session client UPDATE support custom capabilities

Author: michalvasko

src/log_p.h

@@ -67,6 +67,7 @@ extern ATOMIC_T verbose_level;
 #define NC_CHECK_SRV_INIT_RET(RET) if (!ATOMIC_LOAD_RELAXED(server_opts.new_session_id)) {ERRINITSRV; return (RET);}
 #define NC_CHECK_ERRMEM_RET(COND, RET) if ((COND)) {ERRMEM; return (RET);}
 #define NC_CHECK_ERRMEM_GOTO(COND, RET, GOTO) if ((COND)) {ERRMEM; RET; goto GOTO;}
+#define NC_CHECK_GOTO(COND, GOTO) if ((COND)) {goto GOTO;}
 
 #define GETMACRO1(_1, NAME, ...) NAME
 #define GETMACRO2(_1, _2, NAME, ...) NAME

src/session.c

@@ -1079,41 +1079,49 @@ nc_session_free(struct nc_session *session, void (*data_free)(void *))
     free(session);
 }
 
-static void
-add_cpblt(const char *capab, char ***cpblts, int *size, int *count)
+/**
+ * @brief Add a capability into an array.
+ *
+ * @param[in] capab Capability to add.
+ * @param[in,out] cpblts Array of capabilities to add to, terminated with NULL.
+ * @param[in,out] count Count of @p cpblts.
+ * @return 0 on success;
+ * @return -1 on error.
+ */
+static int
+nc_add_cpblt(const char *capab, char ***cpblts, uint32_t *count)
 {
-    size_t len;
-    int i;
+    uint32_t i, len;
     char *p;
 
-    if (capab) {
-        /*  check if already present */
-        p = strchr(capab, '?');
-        if (p) {
-            len = p - capab;
-        } else {
-            len = strlen(capab);
-        }
-        for (i = 0; i < *count; i++) {
-            if (!strncmp((*cpblts)[i], capab, len) && (((*cpblts)[i][len] == '\0') || ((*cpblts)[i][len] == '?'))) {
-                /* already present, do not duplicate it */
-                return;
-            }
+    /*  check if already present */
+    p = strchr(capab, '?');
+    if (p) {
+        len = p - capab;
+    } else {
+        len = strlen(capab);
+    }
+    for (i = 0; i < *count; i++) {
+        if (!strncmp((*cpblts)[i], capab, len) && (((*cpblts)[i][len] == '\0') || ((*cpblts)[i][len] == '?'))) {
+            /* already present, do not duplicate it */
+            return 0;
         }
     }
 
     /* add another capability */
-    if (*count == *size) {
-        *size += 5;
-        *cpblts = nc_realloc(*cpblts, *size * sizeof **cpblts);
-        if (!(*cpblts)) {
-            ERRMEM;
-            return;
-        }
+    *cpblts = nc_realloc(*cpblts, (*count + 2) * sizeof **cpblts);
+    if (!(*cpblts)) {
+        ERRMEM;
+        return -1;
     }
 
-    (*cpblts)[*count] = capab ? strdup(capab) : NULL;
+    (*cpblts)[*count] = strdup(capab);
     ++(*count);
+
+    /* terminating NULL */
+    (*cpblts)[*count] = NULL;
+
+    return 0;
 }
 
 /**
@@ -1122,63 +1130,63 @@ add_cpblt(const char *capab, char ***cpblts, int *size, int *count)
  * @param[in] ctx libyang context.
  * @param[in] version YANG version of the schemas to be included in result.
  * @param[in] config_locked Whether the configuration lock is already held or should be acquired.
- * @return Array of capabilities, NULL on error.
+ * @return Array of capabilities terminated with NULL, NULL on error.
  */
 static char **
 _nc_server_get_cpblts_version(const struct ly_ctx *ctx, LYS_VERSION version, int config_locked)
 {
     char **cpblts;
     const struct lys_module *mod;
     const char *feat;
-    int size = 10, count, features_count = 0, dev_count = 0, str_len, len;
-    uint32_t u;
+    int features_count = 0, dev_count = 0, str_len, len;
+    uint32_t i, count;
     LY_ARRAY_COUNT_TYPE v;
     char *yl_content_id;
-    uint32_t wd_also_supported;
-    uint32_t wd_basic_mode;
+    uint32_t wd_also_supported, wd_basic_mode;
 
 #define NC_CPBLT_BUF_LEN 4096
     char str[NC_CPBLT_BUF_LEN];
 
     NC_CHECK_ARG_RET(NULL, ctx, NULL);
 
-    cpblts = malloc(size * sizeof *cpblts);
+    cpblts = malloc(3 * sizeof *cpblts);
     NC_CHECK_ERRMEM_GOTO(!cpblts, , error);
     cpblts[0] = strdup("urn:ietf:params:netconf:base:1.0");
     cpblts[1] = strdup("urn:ietf:params:netconf:base:1.1");
+    cpblts[2] = NULL;
     count = 2;
 
     mod = ly_ctx_get_module_implemented(ctx, "ietf-netconf");
     if (mod) {
         if (lys_feature_value(mod, "writable-running") == LY_SUCCESS) {
-            add_cpblt("urn:ietf:params:netconf:capability:writable-running:1.0", &cpblts, &size, &count);
+            NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:writable-running:1.0", &cpblts, &count), error);
         }
         if (lys_feature_value(mod, "candidate") == LY_SUCCESS) {
-            add_cpblt("urn:ietf:params:netconf:capability:candidate:1.0", &cpblts, &size, &count);
+            NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:candidate:1.0", &cpblts, &count), error);
             if (lys_feature_value(mod, "confirmed-commit") == LY_SUCCESS) {
-                add_cpblt("urn:ietf:params:netconf:capability:confirmed-commit:1.1", &cpblts, &size, &count);
+                NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:confirmed-commit:1.1", &cpblts, &count), error);
             }
         }
         if (lys_feature_value(mod, "rollback-on-error") == LY_SUCCESS) {
-            add_cpblt("urn:ietf:params:netconf:capability:rollback-on-error:1.0", &cpblts, &size, &count);
+            NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:rollback-on-error:1.0", &cpblts, &count), error);
         }
         if (lys_feature_value(mod, "validate") == LY_SUCCESS) {
-            add_cpblt("urn:ietf:params:netconf:capability:validate:1.1", &cpblts, &size, &count);
+            NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:validate:1.1", &cpblts, &count), error);
         }
         if (lys_feature_value(mod, "startup") == LY_SUCCESS) {
-            add_cpblt("urn:ietf:params:netconf:capability:startup:1.0", &cpblts, &size, &count);
+            NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:startup:1.0", &cpblts, &count), error);
         }
 
         /* The URL capability must be set manually using nc_server_set_capability()
          * because of the need for supported protocols to be included.
          * https://tools.ietf.org/html/rfc6241#section-8.8.3
          */
         // if (lys_feature_value(mod, "url") == LY_SUCCESS) {
-        // add_cpblt("urn:ietf:params:netconf:capability:url:1.0", &cpblts, &size, &count);
+        // NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:url:1.0", &cpblts, &count), error);
         // }
 
         if (lys_feature_value(mod, "xpath") == LY_SUCCESS) {
-            add_cpblt("urn:ietf:params:netconf:capability:xpath:1.0", &cpblts, &size, &count);
+            NC_CHECK_GOTO(nc_add_cpblt("urn:ietf:params:netconf:capability:xpath:1.0", &cpblts, &count), error);
         }
     }
 
@@ -1227,19 +1235,19 @@ _nc_server_get_cpblts_version(const struct ly_ctx *ctx, LYS_VERSION version, int
                 }
                 str[strlen(str) - 1] = '\0';
 
-                add_cpblt(str, &cpblts, &size, &count);
+                NC_CHECK_GOTO(nc_add_cpblt(str, &cpblts, &count), error);
             }
         }
     }
 
     /* other capabilities */
-    for (u = 0; u < server_opts.capabilities_count; u++) {
-        add_cpblt(server_opts.capabilities[u], &cpblts, &size, &count);
+    for (i = 0; i < server_opts.capabilities_count; i++) {
+        NC_CHECK_GOTO(nc_add_cpblt(server_opts.capabilities[i], &cpblts, &count), error);
     }
 
     /* models */
-    u = 0;
-    while ((mod = ly_ctx_get_module_iter(ctx, &u))) {
+    i = 0;
+    while ((mod = ly_ctx_get_module_iter(ctx, &i))) {
         if (nc_server_is_mod_ignored(mod->name, config_locked)) {
             /* ignored, not part of the cababilities */
             continue;
@@ -1265,12 +1273,12 @@ _nc_server_get_cpblts_version(const struct ly_ctx *ctx, LYS_VERSION version, int
                 /* new one (capab defined in RFC 8526 section 2) */
                 sprintf(str, "urn:ietf:params:netconf:capability:yang-library:1.1?revision=%s&content-id=%s",
                         mod->revision, yl_content_id);
-                add_cpblt(str, &cpblts, &size, &count);
+                NC_CHECK_GOTO(nc_add_cpblt(str, &cpblts, &count), error);
             } else {
                 /* old one (capab defined in RFC 7950 section 5.6.4) */
                 sprintf(str, "urn:ietf:params:netconf:capability:yang-library:1.0?revision=%s&module-set-id=%s",
                         mod->revision, yl_content_id);
-                add_cpblt(str, &cpblts, &size, &count);
+                NC_CHECK_GOTO(nc_add_cpblt(str, &cpblts, &count), error);
             }
             free(yl_content_id);
             continue;
@@ -1325,23 +1333,25 @@ _nc_server_get_cpblts_version(const struct ly_ctx *ctx, LYS_VERSION version, int
             }
         }
 
-        add_cpblt(str, &cpblts, &size, &count);
+        NC_CHECK_GOTO(nc_add_cpblt(str, &cpblts, &count), error);
     }
 
     /* HELLO UNLOCK */
     nc_rwlock_unlock(&server_opts.hello_lock, __func__);
 
-    /* ending NULL capability */
-    add_cpblt(NULL, &cpblts, &size, &count);
-
     return cpblts;
 
 unlock_error:
     /* HELLO UNLOCK */
     nc_rwlock_unlock(&server_opts.hello_lock, __func__);
 
 error:
-    free(cpblts);
+    if (cpblts) {
+        for (i = 0; cpblts[i]; ++i) {
+            free(cpblts[i]);
+        }
+        free(cpblts);
+    }
     return NULL;
 }
 
@@ -1414,6 +1424,44 @@ parse_cpblts(struct lyd_node *capabilities, char ***list)
     return ver;
 }
 
+/**
+ * @brief Get client-side capabilities.
+ *
+ * @return Array of capabilities terminated with NULL, NULL on error.
+ */
+static char **
+nc_client_get_cpblts(void)
+{
+    char **cpblts = NULL;
+    uint32_t i, count;
+
+    cpblts = malloc(3 * sizeof *cpblts);
+    NC_CHECK_ERRMEM_GOTO(!cpblts, , error);
+
+    cpblts[0] = strdup("urn:ietf:params:netconf:base:1.0");
+    NC_CHECK_ERRMEM_GOTO(!cpblts[0], , error);
+    cpblts[1] = strdup("urn:ietf:params:netconf:base:1.1");
+    NC_CHECK_ERRMEM_GOTO(!cpblts[1], , error);
+    cpblts[2] = NULL;
+    count = 3;
+
+    /* custom capabilities */
+    for (i = 0; i < client_opts.capabilities_count; ++i) {
+        NC_CHECK_GOTO(nc_add_cpblt(client_opts.capabilities[i], &cpblts, &count), error);
+    }
+
+    return cpblts;
+
+error:
+    if (cpblts) {
+        for (i = 0; cpblts[i]; ++i) {
+            free(cpblts[i]);
+        }
+        free(cpblts);
+    }
+    return NULL;
+}
+
 /**
  * @brief Send NETCONF hello message on a session.
  *
@@ -1431,11 +1479,10 @@ nc_send_hello_io(struct nc_session *session, int config_locked)
 
     if (session->side == NC_CLIENT) {
         /* client side hello - send only NETCONF base capabilities */
-        cpblts = malloc(3 * sizeof *cpblts);
-        NC_CHECK_ERRMEM_RET(!cpblts, NC_MSG_ERROR);
-        cpblts[0] = strdup("urn:ietf:params:netconf:base:1.0");
-        cpblts[1] = strdup("urn:ietf:params:netconf:base:1.1");
-        cpblts[2] = NULL;
+        cpblts = nc_client_get_cpblts();
+        if (!cpblts) {
+            return NC_MSG_ERROR;
+        }
 
         timeout_io = NC_CLIENT_HELLO_TIMEOUT * 1000;
         sid = NULL;

src/session_client.c

@@ -4,7 +4,7 @@
  * @brief libnetconf2 session client functions
  *
  * @copyright
- * Copyright (c) 2015 - 2021 CESNET, z.s.p.o.
+ * Copyright (c) 2015 - 2026 CESNET, z.s.p.o.
  *
  * This source code is licensed under BSD 3-Clause License (the "License").
  * You may not use this file except in compliance with the License.
@@ -99,6 +99,7 @@ static void
 nc_client_context_free(void *ptr)
 {
     struct nc_client_context *c = (struct nc_client_context *)ptr;
+    uint32_t i;
 
     if (--(c->refcount)) {
         /* still used */
@@ -115,11 +116,13 @@ nc_client_context_free(void *ptr)
     {
         /* for the main thread the same is done in nc_client_destroy() */
         free(c->opts.schema_searchpath);
+        for (i = 0; i < c->opts.capabilities_count; i++) {
+            free(c->opts.capabilities[i]);
+        }
+        free(c->opts.capabilities);
         free(c->unix_opts.username);
 
 #ifdef NC_ENABLED_SSH_TLS
-        int i;
-
         for (i = 0; i < c->opts.ch_bind_count; ++i) {
             close(c->opts.ch_binds[i].sock);
             free((char *)c->opts.ch_binds[i].address);
@@ -204,9 +207,6 @@ nc_client_context_location(void)
     return e;
 }
 
-#define client_opts nc_client_context_location()->opts
-#define unix_opts nc_client_context_location()->unix_opts
-
 API void *
 nc_client_get_thread_context(void)
 {
@@ -325,12 +325,35 @@ nc_client_unix_set_username(const char *username)
         NC_CHECK_ERRMEM_RET(!new_user, -1);
     }
 
-    free(unix_opts.username);
-    unix_opts.username = new_user;
+    free(client_unix_opts.username);
+    client_unix_opts.username = new_user;
 
     return 0;
 }
 
+API int
+nc_client_set_capability(const char *value)
+{
+    int rc = 0;
+    void *mem;
+
+    if (!value || !value[0]) {
+        ERRARG(NULL, "value must not be empty");
+        return -1;
+    }
+
+    mem = realloc(client_opts.capabilities, (client_opts.capabilities_count + 1) * sizeof *client_opts.capabilities);
+    NC_CHECK_ERRMEM_GOTO(!mem, rc = -1, cleanup);
+    client_opts.capabilities = mem;
+
+    client_opts.capabilities[client_opts.capabilities_count] = strdup(value);
+    NC_CHECK_ERRMEM_GOTO(!client_opts.capabilities[client_opts.capabilities_count], rc = -1, cleanup);
+    client_opts.capabilities_count++;
+
+cleanup:
+    return rc;
+}
+
 struct module_info {
     char *name;
     char *revision;
@@ -1485,8 +1508,8 @@ nc_connect_unix(const char *address, struct ly_ctx *ctx)
     }
 
     /* NETCONF username */
-    if (unix_opts.username) {
-        username = strdup(unix_opts.username);
+    if (client_unix_opts.username) {
+        username = strdup(client_unix_opts.username);
     } else {
         pw = nc_getpw(geteuid(), NULL, &pw_buf, &buf, &buf_size);
         if (!pw) {