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-rw-r--r--misc/e4crypt.c893
1 files changed, 893 insertions, 0 deletions
diff --git a/misc/e4crypt.c b/misc/e4crypt.c
new file mode 100644
index 0000000..67d25d8
--- /dev/null
+++ b/misc/e4crypt.c
@@ -0,0 +1,893 @@
+/*
+ * e4crypt.c - ext4 encryption management utility
+ *
+ * Copyright (c) 2014 Google, Inc.
+ * SHA512 implementation from libtomcrypt.
+ *
+ * Authors: Michael Halcrow <mhalcrow@google.com>,
+ * Ildar Muslukhov <ildarm@google.com>
+ */
+
+#ifndef _LARGEFILE_SOURCE
+#define _LARGEFILE_SOURCE
+#endif
+
+#ifndef _LARGEFILE64_SOURCE
+#define _LARGEFILE64_SOURCE
+#endif
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include "config.h"
+#include <assert.h>
+#include <errno.h>
+#include <getopt.h>
+#include <dirent.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <mntent.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <termios.h>
+#include <unistd.h>
+#include <signal.h>
+#if !defined(HAVE_ADD_KEY) || !defined(HAVE_KEYCTL)
+#include <sys/syscall.h>
+#endif
+#ifdef HAVE_SYS_KEY_H
+#include <sys/key.h>
+#endif
+
+#include "ext2fs/ext2_fs.h"
+#include "ext2fs/ext2fs.h"
+#include "uuid/uuid.h"
+
+/* special process keyring shortcut IDs */
+#define KEY_SPEC_THREAD_KEYRING -1
+#define KEY_SPEC_PROCESS_KEYRING -2
+#define KEY_SPEC_SESSION_KEYRING -3
+#define KEY_SPEC_USER_KEYRING -4
+#define KEY_SPEC_USER_SESSION_KEYRING -5
+#define KEY_SPEC_GROUP_KEYRING -6
+
+#define KEYCTL_GET_KEYRING_ID 0
+#define KEYCTL_JOIN_SESSION_KEYRING 1
+#define KEYCTL_DESCRIBE 6
+#define KEYCTL_SEARCH 10
+#define KEYCTL_SESSION_TO_PARENT 18
+
+typedef __s32 key_serial_t;
+
+#define EXT4_KEY_REF_STR_BUF_SIZE ((EXT4_KEY_DESCRIPTOR_SIZE * 2) + 1)
+
+#ifndef EXT4_IOC_GET_ENCRYPTION_PWSALT
+#define EXT4_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
+#endif
+
+#define OPT_VERBOSE 0x0001
+#define OPT_QUIET 0x0002
+
+int options;
+
+#ifndef HAVE_KEYCTL
+static long keyctl(int cmd, ...)
+{
+ va_list va;
+ unsigned long arg2, arg3, arg4, arg5;
+
+ va_start(va, cmd);
+ arg2 = va_arg(va, unsigned long);
+ arg3 = va_arg(va, unsigned long);
+ arg4 = va_arg(va, unsigned long);
+ arg5 = va_arg(va, unsigned long);
+ va_end(va);
+ return syscall(__NR_keyctl, cmd, arg2, arg3, arg4, arg5);
+}
+#endif
+
+#ifndef HAVE_ADD_KEY
+static key_serial_t add_key(const char *type, const char *description,
+ const void *payload, size_t plen,
+ key_serial_t keyring)
+{
+ return syscall(__NR_add_key, type, description, payload,
+ plen, keyring);
+}
+#endif
+
+static const unsigned char *hexchars = (const unsigned char *) "0123456789abcdef";
+static const size_t hexchars_size = 16;
+
+#define SHA512_LENGTH 64
+#define EXT2FS_KEY_TYPE_LOGON "logon"
+#define EXT2FS_KEY_DESC_PREFIX "ext4:"
+#define EXT2FS_KEY_DESC_PREFIX_SIZE 5
+
+#define EXT4_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct ext4_encryption_policy)
+#define EXT4_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct ext4_encryption_policy)
+
+static int int_log2(int arg)
+{
+ int l = 0;
+
+ arg >>= 1;
+ while (arg) {
+ l++;
+ arg >>= 1;
+ }
+ return l;
+}
+
+static void validate_paths(int argc, char *argv[], int path_start_index)
+{
+ int x;
+ int valid = 1;
+ struct stat st;
+
+ for (x = path_start_index; x < argc; x++) {
+ int ret = access(argv[x], W_OK);
+ if (ret) {
+ invalid:
+ perror(argv[x]);
+ valid = 0;
+ continue;
+ }
+ ret = stat(argv[x], &st);
+ if (ret < 0)
+ goto invalid;
+ if (!S_ISDIR(st.st_mode)) {
+ fprintf(stderr, "%s is not a directory\n", argv[x]);
+ goto invalid;
+ }
+ }
+ if (!valid)
+ exit(1);
+}
+
+static int hex2byte(const char *hex, size_t hex_size, unsigned char *bytes,
+ size_t bytes_size)
+{
+ size_t x;
+ unsigned char *h, *l;
+
+ if (hex_size % 2)
+ return -EINVAL;
+ for (x = 0; x < hex_size; x += 2) {
+ h = memchr(hexchars, hex[x], hexchars_size);
+ if (!h)
+ return -EINVAL;
+ l = memchr(hexchars, hex[x + 1], hexchars_size);
+ if (!l)
+ return -EINVAL;
+ if ((x >> 1) >= bytes_size)
+ return -EINVAL;
+ bytes[x >> 1] = (((unsigned char)(h - hexchars) << 4) +
+ (unsigned char)(l - hexchars));
+ }
+ return 0;
+}
+
+/*
+ * Salt handling
+ */
+struct salt {
+ unsigned char *salt;
+ char key_ref_str[EXT4_KEY_REF_STR_BUF_SIZE];
+ unsigned char key_desc[EXT4_KEY_DESCRIPTOR_SIZE];
+ unsigned char key[EXT4_MAX_KEY_SIZE];
+ size_t salt_len;
+};
+struct salt *salt_list;
+unsigned num_salt;
+unsigned max_salt;
+char in_passphrase[EXT4_MAX_PASSPHRASE_SIZE];
+
+static struct salt *find_by_salt(unsigned char *salt, size_t salt_len)
+{
+ unsigned int i;
+ struct salt *p;
+
+ for (i = 0, p = salt_list; i < num_salt; i++, p++)
+ if ((p->salt_len == salt_len) &&
+ !memcmp(p->salt, salt, salt_len))
+ return p;
+ return NULL;
+}
+
+static void add_salt(unsigned char *salt, size_t salt_len)
+{
+ if (find_by_salt(salt, salt_len))
+ return;
+ if (num_salt >= max_salt) {
+ max_salt = num_salt + 10;
+ salt_list = realloc(salt_list, max_salt * sizeof(struct salt));
+ if (!salt_list) {
+ fprintf(stderr, "Couldn't allocate salt list\n");
+ exit(1);
+ }
+ }
+ salt_list[num_salt].salt = salt;
+ salt_list[num_salt].salt_len = salt_len;
+ num_salt++;
+}
+
+static void clear_secrets(void)
+{
+ if (salt_list) {
+ memset(salt_list, 0, sizeof(struct salt) * max_salt);
+ free(salt_list);
+ salt_list = NULL;
+ }
+ memset(in_passphrase, 0, sizeof(in_passphrase));
+}
+
+static void die_signal_handler(int signum EXT2FS_ATTR((unused)),
+ siginfo_t *siginfo EXT2FS_ATTR((unused)),
+ void *context EXT2FS_ATTR((unused)))
+{
+ clear_secrets();
+ exit(-1);
+}
+
+static void sigcatcher_setup(void)
+{
+ struct sigaction sa;
+
+ memset(&sa, 0, sizeof(struct sigaction));
+ sa.sa_sigaction = die_signal_handler;
+ sa.sa_flags = SA_SIGINFO;
+
+ sigaction(SIGHUP, &sa, 0);
+ sigaction(SIGINT, &sa, 0);
+ sigaction(SIGQUIT, &sa, 0);
+ sigaction(SIGFPE, &sa, 0);
+ sigaction(SIGILL, &sa, 0);
+ sigaction(SIGBUS, &sa, 0);
+ sigaction(SIGSEGV, &sa, 0);
+ sigaction(SIGABRT, &sa, 0);
+ sigaction(SIGPIPE, &sa, 0);
+ sigaction(SIGALRM, &sa, 0);
+ sigaction(SIGTERM, &sa, 0);
+ sigaction(SIGUSR1, &sa, 0);
+ sigaction(SIGUSR2, &sa, 0);
+ sigaction(SIGPOLL, &sa, 0);
+ sigaction(SIGPROF, &sa, 0);
+ sigaction(SIGSYS, &sa, 0);
+ sigaction(SIGTRAP, &sa, 0);
+ sigaction(SIGVTALRM, &sa, 0);
+ sigaction(SIGXCPU, &sa, 0);
+ sigaction(SIGXFSZ, &sa, 0);
+}
+
+
+#define PARSE_FLAGS_NOTSUPP_OK 0x0001
+#define PARSE_FLAGS_FORCE_FN 0x0002
+
+static void parse_salt(char *salt_str, int flags)
+{
+ unsigned char buf[EXT4_MAX_SALT_SIZE];
+ char *cp = salt_str;
+ unsigned char *salt_buf;
+ int fd, ret, salt_len = 0;
+
+ if (flags & PARSE_FLAGS_FORCE_FN)
+ goto salt_from_filename;
+ if (strncmp(cp, "s:", 2) == 0) {
+ cp += 2;
+ salt_len = strlen(cp);
+ if (salt_len >= EXT4_MAX_SALT_SIZE)
+ goto invalid_salt;
+ strncpy((char *) buf, cp, sizeof(buf));
+ } else if (cp[0] == '/') {
+ salt_from_filename:
+ fd = open(cp, O_RDONLY | O_DIRECTORY);
+ if (fd == -1 && errno == ENOTDIR)
+ fd = open(cp, O_RDONLY);
+ if (fd == -1) {
+ perror(cp);
+ exit(1);
+ }
+ ret = ioctl(fd, EXT4_IOC_GET_ENCRYPTION_PWSALT, &buf);
+ close(fd);
+ if (ret < 0) {
+ if (flags & PARSE_FLAGS_NOTSUPP_OK)
+ return;
+ perror("EXT4_IOC_GET_ENCRYPTION_PWSALT");
+ exit(1);
+ }
+ if (options & OPT_VERBOSE) {
+ char tmp[80];
+ uuid_unparse(buf, tmp);
+ printf("%s has pw salt %s\n", cp, tmp);
+ }
+ salt_len = 16;
+ } else if (strncmp(cp, "f:", 2) == 0) {
+ cp += 2;
+ goto salt_from_filename;
+ } else if (strncmp(cp, "0x", 2) == 0) {
+ unsigned char *h, *l;
+
+ cp += 2;
+ if (strlen(cp) & 1)
+ goto invalid_salt;
+ while (*cp) {
+ if (salt_len >= EXT4_MAX_SALT_SIZE)
+ goto invalid_salt;
+ h = memchr(hexchars, *cp++, hexchars_size);
+ l = memchr(hexchars, *cp++, hexchars_size);
+ if (!h || !l)
+ goto invalid_salt;
+ buf[salt_len++] =
+ (((unsigned char)(h - hexchars) << 4) +
+ (unsigned char)(l - hexchars));
+ }
+ } else if (uuid_parse(cp, buf) == 0) {
+ salt_len = 16;
+ } else {
+ invalid_salt:
+ fprintf(stderr, "Invalid salt: %s\n", salt_str);
+ exit(1);
+ }
+ salt_buf = malloc(salt_len);
+ if (!salt_buf) {
+ fprintf(stderr, "Couldn't allocate salt\n");
+ exit(1);
+ }
+ memcpy(salt_buf, buf, salt_len);
+ add_salt(salt_buf, salt_len);
+}
+
+static void set_policy(struct salt *set_salt, int pad,
+ int argc, char *argv[], int path_start_index)
+{
+ struct salt *salt;
+ struct ext4_encryption_policy policy;
+ uuid_t uu;
+ int fd;
+ int x;
+ int rc;
+
+ if ((pad != 4) && (pad != 8) &&
+ (pad != 16) && (pad != 32)) {
+ fprintf(stderr, "Invalid padding %d\n", pad);
+ exit(1);
+ }
+
+ for (x = path_start_index; x < argc; x++) {
+ fd = open(argv[x], O_DIRECTORY);
+ if (fd == -1) {
+ perror(argv[x]);
+ exit(1);
+ }
+ if (set_salt)
+ salt = set_salt;
+ else {
+ if (ioctl(fd, EXT4_IOC_GET_ENCRYPTION_PWSALT,
+ &uu) < 0) {
+ perror("EXT4_IOC_GET_ENCRYPTION_PWSALT");
+ exit(1);
+ }
+ salt = find_by_salt(uu, sizeof(uu));
+ if (!salt) {
+ fprintf(stderr, "Couldn't find salt!?!\n");
+ exit(1);
+ }
+ }
+ policy.version = 0;
+ policy.contents_encryption_mode =
+ EXT4_ENCRYPTION_MODE_AES_256_XTS;
+ policy.filenames_encryption_mode =
+ EXT4_ENCRYPTION_MODE_AES_256_CTS;
+ policy.flags = int_log2(pad >> 2);
+ memcpy(policy.master_key_descriptor, salt->key_desc,
+ EXT4_KEY_DESCRIPTOR_SIZE);
+ rc = ioctl(fd, EXT4_IOC_SET_ENCRYPTION_POLICY, &policy);
+ close(fd);
+ if (rc) {
+ printf("Error [%s] setting policy.\nThe key descriptor "
+ "[%s] may not match the existing encryption "
+ "context for directory [%s].\n",
+ strerror(errno), salt->key_ref_str, argv[x]);
+ continue;
+ }
+ printf("Key with descriptor [%s] applied to %s.\n",
+ salt->key_ref_str, argv[x]);
+ }
+}
+
+static void pbkdf2_sha512(const char *passphrase, struct salt *salt,
+ unsigned int count,
+ unsigned char derived_key[EXT4_MAX_KEY_SIZE])
+{
+ size_t passphrase_size = strlen(passphrase);
+ unsigned char buf[SHA512_LENGTH + EXT4_MAX_PASSPHRASE_SIZE] = {0};
+ unsigned char tempbuf[SHA512_LENGTH] = {0};
+ char final[SHA512_LENGTH] = {0};
+ unsigned char saltbuf[EXT4_MAX_SALT_SIZE + EXT4_MAX_PASSPHRASE_SIZE] = {0};
+ int actual_buf_len = SHA512_LENGTH + passphrase_size;
+ int actual_saltbuf_len = EXT4_MAX_SALT_SIZE + passphrase_size;
+ unsigned int x, y;
+ __u32 *final_u32 = (__u32 *)final;
+ __u32 *temp_u32 = (__u32 *)tempbuf;
+
+ if (passphrase_size > EXT4_MAX_PASSPHRASE_SIZE) {
+ printf("Passphrase size is %zd; max is %d.\n", passphrase_size,
+ EXT4_MAX_PASSPHRASE_SIZE);
+ exit(1);
+ }
+ if (salt->salt_len > EXT4_MAX_SALT_SIZE) {
+ printf("Salt size is %zd; max is %d.\n", salt->salt_len,
+ EXT4_MAX_SALT_SIZE);
+ exit(1);
+ }
+ assert(EXT4_MAX_KEY_SIZE <= SHA512_LENGTH);
+
+ memcpy(saltbuf, salt->salt, salt->salt_len);
+ memcpy(&saltbuf[EXT4_MAX_SALT_SIZE], passphrase, passphrase_size);
+
+ memcpy(&buf[SHA512_LENGTH], passphrase, passphrase_size);
+
+ for (x = 0; x < count; ++x) {
+ if (x == 0) {
+ ext2fs_sha512(saltbuf, actual_saltbuf_len, tempbuf);
+ } else {
+ /*
+ * buf: [previous hash || passphrase]
+ */
+ memcpy(buf, tempbuf, SHA512_LENGTH);
+ ext2fs_sha512(buf, actual_buf_len, tempbuf);
+ }
+ for (y = 0; y < (sizeof(final) / sizeof(*final_u32)); ++y)
+ final_u32[y] = final_u32[y] ^ temp_u32[y];
+ }
+ memcpy(derived_key, final, EXT4_MAX_KEY_SIZE);
+}
+
+static int disable_echo(struct termios *saved_settings)
+{
+ struct termios current_settings;
+ int rc = 0;
+
+ rc = tcgetattr(0, &current_settings);
+ if (rc)
+ return rc;
+ *saved_settings = current_settings;
+ current_settings.c_lflag &= ~ECHO;
+ rc = tcsetattr(0, TCSANOW, &current_settings);
+
+ return rc;
+}
+
+static void get_passphrase(char *passphrase, int len)
+{
+ char *p;
+ struct termios current_settings;
+
+ assert(len > 0);
+ disable_echo(&current_settings);
+ p = fgets(passphrase, len, stdin);
+ tcsetattr(0, TCSANOW, &current_settings);
+ printf("\n");
+ if (!p) {
+ printf("Aborting.\n");
+ exit(1);
+ }
+ p = strrchr(passphrase, '\n');
+ if (!p)
+ p = passphrase + len - 1;
+ *p = '\0';
+}
+
+struct keyring_map {
+ char name[4];
+ size_t name_len;
+ int code;
+};
+
+static const struct keyring_map keyrings[] = {
+ {"@us", 3, KEY_SPEC_USER_SESSION_KEYRING},
+ {"@u", 2, KEY_SPEC_USER_KEYRING},
+ {"@s", 2, KEY_SPEC_SESSION_KEYRING},
+ {"@g", 2, KEY_SPEC_GROUP_KEYRING},
+ {"@p", 2, KEY_SPEC_PROCESS_KEYRING},
+ {"@t", 2, KEY_SPEC_THREAD_KEYRING},
+};
+
+static int get_keyring_id(const char *keyring)
+{
+ unsigned int x;
+ char *end;
+
+ /*
+ * If no keyring is specified, by default use either the user
+ * session keyring or the session keyring. Fetching the
+ * session keyring will return the user session keyring if no
+ * session keyring has been set.
+ */
+ if (keyring == NULL)
+ return KEY_SPEC_SESSION_KEYRING;
+ for (x = 0; x < (sizeof(keyrings) / sizeof(keyrings[0])); ++x) {
+ if (strcmp(keyring, keyrings[x].name) == 0) {
+ return keyrings[x].code;
+ }
+ }
+ x = strtoul(keyring, &end, 10);
+ if (*end == '\0') {
+ if (keyctl(KEYCTL_DESCRIBE, x, NULL, 0) < 0)
+ return 0;
+ return x;
+ }
+ return 0;
+}
+
+static void generate_key_ref_str(struct salt *salt)
+{
+ unsigned char key_ref1[SHA512_LENGTH];
+ unsigned char key_ref2[SHA512_LENGTH];
+ int x;
+
+ ext2fs_sha512(salt->key, EXT4_MAX_KEY_SIZE, key_ref1);
+ ext2fs_sha512(key_ref1, SHA512_LENGTH, key_ref2);
+ memcpy(salt->key_desc, key_ref2, EXT4_KEY_DESCRIPTOR_SIZE);
+ for (x = 0; x < EXT4_KEY_DESCRIPTOR_SIZE; ++x) {
+ sprintf(&salt->key_ref_str[x * 2], "%02x",
+ salt->key_desc[x]);
+ }
+ salt->key_ref_str[EXT4_KEY_REF_STR_BUF_SIZE - 1] = '\0';
+}
+
+static void insert_key_into_keyring(const char *keyring, struct salt *salt)
+{
+ int keyring_id = get_keyring_id(keyring);
+ struct ext4_encryption_key key;
+ char key_ref_full[EXT2FS_KEY_DESC_PREFIX_SIZE +
+ EXT4_KEY_REF_STR_BUF_SIZE];
+ int rc;
+
+ if (keyring_id == 0) {
+ printf("Invalid keyring [%s].\n", keyring);
+ exit(1);
+ }
+ sprintf(key_ref_full, "%s%s", EXT2FS_KEY_DESC_PREFIX,
+ salt->key_ref_str);
+ rc = keyctl(KEYCTL_SEARCH, keyring_id, EXT2FS_KEY_TYPE_LOGON,
+ key_ref_full, 0);
+ if (rc != -1) {
+ if ((options & OPT_QUIET) == 0)
+ printf("Key with descriptor [%s] already exists\n",
+ salt->key_ref_str);
+ return;
+ } else if ((rc == -1) && (errno != ENOKEY)) {
+ printf("keyctl_search failed: %s\n", strerror(errno));
+ if (errno == EINVAL)
+ printf("Keyring [%s] is not available.\n", keyring);
+ exit(1);
+ }
+ key.mode = EXT4_ENCRYPTION_MODE_AES_256_XTS;
+ memcpy(key.raw, salt->key, EXT4_MAX_KEY_SIZE);
+ key.size = EXT4_MAX_KEY_SIZE;
+
+ /*
+ * We need to do this instead of simply adding the key to
+ * KEY_SPEC_SESSION_KEYRING since trying to add a key to a
+ * session keyring that does not yet exist will cause the
+ * kernel to create a session keyring --- which will then get
+ * garbage collected as soon as e4crypt exits.
+ *
+ * The fact that the keyctl system call and the add_key system
+ * call treats KEY_SPEC_SESSION_KEYRING differently when a
+ * session keyring does not exist is very unfortunate and
+ * confusing, but so it goes...
+ */
+ if (keyring_id == KEY_SPEC_SESSION_KEYRING) {
+ keyring_id = keyctl(KEYCTL_GET_KEYRING_ID, keyring_id, 0);
+ if (keyring_id < 0) {
+ printf("Error getting session keyring ID: %s\n",
+ strerror(errno));
+ exit(1);
+ }
+ }
+ rc = add_key(EXT2FS_KEY_TYPE_LOGON, key_ref_full, (void *)&key,
+ sizeof(key), keyring_id);
+ if (rc == -1) {
+ if (errno == EDQUOT) {
+ printf("Error adding key to keyring; quota exceeded\n");
+ } else {
+ printf("Error adding key with key descriptor [%s]: "
+ "%s\n", salt->key_ref_str, strerror(errno));
+ }
+ exit(1);
+ } else {
+ if ((options & OPT_QUIET) == 0)
+ printf("Added key with descriptor [%s]\n",
+ salt->key_ref_str);
+ }
+}
+
+static void get_default_salts(void)
+{
+ FILE *f = setmntent("/etc/mtab", "r");
+ struct mntent *mnt;
+
+ while (f && ((mnt = getmntent(f)) != NULL)) {
+ if (strcmp(mnt->mnt_type, "ext4") ||
+ access(mnt->mnt_dir, R_OK))
+ continue;
+ parse_salt(mnt->mnt_dir, PARSE_FLAGS_NOTSUPP_OK);
+ }
+ endmntent(f);
+}
+
+/* Functions which implement user commands */
+
+struct cmd_desc {
+ const char *cmd_name;
+ void (*cmd_func)(int, char **, const struct cmd_desc *);
+ const char *cmd_desc;
+ const char *cmd_help;
+ int cmd_flags;
+};
+
+#define CMD_HIDDEN 0x0001
+
+static void do_help(int argc, char **argv, const struct cmd_desc *cmd);
+
+#define add_key_desc "adds a key to the user's keyring"
+#define add_key_help \
+"e4crypt add_key -S salt [ -k keyring ] [-v] [-q] [ -p pad ] [ path ... ]\n\n" \
+"Prompts the user for a passphrase and inserts it into the specified\n" \
+"keyring. If no keyring is specified, e4crypt will use the session\n" \
+"keyring if it exists or the user session keyring if it does not.\n\n" \
+"If one or more directory paths are specified, e4crypt will try to\n" \
+"set the policy of those directories to use the key just entered by\n" \
+"the user.\n"
+
+static void do_add_key(int argc, char **argv, const struct cmd_desc *cmd)
+{
+ struct salt *salt;
+ bool explicit_salt = false;
+ char *keyring = NULL;
+ int i, opt, pad = 4;
+ unsigned j;
+
+ while ((opt = getopt(argc, argv, "k:S:p:vq")) != -1) {
+ switch (opt) {
+ case 'k':
+ /* Specify a keyring. */
+ keyring = optarg;
+ break;
+ case 'p':
+ pad = atoi(optarg);
+ break;
+ case 'S':
+ if (explicit_salt) {
+ fputs("May only provide -S once\n", stderr);
+ exit(1);
+ }
+ /* Salt value for passphrase. */
+ parse_salt(optarg, 0);
+ explicit_salt = true;
+ break;
+ case 'v':
+ options |= OPT_VERBOSE;
+ break;
+ case 'q':
+ options |= OPT_QUIET;
+ break;
+ default:
+ case '?':
+ if (opt != '?')
+ fprintf(stderr, "Unrecognized option: %c\n",
+ opt);
+ fputs("USAGE:\n ", stderr);
+ fputs(cmd->cmd_help, stderr);
+ exit(1);
+ }
+ }
+ if (num_salt == 0)
+ get_default_salts();
+ if (num_salt == 0) {
+ fprintf(stderr, "No salt values available\n");
+ exit(1);
+ }
+ validate_paths(argc, argv, optind);
+ if (!explicit_salt)
+ for (i = optind; i < argc; i++)
+ parse_salt(argv[i], PARSE_FLAGS_FORCE_FN);
+ printf("Enter passphrase (echo disabled): ");
+ get_passphrase(in_passphrase, sizeof(in_passphrase));
+ for (j = 0, salt = salt_list; j < num_salt; j++, salt++) {
+ pbkdf2_sha512(in_passphrase, salt,
+ EXT4_PBKDF2_ITERATIONS, salt->key);
+ generate_key_ref_str(salt);
+ insert_key_into_keyring(keyring, salt);
+ }
+ if (optind != argc) {
+ salt = explicit_salt ? salt_list : NULL;
+ set_policy(salt, pad, argc, argv, optind);
+ }
+ clear_secrets();
+ exit(0);
+}
+
+#define set_policy_desc "sets a policy for directories"
+#define set_policy_help \
+"e4crypt set_policy [ -p pad ] policy path ... \n\n" \
+"Sets the policy for the directories specified on the command line.\n" \
+"All directories must be empty to set the policy; if the directory\n" \
+"already has a policy established, e4crypt will validate that it the\n" \
+"policy matches what was specified. A policy is an encryption key\n" \
+"identifier consisting of 16 hexadecimal characters.\n"
+
+static void do_set_policy(int argc, char **argv, const struct cmd_desc *cmd)
+{
+ struct salt saltbuf;
+ int c, pad = 4;
+
+ while ((c = getopt (argc, argv, "p:")) != EOF) {
+ switch (c) {
+ case 'p':
+ pad = atoi(optarg);
+ break;
+ }
+ }
+
+ if (argc < optind + 2) {
+ fprintf(stderr, "Missing required argument(s).\n\n");
+ fputs("USAGE:\n ", stderr);
+ fputs(cmd->cmd_help, stderr);
+ exit(1);
+ }
+
+ if ((strlen(argv[optind]) != (EXT4_KEY_DESCRIPTOR_SIZE * 2)) ||
+ hex2byte(argv[optind], (EXT4_KEY_DESCRIPTOR_SIZE * 2),
+ saltbuf.key_desc, EXT4_KEY_DESCRIPTOR_SIZE)) {
+ printf("Invalid key descriptor [%s]. Valid characters "
+ "are 0-9 and a-f, lower case. "
+ "Length must be %d.\n",
+ argv[optind], (EXT4_KEY_DESCRIPTOR_SIZE * 2));
+ exit(1);
+ }
+ validate_paths(argc, argv, optind+1);
+ strcpy(saltbuf.key_ref_str, argv[optind]);
+ set_policy(&saltbuf, pad, argc, argv, optind+1);
+ exit(0);
+}
+
+#define get_policy_desc "get the encryption for directories"
+#define get_policy_help \
+"e4crypt get_policy path ... \n\n" \
+"Gets the policy for the directories specified on the command line.\n"
+
+static void do_get_policy(int argc, char **argv, const struct cmd_desc *cmd)
+{
+ struct ext4_encryption_policy policy;
+ int i, j, fd, rc;
+
+ if (argc < 2) {
+ fprintf(stderr, "Missing required argument(s).\n\n");
+ fputs("USAGE:\n ", stderr);
+ fputs(cmd->cmd_help, stderr);
+ exit(1);
+ }
+
+ for (i = 1; i < argc; i++) {
+ fd = open(argv[i], O_RDONLY);
+ if (fd == -1) {
+ perror(argv[i]);
+ exit(1);
+ }
+ rc = ioctl(fd, EXT4_IOC_GET_ENCRYPTION_POLICY, &policy);
+ close(fd);
+ if (rc) {
+ printf("Error getting policy for %s: %s\n",
+ argv[i], strerror(errno));
+ continue;
+ }
+ printf("%s: ", argv[i]);
+ for (j = 0; j < EXT4_KEY_DESCRIPTOR_SIZE; j++) {
+ printf("%02x", (unsigned char) policy.master_key_descriptor[j]);
+ }
+ fputc('\n', stdout);
+ }
+ exit(0);
+}
+
+#define new_session_desc "give the invoking process a new session keyring"
+#define new_session_help \
+"e4crypt new_session\n\n" \
+"Give the invoking process (typically a shell) a new session keyring,\n" \
+"discarding its old session keyring.\n"
+
+static void do_new_session(int argc, char **argv EXT2FS_ATTR((unused)),
+ const struct cmd_desc *cmd)
+{
+ long keyid, ret;
+
+ if (argc > 1) {
+ fputs("Excess arguments\n\n", stderr);
+ fputs(cmd->cmd_help, stderr);
+ exit(1);
+ }
+ keyid = keyctl(KEYCTL_JOIN_SESSION_KEYRING, NULL);
+ if (keyid < 0) {
+ perror("KEYCTL_JOIN_SESSION_KEYRING");
+ exit(1);
+ }
+ ret = keyctl(KEYCTL_SESSION_TO_PARENT, NULL);
+ if (ret < 0) {
+ perror("KEYCTL_SESSION_TO_PARENT");
+ exit(1);
+ }
+ printf("Switched invoking process to new session keyring %ld\n", keyid);
+ exit(0);
+}
+
+#define CMD(name) { #name, do_##name, name##_desc, name##_help, 0 }
+#define _CMD(name) { #name, do_##name, NULL, NULL, CMD_HIDDEN }
+
+const struct cmd_desc cmd_list[] = {
+ _CMD(help),
+ CMD(add_key),
+ CMD(get_policy),
+ CMD(new_session),
+ CMD(set_policy),
+ { NULL, NULL, NULL, NULL, 0 }
+};
+
+static void do_help(int argc, char **argv,
+ const struct cmd_desc *cmd EXT2FS_ATTR((unused)))
+{
+ const struct cmd_desc *p;
+
+ if (argc > 1) {
+ for (p = cmd_list; p->cmd_name; p++) {
+ if (p->cmd_flags & CMD_HIDDEN)
+ continue;
+ if (strcmp(p->cmd_name, argv[1]) == 0) {
+ putc('\n', stdout);
+ fputs("USAGE:\n ", stdout);
+ fputs(p->cmd_help, stdout);
+ exit(0);
+ }
+ }
+ printf("Unknown command: %s\n\n", argv[1]);
+ }
+
+ fputs("Available commands:\n", stdout);
+ for (p = cmd_list; p->cmd_name; p++) {
+ if (p->cmd_flags & CMD_HIDDEN)
+ continue;
+ printf(" %-20s %s\n", p->cmd_name, p->cmd_desc);
+ }
+ printf("\nTo get more information on a command, "
+ "type 'e4crypt help cmd'\n");
+ exit(0);
+}
+
+int main(int argc, char *argv[])
+{
+ const struct cmd_desc *cmd;
+
+ if (argc < 2)
+ do_help(argc, argv, cmd_list);
+
+ sigcatcher_setup();
+ for (cmd = cmd_list; cmd->cmd_name; cmd++) {
+ if (strcmp(cmd->cmd_name, argv[1]) == 0) {
+ cmd->cmd_func(argc-1, argv+1, cmd);
+ exit(0);
+ }
+ }
+ printf("Unknown command: %s\n\n", argv[1]);
+ do_help(1, argv, cmd_list);
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 15:25:11 +0000