nanocoap_vfs: add nanocoap_vfs_get()

examples/suit_update/Makefile

@@ -106,7 +106,7 @@ include $(RIOTBASE)/Makefile.include
 # allow to use large blocks to utilize large MTUs (802.15.4g, Ethernet, WiFi)
 LARGE_BLOCKS ?= 0
 ifeq (1, $(LARGE_BLOCKS))
-  CFLAGS += -DCONFIG_SUIT_COAP_BLOCKSIZE=COAP_BLOCKSIZE_1024
+  CFLAGS += -DCONFIG_NANOCOAP_BLOCKSIZE_DEFAULT=COAP_BLOCKSIZE_1024
 else
 # lower pktbuf size to something sufficient for this application
 # Set GNRC_PKTBUF_SIZE via CFLAGS if not being set via Kconfig.

sys/Makefile.dep

@@ -682,6 +682,11 @@ ifneq (,$(filter nanocoap_cache,$(USEMODULE)))
   USEMODULE += hashes
 endif
 
+ifneq (,$(filter nanocoap_vfs,$(USEMODULE)))
+  USEMODULE += nanocoap_sock
+  USEMODULE += vfs
+endif
+
 ifneq (,$(filter nanocoap_%,$(USEMODULE)))
   USEMODULE += nanocoap
 endif

sys/include/net/nanocoap.h

@@ -148,6 +148,13 @@ extern "C" {
 #define CONFIG_NANOCOAP_BLOCK_SIZE_EXP_MAX  (6)
 #endif
 
+/**
+ * @brief CoAP block-wise-transfer size that should be used by default
+ */
+#ifndef CONFIG_NANOCOAP_BLOCKSIZE_DEFAULT
+#define CONFIG_NANOCOAP_BLOCKSIZE_DEFAULT  COAP_BLOCKSIZE_64
+#endif
+
 /** @brief   Maximum length of a query string written to a message */
 #ifndef CONFIG_NANOCOAP_QS_MAX
 #define CONFIG_NANOCOAP_QS_MAX             (64)

sys/include/net/nanocoap_vfs.h

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2022 ML!PA Consulting GmbH
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     net_nanosock
+ * @brief       VFS NanoCoAP helper functions
+ *
+ * @{
+ *
+ * @file
+ * @brief       VFS NanoCoAP helper functions
+ *
+ * @author      Benjamin Valentin <[email protected]>
+ */
+#ifndef NET_NANOCOAP_VFS_H
+#define NET_NANOCOAP_VFS_H
+
+#include "net/nanocoap_sock.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Downloads the resource behind @p url via blockwise
+ *          GET and stores it in the file @p dst.
+ *
+ * @param[in]   url     URL to the resource
+ * @param[in]   dst     Path to the destination file
+ *
+ * @returns     0 on success
+ * @returns     <0 on error
+ */
+int nanocoap_vfs_get_url(const char *url, const char *dst);
+
+/**
+ * @brief   Downloads the resource behind @p path via blockwise
+ *          GET and stores it in the file @p dst.
+ *
+ * @param[in]   sock    Connection to the server
+ * @param[in]   path    Remote query path to the resource
+ * @param[in]   dst     Local path to the destination file
+ *
+ * @returns     0 on success
+ * @returns     <0 on error
+ */
+int nanocoap_vfs_get(nanocoap_sock_t *sock, const char *path, const char *dst);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* NET_NANOCOAP_VFS_H */
+/** @} */

sys/include/suit/transport/coap.h

@@ -76,7 +76,7 @@ extern const coap_resource_subtree_t coap_resource_subtree_suit;
  * @brief Coap block-wise-transfer size used for SUIT
  */
 #ifndef CONFIG_SUIT_COAP_BLOCKSIZE
-#define CONFIG_SUIT_COAP_BLOCKSIZE  COAP_BLOCKSIZE_64
+#define CONFIG_SUIT_COAP_BLOCKSIZE  CONFIG_NANOCOAP_BLOCKSIZE_DEFAULT
 #endif
 
 /**

sys/net/application_layer/nanocoap/vfs.c

@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2022 ML!PA Consulting GmbH
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     net_nanocoap
+ * @{
+ *
+ * @file
+ * @brief       Nanocoap VFS helpers
+ *
+ * @author      Benjamin Valentin <[email protected]>
+ *
+ * @}
+ */
+
+#include <fcntl.h>
+#include "net/nanocoap_sock.h"
+#include "net/sock/util.h"
+#include "vfs.h"
+
+#define ENABLE_DEBUG 0
+#include "debug.h"
+
+static int _2file(void *arg, size_t offset, uint8_t *buf, size_t len, int more)
+{
+    (void)more;
+    int *fd = arg;
+
+    vfs_lseek(*fd, offset, SEEK_SET);
+    return vfs_write(*fd, buf, len);
+}
+
+static int _prepare_file(const char *dst, char *dst_tmp, size_t len)
+{
+    /* download to temp file, rename it later */
+    if (snprintf(dst_tmp, len, "%s.t", dst) > (int)len) {
+        return -ENOBUFS;
+    }
+
+    return vfs_open(dst_tmp, O_CREAT | O_WRONLY | O_TRUNC, 0644);
+}
+
+static int _finalize_file(int fd, int res, const char *dst, const char *dst_tmp)
+{
+    vfs_close(fd);
+
+    /* move file to it's final location */
+    if (res >= 0) {
+        DEBUG("nanocoap: moving %s to %s\n", dst_tmp, dst);
+        vfs_unlink(dst);
+        res = vfs_rename(dst_tmp, dst);
+    }
+
+    vfs_unlink(dst_tmp);
+
+    return res;
+}
+
+int nanocoap_vfs_get(nanocoap_sock_t *sock, const char *path, const char *dst)
+{
+    int fd, res;
+    char dst_tmp[CONFIG_SOCK_URLPATH_MAXLEN];
+
+    DEBUG("nanocoap: downloading %s to %s\n", path, dst_tmp);
+
+    fd = _prepare_file(dst, dst_tmp, sizeof(dst_tmp));
+    if (fd < 0) {
+        return fd;
+    }
+    res = nanocoap_sock_get_blockwise(sock, path, CONFIG_NANOCOAP_BLOCKSIZE_DEFAULT,
+                                      _2file, &fd);
+    return _finalize_file(fd, res, dst, dst_tmp);
+}
+
+int nanocoap_vfs_get_url(const char *url, const char *dst)
+{
+    int fd, res;
+    char dst_tmp[CONFIG_SOCK_URLPATH_MAXLEN];
+
+    DEBUG("nanocoap: downloading %s to %s\n", url, dst_tmp);
+
+    fd = _prepare_file(dst, dst_tmp, sizeof(dst_tmp));
+    if (fd < 0) {
+        return fd;
+    }
+    res = nanocoap_get_blockwise_url(url, CONFIG_NANOCOAP_BLOCKSIZE_DEFAULT,
+                                     _2file, &fd);
+    return _finalize_file(fd, res, dst, dst_tmp);
+}

sys/shell/commands/Makefile

@@ -122,6 +122,10 @@ ifneq (,$(filter semtech-loramac,$(USEPKG)))
   SRC += sc_loramac.c
 endif
 
+ifneq (,$(filter nanocoap_vfs,$(USEMODULE)))
+  SRC += sc_nanocoap_vfs.c
+endif
+
 ifneq (,$(filter nimble_netif,$(USEMODULE)))
   SRC += sc_nimble_netif.c
 endif

sys/shell/commands/sc_nanocoap_vfs.c

@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2022 ML!PA Consulting GmbH
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     sys_shell_commands
+ * @{
+ *
+ * @file
+ * @brief       NanoCoAP commands that interact with the filesystem
+ *
+ * @author      Benjamin Valentin <[email protected]>
+ *
+ * @}
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+
+#include "vfs_default.h"
+#include "net/nanocoap_vfs.h"
+#include "net/nanocoap_sock.h"
+
+struct dir_list_ctx {
+    char *buf;
+    char *cur;
+    char *end;
+};
+
+static bool _is_dir(const char *url)
+{
+    int len = strlen(url);
+    return url[len - 1] == '/';
+}
+
+static int _print_cb(void *arg, size_t offset, uint8_t *buf, size_t len, int more)
+{
+    (void)arg;
+    (void)offset;
+
+    write(STDOUT_FILENO, buf, len);
+    if (!more) {
+        puts("");
+    }
+
+    return 0;
+}
+
+static int _print_dir_cb(void *arg, size_t offset, uint8_t *buf, size_t len, int more)
+{
+    (void)offset;
+    (void)more;
+
+    struct dir_list_ctx *ctx = arg;
+
+    char *end = (char *)buf + len;
+    for (char *c = (char *)buf; c < end; ++c) {
+        if (ctx->cur) {
+            if (*c == '>' || ctx->cur == ctx->end) {
+                *ctx->cur = 0;
+                puts(ctx->buf);
+                ctx->cur = NULL;
+            } else {
+                *ctx->cur++ = *c;
+            }
+        } else if (*c == '<') {
+            ctx->cur = ctx->buf;
+        }
+    }
+
+    return 0;
+}
+
+static int _print_dir(const char *url, char *buf, size_t len)
+{
+    struct dir_list_ctx ctx = {
+        .buf = buf,
+        .end = buf + len,
+    };
+    return nanocoap_get_blockwise_url(url, CONFIG_NANOCOAP_BLOCKSIZE_DEFAULT,
+                                      _print_dir_cb, &ctx);
+}
+
+int _nanocoap_get_handler(int argc, char **argv)
+{
+    int res;
+    char buffer[CONFIG_NANOCOAP_QS_MAX];
+    char *dst, *url = argv[1];
+
+    if (argc < 2) {
+        printf("Usage: %s <url> [destination]\n", argv[0]);
+        printf("Default destination: %s\n", VFS_DEFAULT_DATA);
+        return -EINVAL;
+    }
+
+    if (_is_dir(url) && argc < 3) {
+        res = _print_dir(url, buffer, sizeof(buffer));
+        if (res) {
+            printf("Request failed: %s\n", strerror(-res));
+        }
+        return res;
+    }
+
+    if (argc < 3) {
+        dst = strrchr(url, '/');
+        if (dst == NULL) {
+            printf("invalid url: '%s'\n", url);
+            return -EINVAL;
+        }
+        if (snprintf(buffer, sizeof(buffer), "%s%s",
+                     VFS_DEFAULT_DATA, dst) >= (int)sizeof(buffer)) {
+            printf("Output file path too long\n");
+            return -ENOBUFS;
+        }
+        dst = buffer;
+    } else {
+        dst = argv[2];
+    }
+
+    /* alternatively write the file to stdout */
+    if (strcmp(dst, "-") == 0) {
+        return nanocoap_get_blockwise_url(url, CONFIG_NANOCOAP_BLOCKSIZE_DEFAULT,
+                                          _print_cb, NULL);
+    }
+
+    res = nanocoap_vfs_get_url(url, dst);
+    if (res < 0) {
+        printf("Download failed: %s\n", strerror(-res));
+    } else {
+        printf("Saved as %s\n", dst);
+    }
+    return res;
+}

sys/shell/commands/shell_commands.c

@@ -187,6 +187,10 @@ extern int _i2c_scan(int argc, char **argv);
 extern int _loramac_handler(int argc, char **argv);
 #endif
 
+#ifdef MODULE_NANOCOAP_VFS
+extern int _nanocoap_get_handler(int argc, char **argv);
+#endif
+
 #ifdef MODULE_NICE
 extern int _sc_nice(int argc, char **argv);
 #endif
@@ -289,6 +293,9 @@ const shell_command_t _shell_command_list[] = {
 #ifdef MODULE_SHA256SUM
     {"sha256sum", "Compute and check SHA256 message digest", _vfs_sha256sum_cmd},
 #endif
+#ifdef MODULE_NANOCOAP_VFS
+    {"ncget", "download a file from a CoAP server", _nanocoap_get_handler},
+#endif
 #ifdef MODULE_GNRC_IPV6_NIB
     {"nib", "Configure neighbor information base", _gnrc_ipv6_nib},
 #endif

tests/nanocoap_cli/Makefile

@@ -15,6 +15,24 @@ USEMODULE += gnrc_ipv6_default
 
 USEMODULE += nanocoap_sock
 
+# boards where basic nanocoap functionality fits, but no VFS
+LOW_MEMORY_BOARDS := atmega1284p atxmega-a3bu-xplained derfmega128 \
+                     saml11-xpro bluepill saml10-xpro blackpill nucleo-f302r8 \
+                     stm32mp157c-dk2 stm32f7508-dk
+
+# Don't enable VFS functions on small boards
+ifeq (,$(filter $(BOARD),$(LOW_MEMORY_BOARDS)))
+  USEMODULE += nanocoap_vfs
+  USEMODULE += vfs_default
+  # USEMODULE += vfs_auto_format
+  USEMODULE += shell_commands
+
+  # always enable auto-format for native
+  ifeq ($(BOARD),native)
+    USEMODULE += vfs_auto_format
+  endif
+endif
+
 # Required by test
 USEMODULE += od
 USEMODULE += shell