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-rw-r--r--krl.c1453
1 files changed, 1453 insertions, 0 deletions
diff --git a/krl.c b/krl.c
new file mode 100644
index 0000000..3a69b63
--- /dev/null
+++ b/krl.c
@@ -0,0 +1,1453 @@
+/*
+ * Copyright (c) 2012 Damien Miller <djm@mindrot.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $OpenBSD: krl.c,v 1.51 2020/08/27 01:06:18 djm Exp $ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+#include <openbsd-compat/sys-tree.h>
+#include <openbsd-compat/sys-queue.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "sshbuf.h"
+#include "ssherr.h"
+#include "sshkey.h"
+#include "authfile.h"
+#include "misc.h"
+#include "log.h"
+#include "digest.h"
+#include "bitmap.h"
+#include "utf8.h"
+
+#include "krl.h"
+
+/* #define DEBUG_KRL */
+#ifdef DEBUG_KRL
+# define KRL_DBG(x) debug3 x
+#else
+# define KRL_DBG(x)
+#endif
+
+/*
+ * Trees of revoked serial numbers, key IDs and keys. This allows
+ * quick searching, querying and producing lists in canonical order.
+ */
+
+/* Tree of serial numbers. XXX make smarter: really need a real sparse bitmap */
+struct revoked_serial {
+ u_int64_t lo, hi;
+ RB_ENTRY(revoked_serial) tree_entry;
+};
+static int serial_cmp(struct revoked_serial *a, struct revoked_serial *b);
+RB_HEAD(revoked_serial_tree, revoked_serial);
+RB_GENERATE_STATIC(revoked_serial_tree, revoked_serial, tree_entry, serial_cmp);
+
+/* Tree of key IDs */
+struct revoked_key_id {
+ char *key_id;
+ RB_ENTRY(revoked_key_id) tree_entry;
+};
+static int key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b);
+RB_HEAD(revoked_key_id_tree, revoked_key_id);
+RB_GENERATE_STATIC(revoked_key_id_tree, revoked_key_id, tree_entry, key_id_cmp);
+
+/* Tree of blobs (used for keys and fingerprints) */
+struct revoked_blob {
+ u_char *blob;
+ size_t len;
+ RB_ENTRY(revoked_blob) tree_entry;
+};
+static int blob_cmp(struct revoked_blob *a, struct revoked_blob *b);
+RB_HEAD(revoked_blob_tree, revoked_blob);
+RB_GENERATE_STATIC(revoked_blob_tree, revoked_blob, tree_entry, blob_cmp);
+
+/* Tracks revoked certs for a single CA */
+struct revoked_certs {
+ struct sshkey *ca_key;
+ struct revoked_serial_tree revoked_serials;
+ struct revoked_key_id_tree revoked_key_ids;
+ TAILQ_ENTRY(revoked_certs) entry;
+};
+TAILQ_HEAD(revoked_certs_list, revoked_certs);
+
+struct ssh_krl {
+ u_int64_t krl_version;
+ u_int64_t generated_date;
+ u_int64_t flags;
+ char *comment;
+ struct revoked_blob_tree revoked_keys;
+ struct revoked_blob_tree revoked_sha1s;
+ struct revoked_blob_tree revoked_sha256s;
+ struct revoked_certs_list revoked_certs;
+};
+
+/* Return equal if a and b overlap */
+static int
+serial_cmp(struct revoked_serial *a, struct revoked_serial *b)
+{
+ if (a->hi >= b->lo && a->lo <= b->hi)
+ return 0;
+ return a->lo < b->lo ? -1 : 1;
+}
+
+static int
+key_id_cmp(struct revoked_key_id *a, struct revoked_key_id *b)
+{
+ return strcmp(a->key_id, b->key_id);
+}
+
+static int
+blob_cmp(struct revoked_blob *a, struct revoked_blob *b)
+{
+ int r;
+
+ if (a->len != b->len) {
+ if ((r = memcmp(a->blob, b->blob, MINIMUM(a->len, b->len))) != 0)
+ return r;
+ return a->len > b->len ? 1 : -1;
+ } else
+ return memcmp(a->blob, b->blob, a->len);
+}
+
+struct ssh_krl *
+ssh_krl_init(void)
+{
+ struct ssh_krl *krl;
+
+ if ((krl = calloc(1, sizeof(*krl))) == NULL)
+ return NULL;
+ RB_INIT(&krl->revoked_keys);
+ RB_INIT(&krl->revoked_sha1s);
+ RB_INIT(&krl->revoked_sha256s);
+ TAILQ_INIT(&krl->revoked_certs);
+ return krl;
+}
+
+static void
+revoked_certs_free(struct revoked_certs *rc)
+{
+ struct revoked_serial *rs, *trs;
+ struct revoked_key_id *rki, *trki;
+
+ RB_FOREACH_SAFE(rs, revoked_serial_tree, &rc->revoked_serials, trs) {
+ RB_REMOVE(revoked_serial_tree, &rc->revoked_serials, rs);
+ free(rs);
+ }
+ RB_FOREACH_SAFE(rki, revoked_key_id_tree, &rc->revoked_key_ids, trki) {
+ RB_REMOVE(revoked_key_id_tree, &rc->revoked_key_ids, rki);
+ free(rki->key_id);
+ free(rki);
+ }
+ sshkey_free(rc->ca_key);
+}
+
+void
+ssh_krl_free(struct ssh_krl *krl)
+{
+ struct revoked_blob *rb, *trb;
+ struct revoked_certs *rc, *trc;
+
+ if (krl == NULL)
+ return;
+
+ free(krl->comment);
+ RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_keys, trb) {
+ RB_REMOVE(revoked_blob_tree, &krl->revoked_keys, rb);
+ free(rb->blob);
+ free(rb);
+ }
+ RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_sha1s, trb) {
+ RB_REMOVE(revoked_blob_tree, &krl->revoked_sha1s, rb);
+ free(rb->blob);
+ free(rb);
+ }
+ RB_FOREACH_SAFE(rb, revoked_blob_tree, &krl->revoked_sha256s, trb) {
+ RB_REMOVE(revoked_blob_tree, &krl->revoked_sha256s, rb);
+ free(rb->blob);
+ free(rb);
+ }
+ TAILQ_FOREACH_SAFE(rc, &krl->revoked_certs, entry, trc) {
+ TAILQ_REMOVE(&krl->revoked_certs, rc, entry);
+ revoked_certs_free(rc);
+ }
+}
+
+void
+ssh_krl_set_version(struct ssh_krl *krl, u_int64_t version)
+{
+ krl->krl_version = version;
+}
+
+int
+ssh_krl_set_comment(struct ssh_krl *krl, const char *comment)
+{
+ free(krl->comment);
+ if ((krl->comment = strdup(comment)) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ return 0;
+}
+
+/*
+ * Find the revoked_certs struct for a CA key. If allow_create is set then
+ * create a new one in the tree if one did not exist already.
+ */
+static int
+revoked_certs_for_ca_key(struct ssh_krl *krl, const struct sshkey *ca_key,
+ struct revoked_certs **rcp, int allow_create)
+{
+ struct revoked_certs *rc;
+ int r;
+
+ *rcp = NULL;
+ TAILQ_FOREACH(rc, &krl->revoked_certs, entry) {
+ if ((ca_key == NULL && rc->ca_key == NULL) ||
+ sshkey_equal(rc->ca_key, ca_key)) {
+ *rcp = rc;
+ return 0;
+ }
+ }
+ if (!allow_create)
+ return 0;
+ /* If this CA doesn't exist in the list then add it now */
+ if ((rc = calloc(1, sizeof(*rc))) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ if (ca_key == NULL)
+ rc->ca_key = NULL;
+ else if ((r = sshkey_from_private(ca_key, &rc->ca_key)) != 0) {
+ free(rc);
+ return r;
+ }
+ RB_INIT(&rc->revoked_serials);
+ RB_INIT(&rc->revoked_key_ids);
+ TAILQ_INSERT_TAIL(&krl->revoked_certs, rc, entry);
+ KRL_DBG(("%s: new CA %s", __func__,
+ ca_key == NULL ? "*" : sshkey_type(ca_key)));
+ *rcp = rc;
+ return 0;
+}
+
+static int
+insert_serial_range(struct revoked_serial_tree *rt, u_int64_t lo, u_int64_t hi)
+{
+ struct revoked_serial rs, *ers, *crs, *irs;
+
+ KRL_DBG(("%s: insert %llu:%llu", __func__, lo, hi));
+ memset(&rs, 0, sizeof(rs));
+ rs.lo = lo;
+ rs.hi = hi;
+ ers = RB_NFIND(revoked_serial_tree, rt, &rs);
+ if (ers == NULL || serial_cmp(ers, &rs) != 0) {
+ /* No entry matches. Just insert */
+ if ((irs = malloc(sizeof(rs))) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ memcpy(irs, &rs, sizeof(*irs));
+ ers = RB_INSERT(revoked_serial_tree, rt, irs);
+ if (ers != NULL) {
+ KRL_DBG(("%s: bad: ers != NULL", __func__));
+ /* Shouldn't happen */
+ free(irs);
+ return SSH_ERR_INTERNAL_ERROR;
+ }
+ ers = irs;
+ } else {
+ KRL_DBG(("%s: overlap found %llu:%llu", __func__,
+ ers->lo, ers->hi));
+ /*
+ * The inserted entry overlaps an existing one. Grow the
+ * existing entry.
+ */
+ if (ers->lo > lo)
+ ers->lo = lo;
+ if (ers->hi < hi)
+ ers->hi = hi;
+ }
+
+ /*
+ * The inserted or revised range might overlap or abut adjacent ones;
+ * coalesce as necessary.
+ */
+
+ /* Check predecessors */
+ while ((crs = RB_PREV(revoked_serial_tree, rt, ers)) != NULL) {
+ KRL_DBG(("%s: pred %llu:%llu", __func__, crs->lo, crs->hi));
+ if (ers->lo != 0 && crs->hi < ers->lo - 1)
+ break;
+ /* This entry overlaps. */
+ if (crs->lo < ers->lo) {
+ ers->lo = crs->lo;
+ KRL_DBG(("%s: pred extend %llu:%llu", __func__,
+ ers->lo, ers->hi));
+ }
+ RB_REMOVE(revoked_serial_tree, rt, crs);
+ free(crs);
+ }
+ /* Check successors */
+ while ((crs = RB_NEXT(revoked_serial_tree, rt, ers)) != NULL) {
+ KRL_DBG(("%s: succ %llu:%llu", __func__, crs->lo, crs->hi));
+ if (ers->hi != (u_int64_t)-1 && crs->lo > ers->hi + 1)
+ break;
+ /* This entry overlaps. */
+ if (crs->hi > ers->hi) {
+ ers->hi = crs->hi;
+ KRL_DBG(("%s: succ extend %llu:%llu", __func__,
+ ers->lo, ers->hi));
+ }
+ RB_REMOVE(revoked_serial_tree, rt, crs);
+ free(crs);
+ }
+ KRL_DBG(("%s: done, final %llu:%llu", __func__, ers->lo, ers->hi));
+ return 0;
+}
+
+int
+ssh_krl_revoke_cert_by_serial(struct ssh_krl *krl, const struct sshkey *ca_key,
+ u_int64_t serial)
+{
+ return ssh_krl_revoke_cert_by_serial_range(krl, ca_key, serial, serial);
+}
+
+int
+ssh_krl_revoke_cert_by_serial_range(struct ssh_krl *krl,
+ const struct sshkey *ca_key, u_int64_t lo, u_int64_t hi)
+{
+ struct revoked_certs *rc;
+ int r;
+
+ if (lo > hi || lo == 0)
+ return SSH_ERR_INVALID_ARGUMENT;
+ if ((r = revoked_certs_for_ca_key(krl, ca_key, &rc, 1)) != 0)
+ return r;
+ return insert_serial_range(&rc->revoked_serials, lo, hi);
+}
+
+int
+ssh_krl_revoke_cert_by_key_id(struct ssh_krl *krl, const struct sshkey *ca_key,
+ const char *key_id)
+{
+ struct revoked_key_id *rki, *erki;
+ struct revoked_certs *rc;
+ int r;
+
+ if ((r = revoked_certs_for_ca_key(krl, ca_key, &rc, 1)) != 0)
+ return r;
+
+ KRL_DBG(("%s: revoke %s", __func__, key_id));
+ if ((rki = calloc(1, sizeof(*rki))) == NULL ||
+ (rki->key_id = strdup(key_id)) == NULL) {
+ free(rki);
+ return SSH_ERR_ALLOC_FAIL;
+ }
+ erki = RB_INSERT(revoked_key_id_tree, &rc->revoked_key_ids, rki);
+ if (erki != NULL) {
+ free(rki->key_id);
+ free(rki);
+ }
+ return 0;
+}
+
+/* Convert "key" to a public key blob without any certificate information */
+static int
+plain_key_blob(const struct sshkey *key, u_char **blob, size_t *blen)
+{
+ struct sshkey *kcopy;
+ int r;
+
+ if ((r = sshkey_from_private(key, &kcopy)) != 0)
+ return r;
+ if (sshkey_is_cert(kcopy)) {
+ if ((r = sshkey_drop_cert(kcopy)) != 0) {
+ sshkey_free(kcopy);
+ return r;
+ }
+ }
+ r = sshkey_to_blob(kcopy, blob, blen);
+ sshkey_free(kcopy);
+ return r;
+}
+
+/* Revoke a key blob. Ownership of blob is transferred to the tree */
+static int
+revoke_blob(struct revoked_blob_tree *rbt, u_char *blob, size_t len)
+{
+ struct revoked_blob *rb, *erb;
+
+ if ((rb = calloc(1, sizeof(*rb))) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ rb->blob = blob;
+ rb->len = len;
+ erb = RB_INSERT(revoked_blob_tree, rbt, rb);
+ if (erb != NULL) {
+ free(rb->blob);
+ free(rb);
+ }
+ return 0;
+}
+
+int
+ssh_krl_revoke_key_explicit(struct ssh_krl *krl, const struct sshkey *key)
+{
+ u_char *blob;
+ size_t len;
+ int r;
+
+ debug3("%s: revoke type %s", __func__, sshkey_type(key));
+ if ((r = plain_key_blob(key, &blob, &len)) != 0)
+ return r;
+ return revoke_blob(&krl->revoked_keys, blob, len);
+}
+
+static int
+revoke_by_hash(struct revoked_blob_tree *target, const u_char *p, size_t len)
+{
+ u_char *blob;
+ int r;
+
+ /* need to copy hash, as revoke_blob steals ownership */
+ if ((blob = malloc(len)) == NULL)
+ return SSH_ERR_SYSTEM_ERROR;
+ memcpy(blob, p, len);
+ if ((r = revoke_blob(target, blob, len)) != 0) {
+ free(blob);
+ return r;
+ }
+ return 0;
+}
+
+int
+ssh_krl_revoke_key_sha1(struct ssh_krl *krl, const u_char *p, size_t len)
+{
+ debug3("%s: revoke by sha1", __func__);
+ if (len != 20)
+ return SSH_ERR_INVALID_FORMAT;
+ return revoke_by_hash(&krl->revoked_sha1s, p, len);
+}
+
+int
+ssh_krl_revoke_key_sha256(struct ssh_krl *krl, const u_char *p, size_t len)
+{
+ debug3("%s: revoke by sha256", __func__);
+ if (len != 32)
+ return SSH_ERR_INVALID_FORMAT;
+ return revoke_by_hash(&krl->revoked_sha256s, p, len);
+}
+
+int
+ssh_krl_revoke_key(struct ssh_krl *krl, const struct sshkey *key)
+{
+ /* XXX replace with SHA256? */
+ if (!sshkey_is_cert(key))
+ return ssh_krl_revoke_key_explicit(krl, key);
+
+ if (key->cert->serial == 0) {
+ return ssh_krl_revoke_cert_by_key_id(krl,
+ key->cert->signature_key,
+ key->cert->key_id);
+ } else {
+ return ssh_krl_revoke_cert_by_serial(krl,
+ key->cert->signature_key,
+ key->cert->serial);
+ }
+}
+
+/*
+ * Select the most compact section type to emit next in a KRL based on
+ * the current section type, the run length of contiguous revoked serial
+ * numbers and the gaps from the last and to the next revoked serial.
+ * Applies a mostly-accurate bit cost model to select the section type
+ * that will minimise the size of the resultant KRL.
+ */
+static int
+choose_next_state(int current_state, u_int64_t contig, int final,
+ u_int64_t last_gap, u_int64_t next_gap, int *force_new_section)
+{
+ int new_state;
+ u_int64_t cost, cost_list, cost_range, cost_bitmap, cost_bitmap_restart;
+
+ /*
+ * Avoid unsigned overflows.
+ * The limits are high enough to avoid confusing the calculations.
+ */
+ contig = MINIMUM(contig, 1ULL<<31);
+ last_gap = MINIMUM(last_gap, 1ULL<<31);
+ next_gap = MINIMUM(next_gap, 1ULL<<31);
+
+ /*
+ * Calculate the cost to switch from the current state to candidates.
+ * NB. range sections only ever contain a single range, so their
+ * switching cost is independent of the current_state.
+ */
+ cost_list = cost_bitmap = cost_bitmap_restart = 0;
+ cost_range = 8;
+ switch (current_state) {
+ case KRL_SECTION_CERT_SERIAL_LIST:
+ cost_bitmap_restart = cost_bitmap = 8 + 64;
+ break;
+ case KRL_SECTION_CERT_SERIAL_BITMAP:
+ cost_list = 8;
+ cost_bitmap_restart = 8 + 64;
+ break;
+ case KRL_SECTION_CERT_SERIAL_RANGE:
+ case 0:
+ cost_bitmap_restart = cost_bitmap = 8 + 64;
+ cost_list = 8;
+ }
+
+ /* Estimate base cost in bits of each section type */
+ cost_list += 64 * contig + (final ? 0 : 8+64);
+ cost_range += (2 * 64) + (final ? 0 : 8+64);
+ cost_bitmap += last_gap + contig + (final ? 0 : MINIMUM(next_gap, 8+64));
+ cost_bitmap_restart += contig + (final ? 0 : MINIMUM(next_gap, 8+64));
+
+ /* Convert to byte costs for actual comparison */
+ cost_list = (cost_list + 7) / 8;
+ cost_bitmap = (cost_bitmap + 7) / 8;
+ cost_bitmap_restart = (cost_bitmap_restart + 7) / 8;
+ cost_range = (cost_range + 7) / 8;
+
+ /* Now pick the best choice */
+ *force_new_section = 0;
+ new_state = KRL_SECTION_CERT_SERIAL_BITMAP;
+ cost = cost_bitmap;
+ if (cost_range < cost) {
+ new_state = KRL_SECTION_CERT_SERIAL_RANGE;
+ cost = cost_range;
+ }
+ if (cost_list < cost) {
+ new_state = KRL_SECTION_CERT_SERIAL_LIST;
+ cost = cost_list;
+ }
+ if (cost_bitmap_restart < cost) {
+ new_state = KRL_SECTION_CERT_SERIAL_BITMAP;
+ *force_new_section = 1;
+ cost = cost_bitmap_restart;
+ }
+ KRL_DBG(("%s: contig %llu last_gap %llu next_gap %llu final %d, costs:"
+ "list %llu range %llu bitmap %llu new bitmap %llu, "
+ "selected 0x%02x%s", __func__, (long long unsigned)contig,
+ (long long unsigned)last_gap, (long long unsigned)next_gap, final,
+ (long long unsigned)cost_list, (long long unsigned)cost_range,
+ (long long unsigned)cost_bitmap,
+ (long long unsigned)cost_bitmap_restart, new_state,
+ *force_new_section ? " restart" : ""));
+ return new_state;
+}
+
+static int
+put_bitmap(struct sshbuf *buf, struct bitmap *bitmap)
+{
+ size_t len;
+ u_char *blob;
+ int r;
+
+ len = bitmap_nbytes(bitmap);
+ if ((blob = malloc(len)) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ if (bitmap_to_string(bitmap, blob, len) != 0) {
+ free(blob);
+ return SSH_ERR_INTERNAL_ERROR;
+ }
+ r = sshbuf_put_bignum2_bytes(buf, blob, len);
+ free(blob);
+ return r;
+}
+
+/* Generate a KRL_SECTION_CERTIFICATES KRL section */
+static int
+revoked_certs_generate(struct revoked_certs *rc, struct sshbuf *buf)
+{
+ int final, force_new_sect, r = SSH_ERR_INTERNAL_ERROR;
+ u_int64_t i, contig, gap, last = 0, bitmap_start = 0;
+ struct revoked_serial *rs, *nrs;
+ struct revoked_key_id *rki;
+ int next_state, state = 0;
+ struct sshbuf *sect;
+ struct bitmap *bitmap = NULL;
+
+ if ((sect = sshbuf_new()) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+
+ /* Store the header: optional CA scope key, reserved */
+ if (rc->ca_key == NULL) {
+ if ((r = sshbuf_put_string(buf, NULL, 0)) != 0)
+ goto out;
+ } else {
+ if ((r = sshkey_puts(rc->ca_key, buf)) != 0)
+ goto out;
+ }
+ if ((r = sshbuf_put_string(buf, NULL, 0)) != 0)
+ goto out;
+
+ /* Store the revoked serials. */
+ for (rs = RB_MIN(revoked_serial_tree, &rc->revoked_serials);
+ rs != NULL;
+ rs = RB_NEXT(revoked_serial_tree, &rc->revoked_serials, rs)) {
+ KRL_DBG(("%s: serial %llu:%llu state 0x%02x", __func__,
+ (long long unsigned)rs->lo, (long long unsigned)rs->hi,
+ state));
+
+ /* Check contiguous length and gap to next section (if any) */
+ nrs = RB_NEXT(revoked_serial_tree, &rc->revoked_serials, rs);
+ final = nrs == NULL;
+ gap = nrs == NULL ? 0 : nrs->lo - rs->hi;
+ contig = 1 + (rs->hi - rs->lo);
+
+ /* Choose next state based on these */
+ next_state = choose_next_state(state, contig, final,
+ state == 0 ? 0 : rs->lo - last, gap, &force_new_sect);
+
+ /*
+ * If the current section is a range section or has a different
+ * type to the next section, then finish it off now.
+ */
+ if (state != 0 && (force_new_sect || next_state != state ||
+ state == KRL_SECTION_CERT_SERIAL_RANGE)) {
+ KRL_DBG(("%s: finish state 0x%02x", __func__, state));
+ switch (state) {
+ case KRL_SECTION_CERT_SERIAL_LIST:
+ case KRL_SECTION_CERT_SERIAL_RANGE:
+ break;
+ case KRL_SECTION_CERT_SERIAL_BITMAP:
+ if ((r = put_bitmap(sect, bitmap)) != 0)
+ goto out;
+ bitmap_free(bitmap);
+ bitmap = NULL;
+ break;
+ }
+ if ((r = sshbuf_put_u8(buf, state)) != 0 ||
+ (r = sshbuf_put_stringb(buf, sect)) != 0)
+ goto out;
+ sshbuf_reset(sect);
+ }
+
+ /* If we are starting a new section then prepare it now */
+ if (next_state != state || force_new_sect) {
+ KRL_DBG(("%s: start state 0x%02x", __func__,
+ next_state));
+ state = next_state;
+ sshbuf_reset(sect);
+ switch (state) {
+ case KRL_SECTION_CERT_SERIAL_LIST:
+ case KRL_SECTION_CERT_SERIAL_RANGE:
+ break;
+ case KRL_SECTION_CERT_SERIAL_BITMAP:
+ if ((bitmap = bitmap_new()) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ bitmap_start = rs->lo;
+ if ((r = sshbuf_put_u64(sect,
+ bitmap_start)) != 0)
+ goto out;
+ break;
+ }
+ }
+
+ /* Perform section-specific processing */
+ switch (state) {
+ case KRL_SECTION_CERT_SERIAL_LIST:
+ for (i = 0; i < contig; i++) {
+ if ((r = sshbuf_put_u64(sect, rs->lo + i)) != 0)
+ goto out;
+ }
+ break;
+ case KRL_SECTION_CERT_SERIAL_RANGE:
+ if ((r = sshbuf_put_u64(sect, rs->lo)) != 0 ||
+ (r = sshbuf_put_u64(sect, rs->hi)) != 0)
+ goto out;
+ break;
+ case KRL_SECTION_CERT_SERIAL_BITMAP:
+ if (rs->lo - bitmap_start > INT_MAX) {
+ error("%s: insane bitmap gap", __func__);
+ goto out;
+ }
+ for (i = 0; i < contig; i++) {
+ if (bitmap_set_bit(bitmap,
+ rs->lo + i - bitmap_start) != 0) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ }
+ break;
+ }
+ last = rs->hi;
+ }
+ /* Flush the remaining section, if any */
+ if (state != 0) {
+ KRL_DBG(("%s: serial final flush for state 0x%02x",
+ __func__, state));
+ switch (state) {
+ case KRL_SECTION_CERT_SERIAL_LIST:
+ case KRL_SECTION_CERT_SERIAL_RANGE:
+ break;
+ case KRL_SECTION_CERT_SERIAL_BITMAP:
+ if ((r = put_bitmap(sect, bitmap)) != 0)
+ goto out;
+ bitmap_free(bitmap);
+ bitmap = NULL;
+ break;
+ }
+ if ((r = sshbuf_put_u8(buf, state)) != 0 ||
+ (r = sshbuf_put_stringb(buf, sect)) != 0)
+ goto out;
+ }
+ KRL_DBG(("%s: serial done ", __func__));
+
+ /* Now output a section for any revocations by key ID */
+ sshbuf_reset(sect);
+ RB_FOREACH(rki, revoked_key_id_tree, &rc->revoked_key_ids) {
+ KRL_DBG(("%s: key ID %s", __func__, rki->key_id));
+ if ((r = sshbuf_put_cstring(sect, rki->key_id)) != 0)
+ goto out;
+ }
+ if (sshbuf_len(sect) != 0) {
+ if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERT_KEY_ID)) != 0 ||
+ (r = sshbuf_put_stringb(buf, sect)) != 0)
+ goto out;
+ }
+ r = 0;
+ out:
+ bitmap_free(bitmap);
+ sshbuf_free(sect);
+ return r;
+}
+
+int
+ssh_krl_to_blob(struct ssh_krl *krl, struct sshbuf *buf,
+ struct sshkey **sign_keys, u_int nsign_keys)
+{
+ int r = SSH_ERR_INTERNAL_ERROR;
+ struct revoked_certs *rc;
+ struct revoked_blob *rb;
+ struct sshbuf *sect;
+ u_char *sblob = NULL;
+ size_t slen, i;
+
+ if (krl->generated_date == 0)
+ krl->generated_date = time(NULL);
+
+ if ((sect = sshbuf_new()) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+
+ /* Store the header */
+ if ((r = sshbuf_put(buf, KRL_MAGIC, sizeof(KRL_MAGIC) - 1)) != 0 ||
+ (r = sshbuf_put_u32(buf, KRL_FORMAT_VERSION)) != 0 ||
+ (r = sshbuf_put_u64(buf, krl->krl_version)) != 0 ||
+ (r = sshbuf_put_u64(buf, krl->generated_date)) != 0 ||
+ (r = sshbuf_put_u64(buf, krl->flags)) != 0 ||
+ (r = sshbuf_put_string(buf, NULL, 0)) != 0 ||
+ (r = sshbuf_put_cstring(buf, krl->comment)) != 0)
+ goto out;
+
+ /* Store sections for revoked certificates */
+ TAILQ_FOREACH(rc, &krl->revoked_certs, entry) {
+ sshbuf_reset(sect);
+ if ((r = revoked_certs_generate(rc, sect)) != 0)
+ goto out;
+ if ((r = sshbuf_put_u8(buf, KRL_SECTION_CERTIFICATES)) != 0 ||
+ (r = sshbuf_put_stringb(buf, sect)) != 0)
+ goto out;
+ }
+
+ /* Finally, output sections for revocations by public key/hash */
+ sshbuf_reset(sect);
+ RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_keys) {
+ KRL_DBG(("%s: key len %zu ", __func__, rb->len));
+ if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0)
+ goto out;
+ }
+ if (sshbuf_len(sect) != 0) {
+ if ((r = sshbuf_put_u8(buf, KRL_SECTION_EXPLICIT_KEY)) != 0 ||
+ (r = sshbuf_put_stringb(buf, sect)) != 0)
+ goto out;
+ }
+ sshbuf_reset(sect);
+ RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha1s) {
+ KRL_DBG(("%s: hash len %zu ", __func__, rb->len));
+ if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0)
+ goto out;
+ }
+ if (sshbuf_len(sect) != 0) {
+ if ((r = sshbuf_put_u8(buf,
+ KRL_SECTION_FINGERPRINT_SHA1)) != 0 ||
+ (r = sshbuf_put_stringb(buf, sect)) != 0)
+ goto out;
+ }
+ sshbuf_reset(sect);
+ RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha256s) {
+ KRL_DBG(("%s: hash len %zu ", __func__, rb->len));
+ if ((r = sshbuf_put_string(sect, rb->blob, rb->len)) != 0)
+ goto out;
+ }
+ if (sshbuf_len(sect) != 0) {
+ if ((r = sshbuf_put_u8(buf,
+ KRL_SECTION_FINGERPRINT_SHA256)) != 0 ||
+ (r = sshbuf_put_stringb(buf, sect)) != 0)
+ goto out;
+ }
+
+ for (i = 0; i < nsign_keys; i++) {
+ KRL_DBG(("%s: signature key %s", __func__,
+ sshkey_ssh_name(sign_keys[i])));
+ if ((r = sshbuf_put_u8(buf, KRL_SECTION_SIGNATURE)) != 0 ||
+ (r = sshkey_puts(sign_keys[i], buf)) != 0)
+ goto out;
+ /* XXX support sk-* keys */
+ if ((r = sshkey_sign(sign_keys[i], &sblob, &slen,
+ sshbuf_ptr(buf), sshbuf_len(buf), NULL, NULL,
+ NULL, 0)) != 0)
+ goto out;
+ KRL_DBG(("%s: signature sig len %zu", __func__, slen));
+ if ((r = sshbuf_put_string(buf, sblob, slen)) != 0)
+ goto out;
+ }
+
+ r = 0;
+ out:
+ free(sblob);
+ sshbuf_free(sect);
+ return r;
+}
+
+static void
+format_timestamp(u_int64_t timestamp, char *ts, size_t nts)
+{
+ time_t t;
+ struct tm *tm;
+
+ t = timestamp;
+ tm = localtime(&t);
+ if (tm == NULL)
+ strlcpy(ts, "<INVALID>", nts);
+ else {
+ *ts = '\0';
+ strftime(ts, nts, "%Y%m%dT%H%M%S", tm);
+ }
+}
+
+static int
+parse_revoked_certs(struct sshbuf *buf, struct ssh_krl *krl)
+{
+ int r = SSH_ERR_INTERNAL_ERROR;
+ u_char type;
+ const u_char *blob;
+ size_t blen, nbits;
+ struct sshbuf *subsect = NULL;
+ u_int64_t serial, serial_lo, serial_hi;
+ struct bitmap *bitmap = NULL;
+ char *key_id = NULL;
+ struct sshkey *ca_key = NULL;
+
+ if ((subsect = sshbuf_new()) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+
+ /* Header: key, reserved */
+ if ((r = sshbuf_get_string_direct(buf, &blob, &blen)) != 0 ||
+ (r = sshbuf_skip_string(buf)) != 0)
+ goto out;
+ if (blen != 0 && (r = sshkey_from_blob(blob, blen, &ca_key)) != 0)
+ goto out;
+
+ while (sshbuf_len(buf) > 0) {
+ sshbuf_free(subsect);
+ subsect = NULL;
+ if ((r = sshbuf_get_u8(buf, &type)) != 0 ||
+ (r = sshbuf_froms(buf, &subsect)) != 0)
+ goto out;
+ KRL_DBG(("%s: subsection type 0x%02x", __func__, type));
+ /* sshbuf_dump(subsect, stderr); */
+
+ switch (type) {
+ case KRL_SECTION_CERT_SERIAL_LIST:
+ while (sshbuf_len(subsect) > 0) {
+ if ((r = sshbuf_get_u64(subsect, &serial)) != 0)
+ goto out;
+ if ((r = ssh_krl_revoke_cert_by_serial(krl,
+ ca_key, serial)) != 0)
+ goto out;
+ }
+ break;
+ case KRL_SECTION_CERT_SERIAL_RANGE:
+ if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 ||
+ (r = sshbuf_get_u64(subsect, &serial_hi)) != 0)
+ goto out;
+ if ((r = ssh_krl_revoke_cert_by_serial_range(krl,
+ ca_key, serial_lo, serial_hi)) != 0)
+ goto out;
+ break;
+ case KRL_SECTION_CERT_SERIAL_BITMAP:
+ if ((bitmap = bitmap_new()) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ if ((r = sshbuf_get_u64(subsect, &serial_lo)) != 0 ||
+ (r = sshbuf_get_bignum2_bytes_direct(subsect,
+ &blob, &blen)) != 0)
+ goto out;
+ if (bitmap_from_string(bitmap, blob, blen) != 0) {
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ nbits = bitmap_nbits(bitmap);
+ for (serial = 0; serial < (u_int64_t)nbits; serial++) {
+ if (serial > 0 && serial_lo + serial == 0) {
+ error("%s: bitmap wraps u64", __func__);
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ if (!bitmap_test_bit(bitmap, serial))
+ continue;
+ if ((r = ssh_krl_revoke_cert_by_serial(krl,
+ ca_key, serial_lo + serial)) != 0)
+ goto out;
+ }
+ bitmap_free(bitmap);
+ bitmap = NULL;
+ break;
+ case KRL_SECTION_CERT_KEY_ID:
+ while (sshbuf_len(subsect) > 0) {
+ if ((r = sshbuf_get_cstring(subsect,
+ &key_id, NULL)) != 0)
+ goto out;
+ if ((r = ssh_krl_revoke_cert_by_key_id(krl,
+ ca_key, key_id)) != 0)
+ goto out;
+ free(key_id);
+ key_id = NULL;
+ }
+ break;
+ default:
+ error("Unsupported KRL certificate section %u", type);
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ if (sshbuf_len(subsect) > 0) {
+ error("KRL certificate section contains unparsed data");
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ }
+
+ r = 0;
+ out:
+ if (bitmap != NULL)
+ bitmap_free(bitmap);
+ free(key_id);
+ sshkey_free(ca_key);
+ sshbuf_free(subsect);
+ return r;
+}
+
+static int
+blob_section(struct sshbuf *sect, struct revoked_blob_tree *target_tree,
+ size_t expected_len)
+{
+ u_char *rdata = NULL;
+ size_t rlen = 0;
+ int r;
+
+ while (sshbuf_len(sect) > 0) {
+ if ((r = sshbuf_get_string(sect, &rdata, &rlen)) != 0)
+ return r;
+ if (expected_len != 0 && rlen != expected_len) {
+ error("%s: bad length", __func__);
+ free(rdata);
+ return SSH_ERR_INVALID_FORMAT;
+ }
+ if ((r = revoke_blob(target_tree, rdata, rlen)) != 0) {
+ free(rdata);
+ return r;
+ }
+ }
+ return 0;
+}
+
+/* Attempt to parse a KRL, checking its signature (if any) with sign_ca_keys. */
+int
+ssh_krl_from_blob(struct sshbuf *buf, struct ssh_krl **krlp,
+ const struct sshkey **sign_ca_keys, size_t nsign_ca_keys)
+{
+ struct sshbuf *copy = NULL, *sect = NULL;
+ struct ssh_krl *krl = NULL;
+ char timestamp[64];
+ int r = SSH_ERR_INTERNAL_ERROR, sig_seen;
+ struct sshkey *key = NULL, **ca_used = NULL, **tmp_ca_used;
+ u_char type;
+ const u_char *blob;
+ size_t i, j, sig_off, sects_off, blen, nca_used;
+ u_int format_version;
+
+ nca_used = 0;
+ *krlp = NULL;
+ if (sshbuf_len(buf) < sizeof(KRL_MAGIC) - 1 ||
+ memcmp(sshbuf_ptr(buf), KRL_MAGIC, sizeof(KRL_MAGIC) - 1) != 0) {
+ debug3("%s: not a KRL", __func__);
+ return SSH_ERR_KRL_BAD_MAGIC;
+ }
+
+ /* Take a copy of the KRL buffer so we can verify its signature later */
+ if ((copy = sshbuf_fromb(buf)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ if ((r = sshbuf_consume(copy, sizeof(KRL_MAGIC) - 1)) != 0)
+ goto out;
+
+ if ((krl = ssh_krl_init()) == NULL) {
+ error("%s: alloc failed", __func__);
+ goto out;
+ }
+
+ if ((r = sshbuf_get_u32(copy, &format_version)) != 0)
+ goto out;
+ if (format_version != KRL_FORMAT_VERSION) {
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ if ((r = sshbuf_get_u64(copy, &krl->krl_version)) != 0 ||
+ (r = sshbuf_get_u64(copy, &krl->generated_date)) != 0 ||
+ (r = sshbuf_get_u64(copy, &krl->flags)) != 0 ||
+ (r = sshbuf_skip_string(copy)) != 0 ||
+ (r = sshbuf_get_cstring(copy, &krl->comment, NULL)) != 0)
+ goto out;
+
+ format_timestamp(krl->generated_date, timestamp, sizeof(timestamp));
+ debug("KRL version %llu generated at %s%s%s",
+ (long long unsigned)krl->krl_version, timestamp,
+ *krl->comment ? ": " : "", krl->comment);
+
+ /*
+ * 1st pass: verify signatures, if any. This is done to avoid
+ * detailed parsing of data whose provenance is unverified.
+ */
+ sig_seen = 0;
+ if (sshbuf_len(buf) < sshbuf_len(copy)) {
+ /* Shouldn't happen */
+ r = SSH_ERR_INTERNAL_ERROR;
+ goto out;
+ }
+ sects_off = sshbuf_len(buf) - sshbuf_len(copy);
+ while (sshbuf_len(copy) > 0) {
+ if ((r = sshbuf_get_u8(copy, &type)) != 0 ||
+ (r = sshbuf_get_string_direct(copy, &blob, &blen)) != 0)
+ goto out;
+ KRL_DBG(("%s: first pass, section 0x%02x", __func__, type));
+ if (type != KRL_SECTION_SIGNATURE) {
+ if (sig_seen) {
+ error("KRL contains non-signature section "
+ "after signature");
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ /* Not interested for now. */
+ continue;
+ }
+ sig_seen = 1;
+ /* First string component is the signing key */
+ if ((r = sshkey_from_blob(blob, blen, &key)) != 0) {
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ if (sshbuf_len(buf) < sshbuf_len(copy)) {
+ /* Shouldn't happen */
+ r = SSH_ERR_INTERNAL_ERROR;
+ goto out;
+ }
+ sig_off = sshbuf_len(buf) - sshbuf_len(copy);
+ /* Second string component is the signature itself */
+ if ((r = sshbuf_get_string_direct(copy, &blob, &blen)) != 0) {
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ /* Check signature over entire KRL up to this point */
+ if ((r = sshkey_verify(key, blob, blen,
+ sshbuf_ptr(buf), sig_off, NULL, 0, NULL)) != 0)
+ goto out;
+ /* Check if this key has already signed this KRL */
+ for (i = 0; i < nca_used; i++) {
+ if (sshkey_equal(ca_used[i], key)) {
+ error("KRL signed more than once with "
+ "the same key");
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ }
+ /* Record keys used to sign the KRL */
+ tmp_ca_used = recallocarray(ca_used, nca_used, nca_used + 1,
+ sizeof(*ca_used));
+ if (tmp_ca_used == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ ca_used = tmp_ca_used;
+ ca_used[nca_used++] = key;
+ key = NULL;
+ }
+
+ if (sshbuf_len(copy) != 0) {
+ /* Shouldn't happen */
+ r = SSH_ERR_INTERNAL_ERROR;
+ goto out;
+ }
+
+ /*
+ * 2nd pass: parse and load the KRL, skipping the header to the point
+ * where the section start.
+ */
+ sshbuf_free(copy);
+ if ((copy = sshbuf_fromb(buf)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ if ((r = sshbuf_consume(copy, sects_off)) != 0)
+ goto out;
+ while (sshbuf_len(copy) > 0) {
+ sshbuf_free(sect);
+ sect = NULL;
+ if ((r = sshbuf_get_u8(copy, &type)) != 0 ||
+ (r = sshbuf_froms(copy, &sect)) != 0)
+ goto out;
+ KRL_DBG(("%s: second pass, section 0x%02x", __func__, type));
+
+ switch (type) {
+ case KRL_SECTION_CERTIFICATES:
+ if ((r = parse_revoked_certs(sect, krl)) != 0)
+ goto out;
+ break;
+ case KRL_SECTION_EXPLICIT_KEY:
+ if ((r = blob_section(sect,
+ &krl->revoked_keys, 0)) != 0)
+ goto out;
+ break;
+ case KRL_SECTION_FINGERPRINT_SHA1:
+ if ((r = blob_section(sect,
+ &krl->revoked_sha1s, 20)) != 0)
+ goto out;
+ break;
+ case KRL_SECTION_FINGERPRINT_SHA256:
+ if ((r = blob_section(sect,
+ &krl->revoked_sha256s, 32)) != 0)
+ goto out;
+ break;
+ case KRL_SECTION_SIGNATURE:
+ /* Handled above, but still need to stay in synch */
+ sshbuf_free(sect);
+ sect = NULL;
+ if ((r = sshbuf_skip_string(copy)) != 0)
+ goto out;
+ break;
+ default:
+ error("Unsupported KRL section %u", type);
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ if (sect != NULL && sshbuf_len(sect) > 0) {
+ error("KRL section contains unparsed data");
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ }
+
+ /* Check that the key(s) used to sign the KRL weren't revoked */
+ sig_seen = 0;
+ for (i = 0; i < nca_used; i++) {
+ if (ssh_krl_check_key(krl, ca_used[i]) == 0)
+ sig_seen = 1;
+ else {
+ sshkey_free(ca_used[i]);
+ ca_used[i] = NULL;
+ }
+ }
+ if (nca_used && !sig_seen) {
+ error("All keys used to sign KRL were revoked");
+ r = SSH_ERR_KEY_REVOKED;
+ goto out;
+ }
+
+ /* If we have CA keys, then verify that one was used to sign the KRL */
+ if (sig_seen && nsign_ca_keys != 0) {
+ sig_seen = 0;
+ for (i = 0; !sig_seen && i < nsign_ca_keys; i++) {
+ for (j = 0; j < nca_used; j++) {
+ if (ca_used[j] == NULL)
+ continue;
+ if (sshkey_equal(ca_used[j], sign_ca_keys[i])) {
+ sig_seen = 1;
+ break;
+ }
+ }
+ }
+ if (!sig_seen) {
+ r = SSH_ERR_SIGNATURE_INVALID;
+ error("KRL not signed with any trusted key");
+ goto out;
+ }
+ }
+
+ *krlp = krl;
+ r = 0;
+ out:
+ if (r != 0)
+ ssh_krl_free(krl);
+ for (i = 0; i < nca_used; i++)
+ sshkey_free(ca_used[i]);
+ free(ca_used);
+ sshkey_free(key);
+ sshbuf_free(copy);
+ sshbuf_free(sect);
+ return r;
+}
+
+/* Checks certificate serial number and key ID revocation */
+static int
+is_cert_revoked(const struct sshkey *key, struct revoked_certs *rc)
+{
+ struct revoked_serial rs, *ers;
+ struct revoked_key_id rki, *erki;
+
+ /* Check revocation by cert key ID */
+ memset(&rki, 0, sizeof(rki));
+ rki.key_id = key->cert->key_id;
+ erki = RB_FIND(revoked_key_id_tree, &rc->revoked_key_ids, &rki);
+ if (erki != NULL) {
+ KRL_DBG(("%s: revoked by key ID", __func__));
+ return SSH_ERR_KEY_REVOKED;
+ }
+
+ /*
+ * Zero serials numbers are ignored (it's the default when the
+ * CA doesn't specify one).
+ */
+ if (key->cert->serial == 0)
+ return 0;
+
+ memset(&rs, 0, sizeof(rs));
+ rs.lo = rs.hi = key->cert->serial;
+ ers = RB_FIND(revoked_serial_tree, &rc->revoked_serials, &rs);
+ if (ers != NULL) {
+ KRL_DBG(("%s: revoked serial %llu matched %llu:%llu", __func__,
+ key->cert->serial, ers->lo, ers->hi));
+ return SSH_ERR_KEY_REVOKED;
+ }
+ return 0;
+}
+
+/* Checks whether a given key/cert is revoked. Does not check its CA */
+static int
+is_key_revoked(struct ssh_krl *krl, const struct sshkey *key)
+{
+ struct revoked_blob rb, *erb;
+ struct revoked_certs *rc;
+ int r;
+
+ /* Check explicitly revoked hashes first */
+ memset(&rb, 0, sizeof(rb));
+ if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA1,
+ &rb.blob, &rb.len)) != 0)
+ return r;
+ erb = RB_FIND(revoked_blob_tree, &krl->revoked_sha1s, &rb);
+ free(rb.blob);
+ if (erb != NULL) {
+ KRL_DBG(("%s: revoked by key SHA1", __func__));
+ return SSH_ERR_KEY_REVOKED;
+ }
+ memset(&rb, 0, sizeof(rb));
+ if ((r = sshkey_fingerprint_raw(key, SSH_DIGEST_SHA256,
+ &rb.blob, &rb.len)) != 0)
+ return r;
+ erb = RB_FIND(revoked_blob_tree, &krl->revoked_sha256s, &rb);
+ free(rb.blob);
+ if (erb != NULL) {
+ KRL_DBG(("%s: revoked by key SHA256", __func__));
+ return SSH_ERR_KEY_REVOKED;
+ }
+
+ /* Next, explicit keys */
+ memset(&rb, 0, sizeof(rb));
+ if ((r = plain_key_blob(key, &rb.blob, &rb.len)) != 0)
+ return r;
+ erb = RB_FIND(revoked_blob_tree, &krl->revoked_keys, &rb);
+ free(rb.blob);
+ if (erb != NULL) {
+ KRL_DBG(("%s: revoked by explicit key", __func__));
+ return SSH_ERR_KEY_REVOKED;
+ }
+
+ if (!sshkey_is_cert(key))
+ return 0;
+
+ /* Check cert revocation for the specified CA */
+ if ((r = revoked_certs_for_ca_key(krl, key->cert->signature_key,
+ &rc, 0)) != 0)
+ return r;
+ if (rc != NULL) {
+ if ((r = is_cert_revoked(key, rc)) != 0)
+ return r;
+ }
+ /* Check cert revocation for the wildcard CA */
+ if ((r = revoked_certs_for_ca_key(krl, NULL, &rc, 0)) != 0)
+ return r;
+ if (rc != NULL) {
+ if ((r = is_cert_revoked(key, rc)) != 0)
+ return r;
+ }
+
+ KRL_DBG(("%s: %llu no match", __func__, key->cert->serial));
+ return 0;
+}
+
+int
+ssh_krl_check_key(struct ssh_krl *krl, const struct sshkey *key)
+{
+ int r;
+
+ KRL_DBG(("%s: checking key", __func__));
+ if ((r = is_key_revoked(krl, key)) != 0)
+ return r;
+ if (sshkey_is_cert(key)) {
+ debug2("%s: checking CA key", __func__);
+ if ((r = is_key_revoked(krl, key->cert->signature_key)) != 0)
+ return r;
+ }
+ KRL_DBG(("%s: key okay", __func__));
+ return 0;
+}
+
+int
+ssh_krl_file_contains_key(const char *path, const struct sshkey *key)
+{
+ struct sshbuf *krlbuf = NULL;
+ struct ssh_krl *krl = NULL;
+ int oerrno = 0, r;
+
+ if (path == NULL)
+ return 0;
+ if ((r = sshbuf_load_file(path, &krlbuf)) != 0) {
+ oerrno = errno;
+ goto out;
+ }
+ if ((r = ssh_krl_from_blob(krlbuf, &krl, NULL, 0)) != 0)
+ goto out;
+ debug2("%s: checking KRL %s", __func__, path);
+ r = ssh_krl_check_key(krl, key);
+ out:
+ sshbuf_free(krlbuf);
+ ssh_krl_free(krl);
+ if (r != 0)
+ errno = oerrno;
+ return r;
+}
+
+int
+krl_dump(struct ssh_krl *krl, FILE *f)
+{
+ struct sshkey *key = NULL;
+ struct revoked_blob *rb;
+ struct revoked_certs *rc;
+ struct revoked_serial *rs;
+ struct revoked_key_id *rki;
+ int r, ret = 0;
+ char *fp, timestamp[64];
+
+ /* Try to print in a KRL spec-compatible format */
+ format_timestamp(krl->generated_date, timestamp, sizeof(timestamp));
+ fprintf(f, "# KRL version %llu\n",
+ (unsigned long long)krl->krl_version);
+ fprintf(f, "# Generated at %s\n", timestamp);
+ if (krl->comment != NULL && *krl->comment != '\0') {
+ r = INT_MAX;
+ asmprintf(&fp, INT_MAX, &r, "%s", krl->comment);
+ fprintf(f, "# Comment: %s\n", fp);
+ free(fp);
+ }
+ fputc('\n', f);
+
+ RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_keys) {
+ if ((r = sshkey_from_blob(rb->blob, rb->len, &key)) != 0) {
+ ret = SSH_ERR_INVALID_FORMAT;
+ error("Parse key in KRL: %s", ssh_err(r));
+ continue;
+ }
+ if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT,
+ SSH_FP_DEFAULT)) == NULL) {
+ ret = SSH_ERR_INVALID_FORMAT;
+ error("sshkey_fingerprint failed");
+ continue;
+ }
+ fprintf(f, "hash: SHA256:%s # %s\n", fp, sshkey_ssh_name(key));
+ free(fp);
+ free(key);
+ }
+ RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha256s) {
+ fp = tohex(rb->blob, rb->len);
+ fprintf(f, "hash: SHA256:%s\n", fp);
+ free(fp);
+ }
+ RB_FOREACH(rb, revoked_blob_tree, &krl->revoked_sha1s) {
+ /*
+ * There is not KRL spec keyword for raw SHA1 hashes, so
+ * print them as comments.
+ */
+ fp = tohex(rb->blob, rb->len);
+ fprintf(f, "# hash SHA1:%s\n", fp);
+ free(fp);
+ }
+
+ TAILQ_FOREACH(rc, &krl->revoked_certs, entry) {
+ fputc('\n', f);
+ if (rc->ca_key == NULL)
+ fprintf(f, "# Wildcard CA\n");
+ else {
+ if ((fp = sshkey_fingerprint(rc->ca_key,
+ SSH_FP_HASH_DEFAULT, SSH_FP_DEFAULT)) == NULL) {
+ ret = SSH_ERR_INVALID_FORMAT;
+ error("sshkey_fingerprint failed");
+ continue;
+ }
+ fprintf(f, "# CA key %s %s\n",
+ sshkey_ssh_name(rc->ca_key), fp);
+ free(fp);
+ }
+ RB_FOREACH(rs, revoked_serial_tree, &rc->revoked_serials) {
+ if (rs->lo == rs->hi) {
+ fprintf(f, "serial: %llu\n",
+ (unsigned long long)rs->lo);
+ } else {
+ fprintf(f, "serial: %llu-%llu\n",
+ (unsigned long long)rs->lo,
+ (unsigned long long)rs->hi);
+ }
+ }
+ RB_FOREACH(rki, revoked_key_id_tree, &rc->revoked_key_ids) {
+ /*
+ * We don't want key IDs with embedded newlines to
+ * mess up the display.
+ */
+ r = INT_MAX;
+ asmprintf(&fp, INT_MAX, &r, "%s", rki->key_id);
+ fprintf(f, "id: %s\n", fp);
+ free(fp);
+ }
+ }
+ return ret;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-30 02:20:21 +0000