ncpsign_kernel.c 3.6 KB

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  1. /*
  2. * ncpsign_kernel.c
  3. *
  4. * Arne de Bruijn (arne@knoware.nl), 1997
  5. *
  6. */
  7. #ifdef CONFIG_NCPFS_PACKET_SIGNING
  8. #include <linux/string.h>
  9. #include <linux/ncp.h>
  10. #include <linux/bitops.h>
  11. #include "ncpsign_kernel.h"
  12. /* i386: 32-bit, little endian, handles mis-alignment */
  13. #ifdef __i386__
  14. #define GET_LE32(p) (*(int *)(p))
  15. #define PUT_LE32(p,v) { *(int *)(p)=v; }
  16. #else
  17. /* from include/ncplib.h */
  18. #define BVAL(buf,pos) (((__u8 *)(buf))[pos])
  19. #define PVAL(buf,pos) ((unsigned)BVAL(buf,pos))
  20. #define BSET(buf,pos,val) (BVAL(buf,pos) = (val))
  21. static inline __u16
  22. WVAL_LH(__u8 * buf, int pos)
  23. {
  24. return PVAL(buf, pos) | PVAL(buf, pos + 1) << 8;
  25. }
  26. static inline __u32
  27. DVAL_LH(__u8 * buf, int pos)
  28. {
  29. return WVAL_LH(buf, pos) | WVAL_LH(buf, pos + 2) << 16;
  30. }
  31. static inline void
  32. WSET_LH(__u8 * buf, int pos, __u16 val)
  33. {
  34. BSET(buf, pos, val & 0xff);
  35. BSET(buf, pos + 1, val >> 8);
  36. }
  37. static inline void
  38. DSET_LH(__u8 * buf, int pos, __u32 val)
  39. {
  40. WSET_LH(buf, pos, val & 0xffff);
  41. WSET_LH(buf, pos + 2, val >> 16);
  42. }
  43. #define GET_LE32(p) DVAL_LH(p,0)
  44. #define PUT_LE32(p,v) DSET_LH(p,0,v)
  45. #endif
  46. static void nwsign(char *r_data1, char *r_data2, char *outdata) {
  47. int i;
  48. unsigned int w0,w1,w2,w3;
  49. static int rbit[4]={0, 2, 1, 3};
  50. #ifdef __i386__
  51. unsigned int *data2=(int *)r_data2;
  52. #else
  53. unsigned int data2[16];
  54. for (i=0;i<16;i++)
  55. data2[i]=GET_LE32(r_data2+(i<<2));
  56. #endif
  57. w0=GET_LE32(r_data1);
  58. w1=GET_LE32(r_data1+4);
  59. w2=GET_LE32(r_data1+8);
  60. w3=GET_LE32(r_data1+12);
  61. for (i=0;i<16;i+=4) {
  62. w0=rol32(w0 + ((w1 & w2) | ((~w1) & w3)) + data2[i+0],3);
  63. w3=rol32(w3 + ((w0 & w1) | ((~w0) & w2)) + data2[i+1],7);
  64. w2=rol32(w2 + ((w3 & w0) | ((~w3) & w1)) + data2[i+2],11);
  65. w1=rol32(w1 + ((w2 & w3) | ((~w2) & w0)) + data2[i+3],19);
  66. }
  67. for (i=0;i<4;i++) {
  68. w0=rol32(w0 + (((w2 | w3) & w1) | (w2 & w3)) + 0x5a827999 + data2[i+0],3);
  69. w3=rol32(w3 + (((w1 | w2) & w0) | (w1 & w2)) + 0x5a827999 + data2[i+4],5);
  70. w2=rol32(w2 + (((w0 | w1) & w3) | (w0 & w1)) + 0x5a827999 + data2[i+8],9);
  71. w1=rol32(w1 + (((w3 | w0) & w2) | (w3 & w0)) + 0x5a827999 + data2[i+12],13);
  72. }
  73. for (i=0;i<4;i++) {
  74. w0=rol32(w0 + ((w1 ^ w2) ^ w3) + 0x6ed9eba1 + data2[rbit[i]+0],3);
  75. w3=rol32(w3 + ((w0 ^ w1) ^ w2) + 0x6ed9eba1 + data2[rbit[i]+8],9);
  76. w2=rol32(w2 + ((w3 ^ w0) ^ w1) + 0x6ed9eba1 + data2[rbit[i]+4],11);
  77. w1=rol32(w1 + ((w2 ^ w3) ^ w0) + 0x6ed9eba1 + data2[rbit[i]+12],15);
  78. }
  79. PUT_LE32(outdata,(w0+GET_LE32(r_data1)) & 0xffffffff);
  80. PUT_LE32(outdata+4,(w1+GET_LE32(r_data1+4)) & 0xffffffff);
  81. PUT_LE32(outdata+8,(w2+GET_LE32(r_data1+8)) & 0xffffffff);
  82. PUT_LE32(outdata+12,(w3+GET_LE32(r_data1+12)) & 0xffffffff);
  83. }
  84. /* Make a signature for the current packet and add it at the end of the */
  85. /* packet. */
  86. void __sign_packet(struct ncp_server *server, const char *packet, size_t size, __u32 totalsize, void *sign_buff) {
  87. unsigned char data[64];
  88. memcpy(data, server->sign_root, 8);
  89. *(__u32*)(data + 8) = totalsize;
  90. if (size < 52) {
  91. memcpy(data + 12, packet, size);
  92. memset(data + 12 + size, 0, 52 - size);
  93. } else {
  94. memcpy(data + 12, packet, 52);
  95. }
  96. nwsign(server->sign_last, data, server->sign_last);
  97. memcpy(sign_buff, server->sign_last, 8);
  98. }
  99. int sign_verify_reply(struct ncp_server *server, const char *packet, size_t size, __u32 totalsize, const void *sign_buff) {
  100. unsigned char data[64];
  101. unsigned char hash[16];
  102. memcpy(data, server->sign_root, 8);
  103. *(__u32*)(data + 8) = totalsize;
  104. if (size < 52) {
  105. memcpy(data + 12, packet, size);
  106. memset(data + 12 + size, 0, 52 - size);
  107. } else {
  108. memcpy(data + 12, packet, 52);
  109. }
  110. nwsign(server->sign_last, data, hash);
  111. return memcmp(sign_buff, hash, 8);
  112. }
  113. #endif /* CONFIG_NCPFS_PACKET_SIGNING */