@@ -9,3 +9,4 @@ obj-y += lrng_pool.o lrng_aux.o \
lrng_interfaces.o
obj-$(CONFIG_NUMA) += lrng_numa.o
+obj-$(CONFIG_SYSCTL) += lrng_proc.o
@@ -38,8 +38,6 @@ static DECLARE_WAIT_QUEUE_HEAD(lrng_write_wait);
static DECLARE_WAIT_QUEUE_HEAD(lrng_init_wait);
static struct fasync_struct *fasync;
-struct ctl_table random_table[];
-
/********************************** Helper ***********************************/
/* Is the DRNG seed level too low? */
@@ -108,7 +108,11 @@ void lrng_cc20_init_state(struct chacha20_state *state);
/********************************** /proc *************************************/
+#ifdef CONFIG_SYSCTL
+void lrng_pool_inc_numa_node(void);
+#else
static inline void lrng_pool_inc_numa_node(void) { }
+#endif
/****************************** LRNG interfaces *******************************/
new file mode 100644
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+/*
+ * LRNG proc and sysctl interfaces
+ *
+ * Copyright (C) 2016 - 2021, Stephan Mueller <smueller@chronox.de>
+ */
+
+#include <linux/lrng.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/sysctl.h>
+#include <linux/uuid.h>
+
+#include "lrng_internal.h"
+#include "lrng_sw_noise.h"
+
+/*
+ * This function is used to return both the bootid UUID, and random
+ * UUID. The difference is in whether table->data is NULL; if it is,
+ * then a new UUID is generated and returned to the user.
+ *
+ * If the user accesses this via the proc interface, the UUID will be
+ * returned as an ASCII string in the standard UUID format; if via the
+ * sysctl system call, as 16 bytes of binary data.
+ */
+static int lrng_proc_do_uuid(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table fake_table;
+ unsigned char buf[64], tmp_uuid[16], *uuid;
+
+ uuid = table->data;
+ if (!uuid) {
+ uuid = tmp_uuid;
+ generate_random_uuid(uuid);
+ } else {
+ static DEFINE_SPINLOCK(bootid_spinlock);
+
+ spin_lock(&bootid_spinlock);
+ if (!uuid[8])
+ generate_random_uuid(uuid);
+ spin_unlock(&bootid_spinlock);
+ }
+
+ sprintf(buf, "%pU", uuid);
+
+ fake_table.data = buf;
+ fake_table.maxlen = sizeof(buf);
+
+ return proc_dostring(&fake_table, write, buffer, lenp, ppos);
+}
+
+static int lrng_proc_do_entropy(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table fake_table;
+ int entropy_count;
+
+ entropy_count = lrng_avail_entropy();
+
+ fake_table.data = &entropy_count;
+ fake_table.maxlen = sizeof(entropy_count);
+
+ return proc_dointvec(&fake_table, write, buffer, lenp, ppos);
+}
+
+static int lrng_proc_do_poolsize(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table fake_table;
+ int entropy_count;
+
+ /* LRNG can at most retain entropy in per-CPU pools and aux pool */
+ entropy_count = lrng_get_digestsize() + lrng_pcpu_avail_pool_size();
+
+ fake_table.data = &entropy_count;
+ fake_table.maxlen = sizeof(entropy_count);
+
+ return proc_dointvec(&fake_table, write, buffer, lenp, ppos);
+}
+
+static int lrng_min_write_thresh;
+static int lrng_max_write_thresh = LRNG_MAX_DIGESTSIZE;
+static char lrng_sysctl_bootid[16];
+static int lrng_drng_reseed_max_min;
+
+struct ctl_table random_table[] = {
+ {
+ .procname = "poolsize",
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = lrng_proc_do_poolsize,
+ },
+ {
+ .procname = "entropy_avail",
+ .maxlen = sizeof(int),
+ .mode = 0444,
+ .proc_handler = lrng_proc_do_entropy,
+ },
+ {
+ .procname = "write_wakeup_threshold",
+ .data = &lrng_write_wakeup_bits,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &lrng_min_write_thresh,
+ .extra2 = &lrng_max_write_thresh,
+ },
+ {
+ .procname = "boot_id",
+ .data = &lrng_sysctl_bootid,
+ .maxlen = 16,
+ .mode = 0444,
+ .proc_handler = lrng_proc_do_uuid,
+ },
+ {
+ .procname = "uuid",
+ .maxlen = 16,
+ .mode = 0444,
+ .proc_handler = lrng_proc_do_uuid,
+ },
+ {
+ .procname = "urandom_min_reseed_secs",
+ .data = &lrng_drng_reseed_max_time,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ .extra1 = &lrng_drng_reseed_max_min,
+ },
+ { }
+};
+
+/* Number of online DRNGs */
+static u32 numa_drngs = 1;
+
+void lrng_pool_inc_numa_node(void)
+{
+ numa_drngs++;
+}
+
+static int lrng_proc_type_show(struct seq_file *m, void *v)
+{
+ struct lrng_drng *lrng_drng_init = lrng_drng_init_instance();
+ unsigned long flags = 0;
+ unsigned char buf[390];
+
+ lrng_drng_lock(lrng_drng_init, &flags);
+ snprintf(buf, sizeof(buf),
+ "DRNG name: %s\n"
+ "Hash for reading entropy pool: %s\n"
+ "Hash for operating aux entropy pool: %s\n"
+ "LRNG security strength in bits: %d\n"
+ "per-CPU interrupt collection size: %u\n"
+ "number of DRNG instances: %u\n"
+ "SP800-90B compliance: %s\n"
+ "SP800-90C compliance: %s\n"
+ "High-resolution timer: %s\n"
+ "LRNG minimally seeded: %s\n"
+ "LRNG fully seeded: %s\n"
+ "Continuous compression: %s\n",
+ lrng_drng_init->crypto_cb->lrng_drng_name(),
+ lrng_drng_init->crypto_cb->lrng_hash_name(),
+ lrng_drng_init->crypto_cb->lrng_hash_name(),
+ lrng_security_strength(),
+ LRNG_DATA_NUM_VALUES,
+ numa_drngs,
+ lrng_sp80090b_compliant() ? "true" : "false",
+ lrng_sp80090c_compliant() ? "true" : "false",
+ lrng_pool_highres_timer() ? "true" : "false",
+ lrng_state_min_seeded() ? "true" : "false",
+ lrng_state_fully_seeded() ? "true" : "false",
+ lrng_pcpu_continuous_compression_state() ? "true" : "false");
+ lrng_drng_unlock(lrng_drng_init, &flags);
+
+ seq_write(m, buf, strlen(buf));
+
+ return 0;
+}
+
+static int __init lrng_proc_type_init(void)
+{
+ proc_create_single("lrng_type", 0444, NULL, &lrng_proc_type_show);
+ return 0;
+}
+
+module_init(lrng_proc_type_init);