diff --git a/sim/src/lib.rs b/sim/src/lib.rs
index e04f06f..8131a70 100644
--- a/sim/src/lib.rs
+++ b/sim/src/lib.rs
@@ -1,33 +1,26 @@
 use docopt::Docopt;
-use log::{info, warn, error};
-use rand::{
-    distributions::{IndependentSample, Range},
-    Rng, SeedableRng, XorShiftRng,
-};
+use log::{warn, error};
 use std::{
     fmt,
-    mem,
     process,
-    slice,
-};
-use aes_ctr::{
-    Aes128Ctr,
-    stream_cipher::{
-        generic_array::GenericArray,
-        NewFixStreamCipher,
-        StreamCipherCore,
-    },
 };
 use serde_derive::Deserialize;
 
 mod caps;
+mod image;
 mod tlv;
 pub mod testlog;
 
-use simflash::{Flash, SimFlash, SimFlashMap};
+use simflash::{SimFlash, SimFlashMap};
 use mcuboot_sys::{c, AreaDesc, FlashId};
-use crate::caps::Caps;
-use crate::tlv::{TlvGen, TlvFlags, AES_SEC_KEY};
+
+use crate::image::{
+    Images,
+    install_image,
+    mark_upgrade,
+    SlotInfo,
+    show_sizes,
+};
 
 const USAGE: &'static str = "
 Mcuboot simulator
@@ -401,1044 +394,3 @@
         }
     }
 }
-
-impl Images {
-    /// A simple upgrade without forced failures.
-    ///
-    /// Returns the number of flash operations which can later be used to
-    /// inject failures at chosen steps.
-    pub fn run_basic_upgrade(&self) -> Result<i32, ()> {
-        let (flashmap, total_count) = try_upgrade(&self.flashmap, &self, None);
-        info!("Total flash operation count={}", total_count);
-
-        if !verify_image(&flashmap, &self.slots, 0, &self.upgrades) {
-            warn!("Image mismatch after first boot");
-            Err(())
-        } else {
-            Ok(total_count)
-        }
-    }
-
-    #[cfg(feature = "overwrite-only")]
-    pub fn run_basic_revert(&self) -> bool {
-        false
-    }
-
-    #[cfg(not(feature = "overwrite-only"))]
-    pub fn run_basic_revert(&self) -> bool {
-        let mut fails = 0;
-
-        // FIXME: this test would also pass if no swap is ever performed???
-        if Caps::SwapUpgrade.present() {
-            for count in 2 .. 5 {
-                info!("Try revert: {}", count);
-                let flashmap = try_revert(&self.flashmap, &self.areadesc, count);
-                if !verify_image(&flashmap, &self.slots, 0, &self.primaries) {
-                    error!("Revert failure on count {}", count);
-                    fails += 1;
-                }
-            }
-        }
-
-        fails > 0
-    }
-
-    pub fn run_perm_with_fails(&self) -> bool {
-        let mut fails = 0;
-        let total_flash_ops = self.total_count.unwrap();
-
-        // Let's try an image halfway through.
-        for i in 1 .. total_flash_ops {
-            info!("Try interruption at {}", i);
-            let (flashmap, count) = try_upgrade(&self.flashmap, &self, Some(i));
-            info!("Second boot, count={}", count);
-            if !verify_image(&flashmap, &self.slots, 0, &self.upgrades) {
-                warn!("FAIL at step {} of {}", i, total_flash_ops);
-                fails += 1;
-            }
-
-            if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                               BOOT_FLAG_SET, BOOT_FLAG_SET) {
-                warn!("Mismatched trailer for Slot 0");
-                fails += 1;
-            }
-
-            if !verify_trailer(&flashmap, &self.slots, 1, BOOT_MAGIC_UNSET,
-                               BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-                warn!("Mismatched trailer for Slot 1");
-                fails += 1;
-            }
-
-            if Caps::SwapUpgrade.present() {
-                if !verify_image(&flashmap, &self.slots, 1, &self.primaries) {
-                    warn!("Slot 1 FAIL at step {} of {}", i, total_flash_ops);
-                    fails += 1;
-                }
-            }
-        }
-
-        if fails > 0 {
-            error!("{} out of {} failed {:.2}%", fails, total_flash_ops,
-                   fails as f32 * 100.0 / total_flash_ops as f32);
-        }
-
-        fails > 0
-    }
-
-    pub fn run_perm_with_random_fails_5(&self) -> bool {
-        self.run_perm_with_random_fails(5)
-    }
-
-    fn run_perm_with_random_fails(&self, total_fails: usize) -> bool {
-        let mut fails = 0;
-        let total_flash_ops = self.total_count.unwrap();
-        let (flashmap, total_counts) = try_random_fails(&self.flashmap, &self,
-                                                        total_flash_ops, total_fails);
-        info!("Random interruptions at reset points={:?}", total_counts);
-
-        let slot0_ok = verify_image(&flashmap, &self.slots, 0, &self.upgrades);
-        let slot1_ok = if Caps::SwapUpgrade.present() {
-            verify_image(&flashmap, &self.slots, 1, &self.primaries)
-        } else {
-            true
-        };
-        if !slot0_ok || !slot1_ok {
-            error!("Image mismatch after random interrupts: slot0={} slot1={}",
-                   if slot0_ok { "ok" } else { "fail" },
-                   if slot1_ok { "ok" } else { "fail" });
-            fails += 1;
-        }
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_SET, BOOT_FLAG_SET) {
-            error!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-        if !verify_trailer(&flashmap, &self.slots, 1, BOOT_MAGIC_UNSET,
-                           BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-            error!("Mismatched trailer for Slot 1");
-            fails += 1;
-        }
-
-        if fails > 0 {
-            error!("Error testing perm upgrade with {} fails", total_fails);
-        }
-
-        fails > 0
-    }
-
-    #[cfg(feature = "overwrite-only")]
-    pub fn run_revert_with_fails(&self) -> bool {
-        false
-    }
-
-    #[cfg(not(feature = "overwrite-only"))]
-    pub fn run_revert_with_fails(&self) -> bool {
-        let mut fails = 0;
-
-        if Caps::SwapUpgrade.present() {
-            for i in 1 .. (self.total_count.unwrap() - 1) {
-                info!("Try interruption at {}", i);
-                if try_revert_with_fail_at(&self.flashmap, &self, i) {
-                    error!("Revert failed at interruption {}", i);
-                    fails += 1;
-                }
-            }
-        }
-
-        fails > 0
-    }
-
-    #[cfg(feature = "overwrite-only")]
-    pub fn run_norevert(&self) -> bool {
-        false
-    }
-
-    #[cfg(not(feature = "overwrite-only"))]
-    pub fn run_norevert(&self) -> bool {
-        let mut flashmap = self.flashmap.clone();
-        let mut fails = 0;
-
-        info!("Try norevert");
-
-        // First do a normal upgrade...
-        let (result, _) = c::boot_go(&mut flashmap, &self.areadesc, None, false);
-        if result != 0 {
-            warn!("Failed first boot");
-            fails += 1;
-        }
-
-        //FIXME: copy_done is written by boot_go, is it ok if no copy
-        //       was ever done?
-
-        if !verify_image(&flashmap, &self.slots, 0, &self.upgrades) {
-            warn!("Slot 0 image verification FAIL");
-            fails += 1;
-        }
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_UNSET, BOOT_FLAG_SET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-        if !verify_trailer(&flashmap, &self.slots, 1, BOOT_MAGIC_UNSET,
-                           BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-            warn!("Mismatched trailer for Slot 1");
-            fails += 1;
-        }
-
-        // Marks image in slot0 as permanent, no revert should happen...
-        mark_permanent_upgrade(&mut flashmap, &self.slots[0]);
-
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_SET, BOOT_FLAG_SET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-
-        let (result, _) = c::boot_go(&mut flashmap, &self.areadesc, None, false);
-        if result != 0 {
-            warn!("Failed second boot");
-            fails += 1;
-        }
-
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_SET, BOOT_FLAG_SET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-        if !verify_image(&flashmap, &self.slots, 0, &self.upgrades) {
-            warn!("Failed image verification");
-            fails += 1;
-        }
-
-        if fails > 0 {
-            error!("Error running upgrade without revert");
-        }
-
-        fails > 0
-    }
-
-    // Tests a new image written to slot0 that already has magic and image_ok set
-    // while there is no image on slot1, so no revert should ever happen...
-    pub fn run_norevert_newimage(&self) -> bool {
-        let mut flashmap = self.flashmap.clone();
-        let mut fails = 0;
-
-        info!("Try non-revert on imgtool generated image");
-
-        mark_upgrade(&mut flashmap, &self.slots[0]);
-
-        // This simulates writing an image created by imgtool to Slot 0
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-
-        // Run the bootloader...
-        let (result, _) = c::boot_go(&mut flashmap, &self.areadesc, None, false);
-        if result != 0 {
-            warn!("Failed first boot");
-            fails += 1;
-        }
-
-        // State should not have changed
-        if !verify_image(&flashmap, &self.slots, 0, &self.primaries) {
-            warn!("Failed image verification");
-            fails += 1;
-        }
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-        if !verify_trailer(&flashmap, &self.slots, 1, BOOT_MAGIC_UNSET,
-                           BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-            warn!("Mismatched trailer for Slot 1");
-            fails += 1;
-        }
-
-        if fails > 0 {
-            error!("Expected a non revert with new image");
-        }
-
-        fails > 0
-    }
-
-    // Tests a new image written to slot0 that already has magic and image_ok set
-    // while there is no image on slot1, so no revert should ever happen...
-    pub fn run_signfail_upgrade(&self) -> bool {
-        let mut flashmap = self.flashmap.clone();
-        let mut fails = 0;
-
-        info!("Try upgrade image with bad signature");
-
-        mark_upgrade(&mut flashmap, &self.slots[0]);
-        mark_permanent_upgrade(&mut flashmap, &self.slots[0]);
-        mark_upgrade(&mut flashmap, &self.slots[1]);
-
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_SET, BOOT_FLAG_UNSET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-
-        // Run the bootloader...
-        let (result, _) = c::boot_go(&mut flashmap, &self.areadesc, None, false);
-        if result != 0 {
-            warn!("Failed first boot");
-            fails += 1;
-        }
-
-        // State should not have changed
-        if !verify_image(&flashmap, &self.slots, 0, &self.primaries) {
-            warn!("Failed image verification");
-            fails += 1;
-        }
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_SET, BOOT_FLAG_UNSET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-
-        if fails > 0 {
-            error!("Expected an upgrade failure when image has bad signature");
-        }
-
-        fails > 0
-    }
-
-    #[cfg(not(feature = "overwrite-only"))]
-    fn trailer_sz(&self, align: usize) -> usize {
-        c::boot_trailer_sz(align as u8) as usize
-    }
-
-    // FIXME: could get status sz from bootloader
-    #[cfg(not(feature = "overwrite-only"))]
-    #[cfg(not(feature = "enc-rsa"))]
-    #[cfg(not(feature = "enc-kw"))]
-    fn status_sz(&self, align: usize) -> usize {
-        self.trailer_sz(align) - (16 + 24)
-    }
-
-    #[cfg(feature = "enc-rsa")]
-    #[cfg(not(feature = "overwrite-only"))]
-    fn status_sz(&self, align: usize) -> usize {
-        self.trailer_sz(align) - (16 + 24 + 32)
-    }
-
-    #[cfg(feature = "enc-kw")]
-    #[cfg(not(feature = "overwrite-only"))]
-    fn status_sz(&self, align: usize) -> usize {
-        self.trailer_sz(align) - (16 + 24 + 32)
-    }
-
-    /// This test runs a simple upgrade with no fails in the images, but
-    /// allowing for fails in the status area. This should run to the end
-    /// and warn that write fails were detected...
-    #[cfg(not(feature = "validate-slot0"))]
-    pub fn run_with_status_fails_complete(&self) -> bool { false }
-
-    #[cfg(feature = "validate-slot0")]
-    pub fn run_with_status_fails_complete(&self) -> bool {
-        let mut flashmap = self.flashmap.clone();
-        let mut fails = 0;
-
-        info!("Try swap with status fails");
-
-        mark_permanent_upgrade(&mut flashmap, &self.slots[1]);
-        self.mark_bad_status_with_rate(&mut flashmap, 0, 1.0);
-
-        let (result, asserts) = c::boot_go(&mut flashmap, &self.areadesc, None, true);
-        if result != 0 {
-            warn!("Failed!");
-            fails += 1;
-        }
-
-        // Failed writes to the marked "bad" region don't assert anymore.
-        // Any detected assert() is happening in another part of the code.
-        if asserts != 0 {
-            warn!("At least one assert() was called");
-            fails += 1;
-        }
-
-        if !verify_trailer(&flashmap, &self.slots, 0, BOOT_MAGIC_GOOD,
-                           BOOT_FLAG_SET, BOOT_FLAG_SET) {
-            warn!("Mismatched trailer for Slot 0");
-            fails += 1;
-        }
-
-        if !verify_image(&flashmap, &self.slots, 0, &self.upgrades) {
-            warn!("Failed image verification");
-            fails += 1;
-        }
-
-        info!("validate slot0 enabled; re-run of boot_go should just work");
-        let (result, _) = c::boot_go(&mut flashmap, &self.areadesc, None, false);
-        if result != 0 {
-            warn!("Failed!");
-            fails += 1;
-        }
-
-        if fails > 0 {
-            error!("Error running upgrade with status write fails");
-        }
-
-        fails > 0
-    }
-
-    /// This test runs a simple upgrade with no fails in the images, but
-    /// allowing for fails in the status area. This should run to the end
-    /// and warn that write fails were detected...
-    #[cfg(feature = "validate-slot0")]
-    pub fn run_with_status_fails_with_reset(&self) -> bool {
-        let mut flashmap = self.flashmap.clone();
-        let mut fails = 0;
-        let mut count = self.total_count.unwrap() / 2;
-
-        //info!("count={}\n", count);
-
-        info!("Try interrupted swap with status fails");
-
-        mark_permanent_upgrade(&mut flashmap, &self.slots[1]);
-        self.mark_bad_status_with_rate(&mut flashmap, 0, 0.5);
-
-        // Should not fail, writing to bad regions does not assert
-        let (_, asserts) = c::boot_go(&mut flashmap, &self.areadesc, Some(&mut count), true);
-        if asserts != 0 {
-            warn!("At least one assert() was called");
-            fails += 1;
-        }
-
-        self.reset_bad_status(&mut flashmap, 0);
-
-        info!("Resuming an interrupted swap operation");
-        let (_, asserts) = c::boot_go(&mut flashmap, &self.areadesc, None, true);
-
-        // This might throw no asserts, for large sector devices, where
-        // a single failure writing is indistinguishable from no failure,
-        // or throw a single assert for small sector devices that fail
-        // multiple times...
-        if asserts > 1 {
-            warn!("Expected single assert validating slot0, more detected {}", asserts);
-            fails += 1;
-        }
-
-        if fails > 0 {
-            error!("Error running upgrade with status write fails");
-        }
-
-        fails > 0
-    }
-
-    /// Adds a new flash area that fails statistically
-    #[cfg(not(feature = "overwrite-only"))]
-    fn mark_bad_status_with_rate(&self, flashmap: &mut SimFlashMap, slot: usize,
-                                 rate: f32) {
-        let dev_id = &self.slots[slot].dev_id;
-        let flash = flashmap.get_mut(&dev_id).unwrap();
-        let align = flash.align();
-        let off = &self.slots[0].base_off;
-        let len = &self.slots[0].len;
-        let status_off = off + len - self.trailer_sz(align);
-
-        // Mark the status area as a bad area
-        let _ = flash.add_bad_region(status_off, self.status_sz(align), rate);
-    }
-
-    #[cfg(feature = "validate-slot0")]
-    fn reset_bad_status(&self, flashmap: &mut SimFlashMap, slot: usize) {
-        let dev_id = &self.slots[slot].dev_id;
-        let flash = flashmap.get_mut(&dev_id).unwrap();
-        flash.reset_bad_regions();
-
-        // Disabling write verification the only assert triggered by
-        // boot_go should be checking for integrity of status bytes.
-        flash.set_verify_writes(false);
-    }
-
-    #[cfg(not(feature = "validate-slot0"))]
-    #[cfg(not(feature = "overwrite-only"))]
-    pub fn run_with_status_fails_with_reset(&self) -> bool {
-        let mut flashmap = self.flashmap.clone();
-        let mut fails = 0;
-
-        info!("Try interrupted swap with status fails");
-
-        mark_permanent_upgrade(&mut flashmap, &self.slots[1]);
-        self.mark_bad_status_with_rate(&mut flashmap, 0, 1.0);
-
-        // This is expected to fail while writing to bad regions...
-        let (_, asserts) = c::boot_go(&mut flashmap, &self.areadesc, None, true);
-        if asserts == 0 {
-            warn!("No assert() detected");
-            fails += 1;
-        }
-
-        fails > 0
-    }
-
-    #[cfg(feature = "overwrite-only")]
-    pub fn run_with_status_fails_with_reset(&self) -> bool {
-        false
-    }
-}
-
-/// Test a boot, optionally stopping after 'n' flash options.  Returns a count
-/// of the number of flash operations done total.
-fn try_upgrade(flashmap: &SimFlashMap, images: &Images,
-               stop: Option<i32>) -> (SimFlashMap, i32) {
-    // Clone the flash to have a new copy.
-    let mut flashmap = flashmap.clone();
-
-    mark_permanent_upgrade(&mut flashmap, &images.slots[1]);
-
-    let mut counter = stop.unwrap_or(0);
-
-    let (first_interrupted, count) = match c::boot_go(&mut flashmap, &images.areadesc, Some(&mut counter), false) {
-        (-0x13579, _) => (true, stop.unwrap()),
-        (0, _) => (false, -counter),
-        (x, _) => panic!("Unknown return: {}", x),
-    };
-
-    counter = 0;
-    if first_interrupted {
-        // fl.dump();
-        match c::boot_go(&mut flashmap, &images.areadesc, Some(&mut counter), false) {
-            (-0x13579, _) => panic!("Shouldn't stop again"),
-            (0, _) => (),
-            (x, _) => panic!("Unknown return: {}", x),
-        }
-    }
-
-    (flashmap, count - counter)
-}
-
-#[cfg(not(feature = "overwrite-only"))]
-fn try_revert(flashmap: &SimFlashMap, areadesc: &AreaDesc, count: usize) -> SimFlashMap {
-    let mut flashmap = flashmap.clone();
-
-    // fl.write_file("image0.bin").unwrap();
-    for i in 0 .. count {
-        info!("Running boot pass {}", i + 1);
-        assert_eq!(c::boot_go(&mut flashmap, &areadesc, None, false), (0, 0));
-    }
-    flashmap
-}
-
-#[cfg(not(feature = "overwrite-only"))]
-fn try_revert_with_fail_at(flashmap: &SimFlashMap, images: &Images,
-                           stop: i32) -> bool {
-    let mut flashmap = flashmap.clone();
-    let mut fails = 0;
-
-    let mut counter = stop;
-    let (x, _) = c::boot_go(&mut flashmap, &images.areadesc, Some(&mut counter), false);
-    if x != -0x13579 {
-        warn!("Should have stopped at interruption point");
-        fails += 1;
-    }
-
-    if !verify_trailer(&flashmap, &images.slots, 0, None, None, BOOT_FLAG_UNSET) {
-        warn!("copy_done should be unset");
-        fails += 1;
-    }
-
-    let (x, _) = c::boot_go(&mut flashmap, &images.areadesc, None, false);
-    if x != 0 {
-        warn!("Should have finished upgrade");
-        fails += 1;
-    }
-
-    if !verify_image(&flashmap, &images.slots, 0, &images.upgrades) {
-        warn!("Image in slot 0 before revert is invalid at stop={}", stop);
-        fails += 1;
-    }
-    if !verify_image(&flashmap, &images.slots, 1, &images.primaries) {
-        warn!("Image in slot 1 before revert is invalid at stop={}", stop);
-        fails += 1;
-    }
-    if !verify_trailer(&flashmap, &images.slots, 0, BOOT_MAGIC_GOOD,
-                       BOOT_FLAG_UNSET, BOOT_FLAG_SET) {
-        warn!("Mismatched trailer for Slot 0 before revert");
-        fails += 1;
-    }
-    if !verify_trailer(&flashmap, &images.slots, 1, BOOT_MAGIC_UNSET,
-                       BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-        warn!("Mismatched trailer for Slot 1 before revert");
-        fails += 1;
-    }
-
-    // Do Revert
-    let (x, _) = c::boot_go(&mut flashmap, &images.areadesc, None, false);
-    if x != 0 {
-        warn!("Should have finished a revert");
-        fails += 1;
-    }
-
-    if !verify_image(&flashmap, &images.slots, 0, &images.primaries) {
-        warn!("Image in slot 0 after revert is invalid at stop={}", stop);
-        fails += 1;
-    }
-    if !verify_image(&flashmap, &images.slots, 1, &images.upgrades) {
-        warn!("Image in slot 1 after revert is invalid at stop={}", stop);
-        fails += 1;
-    }
-    if !verify_trailer(&flashmap, &images.slots, 0, BOOT_MAGIC_GOOD,
-                       BOOT_FLAG_SET, BOOT_FLAG_SET) {
-        warn!("Mismatched trailer for Slot 1 after revert");
-        fails += 1;
-    }
-    if !verify_trailer(&flashmap, &images.slots, 1, BOOT_MAGIC_UNSET,
-                       BOOT_FLAG_UNSET, BOOT_FLAG_UNSET) {
-        warn!("Mismatched trailer for Slot 1 after revert");
-        fails += 1;
-    }
-
-    fails > 0
-}
-
-fn try_random_fails(flashmap: &SimFlashMap, images: &Images,
-                    total_ops: i32,  count: usize) -> (SimFlashMap, Vec<i32>) {
-    let mut flashmap = flashmap.clone();
-
-    mark_permanent_upgrade(&mut flashmap, &images.slots[1]);
-
-    let mut rng = rand::thread_rng();
-    let mut resets = vec![0i32; count];
-    let mut remaining_ops = total_ops;
-    for i in 0 .. count {
-        let ops = Range::new(1, remaining_ops / 2);
-        let reset_counter = ops.ind_sample(&mut rng);
-        let mut counter = reset_counter;
-        match c::boot_go(&mut flashmap, &images.areadesc, Some(&mut counter), false) {
-            (0, _) | (-0x13579, _) => (),
-            (x, _) => panic!("Unknown return: {}", x),
-        }
-        remaining_ops -= reset_counter;
-        resets[i] = reset_counter;
-    }
-
-    match c::boot_go(&mut flashmap, &images.areadesc, None, false) {
-        (-0x13579, _) => panic!("Should not be have been interrupted!"),
-        (0, _) => (),
-        (x, _) => panic!("Unknown return: {}", x),
-    }
-
-    (flashmap, resets)
-}
-
-/// Show the flash layout.
-#[allow(dead_code)]
-fn show_flash(flash: &dyn Flash) {
-    println!("---- Flash configuration ----");
-    for sector in flash.sector_iter() {
-        println!("    {:3}: 0x{:08x}, 0x{:08x}",
-                 sector.num, sector.base, sector.size);
-    }
-    println!("");
-}
-
-/// Install a "program" into the given image.  This fakes the image header, or at least all of the
-/// fields used by the given code.  Returns a copy of the image that was written.
-fn install_image(flashmap: &mut SimFlashMap, slots: &[SlotInfo], slot: usize, len: usize,
-                 bad_sig: bool) -> [Option<Vec<u8>>; 2] {
-    let offset = slots[slot].base_off;
-    let slot_len = slots[slot].len;
-    let dev_id = slots[slot].dev_id;
-
-    let mut tlv = make_tlv();
-
-    const HDR_SIZE: usize = 32;
-
-    // Generate a boot header.  Note that the size doesn't include the header.
-    let header = ImageHeader {
-        magic: 0x96f3b83d,
-        load_addr: 0,
-        hdr_size: HDR_SIZE as u16,
-        _pad1: 0,
-        img_size: len as u32,
-        flags: tlv.get_flags(),
-        ver: ImageVersion {
-            major: (offset / (128 * 1024)) as u8,
-            minor: 0,
-            revision: 1,
-            build_num: offset as u32,
-        },
-        _pad2: 0,
-    };
-
-    let mut b_header = [0; HDR_SIZE];
-    b_header[..32].clone_from_slice(header.as_raw());
-    assert_eq!(b_header.len(), HDR_SIZE);
-
-    tlv.add_bytes(&b_header);
-
-    // The core of the image itself is just pseudorandom data.
-    let mut b_img = vec![0; len];
-    splat(&mut b_img, offset);
-
-    // TLV signatures work over plain image
-    tlv.add_bytes(&b_img);
-
-    // Generate encrypted images
-    let flag = TlvFlags::ENCRYPTED as u32;
-    let is_encrypted = (tlv.get_flags() & flag) == flag;
-    let mut b_encimg = vec![];
-    if is_encrypted {
-        let key = GenericArray::from_slice(AES_SEC_KEY);
-        let nonce = GenericArray::from_slice(&[0; 16]);
-        let mut cipher = Aes128Ctr::new(&key, &nonce);
-        b_encimg = b_img.clone();
-        cipher.apply_keystream(&mut b_encimg);
-    }
-
-    // Build the TLV itself.
-    let mut b_tlv = if bad_sig {
-        let good_sig = &mut tlv.make_tlv();
-        vec![0; good_sig.len()]
-    } else {
-        tlv.make_tlv()
-    };
-
-    // Pad the block to a flash alignment (8 bytes).
-    while b_tlv.len() % 8 != 0 {
-        //FIXME: should be erase_val?
-        b_tlv.push(0xFF);
-    }
-
-    let mut buf = vec![];
-    buf.append(&mut b_header.to_vec());
-    buf.append(&mut b_img);
-    buf.append(&mut b_tlv.clone());
-
-    let mut encbuf = vec![];
-    if is_encrypted {
-        encbuf.append(&mut b_header.to_vec());
-        encbuf.append(&mut b_encimg);
-        encbuf.append(&mut b_tlv);
-    }
-
-    let result: [Option<Vec<u8>>; 2];
-
-    // Since images are always non-encrypted in slot0, we first write an
-    // encrypted image, re-read to use for verification, erase + flash
-    // un-encrypted. In slot1 the image is written un-encrypted, and if
-    // encryption is requested, it follows an erase + flash encrypted.
-
-    let flash = flashmap.get_mut(&dev_id).unwrap();
-
-    if slot == 0 {
-        let enc_copy: Option<Vec<u8>>;
-
-        if is_encrypted {
-            flash.write(offset, &encbuf).unwrap();
-
-            let mut enc = vec![0u8; encbuf.len()];
-            flash.read(offset, &mut enc).unwrap();
-
-            enc_copy = Some(enc);
-
-            flash.erase(offset, slot_len).unwrap();
-        } else {
-            enc_copy = None;
-        }
-
-        flash.write(offset, &buf).unwrap();
-
-        let mut copy = vec![0u8; buf.len()];
-        flash.read(offset, &mut copy).unwrap();
-
-        result = [Some(copy), enc_copy];
-    } else {
-
-        flash.write(offset, &buf).unwrap();
-
-        let mut copy = vec![0u8; buf.len()];
-        flash.read(offset, &mut copy).unwrap();
-
-        let enc_copy: Option<Vec<u8>>;
-
-        if is_encrypted {
-            flash.erase(offset, slot_len).unwrap();
-
-            flash.write(offset, &encbuf).unwrap();
-
-            let mut enc = vec![0u8; encbuf.len()];
-            flash.read(offset, &mut enc).unwrap();
-
-            enc_copy = Some(enc);
-        } else {
-            enc_copy = None;
-        }
-
-        result = [Some(copy), enc_copy];
-    }
-
-    result
-}
-
-// The TLV in use depends on what kind of signature we are verifying.
-#[cfg(feature = "sig-rsa")]
-#[cfg(feature = "enc-kw")]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_rsa_kw()
-}
-
-#[cfg(feature = "sig-rsa")]
-#[cfg(not(feature = "enc-rsa"))]
-#[cfg(not(feature = "enc-kw"))]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_rsa_pss()
-}
-
-#[cfg(feature = "sig-ecdsa")]
-#[cfg(feature = "enc-kw")]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_ecdsa_kw()
-}
-
-#[cfg(feature = "sig-ecdsa")]
-#[cfg(not(feature = "enc-kw"))]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_ecdsa()
-}
-
-#[cfg(not(feature = "sig-rsa"))]
-#[cfg(feature = "enc-rsa")]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_enc_rsa()
-}
-
-#[cfg(feature = "sig-rsa")]
-#[cfg(feature = "enc-rsa")]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_sig_enc_rsa()
-}
-
-#[cfg(not(feature = "sig-rsa"))]
-#[cfg(not(feature = "sig-ecdsa"))]
-#[cfg(feature = "enc-kw")]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_enc_kw()
-}
-
-#[cfg(not(feature = "sig-rsa"))]
-#[cfg(not(feature = "sig-ecdsa"))]
-#[cfg(not(feature = "enc-rsa"))]
-#[cfg(not(feature = "enc-kw"))]
-fn make_tlv() -> TlvGen {
-    TlvGen::new_hash_only()
-}
-
-#[cfg(feature = "enc-rsa")]
-fn find_image(images: &[Option<Vec<u8>>; 2], slot: usize) -> &Vec<u8> {
-    match &images[slot] {
-        Some(image) => return image,
-        None => panic!("Invalid image"),
-    }
-}
-
-#[cfg(feature = "enc-kw")]
-fn find_image(images: &[Option<Vec<u8>>; 2], slot: usize) -> &Vec<u8> {
-    match &images[slot] {
-        Some(image) => return image,
-        None => panic!("Invalid image"),
-    }
-}
-
-#[cfg(not(feature = "enc-rsa"))]
-#[cfg(not(feature = "enc-kw"))]
-fn find_image(images: &[Option<Vec<u8>>; 2], _slot: usize) -> &Vec<u8> {
-    match &images[0] {
-        Some(image) => return image,
-        None => panic!("Invalid image"),
-    }
-}
-
-/// Verify that given image is present in the flash at the given offset.
-fn verify_image(flashmap: &SimFlashMap, slots: &[SlotInfo], slot: usize,
-                images: &[Option<Vec<u8>>; 2]) -> bool {
-    let image = find_image(images, slot);
-    let buf = image.as_slice();
-    let dev_id = slots[slot].dev_id;
-
-    let mut copy = vec![0u8; buf.len()];
-    let offset = slots[slot].base_off;
-    let flash = flashmap.get(&dev_id).unwrap();
-    flash.read(offset, &mut copy).unwrap();
-
-    if buf != &copy[..] {
-        for i in 0 .. buf.len() {
-            if buf[i] != copy[i] {
-                info!("First failure for slot{} at {:#x} {:#x}!={:#x}",
-                      slot, offset + i, buf[i], copy[i]);
-                break;
-            }
-        }
-        false
-    } else {
-        true
-    }
-}
-
-#[cfg(feature = "overwrite-only")]
-#[allow(unused_variables)]
-// overwrite-only doesn't employ trailer management
-fn verify_trailer(flashmap: &SimFlashMap, slots: &[SlotInfo], slot: usize,
-                  magic: Option<u8>, image_ok: Option<u8>,
-                  copy_done: Option<u8>) -> bool {
-    true
-}
-
-#[cfg(not(feature = "overwrite-only"))]
-fn verify_trailer(flashmap: &SimFlashMap, slots: &[SlotInfo], slot: usize,
-                  magic: Option<u8>, image_ok: Option<u8>,
-                  copy_done: Option<u8>) -> bool {
-    let offset = slots[slot].trailer_off;
-    let dev_id = slots[slot].dev_id;
-    let mut copy = vec![0u8; c::boot_magic_sz() + c::boot_max_align() * 2];
-    let mut failed = false;
-
-    let flash = flashmap.get(&dev_id).unwrap();
-    let erased_val = flash.erased_val();
-    flash.read(offset, &mut copy).unwrap();
-
-    failed |= match magic {
-        Some(v) => {
-            if v == 1 && &copy[16..] != MAGIC.unwrap() {
-                warn!("\"magic\" mismatch at {:#x}", offset);
-                true
-            } else if v == 3 {
-                let expected = [erased_val; 16];
-                if &copy[16..] != expected {
-                    warn!("\"magic\" mismatch at {:#x}", offset);
-                    true
-                } else {
-                    false
-                }
-            } else {
-                false
-            }
-        },
-        None => false,
-    };
-
-    failed |= match image_ok {
-        Some(v) => {
-            if (v == 1 && copy[8] != v) || (v == 3 && copy[8] != erased_val) {
-                warn!("\"image_ok\" mismatch at {:#x} v={} val={:#x}", offset, v, copy[8]);
-                true
-            } else {
-                false
-            }
-        },
-        None => false,
-    };
-
-    failed |= match copy_done {
-        Some(v) => {
-            if (v == 1 && copy[0] != v) || (v == 3 && copy[0] != erased_val) {
-                warn!("\"copy_done\" mismatch at {:#x} v={} val={:#x}", offset, v, copy[0]);
-                true
-            } else {
-                false
-            }
-        },
-        None => false,
-    };
-
-    !failed
-}
-
-/// The image header
-#[repr(C)]
-pub struct ImageHeader {
-    magic: u32,
-    load_addr: u32,
-    hdr_size: u16,
-    _pad1: u16,
-    img_size: u32,
-    flags: u32,
-    ver: ImageVersion,
-    _pad2: u32,
-}
-
-impl AsRaw for ImageHeader {}
-
-#[repr(C)]
-pub struct ImageVersion {
-    major: u8,
-    minor: u8,
-    revision: u16,
-    build_num: u32,
-}
-
-#[derive(Clone)]
-struct SlotInfo {
-    base_off: usize,
-    trailer_off: usize,
-    len: usize,
-    dev_id: u8,
-}
-
-pub struct Images {
-    flashmap: SimFlashMap,
-    areadesc: AreaDesc,
-    slots: [SlotInfo; 2],
-    primaries: [Option<Vec<u8>>; 2],
-    upgrades: [Option<Vec<u8>>; 2],
-    total_count: Option<i32>,
-}
-
-const MAGIC: Option<&[u8]> = Some(&[0x77, 0xc2, 0x95, 0xf3,
-                                    0x60, 0xd2, 0xef, 0x7f,
-                                    0x35, 0x52, 0x50, 0x0f,
-                                    0x2c, 0xb6, 0x79, 0x80]);
-
-// Replicates defines found in bootutil.h
-const BOOT_MAGIC_GOOD: Option<u8> = Some(1);
-const BOOT_MAGIC_UNSET: Option<u8> = Some(3);
-
-const BOOT_FLAG_SET: Option<u8> = Some(1);
-const BOOT_FLAG_UNSET: Option<u8> = Some(3);
-
-/// Write out the magic so that the loader tries doing an upgrade.
-fn mark_upgrade(flashmap: &mut SimFlashMap, slot: &SlotInfo) {
-    let flash = flashmap.get_mut(&slot.dev_id).unwrap();
-    let offset = slot.trailer_off + c::boot_max_align() * 2;
-    flash.write(offset, MAGIC.unwrap()).unwrap();
-}
-
-/// Writes the image_ok flag which, guess what, tells the bootloader
-/// the this image is ok (not a test, and no revert is to be performed).
-fn mark_permanent_upgrade(flashmap: &mut SimFlashMap, slot: &SlotInfo) {
-    let flash = flashmap.get_mut(&slot.dev_id).unwrap();
-    let mut ok = [flash.erased_val(); 8];
-    ok[0] = 1u8;
-    let off = slot.trailer_off + c::boot_max_align();
-    let align = flash.align();
-    flash.write(off, &ok[..align]).unwrap();
-}
-
-// Drop some pseudo-random gibberish onto the data.
-fn splat(data: &mut [u8], seed: usize) {
-    let seed_block = [0x135782ea, 0x92184728, data.len() as u32, seed as u32];
-    let mut rng: XorShiftRng = SeedableRng::from_seed(seed_block);
-    rng.fill_bytes(data);
-}
-
-/// Return a read-only view into the raw bytes of this object
-trait AsRaw : Sized {
-    fn as_raw<'a>(&'a self) -> &'a [u8] {
-        unsafe { slice::from_raw_parts(self as *const _ as *const u8,
-                                       mem::size_of::<Self>()) }
-    }
-}
-
-fn show_sizes() {
-    // This isn't panic safe.
-    for min in &[1, 2, 4, 8] {
-        let msize = c::boot_trailer_sz(*min);
-        println!("{:2}: {} (0x{:x})", min, msize, msize);
-    }
-}