remove retouching code from updater

Removes the retouch_binaries and undo_retouch_binaries from updater;
newly generated OTA packages should not call them any more.

Note that applypatch retains the ability to unretouch a file as it
reads it.  This will be needed as long as we want to support OTAs from
devices that were installed with retouching.

Change-Id: Ib3f6baeae90c84ba85983f626d821ab7e436ceb2

3 files changed, 0 insertions, 334 deletions

diff --git a/minelf/Retouch.c b/minelf/Retouch.c
index a25380b..d75eec1 100644
--- a/minelf/Retouch.c
+++ b/minelf/Retouch.c
@@ -194,213 +194,3 @@ int retouch_mask_data(uint8_t *binary_object,
     if (retouch_offset != NULL) *retouch_offset = offset_candidate;
     return RETOUCH_DATA_MATCHED;
 }
-
-// On success, _override is set to the offset that was actually applied.
-// This implies that once we randomize to an offset we stick with it.
-// This in turn is necessary in order to guarantee recovery after crash.
-bool retouch_one_library(const char *binary_name,
-                         const char *binary_sha1,
-                         int32_t retouch_offset,
-                         int32_t *retouch_offset_override) {
-    bool success = true;
-    int result;
-
-    FileContents file;
-    file.data = NULL;
-
-    char binary_name_atomic[strlen(binary_name)+10];
-    strcpy(binary_name_atomic, binary_name);
-    strcat(binary_name_atomic, ".atomic");
-
-    // We need a path that exists for calling statfs() later.
-    //
-    // Assume that binary_name (eg "/system/app/Foo.apk") is located
-    // on the same filesystem as its top-level directory ("/system").
-    char target_fs[strlen(binary_name)+1];
-    char* slash = strchr(binary_name+1, '/');
-    if (slash != NULL) {
-        int count = slash - binary_name;
-        strncpy(target_fs, binary_name, count);
-        target_fs[count] = '\0';
-    } else {
-        strcpy(target_fs, binary_name);
-    }
-
-    result = LoadFileContents(binary_name, &file, RETOUCH_DONT_MASK);
-
-    if (result == 0) {
-        // Figure out the *apparent* offset to which this file has been
-        // retouched. If it looks good, we will skip processing (we might
-        // have crashed and during this recovery pass we don't want to
-        // overwrite a valuable saved file in /cache---which would happen
-        // if we blindly retouch everything again). NOTE: This implies
-        // that we might have to override the supplied retouch offset. We
-        // can do the override only once though: everything should match
-        // afterward.
-
-        int32_t inferred_offset;
-        int retouch_probe_result = retouch_mask_data(file.data,
-                                                     file.size,
-                                                     NULL,
-                                                     &inferred_offset);
-
-        if (retouch_probe_result == RETOUCH_DATA_MATCHED) {
-            if ((retouch_offset == inferred_offset) ||
-                ((retouch_offset != 0 && inferred_offset != 0) &&
-                 (retouch_offset_override != NULL))) {
-                // This file is OK already and we are allowed to override.
-                // Let's just return the offset override value. It is critical
-                // to skip regardless of override: a broken file might need
-                // recovery down the list and we should not mess up the saved
-                // copy by doing unnecessary retouching.
-                //
-                // NOTE: If retouching was already started with a different
-                // value, we will not be allowed to override. This happens
-                // if on the retouch list there is a patched binary (which is
-                // masked in apply_patch()) before there is a non-patched
-                // binary.
-                if (retouch_offset_override != NULL)
-                    *retouch_offset_override = inferred_offset;
-                success = true;
-                goto out;
-            } else {
-                // Retouch to zero (mask the retouching), to make sure that
-                // the SHA-1 check will pass below.
-                int32_t zero = 0;
-                retouch_mask_data(file.data, file.size, &zero, NULL);
-                SHA(file.data, file.size, file.sha1);
-            }
-        }
-
-        if (retouch_probe_result == RETOUCH_DATA_NOTAPPLICABLE) {
-            // In the case of not retouchable, fake it. We do not want
-            // to do the normal processing and overwrite the backup file:
-            // we might be recovering!
-            //
-            // We return a zero override, which tells the caller that we
-            // simply skipped the file.
-            if (retouch_offset_override != NULL)
-                *retouch_offset_override = 0;
-            success = true;
-            goto out;
-        }
-
-        // If we get here, either there was a mismatch in the offset, or
-        // the file has not been processed yet. Continue with normal
-        // processing.
-    }
-
-    if (result != 0 || FindMatchingPatch(file.sha1, &binary_sha1, 1) < 0) {
-        free(file.data);
-        printf("Attempting to recover source from '%s' ...\n",
-               CACHE_TEMP_SOURCE);
-        result = LoadFileContents(CACHE_TEMP_SOURCE, &file, RETOUCH_DO_MASK);
-        if (result != 0 || FindMatchingPatch(file.sha1, &binary_sha1, 1) < 0) {
-            printf(" failed.\n");
-            success = false;
-            goto out;
-        }
-        printf(" succeeded.\n");
-    }
-
-    // Retouch in-memory before worrying about backing up the original.
-    //
-    // Recovery steps will be oblivious to the actual retouch offset used,
-    // so might as well write out the already-retouched copy. Then, in the
-    // usual case, we will just swap the file locally, with no more writes
-    // needed. In the no-free-space case, we will then write the same to the
-    // original location.
-
-    result = retouch_mask_data(file.data, file.size, &retouch_offset, NULL);
-    if (result != RETOUCH_DATA_MATCHED) {
-        success = false;
-        goto out;
-    }
-    if (retouch_offset_override != NULL)
-        *retouch_offset_override = retouch_offset;
-
-    // How much free space do we need?
-    bool enough_space = false;
-    size_t free_space = FreeSpaceForFile(target_fs);
-    // 50% margin when estimating the space needed.
-    enough_space = (free_space > (file.size * 3 / 2));
-
-    // The experts say we have to allow for a retry of the
-    // whole process to avoid filesystem weirdness.
-    int retry = 1;
-    bool made_copy = false;
-    do {
-        // First figure out where to store a copy of the original.
-        // Ideally leave the original itself intact until the
-        // atomic swap. If no room on the same partition, fall back
-        // to the cache partition and remove the original.
-
-        if (!enough_space) {
-            printf("Target is %ldB; free space is %ldB: not enough.\n",
-                   (long)file.size, (long)free_space);
-
-            retry = 0;
-            if (MakeFreeSpaceOnCache(file.size) < 0) {
-                printf("Not enough free space on '/cache'.\n");
-                success = false;
-                goto out;
-            }
-            if (SaveFileContents(CACHE_TEMP_SOURCE, &file) < 0) {
-                printf("Failed to back up source file.\n");
-                success = false;
-                goto out;
-            }
-            made_copy = true;
-            unlink(binary_name);
-
-            size_t free_space = FreeSpaceForFile(target_fs);
-            printf("(now %ld bytes free for target)\n", (long)free_space);
-        }
-
-        result = SaveFileContents(binary_name_atomic, &file);
-        if (result != 0) {
-            // Maybe the filesystem was optimistic: retry.
-            enough_space = false;
-            unlink(binary_name_atomic);
-            printf("Saving the retouched contents failed; retrying.\n");
-            continue;
-        }
-
-        // Succeeded; no need to retry.
-        break;
-    } while (retry-- > 0);
-
-    // Give the .atomic file the same owner, group, and mode of the
-    // original source file.
-    if (chmod(binary_name_atomic, file.st.st_mode) != 0) {
-        printf("chmod of \"%s\" failed: %s\n",
-               binary_name_atomic, strerror(errno));
-        success = false;
-        goto out;
-    }
-    if (chown(binary_name_atomic, file.st.st_uid, file.st.st_gid) != 0) {
-        printf("chown of \"%s\" failed: %s\n",
-               binary_name_atomic,
-               strerror(errno));
-        success = false;
-        goto out;
-    }
-
-    // Finally, rename the .atomic file to replace the target file.
-    if (rename(binary_name_atomic, binary_name) != 0) {
-        printf("rename of .atomic to \"%s\" failed: %s\n",
-               binary_name, strerror(errno));
-        success = false;
-        goto out;
-    }
-
-    // If this run created a copy, and we're here, we can delete it.
-    if (made_copy) unlink(CACHE_TEMP_SOURCE);
-
-  out:
-    // clean up
-    free(file.data);
-    unlink(binary_name_atomic);
-
-    return success;
-}
diff --git a/minelf/Retouch.h b/minelf/Retouch.h
index 048d78e..13bacd5 100644
--- a/minelf/Retouch.h
+++ b/minelf/Retouch.h
@@ -25,12 +25,6 @@ typedef struct {
   uint32_t blob_size; /* in bytes, located right before this struct */
 } retouch_info_t __attribute__((packed));
 
-// Retouch a file. Use CACHED_SOURCE_TEMP to store a copy.
-bool retouch_one_library(const char *binary_name,
-                         const char *binary_sha1,
-                         int32_t retouch_offset,
-                         int32_t *retouch_offset_override);
-
 #define RETOUCH_DONT_MASK           0
 #define RETOUCH_DO_MASK             1
 
diff --git a/updater/install.c b/updater/install.c
index f68bd03..c087d4e 100644
--- a/updater/install.c
+++ b/updater/install.c
@@ -33,7 +33,6 @@
 #include "edify/expr.h"
 #include "mincrypt/sha.h"
 #include "minzip/DirUtil.h"
-#include "minelf/Retouch.h"
 #include "mtdutils/mounts.h"
 #include "mtdutils/mtdutils.h"
 #include "updater.h"
@@ -435,121 +434,6 @@ Value* PackageExtractFileFn(const char* name, State* state,
 }
 
 
-// retouch_binaries(lib1, lib2, ...)
-Value* RetouchBinariesFn(const char* name, State* state,
-                         int argc, Expr* argv[]) {
-    UpdaterInfo* ui = (UpdaterInfo*)(state->cookie);
-
-    char **retouch_entries  = ReadVarArgs(state, argc, argv);
-    if (retouch_entries == NULL) {
-        return StringValue(strdup("t"));
-    }
-
-    // some randomness from the clock
-    int32_t override_base;
-    bool override_set = false;
-    int32_t random_base = time(NULL) % 1024;
-    // some more randomness from /dev/random
-    FILE *f_random = fopen("/dev/random", "rb");
-    uint16_t random_bits = 0;
-    if (f_random != NULL) {
-        fread(&random_bits, 2, 1, f_random);
-        random_bits = random_bits % 1024;
-        fclose(f_random);
-    }
-    random_base = (random_base + random_bits) % 1024;
-    fprintf(ui->cmd_pipe, "ui_print Random offset: 0x%x\n", random_base);
-    fprintf(ui->cmd_pipe, "ui_print\n");
-
-    // make sure we never randomize to zero; this let's us look at a file
-    // and know for sure whether it has been processed; important in the
-    // crash recovery process
-    if (random_base == 0) random_base = 1;
-    // make sure our randomization is page-aligned
-    random_base *= -0x1000;
-    override_base = random_base;
-
-    int i = 0;
-    bool success = true;
-    while (i < (argc - 1)) {
-        success = success && retouch_one_library(retouch_entries[i],
-                                                 retouch_entries[i+1],
-                                                 random_base,
-                                                 override_set ?
-                                                   NULL :
-                                                   &override_base);
-        if (!success)
-            ErrorAbort(state, "Failed to retouch '%s'.", retouch_entries[i]);
-
-        free(retouch_entries[i]);
-        free(retouch_entries[i+1]);
-        i += 2;
-
-        if (success && override_base != 0) {
-            random_base = override_base;
-            override_set = true;
-        }
-    }
-    if (i < argc) {
-        free(retouch_entries[i]);
-        success = false;
-    }
-    free(retouch_entries);
-
-    if (!success) {
-      Value* v = malloc(sizeof(Value));
-      v->type = VAL_STRING;
-      v->data = NULL;
-      v->size = -1;
-      return v;
-    }
-    return StringValue(strdup("t"));
-}
-
-
-// undo_retouch_binaries(lib1, lib2, ...)
-Value* UndoRetouchBinariesFn(const char* name, State* state,
-                             int argc, Expr* argv[]) {
-    UpdaterInfo* ui = (UpdaterInfo*)(state->cookie);
-
-    char **retouch_entries  = ReadVarArgs(state, argc, argv);
-    if (retouch_entries == NULL) {
-        return StringValue(strdup("t"));
-    }
-
-    int i = 0;
-    bool success = true;
-    int32_t override_base;
-    while (i < (argc-1)) {
-        success = success && retouch_one_library(retouch_entries[i],
-                                                 retouch_entries[i+1],
-                                                 0 /* undo => offset==0 */,
-                                                 NULL);
-        if (!success)
-            ErrorAbort(state, "Failed to unretouch '%s'.",
-                       retouch_entries[i]);
-
-        free(retouch_entries[i]);
-        free(retouch_entries[i+1]);
-        i += 2;
-    }
-    if (i < argc) {
-        free(retouch_entries[i]);
-        success = false;
-    }
-    free(retouch_entries);
-
-    if (!success) {
-      Value* v = malloc(sizeof(Value));
-      v->type = VAL_STRING;
-      v->data = NULL;
-      v->size = -1;
-      return v;
-    }
-    return StringValue(strdup("t"));
-}
-
-
 // symlink target src1 src2 ...
 //    unlinks any previously existing src1, src2, etc before creating symlinks.
 Value* SymlinkFn(const char* name, State* state, int argc, Expr* argv[]) {
@@ -1190,8 +1074,6 @@ void RegisterInstallFunctions() {
     RegisterFunction("delete_recursive", DeleteFn);
     RegisterFunction("package_extract_dir", PackageExtractDirFn);
     RegisterFunction("package_extract_file", PackageExtractFileFn);
-    RegisterFunction("retouch_binaries", RetouchBinariesFn);
-    RegisterFunction("undo_retouch_binaries", UndoRetouchBinariesFn);
     RegisterFunction("symlink", SymlinkFn);
     RegisterFunction("set_perm", SetPermFn);
     RegisterFunction("set_perm_recursive", SetPermFn);