/*
- * util_crypt - cipher utilities for cryptsetup
+ * utils_crypt - cipher utilities for cryptsetup
*
* Copyright (C) 2004-2007, Clemens Fruhwirth <clemens@endorphin.org>
- * Copyright (C) 2009-2011, Red Hat, Inc. All rights reserved.
+ * 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
- * version 2 as published by the Free Software Foundation.
+ * 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
#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>
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)
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;
}
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);
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;
}
/*
+ * 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;
+
+ 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_size_max, const char *key_file,
- int timeout, int verify,
+ size_t keyfile_offset, size_t keyfile_size_max,
+ const char *key_file, int timeout, int verify,
struct crypt_device *cd)
{
int fd, regular_file, read_stdin, char_read, unlimited_read = 0;
int r = -EINVAL;
char *pass = NULL;
- size_t buflen, i;
+ size_t buflen, i, file_read_size;
struct stat st;
*key = NULL;
/* Passphrase read from stdin? */
read_stdin = (!key_file || !strcmp(key_file, "-")) ? 1 : 0;
- if(read_stdin && isatty(STDIN_FILENO))
+ 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.");
}
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;
+ }
+ file_read_size -= keyfile_offset;
+
/* known keyfile size, alloc it in one step */
- if ((size_t)st.st_size >= keyfile_size_max)
+ if (file_read_size >= keyfile_size_max)
buflen = keyfile_size_max;
- else if (st.st_size)
- buflen = st.st_size;
+ else if (file_read_size)
+ buflen = file_read_size;
}
}
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;
+ }
+
for(i = 0; i < keyfile_size_max; i++) {
if(i == buflen) {
buflen += 4096;
/* Fail if we exceeded internal default (no specified size) */
if (unlimited_read && i == keyfile_size_max) {
- log_err(cd, _("Maximum keyfile size exceeeded.\n"));
+ log_err(cd, _("Maximum keyfile size exceeded.\n"));
goto out_err;
}
crypt_safe_free(pass);
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