diff options
Diffstat (limited to 'core/pxe.c')
| -rw-r--r-- | core/pxe.c | 159 |
1 files changed, 76 insertions, 83 deletions
@@ -336,7 +336,6 @@ static int pxe_get_cached_info(int type) */ static int is_url(char *url) { - while (*url) { if(! strncmp(url, "://", 3)) return 1; @@ -1251,42 +1250,43 @@ static void ip_init(void) * return 1 for success, 0 for failure. * */ -static int is_pxe(char *buf) +static int is_pxe(const void *buf) { - int i = buf[4]; + const struct pxe_t *pxe = buf; + const uint8_t *p = buf; + int i = pxe->structlength; uint8_t sum = 0; - if (memcmp(buf, "!PXE", 4) || i < 0x58) + if (i < sizeof(struct pxe_t) || + memcmp(pxe->signature, "!PXE", 4)) return 0; while (i--) - sum += *buf++; + sum += *p++; - if (sum == 0) - return 1; - else - return 0; + return sum == 0; } /** * Just like is_pxe, it checks PXENV+ structure * */ -static int is_pxenv(char *buf) +static int is_pxenv(const void *buf) { - int i = buf[8]; + const struct pxenv_t *pxenv = buf; + const uint8_t *p = buf; + int i = pxenv->length; uint8_t sum = 0; - if (memcmp(buf, "PXENV+", 6) || i < 0x28) + /* The pxeptr field isn't present in old versions */ + if (i < offsetof(struct pxenv_t, pxeptr) || + memcmp(pxenv->signature, "PXENV+", 6)) return 0; while (i--) - sum += *buf++; + sum += *p++; - if (sum == 0) - return 1; - else - return 0; + return sum == 0; } @@ -1309,29 +1309,29 @@ static int is_pxenv(char *buf) ; ********************************************************************/ -static inline int memory_scan(uint16_t seg, int (*func)(char *)) +static const void *memory_scan(uintptr_t start, int (*func)(const void *)) { - while (seg < 0xA000) { - if (func(MK_PTR(seg, 0))) - return 1; /* found it */ - seg++; + const char *ptr; + + /* Scan each 16 bytes of conventional memory before the VGA region */ + for (ptr = (const char *)start; ptr < (const char *)0xA0000; ptr += 16) { + if (func(ptr)) + return ptr; /* found it! */ + ptr += 16; } - return 0; + return NULL; } -static int memory_scan_for_pxe_struct(void) +static const struct pxe_t *memory_scan_for_pxe_struct(void) { extern uint16_t BIOS_fbm; /* Starting segment */ - uint16_t seg = BIOS_fbm << (10 - 4); - return memory_scan(seg, is_pxe); + return memory_scan(BIOS_fbm << 10, is_pxe); } -static int memory_scan_for_pxenv_struct(void) +static const struct pxenv_t *memory_scan_for_pxenv_struct(void) { - uint16_t seg = 0x1000; - - return memory_scan(seg, is_pxenv); + return memory_scan(0x10000, is_pxenv); } /* @@ -1349,11 +1349,16 @@ static int memory_scan_for_pxenv_struct(void) */ static void pxe_init(void) { + extern void pxe_int1a(void); char plan = 'A'; uint16_t seg, off; uint16_t code_seg, code_len; uint16_t data_seg, data_len; char *base = GET_PTR(InitStack); + com32sys_t regs; + const char *type; + const struct pxenv_t *pxenv; + const struct pxe_t *pxe; /* Assume API version 2.1 */ APIVer = 0x201; @@ -1361,43 +1366,39 @@ static void pxe_init(void) /* Plan A: !PXE structure as SS:[SP + 4] */ off = *(uint16_t *)(base + 48); seg = *(uint16_t *)(base + 50); - if (is_pxe(MK_PTR(seg, off))) + pxe = MK_PTR(seg, off); + if (is_pxe(pxe)) goto have_pxe; /* Plan B: PXENV+ structure at [ES:BX] */ plan++; off = *(uint16_t *)(base + 24); /* Original BX */ seg = *(uint16_t *)(base + 4); /* Original ES */ - if (is_pxenv(MK_PTR(seg, off))) + pxenv = MK_PTR(seg, off); + if (is_pxenv(pxenv)) goto have_pxenv; /* * Plan C: PXENV+ structure via INT 1Ah AX=5650h - * - * for now, we just skip it since it must be run in Real mode */ - extern void plan_c(void); plan++; -#if 0 - goto plan_D; - call16(plan_c, regs, regs); - if (((regs->eflags.l & EFLAGS_CF) == 0) && (regs->eax.w[0] == 0x564e)) { - seg = regs->es; - off = regs->ebx.w[0]; - if (is_pxenv(MK_PTR(seg, off))) + memset(®s, 0, sizeof regs); + regs.eax.w[0] = 0x5650; + call16(pxe_int1a, ®s, ®s); + if (!(regs.eflags.l & EFLAGS_CF) && (regs.eax.w[0] == 0x564e)) { + pxenv = MK_PTR(regs.es, regs.ebx.w[0]); + if (is_pxenv(pxenv)) goto have_pxenv; } - plan_D: -#endif /* Plan D: !PXE memory scan */ plan++; - if (memory_scan_for_pxe_struct()) + if ((pxe = memory_scan_for_pxe_struct())) goto have_pxe; /* Plan E: PXENV+ memory scan */ plan++; - if (memory_scan_for_pxenv_struct()) + if ((pxenv = memory_scan_for_pxenv_struct())) goto have_pxenv; /* Found nothing at all !! */ @@ -1405,59 +1406,51 @@ static void pxe_init(void) call16(kaboom, NULL, NULL); have_pxenv: - base = MK_PTR(seg, off); - APIVer = *(uint16_t *)(base + 6); + APIVer = pxenv->version; printf("Found PXENV+ structure\nPXE API version is %04x\n", APIVer); /* if the API version number is 0x0201 or higher, use the !PXE structure */ if (APIVer >= 0x201) { - if (*(char *)(base + 8) < 0x2c) { /* Length of PXENV+ structure in bytes */ - if (memory_scan_for_pxe_struct()) - goto have_pxe; - } - - off = *(uint16_t *)(base + 0x28); - seg = *(uint16_t *)(base + 0x2a); - if (is_pxe(MK_PTR(seg, off))) - goto have_pxe; - /* - * Nope, !PXE structuremissing despite API 2.1+, or at least - * the pointer is missing. Do a last-ditch attempt to find it - */ - if (memory_scan_for_pxe_struct()) - goto have_pxe; + if (pxenv->length >= sizeof(struct pxenv_t)) { + pxe = GET_PTR(pxenv->pxeptr); + if (is_pxe(pxe)) + goto have_pxe; + /* + * Nope, !PXE structure missing despite API 2.1+, or at least + * the pointer is missing. Do a last-ditch attempt to find it + */ + if ((pxe = memory_scan_for_pxe_struct())) + goto have_pxe; + } } /* Otherwise, no dice, use PXENV+ structure */ - data_len = *(uint16_t *)(base + 0x22); /* UNDI data len */ - data_seg = *(uint16_t *)(base + 0x20); /* UNDI data seg */ - code_len = *(uint16_t *)(base + 0x26); /* UNDI code len */ - code_seg = *(uint16_t *)(base + 0x24); /* UNDI code seg */ - PXEEntry = *(far_ptr_t *)(base + 0x0a); /* PXENV+ entry point */ - printf("PXENV+ entry point found (we hope) at "); + data_len = pxenv->undidatasize; + data_seg = pxenv->undidataseg; + code_len = pxenv->undicodesize; + code_seg = pxenv->undicodeseg; + PXEEntry = pxenv->rmentry; + type = "PXENV+"; goto have_entrypoint; have_pxe: - base = MK_PTR(seg, off); - - data_len = *(uint16_t *)(base + 0x2e); /* UNDI data len */ - data_seg = *(uint16_t *)(base + 0x28); /* UNDI data seg */ - code_len = *(uint16_t *)(base + 0x36); /* UNDI code len */ - code_seg = *(uint16_t *)(base + 0x30); /* UNDI code seg */ - PXEEntry = *(far_ptr_t *)(base + 0x10); /* !PXE entry point */ - printf("!PXE entry point found (we hope) at "); + data_len = pxe->seg[PXE_Seg_UNDIData].size; + data_seg = pxe->seg[PXE_Seg_UNDIData].sel; + code_len = pxe->seg[PXE_Seg_UNDICode].size; + code_seg = pxe->seg[PXE_Seg_UNDICode].sel; + PXEEntry = pxe->entrypointsp; + type = "!PXE"; have_entrypoint: - printf("%04X:%04X via plan %c\n", PXEEntry.seg, PXEEntry.offs, plan); + printf("%s entry point found (we hope) at %04X:%04X via plan %c\n", + type, PXEEntry.seg, PXEEntry.offs, plan); printf("UNDI code segment at %04X len %04X\n", code_seg, code_len); - code_seg = code_seg + ((code_len + 15) >> 4); - printf("UNDI data segment at %04X len %04X\n", data_seg, data_len); + + code_seg = code_seg + ((code_len + 15) >> 4); data_seg = data_seg + ((data_len + 15) >> 4); - - + RealBaseMem = MAX(code_seg,data_seg) >> 6; /* Convert to kilobytes */ - //regs->es = regs->ds; /* Restore the es segment */ } /* |