libkern/crypto/corecrypto_sha1.c

   1
   2 #include <libkern/crypto/crypto_internal.h>
   3 #include <libkern/crypto/sha1.h>
   4 #include <kern/debug.h>
   5 #include <corecrypto/ccdigest.h>
   6
   7
   8 static uint64_t getCount(SHA1_CTX *ctx)
   9 {
  10         return ctx->c.b64[0];
  11 }
  12
  13 static void setCount(SHA1_CTX *ctx, uint64_t count)
  14 {
  15         ctx->c.b64[0]=count;
  16 }
  17
  18 /* Copy a ccdigest ctx into a legacy SHA1 context */
  19 static void DiToSHA1(const struct ccdigest_info *di, struct ccdigest_ctx *di_ctx, SHA1_CTX *sha1_ctx)
  20 {
  21         setCount(sha1_ctx, ccdigest_nbits(di, di_ctx)/8+ccdigest_num(di, di_ctx));
  22         memcpy(sha1_ctx->m.b8, ccdigest_data(di, di_ctx), di->block_size);
  23         memcpy(sha1_ctx->h.b8, ccdigest_state_ccn(di, di_ctx), di->state_size);
  24 }
  25
  26 /* Copy a legacy SHA1 context into a ccdigest ctx  */
  27 static void SHA1ToDi(const struct ccdigest_info *di, SHA1_CTX *sha1_ctx, struct ccdigest_ctx *di_ctx)
  28 {
  29         uint64_t count = getCount(sha1_ctx);
  30
  31         ccdigest_num(di, di_ctx)=count%di->block_size;
  32         ccdigest_nbits(di, di_ctx)=(count-ccdigest_num(di, di_ctx))*8;
  33         memcpy(ccdigest_data(di, di_ctx), sha1_ctx->m.b8, di->block_size);
  34         memcpy(ccdigest_state_ccn(di, di_ctx), sha1_ctx->h.b8, di->state_size);
  35 }
  36
  37 void SHA1Init(SHA1_CTX *ctx)
  38 {
  39         const struct ccdigest_info *di=g_crypto_funcs->ccsha1_di;
  40         ccdigest_di_decl(di, di_ctx);
  41
  42         g_crypto_funcs->ccdigest_init_fn(di, di_ctx);
  43
  44         DiToSHA1(di, di_ctx, ctx);
  45 }
  46
  47 void SHA1Update(SHA1_CTX *ctx, const void *data, size_t len)
  48 {
  49         const struct ccdigest_info *di=g_crypto_funcs->ccsha1_di;
  50         ccdigest_di_decl(di, di_ctx);
  51
  52         SHA1ToDi(di, ctx, di_ctx);
  53         g_crypto_funcs->ccdigest_update_fn(di, di_ctx, len, data);
  54         DiToSHA1(di, di_ctx, ctx);
  55 }
  56
  57 void SHA1Final(void *digest, SHA1_CTX *ctx)
  58 {
  59         const struct ccdigest_info *di=g_crypto_funcs->ccsha1_di;
  60         ccdigest_di_decl(di, di_ctx);
  61
  62         SHA1ToDi(di, ctx, di_ctx);
  63         ccdigest_final(di, di_ctx, digest);
  64 }
  65
  66 #ifdef XNU_KERNEL_PRIVATE
  67 void SHA1UpdateUsePhysicalAddress(SHA1_CTX *ctx, const void *data, size_t len)
  68 {
  69         //TODO: What the hell ?
  70         SHA1Update(ctx, data, len);
  71 }
  72 #endif
  73
  74 /* This is not publicised in header, but exported in libkern.exports */
  75 void SHA1Final_r(SHA1_CTX *context, void *digest);
  76 void SHA1Final_r(SHA1_CTX *context, void *digest)
  77 {
  78         SHA1Final(digest, context);
  79 }
  80
  81
  82 /*
  83  * This function is called by the SHA1 hardware kext during its init.
  84  * This will register the function to call to perform SHA1 using hardware.
  85  */
  86 #include <sys/types.h>
  87 #include <libkern/OSAtomic.h>
  88 #include <sys/systm.h>
  89
  90 typedef kern_return_t (*InKernelPerformSHA1Func)(void *ref, const void *data, size_t dataLen, u_int32_t *inHash, u_int32_t options, u_int32_t *outHash, Boolean usePhysicalAddress);
  91 void sha1_hardware_hook(Boolean option, InKernelPerformSHA1Func func, void *ref);
  92 static void *SHA1Ref;
  93 static InKernelPerformSHA1Func performSHA1WithinKernelOnly;
  94
  95 void sha1_hardware_hook(Boolean option, InKernelPerformSHA1Func func, void *ref)
  96 {
  97         if(option) {
  98                 // Establish the hook. The hardware is ready.
  99                 OSCompareAndSwapPtr((void*)NULL, (void*)ref, (void * volatile*)&SHA1Ref);
 100
 101                 if(!OSCompareAndSwapPtr((void *)NULL, (void *)func, (void * volatile *)&performSHA1WithinKernelOnly)) {
 102                         panic("sha1_hardware_hook: Called twice.. Should never happen\n");
 103                 }
 104         }
 105         else {
 106                 // The hardware is going away. Tear down the hook.
 107                 performSHA1WithinKernelOnly = NULL;
 108                 SHA1Ref = NULL;
 109         }
 110 }