| Message ID | 20210111154137.621732-2-mr.nuke.me@gmail.com |
|---|---|
| State | New |
| Delegated to: | Patrick Delaunay |
| Headers | show |
| Series | Enable ECDSA FIT verification for stm32mp | expand |
Hi Alexandru, On Mon, 11 Jan 2021 at 08:41, Alexandru Gagniuc <mr.nuke.me@gmail.com> wrote: > > Define a UCLASS API for verifying ECDSA signatures. Unlike > UCLASS_MOD_EXP, which focuses strictly on modular exponentiation, > the ECDSA class focuses on verification. This is done so that it > better aligns with mach-specific implementations, such as stm32mp. > > Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> > --- > include/crypto/ecdsa-uclass.h | 39 +++++++++++++++++++++++++++++++++++ > include/dm/uclass-id.h | 1 + > 2 files changed, 40 insertions(+) > create mode 100644 include/crypto/ecdsa-uclass.h This needs a test, as do all uclasses in U-Boot. If it isn't easy to implement the algorithm then I suppose you could fake it by using an easy algorithm like md5, but it does need a test. Regards, Simon
On 1/13/21 10:10 AM, Simon Glass wrote: > Hi Alexandru, > > On Mon, 11 Jan 2021 at 08:41, Alexandru Gagniuc <mr.nuke.me@gmail.com> wrote: >> >> Define a UCLASS API for verifying ECDSA signatures. Unlike >> UCLASS_MOD_EXP, which focuses strictly on modular exponentiation, >> the ECDSA class focuses on verification. This is done so that it >> better aligns with mach-specific implementations, such as stm32mp. >> >> Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> >> --- >> include/crypto/ecdsa-uclass.h | 39 +++++++++++++++++++++++++++++++++++ >> include/dm/uclass-id.h | 1 + >> 2 files changed, 40 insertions(+) >> create mode 100644 include/crypto/ecdsa-uclass.h > > This needs a test, as do all uclasses in U-Boot. If it isn't easy to > implement the algorithm then I suppose you could fake it by using an > easy algorithm like md5, but it does need a test. I agree. I couldn't find a test for UCLASS_MOD_EXP (for guidance), so I'm not sure where to even start. Alex > Regards, > Simon >
Hi Alex, On Thu, 14 Jan 2021 at 09:09, Alex G. <mr.nuke.me@gmail.com> wrote: > > On 1/13/21 10:10 AM, Simon Glass wrote: > > Hi Alexandru, > > > > On Mon, 11 Jan 2021 at 08:41, Alexandru Gagniuc <mr.nuke.me@gmail.com> wrote: > >> > >> Define a UCLASS API for verifying ECDSA signatures. Unlike > >> UCLASS_MOD_EXP, which focuses strictly on modular exponentiation, > >> the ECDSA class focuses on verification. This is done so that it > >> better aligns with mach-specific implementations, such as stm32mp. > >> > >> Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> > >> --- > >> include/crypto/ecdsa-uclass.h | 39 +++++++++++++++++++++++++++++++++++ > >> include/dm/uclass-id.h | 1 + > >> 2 files changed, 40 insertions(+) > >> create mode 100644 include/crypto/ecdsa-uclass.h > > > > This needs a test, as do all uclasses in U-Boot. If it isn't easy to > > implement the algorithm then I suppose you could fake it by using an > > easy algorithm like md5, but it does need a test. > > I agree. I couldn't find a test for UCLASS_MOD_EXP (for guidance), so > I'm not sure where to even start. How about dm_test_rng_read()? That is pretty simple and does a few basic things. Re UCLASS_MOD_EXP this is tested by the vboot tests. It should really have a simple unit test too, though. This is an example of how to add a software implementation of a hardware algorithm. See mod_exp_sw.c Regards, Simon
diff --git a/include/crypto/ecdsa-uclass.h b/include/crypto/ecdsa-uclass.h new file mode 100644 index 0000000000..189843820a --- /dev/null +++ b/include/crypto/ecdsa-uclass.h @@ -0,0 +1,39 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2020, Alexandru Gagniuc <mr.nuke.me@gmail.com> + */ + +#include <dm/device.h> + +/** + * struct ecdsa_public_key - ECDSA public key properties + * + * The struct has pointers to the (x, y) curve coordinates to an ECDSA public + * key, as well as the name of the ECDSA curve. The size of the key is inferred + * from the 'curve_name' + */ +struct ecdsa_public_key { + const char *curve_name; /* Name of curve, e.g. "prime256v1" */ + const void *x; /* x coordinate of public key */ + const void *y; /* y coordinate of public key */ + unsigned int size_bits; /* key size in bits, derived from curve name */ +}; + +struct ecdsa_ops { + /** + * Verify signature of hash against given public key + * + * @dev: ECDSA Device + * @pubkey: ECDSA public key + * @hash: Hash of binary image + * @hash_len: Length of hash in bytes + * @signature: Signature in a raw (R, S) point pair + * @sig_len: Length of signature in bytes + * + * This function verifies that the 'signature' of the given 'hash' was + * signed by the private key corresponding to 'pubkey'. + */ + int (*verify)(struct udevice *dev, const struct ecdsa_public_key *pubkey, + const void *hash, size_t hash_len, + const void *signature, size_t sig_len); +}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index e952a9967c..de4f5db086 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -45,6 +45,7 @@ enum uclass_id { UCLASS_DISPLAY, /* Display (e.g. DisplayPort, HDMI) */ UCLASS_DSI_HOST, /* Display Serial Interface host */ UCLASS_DMA, /* Direct Memory Access */ + UCLASS_ECDSA, /* Elliptic curve cryptographic device */ UCLASS_EFI, /* EFI managed devices */ UCLASS_ETH, /* Ethernet device */ UCLASS_ETH_PHY, /* Ethernet PHY device */
Define a UCLASS API for verifying ECDSA signatures. Unlike UCLASS_MOD_EXP, which focuses strictly on modular exponentiation, the ECDSA class focuses on verification. This is done so that it better aligns with mach-specific implementations, such as stm32mp. Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> --- include/crypto/ecdsa-uclass.h | 39 +++++++++++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + 2 files changed, 40 insertions(+) create mode 100644 include/crypto/ecdsa-uclass.h