+// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2013, Google Inc.
- *
- * SPDX-License-Identifier: GPL-2.0+
*/
#ifndef USE_HOSTCC
#include <common.h>
#include <fdtdec.h>
+#include <log.h>
+#include <malloc.h>
#include <asm/types.h>
#include <asm/byteorder.h>
-#include <asm/errno.h>
+#include <linux/errno.h>
#include <asm/types.h>
#include <asm/unaligned.h>
#include <dm.h>
#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__
+/*
+ * NOTE:
+ * Since host tools, like mkimage, make use of openssl library for
+ * RSA encryption, rsa_verify_with_pkey()/rsa_gen_key_prop() are
+ * of no use and should not be compiled in.
+ * So just turn off CONFIG_RSA_VERIFY_WITH_PKEY.
+ */
+
+#undef CONFIG_RSA_VERIFY_WITH_PKEY
+#endif
+
/* Default public exponent for backward compatibility */
#define RSA_DEFAULT_PUBEXP 65537
+/**
+ * rsa_verify_padding() - Verify RSA message padding is valid
+ *
+ * Verify a RSA message's padding is consistent with PKCS1.5
+ * padding as described in the RSA PKCS#1 v2.1 standard.
+ *
+ * @msg: Padded message
+ * @pad_len: Number of expected padding bytes
+ * @algo: Checksum algo structure having information on DER encoding etc.
+ * @return 0 on success, != 0 on failure
+ */
+static int rsa_verify_padding(const uint8_t *msg, const int pad_len,
+ struct checksum_algo *algo)
+{
+ int ff_len;
+ int ret;
+
+ /* first byte must be 0x00 */
+ ret = *msg++;
+ /* second byte must be 0x01 */
+ ret |= *msg++ ^ 0x01;
+ /* next ff_len bytes must be 0xff */
+ ff_len = pad_len - algo->der_len - 3;
+ ret |= *msg ^ 0xff;
+ ret |= memcmp(msg, msg+1, ff_len-1);
+ msg += ff_len;
+ /* next byte must be 0x00 */
+ ret |= *msg++;
+ /* next der_len bytes must match der_prefix */
+ ret |= memcmp(msg, algo->der_prefix, algo->der_len);
+
+ return ret;
+}
+
+int padding_pkcs_15_verify(struct image_sign_info *info,
+ uint8_t *msg, int msg_len,
+ const uint8_t *hash, int hash_len)
+{
+ struct checksum_algo *checksum = info->checksum;
+ int ret, pad_len = msg_len - checksum->checksum_len;
+
+ /* Check pkcs1.5 padding bytes. */
+ ret = rsa_verify_padding(msg, pad_len, checksum);
+ if (ret) {
+ debug("In RSAVerify(): Padding check failed!\n");
+ return -EINVAL;
+ }
+
+ /* Check hash. */
+ if (memcmp((uint8_t *)msg + pad_len, hash, msg_len - pad_len)) {
+ debug("In RSAVerify(): Hash check failed!\n");
+ return -EACCES;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_FIT_ENABLE_RSASSA_PSS_SUPPORT
+static void u32_i2osp(uint32_t val, uint8_t *buf)
+{
+ buf[0] = (uint8_t)((val >> 24) & 0xff);
+ buf[1] = (uint8_t)((val >> 16) & 0xff);
+ buf[2] = (uint8_t)((val >> 8) & 0xff);
+ buf[3] = (uint8_t)((val >> 0) & 0xff);
+}
+
+/**
+ * mask_generation_function1() - generate an octet string
+ *
+ * Generate an octet string used to check rsa signature.
+ * It use an input octet string and a hash function.
+ *
+ * @checksum: A Hash function
+ * @seed: Specifies an input variable octet string
+ * @seed_len: Size of the input octet string
+ * @output: Specifies the output octet string
+ * @output_len: Size of the output octet string
+ * @return 0 if the octet string was correctly generated, others on error
+ */
+static int mask_generation_function1(struct checksum_algo *checksum,
+ uint8_t *seed, int seed_len,
+ uint8_t *output, int output_len)
+{
+ struct image_region region[2];
+ int ret = 0, i, i_output = 0, region_count = 2;
+ uint32_t counter = 0;
+ uint8_t buf_counter[4], *tmp;
+ int hash_len = checksum->checksum_len;
+
+ memset(output, 0, output_len);
+
+ region[0].data = seed;
+ region[0].size = seed_len;
+ region[1].data = &buf_counter[0];
+ region[1].size = 4;
+
+ tmp = malloc(hash_len);
+ if (!tmp) {
+ debug("%s: can't allocate array tmp\n", __func__);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ while (i_output < output_len) {
+ u32_i2osp(counter, &buf_counter[0]);
+
+ ret = checksum->calculate(checksum->name,
+ region, region_count,
+ tmp);
+ if (ret < 0) {
+ debug("%s: Error in checksum calculation\n", __func__);
+ goto out;
+ }
+
+ i = 0;
+ while ((i_output < output_len) && (i < hash_len)) {
+ output[i_output] = tmp[i];
+ i_output++;
+ i++;
+ }
+
+ counter++;
+ }
+
+out:
+ free(tmp);
+
+ return ret;
+}
+
+static int compute_hash_prime(struct checksum_algo *checksum,
+ uint8_t *pad, int pad_len,
+ uint8_t *hash, int hash_len,
+ uint8_t *salt, int salt_len,
+ uint8_t *hprime)
+{
+ struct image_region region[3];
+ int ret, region_count = 3;
+
+ region[0].data = pad;
+ region[0].size = pad_len;
+ region[1].data = hash;
+ region[1].size = hash_len;
+ region[2].data = salt;
+ region[2].size = salt_len;
+
+ ret = checksum->calculate(checksum->name, region, region_count, hprime);
+ if (ret < 0) {
+ debug("%s: Error in checksum calculation\n", __func__);
+ goto out;
+ }
+
+out:
+ return ret;
+}
+
+/*
+ * padding_pss_verify() - verify the pss padding of a signature
+ *
+ * Only works with a rsa_pss_saltlen:-2 (default value) right now
+ * saltlen:-1 "set the salt length to the digest length" is currently
+ * not supported.
+ *
+ * @info: Specifies key and FIT information
+ * @msg: byte array of message, len equal to msg_len
+ * @msg_len: Message length
+ * @hash: Pointer to the expected hash
+ * @hash_len: Length of the hash
+ */
+int padding_pss_verify(struct image_sign_info *info,
+ uint8_t *msg, int msg_len,
+ const uint8_t *hash, int hash_len)
+{
+ uint8_t *masked_db = NULL;
+ int masked_db_len = msg_len - hash_len - 1;
+ uint8_t *h = NULL, *hprime = NULL;
+ int h_len = hash_len;
+ uint8_t *db_mask = NULL;
+ int db_mask_len = masked_db_len;
+ uint8_t *db = NULL, *salt = NULL;
+ int db_len = masked_db_len, salt_len = msg_len - hash_len - 2;
+ uint8_t pad_zero[8] = { 0 };
+ int ret, i, leftmost_bits = 1;
+ uint8_t leftmost_mask;
+ struct checksum_algo *checksum = info->checksum;
+
+ /* first, allocate everything */
+ masked_db = malloc(masked_db_len);
+ h = malloc(h_len);
+ db_mask = malloc(db_mask_len);
+ db = malloc(db_len);
+ salt = malloc(salt_len);
+ hprime = malloc(hash_len);
+ if (!masked_db || !h || !db_mask || !db || !salt || !hprime) {
+ printf("%s: can't allocate some buffer\n", __func__);
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* step 4: check if the last byte is 0xbc */
+ if (msg[msg_len - 1] != 0xbc) {
+ printf("%s: invalid pss padding (0xbc is missing)\n", __func__);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* step 5 */
+ memcpy(masked_db, msg, masked_db_len);
+ memcpy(h, msg + masked_db_len, h_len);
+
+ /* step 6 */
+ leftmost_mask = (0xff >> (8 - leftmost_bits)) << (8 - leftmost_bits);
+ if (masked_db[0] & leftmost_mask) {
+ printf("%s: invalid pss padding ", __func__);
+ printf("(leftmost bit of maskedDB not zero)\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* step 7 */
+ mask_generation_function1(checksum, h, h_len, db_mask, db_mask_len);
+
+ /* step 8 */
+ for (i = 0; i < db_len; i++)
+ db[i] = masked_db[i] ^ db_mask[i];
+
+ /* step 9 */
+ db[0] &= 0xff >> leftmost_bits;
+
+ /* step 10 */
+ if (db[0] != 0x01) {
+ printf("%s: invalid pss padding ", __func__);
+ printf("(leftmost byte of db isn't 0x01)\n");
+ ret = EINVAL;
+ goto out;
+ }
+
+ /* step 11 */
+ memcpy(salt, &db[1], salt_len);
+
+ /* step 12 & 13 */
+ compute_hash_prime(checksum, pad_zero, 8,
+ (uint8_t *)hash, hash_len,
+ salt, salt_len, hprime);
+
+ /* step 14 */
+ ret = memcmp(h, hprime, hash_len);
+
+out:
+ free(hprime);
+ free(salt);
+ free(db);
+ free(db_mask);
+ free(h);
+ free(masked_db);
+
+ return ret;
+}
+#endif
+
+#if CONFIG_IS_ENABLED(FIT_SIGNATURE) || CONFIG_IS_ENABLED(RSA_VERIFY_WITH_PKEY)
/**
* rsa_verify_key() - Verify a signature against some data using RSA Key
*
* Verify a RSA PKCS1.5 signature against an expected hash using
* the RSA Key properties in prop structure.
*
+ * @info: Specifies key and FIT information
* @prop: Specifies key
* @sig: Signature
* @sig_len: Number of bytes in signature
* @hash: Pointer to the expected hash
- * @algo: Checksum algo structure having information on RSA padding etc.
+ * @key_len: Number of bytes in rsa key
* @return 0 if verified, -ve on error
*/
-static int rsa_verify_key(struct key_prop *prop, const uint8_t *sig,
+static int rsa_verify_key(struct image_sign_info *info,
+ struct key_prop *prop, const uint8_t *sig,
const uint32_t sig_len, const uint8_t *hash,
- struct checksum_algo *algo)
+ const uint32_t key_len)
{
- const uint8_t *padding;
- int pad_len;
int ret;
#if !defined(USE_HOSTCC)
struct udevice *mod_exp_dev;
#endif
+ struct checksum_algo *checksum = info->checksum;
+ struct padding_algo *padding = info->padding;
+ int hash_len;
- if (!prop || !sig || !hash || !algo)
+ if (!prop || !sig || !hash || !checksum)
return -EIO;
if (sig_len != (prop->num_bits / 8)) {
return -EINVAL;
}
- debug("Checksum algorithm: %s", algo->name);
+ debug("Checksum algorithm: %s", checksum->name);
/* Sanity check for stack size */
if (sig_len > RSA_MAX_SIG_BITS / 8) {
}
uint8_t buf[sig_len];
+ hash_len = checksum->checksum_len;
#if !defined(USE_HOSTCC)
ret = uclass_get_device(UCLASS_MOD_EXP, 0, &mod_exp_dev);
return ret;
}
- padding = algo->rsa_padding;
- pad_len = algo->pad_len - algo->checksum_len;
-
- /* Check pkcs1.5 padding bytes. */
- if (memcmp(buf, padding, pad_len)) {
- debug("In RSAVerify(): Padding check failed!\n");
- return -EINVAL;
+ ret = padding->verify(info, buf, key_len, hash, hash_len);
+ if (ret) {
+ debug("In RSAVerify(): padding check failed!\n");
+ return ret;
}
- /* Check hash. */
- if (memcmp((uint8_t *)buf + pad_len, hash, sig_len - pad_len)) {
- debug("In RSAVerify(): Hash check failed!\n");
- return -EACCES;
+ return 0;
+}
+#endif
+
+#if CONFIG_IS_ENABLED(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
+ */
+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 */
+ ret = rsa_gen_key_prop(info->key, info->keylen, &prop);
+ if (ret) {
+ debug("Generating necessary parameter for decoding failed\n");
+ return ret;
}
- return 0;
+ ret = rsa_verify_key(info, prop, sig, sig_len, hash,
+ info->crypto->key_len);
+
+ rsa_free_key_prop(prop);
+
+ return ret;
+}
+#else
+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
* information in node with prperties of RSA Key like modulus, exponent etc.
struct key_prop prop;
int length;
int ret = 0;
+ const char *algo;
if (node < 0) {
debug("%s: Skipping invalid node", __func__);
return -EBADF;
}
+ algo = fdt_getprop(blob, node, "algo", NULL);
+ if (strcmp(info->name, algo)) {
+ debug("%s: Wrong algo: have %s, expected %s", __func__,
+ info->name, algo);
+ return -EFAULT;
+ }
+
prop.num_bits = fdtdec_get_int(blob, node, "rsa,num-bits", 0);
prop.n0inv = fdtdec_get_int(blob, node, "rsa,n0-inverse", 0);
prop.rr = fdt_getprop(blob, node, "rsa,r-squared", NULL);
- if (!prop.num_bits || !prop.modulus) {
+ if (!prop.num_bits || !prop.modulus || !prop.rr) {
debug("%s: Missing RSA key info", __func__);
return -EFAULT;
}
- ret = rsa_verify_key(&prop, sig, sig_len, hash, info->algo->checksum);
+ ret = rsa_verify_key(info, &prop, sig, sig_len, hash,
+ info->crypto->key_len);
+
+ return ret;
+}
+#else
+static int rsa_verify_with_keynode(struct image_sign_info *info,
+ const void *hash, uint8_t *sig,
+ uint sig_len, int node)
+{
+ return -EACCES;
+}
+#endif
+
+int rsa_verify_hash(struct image_sign_info *info,
+ const uint8_t *hash, uint8_t *sig, uint sig_len)
+{
+ int ret = -EACCES;
+
+ if (CONFIG_IS_ENABLED(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;
+ int sig_node, node;
+ char name[100];
+
+ sig_node = fdt_subnode_offset(blob, 0, FIT_SIG_NODENAME);
+ if (sig_node < 0) {
+ debug("%s: No signature node found\n", __func__);
+ return -ENOENT;
+ }
+
+ /* See if we must use a particular key */
+ if (info->required_keynode != -1) {
+ ret = rsa_verify_with_keynode(info, hash, sig, sig_len,
+ info->required_keynode);
+ return ret;
+ }
+
+ /* Look for a key that matches our hint */
+ snprintf(name, sizeof(name), "key-%s", info->keyname);
+ node = fdt_subnode_offset(blob, sig_node, name);
+ ret = rsa_verify_with_keynode(info, hash, sig, sig_len, node);
+ if (!ret)
+ return ret;
+
+ /* No luck, so try each of the keys in turn */
+ for (ndepth = 0, noffset = fdt_next_node(blob, sig_node,
+ &ndepth);
+ (noffset >= 0) && (ndepth > 0);
+ noffset = fdt_next_node(blob, noffset, &ndepth)) {
+ if (ndepth == 1 && noffset != node) {
+ ret = rsa_verify_with_keynode(info, hash,
+ sig, sig_len,
+ noffset);
+ if (!ret)
+ break;
+ }
+ }
+ }
return ret;
}
const struct image_region region[], int region_count,
uint8_t *sig, uint sig_len)
{
- const void *blob = info->fdt_blob;
/* Reserve memory for maximum checksum-length */
- uint8_t hash[info->algo->checksum->pad_len];
- int ndepth, noffset;
- int sig_node, node;
- char name[100];
+ uint8_t hash[info->crypto->key_len];
int ret;
/*
* Verify that the checksum-length does not exceed the
* rsa-signature-length
*/
- if (info->algo->checksum->checksum_len >
- info->algo->checksum->pad_len) {
+ if (info->checksum->checksum_len >
+ info->crypto->key_len) {
debug("%s: invlaid checksum-algorithm %s for %s\n",
- __func__, info->algo->checksum->name, info->algo->name);
+ __func__, info->checksum->name, info->crypto->name);
return -EINVAL;
}
- sig_node = fdt_subnode_offset(blob, 0, FIT_SIG_NODENAME);
- if (sig_node < 0) {
- debug("%s: No signature node found\n", __func__);
- return -ENOENT;
- }
-
/* Calculate checksum with checksum-algorithm */
- ret = info->algo->checksum->calculate(info->algo->checksum->name,
+ ret = info->checksum->calculate(info->checksum->name,
region, region_count, hash);
if (ret < 0) {
debug("%s: Error in checksum calculation\n", __func__);
return -EINVAL;
}
- /* See if we must use a particular key */
- if (info->required_keynode != -1) {
- ret = rsa_verify_with_keynode(info, hash, sig, sig_len,
- info->required_keynode);
- if (!ret)
- return ret;
- }
-
- /* Look for a key that matches our hint */
- snprintf(name, sizeof(name), "key-%s", info->keyname);
- node = fdt_subnode_offset(blob, sig_node, name);
- ret = rsa_verify_with_keynode(info, hash, sig, sig_len, node);
- if (!ret)
- return ret;
-
- /* No luck, so try each of the keys in turn */
- for (ndepth = 0, noffset = fdt_next_node(info->fit, sig_node, &ndepth);
- (noffset >= 0) && (ndepth > 0);
- noffset = fdt_next_node(info->fit, noffset, &ndepth)) {
- if (ndepth == 1 && noffset != node) {
- ret = rsa_verify_with_keynode(info, hash, sig, sig_len,
- noffset);
- if (!ret)
- break;
- }
- }
-
- return ret;
+ return rsa_verify_hash(info, hash, sig, sig_len);
}
projects / J-u-boot.git / blobdiff