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2017-05-22First pass on experimental one-size-fits-nobody keystore.Rob Austein
Support for variable-length keystore objects significantly complicates the keystore implementation, including serious some serious code bloat and a complex recovery algorithm to deal with crashes or loss of power at exactly the wrong time. Perhaps we don't really need this? So this is an experiment to see whether we can replace variable-length keystore objects with fixed-length, perhaps with a compile time option to let us make the fixed object length be 8192 bytes instead of 4096 bytes when needed to hold things like large RSA keys. First pass on this is just throwing away nearly 1,000 lines of excessively complex code. The result probably won't even compile yet, but it's already significantly easier to read.
2017-04-23Avoid deadlock triggered by low-probability race condition.Rob Austein
Static code analysis (Doxygen call graph) detected a low-probability race condition which could have triggered a deadlock on the keystore mutex if the mkmif code returns with an error like HAL_ERROR_CORE_BUSY when we're trying to fetch the KEK. This is a knock-on effect of the awful kludge of backing up the KEK in the keystore flash as an alternative to powering the MKM with a battery as called for in the design. This code path should not exist at all, but, for now, we avoid the deadlock by making it the caller's responsibility to grab the keystore mutex before looking up the KEK.
2017-04-11API cleanup: pkey_open() and pkey_match().Rob Austein
pkey_open() now looks in both keystores rather than requiring the user to know. The chance of collision with randomly-generated UUID is low enough that we really ought to be able to present a single namespace. So now we do. pkey_match() now takes a couple of extra arguments which allow a single search to cover both keystores, as well as matching for specific key flags. The former interface was pretty much useless for anything involving flags, and required the user to issue a separate call for each keystore. User wheel is now exempt from the per-session key lookup constraints, Whether this is a good idea or not is an interesting question, but the whole PKCS #11 derived per-session key thing is weird to begin with, and having keystore listings on the console deliberately ignore session keys was just too confusing.
2017-02-27Track change to stm32 keystore API.Rob Austein
2017-02-14Erase new head of free list in ks_store().Rob Austein
2017-02-13Add some comments for things I figured out while reviewing code.Paul Selkirk
2017-02-02Add locking around keystore operations.Rob Austein
2016-12-21Add hal_ks_init_read_only_pins_only() so bootloader can use PINs.Rob Austein
2016-11-22Clean up ks_set_attributes() a bit.Rob Austein
Fixed handling of deletion actions: code was still using the zero-length attribute convention instead of HAL_PKEY_ATTRIBUTE_NIL. Track existing attributes more closely while copying data from old chunks to new ones in the slow path: the old algorithm had a few dangerous corner cases which could have resulted in the wrong values being written to the new chunks. Single-block-update fast path now under compile-time conditional; in the long run, we probably want this enabled, but it's disabled for now in order to force use and testing of the slow path. This function probably needs to be broken up into a collection of smaller inline functions for readability.
2016-11-21Whack attribute code with a club until it works with PKCS #11.Rob Austein
PKCS #11 supports zero-length attributes (eg, CKA_LABEL) so hack of using zero length attribute as NIL value won't work, instead we use a slightly more portable version of the hack PKCS #11 uses (PKCS #11 stuffs -1 into a CK_ULONG, we stuff 0xFFFFFFFF into a uint32_t). ks_attribute.c code was trying too hard and tripping over its own socks. Instead of trying to maintain attributes[] in place during modification, we now perform the minimum necessary change then re-scan the block. This is (very slightly) slower but more robust, both because the scan code has better error checking and because it's the scan code that we want to be sure is happy before committing a change. Rename hal_rpc_pkey_attribute_t to hal_pkey_attribute_t.
2016-11-19Support queries for attribute length and presence.Rob Austein
Calling hal_rpc_pkey_get_attributes() with attribute_buffer_len = 0 now changes the return behavior so that it reports the lengths of attributes listed in the query, with a length of zero for attributes not present at all. This is mostly to support C_GetAttributeValue() in PKCS #11, but we also use it to make the Python interface a bit kinder to the user.
2016-11-15Allow keystore reinitialization without re-allocating static memory.Rob Austein
Wiping the keystore flash requires reinitializing the keystore, but we don't want to allocate new static memory when we do this.
2016-11-14More API cleanup: remove hal_rpc_pkey_list().Rob Austein
hal_rpc_pkey_list() was a simplistic solution that worked when the keystore only supported a handful of keys and we needed a quick temporary solution in time for a workshop. It doesn't handle large numbers of keys well, and while we could fix that, all of its functionality is now available via more robust API functions, so simplifying the API by deleting it seems best. Since this change required mucking with dispatch vectors yet again, it converts them to use C99 "designated initializer" syntax.
2016-11-10Clean out huge swacks of RPC API we don't need anymore.Rob Austein
pkey attribute API is now just set_attributes() and get_attributes().
2016-11-10First cut at ks_flash support for attribute get/set/delete API.Rob Austein
Passes minimal unit-testing and the same minimal tests report that it does deliver the desired performance speed-up. More testing and much cleanup still needed. Attribute API not quite stable yet, we're probably going to want to remove all the singleton attribute operations from the RPC protocol, and it turns out that ks_delete_attributes() has enough code in common with ks_set_attributes() that it makes more sense to handle the former as a special case of the latter.
2016-11-08First cut at multi-attribute get/set/delete API.Rob Austein
This is not yet complete, only the ks_volatile driver supports it, ks_flash will be a bit more complicated and isn't written yet. At the moment, this adds a complete duplicate set of {set,get,delete}_attributes() functions in parallel to the earlier {set,get,delete}_attribute() functions. We will almost certainly want to get rid of the duplicates, probably (but not necessarily) the entire single-attribute suite. At the moment, though, we want both sets so we can compare execution speeds of the two sets of functions.
2016-11-05ks_list() was returning garbage for keys not visible to current session.Rob Austein
2016-11-03Reorder writing of new chunks in ks_set_attribute().Rob Austein
ks_set_attribute() was written before hal_ks_index_fsck(), and was violating the latter's assumptions for no particularly good reason. Writing out new chunks in the expected order is no more work, and simplifies the consistency checks, so do it that way.
2016-11-01Fix hal_rpc_pkey_match() calling convention.Rob Austein
Old calling sequence didn't quite work, caller had no sane way to know how large the buffer needed to be. Revised sequence is similar to what the PKCS #11 C_FindObject() call does: return the next batch of UUIDs, up to the number specified, end of data indicated by getting back something less than a full block of UUIDs.
2016-11-01Clean out debugging code (flash I/O ring log).Rob Austein
2016-11-01hal_ks_index_fsck() and a pile of debugging code.Rob Austein
The debugging code was for tracking down what turned out to be a race condition in the Alpha's flash driver code (see sw/stm32); much of this was temporary, and will be removed in a (near) future commit, but some of the techniques were useful and belong in the repository in case we need to pull them back for something similar in the future. hal_ks_index_fsck() attempts to diagnose all the things I found wrong in the ks_flash index after one long series of errors. As presently written, it doesn't attempt to fix anything, just diagnose errors: the intent is that we can call this, before and after every modification if necessary, to poinpoint exactly which calls introduce errors. Once things stablize a bit, we may want to crank down the number of calls to this (it's a bit expensive, since it checks the entire index), and perhaps add the ability to clean up whatever errors it might find; the latter might be a good candidate for a CLI command.
2016-10-24Make previous_uuid an input-only argument to hal_rpc_pkey_match().Rob Austein
In retrospect it's obvious that this never needed to be an input/output argument, as its value will always be the same as the last value in the returned array. Doh. So simplify the RPC and call sequence slightly by removing the unnecessary output value.
2016-10-19Shake first round of bugs out of hal_rpc_pkey_match().Rob Austein
The filtering code for this function has not been tested yet.
2016-10-16Debug keystore attribute code; handle name properly in ks_index_replace().Rob Austein
hal_rpc_pkey_match() still untested.
2016-10-14Keystore attribute code. Not really tested.Rob Austein
Passes PKCS #11 "make test" but nothing uses the new attribute code yet. Refactored some of the flash block update code. Attribute code is annoyingly verbose, might be possible to refactor some of that.
2016-10-09Per-session objects in ks_volatile; more untested ks_attribute code.Rob Austein
Mostly this is another checkpoint (still passes PKCS #11 "make test"). ks_volatile.c now contains support for per-session object visibility; this may need more work to support things like a CLI view of all objects regardless of session. Adding this required minor changes to the keystore and pkey APIs, mostly because sessions are per-client. ks_volatile.c also contains an untested first cut at attribute support. Attribute support in ks_flash.c still under construction.
2016-10-07Fix session handle arguments in RPC calls.Rob Austein
RPC calls which pass a pkey handle don't need to pass a session handle, because the session handle is already in the HSM's pkey slot object; pkey RPC calls which don't pass a pkey argument do need to pass a session handle. This change percolates down to the keystore driver, because only the keystore driver knows whether that particular keystore cares about session handles.
2016-10-07Checkpoint along the way to adding keystore attribute support.Rob Austein
This is mostly to archive a commit where PKCS #11 "make test" still works after converting the ks_volatile code to use SDRAM allocated at startup instead of (large) static variables. The attribute code itself is incomplete at this point.
2016-09-30Multi-block object support in keystore.Rob Austein
The main reason for supporting multi-block objects is to allow the PKCS #11 code to attach more attributes than will fit comfortably in a single flash block. This may turn out to be unnecessary once we've fleshed out the attribute storage and retrieval code; if so, we can simplify the code, but this way the keystore won't impose arbitrary (and somewhat inscrutable) size limits on PKCS #11 attributes for large keys. This snapshot passes light testing (PKCS #11 "make test" runs), but the tombstone recovery code in ks_init() is a bit involved, and needs more testing with simulated failures (probably induced under GDB).
2016-09-27Redesign ks_flash block header.Rob Austein
* block_status is now a separate field from block_type, rather than being a composite value. * block_status is checked directly for allowed values in block_read(), and is excluded from the CRC, simplifying the tombstone logic and removing the need for a second CRC field. * Added header fields to allow for objects too large to fit in a single block (8192-bit RSA keys, any key with enough opaque attributes attached). So far this is just the header changes, it's not (yet) full support for multi-block objects.
2016-09-27Write updated PIN block before updating index.Rob Austein
Order of operations is tricky when updating flash blocks, because the process is not atomic and we want to leave the index in a consistent state if something fails.
2016-09-27Add hal_ks_index_replace().Rob Austein
2016-09-26More ks_flash cleanup.Rob Austein
block_read() no longer needs `fast` argument. block_zero() now just zeros first page of block.
2016-09-26Rewrite block_erase_maybe() to run the "maybe" check in constant time.Rob Austein
Running this check in constant time probably isn't necessary, but it plugs a (somewhat far-fetched) timing leak and is easy enough. While we're at this, we also skip the CRC check, which is irrelevant here.
2016-09-23Use subsectors instead of sectors in keystore.Rob Austein
2016-09-16Debug new ks_flash code.Rob Austein
2016-09-16Revised ks_flash. Compiles, not yet tested.Rob Austein
2016-09-13Cleanup prior to rewriting ks_flash.c.Rob Austein
Whack masterkey code to meet libhal coding standards, such as they are. Started layout of new ks_flash data structures but no changes to functions or flash usage yet. MKM initialization from flash placed under compile-time conditional with warning because it's a dangerous kludge that should go away. Started getting rid of obsolete keystore code; ks_mmap.c kept for now, until I get around to merging the useful bits into ks_volatile.
2016-09-12Doh, allow keystore reinitialization after unclean reboot.Rob Austein
2016-09-11Explicit initialization of keystore drivers instead of guessing.Rob Austein
2016-09-09Missed a few instances of type-based key naming in keystore drivers.Rob Austein
2016-09-09Simplify hal_rpc_pkey_find() by removing `type` argument.Rob Austein
Now that key names are UUIDs generated by the HSM, there's no real need to specify type key type when looking up a key, and removing the `type` argument allows a few simplifications of both the internal keystore API and of client code calling the public RPC API.
2016-09-08New keystore index internal API. Compiles, not yet integrated or tested.Rob Austein
2016-09-01Move in-memory keystore from client to server. Whack with club until compiles.Rob Austein
Fixes for various minor issues found while integrating with sw/stm32. Moving the in-memory keystore (PKCS #11 session objects, etc) from the client library to the HSM was on the near term to-do list in any case, doing it now turned out to be the easiest way to solve one of the build problems.
2016-09-01Revised keystore API, part one. Not usable yet.Rob Austein
Changes to implement a revised keystore API. This code probably won't even compile properly yet, and almost certainly will not run, but most of the expected changes are complete at this point. Main points: * Key names are now UUIDs, and are generated by the HSM, not the client. * Keystore API no longer assumes that key database is resident in memory (original API was written on the assumption that the keystore flash would be mapped into the HSM CPU's address space, but apparently the board and flash drivers don't really support that). A few other changes have probably crept in, but the bulk of this changeset is just following through implications of the above, some of which percolate all the way back to the public RPC API.
2016-07-06Return an intelligent error from hal_ks_get_kek.Paul Selkirk
2016-06-24Use hal_error_t as suggested by Rob.Fredrik Thulin
2016-06-23Implement master key for wrapping keys in the keystore.Fredrik Thulin
The KEK (Key Encryption Key) is first fetched from the FPGA that gets it from the volatile Master Key Memory (that in theory has tamper*kek_len = len protection with wiping), and secondly from flash. The flash option is meant for development/evaluation use using an Alpha board where the Master Key Memory is not battery backed. For any serious use of an Alpha, an option is to enter the master key into the volatile MKM on each power-on as a way to unlock the keystore.
2016-06-09some cleanup, and fix delete operationFredrik Thulin
2016-06-09Sort out the redeclaration of HAL_OK with Rob's help.Fredrik Thulin
Thanks Rob!