This function, and hence rsa_verify(), will perform RSA verification with two essential parameters for a RSA public key in contract of rsa_verify_with_keynode(), which requires additional three parameters stored in FIT image.
It will be used in implementing UEFI secure boot, i.e. image authentication and variable authentication.
Signed-off-by: AKASHI Takahiro takahiro.akashi@linaro.org --- lib/rsa/rsa-verify.c | 57 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 56 insertions(+), 1 deletion(-)
diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c index d2fd0692fa13..3f63bd9c175b 100644 --- a/lib/rsa/rsa-verify.c +++ b/lib/rsa/rsa-verify.c @@ -17,9 +17,14 @@ #include "mkimage.h" #include <fdt_support.h> #endif +#include <linux/kconfig.h> #include <u-boot/rsa-mod-exp.h> #include <u-boot/rsa.h>
+#ifndef __UBOOT__ /* for host tools */ +#undef CONFIG_RSA_VERIFY_WITH_PKEY +#endif + /* Default public exponent for backward compatibility */ #define RSA_DEFAULT_PUBEXP 65537
@@ -270,7 +275,7 @@ out: } #endif
-#if CONFIG_IS_ENABLED(FIT_SIGNATURE) +#if CONFIG_IS_ENABLED(FIT_SIGNATURE) || IS_ENABLED(CONFIG_RSA_VERIFY_WITH_PKEY) /** * rsa_verify_key() - Verify a signature against some data using RSA Key * @@ -344,6 +349,49 @@ static int rsa_verify_key(struct image_sign_info *info, } #endif
+#ifdef CONFIG_RSA_VERIFY_WITH_PKEY +/** + * rsa_verify_with_pkey() - Verify a signature against some data using + * only modulus and exponent as RSA key properties. + * @info: Specifies key information + * @hash: Pointer to the expected hash + * @sig: Signature + * @sig_len: Number of bytes in signature + * + * Parse a RSA public key blob in DER format pointed to in @info and fill + * a key_prop structure with properties of the key. Then verify a RSA PKCS1.5 + * signature against an expected hash using the calculated properties. + * + * Return 0 if verified, -ve on error + */ +static int rsa_verify_with_pkey(struct image_sign_info *info, + const void *hash, uint8_t *sig, uint sig_len) +{ + struct key_prop *prop; + int ret; + + /* Public key is self-described to fill key_prop */ + prop = rsa_gen_key_prop(info->key, info->keylen); + if (!prop) { + debug("Generating necessary parameter for decoding failed\n"); + return -EACCES; + } + + ret = rsa_verify_key(info, prop, sig, sig_len, hash, + info->crypto->key_len); + + rsa_free_key_prop(prop); + + return ret; +} +#else +static int rsa_verify_with_pkey(struct image_sign_info *info, + const void *hash, uint8_t *sig, uint sig_len) +{ + return -EACCES; +} +#endif + #if CONFIG_IS_ENABLED(FIT_SIGNATURE) /** * rsa_verify_with_keynode() - Verify a signature against some data using @@ -434,6 +482,13 @@ int rsa_verify(struct image_sign_info *info, return -EINVAL; }
+ if (IS_ENABLED(CONFIG_RSA_VERIFY_WITH_PKEY) && !info->fdt_blob) { + /* don't rely on fdt properties */ + ret = rsa_verify_with_pkey(info, hash, sig, sig_len); + + return ret; + } + if (CONFIG_IS_ENABLED(FIT_SIGNATURE)) { const void *blob = info->fdt_blob; int ndepth, noffset;