1305750 - Certutil produces malformed IP name constraints when creating certificates

Status: NEW

(NSS :: Tools, defect, P5)

Description

[Martin Ukrop]

User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36

Steps to reproduce:

Use case: Creating certificates containing IP name constraints using certutil.

1) Create auxiliary password and noise files, create new database
echo password >passwd
certutil -N -d . -f passwd
echo noisenoisenoisenoise >noise

2) Create a self-signed CA with name constraint of permitted subtree 97.97.97.97/32
echo -e "8\n\x61\x61\x61\x61\xff\xff\xff\xff\n1\nn\ny\n" >args
certutil -S -d . -n test1CA -x -t CT,C, -s "CN=Test1CA" -m 1 --extNC -f passwd -z noise <args
certutil -L -d . -n test1CA

3) Create end certificate signed by above CA with SAN IP:97.97.97.97
certutil -S -d . -n test1Server -c test1CA -t ,, -s "CN=Test1Server" -m 2 --extSAN ip:97.97.97.97 -f passwd -z noise <args
certutil -L -d . -n test1Server

4) Validate above created end certificate with IP SAN
certutil -V -d . -n test1Server -u C

5) Create another self-signed CA with name constraint of permitted subtree 97.97.97.97/16
echo -e "8\n\x61\x61\x61\x61\xff\xff\x00\x00\n1\nn\ny\n" >args
certutil -S -d . -n test2 -x -t ,, -s "CN=Test2" -m 3 --extNC -f passwd -z noise <args
certutil -L -d . -n test2


Actual results:

2) The certificate's name constraint extension has an IP range of 87:08:61:61:61:61:ff:ff:ff:ff.
Certutil prefixes with 2 bytes that are not supposed to be there (name type and length). Furthermore, name constraints IP extension with lenght not 8 (IPv4) nor 32 (IPv6) is invalid.

This is done since the name constraints names are handled the same way as subject alternative names, see nss/cmd/certutil/certext.c, function getGeneralName (lines 169-186).

4) The end certificate fails to validate (due to extra first 2 bytes in IP range). Same certificate created by GnuTLS validates OK in NSS.

5) The CA certificate IP constraint misses last 2 bytes (that were \x00) (and also has the extra prefix as described above).


Expected results:

2) The certificate's name constraints extension IP rangne should have been 61:61:61:61:ff:ff:ff:ff.

4) The end certificate should be considered valid (IP 97.97.97.97 in in permitted range of 97.97.97.97/32).

5) The certificate's name constraints extension IP rangne should have been 61:61:61:61:ff:ff:00:00.