Line data    Source code

       1             : #ifndef HEADER_fd_src_ballet_sbpf_fd_sbpf_loader_h
       2             : #define HEADER_fd_src_ballet_sbpf_fd_sbpf_loader_h
       3             : 
       4             : /* fd_sbpf_loader prepares an sBPF program for execution.  This involves
       5             :    parsing and dynamic relocation.
       6             : 
       7             :    Due to historical reasons, this loader is neither a pure static
       8             :    linker nor a real dynamic loader.  For instance, it will ignore the
       9             :    program header table and instead load specific sections at predefined
      10             :    addresses.  However, it will perform dynamic relocation. */
      11             : 
      12             : #include "../../util/fd_util_base.h"
      13             : #include "../elf/fd_elf64.h"
      14             : 
      15             : /* Error types ********************************************************/
      16             : 
      17             : /* FIXME make error types more specific */
      18             : #define FD_SBPF_ERR_INVALID_ELF (1)
      19           3 : #define FD_SBPF_PROG_RODATA_ALIGN 8UL
      20             : 
      21       38895 : #define FD_SBPF_VERSION_COUNT (4UL)
      22         216 : #define FD_SBPF_V0            (0UL)
      23       10806 : #define FD_SBPF_V1            (1UL)
      24     2337615 : #define FD_SBPF_V2            (2UL)
      25      163731 : #define FD_SBPF_V3            (3UL)
      26             : 
      27             : /* Program struct *****************************************************/
      28             : 
      29             : /* fd_sbpf_calldests is a bit vector of valid call destinations.
      30             :    Should be configured to fit any possible program counter.  The max
      31             :    program counter is <size of ELF binary> divided by 8. */
      32             : 
      33             : #define SET_NAME fd_sbpf_calldests
      34             : #include "../../util/tmpl/fd_set_dynamic.c"
      35             : 
      36             : /* fd_sbpf_syscall_func_t is a callback implementing an sBPF syscall.
      37             :    vm is a handle to the running VM.  Returns 0 on suceess or an integer
      38             :    error code on failure.
      39             : 
      40             :    IMPORTANT SAFETY TIP!  See notes in
      41             :    flamenco/vm/syscall/fd_vm_syscall.h on what a syscall should expect
      42             :    to see and expect to return. */
      43             : 
      44             : /* FIXME: THIS BELONGS IN FLAMENCO/VM */
      45             : 
      46             : typedef int
      47             : (*fd_sbpf_syscall_func_t)( void *  vm,
      48             :                            ulong   arg0,
      49             :                            ulong   arg1,
      50             :                            ulong   arg2,
      51             :                            ulong   arg3,
      52             :                            ulong   arg4,
      53             :                            ulong * _ret );
      54             : 
      55             : /* fd_sbpf_syscalls_t maps syscall IDs => a name and a VM specific
      56             :    context.  FIXME: THIS ALSO PROBABLY BELONGS IN FLAMENCO/VM */
      57             : 
      58     1006989 : #define FD_SBPF_SYSCALLS_LG_SLOT_CNT (7)
      59             : #define FD_SBPF_SYSCALLS_SLOT_CNT    (1UL<<FD_SBPF_SYSCALLS_LG_SLOT_CNT)
      60             : 
      61             : /* The syscalls map keys should technically be of type uint since they are
      62             :    just murmur32 hashes. However, Agave's BTree allows the full range to be
      63             :    used as a key [0, UINT_MAX]. So we need to define a wider key type to
      64             :    allow for a NULL value that is outside this range. We use ulong here. */
      65             : 
      66             : struct fd_sbpf_syscalls {
      67             :   ulong                  key;  /* Murmur3-32 hash of function name */
      68             :   fd_sbpf_syscall_func_t func; /* Function pointer */
      69             :   char const *           name; /* Infinite lifetime pointer to function name */
      70             : };
      71             : 
      72             : typedef struct fd_sbpf_syscalls fd_sbpf_syscalls_t;
      73             : 
      74             : #define MAP_NAME              fd_sbpf_syscalls
      75       10701 : #define MAP_T                 fd_sbpf_syscalls_t
      76        3003 : #define MAP_HASH_T            ulong
      77      986505 : #define MAP_KEY_NULL          ULONG_MAX         /* Any number greater than UINT_MAX works */
      78        4758 : #define MAP_KEY_INVAL(k)      ( k > UINT_MAX )  /* Force keys to uint size */
      79        3432 : #define MAP_KEY_EQUAL(k0,k1)  (k0)==(k1)
      80             : #define MAP_KEY_EQUAL_IS_SLOW 0
      81        3003 : #define MAP_KEY_HASH(k)       (k)
      82             : #define MAP_MEMOIZE           0
      83     1006989 : #define MAP_LG_SLOT_CNT       FD_SBPF_SYSCALLS_LG_SLOT_CNT
      84             : #include "../../util/tmpl/fd_map.c"
      85             : 
      86             : #define FD_SBPF_SYSCALLS_FOOTPRINT (sizeof(fd_sbpf_syscalls_t) * (1UL<<FD_SBPF_SYSCALLS_LG_SLOT_CNT))
      87             : #define FD_SBPF_SYSCALLS_ALIGN     alignof(fd_sbpf_syscalls_t)
      88             : 
      89             : /* fd_sbpf_elf_info_t contains basic information extracted from an ELF
      90             :    binary. Indicates how much scratch memory and buffer size is required
      91             :    to fully load the program. */
      92             : 
      93             : struct fd_sbpf_elf_info {
      94             :   uint text_off;    /* File offset of .text section (overlaps rodata segment) */
      95             :   uint text_cnt;    /* Instruction count */
      96             :   ulong text_sz;    /* Length of text segment */
      97             : 
      98             :   uint dynstr_off;  /* File offset of .dynstr section (0=missing) */
      99             :   uint dynstr_sz;   /* Dynstr char count */
     100             : 
     101             :   uint rodata_sz;         /* size of rodata segment */
     102             :   uint rodata_footprint;  /* size of ELF binary */
     103             : 
     104             :   /* Known section indices
     105             :      In [-1,USHORT_MAX) where -1 means "not found" */
     106             :   int shndx_text;
     107             :   int shndx_symtab;
     108             :   int shndx_strtab;
     109             :   int shndx_dyn;
     110             :   int shndx_dynstr;
     111             : 
     112             :   /* Known program header indices (like shndx_*) */
     113             :   int phndx_dyn;
     114             : 
     115             :   uint entry_pc;  /* Program counter of entry point
     116             :                      NOTE: MIGHT BE OUT OF BOUNDS! */
     117             : 
     118             :   /* Bitmap of sections to be loaded (LSB => MSB) */
     119             :   ulong loaded_sections[ 1024UL ];
     120             : 
     121             :   /* SBPF version, SIMD-0161 */
     122             :   uint sbpf_version;
     123             : };
     124             : typedef struct fd_sbpf_elf_info fd_sbpf_elf_info_t;
     125             : 
     126             : /* fd_sbpf_program_t describes a loaded program in memory.
     127             : 
     128             :    [rodata,rodata+rodata_sz) is an externally allocated buffer holding
     129             :    the read-only segment to be loaded into the VM.  WARNING: The rodata
     130             :    area required doing load (rodata_footprint) is larger than the area
     131             :    mapped into the VM (rodata_sz).
     132             : 
     133             :    [text,text+8*text_cnt) is a sub-region of the read-only segment
     134             :    containing executable code. */
     135             : 
     136             : struct __attribute__((aligned(32UL))) fd_sbpf_program {
     137             :   fd_sbpf_elf_info_t info;
     138             : 
     139             :   /* rodata segment to be mapped into VM memory */
     140             :   void * rodata;     /* rodata segment data */
     141             :   ulong  rodata_sz;  /* size of data */
     142             : 
     143             :   /* text section within rodata segment */
     144             :   ulong * text;
     145             :   ulong   text_cnt;  /* instruction count */
     146             :   ulong   text_off;  /* instruction offset for use in CALL_REG instructions */
     147             :   ulong   text_sz;   /* size of text segment */
     148             :   ulong   entry_pc;  /* entrypoint PC (at text[ entry_pc - start_pc ]) ... FIXME: HMMMM ... CODE SEEMS TO USE TEXT[ ENTRY_PC ] */
     149             : 
     150             :   /* Bit vector of valid call destinations (bit count is rodata_sz) */
     151             :   void * calldests_shmem;
     152             :   /* Local join to bit vector of valid call destinations */
     153             :   fd_sbpf_calldests_t * calldests;
     154             : };
     155             : typedef struct fd_sbpf_program fd_sbpf_program_t;
     156             : 
     157             : /* Prototypes *********************************************************/
     158             : 
     159             : FD_PROTOTYPES_BEGIN
     160             : 
     161             : /* fd_sbpf_elf_peek partially parses the given ELF file in memory region
     162             :    [bin,bin+bin_sz)  Populates `info`.  Returns `info` on success.  On
     163             :    failure, returns NULL.
     164             : 
     165             :    elf_deploy_checks: The Agave ELF loader introduced additional checks
     166             :    that would fail on (certain) existing mainnet programs. Since it is
     167             :    impossible to retroactively enforce these checks on already deployed programs,
     168             :    a guard flag is used to enable these checks only when deploying programs.
     169             : 
     170             :    sbpf_min_version, sbpf_max_version: determine the min, max SBPF version
     171             :    allowed, version is retrieved from the ELF header. See SIMD-0161. */
     172             : 
     173             : fd_sbpf_elf_info_t *
     174             : fd_sbpf_elf_peek( fd_sbpf_elf_info_t * info,
     175             :                   void const *         bin,
     176             :                   ulong                bin_sz,
     177             :                   int                  elf_deploy_checks,
     178             :                   uint                 sbpf_min_version,
     179             :                   uint                 sbpf_max_version );
     180             : 
     181             : /* fd_sbpf_program_{align,footprint} return the alignment and size
     182             :    requirements of the memory region backing the fd_sbpf_program_t
     183             :    object. */
     184             : 
     185             : FD_FN_CONST ulong
     186             : fd_sbpf_program_align( void );
     187             : 
     188             : FD_FN_PURE ulong
     189             : fd_sbpf_program_footprint( fd_sbpf_elf_info_t const * info );
     190             : 
     191             : /* fd_sbpf_program_new formats prog_mem to hold an fd_sbpf_program_t.
     192             :    prog_mem must match footprint requirements of the given elf_info.
     193             :    elf_info may be deallocated on return.
     194             : 
     195             :    rodata is the read-only segment buffer that the program is configured
     196             :    against and must be valid for the lifetime of the program object. It
     197             :    should also meet the alignment requirements of the program object.
     198             :    */
     199             : 
     200             : fd_sbpf_program_t *
     201             : fd_sbpf_program_new( void *                     prog_mem,
     202             :                      fd_sbpf_elf_info_t const * elf_info,
     203             :                      void *                     rodata );
     204             : 
     205             : /* fd_sbpf_program_load loads an eBPF program for execution.
     206             : 
     207             :    prog is a program object allocated with fd_sbpf_program_new and must
     208             :    match the footprint requirements of this ELF file.
     209             : 
     210             :    Initializes and populates the program struct with information about
     211             :    the program and prepares the read-only segment provided in
     212             :    fd_sbpf_program_new.
     213             : 
     214             :    Memory region [bin,bin+bin_sz) contains the ELF file to be loaded.
     215             : 
     216             :    On success, returns 0.
     217             :    On error, returns FD_SBPF_ERR_* and leaves prog in an undefined
     218             :    state.
     219             : 
     220             :    ### Compliance
     221             : 
     222             :    This loader does not yet adhere to Solana protocol specs.
     223             :    It is mostly compatible with solana-labs/rbpf v0.3.0 with the
     224             :    following config:
     225             : 
     226             :      new_elf_parser:     true
     227             :      enable_elf_vaddr:   false
     228             :      reject_broken_elfs: elf_deploy_checks
     229             : 
     230             :    For documentation on these config params, see:
     231             :    https://github.com/solana-labs/rbpf/blob/v0.3.0/src/vm.rs#L198
     232             : 
     233             :    Solana/Agave equivalent:
     234             :    https://github.com/solana-labs/rbpf/blob/v0.8.0/src/elf.rs#L361
     235             :    */
     236             : 
     237             : int
     238             : fd_sbpf_program_load( fd_sbpf_program_t *  prog,
     239             :                       void const *         bin,
     240             :                       ulong                bin_sz,
     241             :                       fd_sbpf_syscalls_t * syscalls,
     242             :                       int                  elf_deploy_checks );
     243             : 
     244             : /* fd_sbpf_program_delete destroys the program object and unformats the
     245             :    memory regions holding it. */
     246             : 
     247             : void *
     248             : fd_sbpf_program_delete( fd_sbpf_program_t * program );
     249             : 
     250             : /* fd_csv_strerror: Returns a cstr describing the source line and error
     251             :    kind after the last call to `fd_sbpf_program_load` from the same
     252             :    thread returned non-zero.
     253             :    Always returns a valid cstr, though the content is undefined in case
     254             :    the last call to `fd_sbpf_program_load` returned zero (success). */
     255             : 
     256             : char const *
     257             : fd_sbpf_strerror( void );
     258             : 
     259             : FD_PROTOTYPES_END
     260             : 
     261             : #endif /* HEADER_fd_src_ballet_sbpf_fd_sbpf_loader_h */