1 files changed, 47 insertions, 60 deletions

diff --git a/crypto/openssh/auth-rsa.c b/crypto/openssh/auth-rsa.c
index 59bee18..f7ae03c 100644
--- a/crypto/openssh/auth-rsa.c
+++ b/crypto/openssh/auth-rsa.c
@@ -14,7 +14,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: auth-rsa.c,v 1.40 2001/04/06 21:00:07 markus Exp $");
+RCSID("$OpenBSD: auth-rsa.c,v 1.50 2001/12/28 14:50:54 markus Exp $");
 
 #include <openssl/rsa.h>
 #include <openssl/md5.h>
@@ -31,6 +31,7 @@ RCSID("$OpenBSD: auth-rsa.c,v 1.40 2001/04/06 21:00:07 markus Exp $");
 #include "log.h"
 #include "servconf.h"
 #include "auth.h"
+#include "hostfile.h"
 
 /* import */
 extern ServerOptions options;
@@ -65,14 +66,17 @@ auth_rsa_challenge_dialog(RSA *pk)
 	u_char buf[32], mdbuf[16], response[16];
 	MD5_CTX md;
 	u_int i;
-	int plen, len;
+	int len;
 
-	encrypted_challenge = BN_new();
-	challenge = BN_new();
+	if ((encrypted_challenge = BN_new()) == NULL)
+		fatal("auth_rsa_challenge_dialog: BN_new() failed");
+	if ((challenge = BN_new()) == NULL)
+		fatal("auth_rsa_challenge_dialog: BN_new() failed");
 
 	/* Generate a random challenge. */
 	BN_rand(challenge, 256, 0, 0);
-	ctx = BN_CTX_new();
+	if ((ctx = BN_CTX_new()) == NULL)
+		fatal("auth_rsa_challenge_dialog: BN_CTX_new() failed");
 	BN_mod(challenge, challenge, pk->n, ctx);
 	BN_CTX_free(ctx);
 
@@ -87,10 +91,10 @@ auth_rsa_challenge_dialog(RSA *pk)
 	packet_write_wait();
 
 	/* Wait for a response. */
-	packet_read_expect(&plen, SSH_CMSG_AUTH_RSA_RESPONSE);
-	packet_integrity_check(plen, 16, SSH_CMSG_AUTH_RSA_RESPONSE);
+	packet_read_expect(SSH_CMSG_AUTH_RSA_RESPONSE);
 	for (i = 0; i < 16; i++)
 		response[i] = packet_get_char();
+	packet_check_eom();
 
 	/* The response is MD5 of decrypted challenge plus session id. */
 	len = BN_num_bytes(challenge);
@@ -122,13 +126,14 @@ auth_rsa_challenge_dialog(RSA *pk)
 int
 auth_rsa(struct passwd *pw, BIGNUM *client_n)
 {
-	char line[8192], file[MAXPATHLEN];
+	char line[8192], *file;
 	int authenticated;
 	u_int bits;
 	FILE *f;
 	u_long linenum = 0;
 	struct stat st;
-	RSA *pk;
+	Key *key;
+	char *fp;
 
 	/* no user given */
 	if (pw == NULL)
@@ -138,13 +143,14 @@ auth_rsa(struct passwd *pw, BIGNUM *client_n)
 	temporarily_use_uid(pw);
 
 	/* The authorized keys. */
-	snprintf(file, sizeof file, "%.500s/%.100s", pw->pw_dir,
-		 _PATH_SSH_USER_PERMITTED_KEYS);
+	file = authorized_keys_file(pw);
+	debug("trying public RSA key file %s", file);
 
 	/* Fail quietly if file does not exist */
 	if (stat(file, &st) < 0) {
 		/* Restore the privileged uid. */
 		restore_uid();
+		xfree(file);
 		return 0;
 	}
 	/* Open the file containing the authorized keys. */
@@ -154,50 +160,22 @@ auth_rsa(struct passwd *pw, BIGNUM *client_n)
 		restore_uid();
 		packet_send_debug("Could not open %.900s for reading.", file);
 		packet_send_debug("If your home is on an NFS volume, it may need to be world-readable.");
+		xfree(file);
 		return 0;
 	}
-	if (options.strict_modes) {
-		int fail = 0;
-		char buf[1024];
-		/* Check open file in order to avoid open/stat races */
-		if (fstat(fileno(f), &st) < 0 ||
-		    (st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
-		    (st.st_mode & 022) != 0) {
-			snprintf(buf, sizeof buf, "RSA authentication refused for %.100s: "
-				 "bad ownership or modes for '%s'.", pw->pw_name, file);
-			fail = 1;
-		} else {
-			/* Check path to _PATH_SSH_USER_PERMITTED_KEYS */
-			int i;
-			static const char *check[] = {
-				"", _PATH_SSH_USER_DIR, NULL
-			};
-			for (i = 0; check[i]; i++) {
-				snprintf(line, sizeof line, "%.500s/%.100s", pw->pw_dir, check[i]);
-				if (stat(line, &st) < 0 ||
-				    (st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
-				    (st.st_mode & 022) != 0) {
-					snprintf(buf, sizeof buf, "RSA authentication refused for %.100s: "
-						 "bad ownership or modes for '%s'.", pw->pw_name, line);
-					fail = 1;
-					break;
-				}
-			}
-		}
-		if (fail) {
-			fclose(f);
-			log("%s", buf);
-			packet_send_debug("%s", buf);
-			restore_uid();
-			return 0;
-		}
+	if (options.strict_modes &&
+	    secure_filename(f, file, pw, line, sizeof(line)) != 0) {
+		xfree(file);
+		fclose(f);
+		log("Authentication refused: %s", line);
+		packet_send_debug("Authentication refused: %s", line);
+		restore_uid();
+		return 0;
 	}
 	/* Flag indicating whether authentication has succeeded. */
 	authenticated = 0;
 
-	pk = RSA_new();
-	pk->e = BN_new();
-	pk->n = BN_new();
+	key = key_new(KEY_RSA1);
 
 	/*
 	 * Go though the accepted keys, looking for the current key.  If
@@ -235,24 +213,22 @@ auth_rsa(struct passwd *pw, BIGNUM *client_n)
 			options = NULL;
 
 		/* Parse the key from the line. */
-		if (!auth_rsa_read_key(&cp, &bits, pk->e, pk->n)) {
-			debug("%.100s, line %lu: bad key syntax",
-			    file, linenum);
-			packet_send_debug("%.100s, line %lu: bad key syntax",
+		if (hostfile_read_key(&cp, &bits, key) == 0) {
+			debug("%.100s, line %lu: non ssh1 key syntax",
 			    file, linenum);
 			continue;
 		}
 		/* cp now points to the comment part. */
 
 		/* Check if the we have found the desired key (identified by its modulus). */
-		if (BN_cmp(pk->n, client_n) != 0)
+		if (BN_cmp(key->rsa->n, client_n) != 0)
 			continue;
 
 		/* check the real bits  */
-		if (bits != BN_num_bits(pk->n))
-			log("Warning: %s, line %ld: keysize mismatch: "
+		if (bits != BN_num_bits(key->rsa->n))
+			log("Warning: %s, line %lu: keysize mismatch: "
 			    "actual %d vs. announced %d.",
-			    file, linenum, BN_num_bits(pk->n), bits);
+			    file, linenum, BN_num_bits(key->rsa->n), bits);
 
 		/* We have found the desired key. */
 		/*
@@ -263,11 +239,15 @@ auth_rsa(struct passwd *pw, BIGNUM *client_n)
 			continue;
 
 		/* Perform the challenge-response dialog for this key. */
-		if (!auth_rsa_challenge_dialog(pk)) {
+		if (!auth_rsa_challenge_dialog(key->rsa)) {
 			/* Wrong response. */
 			verbose("Wrong response to RSA authentication challenge.");
 			packet_send_debug("Wrong response to RSA authentication challenge.");
-			continue;
+			/*
+			 * Break out of the loop. Otherwise we might send
+			 * another challenge and break the protocol.
+			 */
+			break;
 		}
 		/*
 		 * Correct response.  The client has been successfully
@@ -278,6 +258,12 @@ auth_rsa(struct passwd *pw, BIGNUM *client_n)
 		 * otherwise continue searching.
 		 */
 		authenticated = 1;
+
+	 	fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
+		verbose("Found matching %s key: %s",
+		    key_type(key), fp);
+		xfree(fp);
+
 		break;
 	}
 
@@ -285,9 +271,10 @@ auth_rsa(struct passwd *pw, BIGNUM *client_n)
 	restore_uid();
 
 	/* Close the file. */
+	xfree(file);
 	fclose(f);
 
-	RSA_free(pk);
+	key_free(key);
 
 	if (authenticated)
 		packet_send_debug("RSA authentication accepted.");