Repair CVE-2020-8284、CVE-2020-8285、CVE-2020-8286

docs/cmdline-opts/ftp-skip-pasv-ip.d

@@ -9,4 +9,6 @@ to curl's PASV command when curl connects the data connection. Instead curl
 will re-use the same IP address it already uses for the control
 connection.
 
+Since curl 7.74.0 this option is enabled by default.
+
 This option has no effect if PORT, EPRT or EPSV is used instead of PASV.

docs/libcurl/opts/CURLOPT_FTP_SKIP_PASV_IP.3

@@ -5,7 +5,7 @@
 .\" *                            | (__| |_| |  _ <| |___
 .\" *                             \___|\___/|_| \_\_____|
 .\" *
-.\" * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
+.\" * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
 .\" *
 .\" * This software is licensed as described in the file COPYING, which
 .\" * you should have received as part of this distribution. The terms
@@ -36,11 +36,13 @@ address it already uses for the control connection. But it will use the port
 number from the 227-response.
 
 This option thus allows libcurl to work around broken server installations
-that due to NATs, firewalls or incompetence report the wrong IP address back.
+that due to NATs, firewalls or incompetence report the wrong IP address
+back. Setting the option also reduces the risk for various sorts of client
+abuse by malicious servers.
 
 This option has no effect if PORT, EPRT or EPSV is used instead of PASV.
 .SH DEFAULT
-0
+1 since 7.74.0, was 0 before then.
 .SH PROTOCOLS
 FTP
 .SH EXAMPLE

lib/ftp.c

@@ -3773,129 +3773,131 @@ static CURLcode init_wc_data(struct connectdata *conn)
   return result;
 }
 
-/* This is called recursively */
 static CURLcode wc_statemach(struct connectdata *conn)
 {
   struct WildcardData * const wildcard = &(conn->data->wildcard);
   CURLcode result = CURLE_OK;
 
-  switch(wildcard->state) {
-  case CURLWC_INIT:
-    result = init_wc_data(conn);
-    if(wildcard->state == CURLWC_CLEAN)
-      /* only listing! */
-      break;
-    wildcard->state = result ? CURLWC_ERROR : CURLWC_MATCHING;
-    break;
-
-  case CURLWC_MATCHING: {
-    /* In this state is LIST response successfully parsed, so lets restore
-       previous WRITEFUNCTION callback and WRITEDATA pointer */
-    struct ftp_wc *ftpwc = wildcard->protdata;
-    conn->data->set.fwrite_func = ftpwc->backup.write_function;
-    conn->data->set.out = ftpwc->backup.file_descriptor;
-    ftpwc->backup.write_function = ZERO_NULL;
-    ftpwc->backup.file_descriptor = NULL;
-    wildcard->state = CURLWC_DOWNLOADING;
-
-    if(Curl_ftp_parselist_geterror(ftpwc->parser)) {
-      /* error found in LIST parsing */
-      wildcard->state = CURLWC_CLEAN;
-      return wc_statemach(conn);
-    }
-    if(wildcard->filelist.size == 0) {
-      /* no corresponding file */
-      wildcard->state = CURLWC_CLEAN;
-      return CURLE_REMOTE_FILE_NOT_FOUND;
-    }
-    return wc_statemach(conn);
-  }
-
-  case CURLWC_DOWNLOADING: {
-    /* filelist has at least one file, lets get first one */
-    struct ftp_conn *ftpc = &conn->proto.ftpc;
-    struct curl_fileinfo *finfo = wildcard->filelist.head->ptr;
-    struct FTP *ftp = conn->data->req.protop;
-
-    char *tmp_path = aprintf("%s%s", wildcard->path, finfo->filename);
-    if(!tmp_path)
-      return CURLE_OUT_OF_MEMORY;
-
-    /* switch default ftp->path and tmp_path */
-    free(ftp->pathalloc);
-    ftp->pathalloc = ftp->path = tmp_path;
-
-    infof(conn->data, "Wildcard - START of \"%s\"\n", finfo->filename);
-    if(conn->data->set.chunk_bgn) {
-      long userresponse;
-      Curl_set_in_callback(conn->data, true);
-      userresponse = conn->data->set.chunk_bgn(
-        finfo, wildcard->customptr, (int)wildcard->filelist.size);
-      Curl_set_in_callback(conn->data, false);
-      switch(userresponse) {
-      case CURL_CHUNK_BGN_FUNC_SKIP:
-        infof(conn->data, "Wildcard - \"%s\" skipped by user\n",
-              finfo->filename);
-        wildcard->state = CURLWC_SKIP;
-        return wc_statemach(conn);
-      case CURL_CHUNK_BGN_FUNC_FAIL:
-        return CURLE_CHUNK_FAILED;
-      }
-    }
-
-    if(finfo->filetype != CURLFILETYPE_FILE) {
-      wildcard->state = CURLWC_SKIP;
-      return wc_statemach(conn);
-    }
-
-    if(finfo->flags & CURLFINFOFLAG_KNOWN_SIZE)
-      ftpc->known_filesize = finfo->size;
-
-    result = ftp_parse_url_path(conn);
-    if(result)
+  for(;;) {
+    switch(wildcard->state) {
+    case CURLWC_INIT:
+      result = init_wc_data(conn);
+      if(wildcard->state == CURLWC_CLEAN)
+        /* only listing! */
+        return result;
+      wildcard->state = result ? CURLWC_ERROR : CURLWC_MATCHING;
       return result;
 
-    /* we don't need the Curl_fileinfo of first file anymore */
-    Curl_llist_remove(&wildcard->filelist, wildcard->filelist.head, NULL);
+    case CURLWC_MATCHING: {
+      /* In this state is LIST response successfully parsed, so lets restore
+         previous WRITEFUNCTION callback and WRITEDATA pointer */
+      struct ftp_wc *ftpwc = wildcard->protdata;
+      conn->data->set.fwrite_func = ftpwc->backup.write_function;
+      conn->data->set.out = ftpwc->backup.file_descriptor;
+      ftpwc->backup.write_function = ZERO_NULL;
+      ftpwc->backup.file_descriptor = NULL;
+      wildcard->state = CURLWC_DOWNLOADING;
 
-    if(wildcard->filelist.size == 0) { /* remains only one file to down. */
-      wildcard->state = CURLWC_CLEAN;
-      /* after that will be ftp_do called once again and no transfer
-         will be done because of CURLWC_CLEAN state */
-      return CURLE_OK;
+      if(Curl_ftp_parselist_geterror(ftpwc->parser)) {
+        /* error found in LIST parsing */
+        wildcard->state = CURLWC_CLEAN;
+        continue;
+      }
+      if(wildcard->filelist.size == 0) {
+        /* no corresponding file */
+        wildcard->state = CURLWC_CLEAN;
+        return CURLE_REMOTE_FILE_NOT_FOUND;
+      }
+      continue;
     }
-  } break;
 
-  case CURLWC_SKIP: {
-    if(conn->data->set.chunk_end) {
-      Curl_set_in_callback(conn->data, true);
-      conn->data->set.chunk_end(conn->data->wildcard.customptr);
-      Curl_set_in_callback(conn->data, false);
+    case CURLWC_DOWNLOADING: {
+      /* filelist has at least one file, lets get first one */
+      struct ftp_conn *ftpc = &conn->proto.ftpc;
+      struct curl_fileinfo *finfo = wildcard->filelist.head->ptr;
+      struct FTP *ftp = conn->data->req.protop;
+
+      char *tmp_path = aprintf("%s%s", wildcard->path, finfo->filename);
+      if(!tmp_path)
+        return CURLE_OUT_OF_MEMORY;
+
+      /* switch default ftp->path and tmp_path */
+      free(ftp->pathalloc);
+      ftp->pathalloc = ftp->path = tmp_path;
+
+      infof(conn->data, "Wildcard - START of \"%s\"\n", finfo->filename);
+      if(conn->data->set.chunk_bgn) {
+        long userresponse;
+        Curl_set_in_callback(conn->data, true);
+        userresponse = conn->data->set.chunk_bgn(
+          finfo, wildcard->customptr, (int)wildcard->filelist.size);
+        Curl_set_in_callback(conn->data, false);
+        switch(userresponse) {
+        case CURL_CHUNK_BGN_FUNC_SKIP:
+          infof(conn->data, "Wildcard - \"%s\" skipped by user\n",
+                finfo->filename);
+          wildcard->state = CURLWC_SKIP;
+          continue;
+        case CURL_CHUNK_BGN_FUNC_FAIL:
+          return CURLE_CHUNK_FAILED;
+        }
+      }
+
+      if(finfo->filetype != CURLFILETYPE_FILE) {
+        wildcard->state = CURLWC_SKIP;
+        continue;
+      }
+
+      if(finfo->flags & CURLFINFOFLAG_KNOWN_SIZE)
+        ftpc->known_filesize = finfo->size;
+
+      result = ftp_parse_url_path(conn);
+      if(result)
+        return result;
+
+      /* we don't need the Curl_fileinfo of first file anymore */
+      Curl_llist_remove(&wildcard->filelist, wildcard->filelist.head, NULL);
+
+      if(wildcard->filelist.size == 0) { /* remains only one file to down. */
+        wildcard->state = CURLWC_CLEAN;
+        /* after that will be ftp_do called once again and no transfer
+           will be done because of CURLWC_CLEAN state */
+        return CURLE_OK;
+      }
+      return result;
+    }
+
+    case CURLWC_SKIP: {
+      if(conn->data->set.chunk_end) {
+        Curl_set_in_callback(conn->data, true);
+        conn->data->set.chunk_end(conn->data->wildcard.customptr);
+        Curl_set_in_callback(conn->data, false);
+      }
+      Curl_llist_remove(&wildcard->filelist, wildcard->filelist.head, NULL);
+      wildcard->state = (wildcard->filelist.size == 0) ?
+        CURLWC_CLEAN : CURLWC_DOWNLOADING;
+      continue;
+    }
+
+    case CURLWC_CLEAN: {
+      struct ftp_wc *ftpwc = wildcard->protdata;
+      result = CURLE_OK;
+      if(ftpwc)
+        result = Curl_ftp_parselist_geterror(ftpwc->parser);
+
+      wildcard->state = result ? CURLWC_ERROR : CURLWC_DONE;
+      return result;
+    }
+
+    case CURLWC_DONE:
+    case CURLWC_ERROR:
+    case CURLWC_CLEAR:
+      if(wildcard->dtor)
+        wildcard->dtor(wildcard->protdata);
+      return result;
     }
-    Curl_llist_remove(&wildcard->filelist, wildcard->filelist.head, NULL);
-    wildcard->state = (wildcard->filelist.size == 0) ?
-                      CURLWC_CLEAN : CURLWC_DOWNLOADING;
-    return wc_statemach(conn);
   }
-
-  case CURLWC_CLEAN: {
-    struct ftp_wc *ftpwc = wildcard->protdata;
-    result = CURLE_OK;
-    if(ftpwc)
-      result = Curl_ftp_parselist_geterror(ftpwc->parser);
-
-    wildcard->state = result ? CURLWC_ERROR : CURLWC_DONE;
-  } break;
-
-  case CURLWC_DONE:
-  case CURLWC_ERROR:
-  case CURLWC_CLEAR:
-    if(wildcard->dtor)
-      wildcard->dtor(wildcard->protdata);
-    break;
-  }
-
-  return result;
+  /* UNREACHABLE */
 }
 
 /***********************************************************************

lib/url.c

@@ -456,6 +456,7 @@ CURLcode Curl_init_userdefined(struct Curl_easy *data)
   set->ftp_use_eprt = TRUE;   /* FTP defaults to EPRT operations */
   set->ftp_use_pret = FALSE;  /* mainly useful for drftpd servers */
   set->ftp_filemethod = FTPFILE_MULTICWD;
+  set->ftp_skip_ip = TRUE;    /* skip PASV IP by default */
 #endif
   set->dns_cache_timeout = 60; /* Timeout every 60 seconds by default */
 

lib/vtls/openssl.c

@@ -1717,6 +1717,11 @@ static CURLcode verifystatus(struct connectdata *conn,
   OCSP_BASICRESP *br = NULL;
   X509_STORE     *st = NULL;
   STACK_OF(X509) *ch = NULL;
+  X509 *cert;
+  OCSP_CERTID *id = NULL;
+  int cert_status, crl_reason;
+  ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd;
+  int ret;
 
   long len = SSL_get_tlsext_status_ocsp_resp(BACKEND->handle, &status);
 
@@ -1785,43 +1790,63 @@ static CURLcode verifystatus(struct connectdata *conn,
     goto end;
   }
 
-  for(i = 0; i < OCSP_resp_count(br); i++) {
-    int cert_status, crl_reason;
-    OCSP_SINGLERESP *single = NULL;
+  /* Compute the certificate's ID */
+  cert = SSL_get_peer_certificate(BACKEND->handle);
+  if(!cert) {
+    failf(data, "Error getting peer certficate");
+    result = CURLE_SSL_INVALIDCERTSTATUS;
+    goto end;
+  }
 
-    ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd;
-
-    single = OCSP_resp_get0(br, i);
-    if(!single)
-      continue;
-
-    cert_status = OCSP_single_get0_status(single, &crl_reason, &rev,
-                                          &thisupd, &nextupd);
-
-    if(!OCSP_check_validity(thisupd, nextupd, 300L, -1L)) {
-      failf(data, "OCSP response has expired");
-      result = CURLE_SSL_INVALIDCERTSTATUS;
-      goto end;
+  for(i = 0; i < sk_X509_num(ch); i++) {
+    X509 *issuer = sk_X509_value(ch, i);
+    if(X509_check_issued(issuer, cert) == X509_V_OK) {
+      id = OCSP_cert_to_id(EVP_sha1(), cert, issuer);
+      break;
     }
+  }
+  X509_free(cert);
 
-    infof(data, "SSL certificate status: %s (%d)\n",
-          OCSP_cert_status_str(cert_status), cert_status);
+  if(!id) {
+    failf(data, "Error computing OCSP ID");
+    result = CURLE_SSL_INVALIDCERTSTATUS;
+    goto end;
+  }
 
-    switch(cert_status) {
-      case V_OCSP_CERTSTATUS_GOOD:
-        break;
+  /* Find the single OCSP response corresponding to the certificate ID */
+  ret = OCSP_resp_find_status(br, id, &cert_status, &crl_reason, &rev,
+                              &thisupd, &nextupd);
+  OCSP_CERTID_free(id);
+  if(ret != 1) {
+    failf(data, "Could not find certificate ID in OCSP response");
+    result = CURLE_SSL_INVALIDCERTSTATUS;
+    goto end;
+  }
 
-      case V_OCSP_CERTSTATUS_REVOKED:
-        result = CURLE_SSL_INVALIDCERTSTATUS;
+  /* Validate the corresponding single OCSP response */
+  if(!OCSP_check_validity(thisupd, nextupd, 300L, -1L)) {
+    failf(data, "OCSP response has expired");
+    result = CURLE_SSL_INVALIDCERTSTATUS;
+    goto end;
+  }
 
-        failf(data, "SSL certificate revocation reason: %s (%d)",
-              OCSP_crl_reason_str(crl_reason), crl_reason);
-        goto end;
+  infof(data, "SSL certificate status: %s (%d)\n",
+        OCSP_cert_status_str(cert_status), cert_status);
 
-      case V_OCSP_CERTSTATUS_UNKNOWN:
-        result = CURLE_SSL_INVALIDCERTSTATUS;
-        goto end;
-    }
+  switch(cert_status) {
+  case V_OCSP_CERTSTATUS_GOOD:
+    break;
+
+  case V_OCSP_CERTSTATUS_REVOKED:
+    result = CURLE_SSL_INVALIDCERTSTATUS;
+    failf(data, "SSL certificate revocation reason: %s (%d)",
+          OCSP_crl_reason_str(crl_reason), crl_reason);
+    goto end;
+
+  case V_OCSP_CERTSTATUS_UNKNOWN:
+  default:
+    result = CURLE_SSL_INVALIDCERTSTATUS;
+    goto end;
   }
 
 end:

src/tool_cfgable.c

@@ -44,6 +44,7 @@ void config_init(struct OperationConfig* config)
   config->tcp_nodelay = TRUE; /* enabled by default */
   config->happy_eyeballs_timeout_ms = CURL_HET_DEFAULT;
   config->http09_allowed = FALSE;
+  config->ftp_skip_ip = TRUE;
 }
 
 static void free_config_fields(struct OperationConfig *config)

tests/data/test1400

@@ -76,6 +76,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_USERAGENT, "stripped");
   curl_easy_setopt(hnd, CURLOPT_MAXREDIRS, 50L);
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
 
   /* Here is a list of options the curl code used that cannot get generated

tests/data/test1401

@@ -90,6 +90,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_MAXREDIRS, 50L);
   curl_easy_setopt(hnd, CURLOPT_COOKIE, "chocolate=chip");
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
   curl_easy_setopt(hnd, CURLOPT_PROTOCOLS, (long)CURLPROTO_FILE |
                                            (long)CURLPROTO_FTP |

tests/data/test1402

@@ -81,6 +81,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_USERAGENT, "stripped");
   curl_easy_setopt(hnd, CURLOPT_MAXREDIRS, 50L);
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
 
   /* Here is a list of options the curl code used that cannot get generated

tests/data/test1403

@@ -76,6 +76,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_USERAGENT, "stripped");
   curl_easy_setopt(hnd, CURLOPT_MAXREDIRS, 50L);
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
 
   /* Here is a list of options the curl code used that cannot get generated

tests/data/test1404

@@ -147,6 +147,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_USERAGENT, "stripped");
   curl_easy_setopt(hnd, CURLOPT_MAXREDIRS, 50L);
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
 
   /* Here is a list of options the curl code used that cannot get generated

tests/data/test1405

@@ -89,6 +89,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_POSTQUOTE, slist2);
   curl_easy_setopt(hnd, CURLOPT_PREQUOTE, slist3);
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
 
   /* Here is a list of options the curl code used that cannot get generated

tests/data/test1406

@@ -79,6 +79,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_URL, "smtp://%HOSTIP:%SMTPPORT/1406");
   curl_easy_setopt(hnd, CURLOPT_UPLOAD, 1L);
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
   curl_easy_setopt(hnd, CURLOPT_MAIL_FROM, "sender@example.com");
   curl_easy_setopt(hnd, CURLOPT_MAIL_RCPT, slist1);

tests/data/test1407

@@ -62,6 +62,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_DIRLISTONLY, 1L);
   curl_easy_setopt(hnd, CURLOPT_USERPWD, "user:secret");
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
 
   /* Here is a list of options the curl code used that cannot get generated

tests/data/test1420

@@ -67,6 +67,7 @@ int main(int argc, char *argv[])
   curl_easy_setopt(hnd, CURLOPT_URL, "imap://%HOSTIP:%IMAPPORT/1420/;MAILINDEX=1");
   curl_easy_setopt(hnd, CURLOPT_USERPWD, "user:secret");
   curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+  curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 1L);
   curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
 
   /* Here is a list of options the curl code used that cannot get generated