nspawn: moved nspawn-creds.[ch] to shared/machine-credential.[ch]

This was done in order to allow sharing of this code between
systemd-nspawn and systemd-vmspawn.

src/shared/machine-credential.c

@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "alloc-util.h"
+#include "creds-util.h"
+#include "escape.h"
+#include "extract-word.h"
+#include "fileio.h"
+#include "macro.h"
+#include "memory-util.h"
+#include "machine-credential.h"
+#include "path-util.h"
+#include "string-util-fundamental.h"
+
+static void machine_credential_done(MachineCredential *cred) {
+        assert(cred);
+
+        cred->id = mfree(cred->id);
+        cred->data = erase_and_free(cred->data);
+        cred->size = 0;
+}
+
+void machine_credential_free_all(MachineCredential *creds, size_t n) {
+        assert(creds || n == 0);
+
+        FOREACH_ARRAY(cred, creds, n)
+                machine_credential_done(cred);
+
+        free(creds);
+}
+
+int machine_credential_set(MachineCredential **credentials, size_t *n_credentials, const char *cred_string) {
+        _cleanup_free_ char *word = NULL, *data = NULL;
+        MachineCredential *creds = *ASSERT_PTR(credentials);
+        ssize_t l;
+        size_t n_creds = *ASSERT_PTR(n_credentials);
+        int r;
+        const char *p = ASSERT_PTR(cred_string);
+
+        assert(creds || n_creds == 0);
+
+        r = extract_first_word(&p, &word, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r == -ENOMEM)
+                return r;
+        if (r < 0)
+                return log_error_errno(r, "Failed to parse --set-credential= parameter: %m");
+        if (r == 0 || !p)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Missing value for --set-credential=: %s", cred_string);
+
+        if (!credential_name_valid(word))
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "MachineCredential name is not valid: %s", word);
+
+        FOREACH_ARRAY(cred, creds, n_creds)
+                if (streq(cred->id, word))
+                        return log_error_errno(SYNTHETIC_ERRNO(EEXIST), "Duplicate credential '%s', refusing.", word);
+
+        l = cunescape(p, UNESCAPE_ACCEPT_NUL, &data);
+        if (l < 0)
+                return log_error_errno(l, "Failed to unescape credential data: %s", p);
+
+        GREEDY_REALLOC(creds, n_creds + 1);
+        if (!creds)
+                return -ENOMEM;
+
+        creds[n_creds++] = (MachineCredential) {
+                .id = TAKE_PTR(word),
+                .data = TAKE_PTR(data),
+                .size = l,
+        };
+
+        *credentials = creds;
+        *n_credentials = n_creds;
+
+        return 0;
+}
+
+int machine_credential_load(MachineCredential **credentials, size_t *n_credentials, const char *cred_path) {
+        ReadFullFileFlags flags = READ_FULL_FILE_SECURE;
+        _cleanup_(erase_and_freep) char *data = NULL;
+        _cleanup_free_ char *word = NULL, *j = NULL;
+        MachineCredential *creds = *ASSERT_PTR(credentials);
+        size_t size, n_creds = *ASSERT_PTR(n_credentials);
+        int r;
+        const char *p = ASSERT_PTR(cred_path);
+
+        assert(creds || n_creds == 0);
+
+        r = extract_first_word(&p, &word, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r == -ENOMEM)
+                return -ENOMEM;
+        if (r < 0)
+                return log_error_errno(r, "Failed to parse --load-credential= parameter: %m");
+        if (r == 0 || !p)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Missing value for --load-credential=: %s", cred_path);
+
+        if (!credential_name_valid(word))
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "MachineCredential name is not valid: %s", word);
+
+        FOREACH_ARRAY(cred, creds, n_creds)
+                if (streq(cred->id, word))
+                        return log_error_errno(SYNTHETIC_ERRNO(EEXIST), "Duplicate credential '%s', refusing.", word);
+
+        if (path_is_absolute(p))
+                flags |= READ_FULL_FILE_CONNECT_SOCKET;
+        else {
+                const char *e;
+
+                r = get_credentials_dir(&e);
+                if (r < 0)
+                        return log_error_errno(r, "MachineCredential not available (no credentials passed at all): %s", word);
+
+                j = path_join(e, p);
+                if (!j)
+                        return -ENOMEM;
+        }
+
+        r = read_full_file_full(AT_FDCWD, j ?: p, UINT64_MAX, SIZE_MAX,
+                                flags,
+                                NULL,
+                                &data, &size);
+        if (r < 0)
+                return log_error_errno(r, "Failed to read credential '%s': %m", j ?: p);
+
+        GREEDY_REALLOC(creds, n_creds + 1);
+        if (!creds)
+                return -ENOMEM;
+
+        creds[n_creds++] = (MachineCredential) {
+                .id = TAKE_PTR(word),
+                .data = TAKE_PTR(data),
+                .size = size,
+        };
+
+        *credentials = creds;
+        *n_credentials = n_creds;
+
+        return 0;
+}

src/shared/machine-credential.h

@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <sys/types.h>
+
+typedef struct MachineCredential {
+        char *id;
+        void *data;
+        size_t size;
+} MachineCredential;
+
+void machine_credential_free_all(MachineCredential *creds, size_t n);
+int machine_credential_set(MachineCredential **credentials, size_t *n_credentials, const char *cred_string);
+int machine_credential_load(MachineCredential **credentials, size_t *n_credentials, const char *cred_path);

src/shared/meson.build

@@ -111,6 +111,7 @@ shared_sources = files(
         'loop-util.c',
         'loopback-setup.c',
         'lsm-util.c',
+        'machine-credential.c',
         'machine-id-setup.c',
         'machine-pool.c',
         'macvlan-util.c',