env: considerably beef up environment cleaning logic

Now, actually check if the environment variable names and values used
are valid, before accepting them. With this in place are at some places
more rigid than POSIX, and less rigid at others. For example, this code
allows lower-case environment variables (which POSIX suggests not to
use), but it will not allow non-UTF8 variable values.

All in all this should be a good middle ground of what to allow and what
not to allow as environment variables.

(This also splits out all environment related calls into env-util.[ch])

1 files changed, 0 insertions, 243 deletions

diff --git a/src/shared/strv.c b/src/shared/strv.c
index fc6104ffea..ee0b71ece0 100644
--- a/src/shared/strv.c
+++ b/src/shared/strv.c
@@ -458,249 +458,6 @@ char **strv_remove_prefix(char **l, const char *s) {
         return l;
 }
 
-static int env_append(char **r, char ***k, char **a) {
-        assert(r);
-        assert(k);
-
-        if (!a)
-                return 0;
-
-        /* Add the entries of a to *k unless they already exist in *r
-         * in which case they are overridden instead. This assumes
-         * there is enough space in the r array. */
-
-        for (; *a; a++) {
-                char **j;
-                size_t n;
-
-                n = strcspn(*a, "=");
-
-                if ((*a)[n] == '=')
-                        n++;
-
-                for (j = r; j < *k; j++)
-                        if (strncmp(*j, *a, n) == 0)
-                                break;
-
-                if (j >= *k)
-                        (*k)++;
-                else
-                        free(*j);
-
-                *j = strdup(*a);
-                if (!*j)
-                        return -ENOMEM;
-        }
-
-        return 0;
-}
-
-char **strv_env_merge(unsigned n_lists, ...) {
-        size_t n = 0;
-        char **l, **k, **r;
-        va_list ap;
-        unsigned i;
-
-        /* 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);
-
-        r = new(char*, n+1);
-        if (!r)
-                return NULL;
-
-        k = r;
-
-        va_start(ap, n_lists);
-        for (i = 0; i < n_lists; i++) {
-                l = va_arg(ap, char**);
-                if (env_append(r, &k, l) < 0)
-                        goto fail;
-        }
-        va_end(ap);
-
-        *k = NULL;
-
-        return r;
-
-fail:
-        va_end(ap);
-        strv_free(r);
-
-        return NULL;
-}
-
-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 strncmp(t, pattern, l) == 0 && t[l] == '=';
-        }
-
-        return false;
-}
-
-char **strv_env_delete(char **x, unsigned 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) {
-                unsigned 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_set(char **x, const char *p) {
-
-        char **k, **r;
-        char* m[2] = { (char*) p, NULL };
-
-        /* Overrides the env var setting of p, returns a new copy */
-
-        r = new(char*, strv_length(x)+2);
-        if (!r)
-                return NULL;
-
-        k = r;
-        if (env_append(r, &k, x) < 0)
-                goto fail;
-
-        if (env_append(r, &k, m) < 0)
-                goto fail;
-
-        *k = NULL;
-
-        return r;
-
-fail:
-        strv_free(r);
-        return NULL;
-
-}
-
-char *strv_env_get_with_length(char **l, const char *name, size_t k) {
-        char **i;
-
-        assert(name);
-
-        STRV_FOREACH(i, l)
-                if (strncmp(*i, name, k) == 0 &&
-                    (*i)[k] == '=')
-                        return *i + k + 1;
-
-        return NULL;
-}
-
-char *strv_env_get(char **l, const char *name) {
-        return strv_env_get_with_length(l, name, strlen(name));
-}
-
-char **strv_env_clean(char **l) {
-        char **r, **ret;
-
-        for (r = ret = l; *l; l++) {
-                const char *equal;
-
-                equal = strchr(*l, '=');
-
-                if (equal && equal[1] == 0) {
-                        free(*l);
-                        continue;
-                }
-
-                *(r++) = *l;
-        }
-
-        *r = NULL;
-
-        return ret;
-}
-
 char **strv_parse_nulstr(const char *s, size_t l) {
         const char *p;
         unsigned c = 0, i = 0;