Disallow header restore if context is nonLUKS device.

[platform/upstream/cryptsetup.git] / lib / utils_crypt.c

diff --git a/lib/utils_crypt.c b/lib/utils_crypt.c
index c2111c7..a5d9904 100644 (file)
--- a/lib/utils_crypt.c
+++ b/lib/utils_crypt.c
@@ -92,7 +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;
 }
 
@@ -262,6 +264,49 @@ 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
@@ -274,7 +319,7 @@ int crypt_get_key(const char *prompt,
 {
        int fd, regular_file, read_stdin, char_read, unlimited_read = 0;
        int r = -EINVAL;
-       char *pass = NULL, tmp;
+       char *pass = NULL;
        size_t buflen, i, file_read_size;
        struct stat st;
 
@@ -342,11 +387,10 @@ int crypt_get_key(const char *prompt,
        }
 
        /* Discard keyfile_offset bytes on input */
-       for(i = 0; i < keyfile_offset; i++)
-               if (read(fd, &tmp, 1) != 1) {
-                       log_err(cd, _("Cannot seek to requested keyfile offset.\n"));
-                       goto out_err;
-               }
+       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) {
@@ -467,10 +511,13 @@ int crypt_string_to_size(struct crypt_device *cd, const char *s, uint64_t *size)
                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;