1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * net/dccp/ccid.c 4 * 5 * An implementation of the DCCP protocol 6 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 7 * 8 * CCID infrastructure 9 */ 10 11 #include <linux/slab.h> 12 13 #include "ccid.h" 14 #include "ccids/lib/tfrc.h" 15 16 static struct ccid_operations *ccids[] = { 17 &ccid2_ops, 18 #ifdef CONFIG_IP_DCCP_CCID3 19 &ccid3_ops, 20 #endif 21 }; 22 ccid_by_number(const u8 id)23 static struct ccid_operations *ccid_by_number(const u8 id) 24 { 25 int i; 26 27 for (i = 0; i < ARRAY_SIZE(ccids); i++) 28 if (ccids[i]->ccid_id == id) 29 return ccids[i]; 30 return NULL; 31 } 32 33 /* check that up to @array_len members in @ccid_array are supported */ ccid_support_check(u8 const * ccid_array,u8 array_len)34 bool ccid_support_check(u8 const *ccid_array, u8 array_len) 35 { 36 while (array_len > 0) 37 if (ccid_by_number(ccid_array[--array_len]) == NULL) 38 return false; 39 return true; 40 } 41 42 /** 43 * ccid_get_builtin_ccids - Populate a list of built-in CCIDs 44 * @ccid_array: pointer to copy into 45 * @array_len: value to return length into 46 * 47 * This function allocates memory - caller must see that it is freed after use. 48 */ ccid_get_builtin_ccids(u8 ** ccid_array,u8 * array_len)49 int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len) 50 { 51 *ccid_array = kmalloc(ARRAY_SIZE(ccids), gfp_any()); 52 if (*ccid_array == NULL) 53 return -ENOBUFS; 54 55 for (*array_len = 0; *array_len < ARRAY_SIZE(ccids); *array_len += 1) 56 (*ccid_array)[*array_len] = ccids[*array_len]->ccid_id; 57 return 0; 58 } 59 ccid_getsockopt_builtin_ccids(struct sock * sk,int len,char __user * optval,int __user * optlen)60 int ccid_getsockopt_builtin_ccids(struct sock *sk, int len, 61 char __user *optval, int __user *optlen) 62 { 63 u8 *ccid_array, array_len; 64 int err = 0; 65 66 if (ccid_get_builtin_ccids(&ccid_array, &array_len)) 67 return -ENOBUFS; 68 69 if (put_user(array_len, optlen)) 70 err = -EFAULT; 71 else if (len > 0 && copy_to_user(optval, ccid_array, 72 len > array_len ? array_len : len)) 73 err = -EFAULT; 74 75 kfree(ccid_array); 76 return err; 77 } 78 ccid_kmem_cache_create(int obj_size,char * slab_name_fmt,const char * fmt,...)79 static __printf(3, 4) struct kmem_cache *ccid_kmem_cache_create(int obj_size, char *slab_name_fmt, const char *fmt,...) 80 { 81 struct kmem_cache *slab; 82 va_list args; 83 84 va_start(args, fmt); 85 vsnprintf(slab_name_fmt, CCID_SLAB_NAME_LENGTH, fmt, args); 86 va_end(args); 87 88 slab = kmem_cache_create(slab_name_fmt, sizeof(struct ccid) + obj_size, 0, 89 SLAB_HWCACHE_ALIGN, NULL); 90 return slab; 91 } 92 ccid_kmem_cache_destroy(struct kmem_cache * slab)93 static void ccid_kmem_cache_destroy(struct kmem_cache *slab) 94 { 95 kmem_cache_destroy(slab); 96 } 97 ccid_activate(struct ccid_operations * ccid_ops)98 static int __init ccid_activate(struct ccid_operations *ccid_ops) 99 { 100 int err = -ENOBUFS; 101 102 ccid_ops->ccid_hc_rx_slab = 103 ccid_kmem_cache_create(ccid_ops->ccid_hc_rx_obj_size, 104 ccid_ops->ccid_hc_rx_slab_name, 105 "ccid%u_hc_rx_sock", 106 ccid_ops->ccid_id); 107 if (ccid_ops->ccid_hc_rx_slab == NULL) 108 goto out; 109 110 ccid_ops->ccid_hc_tx_slab = 111 ccid_kmem_cache_create(ccid_ops->ccid_hc_tx_obj_size, 112 ccid_ops->ccid_hc_tx_slab_name, 113 "ccid%u_hc_tx_sock", 114 ccid_ops->ccid_id); 115 if (ccid_ops->ccid_hc_tx_slab == NULL) 116 goto out_free_rx_slab; 117 118 pr_info("DCCP: Activated CCID %d (%s)\n", 119 ccid_ops->ccid_id, ccid_ops->ccid_name); 120 err = 0; 121 out: 122 return err; 123 out_free_rx_slab: 124 ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab); 125 ccid_ops->ccid_hc_rx_slab = NULL; 126 goto out; 127 } 128 ccid_deactivate(struct ccid_operations * ccid_ops)129 static void ccid_deactivate(struct ccid_operations *ccid_ops) 130 { 131 ccid_kmem_cache_destroy(ccid_ops->ccid_hc_tx_slab); 132 ccid_ops->ccid_hc_tx_slab = NULL; 133 ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab); 134 ccid_ops->ccid_hc_rx_slab = NULL; 135 136 pr_info("DCCP: Deactivated CCID %d (%s)\n", 137 ccid_ops->ccid_id, ccid_ops->ccid_name); 138 } 139 ccid_new(const u8 id,struct sock * sk,bool rx)140 struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx) 141 { 142 struct ccid_operations *ccid_ops = ccid_by_number(id); 143 struct ccid *ccid = NULL; 144 145 if (ccid_ops == NULL) 146 goto out; 147 148 ccid = kmem_cache_alloc(rx ? ccid_ops->ccid_hc_rx_slab : 149 ccid_ops->ccid_hc_tx_slab, gfp_any()); 150 if (ccid == NULL) 151 goto out; 152 ccid->ccid_ops = ccid_ops; 153 if (rx) { 154 memset(ccid + 1, 0, ccid_ops->ccid_hc_rx_obj_size); 155 if (ccid->ccid_ops->ccid_hc_rx_init != NULL && 156 ccid->ccid_ops->ccid_hc_rx_init(ccid, sk) != 0) 157 goto out_free_ccid; 158 } else { 159 memset(ccid + 1, 0, ccid_ops->ccid_hc_tx_obj_size); 160 if (ccid->ccid_ops->ccid_hc_tx_init != NULL && 161 ccid->ccid_ops->ccid_hc_tx_init(ccid, sk) != 0) 162 goto out_free_ccid; 163 } 164 out: 165 return ccid; 166 out_free_ccid: 167 kmem_cache_free(rx ? ccid_ops->ccid_hc_rx_slab : 168 ccid_ops->ccid_hc_tx_slab, ccid); 169 ccid = NULL; 170 goto out; 171 } 172 ccid_hc_rx_delete(struct ccid * ccid,struct sock * sk)173 void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk) 174 { 175 if (ccid != NULL) { 176 if (ccid->ccid_ops->ccid_hc_rx_exit != NULL) 177 ccid->ccid_ops->ccid_hc_rx_exit(sk); 178 kmem_cache_free(ccid->ccid_ops->ccid_hc_rx_slab, ccid); 179 } 180 } 181 ccid_hc_tx_delete(struct ccid * ccid,struct sock * sk)182 void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk) 183 { 184 if (ccid != NULL) { 185 if (ccid->ccid_ops->ccid_hc_tx_exit != NULL) 186 ccid->ccid_ops->ccid_hc_tx_exit(sk); 187 kmem_cache_free(ccid->ccid_ops->ccid_hc_tx_slab, ccid); 188 } 189 } 190 ccid_initialize_builtins(void)191 int __init ccid_initialize_builtins(void) 192 { 193 int i, err = tfrc_lib_init(); 194 195 if (err) 196 return err; 197 198 for (i = 0; i < ARRAY_SIZE(ccids); i++) { 199 err = ccid_activate(ccids[i]); 200 if (err) 201 goto unwind_registrations; 202 } 203 return 0; 204 205 unwind_registrations: 206 while(--i >= 0) 207 ccid_deactivate(ccids[i]); 208 tfrc_lib_exit(); 209 return err; 210 } 211 ccid_cleanup_builtins(void)212 void ccid_cleanup_builtins(void) 213 { 214 int i; 215 216 for (i = 0; i < ARRAY_SIZE(ccids); i++) 217 ccid_deactivate(ccids[i]); 218 tfrc_lib_exit(); 219 } 220