Security-57031.1.35.tar.gz

[apple/security.git] / Security / libsecurity_codesigning / lib / cscdefs.h

diff --git a/Security/libsecurity_codesigning/lib/cscdefs.h b/Security/libsecurity_codesigning/lib/cscdefs.h
new file mode 100644 (file)
index 0000000..4c3b998
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+++ b/Security/libsecurity_codesigning/lib/cscdefs.h
@@ -0,0 +1,89 @@
+/*
+ * Magic numbers used by Code Signing
+ */
+enum {
+       CSMAGIC_REQUIREMENT     = 0xfade0c00,           /* single Requirement blob */
+       CSMAGIC_REQUIREMENTS = 0xfade0c01,              /* Requirements vector (internal requirements) */
+       CSMAGIC_CODEDIRECTORY = 0xfade0c02,             /* CodeDirectory blob */
+       CSMAGIC_EMBEDDED_SIGNATURE = 0xfade0cc0, /* embedded form of signature data */
+       CSMAGIC_DETACHED_SIGNATURE = 0xfade0cc1, /* multi-arch collection of embedded signatures */
+       
+       CSSLOT_CODEDIRECTORY = 0,                               /* slot index for CodeDirectory */
+};
+
+
+/*
+ * Structure of an embedded-signature SuperBlob
+ */
+typedef struct __BlobIndex {
+       uint32_t type;                                  /* type of entry */
+       uint32_t offset;                                /* offset of entry */
+} CS_BlobIndex;
+
+typedef struct __SuperBlob {
+       uint32_t magic;                                 /* magic number */
+       uint32_t length;                                /* total length of SuperBlob */
+       uint32_t count;                                 /* number of index entries following */
+       CS_BlobIndex index[];                   /* (count) entries */
+       /* followed by Blobs in no particular order as indicated by offsets in index */
+} CS_SuperBlob;
+
+
+/*
+ * C form of a CodeDirectory.
+ */
+typedef struct __CodeDirectory {
+       uint32_t magic;                                 /* magic number (CSMAGIC_CODEDIRECTORY) */
+       uint32_t length;                                /* total length of CodeDirectory blob */
+       uint32_t version;                               /* compatibility version */
+       uint32_t flags;                                 /* setup and mode flags */
+       uint32_t hashOffset;                    /* offset of hash slot element at index zero */
+       uint32_t identOffset;                   /* offset of identifier string */
+       uint32_t nSpecialSlots;                 /* number of special hash slots */
+       uint32_t nCodeSlots;                    /* number of ordinary (code) hash slots */
+       uint32_t codeLimit;                             /* limit to main image signature range */
+       uint8_t hashSize;                               /* size of each hash in bytes */
+       uint8_t hashType;                               /* type of hash (cdHashType* constants) */
+       uint8_t spare1;                                 /* unused (must be zero) */
+       uint8_t pageSize;                               /* log2(page size in bytes); 0 => infinite */
+       uint32_t spare2;                                /* unused (must be zero) */
+       /* followed by dynamic content as located by offset fields above */
+} CS_CodeDirectory;
+
+
+/*
+ * Sample code to locate the CodeDirectory from an embedded signature blob
+ */
+static inline const CS_CodeDirectory *findCodeDirectory(const CS_SuperBlob *embedded)
+{
+       if (embedded && ntohl(embedded->magic) == CSMAGIC_EMBEDDED_SIGNATURE) {
+               const CS_BlobIndex *limit = &embedded->index[ntohl(embedded->count)];
+               const CS_BlobIndex *p;
+               for (p = embedded->index; p < limit; ++p)
+                       if (ntohl(p->type) == CSSLOT_CODEDIRECTORY) {
+                               const unsigned char *base = (const unsigned char *)embedded;
+                               const CS_CodeDirectory *cd = (const CS_CodeDirectory *)(base + ntohl(p->offset));
+                               if (cd->magic == CSMAGIC_CODEDIRECTORY)
+                                       return cd;
+                               else
+                                       break;
+                       }
+       }
+       // not found
+       return NULL;
+}
+
+
+/*
+ * Locating a page hash
+ */
+static inline const unsigned char *hashes(const CS_CodeDirectory *cd, unsigned page)
+{
+       const unsigned char *base = (const unsigned char *)cd;
+       assert(page < ntohl(cd->nCodeSlots));
+       
+       // "20" below is the size of a SHA-1 hash. There's got to be a constant for that
+       // where you get your SHA-1 functions from. This can also be had as cd->hashSize
+       // (but the constant is marginally faster, I suppose)
+       return base + ntohl(cd->hashOffset) + page * 20;
+}