From 8cf3ca80680b43015971cbbf4625517ae859d50c Mon Sep 17 00:00:00 2001 From: Jan Janssen Date: Sat, 13 Jul 2013 13:19:38 +0200 Subject: cryptsetup: Add tcrypt support Tcrypt uses a different approach to passphrases/key files. The passphrase and all key files are incorporated into the "password" to open the volume. So, the idea of slots that provide a way to open the volume with different passphrases/key files that are independent from each other like with LUKS does not apply. Therefore, we use the key file from /etc/crypttab as the source for the passphrase. The actual key files that are combined with the passphrase into a password are provided as a new option in /etc/crypttab and can be given multiple times if more than one key file is used by a volume. --- src/cryptsetup/cryptsetup.c | 79 ++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 75 insertions(+), 4 deletions(-) (limited to 'src/cryptsetup') diff --git a/src/cryptsetup/cryptsetup.c b/src/cryptsetup/cryptsetup.c index e84ebba683..3a2cfe459b 100644 --- a/src/cryptsetup/cryptsetup.c +++ b/src/cryptsetup/cryptsetup.c @@ -27,6 +27,7 @@ #include #include +#include "fileio.h" #include "log.h" #include "util.h" #include "path-util.h" @@ -34,7 +35,7 @@ #include "ask-password-api.h" #include "def.h" -static const char *opt_type = NULL; /* LUKS1 or PLAIN */ +static const char *opt_type = NULL; /* CRYPT_LUKS1, CRYPT_TCRYPT or CRYPT_PLAIN */ static char *opt_cipher = NULL; static unsigned opt_key_size = 0; static unsigned opt_keyfile_size = 0; @@ -44,6 +45,9 @@ static unsigned opt_tries = 0; static bool opt_readonly = false; static bool opt_verify = false; static bool opt_discards = false; +static bool opt_tcrypt_hidden = false; +static bool opt_tcrypt_system = false; +static char **opt_tcrypt_keyfiles = NULL; static usec_t opt_timeout = 0; /* Options Debian's crypttab knows we don't: @@ -82,6 +86,14 @@ static int parse_one_option(const char *option) { return 0; } + } else if (startswith(option, "tcrypt-keyfile=")) { + + opt_type = CRYPT_TCRYPT; + if (path_is_absolute(option+15)) + opt_tcrypt_keyfiles = strv_append(opt_tcrypt_keyfiles, strdup(option+15)); + else + log_error("Key file path '%s' is not absolute. Ignoring.", option+15); + } else if (startswith(option, "keyfile-size=")) { if (safe_atou(option+13, &opt_keyfile_size) < 0) { @@ -121,7 +133,15 @@ static int parse_one_option(const char *option) { opt_discards = true; else if (streq(option, "luks")) opt_type = CRYPT_LUKS1; - else if (streq(option, "plain") || + else if (streq(option, "tcrypt")) + opt_type = CRYPT_TCRYPT; + else if (streq(option, "tcrypt-hidden")) { + opt_type = CRYPT_TCRYPT; + opt_tcrypt_hidden = true; + } else if (streq(option, "tcrypt-system")) { + opt_type = CRYPT_TCRYPT; + opt_tcrypt_system = true; + } else if (streq(option, "plain") || streq(option, "swap") || streq(option, "tmp")) opt_type = CRYPT_PLAIN; @@ -301,6 +321,53 @@ static int get_password(const char *name, usec_t until, bool accept_cached, char return 0; } +static int attach_tcrypt(struct crypt_device *cd, + const char *name, + const char *key_file, + char **passwords, + uint32_t flags) { + int r = 0; + _cleanup_free_ char *passphrase = NULL; + struct crypt_params_tcrypt params = { + .flags = CRYPT_TCRYPT_LEGACY_MODES, + .keyfiles = (const char **)opt_tcrypt_keyfiles, + .keyfiles_count = strv_length(opt_tcrypt_keyfiles) + }; + + assert(cd); + assert(name); + assert(key_file || passwords); + + if (opt_tcrypt_hidden) + params.flags |= CRYPT_TCRYPT_HIDDEN_HEADER; + + if (opt_tcrypt_system) + params.flags |= CRYPT_TCRYPT_SYSTEM_HEADER; + + if (key_file) { + r = read_one_line_file(key_file, &passphrase); + if (r < 0) { + log_error("Failed to read password file '%s': %s", key_file, strerror(-r)); + return -EAGAIN; + } + + params.passphrase = passphrase; + } else + params.passphrase = passwords[0]; + params.passphrase_size = strlen(params.passphrase); + + r = crypt_load(cd, CRYPT_TCRYPT, ¶ms); + if (r < 0) { + if (key_file && r == -EPERM) { + log_error("Failed to activate using password file '%s'.", key_file); + return -EAGAIN; + } + return r; + } + + return crypt_activate_by_volume_key(cd, name, NULL, 0, flags);; +} + static int attach_luks_or_plain(struct crypt_device *cd, const char *name, const char *key_file, @@ -450,7 +517,7 @@ int main(int argc, char *argv[]) { !streq(argv[4], "none")) { if (!path_is_absolute(argv[4])) - log_error("Password file path %s is not absolute. Ignoring.", argv[4]); + log_error("Password file path '%s' is not absolute. Ignoring.", argv[4]); else key_file = argv[4]; } @@ -532,7 +599,10 @@ int main(int argc, char *argv[]) { goto finish; } - k = attach_luks_or_plain(cd, argv[2], key_file, passwords, flags); + if (streq_ptr(opt_type, CRYPT_TCRYPT)) + k = attach_tcrypt(cd, argv[2], key_file, passwords, flags); + else + k = attach_luks_or_plain(cd, argv[2], key_file, passwords, flags); if (k >= 0) break; else if (k == -EAGAIN) { @@ -583,6 +653,7 @@ finish: free(opt_cipher); free(opt_hash); + strv_free(opt_tcrypt_keyfiles); return r; } -- cgit v1.2.3-54-g00ecf