From adad6eaac2d03fba830eb1630b5458c1ac7f1907 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Niels=20M=C3=B6ller?= <nisse@lysator.liu.se>
Date: Sun, 3 Jun 2012 22:02:59 +0200
Subject: [PATCH] Changes to pkcs1_signature_prefix interface.
---
ChangeLog | 11 +++++++++++
pkcs1-rsa-md5.c | 28 ++++++++++++++++------------
pkcs1-rsa-sha1.c | 28 ++++++++++++++++------------
pkcs1-rsa-sha256.c | 28 ++++++++++++++++------------
pkcs1-rsa-sha512.c | 29 ++++++++++++++++-------------
pkcs1.c | 25 +++++++++++++------------
pkcs1.h | 4 ++--
rsa-md5-sign.c | 8 ++------
rsa-md5-verify.c | 6 ++----
rsa-sha1-sign.c | 8 ++------
rsa-sha1-verify.c | 6 ++----
rsa-sha256-sign.c | 8 ++------
rsa-sha256-verify.c | 6 ++----
rsa-sha512-sign.c | 8 ++------
rsa-sha512-verify.c | 6 ++----
testsuite/pkcs1-test.c | 2 +-
16 files changed, 107 insertions(+), 104 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 7543e5ac..c2dac593 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2012-06-03 Niels Möller <nisse@lysator.liu.se>
+
+ * testsuite/pkcs1-test.c (test_main): Include leading zero in
+ expected result.
+
+ * pkcs1.c (pkcs1_signature_prefix): Return pointer to where the
+ digest should be written. Let the size input be the key size in
+ octets, rather then key size - 1.
+ * pkcs1-rsa-*.c: Updated for above.
+ * rsa-*-sign.c, rsa-*-verify.c: Pass key->size, not key->size - 1.
+
2012-05-18 Niels Möller <nisse@lysator.liu.se>
* pkcs1-encrypt.c (pkcs1_encrypt): New file and function.
diff --git a/pkcs1-rsa-md5.c b/pkcs1-rsa-md5.c
index 8284f4f2..d9259822 100644
--- a/pkcs1-rsa-md5.c
+++ b/pkcs1-rsa-md5.c
@@ -62,18 +62,20 @@ md5_prefix[] =
};
int
-pkcs1_rsa_md5_encode(mpz_t m, unsigned size, struct md5_ctx *hash)
+pkcs1_rsa_md5_encode(mpz_t m, unsigned key_size, struct md5_ctx *hash)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(md5_prefix),
md5_prefix,
- MD5_DIGEST_SIZE))
+ MD5_DIGEST_SIZE);
+ if (p)
{
- md5_digest(hash, MD5_DIGEST_SIZE, em + size - MD5_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ md5_digest(hash, MD5_DIGEST_SIZE, p);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
@@ -81,18 +83,20 @@ pkcs1_rsa_md5_encode(mpz_t m, unsigned size, struct md5_ctx *hash)
}
int
-pkcs1_rsa_md5_encode_digest(mpz_t m, unsigned size, const uint8_t *digest)
+pkcs1_rsa_md5_encode_digest(mpz_t m, unsigned key_size, const uint8_t *digest)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(md5_prefix),
md5_prefix,
- MD5_DIGEST_SIZE))
+ MD5_DIGEST_SIZE);
+ if (p)
{
- memcpy(em + size - MD5_DIGEST_SIZE, digest, MD5_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ memcpy(p, digest, MD5_DIGEST_SIZE);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
diff --git a/pkcs1-rsa-sha1.c b/pkcs1-rsa-sha1.c
index 78143a77..427a5ade 100644
--- a/pkcs1-rsa-sha1.c
+++ b/pkcs1-rsa-sha1.c
@@ -62,18 +62,20 @@ sha1_prefix[] =
};
int
-pkcs1_rsa_sha1_encode(mpz_t m, unsigned size, struct sha1_ctx *hash)
+pkcs1_rsa_sha1_encode(mpz_t m, unsigned key_size, struct sha1_ctx *hash)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(sha1_prefix),
sha1_prefix,
- SHA1_DIGEST_SIZE))
+ SHA1_DIGEST_SIZE);
+ if (p)
{
- sha1_digest(hash, SHA1_DIGEST_SIZE, em + size - SHA1_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ sha1_digest(hash, SHA1_DIGEST_SIZE, p);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
@@ -81,18 +83,20 @@ pkcs1_rsa_sha1_encode(mpz_t m, unsigned size, struct sha1_ctx *hash)
}
int
-pkcs1_rsa_sha1_encode_digest(mpz_t m, unsigned size, const uint8_t *digest)
+pkcs1_rsa_sha1_encode_digest(mpz_t m, unsigned key_size, const uint8_t *digest)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(sha1_prefix),
sha1_prefix,
- SHA1_DIGEST_SIZE))
+ SHA1_DIGEST_SIZE);
+ if (p)
{
- memcpy(em + size - SHA1_DIGEST_SIZE, digest, SHA1_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ memcpy(p, digest, SHA1_DIGEST_SIZE);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
diff --git a/pkcs1-rsa-sha256.c b/pkcs1-rsa-sha256.c
index a02a3e95..e3f0797d 100644
--- a/pkcs1-rsa-sha256.c
+++ b/pkcs1-rsa-sha256.c
@@ -60,18 +60,20 @@ sha256_prefix[] =
};
int
-pkcs1_rsa_sha256_encode(mpz_t m, unsigned size, struct sha256_ctx *hash)
+pkcs1_rsa_sha256_encode(mpz_t m, unsigned key_size, struct sha256_ctx *hash)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(sha256_prefix),
sha256_prefix,
- SHA256_DIGEST_SIZE))
+ SHA256_DIGEST_SIZE);
+ if (p)
{
- sha256_digest(hash, SHA256_DIGEST_SIZE, em + size - SHA256_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ sha256_digest(hash, SHA256_DIGEST_SIZE, p);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
@@ -79,18 +81,20 @@ pkcs1_rsa_sha256_encode(mpz_t m, unsigned size, struct sha256_ctx *hash)
}
int
-pkcs1_rsa_sha256_encode_digest(mpz_t m, unsigned size, const uint8_t *digest)
+pkcs1_rsa_sha256_encode_digest(mpz_t m, unsigned key_size, const uint8_t *digest)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(sha256_prefix),
sha256_prefix,
- SHA256_DIGEST_SIZE))
+ SHA256_DIGEST_SIZE);
+ if (p)
{
- memcpy(em + size - SHA256_DIGEST_SIZE, digest, SHA256_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ memcpy(p, digest, SHA256_DIGEST_SIZE);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
diff --git a/pkcs1-rsa-sha512.c b/pkcs1-rsa-sha512.c
index df7520e5..ddf62769 100644
--- a/pkcs1-rsa-sha512.c
+++ b/pkcs1-rsa-sha512.c
@@ -60,19 +60,20 @@ sha512_prefix[] =
};
int
-pkcs1_rsa_sha512_encode(mpz_t m, unsigned size, struct sha512_ctx *hash)
+pkcs1_rsa_sha512_encode(mpz_t m, unsigned key_size, struct sha512_ctx *hash)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(sha512_prefix),
sha512_prefix,
- SHA512_DIGEST_SIZE))
+ SHA512_DIGEST_SIZE);
+ if (p)
{
- sha512_digest(hash, SHA512_DIGEST_SIZE,
- em + size - SHA512_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ sha512_digest(hash, SHA512_DIGEST_SIZE, p);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
@@ -80,18 +81,20 @@ pkcs1_rsa_sha512_encode(mpz_t m, unsigned size, struct sha512_ctx *hash)
}
int
-pkcs1_rsa_sha512_encode_digest(mpz_t m, unsigned size, const uint8_t *digest)
+pkcs1_rsa_sha512_encode_digest(mpz_t m, unsigned key_size, const uint8_t *digest)
{
+ uint8_t *p;
TMP_DECL(em, uint8_t, NETTLE_MAX_BIGNUM_SIZE);
- TMP_ALLOC(em, size);
+ TMP_ALLOC(em, key_size);
- if (pkcs1_signature_prefix(size, em,
+ p = pkcs1_signature_prefix(key_size, em,
sizeof(sha512_prefix),
sha512_prefix,
- SHA512_DIGEST_SIZE))
+ SHA512_DIGEST_SIZE);
+ if (p)
{
- memcpy(em + size - SHA512_DIGEST_SIZE, digest, SHA512_DIGEST_SIZE);
- nettle_mpz_set_str_256_u(m, size, em);
+ memcpy(p, digest, SHA512_DIGEST_SIZE);
+ nettle_mpz_set_str_256_u(m, key_size, em);
return 1;
}
else
diff --git a/pkcs1.c b/pkcs1.c
index 757017f9..4b73d35c 100644
--- a/pkcs1.c
+++ b/pkcs1.c
@@ -34,13 +34,13 @@
/* Formats the PKCS#1 padding, of the form
*
- * 0x01 0xff ... 0xff 0x00 id ...digest...
+ * 0x00 0x01 0xff ... 0xff 0x00 id ...digest...
*
* where the 0xff ... 0xff part consists of at least 8 octets. The
- * total size should be one less than the octet size of n.
+ * total size equals the octet size of n.
*/
-int
-pkcs1_signature_prefix(unsigned size,
+uint8_t *
+pkcs1_signature_prefix(unsigned key_size,
uint8_t *buffer,
unsigned id_size,
const uint8_t *id,
@@ -48,17 +48,18 @@ pkcs1_signature_prefix(unsigned size,
{
unsigned j;
- if (size < 10 + id_size + digest_size)
- return 0;
+ if (key_size < 11 + id_size + digest_size)
+ return NULL;
- j = size - digest_size - id_size;
+ j = key_size - digest_size - id_size;
memcpy (buffer + j, id, id_size);
- buffer[0] = 1;
- buffer[--j] = 0;
+ buffer[0] = 0;
+ buffer[1] = 1;
+ buffer[j-1] = 0;
- assert(j >= 9);
- memset(buffer + 1, 0xff, j - 1);
+ assert(j >= 11);
+ memset(buffer + 2, 0xff, j - 3);
- return 1;
+ return buffer + j + id_size;
}
diff --git a/pkcs1.h b/pkcs1.h
index 68de0b7d..2f6251e2 100644
--- a/pkcs1.h
+++ b/pkcs1.h
@@ -51,8 +51,8 @@ struct sha1_ctx;
struct sha256_ctx;
struct sha512_ctx;
-int
-pkcs1_signature_prefix(unsigned size,
+uint8_t *
+pkcs1_signature_prefix(unsigned key_size,
uint8_t *buffer,
unsigned id_size,
const uint8_t *id,
diff --git a/rsa-md5-sign.c b/rsa-md5-sign.c
index f13ce064..fbd433c7 100644
--- a/rsa-md5-sign.c
+++ b/rsa-md5-sign.c
@@ -39,9 +39,7 @@ rsa_md5_sign(const struct rsa_private_key *key,
struct md5_ctx *hash,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_md5_encode(s, key->size - 1, hash))
+ if (pkcs1_rsa_md5_encode(s, key->size, hash))
{
rsa_compute_root(key, s, s);
return 1;
@@ -58,9 +56,7 @@ rsa_md5_sign_digest(const struct rsa_private_key *key,
const uint8_t *digest,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_md5_encode_digest(s, key->size - 1, digest))
+ if (pkcs1_rsa_md5_encode_digest(s, key->size, digest))
{
rsa_compute_root(key, s, s);
return 1;
diff --git a/rsa-md5-verify.c b/rsa-md5-verify.c
index 3de12158..0e9bcc1e 100644
--- a/rsa-md5-verify.c
+++ b/rsa-md5-verify.c
@@ -42,10 +42,9 @@ rsa_md5_verify(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_md5_encode(m, key->size - 1, hash)
+ res = (pkcs1_rsa_md5_encode(m, key->size, hash)
&& _rsa_verify(key, m, s));
mpz_clear(m);
@@ -61,10 +60,9 @@ rsa_md5_verify_digest(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_md5_encode_digest(m, key->size - 1, digest)
+ res = (pkcs1_rsa_md5_encode_digest(m, key->size, digest)
&& _rsa_verify(key, m, s));
mpz_clear(m);
diff --git a/rsa-sha1-sign.c b/rsa-sha1-sign.c
index aad9879b..0f138f85 100644
--- a/rsa-sha1-sign.c
+++ b/rsa-sha1-sign.c
@@ -39,9 +39,7 @@ rsa_sha1_sign(const struct rsa_private_key *key,
struct sha1_ctx *hash,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_sha1_encode(s, key->size - 1, hash))
+ if (pkcs1_rsa_sha1_encode(s, key->size, hash))
{
rsa_compute_root(key, s, s);
return 1;
@@ -58,9 +56,7 @@ rsa_sha1_sign_digest(const struct rsa_private_key *key,
const uint8_t *digest,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_sha1_encode_digest(s, key->size - 1, digest))
+ if (pkcs1_rsa_sha1_encode_digest(s, key->size, digest))
{
rsa_compute_root(key, s, s);
return 1;
diff --git a/rsa-sha1-verify.c b/rsa-sha1-verify.c
index 90f01f68..8624e749 100644
--- a/rsa-sha1-verify.c
+++ b/rsa-sha1-verify.c
@@ -42,10 +42,9 @@ rsa_sha1_verify(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_sha1_encode(m, key->size - 1, hash)
+ res = (pkcs1_rsa_sha1_encode(m, key->size, hash)
&& _rsa_verify(key, m, s));
mpz_clear(m);
@@ -61,10 +60,9 @@ rsa_sha1_verify_digest(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_sha1_encode_digest(m, key->size - 1, digest)
+ res = (pkcs1_rsa_sha1_encode_digest(m, key->size, digest)
&& _rsa_verify(key, m, s));
mpz_clear(m);
diff --git a/rsa-sha256-sign.c b/rsa-sha256-sign.c
index 0af12c94..30ba497a 100644
--- a/rsa-sha256-sign.c
+++ b/rsa-sha256-sign.c
@@ -39,9 +39,7 @@ rsa_sha256_sign(const struct rsa_private_key *key,
struct sha256_ctx *hash,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_sha256_encode(s, key->size - 1, hash))
+ if (pkcs1_rsa_sha256_encode(s, key->size, hash))
{
rsa_compute_root(key, s, s);
return 1;
@@ -58,9 +56,7 @@ rsa_sha256_sign_digest(const struct rsa_private_key *key,
const uint8_t *digest,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_sha256_encode_digest(s, key->size - 1, digest))
+ if (pkcs1_rsa_sha256_encode_digest(s, key->size, digest))
{
rsa_compute_root(key, s, s);
return 1;
diff --git a/rsa-sha256-verify.c b/rsa-sha256-verify.c
index ed8f7d0c..cfb6afb4 100644
--- a/rsa-sha256-verify.c
+++ b/rsa-sha256-verify.c
@@ -42,10 +42,9 @@ rsa_sha256_verify(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_sha256_encode(m, key->size - 1, hash)
+ res = (pkcs1_rsa_sha256_encode(m, key->size, hash)
&&_rsa_verify(key, m, s));
mpz_clear(m);
@@ -61,10 +60,9 @@ rsa_sha256_verify_digest(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_sha256_encode_digest(m, key->size - 1, digest)
+ res = (pkcs1_rsa_sha256_encode_digest(m, key->size, digest)
&& _rsa_verify(key, m, s));
mpz_clear(m);
diff --git a/rsa-sha512-sign.c b/rsa-sha512-sign.c
index a8ab9810..cf2047ef 100644
--- a/rsa-sha512-sign.c
+++ b/rsa-sha512-sign.c
@@ -39,9 +39,7 @@ rsa_sha512_sign(const struct rsa_private_key *key,
struct sha512_ctx *hash,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_sha512_encode(s, key->size - 1, hash))
+ if (pkcs1_rsa_sha512_encode(s, key->size, hash))
{
rsa_compute_root(key, s, s);
return 1;
@@ -58,9 +56,7 @@ rsa_sha512_sign_digest(const struct rsa_private_key *key,
const uint8_t *digest,
mpz_t s)
{
- assert(key->size > 0);
-
- if (pkcs1_rsa_sha512_encode_digest(s, key->size - 1, digest))
+ if (pkcs1_rsa_sha512_encode_digest(s, key->size, digest))
{
rsa_compute_root(key, s, s);
return 1;
diff --git a/rsa-sha512-verify.c b/rsa-sha512-verify.c
index 0fca6b87..90f82347 100644
--- a/rsa-sha512-verify.c
+++ b/rsa-sha512-verify.c
@@ -42,10 +42,9 @@ rsa_sha512_verify(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_sha512_encode(m, key->size - 1, hash)
+ res = (pkcs1_rsa_sha512_encode(m, key->size, hash)
&& _rsa_verify(key, m, s));
mpz_clear(m);
@@ -61,10 +60,9 @@ rsa_sha512_verify_digest(const struct rsa_public_key *key,
int res;
mpz_t m;
- assert(key->size > 0);
mpz_init(m);
- res = (pkcs1_rsa_sha512_encode_digest(m, key->size - 1, digest)
+ res = (pkcs1_rsa_sha512_encode_digest(m, key->size, digest)
&& _rsa_verify(key, m, s));
mpz_clear(m);
diff --git a/testsuite/pkcs1-test.c b/testsuite/pkcs1-test.c
index 283e742e..a0521b03 100644
--- a/testsuite/pkcs1-test.c
+++ b/testsuite/pkcs1-test.c
@@ -6,7 +6,7 @@ int
test_main(void)
{
uint8_t buffer[16];
- uint8_t expected[16] = { 1, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+ uint8_t expected[16] = { 0, 1, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0, 'a', 'b', 'c' };
pkcs1_signature_prefix(sizeof(buffer), buffer,
--
GitLab