diff --git a/include/linux/security.h b/include/linux/security.h index bc27254915608..1112a79a7dbad 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -127,6 +127,7 @@ enum lockdown_reason { LOCKDOWN_PERF, LOCKDOWN_TRACEFS, LOCKDOWN_XMON_RW, + LOCKDOWN_XFRM_SECRET, LOCKDOWN_CONFIDENTIALITY_MAX, }; diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index d0c32a8fcc4a9..0727ac853b550 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -848,21 +848,84 @@ static int copy_user_offload(struct xfrm_state_offload *xso, struct sk_buff *skb return 0; } +static bool xfrm_redact(void) +{ + return IS_ENABLED(CONFIG_SECURITY) && + security_locked_down(LOCKDOWN_XFRM_SECRET); +} + static int copy_to_user_auth(struct xfrm_algo_auth *auth, struct sk_buff *skb) { struct xfrm_algo *algo; + struct xfrm_algo_auth *ap; struct nlattr *nla; + bool redact_secret = xfrm_redact(); 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 && auth->alg_key_len) + 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(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; + bool redact_secret = xfrm_redact(); + + if (!nla) + return -EMSGSIZE; + + ap = nla_data(nla); + memcpy(ap, aead, sizeof(*aead)); + + if (redact_secret && aead->alg_key_len) + 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(struct xfrm_algo *ealg, struct sk_buff *skb) +{ + struct xfrm_algo *ap; + bool redact_secret = xfrm_redact(); + 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 && ealg->alg_key_len) + 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; } @@ -906,20 +969,17 @@ 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(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); 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(x->ealg, skb); if (ret) goto out; } diff --git a/security/security.c b/security/security.c index a28045dc9e7f6..abff77c1c8a78 100644 --- a/security/security.c +++ b/security/security.c @@ -65,6 +65,7 @@ const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = { [LOCKDOWN_PERF] = "unsafe use of perf", [LOCKDOWN_TRACEFS] = "use of tracefs", [LOCKDOWN_XMON_RW] = "xmon read and write access", + [LOCKDOWN_XFRM_SECRET] = "xfrm SA secret", [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality", };