| Message ID | 20200728154342.GA31835@moon.secunet.de |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | David Miller |
| Headers | show |
| Series | [ipsec-next] xfrm: add /proc/sys/core/net/xfrm_redact_secret | expand |
On Tue, Jul 28, 2020 at 05:47:30PM +0200, Antony Antony wrote: > when enabled, 1, redact XFRM SA secret in the netlink response to > xfrm_get_sa() or dump all sa. > > e.g > echo 1 > /proc/sys/net/core/xfrm_redact_secret > ip xfrm state > src 172.16.1.200 dst 172.16.1.100 > proto esp spi 0x00000002 reqid 2 mode tunnel > replay-window 0 > aead rfc4106(gcm(aes)) 0x0000000000000000000000000000000000000000 96 > > the aead secret is redacted. > > /proc/sys/core/net/xfrm_redact_secret is a toggle. > Once enabled, either at compile or via proc, it can not be disabled. > Redacting secret is a FIPS 140-2 requirement. Couldn't you use the existing fips_enabled sysctl? Cheers,
On Wed, Jul 29, 2020 at 02:22:52 +1000, Herbert Xu wrote: > On Tue, Jul 28, 2020 at 05:47:30PM +0200, Antony Antony wrote: > > when enabled, 1, redact XFRM SA secret in the netlink response to > > xfrm_get_sa() or dump all sa. > > > > e.g > > echo 1 > /proc/sys/net/core/xfrm_redact_secret > > ip xfrm state > > src 172.16.1.200 dst 172.16.1.100 > > proto esp spi 0x00000002 reqid 2 mode tunnel > > replay-window 0 > > aead rfc4106(gcm(aes)) 0x0000000000000000000000000000000000000000 96 > > > > the aead secret is redacted. > > > > /proc/sys/core/net/xfrm_redact_secret is a toggle. > > Once enabled, either at compile or via proc, it can not be disabled. > > Redacting secret is a FIPS 140-2 requirement. > > Couldn't you use the existing fips_enabled sysctl? that could be a step, however, not yet. Libreswan in FIPS mode with xfrm_redact_secret enabled would work fine, however, enabling xfrm_redact_secret would break Strongswan in FIPS mode. We can add this option fips_enabled once Strongswan does not need SA secret, child_sa->update(). Also there was interest to able to use xfrm_redact_secret independent of FIPS. I thik for now it best to be ouside fips_enabled.
Am Dienstag, 28. Juli 2020, 17:47:30 CEST schrieb Antony Antony: Hi Antony, > when enabled, 1, redact XFRM SA secret in the netlink response to > xfrm_get_sa() or dump all sa. > > e.g > echo 1 > /proc/sys/net/core/xfrm_redact_secret > ip xfrm state > src 172.16.1.200 dst 172.16.1.100 > proto esp spi 0x00000002 reqid 2 mode tunnel > replay-window 0 > aead rfc4106(gcm(aes)) 0x0000000000000000000000000000000000000000 96 > > the aead secret is redacted. > > /proc/sys/core/net/xfrm_redact_secret is a toggle. > Once enabled, either at compile or via proc, it can not be disabled. > Redacting secret is a FIPS 140-2 requirement. > > Cc: Stephan Mueller <smueller@chronox.de> > Signed-off-by: Antony Antony <antony.antony@secunet.com> > --- > Documentation/networking/xfrm_sysctl.rst | 7 +++ > include/net/netns/xfrm.h | 1 + > net/xfrm/Kconfig | 10 ++++ > net/xfrm/xfrm_sysctl.c | 20 +++++++ > net/xfrm/xfrm_user.c | 76 +++++++++++++++++++++--- > 5 files changed, 105 insertions(+), 9 deletions(-) > > diff --git a/Documentation/networking/xfrm_sysctl.rst > b/Documentation/networking/xfrm_sysctl.rst index 47b9bbdd0179..26432b0ff3ac > 100644 > --- a/Documentation/networking/xfrm_sysctl.rst > +++ b/Documentation/networking/xfrm_sysctl.rst > @@ -9,3 +9,10 @@ XFRM Syscall > > xfrm_acq_expires - INTEGER > default 30 - hard timeout in seconds for acquire requests > + > +xfrm_redact_secret - INTEGER > + A toggle to redact xfrm SA's secret to userspace. > + When true the kernel, netlink message will redact SA secret > + to userspace. This is part of FIPS 140-2 requirement. > + Once the value is set to true, either at compile or at run time, > + it can not be set to false. > diff --git a/include/net/netns/xfrm.h b/include/net/netns/xfrm.h > index 59f45b1e9dac..0ca9328daad4 100644 > --- a/include/net/netns/xfrm.h > +++ b/include/net/netns/xfrm.h > @@ -64,6 +64,7 @@ struct netns_xfrm { > u32 sysctl_aevent_rseqth; > int sysctl_larval_drop; > u32 sysctl_acq_expires; > + u32 sysctl_redact_secret; > #ifdef CONFIG_SYSCTL > struct ctl_table_header *sysctl_hdr; > #endif > diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig > index 5b9a5ab48111..270a4e906a15 100644 > --- a/net/xfrm/Kconfig > +++ b/net/xfrm/Kconfig > @@ -91,6 +91,16 @@ config XFRM_ESP > select CRYPTO_SEQIV > select CRYPTO_SHA256 > > +config XFRM_REDACT_SECRET > + bool "Redact xfrm SA secret in netlink message" > + depends on SYSCTL > + default n > + help > + Enable XFRM SA secret redact in the netlink message. > + Redacting secret is a FIPS 140-2 requirement. > + Once enabled at compile, the value can not be set to false on > + a running system. > + > config XFRM_IPCOMP > tristate > select XFRM_ALGO > diff --git a/net/xfrm/xfrm_sysctl.c b/net/xfrm/xfrm_sysctl.c > index 0c6c5ef65f9d..a41aa325a478 100644 > --- a/net/xfrm/xfrm_sysctl.c > +++ b/net/xfrm/xfrm_sysctl.c > @@ -4,15 +4,25 @@ > #include <net/net_namespace.h> > #include <net/xfrm.h> > > +#ifdef CONFIG_SYSCTL > +#ifdef CONFIG_XFRM_REDACT_SECRET > +#define XFRM_REDACT_SECRET 1 > +#else > +#define XFRM_REDACT_SECRET 0 > +#endif > +#endif > + > static void __net_init __xfrm_sysctl_init(struct net *net) > { > net->xfrm.sysctl_aevent_etime = XFRM_AE_ETIME; > net->xfrm.sysctl_aevent_rseqth = XFRM_AE_SEQT_SIZE; > net->xfrm.sysctl_larval_drop = 1; > net->xfrm.sysctl_acq_expires = 30; > + net->xfrm.sysctl_redact_secret = XFRM_REDACT_SECRET; > } > > #ifdef CONFIG_SYSCTL > + > static struct ctl_table xfrm_table[] = { > { > .procname = "xfrm_aevent_etime", > @@ -38,6 +48,15 @@ static struct ctl_table xfrm_table[] = { > .mode = 0644, > .proc_handler = proc_dointvec > }, > + { > + .procname = "xfrm_redact_secret", > + .maxlen = sizeof(u32), > + .mode = 0644, > + /* only handle a transition from "0" to "1" */ > + .proc_handler = proc_dointvec_minmax, > + .extra1 = SYSCTL_ONE, > + .extra2 = SYSCTL_ONE, > + }, > {} > }; > > @@ -54,6 +73,7 @@ int __net_init xfrm_sysctl_init(struct net *net) > table[1].data = &net->xfrm.sysctl_aevent_rseqth; > table[2].data = &net->xfrm.sysctl_larval_drop; > table[3].data = &net->xfrm.sysctl_acq_expires; > + table[4].data = &net->xfrm.sysctl_redact_secret; > > /* Don't export sysctls to unprivileged users */ > if (net->user_ns != &init_user_ns) > diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c > index e6cfaa680ef3..a3e89dddea9d 100644 > --- a/net/xfrm/xfrm_user.c > +++ b/net/xfrm/xfrm_user.c > @@ -848,21 +848,78 @@ static int copy_user_offload(struct xfrm_state_offload > *xso, struct sk_buff *skb return 0; > } > > -static int copy_to_user_auth(struct xfrm_algo_auth *auth, struct sk_buff > *skb) +static int copy_to_user_auth(u32 redact_secret, struct > xfrm_algo_auth *auth, + struct sk_buff *skb) > { > struct xfrm_algo *algo; > + struct xfrm_algo_auth *ap; > struct nlattr *nla; > > nla = nla_reserve(skb, XFRMA_ALG_AUTH, > sizeof(*algo) + (auth->alg_key_len + 7) / 8); > if (!nla) > return -EMSGSIZE; > - > algo = nla_data(nla); > strncpy(algo->alg_name, auth->alg_name, sizeof(algo->alg_name)); > - memcpy(algo->alg_key, auth->alg_key, (auth->alg_key_len + 7) / 8); > + > + if (redact_secret && auth->alg_key_len) > + memset(algo->alg_key, 0, (auth->alg_key_len + 7) / 8); > + else > + memcpy(algo->alg_key, auth->alg_key, > + (auth->alg_key_len + 7) / 8); > algo->alg_key_len = auth->alg_key_len; > > + nla = nla_reserve(skb, XFRMA_ALG_AUTH_TRUNC, xfrm_alg_auth_len(auth)); > + if (!nla) > + return -EMSGSIZE; > + ap = nla_data(nla); > + memcpy(ap, auth, sizeof(struct xfrm_algo_auth)); > + if (redact_secret) You test for auth->alg_key_len above. Shouldn't there such a check here too? > + memset(ap->alg_key, 0, (auth->alg_key_len + 7) / 8); > + else > + memcpy(ap->alg_key, auth->alg_key, > + (auth->alg_key_len + 7) / 8); > + return 0; > +} > + > +static int copy_to_user_aead(u32 redact_secret, > + struct xfrm_algo_aead *aead, struct sk_buff *skb) > +{ > + struct nlattr *nla = nla_reserve(skb, XFRMA_ALG_AEAD, aead_len(aead)); > + struct xfrm_algo_aead *ap; > + > + if (!nla) > + return -EMSGSIZE; > + > + ap = nla_data(nla); > + memcpy(ap, aead, sizeof(*aead)); > + > + if (redact_secret) And here? > + memset(ap->alg_key, 0, (aead->alg_key_len + 7) / 8); > + else > + memcpy(ap->alg_key, aead->alg_key, > + (aead->alg_key_len + 7) / 8); > + return 0; > +} > + > +static int copy_to_user_ealg(u32 redact_secret, struct xfrm_algo *ealg, > + struct sk_buff *skb) > +{ > + struct xfrm_algo *ap; > + struct nlattr *nla = nla_reserve(skb, XFRMA_ALG_CRYPT, > + xfrm_alg_len(ealg)); > + if (!nla) > + return -EMSGSIZE; > + > + ap = nla_data(nla); > + memcpy(ap, ealg, sizeof(*ealg)); > + > + if (redact_secret) Here, too? > + memset(ap->alg_key, 0, (ealg->alg_key_len + 7) / 8); > + else > + memcpy(ap->alg_key, ealg->alg_key, > + (ealg->alg_key_len + 7) / 8); > + > return 0; > } > > @@ -884,6 +941,7 @@ static int copy_to_user_state_extra(struct xfrm_state > *x, struct sk_buff *skb) > { > int ret = 0; > + struct net *net = xs_net(x); > > copy_to_user_state(x, p); > > @@ -906,20 +964,20 @@ static int copy_to_user_state_extra(struct xfrm_state > *x, goto out; > } > if (x->aead) { > - ret = nla_put(skb, XFRMA_ALG_AEAD, aead_len(x->aead), x- >aead); > + ret = copy_to_user_aead(net->xfrm.sysctl_redact_secret, > + x->aead, skb); > if (ret) > goto out; > } > if (x->aalg) { > - ret = copy_to_user_auth(x->aalg, skb); > - if (!ret) > - ret = nla_put(skb, XFRMA_ALG_AUTH_TRUNC, > - xfrm_alg_auth_len(x->aalg), x->aalg); > + ret = copy_to_user_auth(net->xfrm.sysctl_redact_secret, > + x->aalg, skb); > if (ret) > goto out; > } > if (x->ealg) { > - ret = nla_put(skb, XFRMA_ALG_CRYPT, xfrm_alg_len(x->ealg), x- >ealg); > + ret = copy_to_user_ealg(net->xfrm.sysctl_redact_secret, > + x->ealg, skb); > if (ret) > goto out; > } Ciao Stephan
On Tue, Jul 28, 2020 at 21:09:10 +0200, Stephan Mueller wrote: > Am Dienstag, 28. Juli 2020, 17:47:30 CEST schrieb Antony Antony: > > Hi Antony, > > > when enabled, 1, redact XFRM SA secret in the netlink response to > > xfrm_get_sa() or dump all sa. > > > > e.g > > echo 1 > /proc/sys/net/core/xfrm_redact_secret > > ip xfrm state > > src 172.16.1.200 dst 172.16.1.100 > > proto esp spi 0x00000002 reqid 2 mode tunnel > > replay-window 0 > > aead rfc4106(gcm(aes)) 0x0000000000000000000000000000000000000000 96 > > > > the aead secret is redacted. > > > > /proc/sys/core/net/xfrm_redact_secret is a toggle. > > Once enabled, either at compile or via proc, it can not be disabled. > > Redacting secret is a FIPS 140-2 requirement. > > > > Cc: Stephan Mueller <smueller@chronox.de> > > Signed-off-by: Antony Antony <antony.antony@secunet.com> > > --- > > Documentation/networking/xfrm_sysctl.rst | 7 +++ > > include/net/netns/xfrm.h | 1 + > > net/xfrm/Kconfig | 10 ++++ > > net/xfrm/xfrm_sysctl.c | 20 +++++++ > > net/xfrm/xfrm_user.c | 76 +++++++++++++++++++++--- > > 5 files changed, 105 insertions(+), 9 deletions(-) > > > > diff --git a/Documentation/networking/xfrm_sysctl.rst > > b/Documentation/networking/xfrm_sysctl.rst index 47b9bbdd0179..26432b0ff3ac > > 100644 > > --- a/Documentation/networking/xfrm_sysctl.rst > > +++ b/Documentation/networking/xfrm_sysctl.rst > > @@ -9,3 +9,10 @@ XFRM Syscall > > > > xfrm_acq_expires - INTEGER > > default 30 - hard timeout in seconds for acquire requests > > + > > +xfrm_redact_secret - INTEGER > > + A toggle to redact xfrm SA's secret to userspace. > > + When true the kernel, netlink message will redact SA secret > > + to userspace. This is part of FIPS 140-2 requirement. > > + Once the value is set to true, either at compile or at run time, > > + it can not be set to false. > > diff --git a/include/net/netns/xfrm.h b/include/net/netns/xfrm.h > > index 59f45b1e9dac..0ca9328daad4 100644 > > --- a/include/net/netns/xfrm.h > > +++ b/include/net/netns/xfrm.h > > @@ -64,6 +64,7 @@ struct netns_xfrm { > > u32 sysctl_aevent_rseqth; > > int sysctl_larval_drop; > > u32 sysctl_acq_expires; > > + u32 sysctl_redact_secret; > > #ifdef CONFIG_SYSCTL > > struct ctl_table_header *sysctl_hdr; > > #endif > > diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig > > index 5b9a5ab48111..270a4e906a15 100644 > > --- a/net/xfrm/Kconfig > > +++ b/net/xfrm/Kconfig > > @@ -91,6 +91,16 @@ config XFRM_ESP > > select CRYPTO_SEQIV > > select CRYPTO_SHA256 > > > > +config XFRM_REDACT_SECRET > > + bool "Redact xfrm SA secret in netlink message" > > + depends on SYSCTL > > + default n > > + help > > + Enable XFRM SA secret redact in the netlink message. > > + Redacting secret is a FIPS 140-2 requirement. > > + Once enabled at compile, the value can not be set to false on > > + a running system. > > + > > config XFRM_IPCOMP > > tristate > > select XFRM_ALGO > > diff --git a/net/xfrm/xfrm_sysctl.c b/net/xfrm/xfrm_sysctl.c > > index 0c6c5ef65f9d..a41aa325a478 100644 > > --- a/net/xfrm/xfrm_sysctl.c > > +++ b/net/xfrm/xfrm_sysctl.c > > @@ -4,15 +4,25 @@ > > #include <net/net_namespace.h> > > #include <net/xfrm.h> > > > > +#ifdef CONFIG_SYSCTL > > +#ifdef CONFIG_XFRM_REDACT_SECRET > > +#define XFRM_REDACT_SECRET 1 > > +#else > > +#define XFRM_REDACT_SECRET 0 > > +#endif > > +#endif > > + > > static void __net_init __xfrm_sysctl_init(struct net *net) > > { > > net->xfrm.sysctl_aevent_etime = XFRM_AE_ETIME; > > net->xfrm.sysctl_aevent_rseqth = XFRM_AE_SEQT_SIZE; > > net->xfrm.sysctl_larval_drop = 1; > > net->xfrm.sysctl_acq_expires = 30; > > + net->xfrm.sysctl_redact_secret = XFRM_REDACT_SECRET; > > } > > > > #ifdef CONFIG_SYSCTL > > + > > static struct ctl_table xfrm_table[] = { > > { > > .procname = "xfrm_aevent_etime", > > @@ -38,6 +48,15 @@ static struct ctl_table xfrm_table[] = { > > .mode = 0644, > > .proc_handler = proc_dointvec > > }, > > + { > > + .procname = "xfrm_redact_secret", > > + .maxlen = sizeof(u32), > > + .mode = 0644, > > + /* only handle a transition from "0" to "1" */ > > + .proc_handler = proc_dointvec_minmax, > > + .extra1 = SYSCTL_ONE, > > + .extra2 = SYSCTL_ONE, > > + }, > > {} > > }; > > > > @@ -54,6 +73,7 @@ int __net_init xfrm_sysctl_init(struct net *net) > > table[1].data = &net->xfrm.sysctl_aevent_rseqth; > > table[2].data = &net->xfrm.sysctl_larval_drop; > > table[3].data = &net->xfrm.sysctl_acq_expires; > > + table[4].data = &net->xfrm.sysctl_redact_secret; > > > > /* Don't export sysctls to unprivileged users */ > > if (net->user_ns != &init_user_ns) > > diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c > > index e6cfaa680ef3..a3e89dddea9d 100644 > > --- a/net/xfrm/xfrm_user.c > > +++ b/net/xfrm/xfrm_user.c > > @@ -848,21 +848,78 @@ static int copy_user_offload(struct xfrm_state_offload > > *xso, struct sk_buff *skb return 0; > > } > > > > -static int copy_to_user_auth(struct xfrm_algo_auth *auth, struct sk_buff > > *skb) +static int copy_to_user_auth(u32 redact_secret, struct > > xfrm_algo_auth *auth, + struct sk_buff *skb) > > { > > struct xfrm_algo *algo; > > + struct xfrm_algo_auth *ap; > > struct nlattr *nla; > > > > nla = nla_reserve(skb, XFRMA_ALG_AUTH, > > sizeof(*algo) + (auth->alg_key_len + 7) / 8); > > if (!nla) > > return -EMSGSIZE; > > - > > algo = nla_data(nla); > > strncpy(algo->alg_name, auth->alg_name, sizeof(algo->alg_name)); > > - memcpy(algo->alg_key, auth->alg_key, (auth->alg_key_len + 7) / 8); > > + > > + if (redact_secret && auth->alg_key_len) > > + memset(algo->alg_key, 0, (auth->alg_key_len + 7) / 8); > > + else > > + memcpy(algo->alg_key, auth->alg_key, > > + (auth->alg_key_len + 7) / 8); > > algo->alg_key_len = auth->alg_key_len; > > > > + nla = nla_reserve(skb, XFRMA_ALG_AUTH_TRUNC, xfrm_alg_auth_len(auth)); > > + if (!nla) > > + return -EMSGSIZE; > > + ap = nla_data(nla); > > + memcpy(ap, auth, sizeof(struct xfrm_algo_auth)); > > + if (redact_secret) > > You test for auth->alg_key_len above. Shouldn't there such a check here too? It is a good idea add checks before all memset calls. I will send a new version out soon. thanks, -antony
diff --git a/Documentation/networking/xfrm_sysctl.rst b/Documentation/networking/xfrm_sysctl.rst index 47b9bbdd0179..26432b0ff3ac 100644 --- a/Documentation/networking/xfrm_sysctl.rst +++ b/Documentation/networking/xfrm_sysctl.rst @@ -9,3 +9,10 @@ XFRM Syscall xfrm_acq_expires - INTEGER default 30 - hard timeout in seconds for acquire requests + +xfrm_redact_secret - INTEGER + A toggle to redact xfrm SA's secret to userspace. + When true the kernel, netlink message will redact SA secret + to userspace. This is part of FIPS 140-2 requirement. + Once the value is set to true, either at compile or at run time, + it can not be set to false. diff --git a/include/net/netns/xfrm.h b/include/net/netns/xfrm.h index 59f45b1e9dac..0ca9328daad4 100644 --- a/include/net/netns/xfrm.h +++ b/include/net/netns/xfrm.h @@ -64,6 +64,7 @@ struct netns_xfrm { u32 sysctl_aevent_rseqth; int sysctl_larval_drop; u32 sysctl_acq_expires; + u32 sysctl_redact_secret; #ifdef CONFIG_SYSCTL struct ctl_table_header *sysctl_hdr; #endif diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig index 5b9a5ab48111..270a4e906a15 100644 --- a/net/xfrm/Kconfig +++ b/net/xfrm/Kconfig @@ -91,6 +91,16 @@ config XFRM_ESP select CRYPTO_SEQIV select CRYPTO_SHA256 +config XFRM_REDACT_SECRET + bool "Redact xfrm SA secret in netlink message" + depends on SYSCTL + default n + help + Enable XFRM SA secret redact in the netlink message. + Redacting secret is a FIPS 140-2 requirement. + Once enabled at compile, the value can not be set to false on + a running system. + config XFRM_IPCOMP tristate select XFRM_ALGO diff --git a/net/xfrm/xfrm_sysctl.c b/net/xfrm/xfrm_sysctl.c index 0c6c5ef65f9d..a41aa325a478 100644 --- a/net/xfrm/xfrm_sysctl.c +++ b/net/xfrm/xfrm_sysctl.c @@ -4,15 +4,25 @@ #include <net/net_namespace.h> #include <net/xfrm.h> +#ifdef CONFIG_SYSCTL +#ifdef CONFIG_XFRM_REDACT_SECRET +#define XFRM_REDACT_SECRET 1 +#else +#define XFRM_REDACT_SECRET 0 +#endif +#endif + static void __net_init __xfrm_sysctl_init(struct net *net) { net->xfrm.sysctl_aevent_etime = XFRM_AE_ETIME; net->xfrm.sysctl_aevent_rseqth = XFRM_AE_SEQT_SIZE; net->xfrm.sysctl_larval_drop = 1; net->xfrm.sysctl_acq_expires = 30; + net->xfrm.sysctl_redact_secret = XFRM_REDACT_SECRET; } #ifdef CONFIG_SYSCTL + static struct ctl_table xfrm_table[] = { { .procname = "xfrm_aevent_etime", @@ -38,6 +48,15 @@ static struct ctl_table xfrm_table[] = { .mode = 0644, .proc_handler = proc_dointvec }, + { + .procname = "xfrm_redact_secret", + .maxlen = sizeof(u32), + .mode = 0644, + /* only handle a transition from "0" to "1" */ + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ONE, + .extra2 = SYSCTL_ONE, + }, {} }; @@ -54,6 +73,7 @@ int __net_init xfrm_sysctl_init(struct net *net) table[1].data = &net->xfrm.sysctl_aevent_rseqth; table[2].data = &net->xfrm.sysctl_larval_drop; table[3].data = &net->xfrm.sysctl_acq_expires; + table[4].data = &net->xfrm.sysctl_redact_secret; /* Don't export sysctls to unprivileged users */ if (net->user_ns != &init_user_ns) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index e6cfaa680ef3..a3e89dddea9d 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -848,21 +848,78 @@ static int copy_user_offload(struct xfrm_state_offload *xso, struct sk_buff *skb return 0; } -static int copy_to_user_auth(struct xfrm_algo_auth *auth, struct sk_buff *skb) +static int copy_to_user_auth(u32 redact_secret, struct xfrm_algo_auth *auth, + struct sk_buff *skb) { struct xfrm_algo *algo; + struct xfrm_algo_auth *ap; struct nlattr *nla; nla = nla_reserve(skb, XFRMA_ALG_AUTH, sizeof(*algo) + (auth->alg_key_len + 7) / 8); if (!nla) return -EMSGSIZE; - algo = nla_data(nla); strncpy(algo->alg_name, auth->alg_name, sizeof(algo->alg_name)); - memcpy(algo->alg_key, auth->alg_key, (auth->alg_key_len + 7) / 8); + + if (redact_secret && auth->alg_key_len) + memset(algo->alg_key, 0, (auth->alg_key_len + 7) / 8); + else + memcpy(algo->alg_key, auth->alg_key, + (auth->alg_key_len + 7) / 8); algo->alg_key_len = auth->alg_key_len; + nla = nla_reserve(skb, XFRMA_ALG_AUTH_TRUNC, xfrm_alg_auth_len(auth)); + if (!nla) + return -EMSGSIZE; + ap = nla_data(nla); + memcpy(ap, auth, sizeof(struct xfrm_algo_auth)); + if (redact_secret) + memset(ap->alg_key, 0, (auth->alg_key_len + 7) / 8); + else + memcpy(ap->alg_key, auth->alg_key, + (auth->alg_key_len + 7) / 8); + return 0; +} + +static int copy_to_user_aead(u32 redact_secret, + struct xfrm_algo_aead *aead, struct sk_buff *skb) +{ + struct nlattr *nla = nla_reserve(skb, XFRMA_ALG_AEAD, aead_len(aead)); + struct xfrm_algo_aead *ap; + + if (!nla) + return -EMSGSIZE; + + ap = nla_data(nla); + memcpy(ap, aead, sizeof(*aead)); + + if (redact_secret) + memset(ap->alg_key, 0, (aead->alg_key_len + 7) / 8); + else + memcpy(ap->alg_key, aead->alg_key, + (aead->alg_key_len + 7) / 8); + return 0; +} + +static int copy_to_user_ealg(u32 redact_secret, struct xfrm_algo *ealg, + struct sk_buff *skb) +{ + struct xfrm_algo *ap; + struct nlattr *nla = nla_reserve(skb, XFRMA_ALG_CRYPT, + xfrm_alg_len(ealg)); + if (!nla) + return -EMSGSIZE; + + ap = nla_data(nla); + memcpy(ap, ealg, sizeof(*ealg)); + + if (redact_secret) + memset(ap->alg_key, 0, (ealg->alg_key_len + 7) / 8); + else + memcpy(ap->alg_key, ealg->alg_key, + (ealg->alg_key_len + 7) / 8); + return 0; } @@ -884,6 +941,7 @@ static int copy_to_user_state_extra(struct xfrm_state *x, struct sk_buff *skb) { int ret = 0; + struct net *net = xs_net(x); copy_to_user_state(x, p); @@ -906,20 +964,20 @@ static int copy_to_user_state_extra(struct xfrm_state *x, goto out; } if (x->aead) { - ret = nla_put(skb, XFRMA_ALG_AEAD, aead_len(x->aead), x->aead); + ret = copy_to_user_aead(net->xfrm.sysctl_redact_secret, + x->aead, skb); if (ret) goto out; } if (x->aalg) { - ret = copy_to_user_auth(x->aalg, skb); - if (!ret) - ret = nla_put(skb, XFRMA_ALG_AUTH_TRUNC, - xfrm_alg_auth_len(x->aalg), x->aalg); + ret = copy_to_user_auth(net->xfrm.sysctl_redact_secret, + x->aalg, skb); if (ret) goto out; } if (x->ealg) { - ret = nla_put(skb, XFRMA_ALG_CRYPT, xfrm_alg_len(x->ealg), x->ealg); + ret = copy_to_user_ealg(net->xfrm.sysctl_redact_secret, + x->ealg, skb); if (ret) goto out; }
when enabled, 1, redact XFRM SA secret in the netlink response to xfrm_get_sa() or dump all sa. e.g echo 1 > /proc/sys/net/core/xfrm_redact_secret ip xfrm state src 172.16.1.200 dst 172.16.1.100 proto esp spi 0x00000002 reqid 2 mode tunnel replay-window 0 aead rfc4106(gcm(aes)) 0x0000000000000000000000000000000000000000 96 the aead secret is redacted. /proc/sys/core/net/xfrm_redact_secret is a toggle. Once enabled, either at compile or via proc, it can not be disabled. Redacting secret is a FIPS 140-2 requirement. Cc: Stephan Mueller <smueller@chronox.de> Signed-off-by: Antony Antony <antony.antony@secunet.com> --- Documentation/networking/xfrm_sysctl.rst | 7 +++ include/net/netns/xfrm.h | 1 + net/xfrm/Kconfig | 10 ++++ net/xfrm/xfrm_sysctl.c | 20 +++++++ net/xfrm/xfrm_user.c | 76 +++++++++++++++++++++--- 5 files changed, 105 insertions(+), 9 deletions(-)