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 #ifdef USB_GLOBAL_INCLUDE_FILE 28 #include USB_GLOBAL_INCLUDE_FILE 29 #else 30 #include <sys/stdint.h> 31 #include <sys/stddef.h> 32 #include <sys/param.h> 33 #include <sys/queue.h> 34 #include <sys/types.h> 35 #include <sys/systm.h> 36 #include <sys/kernel.h> 37 #include <sys/bus.h> 38 #include <sys/module.h> 39 #include <sys/lock.h> 40 #include <sys/mutex.h> 41 #include <sys/condvar.h> 42 #include <sys/sysctl.h> 43 #include <sys/sx.h> 44 #include <sys/unistd.h> 45 #include <sys/callout.h> 46 #include <sys/malloc.h> 47 #include <sys/priv.h> 48 49 #include <dev/usb/usb.h> 50 #include <dev/usb/usbdi.h> 51 #include <dev/usb/usbdi_util.h> 52 53 #define USB_DEBUG_VAR usb_debug 54 55 #include <dev/usb/usb_core.h> 56 #include <dev/usb/usb_debug.h> 57 #endif /* USB_GLOBAL_INCLUDE_FILE */ 58 59 /*------------------------------------------------------------------------* 60 * usb_desc_foreach 61 * 62 * This function is the safe way to iterate across the USB config 63 * descriptor. It contains several checks against invalid 64 * descriptors. If the "desc" argument passed to this function is 65 * "NULL" the first descriptor, if any, will be returned. 66 * 67 * Return values: 68 * NULL: End of descriptors 69 * Else: Next descriptor after "desc" 70 *------------------------------------------------------------------------*/ 71 struct usb_descriptor * 72 usb_desc_foreach(struct usb_config_descriptor *cd, 73 struct usb_descriptor *_desc) 74 { 75 uint8_t *desc_next; 76 uint8_t *start; 77 uint8_t *end; 78 uint8_t *desc; 79 80 /* be NULL safe */ 81 if (cd == NULL) 82 return (NULL); 83 84 /* We assume that the "wTotalLength" has been checked. */ 85 start = (uint8_t *)cd; 86 end = start + UGETW(cd->wTotalLength); 87 desc = (uint8_t *)_desc; 88 89 /* Get start of next USB descriptor. */ 90 if (desc == NULL) 91 desc = start; 92 else 93 desc = desc + desc[0]; 94 95 /* Check that the next USB descriptor is within the range. */ 96 if ((desc < start) || (desc >= end)) 97 return (NULL); /* out of range, or EOD */ 98 99 /* Check that the second next USB descriptor is within range. */ 100 desc_next = desc + desc[0]; 101 if ((desc_next < start) || (desc_next > end)) 102 return (NULL); /* out of range */ 103 104 /* Check minimum descriptor length. */ 105 if (desc[0] < 3) 106 return (NULL); /* too short descriptor */ 107 108 /* Return start of next descriptor. */ 109 return ((struct usb_descriptor *)desc); 110 } 111 112 /*------------------------------------------------------------------------* 113 * usb_idesc_foreach 114 * 115 * This function will iterate the interface descriptors in the config 116 * descriptor. The parse state structure should be zeroed before 117 * calling this function the first time. 118 * 119 * Return values: 120 * NULL: End of descriptors 121 * Else: A valid interface descriptor 122 *------------------------------------------------------------------------*/ 123 struct usb_interface_descriptor * 124 usb_idesc_foreach(struct usb_config_descriptor *cd, 125 struct usb_idesc_parse_state *ps) 126 { 127 struct usb_interface_descriptor *id; 128 uint8_t new_iface; 129 130 /* retrieve current descriptor */ 131 id = (struct usb_interface_descriptor *)ps->desc; 132 /* default is to start a new interface */ 133 new_iface = 1; 134 135 while (1) { 136 id = (struct usb_interface_descriptor *) 137 usb_desc_foreach(cd, (struct usb_descriptor *)id); 138 if (id == NULL) 139 break; 140 if ((id->bDescriptorType == UDESC_INTERFACE) && 141 (id->bLength >= sizeof(*id))) { 142 if (ps->iface_no_last == id->bInterfaceNumber) 143 new_iface = 0; 144 ps->iface_no_last = id->bInterfaceNumber; 145 break; 146 } 147 } 148 149 if (ps->desc == NULL) { 150 /* first time or zero descriptors */ 151 } else if (new_iface) { 152 /* new interface */ 153 ps->iface_index ++; 154 ps->iface_index_alt = 0; 155 } else { 156 /* new alternate interface */ 157 ps->iface_index_alt ++; 158 } 159 #if (USB_IFACE_MAX <= 0) 160 #error "USB_IFACE_MAX must be defined greater than zero" 161 #endif 162 /* check for too many interfaces */ 163 if (ps->iface_index >= USB_IFACE_MAX) { 164 DPRINTF("Interface limit reached\n"); 165 id = NULL; 166 } 167 168 /* store and return current descriptor */ 169 ps->desc = (struct usb_descriptor *)id; 170 return (id); 171 } 172 173 /*------------------------------------------------------------------------* 174 * usb_edesc_foreach 175 * 176 * This function will iterate all the endpoint descriptors within an 177 * interface descriptor. Starting value for the "ped" argument should 178 * be a valid interface descriptor. 179 * 180 * Return values: 181 * NULL: End of descriptors 182 * Else: A valid endpoint descriptor 183 *------------------------------------------------------------------------*/ 184 struct usb_endpoint_descriptor * 185 usb_edesc_foreach(struct usb_config_descriptor *cd, 186 struct usb_endpoint_descriptor *ped) 187 { 188 struct usb_descriptor *desc; 189 190 desc = ((struct usb_descriptor *)ped); 191 192 while ((desc = usb_desc_foreach(cd, desc))) { 193 if (desc->bDescriptorType == UDESC_INTERFACE) { 194 break; 195 } 196 if (desc->bDescriptorType == UDESC_ENDPOINT) { 197 if (desc->bLength < sizeof(*ped)) { 198 /* endpoint descriptor is invalid */ 199 break; 200 } 201 return ((struct usb_endpoint_descriptor *)desc); 202 } 203 } 204 return (NULL); 205 } 206 207 /*------------------------------------------------------------------------* 208 * usb_ed_comp_foreach 209 * 210 * This function will iterate all the endpoint companion descriptors 211 * within an endpoint descriptor in an interface descriptor. Starting 212 * value for the "ped" argument should be a valid endpoint companion 213 * descriptor. 214 * 215 * Return values: 216 * NULL: End of descriptors 217 * Else: A valid endpoint companion descriptor 218 *------------------------------------------------------------------------*/ 219 struct usb_endpoint_ss_comp_descriptor * 220 usb_ed_comp_foreach(struct usb_config_descriptor *cd, 221 struct usb_endpoint_ss_comp_descriptor *ped) 222 { 223 struct usb_descriptor *desc; 224 225 desc = ((struct usb_descriptor *)ped); 226 227 while ((desc = usb_desc_foreach(cd, desc))) { 228 if (desc->bDescriptorType == UDESC_INTERFACE) 229 break; 230 if (desc->bDescriptorType == UDESC_ENDPOINT) 231 break; 232 if (desc->bDescriptorType == UDESC_ENDPOINT_SS_COMP) { 233 if (desc->bLength < sizeof(*ped)) { 234 /* endpoint companion descriptor is invalid */ 235 break; 236 } 237 return ((struct usb_endpoint_ss_comp_descriptor *)desc); 238 } 239 } 240 return (NULL); 241 } 242 243 /*------------------------------------------------------------------------* 244 * usbd_get_no_descriptors 245 * 246 * This function will count the total number of descriptors in the 247 * configuration descriptor of type "type". 248 *------------------------------------------------------------------------*/ 249 uint8_t 250 usbd_get_no_descriptors(struct usb_config_descriptor *cd, uint8_t type) 251 { 252 struct usb_descriptor *desc = NULL; 253 uint8_t count = 0; 254 255 while ((desc = usb_desc_foreach(cd, desc))) { 256 if (desc->bDescriptorType == type) { 257 count++; 258 if (count == 0xFF) 259 break; /* crazy */ 260 } 261 } 262 return (count); 263 } 264 265 /*------------------------------------------------------------------------* 266 * usbd_get_no_alts 267 * 268 * Return value: 269 * Number of alternate settings for the given interface descriptor 270 * pointer. If the USB descriptor is corrupt, the returned value can 271 * be greater than the actual number of alternate settings. 272 *------------------------------------------------------------------------*/ 273 uint8_t 274 usbd_get_no_alts(struct usb_config_descriptor *cd, 275 struct usb_interface_descriptor *id) 276 { 277 struct usb_descriptor *desc; 278 uint8_t n; 279 uint8_t ifaceno; 280 281 /* Reset interface count */ 282 283 n = 0; 284 285 /* Get the interface number */ 286 287 ifaceno = id->bInterfaceNumber; 288 289 /* Iterate all the USB descriptors */ 290 291 desc = NULL; 292 while ((desc = usb_desc_foreach(cd, desc))) { 293 if ((desc->bDescriptorType == UDESC_INTERFACE) && 294 (desc->bLength >= sizeof(*id))) { 295 id = (struct usb_interface_descriptor *)desc; 296 if (id->bInterfaceNumber == ifaceno) { 297 n++; 298 if (n == 0xFF) 299 break; /* crazy */ 300 } 301 } 302 } 303 return (n); 304 } 305