diff options
Diffstat (limited to 'pdf/pdf_crypt.c')
| -rw-r--r-- | pdf/pdf_crypt.c | 212 |
1 files changed, 111 insertions, 101 deletions
diff --git a/pdf/pdf_crypt.c b/pdf/pdf_crypt.c index 59423a38..b65786d9 100644 --- a/pdf/pdf_crypt.c +++ b/pdf/pdf_crypt.c @@ -1,5 +1,5 @@ -#include "fitz.h" -#include "mupdf.h" +#include "fitz-internal.h" +#include "mupdf-internal.h" enum { @@ -20,11 +20,11 @@ struct pdf_crypt_filter_s struct pdf_crypt_s { - fz_obj *id; + pdf_obj *id; int v; int length; - fz_obj *cf; + pdf_obj *cf; pdf_crypt_filter stmf; pdf_crypt_filter strf; @@ -40,7 +40,7 @@ struct pdf_crypt_s fz_context *ctx; }; -static void pdf_parse_crypt_filter(fz_context *ctx, pdf_crypt_filter *cf, fz_obj *dict, char *name, int defaultlength); +static void pdf_parse_crypt_filter(fz_context *ctx, pdf_crypt_filter *cf, pdf_obj *dict, char *name, int defaultlength); /* * Create crypt object for decrypting strings and streams @@ -48,31 +48,31 @@ static void pdf_parse_crypt_filter(fz_context *ctx, pdf_crypt_filter *cf, fz_obj */ pdf_crypt * -pdf_new_crypt(fz_context *ctx, fz_obj *dict, fz_obj *id) +pdf_new_crypt(fz_context *ctx, pdf_obj *dict, pdf_obj *id) { pdf_crypt *crypt; - fz_obj *obj; + pdf_obj *obj; crypt = fz_malloc_struct(ctx, pdf_crypt); /* Common to all security handlers (PDF 1.7 table 3.18) */ - obj = fz_dict_gets(dict, "Filter"); - if (!fz_is_name(obj)) + obj = pdf_dict_gets(dict, "Filter"); + if (!pdf_is_name(obj)) { pdf_free_crypt(ctx, crypt); fz_throw(ctx, "unspecified encryption handler"); } - if (strcmp(fz_to_name(obj), "Standard") != 0) + if (strcmp(pdf_to_name(obj), "Standard") != 0) { pdf_free_crypt(ctx, crypt); - fz_throw(ctx, "unknown encryption handler: '%s'", fz_to_name(obj)); + fz_throw(ctx, "unknown encryption handler: '%s'", pdf_to_name(obj)); } crypt->v = 0; - obj = fz_dict_gets(dict, "V"); - if (fz_is_int(obj)) - crypt->v = fz_to_int(obj); + obj = pdf_dict_gets(dict, "V"); + if (pdf_is_int(obj)) + crypt->v = pdf_to_int(obj); if (crypt->v != 1 && crypt->v != 2 && crypt->v != 4 && crypt->v != 5) { pdf_free_crypt(ctx, crypt); @@ -82,9 +82,9 @@ pdf_new_crypt(fz_context *ctx, fz_obj *dict, fz_obj *id) crypt->length = 40; if (crypt->v == 2 || crypt->v == 4) { - obj = fz_dict_gets(dict, "Length"); - if (fz_is_int(obj)) - crypt->length = fz_to_int(obj); + obj = pdf_dict_gets(dict, "Length"); + if (pdf_is_int(obj)) + crypt->length = pdf_to_int(obj); /* work-around for pdf generators that assume length is in bytes */ if (crypt->length < 40) @@ -122,10 +122,10 @@ pdf_new_crypt(fz_context *ctx, fz_obj *dict, fz_obj *id) crypt->strf.method = PDF_CRYPT_NONE; crypt->strf.length = crypt->length; - obj = fz_dict_gets(dict, "CF"); - if (fz_is_dict(obj)) + obj = pdf_dict_gets(dict, "CF"); + if (pdf_is_dict(obj)) { - crypt->cf = fz_keep_obj(obj); + crypt->cf = pdf_keep_obj(obj); } else { @@ -134,18 +134,18 @@ pdf_new_crypt(fz_context *ctx, fz_obj *dict, fz_obj *id) fz_try(ctx) { - obj = fz_dict_gets(dict, "StmF"); - if (fz_is_name(obj)) - pdf_parse_crypt_filter(ctx, &crypt->stmf, crypt->cf, fz_to_name(obj), crypt->length); + obj = pdf_dict_gets(dict, "StmF"); + if (pdf_is_name(obj)) + pdf_parse_crypt_filter(ctx, &crypt->stmf, crypt->cf, pdf_to_name(obj), crypt->length); - obj = fz_dict_gets(dict, "StrF"); - if (fz_is_name(obj)) - pdf_parse_crypt_filter(ctx, &crypt->strf, crypt->cf, fz_to_name(obj), crypt->length); + obj = pdf_dict_gets(dict, "StrF"); + if (pdf_is_name(obj)) + pdf_parse_crypt_filter(ctx, &crypt->strf, crypt->cf, pdf_to_name(obj), crypt->length); } fz_catch(ctx) { pdf_free_crypt(ctx, crypt); - fz_throw(ctx, "cannot parse string crypt filter (%d %d R)", fz_to_num(obj), fz_to_gen(obj)); + fz_throw(ctx, "cannot parse string crypt filter (%d %d R)", pdf_to_num(obj), pdf_to_gen(obj)); } /* in crypt revision 4, the crypt filter determines the key length */ @@ -155,36 +155,46 @@ pdf_new_crypt(fz_context *ctx, fz_obj *dict, fz_obj *id) /* Standard security handler (PDF 1.7 table 3.19) */ - obj = fz_dict_gets(dict, "R"); - if (fz_is_int(obj)) - crypt->r = fz_to_int(obj); + obj = pdf_dict_gets(dict, "R"); + if (pdf_is_int(obj)) + crypt->r = pdf_to_int(obj); + else if (crypt->v <= 4) + { + fz_warn(ctx, "encryption dictionary missing revision value, guessing..."); + if (crypt->v < 2) + crypt->r = 2; + else if (crypt->v == 2 || crypt->v == 3) + crypt->r = 3; + else if (crypt->v == 4) + crypt->r = 4; + } else { pdf_free_crypt(ctx, crypt); - fz_throw(ctx, "encryption dictionary missing revision value"); + fz_throw(ctx, "encryption dictionary missing version and revision value"); } - obj = fz_dict_gets(dict, "O"); - if (fz_is_string(obj) && fz_to_str_len(obj) == 32) - memcpy(crypt->o, fz_to_str_buf(obj), 32); + obj = pdf_dict_gets(dict, "O"); + if (pdf_is_string(obj) && pdf_to_str_len(obj) == 32) + memcpy(crypt->o, pdf_to_str_buf(obj), 32); /* /O and /U are supposed to be 48 bytes long for revision 5, they're often longer, though */ - else if (crypt->r == 5 && fz_is_string(obj) && fz_to_str_len(obj) >= 48) - memcpy(crypt->o, fz_to_str_buf(obj), 48); + else if (crypt->r == 5 && pdf_is_string(obj) && pdf_to_str_len(obj) >= 48) + memcpy(crypt->o, pdf_to_str_buf(obj), 48); else { pdf_free_crypt(ctx, crypt); fz_throw(ctx, "encryption dictionary missing owner password"); } - obj = fz_dict_gets(dict, "U"); - if (fz_is_string(obj) && fz_to_str_len(obj) == 32) - memcpy(crypt->u, fz_to_str_buf(obj), 32); - else if (fz_is_string(obj) && fz_to_str_len(obj) >= 48 && crypt->r == 5) - memcpy(crypt->u, fz_to_str_buf(obj), 48); - else if (fz_is_string(obj) && fz_to_str_len(obj) < 32) + obj = pdf_dict_gets(dict, "U"); + if (pdf_is_string(obj) && pdf_to_str_len(obj) == 32) + memcpy(crypt->u, pdf_to_str_buf(obj), 32); + else if (pdf_is_string(obj) && pdf_to_str_len(obj) >= 48 && crypt->r == 5) + memcpy(crypt->u, pdf_to_str_buf(obj), 48); + else if (pdf_is_string(obj) && pdf_to_str_len(obj) < 32) { - fz_warn(ctx, "encryption password key too short (%d)", fz_to_str_len(obj)); - memcpy(crypt->u, fz_to_str_buf(obj), fz_to_str_len(obj)); + fz_warn(ctx, "encryption password key too short (%d)", pdf_to_str_len(obj)); + memcpy(crypt->u, pdf_to_str_buf(obj), pdf_to_str_len(obj)); } else { @@ -192,46 +202,46 @@ pdf_new_crypt(fz_context *ctx, fz_obj *dict, fz_obj *id) fz_throw(ctx, "encryption dictionary missing user password"); } - obj = fz_dict_gets(dict, "P"); - if (fz_is_int(obj)) - crypt->p = fz_to_int(obj); + obj = pdf_dict_gets(dict, "P"); + if (pdf_is_int(obj)) + crypt->p = pdf_to_int(obj); else { - pdf_free_crypt(ctx, crypt); - fz_throw(ctx, "encryption dictionary missing permissions value"); + fz_warn(ctx, "encryption dictionary missing permissions"); + crypt->p = 0xfffffffc; } if (crypt->r == 5) { - obj = fz_dict_gets(dict, "OE"); - if (!fz_is_string(obj) || fz_to_str_len(obj) != 32) + obj = pdf_dict_gets(dict, "OE"); + if (!pdf_is_string(obj) || pdf_to_str_len(obj) != 32) { pdf_free_crypt(ctx, crypt); fz_throw(ctx, "encryption dictionary missing owner encryption key"); } - memcpy(crypt->oe, fz_to_str_buf(obj), 32); + memcpy(crypt->oe, pdf_to_str_buf(obj), 32); - obj = fz_dict_gets(dict, "UE"); - if (!fz_is_string(obj) || fz_to_str_len(obj) != 32) + obj = pdf_dict_gets(dict, "UE"); + if (!pdf_is_string(obj) || pdf_to_str_len(obj) != 32) { pdf_free_crypt(ctx, crypt); fz_throw(ctx, "encryption dictionary missing user encryption key"); } - memcpy(crypt->ue, fz_to_str_buf(obj), 32); + memcpy(crypt->ue, pdf_to_str_buf(obj), 32); } crypt->encrypt_metadata = 1; - obj = fz_dict_gets(dict, "EncryptMetadata"); - if (fz_is_bool(obj)) - crypt->encrypt_metadata = fz_to_bool(obj); + obj = pdf_dict_gets(dict, "EncryptMetadata"); + if (pdf_is_bool(obj)) + crypt->encrypt_metadata = pdf_to_bool(obj); /* Extract file identifier string */ - if (fz_is_array(id) && fz_array_len(id) == 2) + if (pdf_is_array(id) && pdf_array_len(id) == 2) { - obj = fz_array_get(id, 0); - if (fz_is_string(obj)) - crypt->id = fz_keep_obj(obj); + obj = pdf_array_get(id, 0); + if (pdf_is_string(obj)) + crypt->id = pdf_keep_obj(obj); } else fz_warn(ctx, "missing file identifier, may not be able to do decryption"); @@ -242,8 +252,8 @@ pdf_new_crypt(fz_context *ctx, fz_obj *dict, fz_obj *id) void pdf_free_crypt(fz_context *ctx, pdf_crypt *crypt) { - if (crypt->id) fz_drop_obj(crypt->id); - if (crypt->cf) fz_drop_obj(crypt->cf); + if (crypt->id) pdf_drop_obj(crypt->id); + if (crypt->cf) pdf_drop_obj(crypt->cf); fz_free(ctx, crypt); } @@ -252,15 +262,15 @@ pdf_free_crypt(fz_context *ctx, pdf_crypt *crypt) */ static void -pdf_parse_crypt_filter(fz_context *ctx, pdf_crypt_filter *cf, fz_obj *cf_obj, char *name, int defaultlength) +pdf_parse_crypt_filter(fz_context *ctx, pdf_crypt_filter *cf, pdf_obj *cf_obj, char *name, int defaultlength) { - fz_obj *obj; - fz_obj *dict; + pdf_obj *obj; + pdf_obj *dict; int is_identity = (strcmp(name, "Identity") == 0); int is_stdcf = (!is_identity && (strcmp(name, "StdCF") == 0)); if (!is_identity && !is_stdcf) - fz_throw(ctx, "Crypt Filter not Identity or StdCF (%d %d R)", fz_to_num(cf_obj), fz_to_gen(cf_obj)); + fz_throw(ctx, "Crypt Filter not Identity or StdCF (%d %d R)", pdf_to_num(cf_obj), pdf_to_gen(cf_obj)); cf->method = PDF_CRYPT_NONE; cf->length = defaultlength; @@ -271,28 +281,28 @@ pdf_parse_crypt_filter(fz_context *ctx, pdf_crypt_filter *cf, fz_obj *cf_obj, ch return; } - dict = fz_dict_gets(cf_obj, name); - if (!fz_is_dict(dict)) - fz_throw(ctx, "cannot parse crypt filter (%d %d R)", fz_to_num(cf_obj), fz_to_gen(cf_obj)); + dict = pdf_dict_gets(cf_obj, name); + if (!pdf_is_dict(dict)) + fz_throw(ctx, "cannot parse crypt filter (%d %d R)", pdf_to_num(cf_obj), pdf_to_gen(cf_obj)); - obj = fz_dict_gets(dict, "CFM"); - if (fz_is_name(obj)) + obj = pdf_dict_gets(dict, "CFM"); + if (pdf_is_name(obj)) { - if (!strcmp(fz_to_name(obj), "None")) + if (!strcmp(pdf_to_name(obj), "None")) cf->method = PDF_CRYPT_NONE; - else if (!strcmp(fz_to_name(obj), "V2")) + else if (!strcmp(pdf_to_name(obj), "V2")) cf->method = PDF_CRYPT_RC4; - else if (!strcmp(fz_to_name(obj), "AESV2")) + else if (!strcmp(pdf_to_name(obj), "AESV2")) cf->method = PDF_CRYPT_AESV2; - else if (!strcmp(fz_to_name(obj), "AESV3")) + else if (!strcmp(pdf_to_name(obj), "AESV3")) cf->method = PDF_CRYPT_AESV3; else - fz_warn(ctx, "unknown encryption method: %s", fz_to_name(obj)); + fz_warn(ctx, "unknown encryption method: %s", pdf_to_name(obj)); } - obj = fz_dict_gets(dict, "Length"); - if (fz_is_int(obj)) - cf->length = fz_to_int(obj); + obj = pdf_dict_gets(dict, "Length"); + if (pdf_is_int(obj)) + cf->length = pdf_to_int(obj); /* the length for crypt filters is supposed to be in bytes not bits */ if (cf->length < 40) @@ -346,7 +356,7 @@ pdf_compute_encryption_key(pdf_crypt *crypt, unsigned char *password, int pwlen, fz_md5_update(&md5, buf, 4); /* Step 5 - pass first element of ID array */ - fz_md5_update(&md5, (unsigned char *)fz_to_str_buf(crypt->id), fz_to_str_len(crypt->id)); + fz_md5_update(&md5, (unsigned char *)pdf_to_str_buf(crypt->id), pdf_to_str_len(crypt->id)); /* Step 6 (revision 4 or greater) - if metadata is not encrypted pass 0xFFFFFFFF */ if (crypt->r >= 4) @@ -455,7 +465,7 @@ pdf_compute_user_password(pdf_crypt *crypt, unsigned char *password, int pwlen, fz_md5_init(&md5); fz_md5_update(&md5, padding, 32); - fz_md5_update(&md5, (unsigned char*)fz_to_str_buf(crypt->id), fz_to_str_len(crypt->id)); + fz_md5_update(&md5, (unsigned char*)pdf_to_str_buf(crypt->id), pdf_to_str_len(crypt->id)); fz_md5_final(&md5, digest); fz_arc4_init(&arc4, crypt->key, n); @@ -608,7 +618,7 @@ pdf_has_permission(pdf_document *xref, int p) } unsigned char * -pdf_get_crypt_key(pdf_document *xref) +pdf_crypt_key(pdf_document *xref) { if (xref->crypt) return xref->crypt->key; @@ -616,7 +626,7 @@ pdf_get_crypt_key(pdf_document *xref) } int -pdf_get_crypt_revision(pdf_document *xref) +pdf_crypt_revision(pdf_document *xref) { if (xref->crypt) return xref->crypt->v; @@ -624,7 +634,7 @@ pdf_get_crypt_revision(pdf_document *xref) } char * -pdf_get_crypt_method(pdf_document *xref) +pdf_crypt_method(pdf_document *xref) { if (xref->crypt) { @@ -641,7 +651,7 @@ pdf_get_crypt_method(pdf_document *xref) } int -pdf_get_crypt_length(pdf_document *xref) +pdf_crypt_length(pdf_document *xref) { if (xref->crypt) return xref->crypt->length; @@ -697,18 +707,18 @@ pdf_compute_object_key(pdf_crypt *crypt, pdf_crypt_filter *cf, int num, int gen, */ static void -pdf_crypt_obj_imp(fz_context *ctx, pdf_crypt *crypt, fz_obj *obj, unsigned char *key, int keylen) +pdf_crypt_obj_imp(fz_context *ctx, pdf_crypt *crypt, pdf_obj *obj, unsigned char *key, int keylen) { unsigned char *s; int i, n; - if (fz_is_indirect(obj)) + if (pdf_is_indirect(obj)) return; - if (fz_is_string(obj)) + if (pdf_is_string(obj)) { - s = (unsigned char *)fz_to_str_buf(obj); - n = fz_to_str_len(obj); + s = (unsigned char *)pdf_to_str_buf(obj); + n = pdf_to_str_len(obj); if (crypt->strf.method == PDF_CRYPT_RC4) { @@ -736,32 +746,32 @@ pdf_crypt_obj_imp(fz_context *ctx, pdf_crypt *crypt, fz_obj *obj, unsigned char if (s[n - 17] < 1 || s[n - 17] > 16) fz_warn(ctx, "aes padding out of range"); else - fz_set_str_len(obj, n - 16 - s[n - 17]); + pdf_set_str_len(obj, n - 16 - s[n - 17]); } } } - else if (fz_is_array(obj)) + else if (pdf_is_array(obj)) { - n = fz_array_len(obj); + n = pdf_array_len(obj); for (i = 0; i < n; i++) { - pdf_crypt_obj_imp(ctx, crypt, fz_array_get(obj, i), key, keylen); + pdf_crypt_obj_imp(ctx, crypt, pdf_array_get(obj, i), key, keylen); } } - else if (fz_is_dict(obj)) + else if (pdf_is_dict(obj)) { - n = fz_dict_len(obj); + n = pdf_dict_len(obj); for (i = 0; i < n; i++) { - pdf_crypt_obj_imp(ctx, crypt, fz_dict_get_val(obj, i), key, keylen); + pdf_crypt_obj_imp(ctx, crypt, pdf_dict_get_val(obj, i), key, keylen); } } } void -pdf_crypt_obj(fz_context *ctx, pdf_crypt *crypt, fz_obj *obj, int num, int gen) +pdf_crypt_obj(fz_context *ctx, pdf_crypt *crypt, pdf_obj *obj, int num, int gen) { unsigned char key[32]; int len; @@ -812,7 +822,7 @@ pdf_open_crypt_with_filter(fz_stream *chain, pdf_crypt *crypt, char *name, int n return chain; } -void pdf_debug_crypt(pdf_crypt *crypt) +void pdf_print_crypt(pdf_crypt *crypt) { int i; |