#include #include #include #include #include #include #include "usb.h" #include "hcd.h" #define USB_MAXALTSETTING 128 /* Hard limit */ #define USB_MAXENDPOINTS 30 /* Hard limit */ #define USB_MAXCONFIG 8 /* Arbitrary limit */ static inline const char *plural(int n) { return (n == 1 ? "" : "s"); } static int find_next_descriptor(unsigned char *buffer, int size, int dt1, int dt2, int *num_skipped) { struct usb_descriptor_header *h; int n = 0; unsigned char *buffer0 = buffer; /* Find the next descriptor of type dt1 or dt2 */ while (size > 0) { h = (struct usb_descriptor_header *) buffer; if (h->bDescriptorType == dt1 || h->bDescriptorType == dt2) break; buffer += h->bLength; size -= h->bLength; ++n; } /* Store the number of descriptors skipped and return the * number of bytes skipped */ if (num_skipped) *num_skipped = n; return buffer - buffer0; } static int usb_parse_endpoint(struct device *ddev, int cfgno, int inum, int asnum, struct usb_host_interface *ifp, int num_ep, unsigned char *buffer, int size) { unsigned char *buffer0 = buffer; struct usb_endpoint_descriptor *d; struct usb_host_endpoint *endpoint; int n, i; d = (struct usb_endpoint_descriptor *) buffer; buffer += d->bLength; size -= d->bLength; if (d->bLength >= USB_DT_ENDPOINT_AUDIO_SIZE) n = USB_DT_ENDPOINT_AUDIO_SIZE; else if (d->bLength >= USB_DT_ENDPOINT_SIZE) n = USB_DT_ENDPOINT_SIZE; else { dev_warn(ddev, "config %d interface %d altsetting %d has an " "invalid endpoint descriptor of length %d, skipping\n", cfgno, inum, asnum, d->bLength); goto skip_to_next_endpoint_or_interface_descriptor; } i = d->bEndpointAddress & ~USB_ENDPOINT_DIR_MASK; if (i >= 16 || i == 0) { dev_warn(ddev, "config %d interface %d altsetting %d has an " "invalid endpoint with address 0x%X, skipping\n", cfgno, inum, asnum, d->bEndpointAddress); goto skip_to_next_endpoint_or_interface_descriptor; } /* Only store as many endpoints as we have room for */ if (ifp->desc.bNumEndpoints >= num_ep) goto skip_to_next_endpoint_or_interface_descriptor; endpoint = &ifp->endpoint[ifp->desc.bNumEndpoints]; ++ifp->desc.bNumEndpoints; memcpy(&endpoint->desc, d, n); INIT_LIST_HEAD(&endpoint->urb_list); /* Skip over any Class Specific or Vendor Specific descriptors; * find the next endpoint or interface descriptor */ endpoint->extra = buffer; i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT, USB_DT_INTERFACE, &n); endpoint->extralen = i; if (n > 0) dev_dbg(ddev, "skipped %d descriptor%s after %s\n", n, plural(n), "endpoint"); return buffer - buffer0 + i; skip_to_next_endpoint_or_interface_descriptor: i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT, USB_DT_INTERFACE, NULL); return buffer - buffer0 + i; } void usb_release_interface_cache(struct kref *ref) { struct usb_interface_cache *intfc = ref_to_usb_interface_cache(ref); int j; for (j = 0; j < intfc->num_altsetting; j++) { struct usb_host_interface *alt = &intfc->altsetting[j]; kfree(alt->endpoint); kfree(alt->string); } kfree(intfc); } static int usb_parse_interface(struct device *ddev, int cfgno, struct usb_host_config *config, unsigned char *buffer, int size, u8 inums[], u8 nalts[]) { unsigned char *buffer0 = buffer; struct usb_interface_descriptor *d; int inum, asnum; struct usb_interface_cache *intfc; struct usb_host_interface *alt; int i, n; int len, retval; int num_ep, num_ep_orig; d = (struct usb_interface_descriptor *) buffer; buffer += d->bLength; size -= d->bLength; if (d->bLength < USB_DT_INTERFACE_SIZE) goto skip_to_next_interface_descriptor; /* Which interface entry is this? */ intfc = NULL; inum = d->bInterfaceNumber; for (i = 0; i < config->desc.bNumInterfaces; ++i) { if (inums[i] == inum) { intfc = config->intf_cache[i]; break; } } if (!intfc || intfc->num_altsetting >= nalts[i]) goto skip_to_next_interface_descriptor; /* Check for duplicate altsetting entries */ asnum = d->bAlternateSetting; for ((i = 0, alt = &intfc->altsetting[0]); i < intfc->num_altsetting; (++i, ++alt)) { if (alt->desc.bAlternateSetting == asnum) { dev_warn(ddev, "Duplicate descriptor for config %d " "interface %d altsetting %d, skipping\n", cfgno, inum, asnum); goto skip_to_next_interface_descriptor; } } ++intfc->num_altsetting; memcpy(&alt->desc, d, USB_DT_INTERFACE_SIZE); /* Skip over any Class Specific or Vendor Specific descriptors; * find the first endpoint or interface descriptor */ alt->extra = buffer; i = find_next_descriptor(buffer, size, USB_DT_ENDPOINT, USB_DT_INTERFACE, &n); alt->extralen = i; if (n > 0) dev_dbg(ddev, "skipped %d descriptor%s after %s\n", n, plural(n), "interface"); buffer += i; size -= i; /* Allocate space for the right(?) number of endpoints */ num_ep = num_ep_orig = alt->desc.bNumEndpoints; alt->desc.bNumEndpoints = 0; // Use as a counter if (num_ep > USB_MAXENDPOINTS) { dev_warn(ddev, "too many endpoints for config %d interface %d " "altsetting %d: %d, using maximum allowed: %d\n", cfgno, inum, asnum, num_ep, USB_MAXENDPOINTS); num_ep = USB_MAXENDPOINTS; } len = sizeof(struct usb_host_endpoint) * num_ep; alt->endpoint = kzalloc(len, GFP_KERNEL); if (!alt->endpoint) return -ENOMEM; /* Parse all the endpoint descriptors */ n = 0; while (size > 0) { if (((struct usb_descriptor_header *) buffer)->bDescriptorType == USB_DT_INTERFACE) break; retval = usb_parse_endpoint(ddev, cfgno, inum, asnum, alt, num_ep, buffer, size); if (retval < 0) return retval; ++n; buffer += retval; size -= retval; } if (n != num_ep_orig) dev_warn(ddev, "config %d interface %d altsetting %d has %d " "endpoint descriptor%s, different from the interface " "descriptor's value: %d\n", cfgno, inum, asnum, n, plural(n), num_ep_orig); return buffer - buffer0; skip_to_next_interface_descriptor: i = find_next_descriptor(buffer, size, USB_DT_INTERFACE, USB_DT_INTERFACE, NULL); return buffer - buffer0 + i; } static int usb_parse_configuration(struct device *ddev, int cfgidx, struct usb_host_config *config, unsigned char *buffer, int size) { unsigned char *buffer0 = buffer; int cfgno; int nintf, nintf_orig; int i, j, n; struct usb_interface_cache *intfc; unsigned char *buffer2; int size2; struct usb_descriptor_header *header; int len, retval; u8 inums[USB_MAXINTERFACES], nalts[USB_MAXINTERFACES]; memcpy(&config->desc, buffer, USB_DT_CONFIG_SIZE); if (config->desc.bDescriptorType != USB_DT_CONFIG || config->desc.bLength < USB_DT_CONFIG_SIZE) { dev_err(ddev, "invalid descriptor for config index %d: " "type = 0x%X, length = %d\n", cfgidx, config->desc.bDescriptorType, config->desc.bLength); return -EINVAL; } cfgno = config->desc.bConfigurationValue; buffer += config->desc.bLength; size -= config->desc.bLength; nintf = nintf_orig = config->desc.bNumInterfaces; if (nintf > USB_MAXINTERFACES) { dev_warn(ddev, "config %d has too many interfaces: %d, " "using maximum allowed: %d\n", cfgno, nintf, USB_MAXINTERFACES); nintf = USB_MAXINTERFACES; } /* Go through the descriptors, checking their length and counting the * number of altsettings for each interface */ n = 0; for ((buffer2 = buffer, size2 = size); size2 > 0; (buffer2 += header->bLength, size2 -= header->bLength)) { if (size2 < sizeof(struct usb_descriptor_header)) { dev_warn(ddev, "config %d descriptor has %d excess " "byte%s, ignoring\n", cfgno, size2, plural(size2)); break; } header = (struct usb_descriptor_header *) buffer2; if ((header->bLength > size2) || (header->bLength < 2)) { dev_warn(ddev, "config %d has an invalid descriptor " "of length %d, skipping remainder of the config\n", cfgno, header->bLength); break; } if (header->bDescriptorType == USB_DT_INTERFACE) { struct usb_interface_descriptor *d; int inum; d = (struct usb_interface_descriptor *) header; if (d->bLength < USB_DT_INTERFACE_SIZE) { dev_warn(ddev, "config %d has an invalid " "interface descriptor of length %d, " "skipping\n", cfgno, d->bLength); continue; } inum = d->bInterfaceNumber; if (inum >= nintf_orig) dev_warn(ddev, "config %d has an invalid " "interface number: %d but max is %d\n", cfgno, inum, nintf_orig - 1); /* Have we already encountered this interface? * Count its altsettings */ for (i = 0; i < n; ++i) { if (inums[i] == inum) break; } if (i < n) { if (nalts[i] < 255) ++nalts[i]; } else if (n < USB_MAXINTERFACES) { inums[n] = inum; nalts[n] = 1; ++n; } } else if (header->bDescriptorType == USB_DT_DEVICE || header->bDescriptorType == USB_DT_CONFIG) dev_warn(ddev, "config %d contains an unexpected " "descriptor of type 0x%X, skipping\n", cfgno, header->bDescriptorType); } /* for ((buffer2 = buffer, size2 = size); ...) */ size = buffer2 - buffer; config->desc.wTotalLength = cpu_to_le16(buffer2 - buffer0); if (n != nintf) dev_warn(ddev, "config %d has %d interface%s, different from " "the descriptor's value: %d\n", cfgno, n, plural(n), nintf_orig); else if (n == 0) dev_warn(ddev, "config %d has no interfaces?\n", cfgno); config->desc.bNumInterfaces = nintf = n; /* Check for missing interface numbers */ for (i = 0; i < nintf; ++i) { for (j = 0; j < nintf; ++j) { if (inums[j] == i) break; } if (j >= nintf) dev_warn(ddev, "config %d has no interface number " "%d\n", cfgno, i); } /* Allocate the usb_interface_caches and altsetting arrays */ for (i = 0; i < nintf; ++i) { j = nalts[i]; if (j > USB_MAXALTSETTING) { dev_warn(ddev, "too many alternate settings for " "config %d interface %d: %d, " "using maximum allowed: %d\n", cfgno, inums[i], j, USB_MAXALTSETTING); nalts[i] = j = USB_MAXALTSETTING; } len = sizeof(*intfc) + sizeof(struct usb_host_interface) * j; config->intf_cache[i] = intfc = kzalloc(len, GFP_KERNEL); if (!intfc) return -ENOMEM; kref_init(&intfc->ref); } /* Skip over any Class Specific or Vendor Specific descriptors; * find the first interface descriptor */ config->extra = buffer; i = find_next_descriptor(buffer, size, USB_DT_INTERFACE, USB_DT_INTERFACE, &n); config->extralen = i; if (n > 0) dev_dbg(ddev, "skipped %d descriptor%s after %s\n", n, plural(n), "configuration"); buffer += i; size -= i; /* Parse all the interface/altsetting descriptors */ while (size > 0) { retval = usb_parse_interface(ddev, cfgno, config, buffer, size, inums, nalts); if (retval < 0) return retval; buffer += retval; size -= retval; } /* Check for missing altsettings */ for (i = 0; i < nintf; ++i) { intfc = config->intf_cache[i]; for (j = 0; j < intfc->num_altsetting; ++j) { for (n = 0; n < intfc->num_altsetting; ++n) { if (intfc->altsetting[n].desc. bAlternateSetting == j) break; } if (n >= intfc->num_altsetting) dev_warn(ddev, "config %d interface %d has no " "altsetting %d\n", cfgno, inums[i], j); } } return 0; } // hub-only!! ... and only exported for reset/reinit path. // otherwise used internally on disconnect/destroy path void usb_destroy_configuration(struct usb_device *dev) { int c, i; if (!dev->config) return; if (dev->rawdescriptors) { for (i = 0; i < dev->descriptor.bNumConfigurations; i++) kfree(dev->rawdescriptors[i]); kfree(dev->rawdescriptors); dev->rawdescriptors = NULL; } for (c = 0; c < dev->descriptor.bNumConfigurations; c++) { struct usb_host_config *cf = &dev->config[c]; kfree(cf->string); for (i = 0; i < cf->desc.bNumInterfaces; i++) { if (cf->intf_cache[i]) kref_put(&cf->intf_cache[i]->ref, usb_release_interface_cache); } } kfree(dev->config); dev->config = NULL; } // hub-only!! ... and only in reset path, or usb_new_device() // (used by real hubs and virtual root hubs) int usb_get_configuration(struct usb_device *dev) { struct device *ddev = &dev->dev; int ncfg = dev->descriptor.bNumConfigurations; int result = -ENOMEM; unsigned int cfgno, length; unsigned char *buffer; unsigned char *bigbuffer; struct usb_config_descriptor *desc; if (ncfg > USB_MAXCONFIG) { dev_warn(ddev, "too many configurations: %d, " "using maximum allowed: %d\n", ncfg, USB_MAXCONFIG); dev->descriptor.bNumConfigurations = ncfg = USB_MAXCONFIG; } if (ncfg < 1) { dev_err(ddev, "no configurations\n"); return -EINVAL; } length = ncfg * sizeof(struct usb_host_config); dev->config = kzalloc(length, GFP_KERNEL); if (!dev->config) goto err2; length = ncfg * sizeof(char *); dev->rawdescriptors = kzalloc(length, GFP_KERNEL); if (!dev->rawdescriptors) goto err2; buffer = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL); if (!buffer) goto err2; desc = (struct usb_config_descriptor *)buffer; for (cfgno = 0; cfgno < ncfg; cfgno++) { /* We grab just the first descriptor so we know how long * the whole configuration is */ result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, USB_DT_CONFIG_SIZE); if (result < 0) { dev_err(ddev, "unable to read config index %d " "descriptor/%s\n", cfgno, "start"); dev_err(ddev, "chopping to %d config(s)\n", cfgno); dev->descriptor.bNumConfigurations = cfgno; break; } else if (result < 4) { dev_err(ddev, "config index %d descriptor too short " "(expected %i, got %i)\n", cfgno, USB_DT_CONFIG_SIZE, result); result = -EINVAL; goto err; } length = max((int) le16_to_cpu(desc->wTotalLength), USB_DT_CONFIG_SIZE); /* Now that we know the length, get the whole thing */ bigbuffer = kmalloc(length, GFP_KERNEL); if (!bigbuffer) { result = -ENOMEM; goto err; } result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, bigbuffer, length); if (result < 0) { dev_err(ddev, "unable to read config index %d " "descriptor/%s\n", cfgno, "all"); kfree(bigbuffer); goto err; } if (result < length) { dev_warn(ddev, "config index %d descriptor too short " "(expected %i, got %i)\n", cfgno, length, result); length = result; } dev->rawdescriptors[cfgno] = bigbuffer; result = usb_parse_configuration(&dev->dev, cfgno, &dev->config[cfgno], bigbuffer, length); if (result < 0) { ++cfgno; goto err; } } result = 0; err: kfree(buffer); dev->descriptor.bNumConfigurations = cfgno; err2: if (result == -ENOMEM) dev_err(ddev, "out of memory\n"); return result; }