3 files changed, 62 insertions, 2 deletions
diff --git a/src/base64.cpp b/src/base64.cpp
index bf8492e..66f512b 100644
--- a/src/base64.cpp
+++ b/src/base64.cpp
@@ -45,6 +45,12 @@ static const std::uint8_t DECODE_BASE64[128] = {
 } // namespace
 
 
+std::size_t olm::encode_base64_length(
+    std::size_t input_length
+) {
+    return 4 * ((input_length + 2) / 3) + (input_length + 2) % 3 - 2;
+}
+
 std::uint8_t * olm::encode_base64(
     std::uint8_t const * input, std::size_t input_length,
     std::uint8_t * output
diff --git a/src/message.cpp b/src/message.cpp
index 30abd9c..23ec823 100644
--- a/src/message.cpp
+++ b/src/message.cpp
@@ -136,7 +136,7 @@ static std::uint8_t const * decode(
         std::uint8_t const * len_start = pos;
         pos = varint_skip(pos, end);
         std::size_t len = varint_decode<std::size_t>(len_start, pos);
-        if (len > end - pos) return end;
+        if (len + pos > end) return end;
         value = pos;
         value_length = len;
         pos += len;
@@ -157,7 +157,7 @@ static std::uint8_t const * skip_unknown(
             std::uint8_t const * len_start = pos;
             pos = varint_skip(pos, end);
             std::size_t len = varint_decode<std::size_t>(len_start, pos);
-            if (len > end - pos) return end;
+            if (len + pos > end) return end;
             pos += len;
         } else {
             return end;
diff --git a/src/pickle.cpp b/src/pickle.cpp
index 25580d2..00f7cd4 100644
--- a/src/pickle.cpp
+++ b/src/pickle.cpp
@@ -14,6 +14,60 @@
  */
 #include "olm/pickle.hh"
 
+std::uint8_t * olm::pickle(
+    std::uint8_t * pos,
+    std::uint32_t value
+) {
+    pos += 4;
+    for (unsigned i = 4; i--;) { *(--pos) = value; value >>= 8; }
+    return pos + 4;
+}
+
+
+std::uint8_t const * olm::unpickle(
+    std::uint8_t const * pos, std::uint8_t const * end,
+    std::uint32_t & value
+) {
+    value = 0;
+    if (end < pos + 4) return end;
+    for (unsigned i = 4; i--;) { value <<= 8; value |= *(pos++); }
+    return pos;
+}
+
+std::uint8_t * olm::pickle(
+    std::uint8_t * pos,
+    bool value
+) {
+    *(pos++) = value ? 1 : 0;
+    return pos;
+}
+
+std::uint8_t const * olm::unpickle(
+    std::uint8_t const * pos, std::uint8_t const * end,
+    bool & value
+) {
+    if (pos == end) return end;
+    value = *(pos++);
+    return pos;
+}
+
+std::uint8_t * olm::pickle_bytes(
+    std::uint8_t * pos,
+    std::uint8_t const * bytes, std::size_t bytes_length
+) {
+    std::memcpy(pos, bytes, bytes_length);
+    return pos + bytes_length;
+}
+
+std::uint8_t const * olm::unpickle_bytes(
+    std::uint8_t const * pos, std::uint8_t const * end,
+    std::uint8_t * bytes, std::size_t bytes_length
+) {
+    if (end < pos + bytes_length) return end;
+    std::memcpy(bytes, pos, bytes_length);
+    return pos + bytes_length;
+}
+
 
 std::size_t olm::pickle_length(
     const olm::Curve25519PublicKey & value