#include <errno.h>

#include <limits.h>

#include <stdarg.h>

#include <stdlib.h>

#include <unistd.h>

#include "alloc-util.h"

#include "env-util.h"

#include "errno-util.h"

#include "escape.h"

#include "extract-word.h"

#include "macro.h"

#include "parse-util.h"

#include "path-util.h"

#include "process-util.h"

#include "stdio-util.h"

#include "string-util.h"

#include "strv.h"

#include "utf8.h"

#define VALID_BASH_ENV_NAME_CHARS \

DIGITS LETTERS \

"_"

static bool env_name_is_valid_n(const char *e, size_t n) {

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

if (n > (size_t) sysconf(_SC_ARG_MAX) - 2)

return false;

for (const char *p = e; p < e + n; p++)

if (!strchr(VALID_BASH_ENV_NAME_CHARS, *p))

return false;

return true;

}

bool env_name_is_valid(const char *e) {

return env_name_is_valid_n(e, strlen_ptr(e));

}

bool env_value_is_valid(const char *e) {

if (!e)

return false;

if (!utf8_is_valid(e))

return false;

/* Note that variable *values* may contain control characters, in particular NL, TAB, BS, DEL, ESC…

/* POSIX says the overall size of the environment block cannot be > ARG_MAX, an individual assignment

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

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'

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(char **first, ...) {

_cleanup_strv_free_ char **merged = NULL;

char **k;

va_list ap;

/* Merges an arbitrary number of environment sets */

size_t n = strv_length(first);

va_start(ap, first);

for (;;) {

char **l;

l = va_arg(ap, char**);

if (l == POINTER_MAX)

break;

n += strv_length(l);

}

va_end(ap);

k = merged = new(char*, n + 1);

if (!merged)

return NULL;

merged[0] = NULL;

if (env_append(merged, &k, first) < 0)

return NULL;

va_start(ap, first);

for (;;) {

char **l;

l = va_arg(ap, char**);

if (l == POINTER_MAX)

break;

if (env_append(merged, &k, l) < 0) {

va_end(ap);

return NULL;

}

}

va_end(ap);

return TAKE_PTR(merged);

}

static bool env_match(const char *t, const char *pattern) {

assert(t);

assert(pattern);

/* pattern a matches string a

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

n = strv_length(x);

r = new(char*, n+1);

if (!r)

return NULL;

STRV_FOREACH(k, x) {

va_start(ap, n_lists);

for (size_t 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

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_consume(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

t = strchr(p, '=');

if (!t) {

free(p);

return -EINVAL;

}

name = strndupa_safe(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_consume(l, p);

if (r < 0)

return r;

return 1;

}

int strv_env_replace_strdup(char ***l, const char *assignment) {

/* Like strv_env_replace_consume(), but copies the argument. */

char *p = strdup(assignment);

if (!p)

return -ENOMEM;

return strv_env_replace_consume(l, p);

}

int strv_env_replace_strdup_passthrough(char ***l, const char *assignment) {

/* Like strv_env_replace_strdup(), but pulls the variable from the environment of

char *p;

if (strchr(assignment, '=')) {

if (!env_assignment_is_valid(assignment))

return -EINVAL;

p = strdup(assignment);

} else {

if (!env_name_is_valid(assignment))

return -EINVAL;

/* If we can't find the variable in our environment, we will use

p = strjoin(assignment, "=", secure_getenv(assignment));

}

if (!p)

return -ENOMEM;

return strv_env_replace_consume(l, p);

}

int strv_env_assign(char ***l, const char *key, const char *value) {

if (!env_name_is_valid(key))

return -EINVAL;

/* NULL removes assignment, "" creates an empty assignment. */

if (!value) {

strv_env_unset(*l, key);

return 0;

}

char *p = strjoin(key, "=", value);

if (!p)

return -ENOMEM;

return strv_env_replace_consume(l, p);

}

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_safe(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_pairs_get(char **l, const char *name) {

char **key, **value, *result = NULL;

assert(name);

STRV_FOREACH_PAIR(key, value, l)

if (streq(*key, name))

result = *value;

return result;

}

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 = NULL; /* test_value is initialized to appease gcc */

char *k;

_cleanup_free_ char *r = NULL;

size_t i, len = 0; /* len is initialized to appease gcc */

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_BASH_ENV_NAME_CHARS, *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);

if (!strextend(&r, t))

return NULL;

word = e+1;

state = WORD;

nest--;

} else if (*e == ':') {

if (flags & REPLACE_ENV_ALLOW_EXTENDED) {

len = e - word - 2;

state = TEST;

} else

/* Treat this as unsupported syntax, i.e. do no replacement */

state = WORD;

}

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);

if (!strextend(&r, t))

return NULL;

word = e+1;

state = WORD;

}

break;

case VARIABLE_RAW:

assert(flags & REPLACE_ENV_ALLOW_BRACELESS);

if (!strchr(VALID_BASH_ENV_NAME_CHARS, *e)) {

const char *t;

t = strv_env_get_n(env, word+1, e-word-1, flags);

if (!strextend(&r, t))

return NULL;

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;

}

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);

}

int set_unset_env(const char *name, const char *value, bool overwrite) {

assert(name);

if (value)

return RET_NERRNO(setenv(name, value, overwrite));

return RET_NERRNO(unsetenv(name));

}

int putenv_dup(const char *assignment, bool override) {

const char *e, *n;

e = strchr(assignment, '=');

if (!e)

return -EINVAL;

n = strndupa_safe(assignment, e - assignment);

/* This is like putenv(), but uses setenv() so that our memory doesn't become part of environ[]. */

return RET_NERRNO(setenv(n, e + 1, override));

}

int setenv_systemd_exec_pid(bool update_only) {

char str[DECIMAL_STR_MAX(pid_t)];

const char *e;

/* Update $SYSTEMD_EXEC_PID=pid except when '*' is set for the variable. */

e = secure_getenv("SYSTEMD_EXEC_PID");

if (!e && update_only)

return 0;

if (streq_ptr(e, "*"))

return 0;

xsprintf(str, PID_FMT, getpid_cached());

if (setenv("SYSTEMD_EXEC_PID", str, 1) < 0)

return -errno;

return 1;

}

int getenv_path_list(const char *name, char ***ret_paths) {

_cleanup_strv_free_ char **l = NULL;

const char *e;

char **p;

int r;

assert(name);

assert(ret_paths);

e = secure_getenv(name);

if (!e)

return -ENXIO;

r = strv_split_full(&l, e, ":", EXTRACT_DONT_COALESCE_SEPARATORS);

if (r < 0)

return log_debug_errno(r, "Failed to parse $%s: %m", name);

STRV_FOREACH(p, l) {

if (!path_is_absolute(*p))

return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),

"Path '%s' is not absolute, refusing.", *p);

if (!path_is_normalized(*p))

return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),

"Path '%s' is not normalized, refusing.", *p);

if (path_equal(*p, "/"))

return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),

"Path '%s' is the root fs, refusing.", *p);

}

if (strv_isempty(l))

return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),

"No paths specified, refusing.");

*ret_paths = TAKE_PTR(l);

return 1;

}

int unsetenv_erase(const char *name) {

char *p;

assert(name);

p = getenv(name);

if (!p)

return 0;

string_erase(p);

if (unsetenv(name) < 0)

return -errno;

return 1;

}