);
}
int getenv_bool_secure(const char *p) {
const char *e;
e = secure_getenv(p);
if (!e)
return -ENXIO;
return parse_boolean(e);
}