+/*
+ * utils_crypt - cipher utilities for cryptsetup
+ *
+ * Copyright (C) 2004-2007, Clemens Fruhwirth <clemens@endorphin.org>
+ * Copyright (C) 2009-2012, Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2009-2012, Milan Broz
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
#include <stdlib.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
+#include <ctype.h>
+#include <limits.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "nls.h"
#include "utils_crypt.h"
+#define log_dbg(x) crypt_log(NULL, CRYPT_LOG_DEBUG, x)
+#define log_err(cd, x) crypt_log(cd, CRYPT_LOG_ERROR, x)
+
struct safe_allocation {
size_t size;
char data[0];
};
-int crypt_parse_name_and_mode(const char *s, char *cipher, char *cipher_mode)
+int crypt_parse_name_and_mode(const char *s, char *cipher, int *key_nums,
+ char *cipher_mode)
{
if (sscanf(s, "%" MAX_CIPHER_LEN_STR "[^-]-%" MAX_CIPHER_LEN_STR "s",
cipher, cipher_mode) == 2) {
if (!strcmp(cipher_mode, "plain"))
strncpy(cipher_mode, "cbc-plain", 10);
+ if (key_nums) {
+ char *tmp = strchr(cipher, ':');
+ *key_nums = tmp ? atoi(++tmp) : 1;
+ if (!*key_nums)
+ return -EINVAL;
+ }
+
+ return 0;
+ }
+
+ /* Short version for "empty" cipher */
+ if (!strcmp(s, "null")) {
+ strncpy(cipher, "cipher_null", MAX_CIPHER_LEN);
+ strncpy(cipher_mode, "ecb", 9);
+ if (key_nums)
+ *key_nums = 0;
return 0;
}
if (sscanf(s, "%" MAX_CIPHER_LEN_STR "[^-]", cipher) == 1) {
strncpy(cipher_mode, "cbc-plain", 10);
+ if (key_nums)
+ *key_nums = 1;
return 0;
}
return -EINVAL;
}
+/*
+ * Replacement for memset(s, 0, n) on stack that can be optimized out
+ * Also used in safe allocations for explicit memory wipe.
+ */
+void crypt_memzero(void *s, size_t n)
+{
+ volatile uint8_t *p = (volatile uint8_t *)s;
+
+ while(n--)
+ *p++ = 0;
+}
+
/* safe allocations */
void *crypt_safe_alloc(size_t size)
{
return NULL;
alloc->size = size;
+ crypt_memzero(&alloc->data, size);
+ /* coverity[leaked_storage] */
return &alloc->data;
}
if (!data)
return;
- alloc = data - offsetof(struct safe_allocation, data);
+ alloc = (struct safe_allocation *)
+ ((char *)data - offsetof(struct safe_allocation, data));
- memset(data, 0, alloc->size);
+ crypt_memzero(data, alloc->size);
alloc->size = 0x55aa55aa;
free(alloc);
void *crypt_safe_realloc(void *data, size_t size)
{
+ struct safe_allocation *alloc;
void *new_data;
new_data = crypt_safe_alloc(size);
if (new_data && data) {
- struct safe_allocation *alloc;
- alloc = data - offsetof(struct safe_allocation, data);
+ alloc = (struct safe_allocation *)
+ ((char *)data - offsetof(struct safe_allocation, data));
if (size > alloc->size)
size = alloc->size;
static int timed_read(int fd, char *pass, size_t maxlen, long timeout)
{
struct timeval t;
- fd_set fds;
+ fd_set fds = {}; /* Just to avoid scan-build false report for FD_SET */
int failed = -1;
FD_ZERO(&fds);
{
struct termios orig, tmp;
int failed = -1;
- int infd = STDIN_FILENO, outfd;
+ int infd, outfd;
if (maxlen < 1)
- goto out_err;
+ return failed;
/* Read and write to /dev/tty if available */
- if ((infd = outfd = open("/dev/tty", O_RDWR)) == -1) {
+ infd = open("/dev/tty", O_RDWR);
+ if (infd == -1) {
infd = STDIN_FILENO;
outfd = STDERR_FILENO;
- }
+ } else
+ outfd = infd;
if (tcgetattr(infd, &orig))
goto out_err;
memcpy(&tmp, &orig, sizeof(tmp));
tmp.c_lflag &= ~ECHO;
- if (write(outfd, prompt, strlen(prompt)) < 0)
+ if (prompt && write(outfd, prompt, strlen(prompt)) < 0)
goto out_err;
tcsetattr(infd, TCSAFLUSH, &tmp);
tcsetattr(infd, TCSAFLUSH, &orig);
out_err:
- if (!failed && write(outfd, "\n", 1));
+ if (!failed && write(outfd, "\n", 1)) {};
if (infd != STDIN_FILENO)
close(infd);
return failed;
}
+static int crypt_get_key_tty(const char *prompt,
+ char **key, size_t *key_size,
+ int timeout, int verify,
+ struct crypt_device *cd)
+{
+ int key_size_max = DEFAULT_PASSPHRASE_SIZE_MAX;
+ int r = -EINVAL;
+ char *pass = NULL, *pass_verify = NULL;
+
+ log_dbg("Interactive passphrase entry requested.");
+
+ pass = crypt_safe_alloc(key_size_max + 1);
+ if (!pass) {
+ log_err(cd, _("Out of memory while reading passphrase.\n"));
+ return -ENOMEM;
+ }
+
+ if (interactive_pass(prompt, pass, key_size_max, timeout)) {
+ log_err(cd, _("Error reading passphrase from terminal.\n"));
+ goto out_err;
+ }
+ pass[key_size_max] = '\0';
+
+ if (verify) {
+ pass_verify = crypt_safe_alloc(key_size_max);
+ if (!pass_verify) {
+ log_err(cd, _("Out of memory while reading passphrase.\n"));
+ r = -ENOMEM;
+ goto out_err;
+ }
+
+ if (interactive_pass(_("Verify passphrase: "),
+ pass_verify, key_size_max, timeout)) {
+ log_err(cd, _("Error reading passphrase from terminal.\n"));
+ goto out_err;
+ }
+
+ if (strncmp(pass, pass_verify, key_size_max)) {
+ log_err(cd, _("Passphrases do not match.\n"));
+ r = -EPERM;
+ goto out_err;
+ }
+ }
+
+ *key = pass;
+ *key_size = strlen(pass);
+ r = 0;
+out_err:
+ crypt_safe_free(pass_verify);
+ if (r)
+ crypt_safe_free(pass);
+ return r;
+}
+
/*
- * Password reading behaviour matrix of get_key
- * FIXME: rewrite this from scratch.
- * p v n h
- * -----------------+---+---+---+---
- * interactive | Y | Y | Y | Inf
- * from fd | N | N | Y | Inf
- * from binary file | N | N | N | Inf or options->key_size
- *
- * Legend: p..prompt, v..can verify, n..newline-stop, h..read horizon
- *
- * Note: --key-file=- is interpreted as a read from a binary file (stdin)
+ * A simple call to lseek(3) might not be possible for some inputs (e.g.
+ * reading from a pipe), so this function instead reads of up to BUFSIZ bytes
+ * at a time until the specified number of bytes. It returns -1 on read error
+ * or when it reaches EOF before the requested number of bytes have been
+ * discarded.
*/
+static int keyfile_seek(int fd, size_t bytes)
+{
+ char tmp[BUFSIZ];
+ size_t next_read;
+ ssize_t bytes_r;
+ off_t r;
-int crypt_get_key(char *prompt, char **key, unsigned int *passLen, int key_size,
+ r = lseek(fd, bytes, SEEK_CUR);
+ if (r > 0)
+ return 0;
+ if (r < 0 && errno != ESPIPE)
+ return -1;
+
+ while (bytes > 0) {
+ /* figure out how much to read */
+ next_read = bytes > sizeof(tmp) ? sizeof(tmp) : bytes;
+
+ bytes_r = read(fd, tmp, next_read);
+ if (bytes_r < 0) {
+ if (errno == EINTR)
+ continue;
+
+ /* read error */
+ return -1;
+ }
+
+ if (bytes_r == 0)
+ /* EOF */
+ break;
+
+ bytes -= bytes_r;
+ }
+
+ return bytes == 0 ? 0 : -1;
+}
+
+/*
+ * Note: --key-file=- is interpreted as a read from a binary file (stdin)
+ * key_size_max == 0 means detect maximum according to input type (tty/file)
+ * timeout and verify options only applies to tty input
+ */
+int crypt_get_key(const char *prompt,
+ char **key, size_t *key_size,
+ size_t keyfile_offset, size_t keyfile_size_max,
const char *key_file, int timeout, int verify,
struct crypt_device *cd)
{
- int fd = -1;
+ int fd, regular_file, read_stdin, char_read, unlimited_read = 0;
+ int r = -EINVAL;
char *pass = NULL;
- int read_horizon;
- int regular_file = 0;
- int read_stdin;
- int r;
+ size_t buflen, i, file_read_size;
struct stat st;
+ *key = NULL;
+ *key_size = 0;
+
/* Passphrase read from stdin? */
read_stdin = (!key_file || !strcmp(key_file, "-")) ? 1 : 0;
- /* read_horizon applies only for real keyfile, not stdin or terminal */
- read_horizon = (key_file && !read_stdin) ? key_size : 0 /* until EOF */;
+ if (read_stdin && isatty(STDIN_FILENO)) {
+ if (keyfile_offset) {
+ log_err(cd, _("Cannot use offset with terminal input.\n"));
+ return -EINVAL;
+ }
+ return crypt_get_key_tty(prompt, key, key_size, timeout, verify, cd);
+ }
+
+ if (read_stdin)
+ log_dbg("STDIN descriptor passphrase entry requested.");
+ else
+ log_dbg("File descriptor passphrase entry requested.");
+
+ /* If not requsted otherwise, we limit input to prevent memory exhaustion */
+ if (keyfile_size_max == 0) {
+ keyfile_size_max = DEFAULT_KEYFILE_SIZE_MAXKB * 1024;
+ unlimited_read = 1;
+ }
- /* Setup file descriptior */
fd = read_stdin ? STDIN_FILENO : open(key_file, O_RDONLY);
if (fd < 0) {
- crypt_log(cd, CRYPT_LOG_ERROR,
- _("Failed to open key file.\n"));
- goto out_err;
+ log_err(cd, _("Failed to open key file.\n"));
+ return -EINVAL;
}
- /* Interactive case */
- if(isatty(fd)) {
- int i;
-
- pass = crypt_safe_alloc(MAX_TTY_PASSWORD_LEN);
- if (!pass || (i = interactive_pass(prompt, pass, MAX_TTY_PASSWORD_LEN, timeout))) {
- crypt_log(cd, CRYPT_LOG_ERROR,
- _("Error reading passphrase from terminal.\n"));
+ /* use 4k for buffer (page divisor but avoid huge pages) */
+ buflen = 4096 - sizeof(struct safe_allocation);
+ regular_file = 0;
+ if(!read_stdin) {
+ if(stat(key_file, &st) < 0) {
+ log_err(cd, _("Failed to stat key file.\n"));
goto out_err;
}
- if (verify) {
- char pass_verify[MAX_TTY_PASSWORD_LEN];
- i = interactive_pass(_("Verify passphrase: "), pass_verify, sizeof(pass_verify), timeout);
- if (i || strcmp(pass, pass_verify) != 0) {
- crypt_log(cd, CRYPT_LOG_ERROR,
- _("Passphrases do not match.\n"));
- goto out_err;
- }
- memset(pass_verify, 0, sizeof(pass_verify));
- }
- *passLen = strlen(pass);
- *key = pass;
- } else {
- /*
- * This is either a fd-input or a file, in neither case we can verify the input,
- * however we don't stop on new lines if it's a binary file.
- */
- int buflen, i;
-
- /* The following for control loop does an exhausting
- * read on the key material file, if requested with
- * key_size == 0, as it's done by LUKS. However, we
- * should warn the user, if it's a non-regular file,
- * such as /dev/random, because in this case, the loop
- * will read forever.
- */
- if(!read_stdin && read_horizon == 0) {
- if(stat(key_file, &st) < 0) {
- crypt_log(cd, CRYPT_LOG_ERROR,
- _("Failed to stat key file.\n"));
+ if(S_ISREG(st.st_mode)) {
+ regular_file = 1;
+ file_read_size = (size_t)st.st_size;
+
+ if (keyfile_offset > file_read_size) {
+ log_err(cd, _("Cannot seek to requested keyfile offset.\n"));
goto out_err;
}
- if(!S_ISREG(st.st_mode))
- crypt_log(cd, CRYPT_LOG_NORMAL,
- _("Warning: exhausting read requested, but key file"
- " is not a regular file, function might never return.\n"));
- else
- regular_file = 1;
+ file_read_size -= keyfile_offset;
+
+ /* known keyfile size, alloc it in one step */
+ if (file_read_size >= keyfile_size_max)
+ buflen = keyfile_size_max;
+ else if (file_read_size)
+ buflen = file_read_size;
}
- buflen = 0;
- for(i = 0; read_horizon == 0 || i < read_horizon; i++) {
- if(i >= buflen - 1) {
- buflen += 128;
- pass = crypt_safe_realloc(pass, buflen);
- if (!pass) {
- crypt_log(cd, CRYPT_LOG_ERROR,
- _("Out of memory while reading passphrase.\n"));
- goto out_err;
- }
- }
+ }
+
+ pass = crypt_safe_alloc(buflen);
+ if (!pass) {
+ log_err(cd, _("Out of memory while reading passphrase.\n"));
+ goto out_err;
+ }
+
+ /* Discard keyfile_offset bytes on input */
+ if (keyfile_offset && keyfile_seek(fd, keyfile_offset) < 0) {
+ log_err(cd, _("Cannot seek to requested keyfile offset.\n"));
+ goto out_err;
+ }
- r = read(fd, pass + i, 1);
- if (r < 0) {
- crypt_log(cd, CRYPT_LOG_ERROR,
- _("Error reading passphrase.\n"));
+ for(i = 0; i < keyfile_size_max; i++) {
+ if(i == buflen) {
+ buflen += 4096;
+ pass = crypt_safe_realloc(pass, buflen);
+ if (!pass) {
+ log_err(cd, _("Out of memory while reading passphrase.\n"));
+ r = -ENOMEM;
goto out_err;
}
-
- /* Stop on newline only if not requested read from keyfile */
- if(r == 0 || (!key_file && pass[i] == '\n'))
- break;
}
- /* Fail if piped input dies reading nothing */
- if(!i && !regular_file)
+
+ char_read = read(fd, &pass[i], 1);
+ if (char_read < 0) {
+ log_err(cd, _("Error reading passphrase.\n"));
goto out_err;
- pass[i] = 0;
- *key = pass;
- *passLen = i;
+ }
+
+ /* Stop on newline only if not requested read from keyfile */
+ if(char_read == 0 || (!key_file && pass[i] == '\n'))
+ break;
}
- if(fd != STDIN_FILENO)
- close(fd);
- return 0;
+ /* Fail if piped input dies reading nothing */
+ if(!i && !regular_file) {
+ log_dbg("Nothing read on input.");
+ r = -EPIPE;
+ goto out_err;
+ }
+
+ /* Fail if we exceeded internal default (no specified size) */
+ if (unlimited_read && i == keyfile_size_max) {
+ log_err(cd, _("Maximum keyfile size exceeded.\n"));
+ goto out_err;
+ }
+
+ if (!unlimited_read && i != keyfile_size_max) {
+ log_err(cd, _("Cannot read requested amount of data.\n"));
+ goto out_err;
+ }
+
+ *key = pass;
+ *key_size = i;
+ r = 0;
out_err:
- if(fd >= 0 && fd != STDIN_FILENO)
+ if(fd != STDIN_FILENO)
close(fd);
- if(pass)
+
+ if (r)
crypt_safe_free(pass);
- *key = NULL;
- *passLen = 0;
- return -EINVAL;
+ return r;
+}
+
+ssize_t crypt_hex_to_bytes(const char *hex, char **result, int safe_alloc)
+{
+ char buf[3] = "xx\0", *endp, *bytes;
+ size_t i, len;
+
+ len = strlen(hex);
+ if (len % 2)
+ return -EINVAL;
+ len /= 2;
+
+ bytes = safe_alloc ? crypt_safe_alloc(len) : malloc(len);
+ if (!bytes)
+ return -ENOMEM;
+
+ for (i = 0; i < len; i++) {
+ memcpy(buf, &hex[i * 2], 2);
+ bytes[i] = strtoul(buf, &endp, 16);
+ if (endp != &buf[2]) {
+ safe_alloc ? crypt_safe_free(bytes) : free(bytes);
+ return -EINVAL;
+ }
+ }
+ *result = bytes;
+ return i;
+}
+
+/*
+ * Device size string parsing, suffixes:
+ * s|S - 512 bytes sectors
+ * k |K |m |M |g |G |t |T - 1024 base
+ * kiB|KiB|miB|MiB|giB|GiB|tiB|TiB - 1024 base
+ * kb |KB |mM |MB |gB |GB |tB |TB - 1000 base
+ */
+int crypt_string_to_size(struct crypt_device *cd, const char *s, uint64_t *size)
+{
+ char *endp = NULL;
+ size_t len;
+ uint64_t mult_base, mult, tmp;
+
+ *size = strtoull(s, &endp, 10);
+ if (!isdigit(s[0]) ||
+ (errno == ERANGE && *size == ULLONG_MAX) ||
+ (errno != 0 && *size == 0))
+ return -EINVAL;
+
+ if (!endp || !*endp)
+ return 0;
+
+ len = strlen(endp);
+ /* Allow "B" and "iB" suffixes */
+ if (len > 3 ||
+ (len == 3 && (endp[1] != 'i' || endp[2] != 'B')) ||
+ (len == 2 && endp[1] != 'B'))
+ return -EINVAL;
+
+ if (len == 1 || len == 3)
+ mult_base = 1024;
+ else
+ mult_base = 1000;
+
+ mult = 1;
+ switch (endp[0]) {
+ case 's':
+ case 'S': mult = 512;
+ break;
+ case 't':
+ case 'T': mult *= mult_base;
+ /* Fall through */
+ case 'g':
+ case 'G': mult *= mult_base;
+ /* Fall through */
+ case 'm':
+ case 'M': mult *= mult_base;
+ /* Fall through */
+ case 'k':
+ case 'K': mult *= mult_base;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ tmp = *size * mult;
+ if ((tmp / *size) != mult) {
+ log_dbg("Device size overflow.");
+ return -EINVAL;
+ }
+
+ *size = tmp;
+ return 0;
}
projects / platform / upstream / cryptsetup.git / blobdiff