forked from acouzens/open5gs
696 lines
18 KiB
C
696 lines
18 KiB
C
#define TRACE_MODULE _sgw_context
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#include "core_debug.h"
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#include "core_pool.h"
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#include "core_index.h"
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#include "core_jsmn.h"
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#include "core_lib.h"
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#include "types.h"
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#include "gtp_path.h"
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#include "context.h"
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#include "sgw_context.h"
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static sgw_context_t self;
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index_declare(sgw_sess_pool, sgw_sess_t, MAX_NUM_OF_UE);
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index_declare(sgw_bearer_pool, sgw_bearer_t, MAX_NUM_OF_UE_BEARER);
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static int context_initialized = 0;
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status_t sgw_context_init()
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{
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d_assert(context_initialized == 0, return CORE_ERROR,
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"SGW context already has been initialized");
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memset(&self, 0, sizeof(sgw_context_t));
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index_init(&sgw_sess_pool, MAX_NUM_OF_UE);
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index_init(&sgw_bearer_pool, MAX_NUM_OF_UE_BEARER);
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list_init(&self.s11_node.local_list);
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list_init(&self.s11_node.remote_list);
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list_init(&self.s5c_node.local_list);
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list_init(&self.s5c_node.remote_list);
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self.sess_hash = hash_make();
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context_initialized = 1;
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return CORE_OK;
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}
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status_t sgw_context_final()
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{
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d_assert(context_initialized == 1, return CORE_ERROR,
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"SGW context already has been finalized");
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gtp_xact_delete_all(&self.s11_node);
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gtp_xact_delete_all(&self.s5c_node);
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sgw_sess_remove_all();
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d_assert(self.sess_hash, , "Null param");
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hash_destroy(self.sess_hash);
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if (index_size(&sgw_sess_pool) != pool_avail(&sgw_sess_pool))
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d_warn("%d not freed in sgw_sess_pool[%d] in SGW-Context",
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index_size(&sgw_sess_pool) - pool_avail(&sgw_sess_pool),
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index_size(&sgw_sess_pool));
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d_trace(3, "%d not freed in sgw_sess_pool[%d] in SGW-Context\n",
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index_size(&sgw_sess_pool) - pool_avail(&sgw_sess_pool),
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index_size(&sgw_sess_pool));
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index_final(&sgw_bearer_pool);
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index_final(&sgw_sess_pool);
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context_initialized = 0;
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return CORE_OK;
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}
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sgw_context_t* sgw_self()
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{
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return &self;
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}
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static status_t sgw_context_prepare()
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{
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self.s11_port = GTPV2_C_UDP_PORT;
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self.s11_node.port = GTPV2_C_UDP_PORT;
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self.s5c_port = GTPV2_C_UDP_PORT;
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self.s5c_node.port = GTPV2_C_UDP_PORT;
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self.s1u_port = GTPV1_U_UDP_PORT;
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self.s5u_port = GTPV1_U_UDP_PORT;
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return CORE_OK;
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}
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static status_t sgw_context_validation()
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{
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if (self.s11_node.addr == 0)
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{
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d_error("No MME.NEWORK.S11_ADDR in '%s'",
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context_self()->config.path);
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return CORE_ERROR;
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}
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if (self.s5c_node.addr == 0)
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{
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d_error("No PGW.NEWORK.S5C_ADDR in '%s'",
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context_self()->config.path);
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return CORE_ERROR;
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}
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if (self.s11_addr == 0)
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{
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d_error("No SGW.NEWORK.S11_ADDR in '%s'",
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context_self()->config.path);
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return CORE_ERROR;
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}
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if (self.s5c_addr == 0)
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{
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d_error("No SGW.NEWORK.S5C_ADDR in '%s'",
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context_self()->config.path);
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return CORE_ERROR;
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}
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if (self.s1u_addr == 0)
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{
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d_error("No SGW.NEWORK.S1U_ADDR in '%s'",
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context_self()->config.path);
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return CORE_ERROR;
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}
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if (self.s5u_addr == 0)
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{
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d_error("No SGW.NEWORK.S5U_ADDR in '%s'",
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context_self()->config.path);
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return CORE_ERROR;
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}
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return CORE_OK;
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}
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status_t sgw_context_parse_config()
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{
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status_t rv;
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config_t *config = &context_self()->config;
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char *json = config->json;
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jsmntok_t *token = config->token;
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typedef enum {
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START, ROOT,
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MME_START, MME_ROOT,
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SGW_START, SGW_ROOT,
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PGW_START, PGW_ROOT,
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SKIP, STOP
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} parse_state;
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parse_state state = START;
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parse_state stack = STOP;
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size_t root_tokens = 0;
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size_t mme_tokens = 0;
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size_t sgw_tokens = 0;
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size_t pgw_tokens = 0;
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size_t skip_tokens = 0;
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int i, j, m, n;
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int arr, size;
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rv = sgw_context_prepare();
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if (rv != CORE_OK) return rv;
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for (i = 0, j = 1; j > 0; i++, j--)
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{
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jsmntok_t *t = &token[i];
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j += t->size;
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switch (state)
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{
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case START:
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{
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state = ROOT;
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root_tokens = t->size;
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break;
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}
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case ROOT:
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{
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if (jsmntok_equal(json, t, "MME") == 0)
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{
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state = MME_START;
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}
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else if (jsmntok_equal(json, t, "SGW") == 0)
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{
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state = SGW_START;
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}
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else if (jsmntok_equal(json, t, "PGW") == 0)
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{
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state = PGW_START;
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}
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else
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{
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state = SKIP;
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stack = ROOT;
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skip_tokens = t->size;
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root_tokens--;
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if (root_tokens == 0) state = STOP;
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}
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break;
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}
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case MME_START:
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{
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state = MME_ROOT;
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mme_tokens = t->size;
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break;
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}
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case MME_ROOT:
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{
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if (jsmntok_equal(json, t, "NETWORK") == 0)
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{
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m = 1;
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size = 1;
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if ((t+1)->type == JSMN_ARRAY)
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{
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m = 2;
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}
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for (arr = 0; arr < size; arr++)
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{
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for (n = 1; n > 0; m++, n--)
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{
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n += (t+m)->size;
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if (jsmntok_equal(json, t+m, "S11_ADDR") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s11_node.addr = inet_addr(v);
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}
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else if (jsmntok_equal(json, t+m, "S11_PORT") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s11_node.port = atoi(v);
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}
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}
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}
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}
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state = SKIP;
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stack = MME_ROOT;
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skip_tokens = t->size;
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mme_tokens--;
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if (mme_tokens == 0) stack = ROOT;
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break;
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}
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case SGW_START:
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{
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state = SGW_ROOT;
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sgw_tokens = t->size;
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break;
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}
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case SGW_ROOT:
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{
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if (jsmntok_equal(json, t, "NETWORK") == 0)
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{
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m = 1;
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size = 1;
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if ((t+1)->type == JSMN_ARRAY)
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{
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m = 2;
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}
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for (arr = 0; arr < size; arr++)
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{
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for (n = 1; n > 0; m++, n--)
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{
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n += (t+m)->size;
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if (jsmntok_equal(json, t+m, "S11_ADDR") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s11_addr = inet_addr(v);
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}
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else if (jsmntok_equal(json, t+m, "S11_PORT") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s11_port = atoi(v);
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}
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else if (jsmntok_equal(json, t+m, "S5C_ADDR") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s5c_addr = inet_addr(v);
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}
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else if (jsmntok_equal(json, t+m, "S5C_PORT") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s5c_port = atoi(v);
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}
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else if (jsmntok_equal(json, t+m, "S1U_ADDR") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s1u_addr = inet_addr(v);
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}
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else if (jsmntok_equal(json, t+m, "S1U_PORT") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s1u_port = atoi(v);
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}
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else if (jsmntok_equal(json, t+m, "S5U_ADDR") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s5u_addr = inet_addr(v);
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}
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else if (jsmntok_equal(json, t+m, "S5U_PORT") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s5u_port = atoi(v);
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}
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}
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}
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}
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state = SKIP;
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stack = SGW_ROOT;
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skip_tokens = t->size;
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sgw_tokens--;
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if (sgw_tokens == 0) stack = ROOT;
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break;
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}
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case PGW_START:
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{
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state = PGW_ROOT;
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pgw_tokens = t->size;
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break;
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}
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case PGW_ROOT:
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{
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if (jsmntok_equal(json, t, "NETWORK") == 0)
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{
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m = 1;
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size = 1;
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if ((t+1)->type == JSMN_ARRAY)
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{
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m = 2;
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}
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for (arr = 0; arr < size; arr++)
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{
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for (n = 1; n > 0; m++, n--)
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{
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n += (t+m)->size;
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if (jsmntok_equal(json, t+m, "S5C_ADDR") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s5c_node.addr = inet_addr(v);
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}
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else if (jsmntok_equal(json, t+m, "S5C_PORT") == 0)
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{
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char *v = jsmntok_to_string(json, t+m+1);
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if (v) self.s5c_node.port = atoi(v);
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}
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}
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}
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}
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state = SKIP;
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stack = PGW_ROOT;
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skip_tokens = t->size;
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pgw_tokens--;
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if (pgw_tokens == 0) stack = ROOT;
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break;
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}
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case SKIP:
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{
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skip_tokens += t->size;
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skip_tokens--;
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if (skip_tokens == 0) state = stack;
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break;
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}
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case STOP:
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{
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break;
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}
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default:
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{
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d_error("Failed to parse configuration in the state(%u)",
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state);
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break;
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}
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}
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}
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rv = sgw_context_validation();
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if (rv != CORE_OK) return rv;
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return CORE_OK;
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}
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status_t sgw_context_setup_trace_module()
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{
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int gtp = context_self()->trace_level.gtp;
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int others = context_self()->trace_level.others;
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if (gtp)
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{
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extern int _sgw_sm;
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d_trace_level(&_sgw_sm, gtp);
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extern int _sgw_handler;
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d_trace_level(&_sgw_handler, gtp);
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extern int _gtp_path;
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d_trace_level(&_gtp_path, gtp);
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extern int _sgw_path;
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d_trace_level(&_sgw_path, gtp);
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extern int _tlv_msg;
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d_trace_level(&_tlv_msg, gtp);
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extern int _gtp_xact;
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d_trace_level(&_gtp_xact, gtp);
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}
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if (others)
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{
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extern int _mutex;
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d_trace_level(&_mutex, others);
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extern int _pkbuf;
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d_trace_level(&_pkbuf, others);
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extern int _context;
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d_trace_level(&_context, others);
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extern int _sgw_context;
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d_trace_level(&_sgw_context, others);
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}
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return CORE_OK;
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}
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static void *sess_hash_keygen(c_uint8_t *out, int *out_len,
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c_uint8_t *imsi, int imsi_len, c_int8_t *apn)
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{
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memcpy(out, imsi, imsi_len);
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core_cpystrn((char*)(out+imsi_len), apn, MAX_APN_LEN+1);
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*out_len = imsi_len+strlen((char*)(out+imsi_len));
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return out;
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}
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sgw_sess_t *sgw_sess_add(
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c_uint8_t *imsi, int imsi_len, c_int8_t *apn, c_uint8_t id)
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{
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sgw_sess_t *sess = NULL;
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sgw_bearer_t *bearer = NULL;
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d_assert(self.sess_hash, return NULL, "Null param");
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index_alloc(&sgw_sess_pool, &sess);
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d_assert(sess, return NULL, "Null param");
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sess->sgw_s11_teid = sess->index; /* derived from an index */
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sess->sgw_s11_addr = sgw_self()->s11_addr;
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sess->sgw_s5c_teid = sess->index; /* derived from an index */
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sess->sgw_s5c_addr = sgw_self()->s5c_addr;
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/* Set IMSI */
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sess->imsi_len = imsi_len;
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memcpy(sess->imsi, imsi, sess->imsi_len);
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core_buffer_to_bcd(sess->imsi, sess->imsi_len, sess->imsi_bcd);
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/* Set APN */
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core_cpystrn(sess->pdn.apn, apn, MAX_APN_LEN+1);
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list_init(&sess->bearer_list);
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bearer = sgw_bearer_add(sess, id);
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d_assert(bearer, sgw_sess_remove(sess); return NULL,
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"Can't add default bearer context");
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/* Generate Hash Key : IMSI + APN */
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sess_hash_keygen(sess->hash_keybuf, &sess->hash_keylen,
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imsi, imsi_len, apn);
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hash_set(self.sess_hash, sess->hash_keybuf, sess->hash_keylen, sess);
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return sess;
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}
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status_t sgw_sess_remove(sgw_sess_t *sess)
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{
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d_assert(self.sess_hash, return CORE_ERROR, "Null param");
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d_assert(sess, return CORE_ERROR, "Null param");
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hash_set(self.sess_hash, sess->hash_keybuf, sess->hash_keylen, NULL);
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sgw_bearer_remove_all(sess);
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index_free(&sgw_sess_pool, sess);
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return CORE_OK;
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}
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status_t sgw_sess_remove_all()
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{
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hash_index_t *hi = NULL;
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sgw_sess_t *sess = NULL;
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for (hi = sgw_sess_first(); hi; hi = sgw_sess_next(hi))
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{
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sess = sgw_sess_this(hi);
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sgw_sess_remove(sess);
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}
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return CORE_OK;
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}
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sgw_sess_t* sgw_sess_find(index_t index)
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{
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d_assert(index, return NULL, "Invalid Index");
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return index_find(&sgw_sess_pool, index);
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}
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sgw_sess_t* sgw_sess_find_by_teid(c_uint32_t teid)
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{
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return sgw_sess_find(teid);
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}
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sgw_sess_t* sgw_sess_find_by_imsi_apn(
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c_uint8_t *imsi, int imsi_len, c_int8_t *apn)
|
|
{
|
|
c_uint8_t keybuf[MAX_IMSI_LEN+MAX_APN_LEN+1];
|
|
int keylen = 0;
|
|
|
|
d_assert(self.sess_hash, return NULL, "Null param");
|
|
|
|
sess_hash_keygen(keybuf, &keylen, imsi, imsi_len, apn);
|
|
return (sgw_sess_t *)hash_get(self.sess_hash, keybuf, keylen);
|
|
}
|
|
|
|
sgw_sess_t *sgw_sess_find_or_add_by_message(gtp_message_t *gtp_message)
|
|
{
|
|
sgw_sess_t *sess = NULL;
|
|
|
|
gtp_create_session_request_t *req = >p_message->create_session_request;
|
|
c_int8_t apn[MAX_APN_LEN];
|
|
|
|
if (req->sender_f_teid_for_control_plane.presence == 0)
|
|
{
|
|
d_error("No IMSI");
|
|
return NULL;
|
|
}
|
|
|
|
if (req->access_point_name.presence == 0)
|
|
{
|
|
d_error("No APN");
|
|
return NULL;
|
|
}
|
|
|
|
apn_parse(apn, req->access_point_name.data, req->access_point_name.len);
|
|
sess = sgw_sess_find_by_imsi_apn(req->imsi.data, req->imsi.len, apn);
|
|
if (!sess)
|
|
{
|
|
sess = sgw_sess_add(req->imsi.data, req->imsi.len, apn,
|
|
req->bearer_contexts_to_be_created.eps_bearer_id.u8);
|
|
d_assert(sess, return NULL, "No Session Context");
|
|
}
|
|
|
|
return sess;
|
|
}
|
|
|
|
hash_index_t* sgw_sess_first()
|
|
{
|
|
d_assert(self.sess_hash, return NULL, "Null param");
|
|
return hash_first(self.sess_hash);
|
|
}
|
|
|
|
hash_index_t* sgw_sess_next(hash_index_t *hi)
|
|
{
|
|
return hash_next(hi);
|
|
}
|
|
|
|
sgw_sess_t *sgw_sess_this(hash_index_t *hi)
|
|
{
|
|
d_assert(hi, return NULL, "Null param");
|
|
return hash_this_val(hi);
|
|
}
|
|
|
|
|
|
sgw_bearer_t* sgw_bearer_add(sgw_sess_t *sess, c_uint8_t id)
|
|
{
|
|
sgw_bearer_t *bearer = NULL;
|
|
|
|
d_assert(sess, return NULL, "Null param");
|
|
|
|
index_alloc(&sgw_bearer_pool, &bearer);
|
|
d_assert(bearer, return NULL, "Bearer context allocation failed");
|
|
|
|
bearer->id = id;
|
|
bearer->sgw_s1u_teid = bearer->index;
|
|
bearer->sgw_s1u_addr = sgw_self()->s1u_addr;
|
|
bearer->sgw_s5u_teid = bearer->index;
|
|
bearer->sgw_s5u_addr = sgw_self()->s5u_addr;
|
|
|
|
bearer->sess = sess;
|
|
list_append(&sess->bearer_list, bearer);
|
|
|
|
return bearer;
|
|
}
|
|
|
|
status_t sgw_bearer_remove(sgw_bearer_t *bearer)
|
|
{
|
|
int i;
|
|
|
|
d_assert(bearer, return CORE_ERROR, "Null param");
|
|
d_assert(bearer->sess, return CORE_ERROR, "Null param");
|
|
|
|
/* Free the buffered packets */
|
|
for (i = 0; i < bearer->num_buffered_pkt; i++)
|
|
pkbuf_free(bearer->buffered_pkts[i]);
|
|
|
|
list_remove(&bearer->sess->bearer_list, bearer);
|
|
index_free(&sgw_bearer_pool, bearer);
|
|
|
|
return CORE_OK;
|
|
}
|
|
|
|
status_t sgw_bearer_remove_all(sgw_sess_t *sess)
|
|
{
|
|
sgw_bearer_t *bearer = NULL, *next_bearer = NULL;
|
|
|
|
d_assert(sess, return CORE_ERROR, "Null param");
|
|
|
|
bearer = list_first(&sess->bearer_list);
|
|
while (bearer)
|
|
{
|
|
next_bearer = list_next(bearer);
|
|
|
|
sgw_bearer_remove(bearer);
|
|
|
|
bearer = next_bearer;
|
|
}
|
|
|
|
return CORE_OK;
|
|
}
|
|
|
|
sgw_bearer_t* sgw_bearer_find(index_t index)
|
|
{
|
|
d_assert(index && index < MAX_NUM_OF_UE_BEARER, return NULL,
|
|
"Invalid Index(%d)",index);
|
|
|
|
return index_find(&sgw_bearer_pool, index);
|
|
}
|
|
|
|
sgw_bearer_t* sgw_bearer_find_by_sgw_s5u_teid(c_uint32_t sgw_s5u_teid)
|
|
{
|
|
return sgw_bearer_find(sgw_s5u_teid);
|
|
}
|
|
|
|
sgw_bearer_t* sgw_bearer_find_by_sgw_s1u_teid(c_uint32_t sgw_s1u_teid)
|
|
{
|
|
return sgw_bearer_find(sgw_s1u_teid);
|
|
}
|
|
|
|
sgw_bearer_t* sgw_bearer_find_by_id(sgw_sess_t *sess, c_uint8_t id)
|
|
{
|
|
sgw_bearer_t *bearer = NULL;
|
|
|
|
d_assert(sess, return NULL, "Null param");
|
|
|
|
bearer = list_first(&sess->bearer_list);
|
|
while (bearer)
|
|
{
|
|
if (bearer->id == id)
|
|
break;
|
|
|
|
bearer = list_next(bearer);
|
|
}
|
|
|
|
return bearer;
|
|
}
|
|
|
|
sgw_bearer_t* sgw_default_bearer_in_sess(sgw_sess_t *sess)
|
|
{
|
|
return sgw_bearer_first(sess);
|
|
}
|
|
|
|
sgw_bearer_t* sgw_bearer_first(sgw_sess_t *sess)
|
|
{
|
|
d_assert(sess, return NULL, "Null param");
|
|
return list_first(&sess->bearer_list);
|
|
}
|
|
|
|
sgw_bearer_t* sgw_bearer_next(sgw_bearer_t *bearer)
|
|
{
|
|
return list_next(bearer);
|
|
}
|
|
|