Big revision to CHECKLST.txt for release.pl and Mason.

[PuTTY.git] / import.c

diff --git a/import.c b/import.c
index d009241b1541d92f2ae0392507042f3669416d13..4f3ed1fab00308ece7a40c467c4a8010d05e300b 100644 (file)
--- a/import.c
+++ b/import.c
@@ -176,14 +176,16 @@ static int ber_read_id_len(void *source, int sourcelen,
        return -1;
 
     if (*p & 0x80) {
+        unsigned len;
        int n = *p & 0x7F;
        p++, sourcelen--;
        if (sourcelen < n)
            return -1;
-       *length = 0;
+       len = 0;
        while (n--)
-           *length = (*length << 8) | (*p++);
+           len = (len << 8) | (*p++);
        sourcelen -= n;
+        *length = toint(len);
     } else {
        *length = *p;
        p++, sourcelen--;
@@ -345,8 +347,8 @@ static struct openssh_key *load_openssh_key(const Filename *filename,
        goto error;
     }
     strip_crlf(line);
-    if (0 != strncmp(line, "-----BEGIN ", 11) ||
-       0 != strcmp(line+strlen(line)-16, "PRIVATE KEY-----")) {
+    if (!strstartswith(line, "-----BEGIN ") ||
+        !strendswith(line, "PRIVATE KEY-----")) {
        errmsg = "file does not begin with OpenSSH key header";
        goto error;
     }
@@ -369,9 +371,12 @@ static struct openssh_key *load_openssh_key(const Filename *filename,
            goto error;
        }
        strip_crlf(line);
-       if (0 == strncmp(line, "-----END ", 9) &&
-           0 == strcmp(line+strlen(line)-16, "PRIVATE KEY-----"))
+       if (strstartswith(line, "-----END ") &&
+           strendswith(line, "PRIVATE KEY-----")) {
+            sfree(line);
+            line = NULL;
            break;                     /* done */
+        }
        if ((p = strchr(line, ':')) != NULL) {
            if (headers_done) {
                errmsg = "header found in body of key data";
@@ -596,7 +601,8 @@ struct ssh2_userkey *openssh_read(const Filename *filename, char *passphrase,
      * decrypt, if the key was encrypted. */
     ret = ber_read_id_len(p, key->keyblob_len, &id, &len, &flags);
     p += ret;
-    if (ret < 0 || id != 16) {
+    if (ret < 0 || id != 16 || len < 0 ||
+        key->keyblob+key->keyblob_len-p < len) {
        errmsg = "ASN.1 decoding failure";
         retval = key->encrypted ? SSH2_WRONG_PASSPHRASE : NULL;
        goto error;
@@ -627,7 +633,7 @@ struct ssh2_userkey *openssh_read(const Filename *filename, char *passphrase,
        ret = ber_read_id_len(p, key->keyblob+key->keyblob_len-p,
                              &id, &len, &flags);
        p += ret;
-       if (ret < 0 || id != 2 ||
+       if (ret < 0 || id != 2 || len < 0 ||
            key->keyblob+key->keyblob_len-p < len) {
            errmsg = "ASN.1 decoding failure";
            retval = key->encrypted ? SSH2_WRONG_PASSPHRASE : NULL;
@@ -1091,8 +1097,11 @@ static struct sshcom_key *load_sshcom_key(const Filename *filename,
            goto error;
        }
        strip_crlf(line);
-        if (!strcmp(line, "---- END SSH2 ENCRYPTED PRIVATE KEY ----"))
+        if (!strcmp(line, "---- END SSH2 ENCRYPTED PRIVATE KEY ----")) {
+            sfree(line);
+            line = NULL;
             break;                     /* done */
+        }
        if ((p = strchr(line, ':')) != NULL) {
            if (headers_done) {
                errmsg = "header found in body of key data";
@@ -1181,10 +1190,14 @@ static struct sshcom_key *load_sshcom_key(const Filename *filename,
        goto error;
     }
 
+    fclose(fp);
     if (errmsg_p) *errmsg_p = NULL;
     return ret;
 
     error:
+    if (fp)
+        fclose(fp);
+
     if (line) {
        smemclr(line, strlen(line));
        sfree(line);
@@ -1207,20 +1220,22 @@ int sshcom_encrypted(const Filename *filename, char **comment)
     struct sshcom_key *key = load_sshcom_key(filename, NULL);
     int pos, len, answer;
 
+    answer = 0;
+
     *comment = NULL;
     if (!key)
-        return 0;
+        goto done;
 
     /*
      * Check magic number.
      */
-    if (GET_32BIT(key->keyblob) != 0x3f6ff9eb)
-        return 0;                      /* key is invalid */
+    if (GET_32BIT(key->keyblob) != 0x3f6ff9eb) {
+        goto done;                     /* key is invalid */
+    }
 
     /*
      * Find the cipher-type string.
      */
-    answer = 0;
     pos = 8;
     if (key->keyblob_len < pos+4)
         goto done;                     /* key is far too short */
@@ -1235,11 +1250,15 @@ int sshcom_encrypted(const Filename *filename, char **comment)
         answer = 1;
 
     done:
-    *comment = dupstr(key->comment);
-    smemclr(key->keyblob, key->keyblob_size);
-    sfree(key->keyblob);
-    smemclr(key, sizeof(*key));
-    sfree(key);
+    if (key) {
+        *comment = dupstr(key->comment);
+        smemclr(key->keyblob, key->keyblob_size);
+        sfree(key->keyblob);
+        smemclr(key, sizeof(*key));
+        sfree(key);
+    } else {
+        *comment = dupstr("");
+    }
     return answer;
 }
 
@@ -1463,9 +1482,12 @@ struct ssh2_userkey *sshcom_read(const Filename *filename, char *passphrase,
         pos += put_mp(blob+pos, p.start, p.bytes);
         pos += put_mp(blob+pos, u.start, u.bytes);
         privlen = pos - publen;
-    } else if (type == DSA) {
+    } else {
         struct mpint_pos p, q, g, x, y;
         int pos = 4;
+
+        assert(type == DSA); /* the only other option from the if above */
+
         if (GET_32BIT(ciphertext) != 0) {
             errmsg = "predefined DSA parameters not supported";
             goto error;
@@ -1490,8 +1512,7 @@ struct ssh2_userkey *sshcom_read(const Filename *filename, char *passphrase,
         publen = pos;
         pos += put_mp(blob+pos, x.start, x.bytes);
         privlen = pos - publen;
-    } else
-       return NULL;
+    }
 
     assert(privlen > 0);              /* should have bombed by now if not */