From 6c86782f9e6cdaa4c31a92dd9b019dc9e0ffe8fd Mon Sep 17 00:00:00 2001 From: Simon Tatham Date: Sun, 1 Mar 2015 12:55:31 +0000 Subject: Add some missing smemclrs and sfrees. The absence of these could have prevented sensitive private key information from being properly cleared out of memory that PuTTY tools had finished with. Thanks to Patrick Coleman for spotting this and sending a patch. Origin: upstream, http://tartarus.org/~simon-git/gitweb/?p=putty.git;a=commitdiff;h=65f69bca7363ceceeac515ae2a82b8f8adc6404d Bug: http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/private-key-not-wiped-2.html Bug-Debian: http://bugs.debian.org/779488 Patch-Name: private-key-not-wiped-2.patch --- tools/plink/sshpubk.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/tools/plink/sshpubk.c b/tools/plink/sshpubk.c index cf9e44b36..2f8a2be30 100644 --- a/tools/plink/sshpubk.c +++ b/tools/plink/sshpubk.c @@ -796,6 +796,7 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, goto error; } sfree(public_blob); + smemclr(private_blob, private_blob_len); sfree(private_blob); sfree(encryption); if (errorstr) @@ -816,8 +817,10 @@ struct ssh2_userkey *ssh2_load_userkey(const Filename *filename, sfree(mac); if (public_blob) sfree(public_blob); - if (private_blob) - sfree(private_blob); + if (private_blob) { + smemclr(private_blob, private_blob_len); + sfree(private_blob); + } if (errorstr) *errorstr = error; return ret; @@ -1106,8 +1109,14 @@ int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key, } fp = f_open(filename, "w", TRUE); - if (!fp) - return 0; + if (!fp) { + sfree(pub_blob); + smemclr(priv_blob, priv_blob_len); + sfree(priv_blob); + smemclr(priv_blob_encrypted, priv_blob_len); + sfree(priv_blob_encrypted); + return 0; + } fprintf(fp, "PuTTY-User-Key-File-2: %s\n", key->alg->name); fprintf(fp, "Encryption: %s\n", cipherstr); fprintf(fp, "Comment: %s\n", key->comment); @@ -1124,6 +1133,7 @@ int ssh2_save_userkey(const Filename *filename, struct ssh2_userkey *key, sfree(pub_blob); smemclr(priv_blob, priv_blob_len); sfree(priv_blob); + smemclr(priv_blob_encrypted, priv_blob_len); sfree(priv_blob_encrypted); return 1; } -- cgit v1.2.3