diff options
Diffstat (limited to 'zebra/zebra_srv6.c')
| -rw-r--r-- | zebra/zebra_srv6.c | 2071 |
1 files changed, 2036 insertions, 35 deletions
diff --git a/zebra/zebra_srv6.c b/zebra/zebra_srv6.c index bb872ef9..082d4609 100644 --- a/zebra/zebra_srv6.c +++ b/zebra/zebra_srv6.c @@ -18,11 +18,6 @@ #include "zebra/zebra_srv6.h" #include "zebra/zebra_errors.h" #include "zebra/ge_netlink.h" -#include <stdio.h> -#include <string.h> -#include <stdlib.h> -#include <arpa/inet.h> -#include <netinet/in.h> #include <stdio.h> #include <string.h> @@ -33,6 +28,16 @@ DEFINE_MGROUP(SRV6_MGR, "SRv6 Manager"); DEFINE_MTYPE_STATIC(SRV6_MGR, SRV6M_CHUNK, "SRv6 Manager Chunk"); +DEFINE_MTYPE_STATIC(SRV6_MGR, ZEBRA_SRV6_SID_BLOCK, "SRv6 SID block"); +DEFINE_MTYPE_STATIC(SRV6_MGR, ZEBRA_SRV6_SID_FUNC, "SRv6 SID function"); +DEFINE_MTYPE_STATIC(SRV6_MGR, ZEBRA_SRV6_USID_WLIB, + "SRv6 uSID Wide LIB information"); +DEFINE_MTYPE_STATIC(SRV6_MGR, ZEBRA_SRV6_SID, "SRv6 SID"); +DEFINE_MTYPE_STATIC(SRV6_MGR, ZEBRA_SRV6_SID_CTX, "SRv6 SID context"); + +/* Prototypes */ +static int release_srv6_sid_func_dynamic(struct zebra_srv6_sid_block *block, + uint32_t sid_func); /* define hooks for the basic API, so that it can be specialized or served * externally @@ -55,6 +60,18 @@ DEFINE_HOOK(srv6_manager_release_chunk, vrf_id_t vrf_id), (client, locator_name, vrf_id)); +DEFINE_HOOK(srv6_manager_get_sid, + (struct zebra_srv6_sid **sid, struct zserv *client, + struct srv6_sid_ctx *ctx, struct in6_addr *sid_value, + const char *locator_name), + (sid, client, ctx, sid_value, locator_name)); +DEFINE_HOOK(srv6_manager_release_sid, + (struct zserv *client, struct srv6_sid_ctx *ctx), (client, ctx)); +DEFINE_HOOK(srv6_manager_get_locator, + (struct srv6_locator **locator, struct zserv *client, + const char *locator_name), + (locator, client, locator_name)); + /* define wrappers to be called in zapi_msg.c (as hooks must be called in * source file where they were defined) */ @@ -85,11 +102,502 @@ int srv6_manager_client_disconnect_cb(struct zserv *client) return 0; } + +void srv6_manager_get_sid_call(struct zebra_srv6_sid **sid, + struct zserv *client, struct srv6_sid_ctx *ctx, + struct in6_addr *sid_value, + const char *locator_name) +{ + hook_call(srv6_manager_get_sid, sid, client, ctx, sid_value, + locator_name); +} + +void srv6_manager_release_sid_call(struct zserv *client, + struct srv6_sid_ctx *ctx) +{ + hook_call(srv6_manager_release_sid, client, ctx); +} + +void srv6_manager_get_locator_call(struct srv6_locator **locator, + struct zserv *client, + const char *locator_name) +{ + hook_call(srv6_manager_get_locator, locator, client, locator_name); +} + static int zebra_srv6_cleanup(struct zserv *client) { + /* Client has disconnected, let's release all the SIDs allocated by it. */ + release_daemon_srv6_sids(client); return 0; } +/* --- Zebra SRv6 SID context management functions -------------------------- */ + +struct zebra_srv6_sid_ctx *zebra_srv6_sid_ctx_alloc(void) +{ + struct zebra_srv6_sid_ctx *ctx = NULL; + + ctx = XCALLOC(MTYPE_ZEBRA_SRV6_SID_CTX, + sizeof(struct zebra_srv6_sid_ctx)); + + return ctx; +} + +void zebra_srv6_sid_ctx_free(struct zebra_srv6_sid_ctx *ctx) +{ + XFREE(MTYPE_ZEBRA_SRV6_SID_CTX, ctx); +} + +/** + * Free an SRv6 SID context. + * + * @param val SRv6 SID context to be freed + */ +void delete_zebra_srv6_sid_ctx(void *val) +{ + zebra_srv6_sid_ctx_free((struct zebra_srv6_sid_ctx *)val); +} + +/* --- Zebra SRv6 SID format management functions --------------------------- */ + +void srv6_sid_format_register(struct srv6_sid_format *format) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + + /* Ensure that the format is registered only once */ + assert(!srv6_sid_format_lookup(format->name)); + + listnode_add(srv6->sid_formats, format); +} + +void srv6_sid_format_unregister(struct srv6_sid_format *format) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + + listnode_delete(srv6->sid_formats, format); +} + +struct srv6_sid_format *srv6_sid_format_lookup(const char *name) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct srv6_sid_format *format; + struct listnode *node; + + for (ALL_LIST_ELEMENTS_RO(srv6->sid_formats, node, format)) + if (!strncmp(name, format->name, sizeof(format->name))) + return format; + + return NULL; +} + +/* + * Called to change the SID format of a locator. + * + * After switching the locator to a different format, the SIDs allocated + * from the locator may no longer be valid; we need to notify the + * interested zclient that the locator has changed, so that the + * zclients can withdraw/uninstall the old SIDs, allocate/advertise/program + * the new SIDs. + */ +void zebra_srv6_locator_format_set(struct srv6_locator *locator, + struct srv6_sid_format *format) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct zebra_srv6_sid_block *block_old, *block_new; + struct prefix_ipv6 block_pfx_new; + struct listnode *node, *nnode; + struct zebra_srv6_sid_ctx *ctx; + + if (!locator) + return; + + locator->sid_format = format; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: Locator %s format has changed, old=%s new=%s", + __func__, locator->name, + locator->sid_format ? ((struct srv6_sid_format *) + locator->sid_format) + ->name + : NULL, + format ? format->name : NULL); + + /* Notify zclients that the locator is no longer valid */ + zebra_notify_srv6_locator_delete(locator); + + for (ALL_LIST_ELEMENTS(srv6->sids, node, nnode, ctx)) { + if (!ctx->sid || ctx->sid->locator != locator) + continue; + + if (ctx->sid) + zebra_srv6_sid_free(ctx->sid); + + listnode_delete(srv6->sids, ctx); + zebra_srv6_sid_ctx_free(ctx); + } + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: Locator %s format has changed, send SRV6_LOCATOR_DEL notification to zclients", + __func__, locator->name); + + /* Release the current parent block */ + block_old = locator->sid_block; + if (block_old) { + block_old->refcnt--; + if (block_old->refcnt == 0) { + listnode_delete(srv6->sid_blocks, block_old); + zebra_srv6_sid_block_free(block_old); + } + } + locator->sid_block = NULL; + + block_pfx_new = locator->prefix; + if (format) + block_pfx_new.prefixlen = format->block_len; + else + block_pfx_new.prefixlen = locator->block_bits_length; + apply_mask(&block_pfx_new); + + /* Allocate the new parent block */ + block_new = zebra_srv6_sid_block_lookup(&block_pfx_new); + if (!block_new) { + block_new = zebra_srv6_sid_block_alloc(format, &block_pfx_new); + listnode_add(srv6->sid_blocks, block_new); + } + + block_new->refcnt++; + locator->sid_block = block_new; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: Locator %s format has changed, send SRV6_LOCATOR_ADD notification to zclients", + __func__, locator->name); + + /* Notify zclients about the updated locator */ + zebra_srv6_locator_add(locator); +} + +/* + * Called when a SID format is modified by the user. + * + * After modifying a SID format, the SIDs that are using that format may no + * longer be valid. + * This function walks through the list of locators that are using the SID format + * and notifies the zclients that the locator has changed, so that the zclients + * can withdraw/uninstall the old SIDs, allocate/program/advertise the new SIDs. + */ +void zebra_srv6_sid_format_changed_cb(struct srv6_sid_format *format) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct srv6_locator *locator; + struct listnode *node, *nnode; + struct zebra_srv6_sid_ctx *ctx; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: SID format %s has changed. Notifying zclients.", + __func__, format->name); + + for (ALL_LIST_ELEMENTS_RO(srv6->locators, node, locator)) { + if (locator->sid_format == format) { + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: Locator %s has changed because its format (%s) has been modified. Notifying zclients.", + __func__, locator->name, + format->name); + + /* Notify zclients that the locator is no longer valid */ + zebra_notify_srv6_locator_delete(locator); + + for (ALL_LIST_ELEMENTS(srv6->sids, node, nnode, ctx)) { + if (!ctx->sid || ctx->sid->locator != locator) + continue; + + if (ctx->sid) + zebra_srv6_sid_free(ctx->sid); + + listnode_delete(srv6->sids, ctx); + zebra_srv6_sid_ctx_free(ctx); + } + + /* Notify zclients about the updated locator */ + zebra_notify_srv6_locator_add(locator); + } + } +} + +/* + * Helper function to create the SRv6 compressed format `usid-f3216`. + */ +static struct srv6_sid_format *create_srv6_sid_format_usid_f3216(void) +{ + struct srv6_sid_format *format = NULL; + + format = srv6_sid_format_alloc(SRV6_SID_FORMAT_USID_F3216_NAME); + + format->type = SRV6_SID_FORMAT_TYPE_USID; + + /* Define block/node/function length */ + format->block_len = SRV6_SID_FORMAT_USID_F3216_BLOCK_LEN; + format->node_len = SRV6_SID_FORMAT_USID_F3216_NODE_LEN; + format->function_len = SRV6_SID_FORMAT_USID_F3216_FUNCTION_LEN; + format->argument_len = SRV6_SID_FORMAT_USID_F3216_ARGUMENT_LEN; + + /* Define the ranges from which the SID function can be allocated */ + format->config.usid.lib_start = SRV6_SID_FORMAT_USID_F3216_LIB_START; + format->config.usid.elib_start = SRV6_SID_FORMAT_USID_F3216_ELIB_START; + format->config.usid.elib_end = SRV6_SID_FORMAT_USID_F3216_ELIB_END; + format->config.usid.wlib_start = SRV6_SID_FORMAT_USID_F3216_WLIB_START; + format->config.usid.wlib_end = SRV6_SID_FORMAT_USID_F3216_WLIB_END; + format->config.usid.ewlib_start = SRV6_SID_FORMAT_USID_F3216_EWLIB_START; + + return format; +} + +/* + * Helper function to create the SRv6 uncompressed format. + */ +static struct srv6_sid_format *create_srv6_sid_format_uncompressed(void) +{ + struct srv6_sid_format *format = NULL; + + format = srv6_sid_format_alloc(SRV6_SID_FORMAT_UNCOMPRESSED_F4024_NAME); + + format->type = SRV6_SID_FORMAT_TYPE_UNCOMPRESSED; + + /* Define block/node/function length */ + format->block_len = SRV6_SID_FORMAT_UNCOMPRESSED_F4024_BLOCK_LEN; + format->node_len = SRV6_SID_FORMAT_UNCOMPRESSED_F4024_NODE_LEN; + format->function_len = SRV6_SID_FORMAT_UNCOMPRESSED_F4024_FUNCTION_LEN; + format->argument_len = SRV6_SID_FORMAT_UNCOMPRESSED_F4024_ARGUMENT_LEN; + + /* Define the ranges from which the SID function can be allocated */ + format->config.uncompressed.explicit_start = + SRV6_SID_FORMAT_UNCOMPRESSED_F4024_EXPLICIT_RANGE_START; + + return format; +} + +/* --- Zebra SRv6 SID function management functions ---------------------------- */ + +uint32_t *zebra_srv6_sid_func_alloc(uint32_t func) +{ + uint32_t *sid_func_ptr; + + sid_func_ptr = XCALLOC(MTYPE_ZEBRA_SRV6_SID_FUNC, sizeof(uint32_t)); + *sid_func_ptr = func; + + return sid_func_ptr; +} + +void zebra_srv6_sid_func_free(uint32_t *func) +{ + XFREE(MTYPE_ZEBRA_SRV6_SID_FUNC, func); +} + +/** + * Free an SRv6 SID function. + * + * @param val SRv6 SID function to be freed + */ +void delete_zebra_srv6_sid_func(void *val) +{ + zebra_srv6_sid_func_free((uint32_t *)val); +} + +/* --- Zebra SRv6 SID block management functions ---------------------------- */ + +static struct zebra_srv6_sid_block *zebra_srv6_sid_block_alloc_internal(void) +{ + struct zebra_srv6_sid_block *block = NULL; + + block = XCALLOC(MTYPE_ZEBRA_SRV6_SID_BLOCK, + sizeof(struct zebra_srv6_sid_block)); + + return block; +} + +struct zebra_srv6_sid_block * +zebra_srv6_sid_block_alloc(struct srv6_sid_format *format, + struct prefix_ipv6 *prefix) +{ + struct zebra_srv6_sid_block *block; + + block = zebra_srv6_sid_block_alloc_internal(); + block->sid_format = format; + block->prefix = *prefix; + + if (format) { + if (format->type == SRV6_SID_FORMAT_TYPE_USID) { + uint32_t wlib_start, wlib_end, func; + + /* Init uSID LIB */ + block->u.usid.lib.func_allocated = list_new(); + block->u.usid.lib.func_allocated->del = + delete_zebra_srv6_sid_func; + block->u.usid.lib.func_released = list_new(); + block->u.usid.lib.func_released->del = + delete_zebra_srv6_sid_func; + block->u.usid.lib.first_available_func = + format->config.usid.lib_start; + + /* Init uSID Wide LIB */ + wlib_start = block->sid_format->config.usid.wlib_start; + wlib_end = block->sid_format->config.usid.wlib_end; + block->u.usid.wide_lib = + XCALLOC(MTYPE_ZEBRA_SRV6_USID_WLIB, + (wlib_end - wlib_start + 1) * + sizeof(struct wide_lib)); + for (func = 0; func < wlib_end - wlib_start + 1; + func++) { + block->u.usid.wide_lib[func].func_allocated = + list_new(); + block->u.usid.wide_lib[func].func_allocated->del = + delete_zebra_srv6_sid_func; + block->u.usid.wide_lib[func].func_released = + list_new(); + block->u.usid.wide_lib[func].func_released->del = + delete_zebra_srv6_sid_func; + block->u.usid.wide_lib[func].func = func; + } + } else if (format->type == SRV6_SID_FORMAT_TYPE_UNCOMPRESSED) { + block->u.uncompressed.func_allocated = list_new(); + block->u.uncompressed.func_allocated->del = + delete_zebra_srv6_sid_func; + block->u.uncompressed.func_released = list_new(); + block->u.uncompressed.func_released->del = + delete_zebra_srv6_sid_func; + block->u.uncompressed.first_available_func = + SRV6_SID_FORMAT_UNCOMPRESSED_F4024_FUNC_UNRESERVED_MIN; + } else { + /* We should never arrive here */ + assert(0); + } + } else { + block->u.uncompressed.func_allocated = list_new(); + block->u.uncompressed.func_allocated->del = + delete_zebra_srv6_sid_func; + block->u.uncompressed.func_released = list_new(); + block->u.uncompressed.func_released->del = + delete_zebra_srv6_sid_func; + block->u.uncompressed.first_available_func = 1; + } + + return block; +} + +void zebra_srv6_sid_block_free(struct zebra_srv6_sid_block *block) +{ + if (block->sid_format) { + if (block->sid_format->type == SRV6_SID_FORMAT_TYPE_USID) { + uint32_t wlib_start, wlib_end, func; + + /* Free uSID LIB */ + list_delete(&block->u.usid.lib.func_allocated); + list_delete(&block->u.usid.lib.func_released); + + /* Free uSID Wide LIB */ + wlib_start = block->sid_format->config.usid.wlib_start; + wlib_end = block->sid_format->config.usid.wlib_end; + for (func = 0; func < wlib_end - wlib_start + 1; + func++) { + list_delete(&block->u.usid.wide_lib[func] + .func_allocated); + list_delete(&block->u.usid.wide_lib[func] + .func_released); + } + XFREE(MTYPE_ZEBRA_SRV6_USID_WLIB, + block->u.usid.wide_lib); + } else if (block->sid_format->type == + SRV6_SID_FORMAT_TYPE_UNCOMPRESSED) { + list_delete(&block->u.uncompressed.func_allocated); + list_delete(&block->u.uncompressed.func_released); + } else { + /* We should never arrive here */ + assert(0); + } + } else { + list_delete(&block->u.uncompressed.func_allocated); + list_delete(&block->u.uncompressed.func_released); + } + + XFREE(MTYPE_ZEBRA_SRV6_SID_BLOCK, block); +} + +/** + * Free an SRv6 SID block. + * + * @param val SRv6 SID block to be freed + */ +void delete_zebra_srv6_sid_block(void *val) +{ + zebra_srv6_sid_block_free((struct zebra_srv6_sid_block *)val); +} + +struct zebra_srv6_sid_block * +zebra_srv6_sid_block_lookup(struct prefix_ipv6 *prefix) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct zebra_srv6_sid_block *block; + struct listnode *node; + + for (ALL_LIST_ELEMENTS_RO(srv6->sid_blocks, node, block)) + if (prefix_match(prefix, &block->prefix)) + return block; + + return NULL; +} + +/* --- Zebra SRv6 SID management functions ---------------------------------- */ + +/** + * Alloc and fill an SRv6 SID. + * + * @param ctx Context associated with the SID to be created + * @param sid_value IPv6 address associated with the SID to be created + * @param locator Parent locator of the SID to be created + * @param sid_block Block from which the SID value has been allocated + * @param sid_func Function part of the SID to be created + * @param alloc_mode Allocation mode of the Function (dynamic vs explicit) + * @return The requested SID + */ +struct zebra_srv6_sid * +zebra_srv6_sid_alloc(struct zebra_srv6_sid_ctx *ctx, struct in6_addr *sid_value, + struct srv6_locator *locator, + struct zebra_srv6_sid_block *sid_block, uint32_t sid_func, + enum srv6_sid_alloc_mode alloc_mode) +{ + struct zebra_srv6_sid *sid; + + if (!ctx || !sid_value) + return NULL; + + sid = XCALLOC(MTYPE_ZEBRA_SRV6_SID, sizeof(struct zebra_srv6_sid)); + sid->ctx = ctx; + sid->value = *sid_value; + sid->locator = locator; + sid->block = sid_block; + sid->func = sid_func; + sid->alloc_mode = alloc_mode; + sid->client_list = list_new(); + + return sid; +} + +void zebra_srv6_sid_free(struct zebra_srv6_sid *sid) +{ + list_delete(&sid->client_list); + XFREE(MTYPE_ZEBRA_SRV6_SID, sid); +} + +/** + * Free an SRv6 SID. + * + * @param val SRv6 SID to be freed + */ +void delete_zebra_srv6_sid(void *val) +{ + zebra_srv6_sid_free((struct zebra_srv6_sid *)val); +} + void zebra_srv6_locator_add(struct srv6_locator *locator) { struct zebra_srv6 *srv6 = zebra_srv6_get_default(); @@ -121,7 +629,6 @@ void zebra_srv6_locator_add(struct srv6_locator *locator) void zebra_srv6_locator_delete(struct srv6_locator *locator) { struct listnode *n; - struct srv6_locator_chunk *c; struct zebra_srv6 *srv6 = zebra_srv6_get_default(); struct zserv *client; @@ -136,18 +643,8 @@ void zebra_srv6_locator_delete(struct srv6_locator *locator) * by ZEBRA_SRV6_LOCATOR_DELETE, and this notification is sent to the * owner of each chunk. */ - for (ALL_LIST_ELEMENTS_RO((struct list *)locator->chunks, n, c)) { - if (c->proto == ZEBRA_ROUTE_SYSTEM) - continue; - client = zserv_find_client(c->proto, c->instance); - if (!client) { - zlog_warn( - "%s: Not found zclient(proto=%u, instance=%u).", - __func__, c->proto, c->instance); - continue; - } + for (ALL_LIST_ELEMENTS_RO(zrouter.client_list, n, client)) zsend_zebra_srv6_locator_delete(client, locator); - } listnode_delete(srv6->locators, locator); srv6_locator_free(locator); @@ -190,7 +687,6 @@ void zebra_notify_srv6_locator_add(struct srv6_locator *locator) void zebra_notify_srv6_locator_delete(struct srv6_locator *locator) { struct listnode *n; - struct srv6_locator_chunk *c; struct zserv *client; /* @@ -204,17 +700,8 @@ void zebra_notify_srv6_locator_delete(struct srv6_locator *locator) * by ZEBRA_SRV6_LOCATOR_DELETE, and this notification is sent to the * owner of each chunk. */ - for (ALL_LIST_ELEMENTS_RO((struct list *)locator->chunks, n, c)) { - if (c->proto == ZEBRA_ROUTE_SYSTEM) - continue; - client = zserv_find_client(c->proto, c->instance); - if (!client) { - zlog_warn("Not found zclient(proto=%u, instance=%u).", - c->proto, c->instance); - continue; - } + for (ALL_LIST_ELEMENTS_RO(zrouter.client_list, n, client)) zsend_zebra_srv6_locator_delete(client, locator); - } } struct zebra_srv6 srv6; @@ -222,10 +709,32 @@ struct zebra_srv6 srv6; struct zebra_srv6 *zebra_srv6_get_default(void) { static bool first_execution = true; + struct srv6_sid_format *format_usidf3216; + struct srv6_sid_format *format_uncompressed; if (first_execution) { first_execution = false; srv6.locators = list_new(); + + /* Initialize list of SID formats */ + srv6.sid_formats = list_new(); + srv6.sid_formats->del = delete_srv6_sid_format; + + /* Create SID format `usid-f3216` */ + format_usidf3216 = create_srv6_sid_format_usid_f3216(); + srv6_sid_format_register(format_usidf3216); + + /* Create SID format `uncompressed` */ + format_uncompressed = create_srv6_sid_format_uncompressed(); + srv6_sid_format_register(format_uncompressed); + + /* Init list to store SRv6 SIDs */ + srv6.sids = list_new(); + srv6.sids->del = delete_zebra_srv6_sid_ctx; + + /* Init list to store SRv6 SID blocks */ + srv6.sid_blocks = list_new(); + srv6.sid_blocks->del = delete_zebra_srv6_sid_block; } return &srv6; } @@ -427,21 +936,1507 @@ void zebra_srv6_encap_src_addr_unset(void) memset(&srv6->encap_src_addr, 0, sizeof(struct in6_addr)); } +/* --- SRv6 SID Allocation/Release functions -------------------------------- */ + +/** + * Return the SRv6 SID obtained composing the locator and function. + * + * @param sid_value SRv6 SID address returned + * @param locator Parent locator of the SRv6 SID + * @param sid_func Function part of the SID + * @return True if success, False otherwise + */ +static bool zebra_srv6_sid_compose(struct in6_addr *sid_value, + struct srv6_locator *locator, + uint32_t sid_func) +{ + uint8_t offset, func_len; + struct srv6_sid_format *format; + + if (!sid_value || !locator) + return false; + + format = locator->sid_format; + if (format) { + offset = format->block_len + format->node_len; + func_len = format->function_len; + } else { + offset = locator->block_bits_length + locator->node_bits_length; + func_len = locator->function_bits_length; + } + + *sid_value = locator->prefix.prefix; + for (uint8_t idx = 0; idx < func_len; idx++) { + uint8_t tidx = offset + idx; + + sid_value->s6_addr[tidx / 8] &= ~(0x1 << (7 - tidx % 8)); + if (sid_func >> (func_len - 1 - idx) & 0x1) + sid_value->s6_addr[tidx / 8] |= 0x1 << (7 - tidx % 8); + } + + return true; +} + +/** + * Return the parent locator and function of an SRv6 SID. + * + * @param sid_value SRv6 SID address to be decomposed + * @param sid_block Parent block of the SRv6 SID + * @param locator Parent locator of the SRv6 SID + * @param sid_func Function part of the SID + * @param sid_wide_func Wide function of the SID + * @return True if success, False otherwise + */ +static bool zebra_srv6_sid_decompose(struct in6_addr *sid_value, + struct zebra_srv6_sid_block **sid_block, + struct srv6_locator **locator, + uint32_t *sid_func, uint32_t *sid_wide_func) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct srv6_locator *l; + struct zebra_srv6_sid_block *b; + struct srv6_sid_format *format; + struct listnode *node; + struct prefix_ipv6 tmp_prefix; + uint8_t offset, func_len; + + if (!sid_value || !sid_func) + return false; + + *sid_func = 0; + *sid_wide_func = 0; + + /* + * Build a temporary prefix_ipv6 object representing the SRv6 SID. + * This temporary prefix object is used below by the prefix_match + * function to check if the SID belongs to a specific locator. + */ + tmp_prefix.family = AF_INET6; + tmp_prefix.prefixlen = IPV6_MAX_BITLEN; + tmp_prefix.prefix = *sid_value; + + /* + * Lookup the parent locator of the SID and return the locator and + * the function of the SID. + */ + for (ALL_LIST_ELEMENTS_RO(srv6->locators, node, l)) { + /* + * Check if the locator prefix includes the temporary prefix + * representing the SID. + */ + if (prefix_match((struct prefix *)&l->prefix, + (struct prefix *)&tmp_prefix)) { + format = l->sid_format; + + if (format) { + offset = format->block_len + format->node_len; + func_len = format->function_len; + } else { + offset = l->block_bits_length + + l->node_bits_length; + func_len = l->function_bits_length; + } + + for (uint8_t idx = 0; idx < func_len; idx++) { + uint8_t tidx = offset + idx; + *sid_func |= (sid_value->s6_addr[tidx / 8] & + (0x1 << (7 - tidx % 8))) + << (((func_len - 1 - idx) / 8) * 8); + } + + /* + * If function comes from the Wide LIB range, we also + * need to get the Wide function. + */ + if (format && format->type == SRV6_SID_FORMAT_TYPE_USID) { + if (*sid_func >= format->config.usid.wlib_start && + *sid_func <= format->config.usid.wlib_end) { + format = l->sid_format; + + offset = format->block_len + + format->node_len + + format->function_len; + + for (uint8_t idx = 0; idx < 16; idx++) { + uint8_t tidx = offset + idx; + *sid_wide_func |= + (sid_value->s6_addr[tidx / + 8] & + (0x1 << (7 - tidx % 8))) + << (((16 - 1 - idx) / 8) * + 8); + } + } + } + + *locator = l; + *sid_block = l->sid_block; + + return true; + } + } + + /* + * If we arrive here, the SID does not belong to any locator. + * Then, let's try to find the parent block from which the SID + * has been allocated. + */ + + /* + * Lookup the parent block of the SID and return the block and + * the function of the SID. + */ + for (ALL_LIST_ELEMENTS_RO(srv6->sid_blocks, node, b)) { + /* + * Check if the block prefix includes the temporary prefix + * representing the SID + */ + if (prefix_match((struct prefix *)&b->prefix, + (struct prefix *)&tmp_prefix)) { + format = b->sid_format; + + if (!format) + continue; + + offset = format->block_len + format->node_len; + func_len = format->function_len; + + for (uint8_t idx = 0; idx < func_len; idx++) { + uint8_t tidx = offset + idx; + *sid_func |= (sid_value->s6_addr[tidx / 8] & + (0x1 << (7 - tidx % 8))) + << ((func_len - 1 - idx) / 8); + } + + /* + * If function comes from the Wide LIB range, we also + * need to get the Wide function. + */ + if (*sid_func >= format->config.usid.wlib_start && + *sid_func <= format->config.usid.wlib_end) { + format = b->sid_format; + + offset = format->block_len + format->node_len + + format->function_len; + + for (uint8_t idx = 0; idx < 16; idx++) { + uint8_t tidx = offset + idx; + *sid_wide_func |= + (sid_value->s6_addr[tidx / 8] & + (0x1 << (7 - tidx % 8))) + << (((16 - 1 - idx) / 8) * 8); + } + } + + *sid_block = b; + + return true; + } + } + + return false; +} + +/** + * Allocate an explicit SID function (i.e. specific SID function value) from a given SID block. + * + * @param block SRv6 SID block from which the SID function has to be allocated + * @param sid_func SID function to be allocated + * @param sid_wide_func SID wide function to be allocated + * + * @return true on success, false otherwise + */ +static bool alloc_srv6_sid_func_explicit(struct zebra_srv6_sid_block *block, + uint32_t sid_func, + uint32_t sid_wide_func) +{ + struct srv6_sid_format *format; + struct listnode *node; + uint32_t *sid_func_ptr = NULL; + + if (!block) + return false; + + format = block->sid_format; + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: trying to allocate explicit SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + + /* + * Allocate SID function from the corresponding range depending on the SID format type + */ + if (format) { + if (format->type == SRV6_SID_FORMAT_TYPE_USID) { + uint32_t elib_start = format->config.usid.elib_start; + uint32_t elib_end = format->config.usid.elib_end; + uint32_t wlib_end = format->config.usid.wlib_end; + uint32_t ewlib_start = format->config.usid.ewlib_start; + uint32_t ewlib_end = wlib_end; + uint32_t *sid_wide_func_ptr = NULL; + + /* Figure out the range from which the SID function has been allocated and release it */ + if ((sid_func >= elib_start) && (sid_func <= elib_end)) { + /* The SID function has to be allocated from the ELIB range */ + + /* Ensure that the requested SID function has not already been taken */ + for (ALL_LIST_ELEMENTS_RO(block->u.usid.lib + .func_allocated, + node, sid_func_ptr)) + if (*sid_func_ptr == sid_func) + break; + + if (sid_func_ptr) { + zlog_err("%s: invalid SM request arguments: SID function %u already taken", + __func__, sid_func); + return false; + } + + /* + * Mark the SID function as "taken" by adding it to the "func_allocated" list and + * increase the counter of function allocated + */ + sid_func_ptr = + zebra_srv6_sid_func_alloc(sid_func); + listnode_add(block->u.usid.lib.func_allocated, + sid_func_ptr); + block->u.usid.lib.num_func_allocated++; + } else if ((sid_func >= ewlib_start) && + (sid_func <= ewlib_end)) { + /* The SID function has to be allocated from the EWLIB range */ + + /* Ensure that the requested SID function has not already been taken */ + for (ALL_LIST_ELEMENTS_RO(block->u.usid + .wide_lib[sid_func] + .func_allocated, + node, + sid_wide_func_ptr)) + if (*sid_wide_func_ptr == sid_wide_func) + break; + + if (sid_wide_func_ptr) { + zlog_err("%s: invalid SM request arguments: SID function %u already taken", + __func__, sid_func); + return false; + } + + /* + * Mark the SID function as "taken" by adding it to the "func_allocated" list and + * increase the counter of function allocated + */ + sid_wide_func_ptr = zebra_srv6_sid_func_alloc( + sid_wide_func); + listnode_add(block->u.usid.wide_lib[sid_func] + .func_allocated, + sid_wide_func_ptr); + block->u.usid.wide_lib[sid_func] + .num_func_allocated++; + } else { + zlog_warn("%s: function %u is outside ELIB [%u/%u] and EWLIB alloc ranges [%u/%u]", + __func__, sid_func, elib_start, + elib_end, ewlib_start, ewlib_end); + return -1; + } + } else if (format->type == SRV6_SID_FORMAT_TYPE_UNCOMPRESSED) { + uint32_t explicit_start = + format->config.uncompressed.explicit_start; + uint32_t explicit_end = + (uint32_t)((1 << format->function_len) - 1); + + /* Ensure that the SID function comes from the Explicit range */ + if (!(sid_func >= explicit_start && + sid_func <= explicit_end)) { + zlog_err("%s: invalid SM request arguments: SID function %u out of explicit range (%u - %u)", + __func__, sid_func, explicit_start, + explicit_end); + return false; + } + + /* Ensure that the SID function has not already been taken */ + + for (ALL_LIST_ELEMENTS_RO(block->u.uncompressed + .func_allocated, + node, sid_func_ptr)) + if (*sid_func_ptr == sid_func) + break; + + /* SID function already taken */ + if (sid_func_ptr) { + zlog_err("%s: invalid SM request arguments: SID function %u already taken", + __func__, sid_func); + return false; + } + + /* + * Mark the SID function as "taken" by adding it to the "func_allocated" list and + * increase the counter of function allocated + */ + sid_func_ptr = zebra_srv6_sid_func_alloc(sid_func); + listnode_add(block->u.uncompressed.func_allocated, + sid_func_ptr); + block->u.uncompressed.num_func_allocated++; + } else { + /* We should never arrive here */ + zlog_err("%s: unknown SID format type: %u", __func__, + format->type); + assert(0); + } + } else { + /* Ensure that the SID function has not already been taken */ + + for (ALL_LIST_ELEMENTS_RO(block->u.uncompressed.func_allocated, + node, sid_func_ptr)) + if (*sid_func_ptr == sid_func) + break; + + /* SID function already taken */ + if (sid_func_ptr) { + zlog_err("%s: invalid SM request arguments: SID function %u already taken", + __func__, sid_func); + return false; + } + + /* + * Mark the SID function as "taken" by adding it to the "func_allocated" list and + * increase the counter of function allocated + */ + sid_func_ptr = zebra_srv6_sid_func_alloc(sid_func); + listnode_add(block->u.uncompressed.func_allocated, sid_func_ptr); + block->u.uncompressed.num_func_allocated++; + } + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: allocated explicit SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + + return true; +} + +/** + * Allocate a dynamic SID function (i.e. any available SID function value) from a given SID block. + * + * @param block SRv6 SID block from which the SID function has to be allocated + * @param sid_func SID function allocated + * + * @return true on success, false otherwise + */ +static bool alloc_srv6_sid_func_dynamic(struct zebra_srv6_sid_block *block, + uint32_t *sid_func) +{ + struct srv6_sid_format *format; + uint32_t *sid_func_ptr = NULL; + + if (!block || !sid_func) + return false; + + format = block->sid_format; + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: trying to allocate dynamic SID function from block %pFX", + __func__, &block->prefix); + + /* + * Allocate SID function from the corresponding range depending on the SID format type + */ + if (format) { + if (format->type == SRV6_SID_FORMAT_TYPE_USID) { + /* Format is uSID and behavior => allocate SID function from LIB range */ + + /* The Dynamic LIB range ends where the Explicit LIB range begins */ + uint32_t dlib_end = format->config.usid.elib_start - 1; + + /* Check if we ran out of available SID functions */ + if (block->u.usid.lib.first_available_func > dlib_end) { + zlog_warn("%s: SRv6: Warning, SRv6 Dynamic LIB is depleted", + __func__); + return false; + } + + /* + * First, let's check if there are any SID functions that were previously + * allocated and then released. + */ + if (listcount(block->u.usid.lib.func_released) != 0) { + /* + * There are SID functions previously allocated and then released, + * let's pick the first one and reuse it now. + */ + sid_func_ptr = listnode_head( + block->u.usid.lib.func_released); + *sid_func = *sid_func_ptr; + listnode_delete(block->u.usid.lib.func_released, + sid_func_ptr); + zebra_srv6_sid_func_free(sid_func_ptr); + } else { + /* + * There are no SID functions previously allocated and then released, + * let's allocate a new function from the pool of available functions. + */ + *sid_func = + block->u.usid.lib.first_available_func; + block->u.usid.lib.first_available_func++; + } + + /* Increase the counter of SID functions allocated */ + block->u.usid.lib.num_func_allocated++; + + if (block->u.usid.lib.first_available_func > dlib_end) + zlog_warn("%s: SRv6: Warning, SRv6 Dynamic LIB is depleted and next SID request will fail", + __func__); + } else if (format->type == SRV6_SID_FORMAT_TYPE_UNCOMPRESSED) { + /* Format is uncompressed => allocate SID function from Dynamic range */ + + uint32_t dynamic_end = + format->config.uncompressed.explicit_start - 1; + + /* Check if we ran out of available SID functions */ + if (block->u.uncompressed.first_available_func > + dynamic_end) { + zlog_warn("%s: SRv6: Warning, SRv6 SID Dynamic alloc space is depleted", + __func__); + return NULL; + } + + /* + * First, let's check if there are any SID functions that were previously + * allocated and then released. + */ + if (listcount(block->u.uncompressed.func_released) != 0) { + /* + * There are SID functions previously allocated and then released, + * let's pick the first one and reuse it now. + */ + sid_func_ptr = listnode_head( + block->u.uncompressed.func_released); + *sid_func = *sid_func_ptr; + listnode_delete(block->u.uncompressed + .func_released, + sid_func_ptr); + zebra_srv6_sid_func_free(sid_func_ptr); + } else { + /* + * There are no SID functions previously allocated and then released, + * let's allocate a new function from the pool of available functions. + */ + *sid_func = block->u.uncompressed + .first_available_func; + block->u.uncompressed.first_available_func++; + } + + /* Increase the counter of SID functions allocated */ + block->u.uncompressed.num_func_allocated++; + + if (block->u.uncompressed.first_available_func > + dynamic_end) + zlog_warn("%s: SRv6: Warning, SRv6 SID Dynamic alloc space is depleted and next SID request will fail", + __func__); + } else { + /* We should never arrive here */ + zlog_err("%s: unknown SID format type: %u", __func__, + format->type); + assert(0); + } + } else { + /* + * First, let's check if there are any SID functions that were previously + * allocated and then released. + */ + if (listcount(block->u.uncompressed.func_released) != 0) { + /* + * There are SID functions previously allocated and then released, + * let's pick the first one and reuse it now. + */ + sid_func_ptr = listnode_head( + block->u.uncompressed.func_released); + *sid_func = *sid_func_ptr; + listnode_delete(block->u.uncompressed.func_released, + sid_func_ptr); + zebra_srv6_sid_func_free(sid_func_ptr); + } else { + /* + * There are no SID functions previously allocated and then released, + * let's allocate a new function from the pool of available functions. + */ + *sid_func = block->u.uncompressed.first_available_func; + block->u.uncompressed.first_available_func++; + } + + /* Increase the counter of SID functions allocated */ + block->u.uncompressed.num_func_allocated++; + } + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: allocated dynamic SID function %u from block %pFX", + __func__, *sid_func, &block->prefix); + + return true; +} + +/** + * Get an explicit SID (i.e., a specific SID value) for a given context. + * + * If a SID already exists associated with the context, it returns the existing SID. + * Otherwise, it allocates a new SID. + * + * @param sid SID returned + * @param ctx Context for which the SID has been requested + * @param sid_value specific SRv6 SID value (i.e. IPv6 address) to be + * allocated explicitly + * + * @return 0 if the function returned an existing SID and SID value has not changed, + * 1 if a new SID has been allocated or the existing SID value has changed, -1 if an error occurred + */ +static int get_srv6_sid_explicit(struct zebra_srv6_sid **sid, + struct srv6_sid_ctx *ctx, + struct in6_addr *sid_value) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct zebra_srv6_sid_ctx *s = NULL; + struct zebra_srv6_sid_ctx *zctx = NULL; + struct listnode *node; + uint32_t sid_func = 0, sid_func_wide = 0; + struct srv6_locator *locator = NULL; + struct zebra_srv6_sid_block *block = NULL; + char buf[256]; + + if (!ctx || !sid_value) + return -1; + + /* Check if we already have a SID associated with the provided context */ + for (ALL_LIST_ELEMENTS_RO(srv6->sids, node, s)) { + if (memcmp(&s->ctx, ctx, sizeof(struct srv6_sid_ctx)) == 0) { + /* + * If the context is already associated with a SID that has the same SID value, then + * return the existing SID + */ + if (sid_same(&s->sid->value, sid_value)) { + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: returning existing SRv6 SID %pI6 ctx %s", + __func__, &s->sid->value, + srv6_sid_ctx2str(buf, + sizeof(buf), + ctx)); + *sid = s->sid; + return 0; + } + + /* + * It is not allowed to allocate an explicit SID for a given context if the context + * is already associated with an explicit SID + */ + if (s->sid->alloc_mode == SRV6_SID_ALLOC_MODE_EXPLICIT) { + zlog_err("%s: cannot alloc SID %pI6 for ctx %s: ctx already associated with SID %pI6", + __func__, sid_value, + srv6_sid_ctx2str(buf, sizeof(buf), + &s->ctx), + &s->sid->value); + return -1; + } + + zctx = s; + break; + } + } + + /* Get parent locator and function of the provided SID */ + if (!zebra_srv6_sid_decompose(sid_value, &block, &locator, &sid_func, + &sid_func_wide)) { + zlog_err("%s: invalid SM request arguments: parent block/locator not found for SID %pI6", + __func__, sid_value); + return -1; + } + + if (ctx->behavior == ZEBRA_SEG6_LOCAL_ACTION_END) { + zlog_err("%s: invalid SM request arguments: explicit SID allocation not allowed for End/uN behavior", + __func__); + return -1; + } + + /* Allocate an explicit SID function for the SID */ + if (!alloc_srv6_sid_func_explicit(block, sid_func, sid_func_wide)) { + zlog_err("%s: invalid SM request arguments: failed to allocate SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + return -1; + } + + if (!zctx) { + /* If we don't have a zebra SID context for this context, allocate a new one */ + zctx = zebra_srv6_sid_ctx_alloc(); + zctx->ctx = *ctx; + } else { + /* + * If we already have a SID associated with this context, we need to + * deallocate the current SID function before allocating the new one + */ + if (zctx->sid) { + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: ctx %s already associated with a dynamic SID %pI6, releasing dynamic SID", + __func__, + srv6_sid_ctx2str(buf, sizeof(buf), + ctx), + &zctx->sid->value); + + release_srv6_sid_func_dynamic(block, zctx->sid->func); + zebra_srv6_sid_free(zctx->sid); + zctx->sid = NULL; + } + } + + /* Allocate the SID to store SID information */ + *sid = zebra_srv6_sid_alloc(zctx, sid_value, locator, block, sid_func, + SRV6_SID_ALLOC_MODE_EXPLICIT); + if (!(*sid)) { + flog_err(EC_ZEBRA_SM_CANNOT_ASSIGN_SID, + "%s: failed to create SRv6 SID %s (%pI6)", __func__, + srv6_sid_ctx2str(buf, sizeof(buf), ctx), sid_value); + return -1; + } + (*sid)->ctx = zctx; + zctx->sid = *sid; + listnode_add(srv6->sids, zctx); + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: allocated explicit SRv6 SID %pI6 for context %s", + __func__, &(*sid)->value, + srv6_sid_ctx2str(buf, sizeof(buf), ctx)); + + return 1; +} + +/** + * Get a dynamic SID (i.e., any available SID value) for a given context. + * + * If a SID already exists associated with the context, it returns the existing SID. + * Otherwise, it allocates a new SID. + * + * @param sid SID returned + * @param ctx Context for which the SID has been requested + * @param locator SRv6 locator from which the SID has to be allocated + * + * @return 0 if the function returned an existing SID and SID value has not changed, + * 1 if a new SID has been allocated or the existing SID value has changed, -1 if an error occurred + */ +static int get_srv6_sid_dynamic(struct zebra_srv6_sid **sid, + struct srv6_sid_ctx *ctx, + struct srv6_locator *locator) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct zebra_srv6_sid_block *block; + struct srv6_sid_format *format; + struct zebra_srv6_sid_ctx *s = NULL; + struct zebra_srv6_sid_ctx *zctx; + struct listnode *node; + struct in6_addr sid_value; + uint32_t sid_func = 0; + char buf[256]; + + if (!ctx || !locator) + return -1; + + block = locator->sid_block; + format = locator->sid_format; + + /* + * If we already have a SID for the provided context, we return the existing + * SID instead of allocating a new one. + */ + for (ALL_LIST_ELEMENTS_RO(srv6->sids, node, s)) { + if (locator && s->sid && s->sid->locator) { + if (strncmp(s->sid->locator->name, locator->name, + SRV6_LOCNAME_SIZE)) { + continue; + } + } + if (memcmp(&s->ctx, ctx, sizeof(struct srv6_sid_ctx)) == 0) { + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: returning existing SID %s %pI6", + __func__, + srv6_sid_ctx2str(buf, sizeof(buf), + ctx), + &s->sid->value); + *sid = s->sid; + return 0; + } + } + + if (format && format->type == SRV6_SID_FORMAT_TYPE_USID && + ctx->behavior == ZEBRA_SEG6_LOCAL_ACTION_END) { + /* uN SID is allocated from the GIB range */ + sid_value = locator->prefix.prefix; + } else if (!format && ctx->behavior == ZEBRA_SEG6_LOCAL_ACTION_END) { + /* uN SID is allocated from the GIB range */ + sid_value = locator->prefix.prefix; + } else { + /* Allocate a dynamic SID function for the SID */ + if (!alloc_srv6_sid_func_dynamic(block, &sid_func)) { + zlog_err("%s: invalid SM request arguments: failed to allocate SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + return -1; + } + + /* Compose the SID as the locator followed by the SID function */ + zebra_srv6_sid_compose(&sid_value, locator, sid_func); + } + + /* Allocate a zebra SID context to store SID context information */ + zctx = zebra_srv6_sid_ctx_alloc(); + zctx->ctx = *ctx; + + /* Allocate the SID to store SID information */ + *sid = zebra_srv6_sid_alloc(zctx, &sid_value, locator, block, sid_func, + SRV6_SID_ALLOC_MODE_DYNAMIC); + if (!(*sid)) { + flog_err(EC_ZEBRA_SM_CANNOT_ASSIGN_SID, + "%s: failed to create SRv6 SID ctx %s (%pI6)", __func__, + srv6_sid_ctx2str(buf, sizeof(buf), ctx), &sid_value); + return -1; + } + (*sid)->ctx = zctx; + zctx->sid = *sid; + listnode_add(srv6->sids, zctx); + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: allocated new dynamic SRv6 SID %pI6 for context %s", + __func__, &(*sid)->value, + srv6_sid_ctx2str(buf, sizeof(buf), ctx)); + + return 1; +} + +/** + * Get an SRv6 SID for a given context. + * + * If a SID already exists associated with the context, it returns the existing SID. + * Otherwise, it allocates a new SID. + * + * If the sid_value parameter is non-NULL, it allocates the requested SID value + * if it is available (explicit SID allocation). + * If the sid_value parameter is NULL, it allocates any available SID value + * (dynamic SID allocation). + * + * @param sid SID returned + * @param ctx Context for which the SID has been requested + * @param sid_value SRv6 SID value to be allocated (for explicit SID allocation) + * @param locator_name Parent SRv6 locator from which the SID has to be allocated (for dynamic SID allocation) + * + * @return 0 if the function returned an existing SID and SID value has not changed, + * 1 if a new SID has been allocated or the existing SID value has changed, -1 if an error occurred + */ +int get_srv6_sid(struct zebra_srv6_sid **sid, struct srv6_sid_ctx *ctx, + struct in6_addr *sid_value, const char *locator_name) +{ + int ret = -1; + struct srv6_locator *locator; + char buf[256]; + + enum srv6_sid_alloc_mode alloc_mode = + (sid_value) ? SRV6_SID_ALLOC_MODE_EXPLICIT + : SRV6_SID_ALLOC_MODE_DYNAMIC; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: received SRv6 SID alloc request: SID ctx %s (%pI6), mode=%s", + __func__, srv6_sid_ctx2str(buf, sizeof(buf), ctx), + sid_value, srv6_sid_alloc_mode2str(alloc_mode)); + + if (alloc_mode == SRV6_SID_ALLOC_MODE_EXPLICIT) { + /* + * Explicit SID allocation: allocate a specific SID value + */ + + if (!sid_value) { + zlog_err("%s: invalid SM request arguments: missing SRv6 SID value, necessary for explicit allocation", + __func__); + return -1; + } + + ret = get_srv6_sid_explicit(sid, ctx, sid_value); + } else { + /* + * Dynamic SID allocation: allocate any available SID value + */ + + if (!locator_name) { + zlog_err("%s: invalid SM request arguments: missing SRv6 locator, necessary for dynamic allocation", + __func__); + return -1; + } + + locator = zebra_srv6_locator_lookup(locator_name); + if (!locator) { + zlog_err("%s: invalid SM request arguments: SRv6 locator '%s' does not exist", + __func__, locator_name); + return -1; + } + + ret = get_srv6_sid_dynamic(sid, ctx, locator); + } + + return ret; +} + +/** + * Release an explicit SRv6 SID function. + * + * @param block Parent SRv6 SID block of the SID function that has to be released + * @param sid_func SID function to be released + * @return 0 on success, -1 otherwise + */ +static bool release_srv6_sid_func_explicit(struct zebra_srv6_sid_block *block, + uint32_t sid_func, + uint32_t sid_wide_func) +{ + struct srv6_sid_format *format; + struct listnode *node; + uint32_t *sid_func_ptr = NULL; + + if (!block) + return -1; + + format = block->sid_format; + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: trying to release explicit SRv6 SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + + /* + * Release SID function from the corresponding range depending on the SID format type + */ + if (format) { + if (format->type == SRV6_SID_FORMAT_TYPE_USID) { + uint32_t elib_start = format->config.usid.elib_start; + uint32_t elib_end = format->config.usid.elib_end; + uint32_t ewlib_start = format->config.usid.ewlib_start; + uint32_t ewlib_end = format->config.usid.wlib_end; + uint32_t *sid_wide_func_ptr = NULL; + + /* Figure out the range from which the SID function has been allocated and release it */ + if ((sid_func >= elib_start) && (sid_func <= elib_end)) { + /* The SID function comes from the ELIB range */ + + /* Lookup SID function in the functions allocated list of ELIB range */ + for (ALL_LIST_ELEMENTS_RO(block->u.usid.lib + .func_allocated, + node, sid_func_ptr)) + if (*sid_func_ptr == sid_func) + break; + + /* Ensure that the SID function is allocated */ + if (!sid_func_ptr) { + zlog_warn("%s: failed to release SID function %u, function is not allocated", + __func__, sid_func); + return -1; + } + + /* Release the SID function from the ELIB range */ + listnode_delete(block->u.usid.lib.func_allocated, + sid_func_ptr); + zebra_srv6_sid_func_free(sid_func_ptr); + } else if ((sid_func >= ewlib_start) && + (sid_func <= ewlib_end)) { + /* The SID function comes from the EWLIB range */ + + /* Lookup SID function in the functions allocated list of EWLIB range */ + for (ALL_LIST_ELEMENTS_RO(block->u.usid + .wide_lib[sid_func] + .func_allocated, + node, sid_wide_func_ptr)) + if (*sid_wide_func_ptr == sid_wide_func) + break; + + /* Ensure that the SID function is allocated */ + if (!sid_wide_func_ptr) { + zlog_warn("%s: failed to release wide SID function %u, function is not allocated", + __func__, sid_wide_func); + return -1; + } + + /* Release the SID function from the EWLIB range */ + listnode_delete(block->u.usid.wide_lib[sid_func] + .func_allocated, + sid_wide_func_ptr); + zebra_srv6_sid_func_free(sid_wide_func_ptr); + } else { + zlog_warn("%s: function %u is outside ELIB [%u/%u] and EWLIB alloc ranges [%u/%u]", + __func__, sid_func, elib_start, + elib_end, ewlib_start, ewlib_end); + return -1; + } + } else if (format->type == SRV6_SID_FORMAT_TYPE_UNCOMPRESSED) { + uint32_t explicit_start = + format->config.uncompressed.explicit_start; + uint32_t explicit_end = + (uint32_t)((1 << format->function_len) - 1); + + /* Ensure that the SID function comes from the Explicit range */ + if (!(sid_func >= explicit_start && + sid_func <= explicit_end)) { + zlog_warn("%s: function %u is outside explicit alloc range [%u/%u]", + __func__, sid_func, explicit_start, + explicit_end); + return -1; + } + + /* Lookup SID function in the functions allocated list of Explicit range */ + for (ALL_LIST_ELEMENTS_RO(block->u.uncompressed + .func_allocated, + node, sid_func_ptr)) + if (*sid_func_ptr == sid_func) + break; + + /* Ensure that the SID function is allocated */ + if (!sid_func_ptr) { + zlog_warn("%s: failed to release SID function %u, function is not allocated", + __func__, sid_func); + return -1; + } + + /* Release the SID function from the Explicit range */ + listnode_delete(block->u.uncompressed.func_allocated, + sid_func_ptr); + zebra_srv6_sid_func_free(sid_func_ptr); + } else { + /* We should never arrive here */ + assert(0); + } + } else { + /* Lookup SID function in the functions allocated list of Explicit range */ + for (ALL_LIST_ELEMENTS_RO(block->u.uncompressed.func_allocated, + node, sid_func_ptr)) + if (*sid_func_ptr == sid_func) + break; + + /* Ensure that the SID function is allocated */ + if (!sid_func_ptr) { + zlog_warn("%s: failed to release SID function %u, function is not allocated", + __func__, sid_func); + return -1; + } + + /* Release the SID function from the Explicit range */ + listnode_delete(block->u.uncompressed.func_allocated, + sid_func_ptr); + zebra_srv6_sid_func_free(sid_func_ptr); + } + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: released explicit SRv6 SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + + return 0; +} + +/** + * Release a dynamic SRv6 SID function. + * + * @param block Parent SRv6 SID block of the SID function that has to be released + * @param sid_func SID function to be released + * @return 0 on success, -1 otherwise + */ +static int release_srv6_sid_func_dynamic(struct zebra_srv6_sid_block *block, + uint32_t sid_func) +{ + struct srv6_sid_format *format; + struct listnode *node, *nnode; + uint32_t *sid_func_ptr = NULL; + + if (!block) + return -1; + + format = block->sid_format; + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: trying to release dynamic SRv6 SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + + /* + * Release SID function from the corresponding range depending on the SID format type + */ + if (format && format->type == SRV6_SID_FORMAT_TYPE_USID) { + uint32_t dlib_start = format->config.usid.lib_start; + /* The Dynamic LIB range ends where the Explicit LIB range begins */ + uint32_t dlib_end = format->config.usid.elib_start - 1; + + /* Ensure that the SID function to be released comes from the Dynamic LIB (DLIB) range */ + if (!(sid_func >= dlib_start && sid_func <= dlib_end)) { + zlog_warn("%s: function %u is outside Dynamic LIB range [%u/%u]", + __func__, sid_func, dlib_start, dlib_end); + return -1; + } + + if (sid_func == block->u.usid.lib.first_available_func - 1) { + /* + * The SID function to be released precedes the `first_available_func`. + * Reset first_available_func to the first available position. + */ + + block->u.usid.lib.first_available_func -= 1; + + bool found; + + do { + found = false; + for (ALL_LIST_ELEMENTS(block->u.usid.lib + .func_released, + node, nnode, + sid_func_ptr)) + if (*sid_func_ptr == + block->u.usid.lib.first_available_func - + 1) { + listnode_delete(block->u.usid + .lib + .func_released, + sid_func_ptr); + zebra_srv6_sid_func_free( + sid_func_ptr); + block->u.usid.lib + .first_available_func -= + 1; + found = true; + break; + } + } while (found); + } else { + /* + * The SID function to be released does not precede the `first_available_func`. + * Add the released function to the func_released array to indicate + * that it is available again for allocation. + */ + sid_func_ptr = zebra_srv6_sid_func_alloc(sid_func); + listnode_add_head(block->u.usid.lib.func_released, + sid_func_ptr); + } + } else if (format && format->type == SRV6_SID_FORMAT_TYPE_UNCOMPRESSED) { + uint32_t dynamic_start = + SRV6_SID_FORMAT_UNCOMPRESSED_F4024_FUNC_UNRESERVED_MIN; + /* The Dynamic range ends where the Explicit range begins */ + uint32_t dynamic_end = + format->config.uncompressed.explicit_start - 1; + + /* Ensure that the SID function to be released comes from the Dynamic range */ + if (!(sid_func >= dynamic_start && sid_func <= dynamic_end)) { + zlog_warn("%s: function %u is outside dynamic range [%u/%u]", + __func__, sid_func, dynamic_start, + dynamic_end); + return -1; + } + + if (sid_func == block->u.uncompressed.first_available_func - 1) { + /* + * The released SID function precedes the `first_available_func`. + * Reset first_available_func to the first available position. + */ + + block->u.uncompressed.first_available_func -= 1; + + bool found; + + do { + found = false; + for (ALL_LIST_ELEMENTS(block->u.uncompressed + .func_released, + node, nnode, + sid_func_ptr)) + if (*sid_func_ptr == + block->u.uncompressed + .first_available_func - + 1) { + listnode_delete(block->u.uncompressed + .func_released, + sid_func_ptr); + zebra_srv6_sid_func_free( + sid_func_ptr); + block->u.uncompressed + .first_available_func -= + 1; + found = true; + break; + } + } while (found); + } else { + /* + * The released SID function does not precede the `first_available_func`. + * Add the released function to the func_released array to indicate + * that it is available again for allocation. + */ + sid_func_ptr = zebra_srv6_sid_func_alloc(sid_func); + listnode_add_head(block->u.uncompressed.func_released, + sid_func_ptr); + } + } else if (!format) { + if (sid_func == block->u.uncompressed.first_available_func - 1) { + /* + * The released SID function precedes the `first_available_func`. + * Reset first_available_func to the first available position. + */ + + block->u.uncompressed.first_available_func -= 1; + + bool found; + + do { + found = false; + for (ALL_LIST_ELEMENTS(block->u.uncompressed + .func_released, + node, nnode, + sid_func_ptr)) + if (*sid_func_ptr == + block->u.uncompressed + .first_available_func - + 1) { + listnode_delete(block->u.uncompressed + .func_released, + sid_func_ptr); + zebra_srv6_sid_func_free( + sid_func_ptr); + block->u.uncompressed + .first_available_func -= + 1; + found = true; + break; + } + } while (found); + } else { + /* + * The released SID function does not precede the `first_available_func`. + * Add the released function to the func_released array to indicate + * that it is available again for allocation. + */ + sid_func_ptr = zebra_srv6_sid_func_alloc(sid_func); + listnode_add_head(block->u.uncompressed.func_released, + sid_func_ptr); + } + } + + if (ZEBRA_DEBUG_PACKET) + zlog_debug("%s: released dynamic SRv6 SID function %u from block %pFX", + __func__, sid_func, &block->prefix); + + return 0; +} + +/** + * Core function, release the SRv6 SID associated with a given context. + * + * @param client The client for which the SID has to be released + * @param ctx Context associated with the SRv6 SID to be released + * @return 0 on success, -1 otherwise + */ +int release_srv6_sid(struct zserv *client, struct zebra_srv6_sid_ctx *zctx) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + char buf[256]; + + if (!zctx || !zctx->sid) + return -1; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: releasing SRv6 SID %pI6 associated with ctx %s (proto=%u, instance=%u)", + __func__, &zctx->sid->value, + srv6_sid_ctx2str(buf, sizeof(buf), &zctx->ctx), + client->proto, client->instance); + + /* Ensures the SID is in use by the client */ + if (!listnode_lookup(zctx->sid->client_list, client)) { + flog_err(EC_ZEBRA_SM_DAEMON_MISMATCH, "%s: Daemon mismatch!!", + __func__); + return -1; + } + + /* Remove the client from the list of clients using the SID */ + listnode_delete(zctx->sid->client_list, client); + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: released SRv6 SID %pI6 associated with ctx %s (proto=%u, instance=%u)", + __func__, &zctx->sid->value, + srv6_sid_ctx2str(buf, sizeof(buf), &zctx->ctx), + client->proto, client->instance); + + /* + * If the SID is not used by any other client, then deallocate it + * and remove it from the SRv6 database. + */ + if (listcount(zctx->sid->client_list) == 0) { + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: SRv6 SID %pI6 associated with ctx %s is no longer in use, removing it from SRv6 database", + __func__, &zctx->sid->value, + srv6_sid_ctx2str(buf, sizeof(buf), + &zctx->ctx)); + + if (!(zctx->sid->block->sid_format && + zctx->sid->block->sid_format->type == + SRV6_SID_FORMAT_TYPE_USID && + zctx->ctx.behavior == ZEBRA_SEG6_LOCAL_ACTION_END) && + !(!zctx->sid->block->sid_format && + zctx->ctx.behavior == ZEBRA_SEG6_LOCAL_ACTION_END)) { + if (zctx->sid->alloc_mode == + SRV6_SID_ALLOC_MODE_EXPLICIT) + /* Release SRv6 SID function */ + release_srv6_sid_func_explicit(zctx->sid->block, + zctx->sid->func, + zctx->sid->wide_func); + else if (zctx->sid->alloc_mode == + SRV6_SID_ALLOC_MODE_DYNAMIC) + /* Release SRv6 SID function */ + release_srv6_sid_func_dynamic(zctx->sid->block, + zctx->sid->func); + else + /* We should never arrive here */ + assert(0); + } + + /* Free the SID */ + zebra_srv6_sid_free(zctx->sid); + zctx->sid = NULL; + + /* Remove the SID context from the list and free memory */ + listnode_delete(srv6->sids, zctx); + zebra_srv6_sid_ctx_free(zctx); + } + + return 0; +} + +/** + * Handle a get SRv6 Locator request received from a client. + * + * It looks up the requested locator and send it to the client. + * + * @param locator SRv6 locator returned by this function + * @param client The client that sent the Get SRv6 Locator request + * @param locator_name Name of the locator to look up + * + * @return 0 on success + */ +static int srv6_manager_get_srv6_locator_internal(struct srv6_locator **locator, + struct zserv *client, + const char *locator_name) +{ + *locator = zebra_srv6_locator_lookup(locator_name); + if (!*locator) + return -1; + + return zsend_zebra_srv6_locator_add(client, *locator); +} + +/** + * Handle a get SID request received from a client. + * + * It gets a SID for a given context. If there is no SID associated with the context yet, + * we allocate one and return it to the client. Otherwise, we return the existing SID. + * + * - When the `sid_value` parameter is non-NULL, SRv6 Manager assigns the requested SID value + * if it is available (explicit SID allocation). + * - When the `sid_value` parameter is NULL, SRv6 Manager assigns any available SID value + * (dynamic SID allocation). + * + * Finally, notify the client whether the SID allocation was successful or failed. + * + * @param sid SID returned by this function + * @param client The client that requested the SID + * @param ctx Context for which the SID was requested + * @param sid_value SID value (i.e., IPv6 address) that has to be assigned to the SID + * (for explicit SID allocation) + * @param locator_name Locator from which the SID has to be allocated (for dynamic SID allocation) + * + * @return 0 on success, -1 otherwise + */ +static int srv6_manager_get_sid_internal(struct zebra_srv6_sid **sid, + struct zserv *client, + struct srv6_sid_ctx *ctx, + struct in6_addr *sid_value, + const char *locator_name) +{ + int ret = -1; + struct listnode *node; + struct zserv *c; + char buf[256]; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: getting SRv6 SID for ctx %s, sid_value=%pI6, locator_name=%s", + __func__, srv6_sid_ctx2str(buf, sizeof(buf), ctx), + sid_value ? sid_value : &in6addr_any, locator_name); + + ret = get_srv6_sid(sid, ctx, sid_value, locator_name); + if (ret < 0) { + zlog_warn("%s: not got SRv6 SID for ctx %s, sid_value=%pI6, locator_name=%s", + __func__, srv6_sid_ctx2str(buf, sizeof(buf), ctx), + sid_value ? sid_value : &in6addr_any, locator_name); + + /* Notify client about SID alloc failure */ + zsend_srv6_sid_notify(client, ctx, sid_value, 0, 0, NULL, + ZAPI_SRV6_SID_FAIL_ALLOC); + } else if (ret == 0) { + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: got existing SRv6 SID for ctx %s: sid_value=%pI6 (func=%u) (proto=%u, instance=%u, sessionId=%u), notify client", + __func__, + srv6_sid_ctx2str(buf, sizeof(buf), ctx), + &(*sid)->value, (*sid)->func, client->proto, + client->instance, client->session_id); + if (!listnode_lookup((*sid)->client_list, client)) + listnode_add((*sid)->client_list, client); + + zsend_srv6_sid_notify(client, ctx, &(*sid)->value, (*sid)->func, + (*sid)->wide_func, + (*sid)->locator ? (*sid)->locator->name + : NULL, + ZAPI_SRV6_SID_ALLOCATED); + } else { + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: got new SRv6 SID for ctx %s: sid_value=%pI6 (func=%u) (proto=%u, instance=%u, sessionId=%u), notifying all clients", + __func__, + srv6_sid_ctx2str(buf, sizeof(buf), ctx), + &(*sid)->value, (*sid)->func, client->proto, + client->instance, client->session_id); + if (!listnode_lookup((*sid)->client_list, client)) + listnode_add((*sid)->client_list, client); + + for (ALL_LIST_ELEMENTS_RO((*sid)->client_list, node, c)) + zsend_srv6_sid_notify(c, ctx, &(*sid)->value, + (*sid)->func, (*sid)->wide_func, + (*sid)->locator + ? (*sid)->locator->name + : NULL, + ZAPI_SRV6_SID_ALLOCATED); + } + + return ret; +} + +/** + * Release SRv6 SIDs from a client. + * + * Called on client disconnection or reconnection. + * + * @param client The client to release SIDs from + * @return Number of SIDs released + */ +int release_daemon_srv6_sids(struct zserv *client) +{ + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct listnode *node, *nnode; + struct zebra_srv6_sid_ctx *ctx; + int count = 0; + int ret; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: releasing SRv6 SIDs for client proto %s, instance %d, session %u", + __func__, zebra_route_string(client->proto), + client->instance, client->session_id); + + /* Iterate over the SIDs and release SIDs used by the client daemon */ + for (ALL_LIST_ELEMENTS(srv6->sids, node, nnode, ctx)) { + if (!listnode_lookup(ctx->sid->client_list, client)) + continue; + + ret = release_srv6_sid(client, ctx); + if (ret == 0) + count++; + } + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: released %d SRv6 SIDs", __func__, count); + + return count; +} + +/** + * Release SRv6 SIDs from a client. + * + * @param client The client zapi session + * @param ctx Context associated with the SRv6 SID + * @return 0 on success, -1 on failure + */ +static int srv6_manager_release_sid_internal(struct zserv *client, + struct srv6_sid_ctx *ctx) +{ + int ret = -1; + struct zebra_srv6 *srv6 = zebra_srv6_get_default(); + struct zebra_srv6_sid_ctx *zctx; + struct listnode *node, *nnode; + char buf[256]; + const char *locator_name = NULL; + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: releasing SRv6 SID associated with ctx %s", + __func__, srv6_sid_ctx2str(buf, sizeof(buf), ctx)); + + /* Lookup Zebra SID context and release it */ + for (ALL_LIST_ELEMENTS(srv6->sids, node, nnode, zctx)) + if (memcmp(&zctx->ctx, ctx, sizeof(struct srv6_sid_ctx)) == 0) { + if (zctx->sid && zctx->sid->locator) + locator_name = + (const char *)zctx->sid->locator->name; + ret = release_srv6_sid(client, zctx); + break; + } + + if (IS_ZEBRA_DEBUG_PACKET) + zlog_debug("%s: no SID associated with ctx %s", __func__, + srv6_sid_ctx2str(buf, sizeof(buf), ctx)); + + if (ret == 0) + zsend_srv6_sid_notify(client, ctx, NULL, 0, 0, locator_name, + ZAPI_SRV6_SID_RELEASED); + else + zsend_srv6_sid_notify(client, ctx, NULL, 0, 0, locator_name, + ZAPI_SRV6_SID_FAIL_RELEASE); + + return ret; +} + void zebra_srv6_terminate(void) { struct srv6_locator *locator; + struct srv6_sid_format *format; + struct zebra_srv6_sid_block *block; + struct zebra_srv6_sid_ctx *sid_ctx; - if (!srv6.locators) - return; + if (srv6.locators) { + while (listcount(srv6.locators)) { + locator = listnode_head(srv6.locators); + + listnode_delete(srv6.locators, locator); + srv6_locator_free(locator); + } - while (listcount(srv6.locators)) { - locator = listnode_head(srv6.locators); + list_delete(&srv6.locators); + } + + /* Free SRv6 SIDs */ + if (srv6.sids) { + while (listcount(srv6.sids)) { + sid_ctx = listnode_head(srv6.sids); - listnode_delete(srv6.locators, locator); - srv6_locator_free(locator); + listnode_delete(srv6.sids, sid_ctx); + zebra_srv6_sid_ctx_free(sid_ctx); + } + + list_delete(&srv6.sids); } - list_delete(&srv6.locators); + /* Free SRv6 SID blocks */ + if (srv6.sid_blocks) { + while (listcount(srv6.sid_blocks)) { + block = listnode_head(srv6.sid_blocks); + + listnode_delete(srv6.sid_blocks, block); + zebra_srv6_sid_block_free(block); + } + + list_delete(&srv6.sid_blocks); + } + + /* Free SRv6 SID formats */ + if (srv6.sid_formats) { + while (listcount(srv6.sid_formats)) { + format = listnode_head(srv6.sid_formats); + + srv6_sid_format_unregister(format); + srv6_sid_format_free(format); + } + + list_delete(&srv6.sid_formats); + } } void zebra_srv6_init(void) @@ -451,6 +2446,12 @@ void zebra_srv6_init(void) zebra_srv6_manager_get_locator_chunk); hook_register(srv6_manager_release_chunk, zebra_srv6_manager_release_locator_chunk); + + hook_register(srv6_manager_get_sid, srv6_manager_get_sid_internal); + hook_register(srv6_manager_release_sid, + srv6_manager_release_sid_internal); + hook_register(srv6_manager_get_locator, + srv6_manager_get_srv6_locator_internal); } bool zebra_srv6_is_enable(void) |