| Message ID | 20190830171611.32540-1-ddiss@suse.de (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | target: compare full CHAP_A Algorithm strings | expand |
On Fri, 30 Aug 2019 19:16:11 +0200, David Disseldorp wrote: ... > LIO currently checks for this value by only comparing a single byte in > the tokenized Algorithm string, which means that any value starting with > a '5' (e.g. "55") is interpreted as "CHAP with MD5". FWIW, this can be triggered via a simple libiscsi hack: https://github.com/ddiss/libiscsi/commit/a6a41fd002c18edaad5d7df320373ec0232b460d.patch Cheers, David
On 8/30/19 10:16 AM, David Disseldorp wrote: > RFC 2307 states: > > For CHAP [RFC1994], in the first step, the initiator MUST send: > > CHAP_A=<A1,A2...> > > Where A1,A2... are proposed algorithms, in order of preference. > ... > For the Algorithm, as stated in [RFC1994], one value is required to > be implemented: > > 5 (CHAP with MD5) > > LIO currently checks for this value by only comparing a single byte in > the tokenized Algorithm string, which means that any value starting with > a '5' (e.g. "55") is interpreted as "CHAP with MD5". Fix this by > comparing the entire tokenized string. > > Signed-off-by: David Disseldorp <ddiss@suse.de> > --- > drivers/target/iscsi/iscsi_target_auth.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c > index 51ddca2033e0..8fe9b12a07a4 100644 > --- a/drivers/target/iscsi/iscsi_target_auth.c > +++ b/drivers/target/iscsi/iscsi_target_auth.c > @@ -70,7 +70,7 @@ static int chap_check_algorithm(const char *a_str) > if (!token) > goto out; > > - if (!strncmp(token, "5", 1)) { > + if (!strcmp(token, "5")) { > pr_debug("Selected MD5 Algorithm\n"); > kfree(orig); > return CHAP_DIGEST_MD5; > Reviewed-by: Lee Duncan <lduncan@suse.com>
diff --git a/drivers/target/iscsi/iscsi_target_auth.c b/drivers/target/iscsi/iscsi_target_auth.c index 51ddca2033e0..8fe9b12a07a4 100644 --- a/drivers/target/iscsi/iscsi_target_auth.c +++ b/drivers/target/iscsi/iscsi_target_auth.c @@ -70,7 +70,7 @@ static int chap_check_algorithm(const char *a_str) if (!token) goto out; - if (!strncmp(token, "5", 1)) { + if (!strcmp(token, "5")) { pr_debug("Selected MD5 Algorithm\n"); kfree(orig); return CHAP_DIGEST_MD5;
RFC 2307 states: For CHAP [RFC1994], in the first step, the initiator MUST send: CHAP_A=<A1,A2...> Where A1,A2... are proposed algorithms, in order of preference. ... For the Algorithm, as stated in [RFC1994], one value is required to be implemented: 5 (CHAP with MD5) LIO currently checks for this value by only comparing a single byte in the tokenized Algorithm string, which means that any value starting with a '5' (e.g. "55") is interpreted as "CHAP with MD5". Fix this by comparing the entire tokenized string. Signed-off-by: David Disseldorp <ddiss@suse.de> --- drivers/target/iscsi/iscsi_target_auth.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)