PuTTY can now detect when one of the Pageant keys it tries matches

the private key file given in the config; if it spots this then it
avoids trying it again (and in particular avoids needing to ask for
the passphrase when it knows perfectly well it won't work).

git-svn-id: svn://svn.tartarus.org/sgt/putty@1523 cda61777-01e9-0310-a592-d414129be87e

diff --git a/ssh.c b/ssh.c
index e0fed88..6ff530f 100644 (file)
--- a/ssh.c
+++ b/ssh.c
@@ -1859,6 +1859,8 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
     static unsigned char session_id[16];
     static int cipher_type;
     static char username[100];
+    static void *publickey_blob;
+    int publickey_bloblen;
 
     crBegin;
 
@@ -2105,6 +2107,12 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
 
     tried_publickey = 0;
     tis_auth_refused = ccard_auth_refused = 0;
+    /* Load the public half of cfg.keyfile so we notice if it's in Pageant */
+    if (*cfg.keyfile) {
+       if (!rsakey_pubblob(cfg.keyfile, &publickey_blob, &publickey_bloblen))
+           publickey_blob = NULL;
+    } else
+       publickey_blob = NULL;
 
     while (pktin.type == SSH1_SMSG_FAILURE) {
        static char password[100];
@@ -2152,6 +2160,11 @@ static int do_ssh1_login(unsigned char *in, int inlen, int ispkt)
                        sprintf(buf, "Trying Pageant key #%d", i);
                        logevent(buf);
                    }
+                   if (publickey_blob &&
+                       !memcmp(p, publickey_blob, publickey_bloblen)) {
+                       logevent("This key matches configured key file");
+                       tried_publickey = 1;
+                   }
                    p += 4;
                    p += ssh1_read_bignum(p, &key.exponent);
                    p += ssh1_read_bignum(p, &key.modulus);
@@ -3751,6 +3764,8 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
     static char username[100];
     static char pwprompt[200];
     static char password[100];
+    static void *publickey_blob;
+    static int publickey_bloblen;
 
     crBegin;
 
@@ -3891,6 +3906,12 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
        tried_agent = FALSE;
        tried_keyb_inter = FALSE;
        kbd_inter_running = FALSE;
+       /* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
+       if (*cfg.keyfile) {
+           publickey_blob = ssh2_userkey_loadpub(cfg.keyfile, NULL,
+                                                 &publickey_bloblen);
+       } else
+           publickey_blob = NULL;
 
        while (1) {
            /*
@@ -4046,6 +4067,12 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
                        }
                        pklen = GET_32BIT(p);
                        p += 4;
+                       if (publickey_blob &&
+                           pklen == publickey_bloblen &&
+                           !memcmp(p, publickey_blob, publickey_bloblen)) {
+                           logevent("This key matches configured key file");
+                           tried_pubkey_config = 1;
+                       }
                        pkblob = p;
                        p += pklen;
                        alglen = GET_32BIT(pkblob);