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make rfb use copy_pixels
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1#include <stdint.h>
2#include "packet.h"
3
4#define PTE_FOR(x) (((unsigned int)(x) >> 12) & 0x3FF)
5#define PDE_FOR(x) ((unsigned int)(x) >> 22)
6#define ADDR_12_MASK(x) ((unsigned int)(x) & ~((1 << 12) - 1))
7#define ADDR_22_MASK(x) ((unsigned int)(x) & ~((1 << 22) - 1))
8#define LOWER_12(x) ((unsigned int)(x) & ((1 << 12) - 1))
9#define LOWER_22(x) ((unsigned int)(x) & ((1 << 22) - 1))
10
11#define PDE_4M_ADDR_SHIFT 22
12#define PTE_4K_ADDR_SHIFT 12
13#define PDE_TABLE_ADDR_SHIFT 12
14#define PTE_FRAME_ADDR_MASK (~((1 << PTE_4K_ADDR_SHIFT) - 1))
15#define PDE_TABLE_ADDR_MASK (~((1 << PDE_TABLE_ADDR_SHIFT) - 1))
16
17#define PDE_ATTRIB_INDEX (1 << 12)
18#define PDE_GLOBAL (1 << 8)
19#define PDE_PAGE_SIZE (1 << 7)
20#define PDE_DIRTY (1 << 6)
21#define PDE_ACCESSED (1 << 5)
22#define PDE_NO_CACHE (1 << 4)
23#define PDE_WRITE_THROUGH (1 << 3)
24#define PDE_USER (1 << 2)
25#define PDE_READ_WRITE (1 << 1)
26#define PDE_PRESENT (1 << 0)
27
28#define PTE_GLOBAL (1 << 8)
29#define PTE_ATTRIB_INDEX (1 << 7)
30#define PTE_DIRTY (1 << 6)
31#define PTE_ACCESSED (1 << 5)
32#define PTE_NO_CACHE (1 << 4)
33#define PTE_WRITE_THROUGH (1 << 3)
34#define PTE_USER (1 << 2)
35#define PTE_READ_WRITE (1 << 1)
36#define PTE_PRESENT (1 << 0)
37
38asm ("get_cr3: mov %cr3, %eax \n ret");
39uint32_t * get_cr3();
40
41void * l2p (void * addr) {
42
43 uint32_t * cr3 = get_cr3();
44 uint32_t * page_table;
45 uint32_t pde, pte;
46
47 pde = cr3[PDE_FOR(addr)];
48
49 if (!(pde & PDE_PRESENT)) {
50 return 0;
51 }
52
53 if (pde & PDE_PAGE_SIZE) {
54 return (void *)(ADDR_22_MASK(pde) | LOWER_22(addr));
55 } else {
56 page_table = (uint32_t *)(ADDR_12_MASK(pde));
57 pte = page_table[PTE_FOR(addr)];
58
59 if (!pte & PTE_PRESENT) {
60 return 0;
61 }
62 return (void *)(ADDR_12_MASK(pte) | LOWER_12(addr));
63 }
64}
65
66packet_t * check_packet (uint32_t logical_base) {
67 packet_t * physical_base;
68
69 if (LOWER_12(logical_base) != 0) return 0;
70
71 physical_base = l2p((void *)logical_base);
72
73 if (!physical_base) return 0;
74 if (physical_base->signature != 0x1BADD00D) return 0;
75
76 return physical_base;
77}
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