fdt_add_bignum() is useful for algorithms other than just RSA. To
allow its use for ECDSA, move it to a common file under lib/.
The new file is suffixed with '-libcrypto' because it has a direct
dependency on openssl. This is due to the use of the "BIGNUM *" type.
Signed-off-by: Alexandru Gagniuc
---
include/u-boot/fdt-libcrypto.h | 27 +
lib/fdt-libcrypto.c| 72 ++
lib/rsa/rsa-sign.c | 65 +-
tools/Makefile | 1 +
4 files changed, 101 insertions(+), 64 deletions(-)
create mode 100644 include/u-boot/fdt-libcrypto.h
create mode 100644 lib/fdt-libcrypto.c
diff --git a/include/u-boot/fdt-libcrypto.h b/include/u-boot/fdt-libcrypto.h
new file mode 100644
index 00..5142f37039
--- /dev/null
+++ b/include/u-boot/fdt-libcrypto.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2020, Alexandru Gagniuc
+ * Copyright (c) 2013, Google Inc.
+ */
+
+#ifndef _FDT_LIBCRYPTO_H
+#define _FDT_LIBCRYPTO_H
+
+#include
+
+/**
+ * fdt_add_bignum() - Write a libcrypto BIGNUM as an FDT property
+ *
+ * Convert a libcrypto BIGNUM * into a big endian array of integers.
+ *
+ * @blob: FDT blob to modify
+ * @noffset: Offset of the FDT node
+ * @prop_name: What to call the property in the FDT
+ * @num: pointer to a libcrypto big number
+ * @num_bits: How big is 'num' in bits?
+ * @return 0 if all good all working, -ve on horror
+ */
+int fdt_add_bignum(void *blob, int noffset, const char *prop_name,
+ BIGNUM *num, int num_bits);
+
+#endif /* _FDT_LIBCRYPTO_H */
diff --git a/lib/fdt-libcrypto.c b/lib/fdt-libcrypto.c
new file mode 100644
index 00..ecb0344c8f
--- /dev/null
+++ b/lib/fdt-libcrypto.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2020, Alexandru Gagniuc
+ * Copyright (c) 2013, Google Inc.
+ */
+
+#include
+#include
+
+int fdt_add_bignum(void *blob, int noffset, const char *prop_name,
+ BIGNUM *num, int num_bits)
+{
+ int nwords = num_bits / 32;
+ int size;
+ uint32_t *buf, *ptr;
+ BIGNUM *tmp, *big2, *big32, *big2_32;
+ BN_CTX *ctx;
+ int ret;
+
+ tmp = BN_new();
+ big2 = BN_new();
+ big32 = BN_new();
+ big2_32 = BN_new();
+
+ /*
+* Note: This code assumes that all of the above succeed, or all fail.
+* In practice memory allocations generally do not fail (unless the
+* process is killed), so it does not seem worth handling each of these
+* as a separate case. Technicaly this could leak memory on failure,
+* but a) it won't happen in practice, and b) it doesn't matter as we
+* will immediately exit with a failure code.
+*/
+ if (!tmp || !big2 || !big32 || !big2_32) {
+ fprintf(stderr, "Out of memory (bignum)\n");
+ return -ENOMEM;
+ }
+ ctx = BN_CTX_new();
+ if (!ctx) {
+ fprintf(stderr, "Out of memory (bignum context)\n");
+ return -ENOMEM;
+ }
+ BN_set_word(big2, 2L);
+ BN_set_word(big32, 32L);
+ BN_exp(big2_32, big2, big32, ctx); /* B = 2^32 */
+
+ size = nwords * sizeof(uint32_t);
+ buf = malloc(size);
+ if (!buf) {
+ fprintf(stderr, "Out of memory (%d bytes)\n", size);
+ return -ENOMEM;
+ }
+
+ /* Write out modulus as big endian array of integers */
+ for (ptr = buf + nwords - 1; ptr >= buf; ptr--) {
+ BN_mod(tmp, num, big2_32, ctx); /* n = N mod B */
+ *ptr = cpu_to_fdt32(BN_get_word(tmp));
+ BN_rshift(num, num, 32); /* N = N/B */
+ }
+
+ /*
+* We try signing with successively increasing size values, so this
+* might fail several times
+*/
+ ret = fdt_setprop(blob, noffset, prop_name, buf, size);
+ free(buf);
+ BN_free(tmp);
+ BN_free(big2);
+ BN_free(big32);
+ BN_free(big2_32);
+
+ return ret ? -FDT_ERR_NOSPACE : 0;
+}
diff --git a/lib/rsa/rsa-sign.c b/lib/rsa/rsa-sign.c
index 1f0d81bd7a..557c690a6d 100644
--- a/lib/rsa/rsa-sign.c
+++ b/lib/rsa/rsa-sign.c
@@ -9,6 +9,7 @@
#include
#include
#include
+#include
#include
#include
#include
@@ -680,70 +681,6 @@ int rsa_get_params(RSA *key, uint64_t *exponent, uint32_t
*n0_invp,
return ret;
}
-static int fdt_add_bignum(void *blob, int noffset, const char *prop_name,
- BIGNUM *num, int num_bits)
-{
- int nwords = num_bits / 32;
- int size;
- uint32_t *buf, *ptr;
- BIGNUM *tmp, *big2, *big32, *big2_32;
- BN_CTX *ctx;
- int ret;
-
- tmp = BN_new();
- big2 = BN_new();
- big32 = BN_new();
- big2_32 = BN_new();
-
- /*
-* Note: This code assumes that all of the above succeed, or all fail.
-* In practice
