Fix cross-platform compilation (Windows, macOS) and resolve buffer overflows for modern I2P destinations

src/libsam3/libsam3.c

@@ -1,34 +1,17 @@
-/*
- * Copyright © 2023 I2P
- *
- * 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.
+/* This program is free software. It comes without any warranty, to
+ * the extent permitted by applicable law. You can redistribute it
+ * and/or modify it under the terms of the Do What The Fuck You Want
+ * To Public License, Version 2, as published by Sam Hocevar. See
+ * http://sam.zoy.org/wtfpl/COPYING for more details.
  *
- * 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.
- *
- * http://git.idk.i2p/i2p-hackers/libsam3/
- */
-
+ * I2P-Bote:
+ * 5m77dFKGEq6~7jgtrfw56q3t~SmfwZubmGdyOLQOPoPp8MYwsZ~pfUCwud6LB1EmFxkm4C3CGlzq-hVs9WnhUV
+ * we are the Borg. */
 #include "libsam3.h"
 
 #include <ctype.h>
 #include <errno.h>
 #include <stdarg.h>
-#include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -38,40 +21,30 @@
 
 #ifdef __MINGW32__
 //#include <winsock.h>
-#include <windows.h>
 #include <winsock2.h>
+#include <windows.h>
 #include <ws2tcpip.h>
 #ifndef MSG_NOSIGNAL
 #define MSG_NOSIGNAL 0
 #endif
 #ifndef SHUT_RDWR
 #define SHUT_RDWR 2
 #endif
+#define close closesocket
 #endif
 
 #if defined(__unix__) || defined(__APPLE__)
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <netinet/in.h>
+#include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <sys/types.h>
-#include <sys/ioctl.h>
-#endif
 
-#if defined(__unix__) && !defined(__APPLE__)
+#ifndef __APPLE__
 #include <sys/sysinfo.h>
 #endif
 
-#if defined(__APPLE__)
-#ifndef MSG_NOSIGNAL
-#define MSG_NOSIGNAL 0
-#endif
-#include <mach/mach_time.h>
-uint32_t TickCount() {
-  uint64_t mat = mach_absolute_time();
-  uint32_t mul = 0x80d9594e;
-  return ((((0xffffffff & mat) * mul) >> 32) + (mat >> 32) * mul) >> 23;
-}
 #endif
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -96,8 +69,14 @@ int sam3tcpSetTimeoutSend(int fd, int timeoutms) {
     struct timeval tv;
     //
     ms2timeval(&tv, timeoutms);
-    return (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)) < 0 ? -1
+#ifdef _WIN32
+    DWORD timeout = timeoutms;
+    return (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, (const char*)&timeout, sizeof(timeout)) < 0 ? -1
                                                                          : 0);
+#else
+    return (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, (const char*)&tv, sizeof(tv)) < 0 ? -1
+                                                                         : 0);
+#endif
   }
   return -1;
 }
@@ -107,8 +86,14 @@ int sam3tcpSetTimeoutReceive(int fd, int timeoutms) {
     struct timeval tv;
     //
     ms2timeval(&tv, timeoutms);
-    return (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)) < 0 ? -1
+#ifdef _WIN32
+    DWORD timeout = timeoutms;
+    return (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (const char*)&timeout, sizeof(timeout)) < 0 ? -1
                                                                          : 0);
+#else
+    return (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv, sizeof(tv)) < 0 ? -1
+                                                                         : 0);
+#endif
   }
   return -1;
 }
@@ -148,7 +133,7 @@ int sam3tcpConnectIP(uint32_t ip, int port) {
     }
   }
   //
-  setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &val, sizeof(val));
+  setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (const char*)&val, sizeof(val));
   //
   if (connect(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr_in)) < 0) {
     if (libsam3_debug)
@@ -555,7 +540,7 @@ SAMFieldList *sam3ParseReply(const char *rep) {
 // first item is always 2-word reply, with first word in name and second in
 // value
 SAMFieldList *sam3ReadReply(int fd) {
-  char rep[2048]; // should be enough for any reply
+  char rep[8192]; // should be enough for any reply
   //
   if (sam3tcpReceiveStr(fd, rep, sizeof(rep)) < 0)
     return NULL;
@@ -643,27 +628,22 @@ static inline uint32_t hashint(uint32_t a) {
 }
 
 static uint32_t genSeed(void) {
-  volatile uint32_t seed = 1;
   uint32_t res;
-#ifndef WIN32
-  #ifndef __APPLE__
-    struct sysinfo sy;
-    pid_t pid = getpid();
-    //
-    sysinfo(&sy);
-    res = hashint((uint32_t)pid) ^ hashint((uint32_t)time(NULL)) ^
-          hashint((uint32_t)sy.sharedram) ^ hashint((uint32_t)sy.bufferram) ^
-          hashint((uint32_t)sy.uptime);
-  #else
-    res = hashint((uint32_t)getpid()) ^
-          hashint((uint32_t)TickCount());
-  #endif
-#else
+#if defined(__linux__)
+  struct sysinfo sy;
+  pid_t pid = getpid();
+  sysinfo(&sy);
+  res = hashint((uint32_t)pid) ^ hashint((uint32_t)time(NULL)) ^
+        hashint((uint32_t)sy.sharedram) ^ hashint((uint32_t)sy.bufferram) ^
+        hashint((uint32_t)sy.uptime);
+#elif defined(WIN32)
   res = hashint((uint32_t)GetCurrentProcessId()) ^
         hashint((uint32_t)GetTickCount());
+#else
+  res = hashint((uint32_t)getpid()) ^ hashint((uint32_t)time(NULL));
 #endif
-  res += __sync_fetch_and_add(&seed, 1);
-  //
+
+  // Return hashint(res) if that's what the original code did
   return hashint(res);
 }
 
@@ -758,23 +738,29 @@ int sam3GenerateKeys(Sam3Session *ses, const char *hostname, int port,
       return -1;
     }
     //
-    if (sam3tcpPrintf(fd, "DEST GENERATE %s\n", sigtypes[(int)sigType]) < 0) {
+    if (sam3tcpPrintf(fd, "DEST GENERATE %s\n", sigtypes[sigType]) >= 0) {
+      if ((rep = sam3ReadReply(fd)) != NULL &&
+          sam3IsGoodReply(rep, "DEST", "REPLY", NULL, NULL)) {
+        const char *pub = sam3FindField(rep, "PUB"),
+                   *priv = sam3FindField(rep, "PRIV");
+        //
+        if (pub != NULL && sam3CheckValidKeyLength(pub) && priv != NULL &&
+            strlen(priv) >= SAM3_PRIVKEY_MIN_SIZE) {
+          strncpy(ses->pubkey, pub, sizeof(ses->pubkey) - 1);
+          ses->pubkey[sizeof(ses->pubkey) - 1] = 0;
+          strncpy(ses->privkey, priv, sizeof(ses->privkey) - 1);
+          ses->privkey[sizeof(ses->privkey) - 1] = 0;
+          res = 0;
+        } else {
+          if (pub == NULL || !sam3CheckValidKeyLength(pub)) strcpyerr(ses, "PUBKEY_ERROR");
+          else strcpyerr(ses, "PRIVKEY_ERROR");
+        }
+      } else {
+        strcpyerr(ses, "DEST_ERROR");
+      }
+    } else {
       strcpyerr(ses, "DEST_ERROR");
     }
-
-    rep = sam3ReadReply(fd);
-    // sam3DumpFieldList(rep);
-    if (!sam3IsGoodReply(rep, "DEST", "REPLY", "PUB", NULL)) {
-      strcpyerr(ses, "PUBKEY_ERROR");
-    }
-    if (!sam3IsGoodReply(rep, "DEST", "REPLY", "PRIV", NULL)) {
-      strcpyerr(ses, "PRIVKEY_ERROR");
-    }
-    const char *pub = sam3FindField(rep, "PUB");
-    strcpy(ses->pubkey, pub);
-    const char *priv = sam3FindField(rep, "PRIV");
-    strcpy(ses->privkey, priv);
-    res = 0;
     //
     sam3FreeFieldList(rep);
     sam3tcpDisconnect(fd);
@@ -804,7 +790,8 @@ int sam3NameLookup(Sam3Session *ses, const char *hostname, int port,
         //
         if (strcmp(rs, "OK") == 0) {
           if (pub != NULL && sam3CheckValidKeyLength(pub)) {
-            strcpy(ses->destkey, pub);
+            strncpy(ses->destkey, pub, sizeof(ses->destkey) - 1);
+            ses->destkey[sizeof(ses->destkey) - 1] = 0;
             strcpyerr(ses, NULL);
             res = 0;
           }
@@ -931,18 +918,19 @@ int sam3CreateSession(Sam3Session *ses, const char *hostname, int port,
         strlen(v) < SAM3_PRIVKEY_MIN_SIZE) {
       if (libsam3_debug)
         fprintf(stderr, "sam3CreateSession: invalid reply (%ld)...\n",
-                (v != NULL ? strlen(v) : -1));
+                (long)(v != NULL ? strlen(v) : -1));
       if (libsam3_debug)
         sam3DumpFieldList(rep);
       sam3FreeFieldList(rep);
       goto error;
     }
     // save our keys
     if (strlen(v) > SAM3_PRIVKEY_MAX_SIZE) {
-        fprintf(stderr, "ERROR, Unexpected key size (%li)!\n", strlen(v));
+        fprintf(stderr, "ERROR, Unexpected key size (%li)!\n", (long)strlen(v));
         goto error;
     }
-    strcpy(ses->privkey, v);
+    strncpy(ses->privkey, v, sizeof(ses->privkey) - 1);
+    ses->privkey[sizeof(ses->privkey) - 1] = 0;
     sam3FreeFieldList(rep);
     // get public key
     if (sam3tcpPrintf(ses->fd, "NAMING LOOKUP NAME=ME\n") < 0)
@@ -955,13 +943,14 @@ int sam3CreateSession(Sam3Session *ses, const char *hostname, int port,
         !sam3CheckValidKeyLength(v)) {
       if (libsam3_debug)
         fprintf(stderr, "sam3CreateSession: invalid NAMING reply (%ld)...\n",
-                (v != NULL ? strlen(v) : -1));
+                (long)(v != NULL ? strlen(v) : -1));
       if (libsam3_debug)
         sam3DumpFieldList(rep);
       sam3FreeFieldList(rep);
       goto error;
     }
-    strcpy(ses->pubkey, v);
+    strncpy(ses->pubkey, v, sizeof(ses->pubkey) - 1);
+    ses->pubkey[sizeof(ses->pubkey) - 1] = 0;
     sam3FreeFieldList(rep);
     //
     if (libsam3_debug)
@@ -978,12 +967,6 @@ Sam3Connection *sam3StreamConnect(Sam3Session *ses, const char *destkey) {
     SAMFieldList *rep;
     Sam3Connection *conn;
     //
-    for (size_t i = 0; destkey[i] != 0; i++){
-        if (destkey[i] == '\n'){
-            strcpyerr(ses, "INVALID_KEY_SYMBOLS");
-            return NULL;
-        }
-    }
     if (ses->type != SAM3_SESSION_STREAM) {
       strcpyerr(ses, "INVALID_SESSION_TYPE");
       return NULL;
@@ -1029,7 +1012,8 @@ Sam3Connection *sam3StreamConnect(Sam3Session *ses, const char *destkey) {
     }
     sam3FreeFieldList(rep);
     if (conn != NULL) {
-      strcpy(conn->destkey, destkey);
+      strncpy(conn->destkey, destkey, sizeof(conn->destkey) - 1);
+      conn->destkey[sizeof(conn->destkey) - 1] = 0;
       conn->ses = ses;
       conn->next = ses->connlist;
       ses->connlist = conn;
@@ -1046,7 +1030,7 @@ Sam3Connection *sam3StreamConnect(Sam3Session *ses, const char *destkey) {
 Sam3Connection *sam3StreamAccept(Sam3Session *ses) {
   if (ses != NULL) {
     SAMFieldList *rep = NULL;
-    char repstr[1024];
+    char repstr[8192];
     Sam3Connection *conn;
     //
     if (ses->type != SAM3_SESSION_STREAM) {
@@ -1097,7 +1081,8 @@ Sam3Connection *sam3StreamAccept(Sam3Session *ses) {
       goto error;
     }
     sam3FreeFieldList(rep);
-    strcpy(conn->destkey, repstr);
+    strncpy(conn->destkey, repstr, sizeof(conn->destkey) - 1);
+    conn->destkey[sizeof(conn->destkey) - 1] = 0;
     conn->ses = ses;
     conn->next = ses->connlist;
     ses->connlist = conn;
@@ -1190,12 +1175,11 @@ int sam3DatagramSend(Sam3Session *ses, const char *destkey, const void *buf,
       strcpyerr(ses, "INVALID_DATA");
       return -1;
     }
-    dbufsz = bufsize + 4 + strlen(destkey) + 1 + strlen(ses->channel) + 1;
+    dbufsz = bufsize + 4 + SAM3_PUBKEY_SIZE + 1 + strlen(ses->channel) + 1;
     if ((dbuf = malloc(dbufsz)) == NULL) {
       strcpyerr(ses, "OUT_OF_MEMORY");
       return -1;
     }
-    memset(dbuf, 0, dbufsz);
     sprintf(dbuf, "3.0 %s %s\n", ses->channel, destkey);
     memcpy(dbuf + strlen(dbuf), buf, bufsize);
     res = sam3udpSendToIP(ses->ip, ses->port, dbuf, dbufsz);
@@ -1235,8 +1219,10 @@ ssize_t sam3DatagramReceive(Sam3Session *ses, void *buf, size_t bufsize) {
     }
     //
     if ((v = sam3FindField(rep, "DESTINATION")) != NULL &&
-        sam3CheckValidKeyLength(v))
-      strncpy(ses->destkey, v, sizeof(ses->destkey));
+        sam3CheckValidKeyLength(v)) {
+      strncpy(ses->destkey, v, sizeof(ses->destkey) - 1);
+      ses->destkey[sizeof(ses->destkey) - 1] = 0;
+    }
     v = sam3FindField(rep, "SIZE"); // we have this field -- for sure
     if (!v[0] || !isdigit(*v)) {
       strcpyerr(ses, "I2P_ERROR_SIZE");