1 files changed, 387 insertions, 0 deletions

diff --git a/src/lib/libssl/bs_cbb.c b/src/lib/libssl/bs_cbb.c
new file mode 100644
index 0000000000..668231c1c7
--- /dev/null
+++ b/src/lib/libssl/bs_cbb.c
@@ -0,0 +1,387 @@
+/*      $OpenBSD: bs_cbb.c,v 1.1 2015/02/06 09:36:16 doug Exp $ */
+/*
+ * Copyright (c) 2014, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or 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. */
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <openssl/opensslconf.h>
+
+#include "bytestring.h"
+
+static int cbb_init(CBB *cbb, uint8_t *buf, size_t cap) {
+  struct cbb_buffer_st *base;
+
+  base = malloc(sizeof(struct cbb_buffer_st));
+  if (base == NULL) {
+    free(buf);
+    return 0;
+  }
+
+  base->buf = buf;
+  base->len = 0;
+  base->cap = cap;
+  base->can_resize = 1;
+
+  memset(cbb, 0, sizeof(CBB));
+  cbb->base = base;
+  cbb->is_top_level = 1;
+  return 1;
+}
+
+int CBB_init(CBB *cbb, size_t initial_capacity) {
+  uint8_t *buf;
+
+  buf = malloc(initial_capacity);
+  if (initial_capacity > 0 && buf == NULL) {
+    return 0;
+  }
+
+  return cbb_init(cbb, buf, initial_capacity);
+}
+
+int CBB_init_fixed(CBB *cbb, uint8_t *buf, size_t len) {
+  if (!cbb_init(cbb, buf, len)) {
+    return 0;
+  }
+
+  cbb->base->can_resize = 0;
+  return 1;
+}
+
+void CBB_cleanup(CBB *cbb) {
+  if (cbb->base) {
+    if (cbb->base->buf && cbb->base->can_resize) {
+      free(cbb->base->buf);
+    }
+    free(cbb->base);
+  }
+  cbb->base = NULL;
+}
+
+static int cbb_buffer_add(struct cbb_buffer_st *base, uint8_t **out,
+                          size_t len) {
+  size_t newlen;
+
+  if (base == NULL) {
+    return 0;
+  }
+
+#if 0
+  // XXX Added for boringssl patch testing
+  if (len == 0) {
+          if (out) {
+                  *out = NULL;
+          }
+          return 1;
+  }
+#endif
+
+  newlen = base->len + len;
+  if (newlen < base->len) {
+    /* Overflow */
+    return 0;
+  }
+
+  if (newlen > base->cap) {
+    size_t newcap = base->cap * 2;
+    uint8_t *newbuf;
+
+    if (!base->can_resize) {
+      return 0;
+    }
+
+    if (newcap < base->cap || newcap < newlen) {
+      newcap = newlen;
+    }
+    newbuf = realloc(base->buf, newcap);
+    if (newbuf == NULL) {
+      return 0;
+    }
+
+    base->buf = newbuf;
+    base->cap = newcap;
+  }
+
+  if (out) {
+    *out = base->buf + base->len;
+  }
+  base->len = newlen;
+  return 1;
+}
+
+static int cbb_buffer_add_u(struct cbb_buffer_st *base, uint32_t v,
+                            size_t len_len) {
+  uint8_t *buf;
+  size_t i;
+
+  if (len_len == 0) {
+    return 1;
+  }
+  if (!cbb_buffer_add(base, &buf, len_len)) {
+    return 0;
+  }
+
+  for (i = len_len - 1; i < len_len; i--) {
+    buf[i] = v;
+    v >>= 8;
+  }
+  return 1;
+}
+
+int CBB_finish(CBB *cbb, uint8_t **out_data, size_t *out_len) {
+  if (!cbb->is_top_level) {
+    return 0;
+  }
+
+  if (!CBB_flush(cbb)) {
+    return 0;
+  }
+
+  if (cbb->base->can_resize && (out_data == NULL || out_len == NULL)) {
+    /* |out_data| and |out_len| can only be NULL if the CBB is fixed. */
+    return 0;
+  }
+
+  if (out_data != NULL) {
+    *out_data = cbb->base->buf;
+  }
+  if (out_len != NULL) {
+    *out_len = cbb->base->len;
+  }
+  cbb->base->buf = NULL;
+  CBB_cleanup(cbb);
+  return 1;
+}
+
+/* CBB_flush recurses and then writes out any pending length prefix. The
+ * current length of the underlying base is taken to be the length of the
+ * length-prefixed data. */
+int CBB_flush(CBB *cbb) {
+  size_t child_start, i, len;
+
+  if (cbb->base == NULL) {
+    return 0;
+  }
+
+  if (cbb->child == NULL || cbb->pending_len_len == 0) {
+    return 1;
+  }
+
+  child_start = cbb->offset + cbb->pending_len_len;
+
+  if (!CBB_flush(cbb->child) ||
+      child_start < cbb->offset ||
+      cbb->base->len < child_start) {
+    return 0;
+  }
+
+  len = cbb->base->len - child_start;
+
+  if (cbb->pending_is_asn1) {
+    /* For ASN.1 we assume that we'll only need a single byte for the length.
+     * If that turned out to be incorrect, we have to move the contents along
+     * in order to make space. */
+    size_t len_len;
+    uint8_t initial_length_byte;
+
+    assert (cbb->pending_len_len == 1);
+
+    if (len > 0xfffffffe) {
+      /* Too large. */
+      return 0;
+    } else if (len > 0xffffff) {
+      len_len = 5;
+      initial_length_byte = 0x80 | 4;
+    } else if (len > 0xffff) {
+      len_len = 4;
+      initial_length_byte = 0x80 | 3;
+    } else if (len > 0xff) {
+      len_len = 3;
+      initial_length_byte = 0x80 | 2;
+    } else if (len > 0x7f) {
+      len_len = 2;
+      initial_length_byte = 0x80 | 1;
+    } else {
+      len_len = 1;
+      initial_length_byte = len;
+      len = 0;
+    }
+
+    if (len_len != 1) {
+      /* We need to move the contents along in order to make space. */
+      size_t extra_bytes = len_len - 1;
+      if (!cbb_buffer_add(cbb->base, NULL, extra_bytes)) {
+        return 0;
+      }
+      memmove(cbb->base->buf + child_start + extra_bytes,
+              cbb->base->buf + child_start, len);
+    }
+    cbb->base->buf[cbb->offset++] = initial_length_byte;
+    cbb->pending_len_len = len_len - 1;
+  }
+
+  for (i = cbb->pending_len_len - 1; i < cbb->pending_len_len; i--) {
+    cbb->base->buf[cbb->offset + i] = len;
+    len >>= 8;
+  }
+  if (len != 0) {
+    return 0;
+  }
+
+  cbb->child->base = NULL;
+  cbb->child = NULL;
+  cbb->pending_len_len = 0;
+  cbb->pending_is_asn1 = 0;
+  cbb->offset = 0;
+
+  return 1;
+}
+
+
+static int cbb_add_length_prefixed(CBB *cbb, CBB *out_contents,
+                                   size_t len_len) {
+  uint8_t *prefix_bytes;
+
+  if (!CBB_flush(cbb)) {
+    return 0;
+  }
+
+  cbb->offset = cbb->base->len;
+  if (!cbb_buffer_add(cbb->base, &prefix_bytes, len_len)) {
+    return 0;
+  }
+
+  memset(prefix_bytes, 0, len_len);
+  memset(out_contents, 0, sizeof(CBB));
+  out_contents->base = cbb->base;
+  cbb->child = out_contents;
+  cbb->pending_len_len = len_len;
+  cbb->pending_is_asn1 = 0;
+
+  return 1;
+}
+
+int CBB_add_u8_length_prefixed(CBB *cbb, CBB *out_contents) {
+  return cbb_add_length_prefixed(cbb, out_contents, 1);
+}
+
+int CBB_add_u16_length_prefixed(CBB *cbb, CBB *out_contents) {
+  return cbb_add_length_prefixed(cbb, out_contents, 2);
+}
+
+int CBB_add_u24_length_prefixed(CBB *cbb, CBB *out_contents) {
+  return cbb_add_length_prefixed(cbb, out_contents, 3);
+}
+
+int CBB_add_asn1(CBB *cbb, CBB *out_contents, uint8_t tag) {
+  if (!CBB_flush(cbb) ||
+      !CBB_add_u8(cbb, tag)) {
+    return 0;
+  }
+
+  cbb->offset = cbb->base->len;
+  if (!CBB_add_u8(cbb, 0)) {
+    return 0;
+  }
+
+  memset(out_contents, 0, sizeof(CBB));
+  out_contents->base = cbb->base;
+  cbb->child = out_contents;
+  cbb->pending_len_len = 1;
+  cbb->pending_is_asn1 = 1;
+
+  return 1;
+}
+
+int CBB_add_bytes(CBB *cbb, const uint8_t *data, size_t len) {
+  uint8_t *dest;
+
+  if (!CBB_flush(cbb) ||
+      !cbb_buffer_add(cbb->base, &dest, len)) {
+    return 0;
+  }
+  memcpy(dest, data, len);
+  return 1;
+}
+
+int CBB_add_space(CBB *cbb, uint8_t **out_data, size_t len) {
+  if (!CBB_flush(cbb) ||
+      !cbb_buffer_add(cbb->base, out_data, len)) {
+    return 0;
+  }
+  return 1;
+}
+
+int CBB_add_u8(CBB *cbb, uint8_t value) {
+  if (!CBB_flush(cbb)) {
+    return 0;
+  }
+
+  return cbb_buffer_add_u(cbb->base, value, 1);
+}
+
+int CBB_add_u16(CBB *cbb, uint16_t value) {
+  if (!CBB_flush(cbb)) {
+    return 0;
+  }
+
+  return cbb_buffer_add_u(cbb->base, value, 2);
+}
+
+int CBB_add_u24(CBB *cbb, uint32_t value) {
+  if (!CBB_flush(cbb)) {
+    return 0;
+  }
+
+  return cbb_buffer_add_u(cbb->base, value, 3);
+}
+
+int CBB_add_asn1_uint64(CBB *cbb, uint64_t value) {
+  CBB child;
+  size_t i;
+  int started = 0;
+
+  if (!CBB_add_asn1(cbb, &child, CBS_ASN1_INTEGER)) {
+    return 0;
+  }
+
+  for (i = 0; i < 8; i++) {
+    uint8_t byte = (value >> 8*(7-i)) & 0xff;
+    if (!started) {
+      if (byte == 0) {
+        /* Don't encode leading zeros. */
+        continue;
+      }
+      /* If the high bit is set, add a padding byte to make it
+       * unsigned. */
+      if ((byte & 0x80) && !CBB_add_u8(&child, 0)) {
+        return 0;
+      }
+      started = 1;
+    }
+    if (!CBB_add_u8(&child, byte)) {
+      return 0;
+    }
+  }
+
+  /* 0 is encoded as a single 0, not the empty string. */
+  if (!started && !CBB_add_u8(&child, 0)) {
+    return 0;
+  }
+
+  return CBB_flush(cbb);
+}