- OpenBSD CVS Changes

   - [canohost.c]
     fix get_remote_port() and friends for sshd -i;
     Holger.Trapp@Informatik.TU-Chemnitz.DE
   - [mpaux.c]
     make code simpler. no need for memcpy. niels@ ok
   - [pty.c]
     namebuflen not sizeof namebuflen; bnd@ep-ag.com via djm@mindrot.org
     fix proto; markus
   - [ssh.1]
      typo; mark.baushke@solipsa.com
   - [channels.c ssh.c ssh.h sshd.c]
     type conflict for 'extern Type *options' in channels.c; dot@dotat.at
   - [sshconnect.c]
     move checking of hostkey into own function.
   - [version.h]
     OpenSSH-1.2.1

1 files changed, 135 insertions, 111 deletions

diff --git a/sshconnect.c b/sshconnect.c
index e6175f11b..d96f8e026 100644
--- a/sshconnect.c
+++ b/sshconnect.c
@@ -8,7 +8,7 @@
  */
 
 #include "includes.h"
-RCSID("$Id: sshconnect.c,v 1.17 1999/12/07 04:38:32 damien Exp $");
+RCSID("$Id: sshconnect.c,v 1.18 1999/12/13 23:47:16 damien Exp $");
 
 #ifdef HAVE_OPENSSL
 #include <openssl/bn.h>
@@ -156,8 +156,10 @@ ssh_create_socket(uid_t original_real_uid, int privileged)
                         fatal("rresvport: %.100s", strerror(errno));
                 debug("Allocated local port %d.", p);
         } else {
-                /* Just create an ordinary socket on arbitrary port.  We
-                   use the user's uid to create the socket. */
+                /*
+                 * Just create an ordinary socket on arbitrary port.  We use
+                 * the user's uid to create the socket.
+                 */
                 temporarily_use_uid(original_real_uid);
                 sock = socket(AF_INET, SOCK_STREAM, 0);
                 if (sock < 0)
@@ -209,9 +211,11 @@ ssh_connect(const char *host, struct sockaddr_in * hostaddr,
         /* No host lookup made yet. */
         hp = NULL;
 
-        /* Try to connect several times.  On some machines, the first time
-           will sometimes fail.  In general socket code appears to behave
-           quite magically on many machines. */
+        /*
+         * Try to connect several times.  On some machines, the first time
+         * will sometimes fail.  In general socket code appears to behave
+         * quite magically on many machines.
+         */
         for (attempt = 0; attempt < connection_attempts; attempt++) {
                 if (attempt > 0)
                         debug("Trying again...");
@@ -1087,39 +1091,21 @@ read_yes_or_no(const char *prompt, int defval)
 }
 
 /*
- * Starts a dialog with the server, and authenticates the current user on the
- * server.  This does not need any extra privileges.  The basic connection
- * to the server must already have been established before this is called.
- * User is the remote user; if it is NULL, the current local user name will
- * be used.  Anonymous indicates that no rhosts authentication will be used.
- * If login fails, this function prints an error and never returns.
- * This function does not require super-user privileges.
+ * check whether the supplied host key is valid, return only if ok.
  */
+
 void
-ssh_login(int host_key_valid,
-          RSA *own_host_key,
-          const char *orighost,
-          struct sockaddr_in *hostaddr,
-          uid_t original_real_uid)
+check_host_key(char *host,
+    struct sockaddr_in *hostaddr,
+    RSA *host_key)
 {
-        int i, type;
-        struct passwd *pw;
-        BIGNUM *key;
-        RSA *host_key, *file_key;
-        RSA *public_key;
-        int bits, rbits;
-        unsigned char session_key[SSH_SESSION_KEY_LENGTH];
-        const char *server_user, *local_user;
-        char *cp, *host, *ip = NULL;
+        RSA *file_key;
+        char *ip = NULL;
         char hostline[1000], *hostp;
-        unsigned char check_bytes[8];
-        unsigned int supported_ciphers, supported_authentications, protocol_flags;
         HostStatus host_status;
         HostStatus ip_status;
         int host_ip_differ = 0;
         int local = (ntohl(hostaddr->sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
-        int payload_len, clen, sum_len = 0;
-        u_int32_t rand = 0;
 
         /*
          * Turn off check_host_ip for proxy connects, since
@@ -1131,88 +1117,14 @@ ssh_login(int host_key_valid,
         if (options.check_host_ip)
                 ip = xstrdup(inet_ntoa(hostaddr->sin_addr));
 
-        /* Convert the user-supplied hostname into all lowercase. */
-        host = xstrdup(orighost);
-        for (cp = host; *cp; cp++)
-                if (isupper(*cp))
-                        *cp = tolower(*cp);
-
-        /* Exchange protocol version identification strings with the server. */
-        ssh_exchange_identification();
-
-        /* Put the connection into non-blocking mode. */
-        packet_set_nonblocking();
-
-        /* Get local user name.  Use it as server user if no user name was given. */
-        pw = getpwuid(original_real_uid);
-        if (!pw)
-                fatal("User id %d not found from user database.", original_real_uid);
-        local_user = xstrdup(pw->pw_name);
-        server_user = options.user ? options.user : local_user;
-
-        debug("Waiting for server public key.");
-
-        /* Wait for a public key packet from the server. */
-        packet_read_expect(&payload_len, SSH_SMSG_PUBLIC_KEY);
-
-        /* Get check bytes from the packet. */
-        for (i = 0; i < 8; i++)
-                check_bytes[i] = packet_get_char();
-
-        /* Get the public key. */
-        public_key = RSA_new();
-        bits = packet_get_int();/* bits */
-        public_key->e = BN_new();
-        packet_get_bignum(public_key->e, &clen);
-        sum_len += clen;
-        public_key->n = BN_new();
-        packet_get_bignum(public_key->n, &clen);
-        sum_len += clen;
-
-        rbits = BN_num_bits(public_key->n);
-        if (bits != rbits) {
-                log("Warning: Server lies about size of server public key: "
-                    "actual size is %d bits vs. announced %d.", rbits, bits);
-                log("Warning: This may be due to an old implementation of ssh.");
-        }
-        /* Get the host key. */
-        host_key = RSA_new();
-        bits = packet_get_int();/* bits */
-        host_key->e = BN_new();
-        packet_get_bignum(host_key->e, &clen);
-        sum_len += clen;
-        host_key->n = BN_new();
-        packet_get_bignum(host_key->n, &clen);
-        sum_len += clen;
-
-        rbits = BN_num_bits(host_key->n);
-        if (bits != rbits) {
-                log("Warning: Server lies about size of server host key: "
-                    "actual size is %d bits vs. announced %d.", rbits, bits);
-                log("Warning: This may be due to an old implementation of ssh.");
-        }
-        /* Store the host key from the known host file in here so that we
-           can compare it with the key for the IP address. */
+        /*
+         * Store the host key from the known host file in here so that we can
+         * compare it with the key for the IP address.
+         */
         file_key = RSA_new();
         file_key->n = BN_new();
         file_key->e = BN_new();
 
-        /* Get protocol flags. */
-        protocol_flags = packet_get_int();
-        packet_set_protocol_flags(protocol_flags);
-
-        supported_ciphers = packet_get_int();
-        supported_authentications = packet_get_int();
-
-        debug("Received server public key (%d bits) and host key (%d bits).",
-              BN_num_bits(public_key->n), BN_num_bits(host_key->n));
-
-        packet_integrity_check(payload_len,
-                               8 + 4 + sum_len + 0 + 4 + 0 + 0 + 4 + 4 + 4,
-                               SSH_SMSG_PUBLIC_KEY);
-
-        compute_session_id(session_id, check_bytes, host_key->n, public_key->n);
-
         /*
          * Check if the host key is present in the user\'s list of known
          * hosts or in the systemwide list.
@@ -1372,9 +1284,121 @@ ssh_login(int host_key_valid,
                  */
                 break;
         }
-
         if (options.check_host_ip)
                 xfree(ip);
+}
+
+/*
+ * Starts a dialog with the server, and authenticates the current user on the
+ * server.  This does not need any extra privileges.  The basic connection
+ * to the server must already have been established before this is called.
+ * User is the remote user; if it is NULL, the current local user name will
+ * be used.  Anonymous indicates that no rhosts authentication will be used.
+ * If login fails, this function prints an error and never returns.
+ * This function does not require super-user privileges.
+ */
+void
+ssh_login(int host_key_valid,
+          RSA *own_host_key,
+          const char *orighost,
+          struct sockaddr_in *hostaddr,
+          uid_t original_real_uid)
+{
+        int i, type;
+        struct passwd *pw;
+        BIGNUM *key;
+        RSA *host_key;
+        RSA *public_key;
+        int bits, rbits;
+        unsigned char session_key[SSH_SESSION_KEY_LENGTH];
+        const char *server_user, *local_user;
+        char *host, *cp;
+        unsigned char check_bytes[8];
+        unsigned int supported_ciphers, supported_authentications;
+        unsigned int server_flags, client_flags;
+        int payload_len, clen, sum_len = 0;
+        u_int32_t rand = 0;
+
+        /* Convert the user-supplied hostname into all lowercase. */
+        host = xstrdup(orighost);
+        for (cp = host; *cp; cp++)
+                if (isupper(*cp))
+                        *cp = tolower(*cp);
+
+        /* Exchange protocol version identification strings with the server. */
+        ssh_exchange_identification();
+
+        /* Put the connection into non-blocking mode. */
+        packet_set_nonblocking();
+
+        /* Get local user name.  Use it as server user if no user name was given. */
+        pw = getpwuid(original_real_uid);
+        if (!pw)
+                fatal("User id %d not found from user database.", original_real_uid);
+        local_user = xstrdup(pw->pw_name);
+        server_user = options.user ? options.user : local_user;
+
+        debug("Waiting for server public key.");
+
+        /* Wait for a public key packet from the server. */
+        packet_read_expect(&payload_len, SSH_SMSG_PUBLIC_KEY);
+
+        /* Get check bytes from the packet. */
+        for (i = 0; i < 8; i++)
+                check_bytes[i] = packet_get_char();
+
+        /* Get the public key. */
+        public_key = RSA_new();
+        bits = packet_get_int();/* bits */
+        public_key->e = BN_new();
+        packet_get_bignum(public_key->e, &clen);
+        sum_len += clen;
+        public_key->n = BN_new();
+        packet_get_bignum(public_key->n, &clen);
+        sum_len += clen;
+
+        rbits = BN_num_bits(public_key->n);
+        if (bits != rbits) {
+                log("Warning: Server lies about size of server public key: "
+                    "actual size is %d bits vs. announced %d.", rbits, bits);
+                log("Warning: This may be due to an old implementation of ssh.");
+        }
+        /* Get the host key. */
+        host_key = RSA_new();
+        bits = packet_get_int();/* bits */
+        host_key->e = BN_new();
+        packet_get_bignum(host_key->e, &clen);
+        sum_len += clen;
+        host_key->n = BN_new();
+        packet_get_bignum(host_key->n, &clen);
+        sum_len += clen;
+
+        rbits = BN_num_bits(host_key->n);
+        if (bits != rbits) {
+                log("Warning: Server lies about size of server host key: "
+                    "actual size is %d bits vs. announced %d.", rbits, bits);
+                log("Warning: This may be due to an old implementation of ssh.");
+        }
+
+        /* Get protocol flags. */
+        server_flags = packet_get_int();
+        packet_set_protocol_flags(server_flags);
+
+        supported_ciphers = packet_get_int();
+        supported_authentications = packet_get_int();
+
+        debug("Received server public key (%d bits) and host key (%d bits).",
+              BN_num_bits(public_key->n), BN_num_bits(host_key->n));
+
+        packet_integrity_check(payload_len,
+                               8 + 4 + sum_len + 0 + 4 + 0 + 0 + 4 + 4 + 4,
+                               SSH_SMSG_PUBLIC_KEY);
+
+        check_host_key(host, hostaddr, host_key);
+
+        client_flags = SSH_PROTOFLAG_SCREEN_NUMBER | SSH_PROTOFLAG_HOST_IN_FWD_OPEN;
+
+        compute_session_id(session_id, check_bytes, host_key->n, public_key->n);
 
         /* Generate a session key. */
         arc4random_stir();
@@ -1465,7 +1489,7 @@ ssh_login(int host_key_valid,
         packet_put_bignum(key);
 
         /* Send protocol flags. */
-        packet_put_int(SSH_PROTOFLAG_SCREEN_NUMBER | SSH_PROTOFLAG_HOST_IN_FWD_OPEN);
+        packet_put_int(client_flags);
 
         /* Send the packet now. */
         packet_send();