diff options
Diffstat (limited to 'crypto/algif_rng.c')
| -rw-r--r-- | crypto/algif_rng.c | 177 |
1 files changed, 164 insertions, 13 deletions
diff --git a/crypto/algif_rng.c b/crypto/algif_rng.c index 22df3799a17b..407408c43730 100644 --- a/crypto/algif_rng.c +++ b/crypto/algif_rng.c @@ -38,6 +38,7 @@ * DAMAGE. */ +#include <linux/capability.h> #include <linux/module.h> #include <crypto/rng.h> #include <linux/random.h> @@ -53,15 +54,26 @@ struct rng_ctx { #define MAXSIZE 128 unsigned int len; struct crypto_rng *drng; + u8 *addtl; + size_t addtl_len; }; -static int rng_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, - int flags) +struct rng_parent_ctx { + struct crypto_rng *drng; + u8 *entropy; +}; + +static void rng_reset_addtl(struct rng_ctx *ctx) { - struct sock *sk = sock->sk; - struct alg_sock *ask = alg_sk(sk); - struct rng_ctx *ctx = ask->private; - int err = -EFAULT; + kfree_sensitive(ctx->addtl); + ctx->addtl = NULL; + ctx->addtl_len = 0; +} + +static int _rng_recvmsg(struct crypto_rng *drng, struct msghdr *msg, size_t len, + u8 *addtl, size_t addtl_len) +{ + int err = 0; int genlen = 0; u8 result[MAXSIZE]; @@ -82,7 +94,7 @@ static int rng_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, * seeding as they automatically seed. The X9.31 DRNG will return * an error if it was not seeded properly. */ - genlen = crypto_rng_get_bytes(ctx->drng, result, len); + genlen = crypto_rng_generate(drng, addtl, addtl_len, result, len); if (genlen < 0) return genlen; @@ -92,6 +104,63 @@ static int rng_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, return err ? err : len; } +static int rng_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, + int flags) +{ + struct sock *sk = sock->sk; + struct alg_sock *ask = alg_sk(sk); + struct rng_ctx *ctx = ask->private; + + return _rng_recvmsg(ctx->drng, msg, len, NULL, 0); +} + +static int rng_test_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, + int flags) +{ + struct sock *sk = sock->sk; + struct alg_sock *ask = alg_sk(sk); + struct rng_ctx *ctx = ask->private; + int ret; + + lock_sock(sock->sk); + ret = _rng_recvmsg(ctx->drng, msg, len, ctx->addtl, ctx->addtl_len); + rng_reset_addtl(ctx); + release_sock(sock->sk); + + return ret; +} + +static int rng_test_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) +{ + int err; + struct alg_sock *ask = alg_sk(sock->sk); + struct rng_ctx *ctx = ask->private; + + lock_sock(sock->sk); + if (len > MAXSIZE) { + err = -EMSGSIZE; + goto unlock; + } + + rng_reset_addtl(ctx); + ctx->addtl = kmalloc(len, GFP_KERNEL); + if (!ctx->addtl) { + err = -ENOMEM; + goto unlock; + } + + err = memcpy_from_msg(ctx->addtl, msg, len); + if (err) { + rng_reset_addtl(ctx); + goto unlock; + } + ctx->addtl_len = len; + +unlock: + release_sock(sock->sk); + return err ? err : len; +} + static struct proto_ops algif_rng_ops = { .family = PF_ALG, @@ -101,11 +170,9 @@ static struct proto_ops algif_rng_ops = { .ioctl = sock_no_ioctl, .listen = sock_no_listen, .shutdown = sock_no_shutdown, - .getsockopt = sock_no_getsockopt, .mmap = sock_no_mmap, .bind = sock_no_bind, .accept = sock_no_accept, - .setsockopt = sock_no_setsockopt, .sendmsg = sock_no_sendmsg, .sendpage = sock_no_sendpage, @@ -113,14 +180,53 @@ static struct proto_ops algif_rng_ops = { .recvmsg = rng_recvmsg, }; +static struct proto_ops __maybe_unused algif_rng_test_ops = { + .family = PF_ALG, + + .connect = sock_no_connect, + .socketpair = sock_no_socketpair, + .getname = sock_no_getname, + .ioctl = sock_no_ioctl, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .mmap = sock_no_mmap, + .bind = sock_no_bind, + .accept = sock_no_accept, + .sendpage = sock_no_sendpage, + + .release = af_alg_release, + .recvmsg = rng_test_recvmsg, + .sendmsg = rng_test_sendmsg, +}; + static void *rng_bind(const char *name, u32 type, u32 mask) { - return crypto_alloc_rng(name, type, mask); + struct rng_parent_ctx *pctx; + struct crypto_rng *rng; + + pctx = kzalloc(sizeof(*pctx), GFP_KERNEL); + if (!pctx) + return ERR_PTR(-ENOMEM); + + rng = crypto_alloc_rng(name, type, mask); + if (IS_ERR(rng)) { + kfree(pctx); + return ERR_CAST(rng); + } + + pctx->drng = rng; + return pctx; } static void rng_release(void *private) { - crypto_free_rng(private); + struct rng_parent_ctx *pctx = private; + + if (unlikely(!pctx)) + return; + crypto_free_rng(pctx->drng); + kfree_sensitive(pctx->entropy); + kfree_sensitive(pctx); } static void rng_sock_destruct(struct sock *sk) @@ -128,6 +234,7 @@ static void rng_sock_destruct(struct sock *sk) struct alg_sock *ask = alg_sk(sk); struct rng_ctx *ctx = ask->private; + rng_reset_addtl(ctx); sock_kfree_s(sk, ctx, ctx->len); af_alg_release_parent(sk); } @@ -135,6 +242,7 @@ static void rng_sock_destruct(struct sock *sk) static int rng_accept_parent(void *private, struct sock *sk) { struct rng_ctx *ctx; + struct rng_parent_ctx *pctx = private; struct alg_sock *ask = alg_sk(sk); unsigned int len = sizeof(*ctx); @@ -143,6 +251,8 @@ static int rng_accept_parent(void *private, struct sock *sk) return -ENOMEM; ctx->len = len; + ctx->addtl = NULL; + ctx->addtl_len = 0; /* * No seeding done at that point -- if multiple accepts are @@ -150,20 +260,58 @@ static int rng_accept_parent(void *private, struct sock *sk) * state of the RNG. */ - ctx->drng = private; + ctx->drng = pctx->drng; ask->private = ctx; sk->sk_destruct = rng_sock_destruct; + /* + * Non NULL pctx->entropy means that CAVP test has been initiated on + * this socket, replace proto_ops algif_rng_ops with algif_rng_test_ops. + */ + if (IS_ENABLED(CONFIG_CRYPTO_USER_API_RNG_CAVP) && pctx->entropy) + sk->sk_socket->ops = &algif_rng_test_ops; + return 0; } static int rng_setkey(void *private, const u8 *seed, unsigned int seedlen) { + struct rng_parent_ctx *pctx = private; /* * Check whether seedlen is of sufficient size is done in RNG * implementations. */ - return crypto_rng_reset(private, seed, seedlen); + return crypto_rng_reset(pctx->drng, seed, seedlen); +} + +static int __maybe_unused rng_setentropy(void *private, sockptr_t entropy, + unsigned int len) +{ + struct rng_parent_ctx *pctx = private; + u8 *kentropy = NULL; + + if (!capable(CAP_SYS_ADMIN)) + return -EACCES; + + if (pctx->entropy) + return -EINVAL; + + if (len > MAXSIZE) + return -EMSGSIZE; + + if (len) { + kentropy = memdup_sockptr(entropy, len); + if (IS_ERR(kentropy)) + return PTR_ERR(kentropy); + } + + crypto_rng_alg(pctx->drng)->set_ent(pctx->drng, kentropy, len); + /* + * Since rng doesn't perform any memory management for the entropy + * buffer, save kentropy pointer to pctx now to free it after use. + */ + pctx->entropy = kentropy; + return 0; } static const struct af_alg_type algif_type_rng = { @@ -171,6 +319,9 @@ static const struct af_alg_type algif_type_rng = { .release = rng_release, .accept = rng_accept_parent, .setkey = rng_setkey, +#ifdef CONFIG_CRYPTO_USER_API_RNG_CAVP + .setentropy = rng_setentropy, +#endif .ops = &algif_rng_ops, .name = "rng", .owner = THIS_MODULE |