more efficient ca cert encoding

client/tools/gen_cert.py

@@ -0,0 +1,42 @@
+import sys
+import base64
+import re
+import hashlib
+
+with open(sys.argv[1]) as f:
+  pem_file = f.read()
+
+cert_regex = r'-----BEGIN CERTIFICATE-----\n(.+?)\n-----END CERTIFICATE-----'
+cert_template = "-----BEGIN CERTIFICATE-----\n{b64}\n-----END CERTIFICATE-----"
+certs_b64 = re.findall(cert_regex, pem_file, flags=re.S)
+certs_b64 = [s.replace("\n", "") for s in certs_b64]
+
+certs_str = "\n".join(cert_template.format(b64=s) for s in certs_b64)
+total_len = len(certs_str)
+print(hashlib.sha256(certs_str.encode()).hexdigest(), file=sys.stderr)
+
+header_part_template = """
+static uint8_t _cert_{num}[] = {array};
+"""
+header_end_template = """
+uint8_t* _certs[] = {certs_array};
+uint16_t cert_lengths[] = {lengths_array};
+uint16_t cert_count = {cert_count};
+"""
+
+header_file = "#include <stdint.h>"
+cert_lens = []
+cert_count = len(certs_b64)
+for i, cert_b64 in enumerate(certs_b64):
+  cert = base64.b64decode(cert_b64)
+  cert_lens.append(len(cert))
+  array_str = "{" + ",".join(hex(byte) for byte in cert) + "}"
+  header_file += header_part_template.format(num=i, array=array_str)
+
+header_file += header_end_template.format(
+  certs_array = "{" + ",".join(f"_cert_{i}" for i in range(cert_count)) + "}",
+  lengths_array = "{" + ",".join(str(i) for i in cert_lens) + "}",
+  cert_count=cert_count
+)
+
+print(header_file)

client/tools/generate_cert.sh

@@ -3,25 +3,16 @@
 #export ca certs to a c header file
 
 set -e
+set -x
 
-CURL_PREFIX=$(realpath build/curl-wasm)
+CURL_PREFIX="$(realpath build/curl-wasm)"
 CACERT_FILE="$(realpath build/cacert.pem)"
 CACERT_HEADER="$CURL_PREFIX/include/cacert.h"
 
-CACERT_DIR="$(dirname $CACERT_FILE)"
-REPLACE_STR="$(echo $CACERT_DIR | tr '/-' '_')"
+CACERT_DIR="$(dirname "$CACERT_FILE")"
+REPLACE_STR="$(echo "$CACERT_DIR" | tr '/-' '_')"
 
-if [ ! -f $CACERT_FILE ]; then
+if [ ! -f "$CACERT_FILE" ]; then
   wget "https://curl.se/ca/cacert.pem" -O "$CACERT_FILE"
-  #without this cert open.spotify.com does not work
-  #https://github.com/wolfSSL/wolfssl/issues/8137
-  new_cert="$(curl "https://www.certainly.com/certificates/Certainly_Intermediate_R1.pem")"
-  insert_before="Certainly Root E1"
-  replacement="$(printf "\n$new_cert\n\n$insert_before")"
-
-  cacert_str="$(cat "$CACERT_FILE")"
-  cacert_str="${cacert_str/"$insert_before"/"$replacement"}"
-  echo "$cacert_str" > $CACERT_FILE
+  python3 tools/gen_cert.py "$CACERT_FILE" > "$CACERT_HEADER"
 fi
-xxd -i $CACERT_FILE > $CACERT_HEADER
-sed -i "s/$REPLACE_STR//" $CACERT_HEADER