imapfilter/imapfilter/passwd.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>

#include "config.h"
#include "imapfilter.h"
#include "data.h"

#ifdef ENCRYPTED_PASSWORDS
#include <openssl/evp.h>
#endif


extern unsigned int flags;
extern account_t *accounts;

#ifdef ENCRYPTED_PASSWORDS
extern char *passphr;

#endif

/*
 * Get password from user interactively.
 */
void
get_password(char *passwd, size_t pwlen)
{
        char *c;

        tty_disable_echo();

        if (fgets(passwd, pwlen, stdin))
                if ((c = strchr(passwd, '\n')))
                        *c = '\0';

        tty_restore();

        putchar('\n');
}


#ifdef ENCRYPTED_PASSWORDS
/*
 * Encrypt and Base64 encode passwords.  Append the MD5 checksum of the
 * passwords before encrypting them.
 */
int
encrypt_passwords(FILE * fd, account_t * accts[])
{
        int i;
        char *c;
        unsigned char iv[EVP_MAX_IV_LENGTH];
        unsigned char *key;
        unsigned char buf[ENCRYPTION_BUF];
        unsigned char ebuf[ENCRYPTION_BUF];
        unsigned char bbuf[ENCRYPTION_BUF];
        unsigned char mdv[EVP_MAX_MD_SIZE];
        int mdl, ebufl, bbufl;
        EVP_CIPHER_CTX ctx;
        EVP_MD_CTX mdctx;
        EVP_ENCODE_CTX bctx;

        key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);

        srandom(time(NULL));

        /* Initialization vector. */
        c = ultostr(1 + random() % 100000000, 10);
        snprintf(iv, EVP_MAX_IV_LENGTH, "%.8s", c);
        fprintf(fd, "%s\n", iv);

        EVP_CIPHER_CTX_init(&ctx);

        EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr), 1,
            key, NULL);

        EVP_DigestInit(&mdctx, EVP_md5());
        EVP_EncryptInit(&ctx, EVP_bf_cbc(), key, iv);
        EVP_EncodeInit(&bctx);

        for (i = 0; accts[i] != NULL; i++) {
                snprintf(buf, ENCRYPTION_BUF, "%s %s %s\n", accts[i]->server,
                    accts[i]->username, accts[i]->password);

                EVP_DigestUpdate(&mdctx, buf, strlen(buf));
                EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
                EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);

                fwrite(bbuf, sizeof(char), bbufl, fd);
        }

        EVP_DigestFinal(&mdctx, mdv, &mdl);

        xstrncpy(buf, ".\n", ENCRYPTION_BUF - 1);

        /* MD5 checksum of data. */
        for (i = 0; i < mdl; i++)
                snprintf(2 + buf + i * 2, ENCRYPTION_BUF - 3 - i * 2, "%02x",
                    mdv[i]);

        EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
        EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_EncryptFinal(&ctx, ebuf, &ebufl);

        EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_EncodeFinal(&bctx, bbuf, &bbufl);
        fwrite(bbuf, sizeof(char), bbufl, fd);

        EVP_CIPHER_CTX_cleanup(&ctx);

        return 0;
}


/*
 * Decode (Base64) passwords, decrypt them and verify the MD5 checksum.
 */
int
decrypt_passwords(unsigned char **buf, FILE * fd)
{
        int i, j;
        unsigned char iv[EVP_MAX_IV_LENGTH];
        unsigned char *key;
        unsigned char *c;
        unsigned char ebuf[LINE_MAX];
        unsigned char bbuf[LINE_MAX];
        unsigned char mdv[EVP_MAX_MD_SIZE];
        unsigned char mdc[EVP_MAX_MD_SIZE * 2 + 1];
        int mdl, bufl, ebufl;
        EVP_CIPHER_CTX *ctx;
        EVP_MD_CTX mdctx;
        EVP_ENCODE_CTX bctx;

        j = 1;

        c = *buf = (unsigned char *)smalloc(DECRYPTION_BUF * sizeof(char));
        key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
        ctx = (EVP_CIPHER_CTX *) smalloc(sizeof(EVP_CIPHER_CTX));

        fgets(bbuf, LINE_MAX, fd);

        memcpy(iv, bbuf, EVP_MAX_IV_LENGTH);

        EVP_CIPHER_CTX_init(ctx);

        EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr),
            1, key, NULL);

        EVP_DecryptInit(ctx, EVP_bf_cbc(), key, iv);
        EVP_DecodeInit(&bctx);

        while (fgets(bbuf, LINE_MAX, fd)) {
                EVP_DecodeUpdate(&bctx, ebuf, &ebufl, bbuf, strlen(bbuf));
                if (!EVP_DecryptUpdate(ctx, c, &bufl, ebuf, ebufl))
                        goto fail;

                c += bufl;
                *c = '\0';

                if (c - *buf > DECRYPTION_BUF * j - 64) {
                        i = c - *buf;
                        *buf = (char *)srealloc(*buf, DECRYPTION_BUF * ++j);
                        c = *buf + i;
                        *c = '\0';
                }
        }

        EVP_DecodeFinal(&bctx, ebuf, &ebufl);
        if (!EVP_DecryptFinal(ctx, c, &bufl))
                goto fail;

        c += bufl;
        *c = '\0';

        /* Calculate the MD5 checksum and check if it is correct. */
        if (!(c = strstr(*buf, "\n.\n")))
                goto fail;

        EVP_DigestInit(&mdctx, EVP_md5());
        EVP_DigestUpdate(&mdctx, *buf, c - *buf + 1);
        EVP_DigestFinal(&mdctx, mdv, &mdl);

        for (i = 0; i < mdl; i++)
                snprintf(mdc + i * 2, EVP_MAX_MD_SIZE * 2 + 1 - i * 2, "%02x",
                    mdv[i]);

        c += 3;

        if (strncmp(c, mdc, 32))
                goto fail;

        EVP_CIPHER_CTX_cleanup(ctx);

        sfree(key);
        sfree(ctx);

        return 0;

fail:
        error("Wrong master passphrase.\n");
        EVP_CIPHER_CTX_cleanup(ctx);
        sfree(*buf);
        sfree(key);
        sfree(ctx);

        return ERROR_DECRYPT;
}


/*
 * Interactive encrypted passwords editor.
 */
void
password_editor(void)
{
        int i, q, n;
        char buf[LINE_MAX];
        char *c;
        char *p[2];
        account_t *a, *accts[EDITOR_PASSWORDS_MAX + 1];

        if (!(flags & FLAG_BLANK_PASSWORD)) {
                error("no candidate passwords for encryption found\n");
                return;
        }
        q = 0;

        memset(accts, 0, (EDITOR_PASSWORDS_MAX + 1) * sizeof(account_t *));

        for (i = 0, a = accounts; i < EDITOR_PASSWORDS_MAX && a != NULL;
            a = a->next) {
                if (a->passwdattr == PASSWORD_NONE ||
                    a->passwdattr == PASSWORD_ENCRYPTED)
                        accts[i++] = a;
        }

        do {
                printf("cmd: ");
                fgets(buf, LINE_MAX, stdin);
                c = buf;
                for (;; c++) {
                        if (*c == ' ' || *c == '\t')
                                continue;
                        else if (*c == '?' || *c == 'h')
                                printf("c\tclear a password entry\n"
                                    "e\tedit a password entry\n"
                                    "h\thelp\n"
                                    "l\tlist entries\n"
                                    "p\tchange master password\n"
                                    "q\tquit without saving\n"
                                    "s\tsave changes\n"
                                    "x\tsave and exit\n");
                        else if (*c == 'q')
                                q = 1;
                        else if (*c == 'l')
                                for (i = 0; accts[i] != NULL; i++)
                                        printf("%d %s %s %s\n", i + 1,
                                            accts[i]->server,
                                            accts[i]->username,
                                            accts[i]->password);
                        else if (*c == 'e') {
                                n = atoi(++c);
                                if (n == 0 || n < 1 ||
                                    n > EDITOR_PASSWORDS_MAX ||
                                    accts[n - 1] == NULL)
                                        break;
                                accts[n - 1]->password[0] = '\0';
                                printf("Enter new password: ");
                                if (fgets(accts[n - 1]->password, PASSWORD_LEN,
                                        stdin) &&
                                    (c = strchr(accts[n - 1]->password, '\n')))
                                        *c = '\0';
                        } else if (*c == 'c') {
                                n = atoi(++c);
                                if (n == 0 || n < 1 ||
                                    n > EDITOR_PASSWORDS_MAX ||
                                    accts[n - 1] == NULL)
                                        break;
                                accts[n - 1]->password[0] = '\0';
                        } else if (*c == 'p') {
                                p[0] = (char *)smalloc(PASSPHRASE_LEN);
                                p[1] = (char *)smalloc(PASSPHRASE_LEN);
                                do {
                                        for (i = 0; i < 2; i++) {
                                                printf("Enter %snew master "
                                                    "password: ",
                                                    i ? "again " : "");
                                                get_password(p[i],
                                                    PASSPHRASE_LEN);
                                        }
                                } while (strcmp(p[0], p[1]));
                                xstrncpy(passphr, p[0], PASSPHRASE_LEN - 1);
                                sfree(p[0]);
                                sfree(p[1]);
                        } else if (*c == 's' || *c == 'w') {
                                store_passwords(accts);
                        } else if (*c == 'x') {
                                store_passwords(accts);
                                q = 1;
                        } else
                                break;
                }
        } while (!q);
}

#endif                          /* ENCRYPTED_PASSWORDS */
1	lefcha	1.1	#include <stdio.h>
2			#include <string.h>
3	lefcha	1.2	#include <stdlib.h>
4			#include <limits.h>
5	lefcha	1.1
6	lefcha	1.2	#include "config.h"
7	lefcha	1.1	#include "imapfilter.h"
8			#include "data.h"
9
10	lefcha	1.2	#ifdef ENCRYPTED_PASSWORDS
11			#include <openssl/evp.h>
12			#endif
13	lefcha	1.1
14
15	lefcha	1.5	extern unsigned int flags;
16	lefcha	1.2	extern account_t *accounts;
17
18			#ifdef ENCRYPTED_PASSWORDS
19	lefcha	1.3	extern char *passphr;
20	lefcha	1.9
21	lefcha	1.2	#endif
22	lefcha	1.1
23			/*
24			* Get password from user interactively.
25			*/
26	lefcha	1.9	void
27			get_password(char *passwd, size_t pwlen)
28	lefcha	1.1	{
29	lefcha	1.9	char *c;
30	lefcha	1.2
31	lefcha	1.9	tty_disable_echo();
32	lefcha	1.8
33	lefcha	1.9	if (fgets(passwd, pwlen, stdin))
34			if ((c = strchr(passwd, '\n')))
35			*c = '\0';
36	lefcha	1.2
37	lefcha	1.9	tty_restore();
38	lefcha	1.1
39	lefcha	1.9	putchar('\n');
40	lefcha	1.1	}
41
42
43	lefcha	1.2	#ifdef ENCRYPTED_PASSWORDS
44	lefcha	1.1	/*
45	lefcha	1.9	* Encrypt and Base64 encode passwords. Append the MD5 checksum of the
46			* passwords before encrypting them.
47	lefcha	1.1	*/
48	lefcha	1.9	int
49			encrypt_passwords(FILE * fd, account_t * accts[])
50	lefcha	1.1	{
51	lefcha	1.9	int i;
52			char *c;
53			unsigned char iv[EVP_MAX_IV_LENGTH];
54			unsigned char *key;
55			unsigned char buf[ENCRYPTION_BUF];
56			unsigned char ebuf[ENCRYPTION_BUF];
57			unsigned char bbuf[ENCRYPTION_BUF];
58			unsigned char mdv[EVP_MAX_MD_SIZE];
59			int mdl, ebufl, bbufl;
60			EVP_CIPHER_CTX ctx;
61			EVP_MD_CTX mdctx;
62			EVP_ENCODE_CTX bctx;
63
64			key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
65
66			srandom(time(NULL));
67
68			/* Initialization vector. */
69			c = ultostr(1 + random() % 100000000, 10);
70	lefcha	1.11	snprintf(iv, EVP_MAX_IV_LENGTH, "%.8s", c);
71			fprintf(fd, "%s\n", iv);
72	lefcha	1.9
73			EVP_CIPHER_CTX_init(&ctx);
74
75			EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr), 1,
76			key, NULL);
77
78			EVP_DigestInit(&mdctx, EVP_md5());
79			EVP_EncryptInit(&ctx, EVP_bf_cbc(), key, iv);
80			EVP_EncodeInit(&bctx);
81
82			for (i = 0; accts[i] != NULL; i++) {
83			snprintf(buf, ENCRYPTION_BUF, "%s %s %s\n", accts[i]->server,
84			accts[i]->username, accts[i]->password);
85
86			EVP_DigestUpdate(&mdctx, buf, strlen(buf));
87			EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
88			EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
89	lefcha	1.2
90	lefcha	1.9	fwrite(bbuf, sizeof(char), bbufl, fd);
91			}
92	lefcha	1.6
93	lefcha	1.9	EVP_DigestFinal(&mdctx, mdv, &mdl);
94	lefcha	1.2
95	lefcha	1.9	xstrncpy(buf, ".\n", ENCRYPTION_BUF - 1);
96	lefcha	1.8
97	lefcha	1.9	/* MD5 checksum of data. */
98			for (i = 0; i < mdl; i++)
99	lefcha	1.11	snprintf(2 + buf + i * 2, ENCRYPTION_BUF - 3 - i * 2, "%02x",
100	lefcha	1.9	mdv[i]);
101	lefcha	1.8
102	lefcha	1.9	EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf));
103			EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
104			fwrite(bbuf, sizeof(char), bbufl, fd);
105	lefcha	1.8
106	lefcha	1.9	EVP_EncryptFinal(&ctx, ebuf, &ebufl);
107	lefcha	1.11
108	lefcha	1.9	EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl);
109	lefcha	1.11	fwrite(bbuf, sizeof(char), bbufl, fd);
110
111	lefcha	1.9	EVP_EncodeFinal(&bctx, bbuf, &bbufl);
112			fwrite(bbuf, sizeof(char), bbufl, fd);
113	lefcha	1.8
114	lefcha	1.9	EVP_CIPHER_CTX_cleanup(&ctx);
115	lefcha	1.2
116	lefcha	1.9	return 0;
117	lefcha	1.1	}
118
119
120			/*
121	lefcha	1.3	* Decode (Base64) passwords, decrypt them and verify the MD5 checksum.
122	lefcha	1.1	*/
123	lefcha	1.9	int
124			decrypt_passwords(unsigned char *buf, FILE fd)
125	lefcha	1.1	{
126	lefcha	1.9	int i, j;
127			unsigned char iv[EVP_MAX_IV_LENGTH];
128			unsigned char *key;
129			unsigned char *c;
130			unsigned char ebuf[LINE_MAX];
131			unsigned char bbuf[LINE_MAX];
132			unsigned char mdv[EVP_MAX_MD_SIZE];
133			unsigned char mdc[EVP_MAX_MD_SIZE * 2 + 1];
134			int mdl, bufl, ebufl;
135			EVP_CIPHER_CTX *ctx;
136			EVP_MD_CTX mdctx;
137			EVP_ENCODE_CTX bctx;
138
139			j = 1;
140
141			c = buf = (unsigned char )smalloc(DECRYPTION_BUF * sizeof(char));
142			key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH);
143			ctx = (EVP_CIPHER_CTX *) smalloc(sizeof(EVP_CIPHER_CTX));
144
145			fgets(bbuf, LINE_MAX, fd);
146
147			memcpy(iv, bbuf, EVP_MAX_IV_LENGTH);
148
149			EVP_CIPHER_CTX_init(ctx);
150
151			EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr),
152			1, key, NULL);
153
154			EVP_DecryptInit(ctx, EVP_bf_cbc(), key, iv);
155			EVP_DecodeInit(&bctx);
156
157			while (fgets(bbuf, LINE_MAX, fd)) {
158			EVP_DecodeUpdate(&bctx, ebuf, &ebufl, bbuf, strlen(bbuf));
159			if (!EVP_DecryptUpdate(ctx, c, &bufl, ebuf, ebufl))
160			goto fail;
161
162			c += bufl;
163			*c = '\0';
164
165			if (c - buf > DECRYPTION_BUF j - 64) {
166			i = c - *buf;
167			buf = (char )srealloc(buf, DECRYPTION_BUF ++j);
168			c = *buf + i;
169			*c = '\0';
170			}
171	lefcha	1.6	}
172	lefcha	1.8
173	lefcha	1.9	EVP_DecodeFinal(&bctx, ebuf, &ebufl);
174			if (!EVP_DecryptFinal(ctx, c, &bufl))
175			goto fail;
176	lefcha	1.2
177	lefcha	1.9	c += bufl;
178			*c = '\0';
179	lefcha	1.6
180	lefcha	1.9	/* Calculate the MD5 checksum and check if it is correct. */
181			if (!(c = strstr(*buf, "\n.\n")))
182			goto fail;
183	lefcha	1.6
184	lefcha	1.9	EVP_DigestInit(&mdctx, EVP_md5());
185			EVP_DigestUpdate(&mdctx, buf, c - buf + 1);
186			EVP_DigestFinal(&mdctx, mdv, &mdl);
187	lefcha	1.8
188	lefcha	1.9	for (i = 0; i < mdl; i++)
189			snprintf(mdc + i * 2, EVP_MAX_MD_SIZE * 2 + 1 - i * 2, "%02x",
190			mdv[i]);
191	lefcha	1.8
192	lefcha	1.9	c += 3;
193	lefcha	1.6
194	lefcha	1.9	if (strncmp(c, mdc, 32))
195			goto fail;
196	lefcha	1.2
197	lefcha	1.9	EVP_CIPHER_CTX_cleanup(ctx);
198	lefcha	1.8
199	lefcha	1.9	sfree(key);
200			sfree(ctx);
201	lefcha	1.8
202	lefcha	1.9	return 0;
203	lefcha	1.6
204			fail:
205	lefcha	1.9	error("Wrong master passphrase.\n");
206			EVP_CIPHER_CTX_cleanup(ctx);
207			sfree(*buf);
208			sfree(key);
209			sfree(ctx);
210	lefcha	1.8
211	lefcha	1.9	return ERROR_DECRYPT;
212	lefcha	1.2	}
213
214
215			/*
216			* Interactive encrypted passwords editor.
217			*/
218	lefcha	1.9	void
219			password_editor(void)
220	lefcha	1.2	{
221	lefcha	1.9	int i, q, n;
222			char buf[LINE_MAX];
223			char *c;
224			char *p[2];
225	lefcha	1.11	account_t a, accts[EDITOR_PASSWORDS_MAX + 1];
226	lefcha	1.9
227			if (!(flags & FLAG_BLANK_PASSWORD)) {
228			error("no candidate passwords for encryption found\n");
229			return;
230	lefcha	1.2	}
231	lefcha	1.9	q = 0;
232
233	lefcha	1.11	memset(accts, 0, (EDITOR_PASSWORDS_MAX + 1) * sizeof(account_t *));
234	lefcha	1.9
235	lefcha	1.11	for (i = 0, a = accounts; i < EDITOR_PASSWORDS_MAX && a != NULL;
236	lefcha	1.9	a = a->next) {
237			if (a->passwdattr == PASSWORD_NONE \|\|
238			a->passwdattr == PASSWORD_ENCRYPTED)
239			accts[i++] = a;
240			}
241
242			do {
243	lefcha	1.10	printf("cmd: ");
244	lefcha	1.9	fgets(buf, LINE_MAX, stdin);
245			c = buf;
246			for (;; c++) {
247			if (c == ' ' \|\| c == '\t')
248			continue;
249			else if (c == '?' \|\| c == 'h')
250			printf("c\tclear a password entry\n"
251			"e\tedit a password entry\n"
252			"h\thelp\n"
253			"l\tlist entries\n"
254			"p\tchange master password\n"
255			"q\tquit without saving\n"
256			"s\tsave changes\n"
257			"x\tsave and exit\n");
258			else if (*c == 'q')
259			q = 1;
260			else if (*c == 'l')
261			for (i = 0; accts[i] != NULL; i++)
262			printf("%d %s %s %s\n", i + 1,
263			accts[i]->server,
264			accts[i]->username,
265			accts[i]->password);
266			else if (*c == 'e') {
267			n = atoi(++c);
268	lefcha	1.11	if (n == 0 \|\| n < 1 \|\|
269			n > EDITOR_PASSWORDS_MAX \|\|
270	lefcha	1.9	accts[n - 1] == NULL)
271			break;
272			accts[n - 1]->password[0] = '\0';
273			printf("Enter new password: ");
274			if (fgets(accts[n - 1]->password, PASSWORD_LEN,
275			stdin) &&
276			(c = strchr(accts[n - 1]->password, '\n')))
277			*c = '\0';
278			} else if (*c == 'c') {
279			n = atoi(++c);
280	lefcha	1.11	if (n == 0 \|\| n < 1 \|\|
281			n > EDITOR_PASSWORDS_MAX \|\|
282	lefcha	1.9	accts[n - 1] == NULL)
283			break;
284			accts[n - 1]->password[0] = '\0';
285			} else if (*c == 'p') {
286			p[0] = (char *)smalloc(PASSPHRASE_LEN);
287			p[1] = (char *)smalloc(PASSPHRASE_LEN);
288			do {
289			for (i = 0; i < 2; i++) {
290			printf("Enter %snew master "
291			"password: ",
292			i ? "again " : "");
293			get_password(p[i],
294			PASSPHRASE_LEN);
295			}
296			} while (strcmp(p[0], p[1]));
297			xstrncpy(passphr, p[0], PASSPHRASE_LEN - 1);
298			sfree(p[0]);
299			sfree(p[1]);
300	lefcha	1.10	} else if (c == 's' \|\| c == 'w') {
301	lefcha	1.9	store_passwords(accts);
302			} else if (*c == 'x') {
303			store_passwords(accts);
304			q = 1;
305			} else
306			break;
307			}
308			} while (!q);
309	lefcha	1.1	}
310	lefcha	1.8
311	lefcha	1.9	#endif /* ENCRYPTED_PASSWORDS */