X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=lib%2Futils_crypt.c;h=a5d9904d2bb2418e9c1a3997a4c3da26e9d0e8d7;hb=5dc654433c3816fd726f29c73a0fcdc0484148b8;hp=6ad4196e299ef6f4017c47088202b6f478f46ce8;hpb=a70b27762d9f17bf569d181c6bd8d6299df26807;p=platform%2Fupstream%2Fcryptsetup.git

diff --git a/lib/utils_crypt.c b/lib/utils_crypt.c
index 6ad4196..a5d9904 100644
--- a/lib/utils_crypt.c
+++ b/lib/utils_crypt.c
@@ -1,8 +1,30 @@
+/*
+ * 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.
+ *
+ * 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.
+ *
+ * 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>
@@ -13,22 +35,44 @@
 #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;
 	}
 
@@ -48,7 +92,9 @@ void *crypt_safe_alloc(size_t size)
 		return NULL;
 
 	alloc->size = size;
+	memset(&alloc->data, 0, size);
 
+	/* coverity[leaked_storage] */
 	return &alloc->data;
 }
 
@@ -59,7 +105,8 @@ void crypt_safe_free(void *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);
 
@@ -69,14 +116,15 @@ void crypt_safe_free(void *data)
 
 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;
@@ -143,7 +191,7 @@ static int interactive_pass(const char *prompt, char *pass, size_t maxlen,
 	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);
@@ -161,135 +209,328 @@ out_err:
 	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;
+
+	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;
+	}
 
-int crypt_get_key(char *prompt, char **key, unsigned int *passLen, int key_size,
+	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 || 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;
+	}
+
+	/* 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(fd != STDIN_FILENO)
-		close(fd);
-	return 0;
 
+	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;
 }