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[ttssh2-commit] [10065] ホスト鍵署名方式として rsa-sha2-256/512 に対応した

• 前の記事 (スレッド) [ttssh2-commit] [10064] 公開鍵形式と公開鍵署名アルゴリズムを分離した
• 次の記事 (スレッド) [ttssh2-commit] [10066] SSH_MSG_EXTINFO を処理するようにした
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Revision: 10065
          https://osdn.net/projects/ttssh2/scm/svn/commits/10065
Author:   doda
Date:     2022-07-18 00:39:21 +0900 (Mon, 18 Jul 2022)
Log Message:
-----------
ホスト鍵署名方式として rsa-sha2-256/512 に対応した

Ticket: #36109

認証鍵での署名方式では未対応。

Ticket Links:
------------
    https://osdn.net/projects/ttssh2/tracker/detail/36109

Modified Paths:
--------------
    trunk/installer/release/TERATERM.INI
    trunk/ttssh2/ttxssh/hostkey.c
    trunk/ttssh2/ttxssh/hostkey.h
    trunk/ttssh2/ttxssh/key.c
    trunk/ttssh2/ttxssh/key.h
    trunk/ttssh2/ttxssh/ssh.c

-------------- next part --------------
Modified: trunk/installer/release/TERATERM.INI
===================================================================
--- trunk/installer/release/TERATERM.INI	2022-07-17 15:39:09 UTC (rev 10064)
+++ trunk/installer/release/TERATERM.INI	2022-07-17 15:39:21 UTC (rev 10065)
@@ -842,8 +842,10 @@
 ;  5...ecdh-sha2-nistp384
 ;  6...ecdh-sha2-nistp521
 ;  7...ssh-ed25519
+;  8...rsa-sha2-256
+;  9...rsa-sha2-512
 ;  0...below this line are disabled.
-HostKeyOrder=4567230
+HostKeyOrder=456798230
 
 ; MAC algorithm order(SSH2)
 ;  1...hmac-sha1

Modified: trunk/ttssh2/ttxssh/hostkey.c
===================================================================
--- trunk/ttssh2/ttxssh/hostkey.c	2022-07-17 15:39:09 UTC (rev 10064)
+++ trunk/ttssh2/ttxssh/hostkey.c	2022-07-17 15:39:21 UTC (rev 10065)
@@ -46,6 +46,8 @@
 	{KEY_ALGO_ECDSA384, KEY_ECDSA384, NID_sha384, "ecdsa-sha2-nistp384"}, // RFC5656
 	{KEY_ALGO_ECDSA521, KEY_ECDSA521, NID_sha512, "ecdsa-sha2-nistp521"}, // RFC5656
 	{KEY_ALGO_ED25519,  KEY_ED25519,  NID_sha512, "ssh-ed25519"},         // RDC8709
+	{KEY_ALGO_RSASHA256,KEY_RSA,      NID_sha256, "rsa-sha2-256"},        // RFC8332
+	{KEY_ALGO_RSASHA512,KEY_RSA,      NID_sha512, "rsa-sha2-512"},        // RFC8332
 	{KEY_ALGO_UNSPEC,   KEY_UNSPEC,   NID_undef,  "ssh-unknown"},
 	{KEY_ALGO_NONE,     KEY_NONE,     NID_undef,  NULL},
 };
@@ -141,7 +143,7 @@
 	return KEY_ALGO_UNSPEC;
 }
 
-int get_ssh2_keyalgo_hashtype(ssh_keyalgo algo)
+int get_ssh2_key_hashtype(ssh_keyalgo algo)
 {
 	const struct ssh2_host_key_t *ptr = ssh2_host_key;
 
@@ -198,6 +200,8 @@
 		KEY_ALGO_ECDSA384,
 		KEY_ALGO_ECDSA521,
 		KEY_ALGO_ED25519,
+		KEY_ALGO_RSASHA256,
+		KEY_ALGO_RSASHA512,
 		KEY_ALGO_RSA,
 		KEY_ALGO_DSA,
 		KEY_ALGO_NONE,

Modified: trunk/ttssh2/ttxssh/hostkey.h
===================================================================
--- trunk/ttssh2/ttxssh/hostkey.h	2022-07-17 15:39:09 UTC (rev 10064)
+++ trunk/ttssh2/ttxssh/hostkey.h	2022-07-17 15:39:21 UTC (rev 10065)
@@ -53,6 +53,8 @@
 	KEY_ALGO_ECDSA384,
 	KEY_ALGO_ECDSA521,
 	KEY_ALGO_ED25519,
+	KEY_ALGO_RSASHA256,
+	KEY_ALGO_RSASHA512,
 	KEY_ALGO_UNSPEC,
 	KEY_ALGO_MAX = KEY_ALGO_UNSPEC,
 } ssh_keyalgo;
@@ -91,7 +93,7 @@
 char *get_ssh2_hostkey_type_name_from_key(Key *key);
 ssh_keyalgo get_ssh2_keyalgo_from_name(const char *name);
 char* get_ssh2_keyalgo_name(ssh_keyalgo algo);
-int get_ssh2_keyalgo_hashtype(ssh_keyalgo algo);
+int get_ssh2_key_hashtype(ssh_keyalgo algo);
 ssh_keytype get_ssh2_keytype_from_keyalgo(ssh_keyalgo algo);
 const char* get_ssh2_keytype_name_from_keyalgo(ssh_keyalgo algo);
 char* get_digest_algorithm_name(digest_algorithm id);

Modified: trunk/ttssh2/ttxssh/key.c
===================================================================
--- trunk/ttssh2/ttxssh/key.c	2022-07-17 15:39:09 UTC (rev 10064)
+++ trunk/ttssh2/ttxssh/key.c	2022-07-17 15:39:21 UTC (rev 10065)
@@ -192,7 +192,38 @@
 	0x05, 0x00, /* NULL */
 	0x04, 0x14  /* Octet string, length 0x14 (20), followed by sha1 hash */
 };
+
 /*
+ * See http://csrc.nist.gov/groups/ST/crypto_apps_infra/csor/algorithms.html
+ * id-sha256 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840)
+ *	organization(1) gov(101) csor(3) nistAlgorithm(4) hashAlgs(2)
+ *	id-sha256(1) }
+ */
+static const u_char id_sha256[] = {
+	0x30, 0x31, /* type Sequence, length 0x31 (49) */
+	0x30, 0x0d, /* type Sequence, length 0x0d (13) */
+	0x06, 0x09, /* type OID, length 0x09 */
+	0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, /* id-sha256 */
+	0x05, 0x00, /* NULL */
+	0x04, 0x20  /* Octet string, length 0x20 (32), followed by sha256 hash */
+};
+
+/*
+ * See http://csrc.nist.gov/groups/ST/crypto_apps_infra/csor/algorithms.html
+ * id-sha512 OBJECT IDENTIFIER ::= { joint-iso-itu-t(2) country(16) us(840)
+ *	organization(1) gov(101) csor(3) nistAlgorithm(4) hashAlgs(2)
+ *	id-sha256(3) }
+ */
+static const u_char id_sha512[] = {
+	0x30, 0x51, /* type Sequence, length 0x51 (81) */
+	0x30, 0x0d, /* type Sequence, length 0x0d (13) */
+	0x06, 0x09, /* type OID, length 0x09 */
+	0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x03, /* id-sha512 */
+	0x05, 0x00, /* NULL */
+	0x04, 0x40  /* Octet string, length 0x40 (64), followed by sha512 hash */
+};
+
+/*
  * id-md5 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
  *	rsadsi(113549) digestAlgorithm(2) 5 }
  */
@@ -225,6 +256,16 @@
 		oidlen = sizeof(id_md5);
 		hlen = 16;
 		break;
+	case NID_sha256:
+		oid = id_sha256;
+		oidlen = sizeof(id_sha256);
+		hlen = 32;
+		break;
+	case NID_sha512:
+		oid = id_sha512;
+		oidlen = sizeof(id_sha512);
+		hlen = 64;
+		break;
 	default:
 		goto done;
 		break;
@@ -269,16 +310,14 @@
 
 int ssh_rsa_verify(RSA *key,
                    u_char *signature, u_int signaturelen,
-                   u_char *data, u_int datalen)
+                   u_char *data, u_int datalen, ssh_keyalgo keyalgo)
 {
 	const EVP_MD *evp_md;
 	EVP_MD_CTX *md = NULL;
-	//	char *ktype;
 	u_char digest[EVP_MAX_MD_SIZE], *sigblob;
 	u_int len, dlen, modlen;
-//	int rlen, ret, nid;
 	int ret = -1, nid;
-	char *ptr;
+	char *ptr, *algo_name;
 	BIGNUM *n;
 
 	md = EVP_MD_CTX_new();
@@ -301,11 +340,13 @@
 	}
 	//debug_print(41, signature, signaturelen);
 	ptr = signature;
+	algo_name = get_ssh2_keyalgo_name(keyalgo);
 
 	// step1
 	len = get_uint32_MSBfirst(ptr);
 	ptr += 4;
-	if (strncmp("ssh-rsa", ptr, len) != 0) {
+	if (strncmp(algo_name, ptr, len) != 0) {
+		logprintf(10, "%s: signature type mismatch: sig: %s, hostkey: %s", __FUNCTION__, ptr, algo_name);
 		ret = -4;
 		goto error;
 	}
@@ -337,11 +378,9 @@
 		len = modlen;
 	}
 
-	/* sha1 the data */
-	//	nid = (datafellows & SSH_BUG_RSASIGMD5) ? NID_md5 : NID_sha1;
-	nid = NID_sha1;
+	nid = get_ssh2_key_hashtype(keyalgo);
 	if ((evp_md = EVP_get_digestbynid(nid)) == NULL) {
-		//error("ssh_rsa_verify: EVP_get_digestbynid %d failed", nid);
+		logprintf(10, "%s: EVP_get_digestbynid %d failed", __FUNCTION__, nid);
 		ret = -6;
 		goto error;
 	}
@@ -521,13 +560,13 @@
 
 int key_verify(Key *key,
                unsigned char *signature, unsigned int signaturelen,
-               unsigned char *data, unsigned int datalen)
+               unsigned char *data, unsigned int datalen, ssh_keyalgo keyalgo)
 {
 	int ret = 0;
 
 	switch (key->type) {
 	case KEY_RSA:
-		ret = ssh_rsa_verify(key->rsa, signature, signaturelen, data, datalen);
+		ret = ssh_rsa_verify(key->rsa, signature, signaturelen, data, datalen, keyalgo);
 		break;
 	case KEY_DSA:
 		ret = ssh_dss_verify(key->dsa, signature, signaturelen, data, datalen);
@@ -2512,8 +2551,9 @@
 
 		sig = buffer_get_string_msg(bsig, &siglen_i);
 		siglen = siglen_i;
-		// Verify signature
-		ret = key_verify(ctx->keys[i], sig, siglen, buffer_ptr(b), buffer_len(b));
+		// \x8E蔲\x82\xAB\x81Bhostkey algorithm \x82\xF0\x8Eg\x82\xA4\x82̂\xCD RSA \x82̎\x9E\x82݂̂Ȃ̂ŁA
+		// \x82Ƃ肠\x82\xA6\x82\xB8 KEY_ALGO_RSA \x82\xF0\x8Ew\x92肵\x82Ă\xA8\x82\xAD\x81B
+		ret = key_verify(ctx->keys[i], sig, siglen, buffer_ptr(b), buffer_len(b), KEY_ALGO_RSA);
 		free(sig);
 		sig = NULL;
 		if (ret != 1) {

Modified: trunk/ttssh2/ttxssh/key.h
===================================================================
--- trunk/ttssh2/ttxssh/key.h	2022-07-17 15:39:09 UTC (rev 10064)
+++ trunk/ttssh2/ttxssh/key.h	2022-07-17 15:39:21 UTC (rev 10065)
@@ -37,7 +37,7 @@
 
 int key_verify(Key *key,
                unsigned char *signature, unsigned int signaturelen,
-               unsigned char *data, unsigned int datalen);
+               unsigned char *data, unsigned int datalen, ssh_keyalgo key_algo);
 RSA *duplicate_RSA(RSA *src);
 DSA *duplicate_DSA(DSA *src);
 unsigned char *duplicate_ED25519_PK(unsigned char *src);

Modified: trunk/ttssh2/ttxssh/ssh.c
===================================================================
--- trunk/ttssh2/ttxssh/ssh.c	2022-07-17 15:39:09 UTC (rev 10064)
+++ trunk/ttssh2/ttxssh/ssh.c	2022-07-17 15:39:21 UTC (rev 10065)
@@ -5446,7 +5446,7 @@
 		}
 	}
 
-	if ((ret = key_verify(hostkey, signature, siglen, hash, hashlen)) != 1) {
+	if ((ret = key_verify(hostkey, signature, siglen, hash, hashlen, pvar->hostkey_type)) != 1) {
 		if (ret == -3 && hostkey->type == KEY_RSA) {
 			if (!pvar->settings.EnableRsaShortKeyServer) {
 				BIGNUM *n;

• 前の記事 (スレッド) [ttssh2-commit] [10064] 公開鍵形式と公開鍵署名アルゴリズムを分離した
• 次の記事 (スレッド) [ttssh2-commit] [10066] SSH_MSG_EXTINFO を処理するようにした
• 記事の並び順: [ 日付 ] [ スレッド ] [ 件名 ] [ 著者 ]