]> asedeno.scripts.mit.edu Git - PuTTY.git/blobdiff - cmdgen.c
first pass
[PuTTY.git] / cmdgen.c
index c15c01dd34bab2e82bd6529b78387344bbd93980..9d9d011ab7727fafeba728dbe05aafd64b795be4 100644 (file)
--- a/cmdgen.c
+++ b/cmdgen.c
@@ -10,6 +10,8 @@
 #include <limits.h>
 #include <assert.h>
 #include <time.h>
+#include <errno.h>
+#include <string.h>
 
 #include "putty.h"
 #include "ssh.h"
@@ -17,7 +19,7 @@
 #ifdef TEST_CMDGEN
 /*
  * This section overrides some definitions below for test purposes.
- * When compiled with -DTEST_CMDGEN:
+ * When compiled with -DTEST_CMDGEN (as cgtest.c will do):
  * 
  *  - Calls to get_random_data() are replaced with the diagnostic
  *    function below (I #define the name so that I can still link
@@ -35,7 +37,7 @@
  *    run tests.
  */
 #define get_random_data get_random_data_diagnostic
-char *get_random_data(int len)
+char *get_random_data(int len, const char *device)
 {
     char *buf = snewn(len, char);
     memset(buf, 'x', len);
@@ -50,8 +52,7 @@ int console_get_userpass_input(prompts_t *p, unsigned char *in, int inlen)
     int ret = 1;
     for (i = 0; i < p->n_prompts; i++) {
        if (promptsgot < nprompts) {
-           assert(strlen(prompts[promptsgot]) < p->prompts[i]->result_len);
-           strcpy(p->prompts[i]->result, prompts[promptsgot++]);
+           p->prompts[i]->result = dupstr(prompts[promptsgot++]);
        } else {
            promptsgot++;           /* track number of requests anyway */
            ret = 0;
@@ -91,7 +92,7 @@ static void no_progress(void *param, int action, int phase, int iprogress)
 {
 }
 
-void modalfatalbox(char *p, ...)
+void modalfatalbox(const char *p, ...)
 {
     va_list ap;
     fprintf(stderr, "FATAL ERROR: ");
@@ -102,7 +103,7 @@ void modalfatalbox(char *p, ...)
     cleanup_exit(1);
 }
 
-void nonfatal(char *p, ...)
+void nonfatal(const char *p, ...)
 {
     va_list ap;
     fprintf(stderr, "ERROR: ");
@@ -128,12 +129,14 @@ void sk_cleanup(void)
 
 void showversion(void)
 {
-    printf("puttygen: %s\n", ver);
+    char *buildinfo_text = buildinfo("\n");
+    printf("puttygen: %s\n%s\n", ver, buildinfo_text);
+    sfree(buildinfo_text);
 }
 
 void usage(int standalone)
 {
-    fprintf(stderr,
+    fprintf(standalone ? stderr : stdout,
            "Usage: puttygen ( keyfile | -t type [ -b bits ] )\n"
            "                [ -C comment ] [ -P ] [ -q ]\n"
            "                [ -o output-keyfile ] [ -O type | -l | -L"
@@ -149,76 +152,35 @@ void help(void)
      * Help message is an extended version of the usage message. So
      * start with that, plus a version heading.
      */
-    showversion();
+    printf("PuTTYgen: key generator and converter for the PuTTY tools\n"
+          "%s\n", ver);
     usage(FALSE);
-    fprintf(stderr,
-           "  -t    specify key type when generating (rsa, dsa, rsa1)\n"
-           "  -b    specify number of bits when generating key\n"
-           "  -C    change or specify key comment\n"
-           "  -P    change key passphrase\n"
-           "  -q    quiet: do not display progress bar\n"
-           "  -O    specify output type:\n"
-           "           private             output PuTTY private key format\n"
-           "           private-openssh     export OpenSSH private key\n"
-           "           private-sshcom      export ssh.com private key\n"
-           "           public              standard / ssh.com public key\n"
-           "           public-openssh      OpenSSH public key\n"
-           "           fingerprint         output the key fingerprint\n"
-           "  -o    specify output file\n"
-           "  -l    equivalent to `-O fingerprint'\n"
-           "  -L    equivalent to `-O public-openssh'\n"
-           "  -p    equivalent to `-O public'\n"
-           );
-}
-
-static int save_ssh2_pubkey(char *filename, char *comment,
-                           void *v_pub_blob, int pub_len)
-{
-    unsigned char *pub_blob = (unsigned char *)v_pub_blob;
-    char *p;
-    int i, column;
-    FILE *fp;
-
-    if (filename) {
-       fp = fopen(filename, "wb");
-       if (!fp)
-           return 0;
-    } else
-       fp = stdout;
-
-    fprintf(fp, "---- BEGIN SSH2 PUBLIC KEY ----\n");
-
-    if (comment) {
-       fprintf(fp, "Comment: \"");
-       for (p = comment; *p; p++) {
-           if (*p == '\\' || *p == '\"')
-               fputc('\\', fp);
-           fputc(*p, fp);
-       }
-       fprintf(fp, "\"\n");
-    }
-
-    i = 0;
-    column = 0;
-    while (i < pub_len) {
-       char buf[5];
-       int n = (pub_len - i < 3 ? pub_len - i : 3);
-       base64_encode_atom(pub_blob + i, n, buf);
-       i += n;
-       buf[4] = '\0';
-       fputs(buf, fp);
-       if (++column >= 16) {
-           fputc('\n', fp);
-           column = 0;
-       }
-    }
-    if (column > 0)
-       fputc('\n', fp);
-    
-    fprintf(fp, "---- END SSH2 PUBLIC KEY ----\n");
-    if (filename)
-       fclose(fp);
-    return 1;
+    printf("  -t    specify key type when generating (ed25519, ecdsa, rsa, "
+                                                       "dsa, rsa1)\n"
+          "  -b    specify number of bits when generating key\n"
+          "  -C    change or specify key comment\n"
+          "  -P    change key passphrase\n"
+          "  -q    quiet: do not display progress bar\n"
+          "  -O    specify output type:\n"
+          "           private             output PuTTY private key format\n"
+          "           private-openssh     export OpenSSH private key\n"
+          "           private-openssh-new export OpenSSH private key "
+                                             "(force new format)\n"
+          "           private-sshcom      export ssh.com private key\n"
+          "           public              RFC 4716 / ssh.com public key\n"
+          "           public-openssh      OpenSSH public key\n"
+          "           fingerprint         output the key fingerprint\n"
+          "  -o    specify output file\n"
+          "  -l    equivalent to `-O fingerprint'\n"
+          "  -L    equivalent to `-O public-openssh'\n"
+          "  -p    equivalent to `-O public'\n"
+          "  --old-passphrase file\n"
+          "        specify file containing old key passphrase\n"
+          "  --new-passphrase file\n"
+          "        specify file containing new key passphrase\n"
+          "  --random-device device\n"
+          "        specify device to read entropy from (e.g. /dev/urandom)\n"
+          );
 }
 
 static int move(char *from, char *to)
@@ -240,35 +202,43 @@ static int move(char *from, char *to)
     return TRUE;
 }
 
-static char *blobfp(char *alg, int bits, unsigned char *blob, int bloblen)
+static char *readpassphrase(const char *filename)
 {
-    char buffer[128];
-    unsigned char digest[16];
-    struct MD5Context md5c;
-    int i;
+    FILE *fp;
+    char *line;
 
-    MD5Init(&md5c);
-    MD5Update(&md5c, blob, bloblen);
-    MD5Final(digest, &md5c);
+    fp = fopen(filename, "r");
+    if (!fp) {
+       fprintf(stderr, "puttygen: cannot open %s: %s\n",
+               filename, strerror(errno));
+       return NULL;
+    }
+    line = fgetline(fp);
+    if (line)
+       line[strcspn(line, "\r\n")] = '\0';
+    else if (ferror(fp))
+       fprintf(stderr, "puttygen: error reading from %s: %s\n",
+               filename, strerror(errno));
+    else       /* empty file */
+       line = dupstr("");
+    fclose(fp);
+    return line;
+}
 
-    sprintf(buffer, "%s ", alg);
-    if (bits > 0)
-       sprintf(buffer + strlen(buffer), "%d ", bits);
-    for (i = 0; i < 16; i++)
-       sprintf(buffer + strlen(buffer), "%s%02x", i ? ":" : "",
-               digest[i]);
+#define DEFAULT_RSADSA_BITS 2048
 
-    return dupstr(buffer);
-}
+/* For Unix in particular, but harmless if this main() is reused elsewhere */
+const int buildinfo_gtk_relevant = FALSE;
 
 int main(int argc, char **argv)
 {
     char *infile = NULL;
     Filename *infilename = NULL, *outfilename = NULL;
-    enum { NOKEYGEN, RSA1, RSA2, DSA } keytype = NOKEYGEN;    
+    enum { NOKEYGEN, RSA1, RSA2, DSA, ECDSA, ED25519 } keytype = NOKEYGEN;
     char *outfile = NULL, *outfiletmp = NULL;
-    enum { PRIVATE, PUBLIC, PUBLICO, FP, OPENSSH, SSHCOM } outtype = PRIVATE;
-    int bits = 2048;
+    enum { PRIVATE, PUBLIC, PUBLICO, FP, OPENSSH_AUTO,
+           OPENSSH_NEW, SSHCOM } outtype = PRIVATE;
+    int bits = -1;
     char *comment = NULL, *origcomment = NULL;
     int change_passphrase = FALSE;
     int errs = FALSE, nogo = FALSE;
@@ -280,9 +250,10 @@ int main(int argc, char **argv)
     char *ssh2alg = NULL;
     const struct ssh_signkey *ssh2algf = NULL;
     int ssh2bloblen;
-    char *passphrase = NULL;
+    char *old_passphrase = NULL, *new_passphrase = NULL;
     int load_encrypted;
     progfn_t progressfn = is_interactive() ? progress_update : no_progress;
+    const char *random_device = NULL;
 
     /* ------------------------------------------------------------------
      * Parse the command line to figure out what we've been asked to do.
@@ -352,21 +323,41 @@ int main(int argc, char **argv)
                                 pgp_fingerprints();
                                 nogo = TRUE;
                             }
-                        }
-                       /*
-                        * For long options requiring an argument, add
-                        * code along the lines of
-                        * 
-                        * else if (!strcmp(opt, "-output")) {
-                        *     if (!val) {
-                        *         errs = TRUE;
-                         *         fprintf(stderr, "puttygen: option `-%s'"
-                         *                 " expects an argument\n", opt);
-                        *     } else
-                        *         ofile = val;
-                        * }
-                        */
-                       else {
+                       } else if (!strcmp(opt, "-old-passphrase")) {
+                           if (!val && argc > 1)
+                               --argc, val = *++argv;
+                           if (!val) {
+                               errs = TRUE;
+                               fprintf(stderr, "puttygen: option `-%s'"
+                                       " expects an argument\n", opt);
+                           } else {
+                               old_passphrase = readpassphrase(val);
+                               if (!old_passphrase)
+                                   errs = TRUE;
+                           }
+                       } else if (!strcmp(opt, "-new-passphrase")) {
+                           if (!val && argc > 1)
+                               --argc, val = *++argv;
+                           if (!val) {
+                               errs = TRUE;
+                               fprintf(stderr, "puttygen: option `-%s'"
+                                       " expects an argument\n", opt);
+                           } else {
+                               new_passphrase = readpassphrase(val);
+                               if (!new_passphrase)
+                                   errs = TRUE;
+                           }
+                       } else if (!strcmp(opt, "-random-device")) {
+                           if (!val && argc > 1)
+                               --argc, val = *++argv;
+                           if (!val) {
+                               errs = TRUE;
+                               fprintf(stderr, "puttygen: option `-%s'"
+                                       " expects an argument\n", opt);
+                           } else {
+                                random_device = val;
+                           }
+                       } else {
                            errs = TRUE;
                            fprintf(stderr,
                                    "puttygen: no such option `-%s'\n", opt);
@@ -437,6 +428,10 @@ int main(int argc, char **argv)
                            keytype = RSA1, sshver = 1;
                        else if (!strcmp(p, "dsa") || !strcmp(p, "dss"))
                            keytype = DSA, sshver = 2;
+                        else if (!strcmp(p, "ecdsa"))
+                            keytype = ECDSA, sshver = 2;
+                        else if (!strcmp(p, "ed25519"))
+                            keytype = ED25519, sshver = 2;
                        else {
                            fprintf(stderr,
                                    "puttygen: unknown key type `%s'\n", p);
@@ -459,7 +454,9 @@ int main(int argc, char **argv)
                        else if (!strcmp(p, "fingerprint"))
                            outtype = FP;
                        else if (!strcmp(p, "private-openssh"))
-                           outtype = OPENSSH, sshver = 2;
+                           outtype = OPENSSH_AUTO, sshver = 2;
+                       else if (!strcmp(p, "private-openssh-new"))
+                           outtype = OPENSSH_NEW, sshver = 2;
                        else if (!strcmp(p, "private-sshcom"))
                            outtype = SSHCOM, sshver = 2;
                        else {
@@ -497,6 +494,47 @@ int main(int argc, char **argv)
        }
     }
 
+    if (bits == -1) {
+        /*
+         * No explicit key size was specified. Default varies
+         * depending on key type.
+         */
+        switch (keytype) {
+          case ECDSA:
+            bits = 384;
+            break;
+          case ED25519:
+            bits = 256;
+            break;
+          default:
+            bits = DEFAULT_RSADSA_BITS;
+            break;
+        }
+    }
+
+    if (keytype == ECDSA && (bits != 256 && bits != 384 && bits != 521)) {
+        fprintf(stderr, "puttygen: invalid bits for ECDSA, choose 256, 384 or 521\n");
+        errs = TRUE;
+    }
+
+    if (keytype == ED25519 && (bits != 256)) {
+        fprintf(stderr, "puttygen: invalid bits for ED25519, choose 256\n");
+        errs = TRUE;
+    }
+
+    if (keytype == RSA2 || keytype == RSA1 || keytype == DSA) {
+        if (bits < 256) {
+            fprintf(stderr, "puttygen: cannot generate %s keys shorter than"
+                    " 256 bits\n", (keytype == DSA ? "DSA" : "RSA"));
+            errs = TRUE;
+        } else if (bits < DEFAULT_RSADSA_BITS) {
+            fprintf(stderr, "puttygen: warning: %s keys shorter than"
+                    " %d bits are probably not secure\n",
+                    (keytype == DSA ? "DSA" : "RSA"), DEFAULT_RSADSA_BITS);
+            /* but this is just a warning, so proceed anyway */
+        }
+    }
+
     if (errs)
        return 1;
 
@@ -529,7 +567,8 @@ int main(int argc, char **argv)
      * We must save the private part when generating a new key.
      */
     if (keytype != NOKEYGEN &&
-       (outtype != PRIVATE && outtype != OPENSSH && outtype != SSHCOM)) {
+       (outtype != PRIVATE && outtype != OPENSSH_AUTO &&
+         outtype != OPENSSH_NEW && outtype != SSHCOM)) {
        fprintf(stderr, "puttygen: this would generate a new key but "
                "discard the private part\n");
        return 1;
@@ -545,28 +584,6 @@ int main(int argc, char **argv)
        intype = key_type(infilename);
 
        switch (intype) {
-           /*
-            * It would be nice here to be able to load _public_
-            * key files, in any of a number of forms, and (a)
-            * convert them to other public key types, (b) print
-            * out their fingerprints. Or, I suppose, for real
-            * orthogonality, (c) change their comment!
-            * 
-            * In fact this opens some interesting possibilities.
-            * Suppose ssh2_userkey_loadpub() were able to load
-            * public key files as well as extracting the public
-            * key from private ones. And suppose I did the thing
-            * I've been wanting to do, where specifying a
-            * particular private key file for authentication
-            * causes any _other_ key in the agent to be discarded.
-            * Then, if you had an agent forwarded to the machine
-            * you were running Unix PuTTY or Plink on, and you
-            * needed to specify which of the keys in the agent it
-            * should use, you could do that by supplying a
-            * _public_ key file, thus not needing to trust even
-            * your encrypted private key file to the network. Ooh!
-            */
-
          case SSH_KEYTYPE_UNOPENABLE:
          case SSH_KEYTYPE_UNKNOWN:
            fprintf(stderr, "puttygen: unable to load file `%s': %s\n",
@@ -574,6 +591,7 @@ int main(int argc, char **argv)
            return 1;
 
          case SSH_KEYTYPE_SSH1:
+          case SSH_KEYTYPE_SSH1_PUBLIC:
            if (sshver == 2) {
                fprintf(stderr, "puttygen: conversion from SSH-1 to SSH-2 keys"
                        " not supported\n");
@@ -583,7 +601,10 @@ int main(int argc, char **argv)
            break;
 
          case SSH_KEYTYPE_SSH2:
-         case SSH_KEYTYPE_OPENSSH:
+          case SSH_KEYTYPE_SSH2_PUBLIC_RFC4716:
+          case SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH:
+         case SSH_KEYTYPE_OPENSSH_PEM:
+         case SSH_KEYTYPE_OPENSSH_NEW:
          case SSH_KEYTYPE_SSHCOM:
            if (sshver == 1) {
                fprintf(stderr, "puttygen: conversion from SSH-2 to SSH-1 keys"
@@ -592,6 +613,10 @@ int main(int argc, char **argv)
            }
            sshver = 2;
            break;
+
+         case SSH_KEYTYPE_OPENSSH_AUTO:
+          default:
+            assert(0 && "Should never see these types on an input file");
        }
     }
 
@@ -607,7 +632,8 @@ int main(int argc, char **argv)
      */
     if ((intype == SSH_KEYTYPE_SSH1 && outtype == PRIVATE) ||
        (intype == SSH_KEYTYPE_SSH2 && outtype == PRIVATE) ||
-       (intype == SSH_KEYTYPE_OPENSSH && outtype == OPENSSH) ||
+       (intype == SSH_KEYTYPE_OPENSSH_PEM && outtype == OPENSSH_AUTO) ||
+       (intype == SSH_KEYTYPE_OPENSSH_NEW && outtype == OPENSSH_NEW) ||
        (intype == SSH_KEYTYPE_SSHCOM && outtype == SSHCOM)) {
        if (!outfile) {
            outfile = infile;
@@ -625,7 +651,8 @@ int main(int argc, char **argv)
             * Bomb out rather than automatically choosing to write
             * a private key file to stdout.
             */
-           if (outtype==PRIVATE || outtype==OPENSSH || outtype==SSHCOM) {
+           if (outtype == PRIVATE || outtype == OPENSSH_AUTO ||
+                outtype == OPENSSH_NEW || outtype == SSHCOM) {
                fprintf(stderr, "puttygen: need to specify an output file\n");
                return 1;
            }
@@ -638,12 +665,23 @@ int main(int argc, char **argv)
      * out a private key format, or (b) the entire input key file
      * is encrypted.
      */
-    if (outtype == PRIVATE || outtype == OPENSSH || outtype == SSHCOM ||
-       intype == SSH_KEYTYPE_OPENSSH || intype == SSH_KEYTYPE_SSHCOM)
+    if (outtype == PRIVATE || outtype == OPENSSH_AUTO ||
+        outtype == OPENSSH_NEW || outtype == SSHCOM ||
+       intype == SSH_KEYTYPE_OPENSSH_PEM ||
+       intype == SSH_KEYTYPE_OPENSSH_NEW ||
+        intype == SSH_KEYTYPE_SSHCOM)
        load_encrypted = TRUE;
     else
        load_encrypted = FALSE;
 
+    if (load_encrypted && (intype == SSH_KEYTYPE_SSH1_PUBLIC ||
+                           intype == SSH_KEYTYPE_SSH2_PUBLIC_RFC4716 ||
+                           intype == SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH)) {
+        fprintf(stderr, "puttygen: cannot perform this action on a "
+                "public-key-only input file\n");
+        return 1;
+    }
+
     /* ------------------------------------------------------------------
      * Now we're ready to actually do some stuff.
      */
@@ -663,11 +701,15 @@ int main(int argc, char **argv)
        tm = ltime();
        if (keytype == DSA)
            strftime(default_comment, 30, "dsa-key-%Y%m%d", &tm);
+        else if (keytype == ECDSA)
+            strftime(default_comment, 30, "ecdsa-key-%Y%m%d", &tm);
+        else if (keytype == ED25519)
+            strftime(default_comment, 30, "ed25519-key-%Y%m%d", &tm);
        else
            strftime(default_comment, 30, "rsa-key-%Y%m%d", &tm);
 
        random_ref();
-       entropy = get_random_data(bits / 8);
+       entropy = get_random_data(bits / 8, random_device);
        if (!entropy) {
            fprintf(stderr, "puttygen: failed to collect entropy, "
                    "could not generate key\n");
@@ -684,6 +726,20 @@ int main(int argc, char **argv)
            ssh2key->data = dsskey;
            ssh2key->alg = &ssh_dss;
            ssh1key = NULL;
+        } else if (keytype == ECDSA) {
+            struct ec_key *ec = snew(struct ec_key);
+            ec_generate(ec, bits, progressfn, &prog);
+            ssh2key = snew(struct ssh2_userkey);
+            ssh2key->data = ec;
+            ssh2key->alg = ec->signalg;
+            ssh1key = NULL;
+        } else if (keytype == ED25519) {
+            struct ec_key *ec = snew(struct ec_key);
+            ec_edgenerate(ec, bits, progressfn, &prog);
+            ssh2key = snew(struct ssh2_userkey);
+            ssh2key->data = ec;
+            ssh2key->alg = &ssh_ecdsa_ed25519;
+            ssh1key = NULL;
        } else {
            struct RSAKey *rsakey = snew(struct RSAKey);
            rsa_generate(rsakey, bits, progressfn, &prog);
@@ -723,29 +779,32 @@ int main(int argc, char **argv)
         * If so, ask for a passphrase.
         */
        if (encrypted && load_encrypted) {
-           prompts_t *p = new_prompts(NULL);
-           int ret;
-           p->to_server = FALSE;
-           p->name = dupstr("SSH key passphrase");
-           add_prompt(p, dupstr("Enter passphrase to load key: "), FALSE);
-           ret = console_get_userpass_input(p, NULL, 0);
-           assert(ret >= 0);
-           if (!ret) {
-               free_prompts(p);
-               perror("puttygen: unable to read passphrase");
-               return 1;
-           } else {
-               passphrase = dupstr(p->prompts[0]->result);
-               free_prompts(p);
+           if (!old_passphrase) {
+               prompts_t *p = new_prompts(NULL);
+               int ret;
+               p->to_server = FALSE;
+               p->name = dupstr("SSH key passphrase");
+               add_prompt(p, dupstr("Enter passphrase to load key: "), FALSE);
+               ret = console_get_userpass_input(p, NULL, 0);
+               assert(ret >= 0);
+               if (!ret) {
+                   free_prompts(p);
+                   perror("puttygen: unable to read passphrase");
+                   return 1;
+               } else {
+                   old_passphrase = dupstr(p->prompts[0]->result);
+                   free_prompts(p);
+               }
            }
        } else {
-           passphrase = NULL;
+           old_passphrase = NULL;
        }
 
        switch (intype) {
            int ret;
 
          case SSH_KEYTYPE_SSH1:
+          case SSH_KEYTYPE_SSH1_PUBLIC:
            ssh1key = snew(struct RSAKey);
            if (!load_encrypted) {
                void *vblob;
@@ -777,7 +836,7 @@ int main(int argc, char **argv)
                ssh1key->q = NULL;
                ssh1key->iqmp = NULL;
            } else {
-               ret = loadrsakey(infilename, ssh1key, passphrase, &error);
+               ret = loadrsakey(infilename, ssh1key, old_passphrase, &error);
            }
            if (ret > 0)
                error = NULL;
@@ -786,18 +845,24 @@ int main(int argc, char **argv)
            break;
 
          case SSH_KEYTYPE_SSH2:
+          case SSH_KEYTYPE_SSH2_PUBLIC_RFC4716:
+          case SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH:
            if (!load_encrypted) {
                ssh2blob = ssh2_userkey_loadpub(infilename, &ssh2alg,
-                                               &ssh2bloblen, NULL, &error);
+                                               &ssh2bloblen, &origcomment,
+                                                &error);
                 if (ssh2blob) {
                     ssh2algf = find_pubkey_alg(ssh2alg);
                     if (ssh2algf)
-                        bits = ssh2algf->pubkey_bits(ssh2blob, ssh2bloblen);
+                        bits = ssh2algf->pubkey_bits(ssh2algf,
+                                                     ssh2blob, ssh2bloblen);
                     else
                         bits = -1;
                 }
+                sfree(ssh2alg);
            } else {
-               ssh2key = ssh2_load_userkey(infilename, passphrase, &error);
+               ssh2key = ssh2_load_userkey(infilename, old_passphrase,
+                                           &error);
            }
            if ((ssh2key && ssh2key != SSH2_WRONG_PASSPHRASE) || ssh2blob)
                error = NULL;
@@ -809,9 +874,10 @@ int main(int argc, char **argv)
            }
            break;
 
-         case SSH_KEYTYPE_OPENSSH:
+         case SSH_KEYTYPE_OPENSSH_PEM:
+         case SSH_KEYTYPE_OPENSSH_NEW:
          case SSH_KEYTYPE_SSHCOM:
-           ssh2key = import_ssh2(infilename, intype, passphrase, &error);
+           ssh2key = import_ssh2(infilename, intype, old_passphrase, &error);
            if (ssh2key) {
                if (ssh2key != SSH2_WRONG_PASSPHRASE)
                    error = NULL;
@@ -847,11 +913,18 @@ int main(int argc, char **argv)
        }
     }
 
+    /*
+     * Unless we're changing the passphrase, the old one (if any) is a
+     * reasonable default.
+     */
+    if (!change_passphrase && old_passphrase && !new_passphrase)
+       new_passphrase = dupstr(old_passphrase);
+
     /*
      * Prompt for a new passphrase if we have been asked to, or if
      * we have just generated a key.
      */
-    if (change_passphrase || keytype != NOKEYGEN) {
+    if (!new_passphrase && (change_passphrase || keytype != NOKEYGEN)) {
        prompts_t *p = new_prompts(NULL);
        int ret;
 
@@ -871,18 +944,14 @@ int main(int argc, char **argv)
                fprintf(stderr, "puttygen: passphrases do not match\n");
                return 1;
            }
-           if (passphrase) {
-               smemclr(passphrase, strlen(passphrase));
-               sfree(passphrase);
-           }
-           passphrase = dupstr(p->prompts[0]->result);
+           new_passphrase = dupstr(p->prompts[0]->result);
            free_prompts(p);
-           if (!*passphrase) {
-               sfree(passphrase);
-               passphrase = NULL;
-           }
        }
     }
+    if (new_passphrase && !*new_passphrase) {
+       sfree(new_passphrase);
+       new_passphrase = NULL;
+    }
 
     /*
      * Write output.
@@ -898,19 +967,19 @@ int main(int argc, char **argv)
        outfilename = filename_from_str(outfile ? outfile : "");
 
     switch (outtype) {
-       int ret;
+       int ret, real_outtype;
 
       case PRIVATE:
        if (sshver == 1) {
            assert(ssh1key);
-           ret = saversakey(outfilename, ssh1key, passphrase);
+           ret = saversakey(outfilename, ssh1key, new_passphrase);
            if (!ret) {
                fprintf(stderr, "puttygen: unable to save SSH-1 private key\n");
                return 1;
            }
        } else {
            assert(ssh2key);
-           ret = ssh2_save_userkey(outfilename, ssh2key, passphrase);
+           ret = ssh2_save_userkey(outfilename, ssh2key, new_passphrase);
            if (!ret) {
                fprintf(stderr, "puttygen: unable to save SSH-2 private key\n");
                return 1;
@@ -924,80 +993,33 @@ int main(int argc, char **argv)
 
       case PUBLIC:
       case PUBLICO:
-       if (sshver == 1) {
-           FILE *fp;
-           char *dec1, *dec2;
-
-           assert(ssh1key);
-
-           if (outfile)
-               fp = f_open(outfilename, "w", FALSE);
-           else
-               fp = stdout;
-           dec1 = bignum_decimal(ssh1key->exponent);
-           dec2 = bignum_decimal(ssh1key->modulus);
-           fprintf(fp, "%d %s %s %s\n", bignum_bitcount(ssh1key->modulus),
-                   dec1, dec2, ssh1key->comment);
-           sfree(dec1);
-           sfree(dec2);
-           if (outfile)
-               fclose(fp);
-       } else if (outtype == PUBLIC) {
-           if (!ssh2blob) {
-               assert(ssh2key);
-               ssh2blob = ssh2key->alg->public_blob(ssh2key->data,
-                                                    &ssh2bloblen);
-           }
-           save_ssh2_pubkey(outfile, ssh2key ? ssh2key->comment : origcomment,
-                            ssh2blob, ssh2bloblen);
-       } else if (outtype == PUBLICO) {
-           char *buffer, *p;
-           int i;
-           FILE *fp;
+        {
+            FILE *fp;
+
+            if (outfile)
+                fp = f_open(outfilename, "w", FALSE);
+            else
+                fp = stdout;
+
+            if (sshver == 1) {
+                ssh1_write_pubkey(fp, ssh1key);
+            } else {
+                if (!ssh2blob) {
+                    assert(ssh2key);
+                    ssh2blob = ssh2key->alg->public_blob(ssh2key->data,
+                                                         &ssh2bloblen);
+                }
 
-           if (!ssh2blob) {
-               assert(ssh2key);
-               ssh2blob = ssh2key->alg->public_blob(ssh2key->data,
-                                                    &ssh2bloblen);
-           }
-           if (!ssh2alg) {
-               assert(ssh2key);
-               ssh2alg = ssh2key->alg->name;
-           }
-           if (ssh2key)
-               comment = ssh2key->comment;
-           else
-               comment = origcomment;
-
-           buffer = snewn(strlen(ssh2alg) +
-                          4 * ((ssh2bloblen+2) / 3) +
-                          strlen(comment) + 3, char);
-           strcpy(buffer, ssh2alg);
-           p = buffer + strlen(buffer);
-           *p++ = ' ';
-           i = 0;
-           while (i < ssh2bloblen) {
-               int n = (ssh2bloblen - i < 3 ? ssh2bloblen - i : 3);
-               base64_encode_atom(ssh2blob + i, n, p);
-               i += n;
-               p += 4;
-           }
-           if (*comment) {
-               *p++ = ' ';
-               strcpy(p, comment);
-           } else
-               *p++ = '\0';
+                ssh2_write_pubkey(fp, ssh2key ? ssh2key->comment : origcomment,
+                                  ssh2blob, ssh2bloblen,
+                                  (outtype == PUBLIC ?
+                                   SSH_KEYTYPE_SSH2_PUBLIC_RFC4716 :
+                                   SSH_KEYTYPE_SSH2_PUBLIC_OPENSSH));
+            }
 
-           if (outfile)
-               fp = f_open(outfilename, "w", FALSE);
-           else
-               fp = stdout;
-           fprintf(fp, "%s\n", buffer);
            if (outfile)
                fclose(fp);
-
-           sfree(buffer);
-       }
+        }
        break;
 
       case FP:
@@ -1011,10 +1033,11 @@ int main(int argc, char **argv)
                rsa_fingerprint(fingerprint, 128, ssh1key);
            } else {
                if (ssh2key) {
-                   fingerprint = ssh2key->alg->fingerprint(ssh2key->data);
+                   fingerprint = ssh2_fingerprint(ssh2key->alg,
+                                                   ssh2key->data);
                } else {
                    assert(ssh2blob);
-                   fingerprint = blobfp(ssh2alg, bits, ssh2blob, ssh2bloblen);
+                   fingerprint = ssh2_fingerprint_blob(ssh2blob, ssh2bloblen);
                }
            }
 
@@ -1030,13 +1053,27 @@ int main(int argc, char **argv)
        }
        break;
        
-      case OPENSSH:
+      case OPENSSH_AUTO:
+      case OPENSSH_NEW:
       case SSHCOM:
        assert(sshver == 2);
        assert(ssh2key);
        random_ref(); /* both foreign key types require randomness,
                        * for IV or padding */
-       ret = export_ssh2(outfilename, outtype, ssh2key, passphrase);
+        switch (outtype) {
+          case OPENSSH_AUTO:
+            real_outtype = SSH_KEYTYPE_OPENSSH_AUTO;
+            break;
+          case OPENSSH_NEW:
+            real_outtype = SSH_KEYTYPE_OPENSSH_NEW;
+            break;
+          case SSHCOM:
+            real_outtype = SSH_KEYTYPE_SSHCOM;
+            break;
+          default:
+            assert(0 && "control flow goof");
+        }
+       ret = export_ssh2(outfilename, real_outtype, ssh2key, new_passphrase);
        if (!ret) {
            fprintf(stderr, "puttygen: unable to export key\n");
            return 1;
@@ -1048,9 +1085,13 @@ int main(int argc, char **argv)
        break;
     }
 
-    if (passphrase) {
-       smemclr(passphrase, strlen(passphrase));
-       sfree(passphrase);
+    if (old_passphrase) {
+       smemclr(old_passphrase, strlen(old_passphrase));
+       sfree(old_passphrase);
+    }
+    if (new_passphrase) {
+       smemclr(new_passphrase, strlen(new_passphrase));
+       sfree(new_passphrase);
     }
 
     if (ssh1key)
@@ -1124,6 +1165,8 @@ void test(int retval, ...)
     } else {
        passes++;
     }
+
+    sfree(argv);
 }
 
 void filecmp(char *file1, char *file2, char *fmt, ...)
@@ -1171,7 +1214,7 @@ char *cleanup_fp(char *s)
     s += strspn(s, " \n\t");
     s += strcspn(s, " \n\t");
 
-    return dupprintf("%.*s", s - p, p);
+    return dupprintf("%.*s", (int)(s - p), p);
 }
 
 char *get_fp(char *filename)