From: Tomas Bzatek <tbzatek@redhat.com>
Date: Wed, 17 Apr 2024 16:04:34 +0000 (+0200)
Subject: fabrics: Introduce simple URI parser
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b67a5434f75a7df5c7180dfb15c8f7b5792aa295;p=users%2Fsagi%2Flibnvme.git

fabrics: Introduce simple URI parser

A very simple URI parser implementing URI syntax described
in the Boot Specification, rev. 1.0.

Signed-off-by: Tomas Bzatek <tbzatek@redhat.com>
---

diff --git a/src/libnvme.map b/src/libnvme.map
index b610a8ff..748c4f7a 100644
--- a/src/libnvme.map
+++ b/src/libnvme.map
@@ -2,6 +2,8 @@
 LIBNVME_1.10 {
 	global:
 		nvme_init_default_logging;
+		nvme_parse_uri;
+		nvme_free_uri;
 };
 
 LIBNVME_1.9 {
diff --git a/src/nvme/fabrics.c b/src/nvme/fabrics.c
index 6738e9dc..324a7321 100644
--- a/src/nvme/fabrics.c
+++ b/src/nvme/fabrics.c
@@ -1703,3 +1703,119 @@ int nvmf_register_ctrl(nvme_ctrl_t c, enum nvmf_dim_tas tas, __u32 *result)
 	 */
 	return nvmf_dim(c, tas, NVMF_TRTYPE_TCP, nvme_get_adrfam(c), "", NULL, result);
 }
+
+struct nvme_fabrics_uri *nvme_parse_uri(const char *str)
+{
+	struct nvme_fabrics_uri *uri;
+	_cleanup_free_ char *scheme = NULL;
+	_cleanup_free_ char *authority = NULL;
+	_cleanup_free_ char *path = NULL;
+	const char *host;
+	int i;
+
+	/* As defined in Boot Specification rev. 1.0:
+	 *
+	 * section 1.5.7: NVMe-oF URI Format
+	 *  nvme+tcp://192.168.1.1:4420/
+	 *  nvme+tcp://[FE80::1010]:4420/
+	 *
+	 * section 3.1.2.5.3: DHCP Root-Path - a hierarchical NVMe-oF URI Format
+	 *  NVME<+PROTOCOL>://<SERVERNAME/IP>[:TRANSPORT PORT]/<SUBSYS NQN>/<NID>
+	 * or
+	 *  NVME<+PROTOCOL>://<DISCOVERY CONTROLLER ADDRESS>[:DISCOVERY-
+	 *  -CONTROLLER PORT]/NQN.2014-08.ORG.NVMEXPRESS.DISCOVERY/<NID>
+	 */
+
+	/* TODO: unescape? */
+
+	uri = calloc(1, sizeof(struct nvme_fabrics_uri));
+	if (!uri)
+		return NULL;
+
+	if (sscanf(str, "%m[^:/]://%m[^/?#]%ms",
+		   &scheme, &authority, &path) < 2) {
+		nvme_free_uri(uri);
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (sscanf(scheme, "%m[^+]+%ms",
+		   &uri->scheme, &uri->protocol) < 1) {
+		nvme_free_uri(uri);
+		errno = EINVAL;
+		return NULL;
+	}
+
+	/* split userinfo */
+	host = strrchr(authority, '@');
+	if (host) {
+		host++;
+		uri->userinfo = strndup(authority, host - authority);
+	} else
+		host = authority;
+
+	/* try matching IPv6 address first */
+	if (sscanf(host, "[%m[^]]]:%d",
+		   &uri->host, &uri->port) < 1)
+		/* treat it as IPv4/hostname */
+		if (sscanf(host, "%m[^:]:%d",
+			   &uri->host, &uri->port) < 1) {
+			nvme_free_uri(uri);
+			errno = EINVAL;
+			return NULL;
+		}
+
+	/* split path into elements */
+	if (path) {
+		char *e, *elem;
+
+		/* separate the fragment */
+		e = strrchr(path, '#');
+		if (e) {
+			uri->fragment = strdup(e + 1);
+			*e = '\0';
+		}
+		/* separate the query string */
+		e = strrchr(path, '?');
+		if (e) {
+			uri->query = strdup(e + 1);
+			*e = '\0';
+		}
+
+		/* count elements first */
+		for (i = 0, e = path; *e; e++)
+			if (*e == '/' && *(e + 1) != '/')
+				i++;
+		uri->path_segments = calloc(i + 2, sizeof(char *));
+
+		i = 0;
+		elem = strtok_r(path, "/", &e);
+		if (elem)
+			uri->path_segments[i++] = strdup(elem);
+		while (elem && strlen(elem)) {
+			elem = strtok_r(NULL, "/", &e);
+			if (elem)
+				uri->path_segments[i++] = strdup(elem);
+		}
+	}
+
+	return uri;
+}
+
+void nvme_free_uri(struct nvme_fabrics_uri *uri)
+{
+	char **s;
+
+	if (!uri)
+		return;
+	free(uri->scheme);
+	free(uri->protocol);
+	free(uri->userinfo);
+	free(uri->host);
+	for (s = uri->path_segments; s && *s; s++)
+		free(*s);
+	free(uri->path_segments);
+	free(uri->query);
+	free(uri->fragment);
+	free(uri);
+}
diff --git a/src/nvme/fabrics.h b/src/nvme/fabrics.h
index 4ebeb35e..3be35310 100644
--- a/src/nvme/fabrics.h
+++ b/src/nvme/fabrics.h
@@ -67,6 +67,28 @@ struct nvme_fabrics_config {
 	bool concat;
 };
 
+/**
+ * struct nvme_fabrics_uri - Parsed URI structure
+ * @scheme:		Scheme name (typically 'nvme')
+ * @protocol:		Optional protocol/transport (e.g. 'tcp')
+ * @userinfo:		Optional user information component of the URI authority
+ * @host:		Host transport address
+ * @port:		The port subcomponent or 0 if not specified
+ * @path_segments:	NULL-terminated array of path segments
+ * @query:		Optional query string component (separated by '?')
+ * @fragment:		Optional fragment identifier component (separated by '#')
+ */
+struct nvme_fabrics_uri {
+	char *scheme;
+	char *protocol;
+	char *userinfo;
+	char *host;
+	int port;
+	char **path_segments;
+	char *query;
+	char *fragment;
+};
+
 /**
  * nvmf_trtype_str() - Decode TRTYPE field
  * @trtype: value to be decoded
@@ -324,4 +346,26 @@ bool nvmf_is_registration_supported(nvme_ctrl_t c);
  */
 int nvmf_register_ctrl(nvme_ctrl_t c, enum nvmf_dim_tas tas, __u32 *result);
 
+/**
+ * nvme_parse_uri() - Parse the URI string
+ * @str:	URI string
+ *
+ * Parse the URI string as defined in the NVM Express Boot Specification.
+ * Supported URI elements looks as follows:
+ *
+ *   nvme+tcp://user@host:port/subsys_nqn/nid?query=val#fragment
+ *
+ * Return: &nvme_fabrics_uri structure on success; NULL on failure with errno
+ * set.
+ */
+struct nvme_fabrics_uri *nvme_parse_uri(const char *str);
+
+/**
+ * nvme_free_uri() - Free the URI structure
+ * @uri:	&nvme_fabrics_uri structure
+ *
+ * Free an &nvme_fabrics_uri structure.
+ */
+void nvme_free_uri(struct nvme_fabrics_uri *uri);
+
 #endif /* _LIBNVME_FABRICS_H */