1 files changed, 309 insertions, 0 deletions

diff --git a/other/openssh-reverse/dsa.c b/other/openssh-reverse/dsa.c
new file mode 100644
index 0000000..c1c37bc
--- /dev/null
+++ b/other/openssh-reverse/dsa.c
@@ -0,0 +1,309 @@
+/*
+ * Copyright (c) 2000 Markus Friedl.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by Markus Friedl.
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: dsa.c,v 1.9 2000/06/20 01:39:41 markus Exp $");
+
+#include "ssh.h"
+#include "xmalloc.h"
+#include "buffer.h"
+#include "bufaux.h"
+#include "compat.h"
+
+#include <openssl/bn.h>
+#include <openssl/dh.h>
+#include <openssl/rsa.h>
+#include <openssl/dsa.h>
+#include <openssl/evp.h>
+#include <openssl/bio.h>
+#include <openssl/pem.h>
+
+#include <openssl/hmac.h>
+#include "kex.h"
+#include "key.h"
+#include "uuencode.h"
+
+#define INTBLOB_LEN     20
+#define SIGBLOB_LEN     (2*INTBLOB_LEN)
+
+Key *
+dsa_key_from_blob(
+    char *blob, int blen)
+{
+        Buffer b;
+        char *ktype;
+        int rlen;
+        DSA *dsa;
+        Key *key;
+
+#ifdef DEBUG_DSS
+        dump_base64(stderr, blob, blen);
+#endif
+        /* fetch & parse DSA/DSS pubkey */
+        key = key_new(KEY_DSA);
+        dsa = key->dsa;
+        buffer_init(&b);
+        buffer_append(&b, blob, blen);
+        ktype = buffer_get_string(&b, NULL);
+        if (strcmp(KEX_DSS, ktype) != 0) {
+                error("dsa_key_from_blob: cannot handle type %s", ktype);
+                key_free(key);
+                return NULL;
+        }
+        buffer_get_bignum2(&b, dsa->p);
+        buffer_get_bignum2(&b, dsa->q);
+        buffer_get_bignum2(&b, dsa->g);
+        buffer_get_bignum2(&b, dsa->pub_key);
+        rlen = buffer_len(&b);
+        if(rlen != 0)
+                error("dsa_key_from_blob: remaining bytes in key blob %d", rlen);
+        buffer_free(&b);
+
+        debug("keytype %s", ktype);
+#ifdef DEBUG_DSS
+        DSA_print_fp(stderr, dsa, 8);
+#endif
+        return key;
+}
+int
+dsa_make_key_blob(Key *key, unsigned char **blobp, unsigned int *lenp)
+{
+        Buffer b;
+        int len;
+        unsigned char *buf;
+
+        if (key == NULL || key->type != KEY_DSA)
+                return 0;
+        buffer_init(&b);
+        buffer_put_cstring(&b, KEX_DSS);
+        buffer_put_bignum2(&b, key->dsa->p);
+        buffer_put_bignum2(&b, key->dsa->q);
+        buffer_put_bignum2(&b, key->dsa->g);
+        buffer_put_bignum2(&b, key->dsa->pub_key);
+        len = buffer_len(&b);
+        buf = xmalloc(len);
+        memcpy(buf, buffer_ptr(&b), len);
+        memset(buffer_ptr(&b), 0, len);
+        buffer_free(&b);
+        if (lenp != NULL)
+                *lenp = len;
+        if (blobp != NULL)
+                *blobp = buf;
+        return len;
+}
+int
+dsa_sign(
+    Key *key,
+    unsigned char **sigp, int *lenp,
+    unsigned char *data, int datalen)
+{
+        unsigned char *digest;
+        unsigned char *ret;
+        DSA_SIG *sig;
+        EVP_MD *evp_md = EVP_sha1();
+        EVP_MD_CTX md;
+        unsigned int rlen;
+        unsigned int slen;
+        unsigned int len;
+        unsigned char sigblob[SIGBLOB_LEN];
+        Buffer b;
+
+        if (key == NULL || key->type != KEY_DSA || key->dsa == NULL) {
+                error("dsa_sign: no DSA key");
+                return -1;
+        }
+        digest = xmalloc(evp_md->md_size);
+        EVP_DigestInit(&md, evp_md);
+        EVP_DigestUpdate(&md, data, datalen);
+        EVP_DigestFinal(&md, digest, NULL);
+
+        sig = DSA_do_sign(digest, evp_md->md_size, key->dsa);
+        if (sig == NULL) {
+                fatal("dsa_sign: cannot sign");
+        }
+
+        rlen = BN_num_bytes(sig->r);
+        slen = BN_num_bytes(sig->s);
+        if (rlen > INTBLOB_LEN || slen > INTBLOB_LEN) {
+                error("bad sig size %d %d", rlen, slen);
+                DSA_SIG_free(sig);
+                return -1;
+        }
+        debug("sig size %d %d", rlen, slen);
+
+        memset(sigblob, 0, SIGBLOB_LEN);
+        BN_bn2bin(sig->r, sigblob+ SIGBLOB_LEN - INTBLOB_LEN - rlen);
+        BN_bn2bin(sig->s, sigblob+ SIGBLOB_LEN - slen);
+        DSA_SIG_free(sig);
+
+        if (datafellows & SSH_BUG_SIGBLOB) {
+                debug("datafellows");
+                ret = xmalloc(SIGBLOB_LEN);
+                memcpy(ret, sigblob, SIGBLOB_LEN);
+                if (lenp != NULL)
+                        *lenp = SIGBLOB_LEN;
+                if (sigp != NULL)
+                        *sigp = ret;
+        } else {
+                /* ietf-drafts */
+                buffer_init(&b);
+                buffer_put_cstring(&b, KEX_DSS);
+                buffer_put_string(&b, sigblob, SIGBLOB_LEN);
+                len = buffer_len(&b);
+                ret = xmalloc(len);
+                memcpy(ret, buffer_ptr(&b), len);
+                buffer_free(&b);
+                if (lenp != NULL)
+                        *lenp = len;
+                if (sigp != NULL)
+                        *sigp = ret;
+        }
+        return 0;
+}
+int
+dsa_verify(
+    Key *key,
+    unsigned char *signature, int signaturelen,
+    unsigned char *data, int datalen)
+{
+        Buffer b;
+        unsigned char *digest;
+        DSA_SIG *sig;
+        EVP_MD *evp_md = EVP_sha1();
+        EVP_MD_CTX md;
+        unsigned char *sigblob;
+        char *txt;
+        unsigned int len;
+        int rlen;
+        int ret;
+
+        if (key == NULL || key->type != KEY_DSA || key->dsa == NULL) {
+                error("dsa_verify: no DSA key");
+                return -1;
+        }
+
+        if (!(datafellows & SSH_BUG_SIGBLOB) &&
+            signaturelen == SIGBLOB_LEN) {
+                datafellows |= ~SSH_BUG_SIGBLOB;
+                log("autodetect SSH_BUG_SIGBLOB");
+        } else if ((datafellows & SSH_BUG_SIGBLOB) &&
+            signaturelen != SIGBLOB_LEN) {
+                log("autoremove SSH_BUG_SIGBLOB");
+                datafellows &= ~SSH_BUG_SIGBLOB;
+        }
+
+        debug("len %d datafellows %d", signaturelen, datafellows);
+
+        /* fetch signature */
+        if (datafellows & SSH_BUG_SIGBLOB) {
+                sigblob = signature;
+                len = signaturelen;
+        } else {
+                /* ietf-drafts */
+                char *ktype;
+                buffer_init(&b);
+                buffer_append(&b, (char *) signature, signaturelen);
+                ktype = buffer_get_string(&b, NULL);
+                if (strcmp(KEX_DSS, ktype) != 0) {
+                        error("dsa_verify: cannot handle type %s", ktype);
+                        buffer_free(&b);
+                        return -1;
+                }
+                sigblob = (unsigned char *)buffer_get_string(&b, &len);
+                rlen = buffer_len(&b);
+                if(rlen != 0) {
+                        error("remaining bytes in signature %d", rlen);
+                        buffer_free(&b);
+                        return -1;
+                }
+                buffer_free(&b);
+                xfree(ktype);
+        }
+
+        if (len != SIGBLOB_LEN) {
+                fatal("bad sigbloblen %d != SIGBLOB_LEN", len);
+        }
+
+        /* parse signature */
+        sig = DSA_SIG_new();
+        sig->r = BN_new();
+        sig->s = BN_new();
+        BN_bin2bn(sigblob, INTBLOB_LEN, sig->r);
+        BN_bin2bn(sigblob+ INTBLOB_LEN, INTBLOB_LEN, sig->s);
+
+        if (!(datafellows & SSH_BUG_SIGBLOB)) {
+                memset(sigblob, 0, len);
+                xfree(sigblob);
+        }
+        
+        /* sha1 the data */
+        digest = xmalloc(evp_md->md_size);
+        EVP_DigestInit(&md, evp_md);
+        EVP_DigestUpdate(&md, data, datalen);
+        EVP_DigestFinal(&md, digest, NULL);
+
+        ret = DSA_do_verify(digest, evp_md->md_size, sig, key->dsa);
+
+        memset(digest, 0, evp_md->md_size);
+        xfree(digest);
+        DSA_SIG_free(sig);
+
+        switch (ret) {
+        case 1:
+                txt = "correct";
+                break;
+        case 0:
+                txt = "incorrect";
+                break;
+        case -1:
+        default:
+                txt = "error";
+                break;
+        }
+        debug("dsa_verify: signature %s", txt);
+        return ret;
+}
+
+Key *
+dsa_generate_key(unsigned int bits)
+{
+        DSA *dsa = DSA_generate_parameters(bits, NULL, 0, NULL, NULL, NULL, NULL);
+        Key *k;
+        if (dsa == NULL) {
+                fatal("DSA_generate_parameters failed");
+        }
+        if (!DSA_generate_key(dsa)) {
+                fatal("DSA_generate_keys failed");
+        }
+
+        k = key_new(KEY_EMPTY);
+        k->type = KEY_DSA;
+        k->dsa = dsa;
+        return k;
+}