1 files changed, 205 insertions, 0 deletions
diff --git a/web/server/h2o/libh2o/lib/http2/casper.c b/web/server/h2o/libh2o/lib/http2/casper.c
new file mode 100644
index 00000000..56e00d71
--- /dev/null
+++ b/web/server/h2o/libh2o/lib/http2/casper.c
@@ -0,0 +1,205 @@
+/*
+ * Copyright (c) 2015 DeNA Co., Ltd., Kazuho Oku
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#include <openssl/sha.h>
+#include "golombset.h"
+#include "h2o/string_.h"
+#include "h2o/http2_casper.h"
+
+#define COOKIE_NAME "h2o_casper"
+#define COOKIE_ATTRIBUTES "; Path=/; Expires=Tue, 01 Jan 2030 00:00:00 GMT; Secure"
+
+struct st_h2o_http2_casper_t {
+    H2O_VECTOR(uint64_t) keys;
+    unsigned capacity_bits;
+    unsigned remainder_bits;
+    h2o_iovec_t cookie_cache;
+};
+
+static unsigned calc_key(h2o_http2_casper_t *casper, const char *path, size_t path_len)
+{
+    SHA_CTX ctx;
+    SHA1_Init(&ctx);
+    SHA1_Update(&ctx, path, path_len);
+
+    union {
+        unsigned key;
+        unsigned char bytes[SHA_DIGEST_LENGTH];
+    } md;
+    SHA1_Final(md.bytes, &ctx);
+
+    return md.key & ((1 << casper->capacity_bits) - 1);
+}
+
+h2o_http2_casper_t *h2o_http2_casper_create(unsigned capacity_bits, unsigned remainder_bits)
+{
+    h2o_http2_casper_t *casper = h2o_mem_alloc(sizeof(*casper));
+
+    memset(&casper->keys, 0, sizeof(casper->keys));
+    casper->capacity_bits = capacity_bits;
+    casper->remainder_bits = remainder_bits;
+    casper->cookie_cache = (h2o_iovec_t){NULL};
+
+    return casper;
+}
+
+void h2o_http2_casper_destroy(h2o_http2_casper_t *casper)
+{
+    free(casper->keys.entries);
+    free(casper->cookie_cache.base);
+    free(casper);
+}
+
+size_t h2o_http2_casper_num_entries(h2o_http2_casper_t *casper)
+{
+    return casper->keys.size;
+}
+
+int h2o_http2_casper_lookup(h2o_http2_casper_t *casper, const char *path, size_t path_len, int set)
+{
+    unsigned key = calc_key(casper, path, path_len);
+    size_t i;
+
+    /* FIXME use binary search */
+    for (i = 0; i != casper->keys.size; ++i)
+        if (key <= casper->keys.entries[i])
+            break;
+    if (i != casper->keys.size && key == casper->keys.entries[i])
+        return 1;
+    if (!set)
+        return 0;
+
+    /* we need to set a new value */
+    free(casper->cookie_cache.base);
+    casper->cookie_cache = (h2o_iovec_t){NULL};
+    h2o_vector_reserve(NULL, &casper->keys, casper->keys.size + 1);
+    memmove(casper->keys.entries + i + 1, casper->keys.entries + i, (casper->keys.size - i) * sizeof(casper->keys.entries[0]));
+    ++casper->keys.size;
+    casper->keys.entries[i] = key;
+    return 0;
+}
+
+void h2o_http2_casper_consume_cookie(h2o_http2_casper_t *casper, const char *cookie, size_t cookie_len)
+{
+    h2o_iovec_t binary = {NULL};
+    uint64_t tiny_keys_buf[128], *keys = tiny_keys_buf;
+
+    /* check the name of the cookie */
+    if (!(cookie_len > sizeof(COOKIE_NAME "=") - 1 && memcmp(cookie, H2O_STRLIT(COOKIE_NAME "=")) == 0))
+        goto Exit;
+
+    /* base64 decode */
+    if ((binary = h2o_decode_base64url(NULL, cookie + sizeof(COOKIE_NAME "=") - 1, cookie_len - (sizeof(COOKIE_NAME "=") - 1)))
+            .base == NULL)
+        goto Exit;
+
+    /* decode GCS, either using tiny_keys_buf or using heap */
+    size_t capacity = sizeof(tiny_keys_buf) / sizeof(tiny_keys_buf[0]), num_keys;
+    while (num_keys = capacity, golombset_decode(casper->remainder_bits, binary.base, binary.len, keys, &num_keys) != 0) {
+        if (keys != tiny_keys_buf) {
+            free(keys);
+            keys = tiny_keys_buf; /* reset to something that would not trigger call to free(3) */
+        }
+        if (capacity >= (size_t)1 << casper->capacity_bits)
+            goto Exit;
+        capacity *= 2;
+        keys = h2o_mem_alloc(capacity * sizeof(*keys));
+    }
+
+    /* copy or merge the entries */
+    if (num_keys == 0) {
+        /* nothing to do */
+    } else if (casper->keys.size == 0) {
+        h2o_vector_reserve(NULL, &casper->keys, num_keys);
+        memcpy(casper->keys.entries, keys, num_keys * sizeof(*keys));
+        casper->keys.size = num_keys;
+    } else {
+        uint64_t *orig_keys = casper->keys.entries;
+        size_t num_orig_keys = casper->keys.size, orig_index = 0, new_index = 0;
+        memset(&casper->keys, 0, sizeof(casper->keys));
+        h2o_vector_reserve(NULL, &casper->keys, num_keys + num_orig_keys);
+        do {
+            if (orig_keys[orig_index] < keys[new_index]) {
+                casper->keys.entries[casper->keys.size++] = orig_keys[orig_index++];
+            } else if (orig_keys[orig_index] > keys[new_index]) {
+                casper->keys.entries[casper->keys.size++] = keys[new_index++];
+            } else {
+                casper->keys.entries[casper->keys.size++] = orig_keys[orig_index];
+                ++orig_index;
+                ++new_index;
+            }
+        } while (orig_index != num_orig_keys && new_index != num_keys);
+        if (orig_index != num_orig_keys) {
+            do {
+                casper->keys.entries[casper->keys.size++] = orig_keys[orig_index++];
+            } while (orig_index != num_orig_keys);
+        } else if (new_index != num_keys) {
+            do {
+                casper->keys.entries[casper->keys.size++] = keys[new_index++];
+            } while (new_index != num_keys);
+        }
+        free(orig_keys);
+    }
+
+Exit:
+    if (keys != tiny_keys_buf)
+        free(keys);
+    free(binary.base);
+}
+
+static size_t append_str(char *dst, const char *s, size_t l)
+{
+    memcpy(dst, s, l);
+    return l;
+}
+
+h2o_iovec_t h2o_http2_casper_get_cookie(h2o_http2_casper_t *casper)
+{
+    if (casper->cookie_cache.base != NULL)
+        return casper->cookie_cache;
+
+    if (casper->keys.size == 0)
+        return (h2o_iovec_t){NULL};
+
+    /* encode as binary */
+    char tiny_bin_buf[128], *bin_buf = tiny_bin_buf;
+    size_t bin_capacity = sizeof(tiny_bin_buf), bin_size;
+    while (bin_size = bin_capacity,
+           golombset_encode(casper->remainder_bits, casper->keys.entries, casper->keys.size, bin_buf, &bin_size) != 0) {
+        if (bin_buf != tiny_bin_buf)
+            free(bin_buf);
+        bin_capacity *= 2;
+        bin_buf = h2o_mem_alloc(bin_capacity);
+    }
+
+    char *header_bytes = h2o_mem_alloc(sizeof(COOKIE_NAME "=" COOKIE_ATTRIBUTES) - 1 + (bin_size + 3) * 4 / 3);
+    size_t header_len = 0;
+
+    header_len += append_str(header_bytes + header_len, H2O_STRLIT(COOKIE_NAME "="));
+    header_len += h2o_base64_encode(header_bytes + header_len, bin_buf, bin_size, 1);
+    header_len += append_str(header_bytes + header_len, H2O_STRLIT(COOKIE_ATTRIBUTES));
+
+    if (bin_buf != tiny_bin_buf)
+        free(bin_buf);
+
+    casper->cookie_cache = h2o_iovec_init(header_bytes, header_len);
+    return casper->cookie_cache;
+}