1 files changed, 147 insertions, 0 deletions
diff --git a/src/multipart_formdata_parser.cc b/src/multipart_formdata_parser.cc
new file mode 100644
index 0000000..6802bc8
--- /dev/null
+++ b/src/multipart_formdata_parser.cc
@@ -0,0 +1,147 @@
+#include "common.hh"
+
+#include <algorithm>
+
+#include "header_parser.hh"
+#include "multipart_formdata_parser.hh"
+#include "strutils.hh"
+
+namespace stuff {
+
+namespace {
+
+template<typename Iterator>
+Iterator find_boundary(Iterator begin, Iterator end,
+                       const std::string& boundary,
+                       bool* last) {
+    Iterator start, test;
+    for (auto it = begin; it != end; ++it) {
+        if (it == begin && *it == '-') {
+            start = it;
+            test = it + 1;
+            if (test == end || *test != '-') continue;
+        } else if (*it == '\r') {
+            start = it;
+            test = it + 1;
+            if (test == end || *test != '\n') continue;
+            ++test;
+            if (test == end || *test != '-') continue;
+            ++test;
+            if (test == end || *test != '-') continue;
+        } else {
+            continue;
+        }
+        ++test;
+        if (static_cast<size_t>(end - test) <= boundary.size()) return end;
+        if (boundary.compare(0, std::string::npos,
+                             &(*test), boundary.size()) == 0) {
+            test += boundary.size();
+            if (test == end) return end;
+            if (*test == '-') {
+                ++test;
+                if (test == end || *test != '-') continue;
+                *last = true;
+                return start;
+            } else if (*test == '\r') {
+                ++test;
+                if (test == end || *test != '\n') continue;
+                *last = false;
+                return start;
+            }
+        }
+    }
+    return end;
+}
+
+template<typename Iterator>
+bool parse_part(Iterator begin, Iterator end,
+                std::map<std::string, std::string>* out) {
+    static const char EOL[] = "\r\n";
+    bool have_name = false, ok_contenttype = true, ok_encoding = true,
+        ok_content = true;
+    std::string name;
+    while (true) {
+        auto eol = std::search(begin, end, EOL, EOL + 2);
+        if (eol == end) return false;
+        if (eol == begin) {
+            begin += 2;
+            break;
+        }
+        auto colon = std::find(begin, eol, ':');
+        if (colon == eol) return false;
+        std::string header =
+            ascii_tolower(std::string(&(*begin), colon - begin));
+        ++colon;
+        if (colon == eol) return false;
+        if (header == "content-disposition" || header == "content-type" ||
+            header == "content-transfer-encoding") {
+            std::string token;
+            std::map<std::string, std::string> params;
+            std::string value = std::string(&(*colon), eol - colon);
+            if (!HeaderParser::parse(std::string(&(*colon), eol - colon),
+                                     &token, &params)) return false;
+            if (header[9] == 'i') {  // content-disposition
+                if (token == "form-data") {
+                    auto it = params.find("name");
+                    if (it == params.end()) return false;
+                    have_name = true;
+                    name = it->second;
+                    ok_content = true;
+                } else {
+                    ok_content = false;
+                }
+            } else if (header[9] == 'y') {  // content-type
+                auto pos = token.find('/');
+                if (pos == std::string::npos) return false;
+                ok_contenttype = true;
+                if (token.compare(0, pos, "text") != 0) ok_contenttype = false;
+                if (ok_contenttype) {
+                    auto it = params.find("charset");
+                    if (it != params.end()) {
+                        std::string charset = ascii_tolower(it->second);
+                        ok_contenttype = charset == "ascii" ||
+                            charset == "us-ascii" ||
+                            charset == "utf-8";
+                    }
+                }
+            } else /* if (header[9] == 'r') */ {  // content-transfer-encoding
+                ok_encoding = token == "7bit" || token == "8bit" ||
+                    token == "binary" || token == "identity";
+            }
+        }
+        begin = eol + 2;
+    }
+    if (have_name && ok_contenttype && ok_encoding && ok_content) {
+        (*out)[name] = std::string(&(*begin), end - begin);
+    }
+    return true;
+}
+
+}  // namespace
+
+bool MultipartFormDataParser::parse(const std::vector<char>& in,
+                                    const std::string& boundary,
+                                    std::map<std::string, std::string>* out) {
+    bool last;
+    auto start = find_boundary(in.begin(), in.end(), boundary, &last);
+    out->clear();
+    if (start == in.end()) return in.empty();
+    if (last) return true;
+    if (*start != '-') start += 2;
+    while (true)
+    {
+        start += boundary.size() + 4;
+        auto end = find_boundary(start, in.end(), boundary, &last);
+        if (end == in.end()) return false;
+
+        if (!parse_part(start, end, out)) {
+            return false;
+        }
+
+        if (last) return true;
+
+        start = end + 2;
+    }
+}
+
+}  // namespace stuff