1 files changed, 302 insertions, 7 deletions

diff --git a/vold/devmapper.c b/vold/devmapper.c
index c7fd167..ef44c90 100644
--- a/vold/devmapper.c
+++ b/vold/devmapper.c
@@ -26,6 +26,7 @@
 #include <sys/mount.h>
 
 #include <linux/loop.h>
+#include <linux/dm-ioctl.h>
 
 #include <cutils/config_utils.h>
 #include <cutils/properties.h>
@@ -35,6 +36,167 @@
 
 #define DEBUG_DEVMAPPER 1
 
+static void *_align(void *ptr, unsigned int a)
+{
+        register unsigned long agn = --a;
+
+        return (void *) (((unsigned long) ptr + agn) & ~agn);
+}
+
+static struct dm_ioctl *_dm_ioctl_setup(struct devmapping *dm, int flags)
+{
+    void *buffer;
+    void *p;
+    const size_t min_size = 16 * 1024;
+    size_t len = sizeof(struct dm_ioctl);
+    struct dm_ioctl *io;
+    struct dm_target_spec *tgt;
+    int i;
+    char params[1024];
+    char key[80];
+
+    key[0] = '\0';
+    for (i = 0; i < (int) sizeof(dm->key); i++) {
+        char tmp[8];
+
+        sprintf(tmp, "%02x", dm->key[i]);
+        strcat(key, tmp);
+    }
+
+    char srcdev[128];
+
+    // XXX: Handle non crypt targets and non twofish (use param)
+    if (dm->src_type == dmsrc_loopback)
+        strcpy(srcdev, dm->type_data.loop.loop_dev);
+    else if (dm->src_type == dmsrc_partition)
+        strcpy(srcdev, dm->type_data.part.part_dev);
+
+    sprintf(params, "twofish %s 0 %s 0", key, srcdev);
+
+LOG_VOL("Params = '%s'", params);
+
+    if (len < min_size)
+        len = min_size;
+
+    if (!(buffer = malloc(len))) {
+        LOGE("out of memory");
+        return NULL;
+    }
+
+    memset(buffer, 0, len);
+    io = buffer;
+    tgt = (struct dm_target_spec *) &buffer[sizeof(struct dm_ioctl)];
+
+    io->version[0] = 4;
+    io->version[1] = 0;
+    io->version[2] = 0;
+
+    io->data_size = len;
+    io->data_start = sizeof(struct dm_ioctl);
+
+    io->flags = flags;
+    io->dev = 0;
+
+    io->target_count = 1;
+    io->event_nr = 1;
+    strncpy(io->name, dm->target, sizeof(io->name));
+
+    tgt->status = 0;
+    tgt->sector_start = 0;
+    tgt->length = (dm->size_mb * (1024 * 1024)) / 512;
+    strncpy(tgt->target_type, "crypt", sizeof(tgt->target_type));
+
+    p = buffer + sizeof(struct dm_ioctl) + sizeof(struct dm_target_spec);
+    strcpy((char *) p, params);
+    p+= strlen(params) + 1;
+
+    p = _align(p, 8);
+    tgt->next = p - buffer;
+
+    return io;
+}
+
+static int get_next_available_dm()
+{
+    int i;
+
+    for (i = 0; i < 8; i++) {
+        char path[255];
+        sprintf(path, "/dev/block/dm-%d", i);
+        if ((access(path, F_OK) < 0) && (errno == ENOENT))
+            return i;
+    }
+
+    LOGE("Out of device mapper numbers");
+    return -1;
+}
+
+static int create_devmapping(struct devmapping *dm)
+{
+    struct dm_ioctl *io;
+    int rc, fd;
+
+#if DEBUG_DEVMAPPER
+    LOG_VOL("create_devmapping():");
+#endif
+
+    if (dm->dm_no < 0) {
+        LOGE("Invalid dm_no set");
+        return -EINVAL;
+    }
+
+    if ((fd = open("/dev/device-mapper", O_RDWR)) < 0) {
+        LOGE("Error opening device mapper (%d)", errno);
+        return -errno;
+    }
+
+    if (!(io = _dm_ioctl_setup(dm, 0))) {
+        LOGE("Unable to setup ioctl (out of memory)");
+        close(fd);
+        return -ENOMEM;
+    }
+
+    if ((rc = ioctl(fd, DM_DEV_CREATE, io)) < 0) {
+        LOGE("device-mapper create ioctl failed (%d)", errno);
+        rc = -errno;
+        goto out_free;
+    }
+
+    free(io);
+
+    if (!(io = _dm_ioctl_setup(dm, DM_STATUS_TABLE_FLAG))) {
+        LOGE("Unable to setup ioctl (out of memory)");
+        rc = -ENOMEM;
+        goto out_nofree;
+    }
+
+    if ((rc = ioctl(fd, DM_TABLE_LOAD, io)) < 0) {
+        LOGE("device-mapper load ioctl failed (%d)", errno);
+        rc = -errno;
+        goto out_free;
+    }
+
+    free(io);
+
+    if (!(io = _dm_ioctl_setup(dm, 0))) {
+        LOGE("Unable to setup ioctl (out of memory)");
+        rc = -ENOMEM;
+        goto out_nofree;
+    }
+
+    if ((rc = ioctl(fd, DM_DEV_SUSPEND, io)) < 0) {
+        LOGE("device-mapper resume ioctl failed (%d)", errno);
+        rc = -errno;
+        goto out_free;
+    }
+
+out_free:
+    free (io);
+out_nofree:
+    close (fd);
+    return rc;
+}
+
 static int loopback_start(struct devmapping *dm)
 {
     int i;
@@ -52,7 +214,7 @@ static int loopback_start(struct devmapping *dm)
         sprintf(filename, "/dev/block/loop%d", i);
 
         if ((fd = open(filename, O_RDWR)) < 0) {
-            LOGE("Unable to open %s (%s)\n", filename, strerror(errno));
+            LOGE("Unable to open %s (%s)", filename, strerror(errno));
             return -errno;
         }
 
@@ -63,27 +225,27 @@ static int loopback_start(struct devmapping *dm)
         close(fd);
 
         if (rc < 0) {
-            LOGE("Unable to get loop status for %s (%s)\n", filename,
+            LOGE("Unable to get loop status for %s (%s)", filename,
                  strerror(errno));
             return -errno;
         }
     }
 
     if (i == MAX_LOOP) {
-        LOGE("Out of loop devices\n");
+        LOGE("Out of loop devices");
         return -ENOSPC;
     }
 
     int file_fd;
 
     if ((file_fd = open(dm->type_data.loop.loop_src, O_RDWR)) < 0) {
-        LOGE("Unable to open %s (%s)\n", dm->type_data.loop.loop_src,
+        LOGE("Unable to open %s (%s)", dm->type_data.loop.loop_src,
              strerror(errno));
         return -errno;
     }
 
     if (ioctl(fd, LOOP_SET_FD, file_fd) < 0) {
-        LOGE("Error setting up loopback interface (%s)\n", strerror(errno));
+        LOGE("Error setting up loopback interface (%s)", strerror(errno));
         return -errno;
     }
 
@@ -94,7 +256,7 @@ static int loopback_start(struct devmapping *dm)
     close(file_fd);
 
 #if DEBUG_DEVMAPPER
-    LOG_VOL("Loop setup on %s for %s\n", dm->type_data.loop.loop_dev,
+    LOG_VOL("Loop setup on %s for %s", dm->type_data.loop.loop_dev,
             dm->type_data.loop.loop_src);
 #endif
 
@@ -124,12 +286,17 @@ int devmapper_start(struct devmapping *dm)
     /*
      * Configure the device mapper
      */
+    if ((rc = create_devmapping(dm)) < 0) {
+        LOGE("Failed to create devmapping (%d)", rc);
+        // XXX: if loopback then tear down
+        return rc;
+    }
 
     return 0;
 }
 
 struct devmapping *devmapper_init(char *src, char *src_type, uint32_t size_mb,
-                  char *target, char *params, char *tgt_fs)
+                  char *target, char *params, char *tgt_fs, char *mediapath)
 {
     struct devmapping *dm;
 
@@ -161,8 +328,136 @@ struct devmapping *devmapper_init(char *src, char *src_type, uint32_t size_mb,
     dm->target = strdup(target);
     dm->params = strdup(params);
     dm->tgt_fs = strdup(tgt_fs);
+    
+    if ((dm->dm_no = get_next_available_dm()) < 0)
+        goto out_free;
+
+    sprintf(mediapath, "/devices/virtual/block/dm-%d", dm->dm_no);
+
+    if (!(dm->media = media_create(mediapath,
+                                   "unknown",
+                                   "unknown",
+                                   media_devmapper))) {
+        LOGE("Unable to create media");
+        goto out_free;
+    }
 
     return dm;
  out_free:
+    if (dm->target)
+        free(dm->target);
+    if (dm->params)
+        free(dm->params);
+    if (dm->tgt_fs)
+        free(dm->tgt_fs);
+
+    free(dm);
     return NULL;
 }
+
+int devmapper_genesis(struct devmapping *dm)
+{
+
+    if (dm->src_type == dmsrc_loopback) {
+        int fd;
+
+        LOG_VOL("devmapper_genesis(): Working on %s", 
+                dm->type_data.loop.loop_src);
+
+        unlink(dm->type_data.loop.loop_src);
+
+        LOG_VOL("devmapper_genesis(): Creating imagefile (%u MB)",
+                dm->size_mb);
+
+        if ((fd = creat(dm->type_data.loop.loop_src, 0600)) < 0) {
+            LOGE("Error creating imagefile (%s)", strerror(errno));
+            return -errno;
+        }
+
+        if (ftruncate(fd, (dm->size_mb * (1024 * 1024))) < 0) {
+            LOGE("Error truncating imagefile (%s)", strerror(errno));
+            close(fd);
+            return -errno;
+        }
+        close(fd);
+    } else if (dm->src_type == dmsrc_partition) {
+        LOGE("partition maps not yet supported");
+        return -ENOSYS;
+    }
+
+    return devmapper_start(dm);
+}
+
+static int destroy_devmapping(struct devmapping *dm)
+{
+    struct dm_ioctl       *io;
+    int                   dmFd;
+    int                   rc = 0;
+
+    LOG_VOL("destroy_devmapping():");
+
+    if ((dmFd = open("/dev/device-mapper", O_RDWR)) < 0) {
+        LOGE("Error opening device mapper (%d)", errno);
+        return -errno;
+    }
+
+    if (!(io = _dm_ioctl_setup(dm, DM_PERSISTENT_DEV_FLAG))) {
+        LOGE("Unable to setup ioctl (out of memory)");
+        rc = -ENOMEM;
+        goto out_nofree;
+    }
+
+    if ((rc = ioctl(dmFd, DM_DEV_REMOVE, io)) < 0) {
+        LOGE("device-mapper remove ioctl failed (%d)", errno);
+        rc = -errno;
+        goto out_free;
+    }
+
+out_free:
+    free (io);
+out_nofree:
+    close (dmFd);
+    return rc;
+}
+
+static int loopback_stop(struct devmapping *dm)
+{
+    char devname[255];
+    int device_fd;
+    int rc = 0;
+
+    LOG_VOL("loopback_stop():");
+
+    device_fd = open(dm->type_data.loop.loop_dev, O_RDONLY);
+    if (device_fd < 0) {
+        LOG_ERROR("Failed to open loop (%d)", errno);
+        return -errno;
+    }
+
+    if (ioctl(device_fd, LOOP_CLR_FD, 0) < 0) {
+        LOG_ERROR("Failed to destroy loop (%d)", errno);
+        rc = -errno;
+    }
+
+    close(device_fd);
+    return rc;
+}
+
+int devmapper_stop(struct devmapping *dm)
+{
+    int rc;
+
+    LOG_VOL("devmapper_stop():");
+
+    if ((rc = destroy_devmapping(dm)))
+        return rc;
+
+    if (dm->src_type == dmsrc_loopback) {
+        if ((rc = loopback_stop(dm)))
+            return rc;
+    } else if (dm->src_type == dmsrc_partition) {
+        LOGE("partition maps not yet supported");
+        return -ENOSYS;
+    }
+    return 0;
+}