Compute and show the code signing cdhash

src/libmoex/base/digest/Sha.h

@@ -0,0 +1,128 @@
+//
+//  Created by everettjf
+//  Copyright © 2017 everettjf. All rights reserved.
+//
+// Small dependency-free SHA-1 / SHA-256 used to compute code-signing cdhash.
+// libmoex must not depend on Qt, so we cannot use QCryptographicHash here.
+#ifndef MOEX_DIGEST_SHA_H
+#define MOEX_DIGEST_SHA_H
+
+#include <cstdint>
+#include <cstddef>
+#include <string>
+#include <vector>
+
+namespace moex { namespace digest {
+
+inline std::vector<uint8_t> Sha1(const uint8_t *data, std::size_t len) {
+    uint32_t h0 = 0x67452301, h1 = 0xEFCDAB89, h2 = 0x98BADCFE, h3 = 0x10325476, h4 = 0xC3D2E1F0;
+    const uint64_t bitlen = static_cast<uint64_t>(len) * 8;
+    std::vector<uint8_t> msg(data, data + len);
+    msg.push_back(0x80);
+    while (msg.size() % 64 != 56) msg.push_back(0x00);
+    for (int i = 7; i >= 0; --i) msg.push_back(static_cast<uint8_t>(bitlen >> (i * 8)));
+
+    auto rol = [](uint32_t x, uint32_t n) { return (x << n) | (x >> (32 - n)); };
+    for (std::size_t off = 0; off < msg.size(); off += 64) {
+        uint32_t w[80];
+        for (int i = 0; i < 16; ++i)
+            w[i] = (static_cast<uint32_t>(msg[off + i * 4]) << 24) |
+                   (static_cast<uint32_t>(msg[off + i * 4 + 1]) << 16) |
+                   (static_cast<uint32_t>(msg[off + i * 4 + 2]) << 8) |
+                   static_cast<uint32_t>(msg[off + i * 4 + 3]);
+        for (int i = 16; i < 80; ++i) w[i] = rol(w[i - 3] ^ w[i - 8] ^ w[i - 14] ^ w[i - 16], 1);
+
+        uint32_t a = h0, b = h1, c = h2, d = h3, e = h4;
+        for (int i = 0; i < 80; ++i) {
+            uint32_t f, k;
+            if (i < 20) { f = (b & c) | ((~b) & d); k = 0x5A827999; }
+            else if (i < 40) { f = b ^ c ^ d; k = 0x6ED9EBA1; }
+            else if (i < 60) { f = (b & c) | (b & d) | (c & d); k = 0x8F1BBCDC; }
+            else { f = b ^ c ^ d; k = 0xCA62C1D6; }
+            const uint32_t tmp = rol(a, 5) + f + e + k + w[i];
+            e = d; d = c; c = rol(b, 30); b = a; a = tmp;
+        }
+        h0 += a; h1 += b; h2 += c; h3 += d; h4 += e;
+    }
+
+    const uint32_t hs[5] = {h0, h1, h2, h3, h4};
+    std::vector<uint8_t> out(20);
+    for (int i = 0; i < 5; ++i) {
+        out[i * 4] = static_cast<uint8_t>(hs[i] >> 24);
+        out[i * 4 + 1] = static_cast<uint8_t>(hs[i] >> 16);
+        out[i * 4 + 2] = static_cast<uint8_t>(hs[i] >> 8);
+        out[i * 4 + 3] = static_cast<uint8_t>(hs[i]);
+    }
+    return out;
+}
+
+inline std::vector<uint8_t> Sha256(const uint8_t *data, std::size_t len) {
+    static const uint32_t K[64] = {
+        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+        0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+        0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+        0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+        0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+        0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+        0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+        0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2};
+    uint32_t h[8] = {0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
+                     0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19};
+
+    const uint64_t bitlen = static_cast<uint64_t>(len) * 8;
+    std::vector<uint8_t> msg(data, data + len);
+    msg.push_back(0x80);
+    while (msg.size() % 64 != 56) msg.push_back(0x00);
+    for (int i = 7; i >= 0; --i) msg.push_back(static_cast<uint8_t>(bitlen >> (i * 8)));
+
+    auto rotr = [](uint32_t x, uint32_t n) { return (x >> n) | (x << (32 - n)); };
+    for (std::size_t off = 0; off < msg.size(); off += 64) {
+        uint32_t w[64];
+        for (int i = 0; i < 16; ++i)
+            w[i] = (static_cast<uint32_t>(msg[off + i * 4]) << 24) |
+                   (static_cast<uint32_t>(msg[off + i * 4 + 1]) << 16) |
+                   (static_cast<uint32_t>(msg[off + i * 4 + 2]) << 8) |
+                   static_cast<uint32_t>(msg[off + i * 4 + 3]);
+        for (int i = 16; i < 64; ++i) {
+            const uint32_t s0 = rotr(w[i - 15], 7) ^ rotr(w[i - 15], 18) ^ (w[i - 15] >> 3);
+            const uint32_t s1 = rotr(w[i - 2], 17) ^ rotr(w[i - 2], 19) ^ (w[i - 2] >> 10);
+            w[i] = w[i - 16] + s0 + w[i - 7] + s1;
+        }
+
+        uint32_t a = h[0], b = h[1], c = h[2], d = h[3], e = h[4], f = h[5], g = h[6], hh = h[7];
+        for (int i = 0; i < 64; ++i) {
+            const uint32_t S1 = rotr(e, 6) ^ rotr(e, 11) ^ rotr(e, 25);
+            const uint32_t ch = (e & f) ^ ((~e) & g);
+            const uint32_t t1 = hh + S1 + ch + K[i] + w[i];
+            const uint32_t S0 = rotr(a, 2) ^ rotr(a, 13) ^ rotr(a, 22);
+            const uint32_t maj = (a & b) ^ (a & c) ^ (b & c);
+            const uint32_t t2 = S0 + maj;
+            hh = g; g = f; f = e; e = d + t1; d = c; c = b; b = a; a = t1 + t2;
+        }
+        h[0] += a; h[1] += b; h[2] += c; h[3] += d; h[4] += e; h[5] += f; h[6] += g; h[7] += hh;
+    }
+
+    std::vector<uint8_t> out(32);
+    for (int i = 0; i < 8; ++i) {
+        out[i * 4] = static_cast<uint8_t>(h[i] >> 24);
+        out[i * 4 + 1] = static_cast<uint8_t>(h[i] >> 16);
+        out[i * 4 + 2] = static_cast<uint8_t>(h[i] >> 8);
+        out[i * 4 + 3] = static_cast<uint8_t>(h[i]);
+    }
+    return out;
+}
+
+inline std::string ToHex(const std::vector<uint8_t> &d) {
+    static const char *hx = "0123456789abcdef";
+    std::string s;
+    s.reserve(d.size() * 2);
+    for (uint8_t b : d) {
+        s += hx[b >> 4];
+        s += hx[b & 0x0f];
+    }
+    return s;
+}
+
+}} // namespace moex::digest
+
+#endif // MOEX_DIGEST_SHA_H

src/libmoex/viewnode/views/CodeSignatureViewNode.cpp

@@ -3,6 +3,7 @@
 //
 
 #include "CodeSignatureViewNode.h"
+#include "libmoex/base/digest/Sha.h"
 #include <cstring>
 
 MOEX_NAMESPACE_BEGIN
@@ -205,6 +206,23 @@ void CodeSignatureViewNode::InitViewDatas() {
         t->AddRow({AsAddress(base_off + cd_off), "Code Directory",
                    fmt::format("version=0x{}", AsShortHexString(cd_version))});
 
+        // cdhash: the digest of the whole Code Directory blob (per its hash
+        // type), truncated to the canonical 20 bytes.
+        const uint32_t cd_len = ReadBE32(cd + 4);
+        if (cd_len >= 8 && static_cast<uint64_t>(cd_off) + cd_len <= datasize) {
+            std::vector<uint8_t> digest;
+            if (hash_type == 1) {
+                digest = moex::digest::Sha1(cd, cd_len);
+            } else if (hash_type == 2 || hash_type == 3) {
+                digest = moex::digest::Sha256(cd, cd_len);
+            }
+            if (!digest.empty()) {
+                if (digest.size() > 20) digest.resize(20);
+                t->AddRow({AsAddress(base_off + cd_off), "CD Hash (cdhash)",
+                           moex::digest::ToHex(digest)});
+            }
+        }
+
         const std::string identifier =
                 ReadBlobCString(cd, datasize - cd_off, ident_off);
         if (!identifier.empty()) {