1 /* 2 * net/dccp/ccid.c 3 * 4 * An implementation of the DCCP protocol 5 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 6 * 7 * CCID infrastructure 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 */ 13 14 #include "ccid.h" 15 #include "ccids/lib/tfrc.h" 16 17 static struct ccid_operations *ccids[] = { 18 &ccid2_ops, 19 #ifdef CONFIG_IP_DCCP_CCID3 20 &ccid3_ops, 21 #endif 22 }; 23 24 static struct ccid_operations *ccid_by_number(const u8 id) 25 { 26 int i; 27 28 for (i = 0; i < ARRAY_SIZE(ccids); i++) 29 if (ccids[i]->ccid_id == id) 30 return ccids[i]; 31 return NULL; 32 } 33 34 /* check that up to @array_len members in @ccid_array are supported */ 35 bool ccid_support_check(u8 const *ccid_array, u8 array_len) 36 { 37 while (array_len > 0) 38 if (ccid_by_number(ccid_array[--array_len]) == NULL) 39 return false; 40 return true; 41 } 42 43 /** 44 * ccid_get_builtin_ccids - Populate a list of built-in CCIDs 45 * @ccid_array: pointer to copy into 46 * @array_len: value to return length into 47 * This function allocates memory - caller must see that it is freed after use. 48 */ 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 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 (len < ARRAY_SIZE(ccids)) 67 return -EINVAL; 68 69 if (ccid_get_builtin_ccids(&ccid_array, &array_len)) 70 return -ENOBUFS; 71 72 if (put_user(array_len, optlen) || 73 copy_to_user(optval, ccid_array, array_len)) 74 err = -EFAULT; 75 76 kfree(ccid_array); 77 return err; 78 } 79 80 static struct kmem_cache *ccid_kmem_cache_create(int obj_size, const char *fmt,...) 81 { 82 struct kmem_cache *slab; 83 char slab_name_fmt[32], *slab_name; 84 va_list args; 85 86 va_start(args, fmt); 87 vsnprintf(slab_name_fmt, sizeof(slab_name_fmt), fmt, args); 88 va_end(args); 89 90 slab_name = kstrdup(slab_name_fmt, GFP_KERNEL); 91 if (slab_name == NULL) 92 return NULL; 93 slab = kmem_cache_create(slab_name, sizeof(struct ccid) + obj_size, 0, 94 SLAB_HWCACHE_ALIGN, NULL); 95 if (slab == NULL) 96 kfree(slab_name); 97 return slab; 98 } 99 100 static void ccid_kmem_cache_destroy(struct kmem_cache *slab) 101 { 102 if (slab != NULL) { 103 const char *name = kmem_cache_name(slab); 104 105 kmem_cache_destroy(slab); 106 kfree(name); 107 } 108 } 109 110 static int ccid_activate(struct ccid_operations *ccid_ops) 111 { 112 int err = -ENOBUFS; 113 114 ccid_ops->ccid_hc_rx_slab = 115 ccid_kmem_cache_create(ccid_ops->ccid_hc_rx_obj_size, 116 "ccid%u_hc_rx_sock", 117 ccid_ops->ccid_id); 118 if (ccid_ops->ccid_hc_rx_slab == NULL) 119 goto out; 120 121 ccid_ops->ccid_hc_tx_slab = 122 ccid_kmem_cache_create(ccid_ops->ccid_hc_tx_obj_size, 123 "ccid%u_hc_tx_sock", 124 ccid_ops->ccid_id); 125 if (ccid_ops->ccid_hc_tx_slab == NULL) 126 goto out_free_rx_slab; 127 128 pr_info("CCID: Activated CCID %d (%s)\n", 129 ccid_ops->ccid_id, ccid_ops->ccid_name); 130 err = 0; 131 out: 132 return err; 133 out_free_rx_slab: 134 ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab); 135 ccid_ops->ccid_hc_rx_slab = NULL; 136 goto out; 137 } 138 139 static void ccid_deactivate(struct ccid_operations *ccid_ops) 140 { 141 ccid_kmem_cache_destroy(ccid_ops->ccid_hc_tx_slab); 142 ccid_ops->ccid_hc_tx_slab = NULL; 143 ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab); 144 ccid_ops->ccid_hc_rx_slab = NULL; 145 146 pr_info("CCID: Deactivated CCID %d (%s)\n", 147 ccid_ops->ccid_id, ccid_ops->ccid_name); 148 } 149 150 struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx) 151 { 152 struct ccid_operations *ccid_ops = ccid_by_number(id); 153 struct ccid *ccid = NULL; 154 155 if (ccid_ops == NULL) 156 goto out; 157 158 ccid = kmem_cache_alloc(rx ? ccid_ops->ccid_hc_rx_slab : 159 ccid_ops->ccid_hc_tx_slab, gfp_any()); 160 if (ccid == NULL) 161 goto out; 162 ccid->ccid_ops = ccid_ops; 163 if (rx) { 164 memset(ccid + 1, 0, ccid_ops->ccid_hc_rx_obj_size); 165 if (ccid->ccid_ops->ccid_hc_rx_init != NULL && 166 ccid->ccid_ops->ccid_hc_rx_init(ccid, sk) != 0) 167 goto out_free_ccid; 168 } else { 169 memset(ccid + 1, 0, ccid_ops->ccid_hc_tx_obj_size); 170 if (ccid->ccid_ops->ccid_hc_tx_init != NULL && 171 ccid->ccid_ops->ccid_hc_tx_init(ccid, sk) != 0) 172 goto out_free_ccid; 173 } 174 out: 175 return ccid; 176 out_free_ccid: 177 kmem_cache_free(rx ? ccid_ops->ccid_hc_rx_slab : 178 ccid_ops->ccid_hc_tx_slab, ccid); 179 ccid = NULL; 180 goto out; 181 } 182 183 void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk) 184 { 185 if (ccid != NULL) { 186 if (ccid->ccid_ops->ccid_hc_rx_exit != NULL) 187 ccid->ccid_ops->ccid_hc_rx_exit(sk); 188 kmem_cache_free(ccid->ccid_ops->ccid_hc_rx_slab, ccid); 189 } 190 } 191 192 void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk) 193 { 194 if (ccid != NULL) { 195 if (ccid->ccid_ops->ccid_hc_tx_exit != NULL) 196 ccid->ccid_ops->ccid_hc_tx_exit(sk); 197 kmem_cache_free(ccid->ccid_ops->ccid_hc_tx_slab, ccid); 198 } 199 } 200 201 int __init ccid_initialize_builtins(void) 202 { 203 int i, err = tfrc_lib_init(); 204 205 if (err) 206 return err; 207 208 for (i = 0; i < ARRAY_SIZE(ccids); i++) { 209 err = ccid_activate(ccids[i]); 210 if (err) 211 goto unwind_registrations; 212 } 213 return 0; 214 215 unwind_registrations: 216 while(--i >= 0) 217 ccid_deactivate(ccids[i]); 218 tfrc_lib_exit(); 219 return err; 220 } 221 222 void ccid_cleanup_builtins(void) 223 { 224 int i; 225 226 for (i = 0; i < ARRAY_SIZE(ccids); i++) 227 ccid_deactivate(ccids[i]); 228 tfrc_lib_exit(); 229 } 230