1 /* $FreeBSD$ */ 2 /*- 3 * Copyright (c) 2008 Hans Petter Selasky. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/stdint.h> 28 #include <sys/stddef.h> 29 #include <sys/param.h> 30 #include <sys/queue.h> 31 #include <sys/types.h> 32 #include <sys/systm.h> 33 #include <sys/kernel.h> 34 #include <sys/bus.h> 35 #include <sys/module.h> 36 #include <sys/lock.h> 37 #include <sys/mutex.h> 38 #include <sys/condvar.h> 39 #include <sys/sysctl.h> 40 #include <sys/sx.h> 41 #include <sys/unistd.h> 42 #include <sys/callout.h> 43 #include <sys/malloc.h> 44 #include <sys/priv.h> 45 46 #include <dev/usb/usb.h> 47 #include <dev/usb/usbdi.h> 48 #include <dev/usb/usbdi_util.h> 49 50 51 /*------------------------------------------------------------------------* 52 * usb_desc_foreach 53 * 54 * This function is the safe way to iterate across the USB config 55 * descriptor. It contains several checks against invalid 56 * descriptors. If the "desc" argument passed to this function is 57 * "NULL" the first descriptor, if any, will be returned. 58 * 59 * Return values: 60 * NULL: End of descriptors 61 * Else: Next descriptor after "desc" 62 *------------------------------------------------------------------------*/ 63 struct usb_descriptor * 64 usb_desc_foreach(struct usb_config_descriptor *cd, 65 struct usb_descriptor *_desc) 66 { 67 uint8_t *desc_next; 68 uint8_t *start; 69 uint8_t *end; 70 uint8_t *desc; 71 72 /* be NULL safe */ 73 if (cd == NULL) 74 return (NULL); 75 76 /* We assume that the "wTotalLength" has been checked. */ 77 start = (uint8_t *)cd; 78 end = start + UGETW(cd->wTotalLength); 79 desc = (uint8_t *)_desc; 80 81 /* Get start of next USB descriptor. */ 82 if (desc == NULL) 83 desc = start; 84 else 85 desc = desc + desc[0]; 86 87 /* Check that the next USB descriptor is within the range. */ 88 if ((desc < start) || (desc >= end)) 89 return (NULL); /* out of range, or EOD */ 90 91 /* Check that the second next USB descriptor is within range. */ 92 desc_next = desc + desc[0]; 93 if ((desc_next < start) || (desc_next > end)) 94 return (NULL); /* out of range */ 95 96 /* Check minimum descriptor length. */ 97 if (desc[0] < 3) 98 return (NULL); /* too short descriptor */ 99 100 /* Return start of next descriptor. */ 101 return ((struct usb_descriptor *)desc); 102 } 103 104 /*------------------------------------------------------------------------* 105 * usb_idesc_foreach 106 * 107 * This function will iterate the interface descriptors in the config 108 * descriptor. The parse state structure should be zeroed before 109 * calling this function the first time. 110 * 111 * Return values: 112 * NULL: End of descriptors 113 * Else: A valid interface descriptor 114 *------------------------------------------------------------------------*/ 115 struct usb_interface_descriptor * 116 usb_idesc_foreach(struct usb_config_descriptor *cd, 117 struct usb_idesc_parse_state *ps) 118 { 119 struct usb_interface_descriptor *id; 120 uint8_t new_iface; 121 122 /* retrieve current descriptor */ 123 id = (struct usb_interface_descriptor *)ps->desc; 124 /* default is to start a new interface */ 125 new_iface = 1; 126 127 while (1) { 128 id = (struct usb_interface_descriptor *) 129 usb_desc_foreach(cd, (struct usb_descriptor *)id); 130 if (id == NULL) 131 break; 132 if ((id->bDescriptorType == UDESC_INTERFACE) && 133 (id->bLength >= sizeof(*id))) { 134 if (ps->iface_no_last == id->bInterfaceNumber) 135 new_iface = 0; 136 ps->iface_no_last = id->bInterfaceNumber; 137 break; 138 } 139 } 140 141 if (ps->desc == NULL) { 142 /* first time */ 143 } else if (new_iface) { 144 /* new interface */ 145 ps->iface_index ++; 146 ps->iface_index_alt = 0; 147 } else { 148 /* new alternate interface */ 149 ps->iface_index_alt ++; 150 } 151 152 /* store and return current descriptor */ 153 ps->desc = (struct usb_descriptor *)id; 154 return (id); 155 } 156 157 /*------------------------------------------------------------------------* 158 * usb_edesc_foreach 159 * 160 * This function will iterate all the endpoint descriptors within an 161 * interface descriptor. Starting value for the "ped" argument should 162 * be a valid interface descriptor. 163 * 164 * Return values: 165 * NULL: End of descriptors 166 * Else: A valid endpoint descriptor 167 *------------------------------------------------------------------------*/ 168 struct usb_endpoint_descriptor * 169 usb_edesc_foreach(struct usb_config_descriptor *cd, 170 struct usb_endpoint_descriptor *ped) 171 { 172 struct usb_descriptor *desc; 173 174 desc = ((struct usb_descriptor *)ped); 175 176 while ((desc = usb_desc_foreach(cd, desc))) { 177 if (desc->bDescriptorType == UDESC_INTERFACE) { 178 break; 179 } 180 if (desc->bDescriptorType == UDESC_ENDPOINT) { 181 if (desc->bLength < sizeof(*ped)) { 182 /* endpoint descriptor is invalid */ 183 break; 184 } 185 return ((struct usb_endpoint_descriptor *)desc); 186 } 187 } 188 return (NULL); 189 } 190 191 /*------------------------------------------------------------------------* 192 * usb_ed_comp_foreach 193 * 194 * This function will iterate all the endpoint companion descriptors 195 * within an endpoint descriptor in an interface descriptor. Starting 196 * value for the "ped" argument should be a valid endpoint companion 197 * descriptor. 198 * 199 * Return values: 200 * NULL: End of descriptors 201 * Else: A valid endpoint companion descriptor 202 *------------------------------------------------------------------------*/ 203 struct usb_endpoint_ss_comp_descriptor * 204 usb_ed_comp_foreach(struct usb_config_descriptor *cd, 205 struct usb_endpoint_ss_comp_descriptor *ped) 206 { 207 struct usb_descriptor *desc; 208 209 desc = ((struct usb_descriptor *)ped); 210 211 while ((desc = usb_desc_foreach(cd, desc))) { 212 if (desc->bDescriptorType == UDESC_INTERFACE) 213 break; 214 if (desc->bDescriptorType == UDESC_ENDPOINT) 215 break; 216 if (desc->bDescriptorType == UDESC_ENDPOINT_SS_COMP) { 217 if (desc->bLength < sizeof(*ped)) { 218 /* endpoint companion descriptor is invalid */ 219 break; 220 } 221 return ((struct usb_endpoint_ss_comp_descriptor *)desc); 222 } 223 } 224 return (NULL); 225 } 226 227 /*------------------------------------------------------------------------* 228 * usbd_get_no_descriptors 229 * 230 * This function will count the total number of descriptors in the 231 * configuration descriptor of type "type". 232 *------------------------------------------------------------------------*/ 233 uint8_t 234 usbd_get_no_descriptors(struct usb_config_descriptor *cd, uint8_t type) 235 { 236 struct usb_descriptor *desc = NULL; 237 uint8_t count = 0; 238 239 while ((desc = usb_desc_foreach(cd, desc))) { 240 if (desc->bDescriptorType == type) { 241 count++; 242 if (count == 0xFF) 243 break; /* crazy */ 244 } 245 } 246 return (count); 247 } 248 249 /*------------------------------------------------------------------------* 250 * usbd_get_no_alts 251 * 252 * Return value: 253 * Number of alternate settings for the given interface descriptor 254 * pointer. If the USB descriptor is corrupt, the returned value can 255 * be greater than the actual number of alternate settings. 256 *------------------------------------------------------------------------*/ 257 uint8_t 258 usbd_get_no_alts(struct usb_config_descriptor *cd, 259 struct usb_interface_descriptor *id) 260 { 261 struct usb_descriptor *desc; 262 uint8_t n; 263 uint8_t ifaceno; 264 265 /* Reset interface count */ 266 267 n = 0; 268 269 /* Get the interface number */ 270 271 ifaceno = id->bInterfaceNumber; 272 273 /* Iterate all the USB descriptors */ 274 275 desc = NULL; 276 while ((desc = usb_desc_foreach(cd, desc))) { 277 if ((desc->bDescriptorType == UDESC_INTERFACE) && 278 (desc->bLength >= sizeof(*id))) { 279 id = (struct usb_interface_descriptor *)desc; 280 if (id->bInterfaceNumber == ifaceno) { 281 n++; 282 if (n == 0xFF) 283 break; /* crazy */ 284 } 285 } 286 } 287 return (n); 288 } 289